POLYMER PRECURSORS FOR SOLID STATE ELECTROLYTES
20210340011 · 2021-11-04
Assignee
Inventors
Cpc classification
H01M4/62
ELECTRICITY
H01M4/0471
ELECTRICITY
H01M50/451
ELECTRICITY
H01M50/414
ELECTRICITY
H01M4/131
ELECTRICITY
Y02E60/10
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
H01M4/1391
ELECTRICITY
H01M50/403
ELECTRICITY
B82Y30/00
PERFORMING OPERATIONS; TRANSPORTING
H01M10/0525
ELECTRICITY
International classification
C01B21/082
CHEMISTRY; METALLURGY
H01M10/0525
ELECTRICITY
Abstract
A method of synthesizing a precursor for making a polymer, glass, or ceramic material is provided. The method includes reacting OPCl.sub.3 with NH.sub.3 or MNH.sub.2, where M is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form O═P(NH.sub.2).sub.3. The method then includes either: (i) reacting the O═P(NH.sub.2).sub.3 with M1NH.sub.2, where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form the precursor; or (ii) heating the O═P(NH.sub.2).sub.3 to form a branched or cyclomeric compound, and reacting the branched or cyclomeric compound with M1NH.sub.2, where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form the precursor. The precursor is an oligomer or a polymer. Uses for the precursor and the polymer, glass, or ceramic material as binders, sintering aids, adhesives, and electrolytes in battery components are also provided.
Claims
1. A method of synthesizing a precursor for making a polymer, glass, or ceramic material, the method comprising: reacting OPCl.sub.3 with NH.sub.3 or MNH.sub.2, where M is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form O═P(NH.sub.2).sub.3; and either i. reacting the O═P(NH.sub.2).sub.3 with M1 NH.sub.2, where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form the precursor; or ii. heating the O═P(NH.sub.2).sub.3 to form a branched or cyclomeric compound; and reacting the branched or cyclomeric compound with M1 NH.sub.2, where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form the precursor, wherein the precursor is an oligomer or a polymer.
2. The method according to claim 1, wherein the reacting the OPCl.sub.3 with the NH.sub.3 or MNH.sub.2 is performed in a polar, aprotic solvent at a temperature of greater than or equal to about −50° C. to less than or equal to about 200° C.
3. The method according to claim 1, wherein the method comprises i. and the reacting the O═P(NH.sub.2).sub.3 with the M1 NH.sub.2 is performed at a temperature of greater than or equal to about −50° C. to less than or equal to about 200° C. to from the precursor as the oligomer.
4. The method according to claim 3, further comprising: heating the oligomer to a temperature greater than or equal to about 40° C. to less than or equal to about 300° C. to increase the molecular weight of the oligomer.
5. The method according to claim 1, wherein the method comprises i. and the reacting the O═P(NH.sub.2).sub.3 with the M1 NH.sub.2 is performed at a temperature of greater than about 20° C. to less than or equal to about 500° C. to from the precursor as the polymer.
6. The method according to claim 5, further comprising: heating the polymer to a temperature greater than or equal to about 50° C. to less than or equal to about 400° C. to increase the ceramic yield of the polymer.
7. The method according to claim 1, wherein the method comprises i. and further comprises: heating the precursor to a temperature of greater than or equal to about ambient temperature to less than or equal to about 1000° C. to form the polymer, glass, or ceramic material.
8. The method according to claim 7, further comprising, prior to the heating: applying the oligomeric or polymeric precursor to at least a portion of a surface of a battery component selected from the group consisting of a cathode, an anode, a solid electrolyte, and combinations thereof, wherein the applying is performed by a process selected from the group consisting of doctor blading, spreading, brushing, spin casting, pouring, pipetting, printing, spray coating, dip coating, and combinations thereof.
9. The method according to claim 1, wherein the method comprises ii. and the reacting is performed at a temperature of greater than or equal to about 30° C. to less than or equal to about 150° C.
10. The method according to claim 1, wherein the method comprises ii. and is performed on a surface of, and optionally in pores of, a solid-state battery component selected from the group consisting of a cathode, an anode, a solid electrode, and combinations thereof.
11. The method according to claim 1, wherein the precursor has the formula M1.sub.aM2.sub.bP.sub.mH.sub.nN.sub.xO.sub.yS.sub.z, where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof; M2 is Al, S, Se, C, Si, Ge, Sn, Zn, or combinations thereof; 1≤a≤10; 0≤b≤10; 0≤m≤50; and 0≤n≤60; 0≤x≤50; 0≤y≤20; and 0≤z≤20.
12. The method according to claim 11, wherein the precursor is PON, Li.sub.xPON, Na.sub.xPON, SiPON, Li.sub.xSiPON, Na.sub.xSiPON, LiNaSiPON, or MgSiPON, where x is 1, 1.5, 3, or 6.
13. The method according to claim 1, further comprising: combining the precursor with at least one of an electrode active material, with a separator material, or with a solid-state electrolyte material to generate at least one of a composite electrode material, a composite separator material, or a composite solid-state electrolyte material.
14. The method according to claim 1, further comprising: adding the precursor to a solution comprising an ion-conducting polymer and a solvent to form a polymer-precursor solution; casting the polymer-precursor solution on a plate; and removing the solvent from the polymer-precursor solution to form an ion-conducting polymer-precursor composite material.
15. The method according to claim 14, wherein the ion-conducting polymer is polyethylene oxide (PEO), polypropylene oxide (PPO), an ion-conducting carboxylate polymer, copolymers thereof, or mixtures thereof.
16. The method according to claim 14, wherein the solvent is acetonitrile.
17. The method according to claim 14, wherein the precursor is PON, Li.sub.xPON, Na.sub.xPON, SiPON, Li.sub.xSiPON, Na.sub.xSiPON, LiNaSiPON, or MgSiPON, where x is 1, 1.5, 3, or 6.
18. The method according to claim 14, further comprising: incorporating the ion-conducting polymer-precursor composite material into a solid-state battery as a solid composite electrolyte.
19. The oligomeric or the polymeric precursor made by the method according to claim 1.
20.-61. (canceled)
Description
DRAWINGS
[0074] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
[0075]
[0076]
[0077]
[0078]
[0079]
[0080]
[0081]
[0082]
[0083]
[0084]
[0085]
[0086]
[0087]
[0088]
[0089]
[0090]
[0091]
[0092]
[0093]
[0094]
[0095]
[0096]
[0097]
[0098]
[0099]
[0100]
[0101]
[0102]
[0103]
[0104]
[0105]
[0106]
[0107]
[0108]
[0109]
[0110]
[0111]
[0112]
[0113]
[0114]
[0115]
[0116]
[0117]
[0118]
[0119]
[0120]
[0121]
[0122]
[0123]
[0124]
[0125]
[0126]
[0127]
[0128]
[0129]
[0130]
[0131]
[0132]
[0133]
[0134]
[0135]
[0136]
[0137]
[0138]
[0139]
[0140]
[0141]
[0142]
[0143]
[0144]
[0145]
[0146]
[0147]
[0148]
[0149]
[0150]
[0151]
[0152]
[0153]
[0154]
[0155]
[0156]
[0157]
[0158]
[0159]
[0160]
[0161]
[0162]
[0163]
[0164]
[0165]
[0166]
[0167]
[0168]
[0169]
[0170]
[0171]
[0172]
[0173]
[0174]
[0175]
[0176]
[0177]
[0178]
[0179]
[0180]
[0181]
[0182]
[0183]
[0184]
[0185]
[0186] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION
[0187] Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific compositions, components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
[0188] The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, elements, compositions, steps, integers, operations, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Although the open-ended term “comprising,” is to be understood as a non-restrictive term used to describe and claim various embodiments set forth herein, in certain aspects, the term may alternatively be understood to instead be a more limiting and restrictive term, such as “consisting of” or “consisting essentially of” Thus, for any given embodiment reciting compositions, materials, components, elements, features, integers, operations, and/or process steps, the present disclosure also specifically includes embodiments consisting of, or consisting essentially of, such recited compositions, materials, components, elements, features, integers, operations, and/or process steps. In the case of “consisting of,” the alternative embodiment excludes any additional compositions, materials, components, elements, features, integers, operations, and/or process steps, while in the case of “consisting essentially of” any additional compositions, materials, components, elements, features, integers, operations, and/or process steps that materially affect the basic and novel characteristics are excluded from such an embodiment, but any compositions, materials, components, elements, features, integers, operations, and/or process steps that do not materially affect the basic and novel characteristics can be included in the embodiment.
[0189] Any method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed, unless otherwise indicated.
[0190] When a component, element, or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other component, element, or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
[0191] Spatially or temporally relative terms, such as “before,” “after,” “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially or temporally relative terms may be intended to encompass different orientations of the device or system in use or operation in addition to the orientation depicted in the figures.
[0192] Throughout this disclosure, the numerical values represent approximate measures or limits to ranges to encompass minor deviations from the given values and embodiments having about the value mentioned as well as those having exactly the value mentioned. All numerical values of parameters (e.g., of quantities or conditions) in this specification, including the appended claims, are to be understood as being modified in all instances by the term “about” whether or not “about” actually appears before the numerical value. “About” indicates that the stated numerical value allows some slight imprecision (with some approach to exactness in the value; approximately or reasonably close to the value; nearly). If the imprecision provided by “about” is not otherwise understood in the art with this ordinary meaning, then “about” as used herein indicates at least variations that may arise from ordinary methods of measuring and using such parameters.
[0193] In addition, disclosure of ranges includes disclosure of all values and further divided ranges within the entire range, including endpoints and sub-ranges given for the ranges. As referred to herein, ranges are, unless specified otherwise, inclusive of endpoints and include disclosure of all distinct values and further divided ranges within the entire range. Thus, for example, a range of “from A to B” or “from about A to about B” is inclusive of A and of B.
[0194] Example embodiments will now be described more fully with reference to the accompanying drawings.
[0195] The current technology provides polymer precursors that can be applied as overcoats to process thin film, ceramic coatings of the respective interface systems. The polymer precursors themselves, or when mixed with other ion-conducting polymers, provide ion-conducting properties that were not anticipated during their formulation as ceramic precursors.
[0196] More particularly, the current technology provides a pathway to coatings that are similar to gas phase-deposited LiPON, but that utilize solution coating of ceramic precursors. The pathway includes the synthesis of, for example, O═P(NH.sub.2).sub.3 from OPCl.sub.3 followed by lithiation by an Li source, such as LiNH.sub.2 as a non-limiting example. As an alternate method, OPCl.sub.3 is reacted with (Me.sub.3Si).sub.2NH to generate Me.sub.3SiCl and O═P(NHSiMe.sub.3).sub.3-x[NH].sub.x which can be lithiated again by LiNH.sub.2. In yet another exemplary method, the cyclomer [Cl.sub.2P═N].sub.3 reacts with (Me.sub.3Si).sub.2NH to generate Me.sub.3SiCl and [P═N](NHSiMe.sub.3).sub.33-x[NH].sub.x which can be lithiated by LiNH.sub.2 or by another source of Li.
[0197] Accordingly, the current technology provides systems that permit simple coating from solutions or from solid polymer films. These polymers have excellent Li.sup.+ conductivities alone at ambient temperature and as mixtures with other ion conducting polymers. Upon heating to various temperatures less than 1000° C., polymer precursors, which are generally oligomers, will transform to PON, LiPON, SiPON, LiSiPON, SiPHN, LiSiPHN, or other materials with various compositions. Intermediates of these materials are characterized during heating in air or nitrogen by FTIR, TGA, and XRD. Surprisingly, coatings made on a variety of substrates with or without heating show Li.sup.+ conductivities several orders of magnitude higher (10.sup.−s vs 10.sup.−6 S/cm) than those expected from gas phase deposited materials at thicknesses of greater than or equal to about 1 μm and less than or equal to about 50 μm or greater than or equal to about 1 μm and less than or equal to about 20 μm.
[0198] The current technology provides methods of synthesizing compounds, oligomers or polymers of the formula M1.sub.aM2.sub.bP.sub.mH.sub.nO.sub.xN.sub.yS.sub.z, where M.sub.1 is Li, Na, K, Mg, Ca, or Ba or combinations thereof, and M2 is S, Se, C, Si, Ge, Sn, Zn, or combinations thereof thereof. M.sub.1 is bonded to O, N, P or can bridge between two forms, such as M.sub.1O—P═N or O═P-NM.sub.1. The amount of M1 is 1≤a≤10 mol %. The amount of M2 can generally be from 0-10 times, preferably 1-5 times, with respect to the O, P, N, S or Se amounts, and is 1≤b≤10 mol %.content, n, x, y, and z are satisfy the following: 0≤m≤5a; and 0≤n≤60, 0≤x≤5a; 0≤.sub.y≤20a; 0≤z≤20a.
[0199] Oligomers or polymers having the above formula can be volatilized, dissolved and coated, melted and coated, or pressed onto or into substrates to generate polymers ceramic or glass powders, porous thin films, dense thin films, continuous interpenetrating second or third phases. Upon heating to a temperature of greater than or equal to about 100° C. to less than or equal to about 400° C. to the oligomers or polymers are formed. Upon heating to a temperature of greater than or equal to about 400° C. to less than or equal to about 1500° C. in a controlled atmosphere, the oligomers or polymers transform into, e.g., a lithium ion conducting, a sodium ion conducting, or a magnesium ion conducting, ceramic or glass coating having a thickness of greater than or equal to about 5 nm to less than or equal to about 20 μm. The coating imparts an interface to the coated substrate or powder, allowing it to be mated to another component and/or to fills pores in the substrate in order to provide semi- or continuous ion conducting sections and/or extends to the surface of a porous substrate. The coated substrate can also be used to cause one semi-flat surface to adhere strongly to another semi-flat surface, to mechanically and electrochemically bond one to the other, and to permit rapid ion diffusion across the resulting interface and/or through the substrate matrix, and/or coated particles, and/or cause particles to sinter together faster and at lower temperature to impart mechanical strength and improved electrochemical performance after heating to the temperatures of greater than or equal to about 400° C. to less than or equal to about 1500° C. in atmospheres of nitrogen, argon, hydrogen, and mixtures thereof depending on the target properties. Heating in air or oxygen is also useful for some formulations.
[0200] The current technology provides a method of synthesizing precursors to phosphorous oxynitrides, herein termed “PON”, with variable ratios of phosphorous to oxygen to nitrogen that may later be lithiated, sodiated or modified with magnesium. The PONs can be dissolved, melted or pressed to form thin films having a thickness of greater than or equal to about 5 nm to less than or equal to about 20 μm and then either the solvent is removed or the PONs are thermally converted to lithium, sodium, magnesium or mixed metal ion conductors on substrates that are powders of cathode, anode or electrolyte materials before or after processing such powders to selected forms, such as porous or dense thin films and or composites consisting of mixtures of cathode and electrically conducting materials such as carbon in any form, and/or forming thin films on preformed porous or dense films and also used to promote sintering at lower temperatures than without coatings and that coincidentally provide improved mechanical and electrochemical properties.
[0201] The current technology also provides a method of synthesizing precursors to silicon modified phosphorous oxynitrides, herein termed “SiPON”, with variable ratios of silicon to phosphorous to oxygen to nitrogen that may be later lithiated, sodiated or modified with magnesium and that can be dissolved, melted or pressed to form thin films having a thickness of greater than or equal to about 5 nm to less than or equal to about 20 μm and then thermally converted to lithium, sodium, magnesium or mixed metal ion conductors on substrates that are powders of cathode, anode or electrolyte materials before or after processing such powders to selected forms such as porous or dense thin films and or composites consisting of mixtures of cathode and electrically conducting materials such as carbon in any form and or forming thin films on preformed porous or dense films and also used to promote sintering at lower temperatures than without coatings and that coincidentally provide improved mechanical and electrochemical properties.
[0202] The current technology also provides a method of synthesizing precursors to sodium and silicon modified phosphorous oxynitrides, herein termed “NaSiPON”, with variable ratios of sodium and silicon to phosphorous to oxygen to nitrogen that may be later lithiated or modified with magnesium and that can be dissolved, melted or pressed to form thin films having a thickness of greater than or equal to about 5 nm to less than or equal to about 20 μm and then thermally converted to lithium, sodium, magnesium or mixed metal ion conductors on substrates that are powders of cathode, anode or electrolyte materials before or after processing such powders to selected forms such as porous or dense thin films and or composites consisting of mixtures of cathode and electrically conducting materials such as carbon in any form and or forming thin films on preformed porous or dense films and also used to promote sintering at lower temperatures than without coatings and that coincidentally provide improved mechanical and electrochemical properties.
[0203] The current technology also provides a method of synthesizing precursors to magnesium and silicon modified phosphorous oxynitrides, herein termed “MgSiPON”, with variable ratios of magnesium and silicon to phosphorous to oxygen to nitrogen that may be later lithiated or sodiated and that can be dissolved, melted or pressed to form thin films having a thickness of greater than or equal to about 5 nm to less than or equal to about 20 μm and then thermally converted to lithium, sodium, magnesium or mixed metal ion conductors on substrates that are powders of cathode, anode or electrolyte materials before or after processing such powders to selected forms such as porous or dense thin films and or composites consisting of mixtures of cathode and electrically conducting materials such as carbon in any form and or forming thin films on preformed porous or dense films and also used to promote sintering at lower temperatures than without coatings and that coincidentally provide improved mechanical and electrochemical properties.
[0204] In various embodiments, the methods include the following steps.
##STR00001##
[0205] In various embodiments, the oligomers or polymers have the exemplary structures shown in
[0206] In various embodiments, the oligomeric or polymeric precursor infiltrates a porous substrate, provides reinforcement, i.e., increased strength, and provides an ion-conducting pathway by forming electrolyte pathways within a substrate as well as coating the surface, as shown in
[0207] Accordingly, the current technology provides a method of synthesizing a polymer or ceramic material precursor. The method includes reacting a compound according to one of the following pathways. The compound satisfies the formula P.sub.xO.sub.yN.sub.zX.sub.mH.sub.nC.sub.o, where 1≤x≤20, 1≤x≤10, 1≤x≤5; 0≤y≤20, 0≤y≤10, 0≤y≤5; 1≤z≤20, 1≤z≤10, 1≤z≤5; X is Cl, Br, I, CN or mixtures thereof; 1≤m≤20, 1≤m≤15, 1≤m≤10; 0≤n≤20, 0≤n≤10, 0≤n≤5; and 0≤o≤20, 0≤o≤10, 0≤o≤5. The compound is soluble in aprotic solvents.
[0208] In a first pathway, X is a halogen. The compound is reacted with NH.sub.3 to form NH.sub.4X (a byproduct removed by filtration) and the intermediate P.sub.xO.sub.yN.sub.z+mH.sub.n+(m−1 or m−2)C.sub.o. The intermediate is warmed at a temperature of greater than or equal to about 10° C. to less than or equal to about 150° C. in solution or in a solid phase to eliminate NH.sub.3 and form an oligomeric, or polymeric precursor, which remains soluble in aprotic solvents and meltable.
[0209] In another pathway, the compound is reacted with MNH.sub.2 or M(NH.sub.2).sub.2 or mixtures thereof, where M=Li, Na, K, Ca, Mg, or Ba to form the intermediate P.sub.xO.sub.yN.sub.z+mH.sub.n+(m−1 or m−2)C.sub.o coincident with MX.sub.1(2). The intermediate is warmed at a temperature of greater than or equal to about 10° C. to less than or equal to about 150° C. in solution or in a solid phase to eliminate NH.sub.3 to an oligomeric, or polymeric precursor, which remains soluble in aprotic solvents and meltable.
[0210] In some variations, excess MNH.sub.2 or M(NH.sub.2).sub.2 or mixtures thereof are used to form the second intermediate M.sub.1M.sub.2P.sub.xO.sub.yN.sub.zX.sub.mH.sub.nC.sub.o. The second intermediate is warmed at a temperature of greater than or equal to about 10° C. to less than or equal to about 150° C. in solution or in a solid phase to eliminate NH.sub.3 to an oligomeric, or polymeric precursor, which remains soluble in aprotic solvents and meltable.
[0211] In another pathway, the compound is reacted with silyl compounds as exemplified by (R.sub.3Si).sub.2NH (where R is C.sub.1-C.sub.8 alkyl or H) to generate volatile R.sub.3SiX, which can be evaporated from solution before or after recovery of the intermediate (R.sub.3Si).sub.mP.sub.xO.sub.yN.sub.z+mH.sub.n+(m−1 or m−2)C.sub.o. The intermediate is warmed at a temperature of greater than or equal to about 10° C. to less than or equal to about 150° C. in solution or in a solid phase to eliminate NH.sub.3 (or R.sub.3SiNH.sub.2) to an oligomeric, or polymeric precursor, which remains soluble in aprotic solvents and meltable.
[0212] Alternately, the intermediate is treated with MNH.sub.2 or M(NH.sub.2).sub.2 or mixtures thereof to produce the intermediate M.sub.1M.sub.2(R.sub.3Si).sub.mP.sub.xO.sub.yN.sub.z+mH.sub.n+(m−2,3,−6)C.sub.o (where R is C.sub.1-C.sub.8 alkyl or H). This intermediate is heated gently at a temperature of greater than or equal to about 10° C. to less than or equal to about 150° C. to produce a higher molecular weight aprotic-solvent soluble and meltable precursor.
[0213] The current technology provides another method of synthesizing a precursor for making a polymeric, glass, or ceramic material. The method comprises reacting OPCl.sub.3 with NH.sub.3 or MNH.sub.2, where M is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form O═P(NH.sub.2).sub.3. The reacting the OPCl.sub.3 with MNH.sub.2 is performed in a polar, aprotic solvent at a temperature of greater than or equal to about −50° C. to less than or equal to about 200° C., greater than or equal to about 0° C. to less than or equal to about 150° C., or greater than or equal to about 20° C. to less than or equal to about 70° C., thus forming a reaction mixture. Non-limiting examples of polar, aprotic solvents include tetrahydrofuran (THF), dimethoxyethane (glyme), bis(2-methoxyethyl) ether (diglyme), acetone, N—N-dimethylformamide (DMF), acetonitrile (MeCN), dimethyl sulfoxide (DMSO), and combinations thereof.
[0214] The method then comprises reacting the O═P(NH.sub.2).sub.3 with M1NH.sub.2, where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form the precursor as an oligomer or a polymer. The reacting comprises adding the M1NH.sub.2 to the reaction mixture. To form the oligomer, the reacting the O═P(NH.sub.2).sub.3 with the M1NH.sub.2, is performed at a temperature of greater than or equal to about −50° C. to less than or equal to about 200° C., greater than or equal to about 0° C. to less than or equal to about 150° C., or greater than or equal to about 25° C. to less than or equal to about 100° C. To form the polymer, the reacting the O═P(NH.sub.2).sub.3 with the M1NH.sub.2 is performed at a temperature of greater than or equal to about 20° C. to less than or equal to about 500° C., greater than or equal to about 50° C. to less than or equal to about 450° C., or greater than or equal to about 75° C. to less than or equal to about 400° C. In some embodiments, the O═P(NH.sub.2).sub.3 is heated to form a branched or cyclomeric compound and then reacted with the M1NH.sub.2 as discussed above.
[0215] In some embodiments the method further comprises increasing the molecular weight of the oligomeric precursor by heating the oligomeric precursor to a temperature of greater than or equal to about 40° C. to less than or equal to about 300° C., greater than or equal to about 50° C. to less than or equal to about 250° C., or greater than or equal to about 75° C. to less than or equal to about 200° C. In other embodiments, the method further comprises increasing a ceramic yield of the polymeric precursor by heating the polymeric precursor to a temperature of greater than or equal to about 50° C. to less than or equal to about 400° C., greater than or equal to about 75° C. to less than or equal to about 350° C., or greater than or equal to about 100° C. to less than or equal to about 300° C.
[0216] The precursor itself can be used in a variety of embodiments. As non-limiting examples, the precursor can be used: (1) as a solid-state electrolyte for a solid-state battery that cycles lithium or sodium ions; (2) to generate composite electrolyte films, e.g., ion-conducting polymer-precursor composite material, wherein the ion-conducting polymer is polyethylene oxide (PEO), polypropylene oxide (PPO), an ion-conducting carboxylate polymer, copolymers thereof, or mixtures thereof; (3) as a film coating on a polymer separator, including for use in a symmetric cell; (4) to generate composite films on a substrate that is not a separator, including for use in a symmetric cell, e.g., PEO/precursor composite films substrates; (5) as a binder in an anode active material and/or in a cathode active material; and (6) as a ceramic-forming adhesive.
[0217] The oligomeric or polymeric precursor can optionally be transformed into the polymer, glass or ceramic material by heating the oligomeric or polymeric precursor to a temperature of greater than or equal to about ambient temperature to less than or equal to about 1500° C., greater than or equal to about ambient temperature to less than or equal to about 1000° C., or greater than or equal to about 100° C. to less than or equal to about 1000° C. to form the polymer, glass, or ceramic material. As used herein, a “glass” is a non-crystalline (amorphous)inorganic material that has glass transition and a “ceramic” is a crystalline, semi-crystalline, or non-crystalline inorganic material that does not have a glass transition.
[0218] The polymer, glass, or ceramic precursor material can be used, as non-limiting examples, as a bonding agent between components of a solid-state electrode, to fill pores in a solid-state battery component, as a polymer applied to a ceramic substrate, or as a sintering aid. In various embodiments, the method further comprises applying the oligomeric or polymeric precursor to at least a portion of a surface, and optionally within pores, of a battery component selected from the group consisting of a cathode, an anode, a solid electrolyte, and combinations thereof, and then heating to form the ceramic material as described above. A second solid-state battery component can be disposed on top of the oligomeric or polymeric precursor before the heating in order to generate a ceramic bond or interface between the components after the heating. The applying can be performed by any method known in the art, such as by a process selected from the group consisting of doctor blading, spreading, brushing, spin casting, pouring, pipetting, printing, spray coating, dip coating, and combinations thereof as non-limiting examples. In some embodiments, the solid-state battery component is dip-coated into the oligomeric or polymeric precursor, and then the heating is performed to generate a solid coating that surrounds the solid-state battery component and fills pores within the component when present. The ceramic material can be substantially free of pinholes, i.e., holes having a diameter of greater than or equal to about 5 nm to less than or equal to about 20 nm. By “substantially free” it is meant that less than about 5%, less than about 2.5%, less than 1%, or less than 0.5% of the ceramic material comprises pinholes. The glass or ceramic material is conductive to ions, such as Li, Na, Mg, or Si ions. In some embodiments, the glass or ceramic material includes pinholes, which can be filled with the same or different glass or ceramic material.
[0219] The current technology provides another method of synthesizing a precursor for making a polymer, glass, or ceramic material. The method comprises reacting OPCl.sub.3 with NH.sub.3 or MNH.sub.2, where M is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form O═P(NH.sub.2).sub.3. The reacting the OPCl.sub.3 with MNH.sub.2 is performed in a polar, aprotic solvent at a temperature of greater than or equal to about −50° C. to less than or equal to about 200° C., greater than or equal to about 0° C. to less than or equal to about 150° C., or greater than or equal to about 20° C. to less than or equal to about 70° C.; thus forming a reaction mixture. Non-limiting examples of polar, aprotic solvents include tetrahydrofuran (THF), dimethoxyethane (glyme), bis(2-methoxyethyl) ether (diglyme), acetone, N—N-dimethylformamide (DMF), acetonitrile (MeCN), dimethyl sulfoxide (DMSO), and combinations thereof.
[0220] The method then comprises heating the O═P(NH.sub.2).sub.3 to form a branched or cyclomeric compound and reacting the branched or cyclomeric compound with M1NH.sub.2, where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof, to form the precursor. as an oligomer or a polymer. To form the oligomer, the reacting the O═P(NH.sub.2).sub.3 with the M1NH.sub.2, is performed at a temperature of greater than or equal to about −50° C. to less than or equal to about 200° C., greater than or equal to about 0° C. to less than or equal to about 150° C., or greater than or equal to about 25° C. to less than or equal to about 100° C. To form the polymer, the reacting the O═P(NH.sub.2).sub.3 with the M1NH.sub.2 is performed at a temperature of greater than or equal to about 20° C. to less than or equal to about 500° C., greater than or equal to about 50° C. to less than or equal to about 450° C., or greater than or equal to about 75° C. to less than or equal to about 400° C.
[0221] In some embodiments the method further comprises increasing the molecular weight of the oligomeric precursor by heating the oligomeric precursor to a temperature of greater than or equal to about 40° C. to less than or equal to about 300° C., greater than or equal to about 50° C. to less than or equal to about 250° C., or greater than or equal to about 75° C. to less than or equal to about 200° C. In other embodiments, the method further comprises increasing a ceramic yield of the polymeric precursor by heating the polymeric precursor to a temperature of greater than or equal to about 50° C. to less than or equal to about 400° C., greater than or equal to about 75° C. to less than or equal to about 350° C., or greater than or equal to about 100° C. to less than or equal to about 300° C.
[0222] The precursor itself can be used in a variety of embodiments. As non-limiting examples, the precursor can be used: (1) as a solid-state electrolyte for a solid-state battery that cycles lithium or sodium ions; (2) to generate composite electrolyte films, e.g., ion-conducting polymer-precursor composite material, wherein the ion-conducting polymer is polyethylene oxide (PEO), polypropylene oxide (PPO), an ion-conducting carboxylate polymer, copolymers thereof, or mixtures thereof; (3) as a film coating on a polymer separator, including for use in a symmetric cell; (4) to generate composite films on a substrate that is not a separator, including for use in a symmetric cell, e.g., PEO/precursor composite films substrates; (5) as a binder in an anode active material and/or in a cathode active material; and (6) as a ceramic-forming adhesive.
[0223] The oligomeric or polymeric precursor can optionally be transformed into the polymer glass or ceramic material by heating the oligomeric or polymeric precursor to a temperature of greater than or equal to about ambient temperature to less than or equal to about 1500° C., greater than or equal to about ambient temperature to less than or equal to about 1000° C., or greater than or equal to about 100° C. to less than or equal to about 1000° C. to form the polymer, glass, or ceramic material.
[0224] The glass or ceramic material can be used, as non-limiting examples, as a bonding agent between components of a solid-state electrode, to fill pores in a solid-state battery component, as a ceramic disposed on a ceramic substrate, or as a sintering aid. In various embodiments, the method further comprises applying the oligomeric or polymeric precursor to at least a portion of a surface, and optionally within pores, of a battery component selected from the group consisting of a cathode, an anode, a solid electrolyte, and combinations thereof, and then heating to form the ceramic material as described above. A second solid-state battery component can be disposed on top of the oligomeric or polymeric precursor before the heating in order to generate a ceramic bond or interface between the components after the heating. The applying can be performed by any method known in the art, such as by a process selected from the group consisting of doctor blading, spreading, brushing, spin casting, pouring, pipetting, printing, spray coating, dip coating, and combinations thereof as non-limiting examples. In some embodiments, the solid-state battery component is dip-coated into the oligomeric or polymeric precursor, and then the heating is performed to generate a solid coating that surrounds the solid-state battery component and fills pores within the component when present. The ceramic material can be substantially free of pinholes, i.e., holes having a diameter of greater than or equal to about 5 nm to less than or equal to about 20 nm. By “substantially free” it is meant that less than about 5%, less than about 2.5%, less than 1%, or less than 0.5% of the ceramic material comprises pinholes. The some embodiments, the glass or ceramic material includes pinholes, which can be filled with the same or different glass or ceramic material.
[0225] The current technology further provides another method of synthesizing a precursor for making a polymer, glass, or ceramic material. The method comprises reacting OPCl.sub.3 with (Me.sub.3X).sub.2NH, where Me is methyl and X is Si, Ge, Sn, or combinations thereof, to form O═P(NHSiMe.sub.3).sub.3. Although it is understood that other alkyl groups other than methyl can be used, the use of methyl is described herein. The reacting OPCl.sub.3 with (Me.sub.3X).sub.2NH, is performed in a polar, aprotic solvent as described above; thus forming a reaction mixture, and at a temperature of greater than or equal to about −50° C. to less than or equal to about 200° C., greater than or equal to about −10° C. to less than or equal to about 150° C., greater than or equal to about 20° C. to less than or equal to about 120° C., or greater than or equal to about 40° C. to less than or equal to about 100° C. for a time of greater than or equal to about 2 minutes to less than or equal to about 10 hours, greater than or equal to about 30 minutes to less than or equal to about 8 hours, or greater than or equal to about 1 hour to less than or equal to about 6 hours.
[0226] The method then comprises adding M1NH.sub.2 to the reaction mixture and reacting the O═P(NHSiMe.sub.3).sub.3 with the M1NH.sub.2, where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof to form the precursor as an oligomer or a polymer. To form the oligomer, the reacting the O═P(NHSiMe.sub.3).sub.3 with the M1NH.sub.2 is performed at a temperature of greater than or equal to about −50° C. to less than or equal to about 200° C., greater than or equal to about 0° C. to less than or equal to about 150° C., or greater than or equal to about 25° C. to less than or equal to about 100° C. To form the polymer, the reacting the O═P(NHSiMe.sub.3).sub.3 with the M1NH.sub.2 is performed at a temperature of greater than or equal to about 20° C. to less than or equal to about 500° C., greater than or equal to about 50° C. to less than or equal to about 450° C., or greater than or equal to about 75° C. to less than or equal to about 400° C.
[0227] In some embodiments the method further comprises increasing the molecular weight of the oligomeric precursor by heating the oligomeric precursor to a temperature of greater than or equal to about 40° C. to less than or equal to about 300° C., greater than or equal to about 50° C. to less than or equal to about 250° C., or greater than or equal to about 75° C. to less than or equal to about 200° C. In other embodiments, the method further comprises increasing a ceramic yield of the polymeric precursor by heating the polymeric precursor to a temperature of greater than or equal to about 50° C. to less than or equal to about 400° C., greater than or equal to about 75° C. to less than or equal to about 350° C., or greater than or equal to about 100° C. to less than or equal to about 300° C.
[0228] In some embodiments, at least one of Al, Zn, S, or Se is introduced into the oligomeric or polymeric precursor. In order to introduce Al and/or Zn, the method comprises reacting the oligomeric or polymeric precursor with at least one of Y(OR).sub.n, Y(O.sub.2CR′).sub.n, Y(NO.sub.3).sub.n, and YCl.sub.n, wherein Y is Al or Zn, n is 3 when Y is Al, n is 2 when Y is Zn, and R and R′ are independently a saturated C1-C5 alkyl that is branched or unbranched, and substituted or unsubstituted, such as methyl or propyl as non-limiting examples. In order to introduce S and/or Se, the method comprises reacting the oligomeric or polymeric precursor with at least one of Li.sub.2S or Li.sub.2Se at a temperature of greater than or equal to about room temperature to less than or equal to about 80° C.
[0229] The precursor itself can be used in a variety of embodiments. As non-limiting examples, the precursor can be used: (1) as a solid-state electrolyte for a solid-state battery that cycles lithium or sodium ions; (2) to generate composite electrolyte films, e.g., ion-conducting polymer-precursor composite material, wherein the ion-conducting polymer is polyethylene oxide (PEO), polypropylene oxide (PPO), an ion-conducting carboxylate polymer, copolymers thereof, or mixtures thereof; (3) as a film coating on a polymer separator, including for use in a symmetric cell; (4) to generate composite films on a substrate that is not a separator, including for use in a symmetric cell, e.g., PEO/precursor composite films substrates; (5) as a binder in an anode active material and/or in a cathode active material; and (6) as a ceramic-forming adhesive.
[0230] The oligomeric or polymeric precursor can optionally be transformed into the polymer, glass, or ceramic material by heating the oligomeric or polymeric precursor to a temperature of greater than or equal to about ambient temperature to less than or equal to about 1500° C., greater than or equal to about ambient temperature to less than or equal to about 1000° C., or greater than or equal to about 100° C. to less than or equal to about 1000° C. to form the polymer, glass or ceramic material.
[0231] The ceramic material can be used, as non-limiting examples, as a bonding agent between components of a solid-state electrode, to fill pores in a solid-state battery component, as a ceramic disposed on a ceramic substrate, or as a sintering aid. In various embodiments, the method further comprises applying the oligomeric or polymeric precursor to at least a portion of a surface, and optionally within pores, of a battery component selected from the group consisting of a cathode, an anode, a solid electrolyte, and combinations thereof, and then heating to form the ceramic material as described above. A second solid-state battery component can be disposed on top of the oligomeric or polymeric precursor before the heating in order to generate a ceramic bond or interface between the components after the heating. The applying can be performed by any method known in the art, such as by a process selected from the group consisting of doctor blading, spreading, brushing, spin casting, pouring, pipetting, printing, spray coating, dip coating, and combinations thereof as non-limiting examples. In some embodiments, the solid-state battery component is dip-coated into the oligomeric or polymeric precursor, and then the heating is performed to generate a solid coating that surrounds the solid-state battery component and fills pores within the component when present. The ceramic material can be substantially free of pinholes, i.e., holes having a diameter of greater than or equal to about 5 nm to less than or equal to about 20 nm. By “substantially free” it is meant that less than about 5%, less than about 2.5%, less than 1%, or less than 0.5% of the ceramic material comprises pinholes. The ceramic material is conductive to ions, such as Li, Na, Mg, or Si ions. In some embodiments, the glass or ceramic material includes pinholes, which can be filled with the same or different glass or ceramic material.
[0232] The current technology yet further provides another method of synthesizing a precursor for making a polymer, glass, or ceramic material. The method comprises reacting Cl.sub.6N.sub.3P.sub.3 with NH(SiMe.sub.3).sub.2 to form the precursor as either a SiPHN oligomer precursor or a SiPHN polymer precursor. To form the SiPHN oligomer precursor, the reacting the Cl.sub.6N.sub.3P.sub.3 with the NH(SiMe.sub.3).sub.2 is performed at a temperature of greater than or equal to about −50° C. to less than or equal to about 200° C., greater than or equal to about 0° C. to less than or equal to about 150° C., or greater than or equal to about 25° C. to less than or equal to about 100° C. To form the SiPHN polymer precursor, the reacting the Cl.sub.6N.sub.3P.sub.3 with the NH(SiMe.sub.3).sub.2 is performed at a temperature of greater than or equal to about 20° C. to less than or equal to about 500° C., greater than or equal to about 50° C. to less than or equal to about 450° C., or greater than or equal to about 75° C. to less than or equal to about 400° C.
[0233] In various embodiments, the method further includes reacting the SiPHN precursor with MNH.sub.2, where M is Li, Na, K, Mg, Ca, Ba, or combinations thereof to form a MSiPHN precursor as either a MSiPHN oligomer precursor or a MSiPHN polymer precursor. To form the MSiPHN oligomer precursor, the reacting the Cl.sub.6N.sub.3P.sub.3 with the NH(SiMe.sub.3).sub.2 is performed at a temperature of greater than or equal to about −50° C. to less than or equal to about 200° C., greater than or equal to about 0° C. to less than or equal to about 150° C., or greater than or equal to about 25° C. to less than or equal to about 100° C. To form the MSiPHN polymer precursor, the reacting the Cl.sub.6N.sub.3P.sub.3 with the NH(SiMe.sub.3).sub.2 is performed at a temperature of greater than or equal to about 20° C. to less than or equal to about 500° C., greater than or equal to about 50° C. to less than or equal to about 450° C., or greater than or equal to about 75° C. to less than or equal to about 400° C.
[0234] In some embodiments the method further comprises increasing the molecular weight of the SiPHN or MSiPHN oligomer precursor by heating the SiPHN or MSiPHN oligomer precursor to a temperature of greater than or equal to about 40° C. to less than or equal to about 300° C., greater than or equal to about 50° C. to less than or equal to about 250° C., or greater than or equal to about 75° C. to less than or equal to about 200° C. In other embodiments, the method further comprises increasing a ceramic yield of the SiPHN or MSiPHN polymer precursor by heating the SiPHN or MSiPHN polymeric precursor to a temperature of greater than or equal to about 50° C. to less than or equal to about 400° C., greater than or equal to about 75° C. to less than or equal to about 350° C., or greater than or equal to about 100° C. to less than or equal to about 300° C.
[0235] The SiPHN precursor or the MSiPHN precursor themselves can be used in a variety of embodiments. As non-limiting examples, the precursors can be used: (1) as a solid-state electrolyte for a solid-state battery that cycles lithium or sodium ions; (2) to generate composite electrolyte films, e.g., ion-conducting polymer-precursor composite material, wherein the ion-conducting polymer is polyethylene oxide (PEO), polypropylene oxide (PPO), an ion-conducting carboxylate polymer, copolymers thereof, or mixtures thereof; (3) as a film coating on a polymer separator, including for use in a symmetric cell; (4) to generate composite films on a substrate that is not a separator, including for use in a symmetric cell, e.g., PEO/precursor composite films substrates; (5) as a binder in an anode active material and/or in a cathode active material; and (6) as a ceramic-forming adhesive.
[0236] The SiPHN precursor or the MSiPHN precursor can optionally be transformed into the corresponding polymer glass or ceramic material by heating the SiPHN precursor or the MSiPHN precursor to a temperature of greater than or equal to about ambient temperature to less than or equal to about 1500° C., greater than or equal to about ambient temperature to less than or equal to about 1000° C., or greater than or equal to about 100° C. to less than or equal to about 1000° C. to form the polymer, glass, or ceramic material.
[0237] The glass or ceramic material can be used, as non-limiting examples, as a bonding agent between components of a solid-state electrode, to fill pores in a solid-state battery component, as a ceramic disposed on a ceramic substrate, or as a sintering aid. In various embodiments, the method further comprises applying the oligomeric or polymeric precursor to at least a portion of a surface, and optionally within pores, of a battery component selected from the group consisting of a cathode, an anode, a solid electrolyte, and combinations thereof, and then heating to form the ceramic material as described above. A second solid-state battery component can be disposed on top of the oligomeric or polymeric precursor before the heating in order to generate a ceramic bond or interface between the components after the heating. The applying can be performed by any method known in the art, such as by a process selected from the group consisting of doctor blading, spreading, brushing, spin casting, pouring, pipetting, printing, spray coating, dip coating, and combinations thereof as non-limiting examples. In some embodiments, the solid-state battery component is dip-coated into the oligomeric or polymeric precursor, and then the heating is performed to generate a solid coating that surrounds the solid-state battery component and fills pores within the component when present. The ceramic material can be substantially free of pinholes, i.e., holes having a diameter of greater than or equal to about 5 nm to less than or equal to about 20 nm. By “substantially free” it is meant that less than about 5%, less than about 2.5%, less than 1%, or less than 0.5% of the ceramic material comprises pinholes. The some embodiments, the glass or ceramic material includes pinholes, which can be filled with the same or different glass or ceramic material.
[0238] The current technology also provides a method of fabricating a solid-state battery that comprises applying any of the oligomeric or polymeric precursors described herein to a battery component, and heating the oligomeric or polymeric precursor to form a ceramic material. The battery component can be, for example, an anode, a cathode, a solid-state electrolyte, a separator, or a combination thereof. The polymeric precursors can be added to a battery component material prior to the heating in order to generate a composite battery component material or the polymeric precursors can be applied over the battery component in order to generate a coated battery component. Alternatively, as discussed above, in some embodiments the precursor is included in the battery component without heating and conversion into a ceramic material.
[0239] The current technology also provides an oligomeric or polymeric precursor made by any of the above methods.
[0240] The current technology also provides a ceramic material made from an oligomeric or polymeric precursor by any of the above methods
[0241] The current technology also provides a solid state battery comprising a ceramic material made by any of the above methods. The ceramic material is disposed on at least one of an anode, a cathode, a separator, or a solid-state electrolyte.
[0242] The current technology yet further provides a compound having the formula M1.sub.aM2.sub.bP.sub.mH.sub.nO.sub.xN.sub.yS.sub.z where M1 is Li, Na, K, Mg, Ca, Ba, or combinations thereof; M2 is Al, S, Se, C, Si, Ge, Sn, Zn, or combinations thereof; 1≤a≤10; 0≤b≤10; 0≤m≤5a; and 0≤n≤60, 0≤x≤5a; 0≤y≤20a; 0≤z≤20a, wherein the compound is an oligomer, or polymer that is configured to form a coating, a bonding material, or an ion conducting pathway through a porous material. The compound is made according to any of the methods provided herein. The compound can optionally be heated as described above in order to be transformed into a ceramic material.
[0243] The current technology also provides a solid-state battery comprising a ceramic material formed from the compound having the formula M1.sub.aM2.sub.bN.sub.xO.sub.yP.sub.zH.sub.c.
[0244] Embodiments of the present technology are further illustrated through the following non-limiting examples.
EXAMPLES
[0245] In order to demonstrate the utility of making precursors according to the current technology, it is also important to have a set of substrates qualified to be used to test the efficacy of the coatings and processing conditions explored. To optimize ion conductivity in the resulting ceramized precursors, well-defined substrates are needed that offer: (1) no lithium or sodium ion conductivity; (2) minimal lithium or sodium ion conductivity; or (3) good lithium or sodium ion conductivity. The below approaches either use a polymer separator as a substrate or eliminate the need for a ceramic substrate.
[0246] To this end, a series of produced substrates are chosen that are typically 10-50 μm thick and fully or partially dense and meet the criteria just above. Thus, thin films of α-Al.sub.2O.sub.3, LiAlO.sub.2 of various densities, and LATSP (Li.sub.1.7Al.sub.0.3Ti.sub.1.7Si.sub.0.4P.sub.2.6O.sub.12) are coated. Substrates of these materials exhibit Li.sup.+ conductivities as shown in Table 1.
TABLE-US-00001 TABLE 1 Substrates used in coating studies Substrate Thickness σ.sub.t(S cm.sup.−1) α-Al.sub.2O.sub.3 ≥25 μm N/A LiAlO.sub.2 20-60 μm 1.6 × 10.sup.−8 LATSP.sup.17 20-60 μm 4.3 × 10.sup.−4 ± 1.4 × 10.sup.−4
[0247] The first step in developing precursors is to realize, simple low cost, minimal step syntheses of precursor systems that are easily modified to allow exploration, and thereafter, control of both precursor properties and processing conditions necessary to generate optimal coating, binder and bonding systems. Thus, work to explore synthetic approaches to various precursors is described.
[0248] Precursor Syntheses.
[0249] Polymer Precursor Reactions for PON and Li.sub.xPON.
[0250] Several approaches can be used for these precursors. Perhaps the simplest is ammonolysis of OPCl.sub.3 to produce the phosphoramide OP(NH.sub.2).sub.3:
##STR00002##
[0251] However, depending on the solvent used, byproduct NH.sub.4Cl is difficult to remove or interfere with purification. An alternative uses NaNH.sub.2 as follows:
##STR00003##
[0252] The reason for using NaNH.sub.2 rather than LiNH.sub.2 is that LiCl is more soluble in polar solvents than NaCl and may not precipitate as easily, and thus, NaNH.sub.2 is preferable in some embodiments.
[0253] Thereafter, there are two options for producing LiPON precursors. The first is to promote oligomerization/polymerization following reactions shown as stepwise condensation reactions (in which “slight heat” refers to heating from greater than or equal to about −10° C. to less than or equal to about 100° C.):
##STR00004##
[0254] As shown, only linear oligomers are formed. However, it is highly likely that both branched and cyclomeric products are produced coincidentally:
##STR00005##
[0255] The volatile system offers a novel method for chemical vapor deposition. At this juncture, it is possible to now add Li as shown below:
##STR00006##
[0256] As an alternative, it is preferred that this be done right after the first step. This may not be optimal, but it appears to be the easiest approach:
##STR00007##
[0257] The Li content can be controlled by the degree of initial lithiation. Promoting a condensation reaction can also take place as described above. The condensation process is very likely to be much more complex than shown. However, one can use these intermediates as precursors to make LiPON thin films, binders or bonding agents by using traditional precursor processing techniques. In some instances, the intermediates will be liquids and in others, they will be meltable or soluble solids.
[0258] As demonstrated in the examples described below, it is possible to make Li.sub.1.5PON, Li.sub.3PON and Li.sub.6PON precursors simply by choosing the amount of LiNH.sub.2 to add. It is also possible to make a sodium equivalent by adding more NaNH.sub.2 to make a NaPON precursor, for example Na.sub.3PON. It is also possible to make a mixed ion precursor by adding both NaNH.sub.2 and LiNH.sub.2 in any possible ratio desired as demonstrated in the examples below.
[0259] Finally, a magnesium counterpart can be made by adding a magnesium amide such as Mg(NiPr.sub.2).sub.2, which is used as an example and not meant to be limiting. Again, a mixed ion precursor can also be made by using any type of Na, Li or Mg compound that has the potential to either abstract a hydrogen from O═P(NH.sub.2).sub.3 or oligomeric analogs replacing said hydrogen with that metal and any ratio of metals can be chosen to optimize ionic conductivity and other processing properties.
[0260] Polymer Precursors to LiSiPON.
[0261] The synthesis of silicon containing LiPON or LiSiPON has been previously reported. The following approach to precursors has not been used. In its simplest form, it takes advantage of the affinity of Si for Cl:
##STR00008##
[0262] Another embodiment uses less than 2.5 (Me.sub.3Si).sub.2NH:
##STR00009##
[0263] At this stage, the above compound can be lithiated (or use sodium or magnesium):
##STR00010##
and then heated, as suggested by the following which is not meant to be the only reaction pathway:
##STR00011##
[0264] The resulting material's composition will depend on the original amount of LiNH.sub.2 [NaNH.sub.2 or Mg(NiPr).sub.2] or other deprotonating metallating compound introduced, and the conductivity will be determined by this as well as processing conditions. Thus, Li.sub.1.5SiPON, Li.sub.3SiPON, Li.sub.6SiPON, Na.sub.3SiPON, and Mg.sub.1.5SiPON can be made as non-limiting exemplary M.sub.1M.sub.2P.sub.mH.sub.nO.sub.xN.sub.yS.sub.z compounds.
[0265] SiPHN and Li.sub.xSPHN systems
[0266] The use of a polymer that is solely based on phosphorus and nitrogen is explored. The scheme starts form the cyclomer [Cl.sub.2P═N].sub.3 and replaces Cl with NH via a Si—Cl exchange process.
##STR00012##
[0267] These examples demonstrate an approach for formulating systems for making processable polymers by using non-stoichiometric amounts of (Me.sub.3Si).sub.2NH.
[0268] Experimental Methods.
[0269] Materials. Aluminum tri-sec-butoxide {Al[OCH(CH.sub.3)CH.sub.2CH.sub.3].sub.3} is purchased from Chattem Chemicals (Chattanooga, Tenn.), and absolute ethanol from Decon Labs (King of Prussia, Pa.). Triethanolamine [N(CH.sub.2CH.sub.2OH).sub.3], Polyacrylic acid [(C.sub.3H.sub.4O.sub.2).sub.n, M.sub.n 2000], Polyethylene glycol [H(OCH.sub.2CH.sub.2).sub.nOH, M.sub.n 3400], Methyl ethyl ketone [C.sub.2H.sub.5COCH.sub.3], Benzyl butyl phthalate {2-[CH.sub.3(CH.sub.2).sub.3O.sub.2C] C.sub.6H.sub.4CO.sub.2CH.sub.2C.sub.6H.sub.5, 98%}, Lithium hydroxide monohydrate [LiOH.Math.H.sub.2O] and Propionic acid [CH.sub.3CH.sub.2COOH] are purchased from Sigma-Aldrich (Milwaukee, Wis.). Polyvinyl butyral [(C.sub.8H.sub.14O.sub.2).sub.n, B-98, M.sub.n 40,000-70,000] is purchased from Butvar (Avon, Ohio). Tetraethoxysilane [Si(OC.sub.2H.sub.5).sub.4], Triethyl phosphate [(C.sub.2H.sub.5O).sub.3PO], Titanium isopropoxide [Ti(OiPr).sub.4] is purchased from Fischer Scientific (Pittsburgh, Pa.).
[0270] Analytical Methods.
[0271] Thermal gravimetric analysis (TGA) and differential thermal analysis (DTA) are performed on a SDT Q600 simultaneous TGA/DSC (TA instrument, Inc.). Samples (15-25 mg), hand pressed in a 3-mm dual action die, are placed in alumina pans and heated to 1000° C. at 10° C. min.sup.−1 under constant N.sub.2 flow (60 mL min.sup.−1).
[0272] Scanning electron microscopy (SEM). Micrographs of as-produced and sintered thin films are taken using JSM-IT300HR In Touch Scope SEM (JEOL USA, Inc.) For imaging purpose, thin films are fractured, and powders are used as is. SPI sputter coater (SPI Supplies, Inc.) is used to sputter coat all the samples with gold and palladium.
[0273] X-Ray diffraction (XRD). As-produced powders and sintered films are characterized using Rigaku Rotating Anode Goniometer (Rigaku Denki., LTD., Tokyo, Japan). For data collection, as-produced powders are prepared by placing ˜100 mg in XRD sample holders. Cu Kα (λ=1.54 Å) radiation operating at working voltage of 40 kV and current of 100 mA is used. Scans are continuous from 10 to 70° 2θ using a scan rate of 5 min.sup.−1 in 0.01 increments. The presence of crystallographic phases, and their wt. fraction is determined by using Jade program 2010 (Version 1.1.5 from Materials Data, Inc.).
[0274] FTIR Spectra analyses are run on Nicolet 6700 Series FTIR spectrometer (Thermo Fisher Scientific, Inc.) and are used to measure FTIR spectra. 1 wt. % of the samples are mixed with KBr (International Crystal Laboratories); the mixtures are ground rigorously with an alumina mortal pestle; and the dilute samples are packed in the sample holder to be analyzed. Prior to data acquisition in the range of 4000-400 cm.sup.−1, the sample chamber is purged with N.sub.2.
[0275] GPC analyses is done on a Waters 440 system equipped with Waters Styragel columns (7.8×300, HT 0.5, 2, 3, 4) with RI detection using an Optilab DSP interferometric refractometer and THF as solvent. The system is calibrated using polystyrene standards. Analyses are performed using Empower 3 Chromatography Data Software (Waters, Corp., Milford, Mass.).
[0276] MALDI-TOF is done on Bruker AutoFlex Speed using poly(ethylene glycol) as a calibration standard, trihydroxyanthracene as the matrix and AgNO.sub.3 as the ion source. Samples are prepared by mixing solutions of 5 parts matrix (10 mg mL.sup.−1 in THF), 5 parts sample (1 mg mL.sup.−1 in THF), and optionally 1 part AgNO.sub.3 (1.0 mg mL.sup.−1 in THF) and blotting the mixture on the target plate.
[0277] AC Impedance data is collected with broadband dielectric spectrometer (Biologics) in a frequency range of 7 MHz to 1 Hz at −35 to 80° C. in increments of 10° C. Concentric gold electrodes, 3 mm in diameter, are deposited using a SPI sputter coater on both surfaces of the films using a deposition mask. “EIS spectrum analyser” software is used for extracting total resistance. Equivalent circuit consisting of (R.sub.totalQ.sub.total)(Q.sub.electrode) is used. R and Q denote resistance and constant phase element, respectively. SEM fracture surface images are taken to measure sample thicknesses.
Example 1
[0278] Synthesis of PON from Phosphoramide.
[0279] In a 200 mL round bottom Schlenk flask, placed in an ice bath and under N.sub.2(g), NaNH.sub.2 (7.0 g, 0.179 mol) is added to 80 mL of distilled THF. OPCl.sub.3 (5.0 mL, 53.6 mmol) is then added with a graduated pipette to form a reaction mixture. The ice bath is removed after 1 d of reaction and the reaction was kept running at room temperature under N.sub.2 for 1 week. The reaction mixture remains cloudy due to insoluble NaCl byproduct. Thereafter, the soluble and insoluble parts in the reaction mixture are separated by centrifugation. This results into 50 mL of stable suspension. To obtain the yield of the reaction, a small sample (3 mL) was taken from the solution and vacuum dried at 60° C. on a Schlenk line. The product is a yellow solid with a yield of 0.23 g, the total yield would be 3.8 g, which is about 75% of theoretical yield (5.1 g)
[0280] PON Precursor.
[0281]
[0282] PON precursor is heated to different temperatures under N.sub.2.
[0283] Table below shows the typical FT-IR of PON and LiPON phases.
TABLE-US-00002 TABLE 2 Typical FT-IR of PON and LiPON phases. Phase IR bands Wavenumber, cm.sup.−1 PON P—N═P 1300 P—O—P 1010 P—O/P—N 900-1100 NH.sub.4.sup.+ 1400 N—H ~3400 LiPON P═O 1150-1300 P—O.sup.— 950-1150 P—O—P/P—N═P 850-950 —NH.sub.2/—NH ~3400 Li—O—P 450-550, 850-925, 1450-1500
[0284]
[0285]
[0286]
[0287] Based on the structures shown in
TABLE-US-00003 TABLE 3 Possible compositions of PON precursor. m/z, Da Possible compositions 583 2A + 2C = 588.0 611 5A + C + —H = 607.0 825 6A + B + C + —H = 824.0 897 7A + B + C + —H = 902 1041 7A + 2B + C + —H = 1041
[0288]
Example 2
[0289] Synthesis of LixPON.
[0290] Li.sub.3PON precursor: Following the synthesis of PON precursor, LiNH.sub.2 (3.0 g, 0.13 mol, the calculated amount of —NH in the PON precursor) is added to the suspension of PON precursor [O═P(NH.sub.2).sub.3] under N.sub.2 while an ice bath is attached. The mixture became cloudy after adding LiNH.sub.2 as it is not very soluble in THF. This is all performed under N.sub.2. The mixture is kept stirring magnetically under N.sub.1. The ice bath is removed after 1 d of reaction.
[0291] After a week of reacting, soluble and insoluble parts in the reaction mixture again are separated by centrifugation. This results in 30 mL of a yellow stable suspension. The yield is about 4 g (about 90% of theoretical yield).
[0292] Similarly, Li.sub.6PON precursor can be synthesized with double the amount of
[0293]
[0294] The source of the νO—H band is unknown. Two possible explanations are that it comes from equilibria between N—H/P═O<->N═P and O—H, or from excess unreacted LiNH.sub.2 which reacts with moisture to become LiOH.
[0295]
[0296] Based on the structures shown in
TABLE-US-00004 TABLE 5 Possible compositions of Li.sub.xPON precursors. Li.sub.3PON Li.sub.6PON m/z, Da Possible compositions m/z, Da Possible compositions 587 A.sub.2 + 2A.sub.3 + 2B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 3A.sub.3 + B.sub.3 + 579 4A.sub.1 + 2A.sub.2 + A.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 579.9 B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 587.4 699 A.sub.1 + B.sub.1 + 3B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = A.sub.1 + B.sub.2 + 706 4A.sub.1 + A.sub.2 + B.sub.2 + B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 707.8 B.sub.3 + 2B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 697.5 A.sub.2 + 6A.sub.3 + B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 700.2 713 3A.sub.1 + 3B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 2A.sub.1 + A.sub.2 + 712 4B.sub.1 + B.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 711.0 C.sub.3 + 2C.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 714.5 6A.sub.1 + A.sub.2 + B.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 713.0 837 A.sub.1 + 2B.sub.1 + 3B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 836.5 718 3B.sub.1 + 2B.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 716.9 6A.sub.1 + A.sub.2 + B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 718.9 923 3A.sub.1 + 2A.sub.2 + A.sub.3 + 2B.sub.1 + B.sub.2 + —H + —NH.sub.2 − 761 A.sub.2 + 4A.sub.3 + B.sub.3 + B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 761.2 Li.sup.+ = 924.7 937 2A.sub.1 + 2A.sub.2 + 2A.sub.3 + 2B.sub.1 + B.sub.2 + —H + —NH.sub.2 − 767 A.sub.2 + 4A.sub.3 + 2B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 767.1 Li.sup.+ = 936.7 1147 3A.sub.1 + 2A.sub.2 + 2B.sub.1 + B.sub.2 + 2B.sub.4 + —H + —NH.sub.2 − 944 A.sub.1 + 3A.sub.3 + 2B.sub.1 + B.sub.3 + B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = Li.sup.+ = 1148.5 943.4 1371 3A.sub.1 + 3A.sub.2 + 3B.sub.1 + B.sub.2 + 2B.sub.4 + —H + —NH.sub.2 − 1000 A.sub.2 + 2A.sub.3 + 3B.sub.1 + B.sub.3 + B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = Li.sup.+ = 1371.4 998.4 5B.sub.1 + B.sub.2 + B.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 1000.8 1384 A.sub.1 + A.sub.2 + 11A.sub.3 + 2B.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 1902 12A.sub.1 + 5A.sub.2 + A.sub.3 + B.sub.1 + B.sub.3 + B.sub.4 + —H + —NH.sub.2 − 1384.4 Li.sup.+ = 1902.4
Example 3
[0297] Synthesis of SiPON.
[0298] In a 200 ml round bottom Schlenk flask, 80 ml of distilled THF is first collected. (Me.sub.3Si).sub.2NH (20.1 ml, 96.6 mmol) and OPCl.sub.3 (5.0 ml, 53.6 mmol) are then added via graduated pipettes. All was done in an ice bath under N.sub.2. Initially, the reaction mixture is transparent. After 5-10 min of stirring, insoluble solid started to form from the reaction and the mixture became cloudy. The ice bath was removed after 1 d of reacting and the reaction was kept running at 40° C. under N.sub.2 for 1 week.
[0299] After a week of reacting, the soluble and insoluble parts in the reaction mixture are separated by centrifugation. This results in 60 ml of a transparent solution. A small sample (3 mL) is taken from the solution and vacuum dried at 60° C. on a Schlenk line. The product is a yellow viscous liquid with a yield of 0.3 g, the total yield would be about 6 g, which is ˜95% of theoretical yield (6.3 g).
[0300] SiPON precursor.
[0301]
[0302] The spectra after heating to 800° C. are quite different, no νN—H band can be seen, suggesting that the volatile groups were eliminated by evaporation or particle decomposition. The final phase is the same as PON, with νP═O band at about 1250 cm.sup.−1, νP—O around 1000 cm.sup.−1.
[0303]
[0304]
[0305] Based on the structures showed in
TABLE-US-00005 TABLE 5 Possible compositions of SiPON precursor. m/z, Da Possible compositions 518 2B + E + —H = 517.4 582 A + B + C + E + —H = 584.2 656 2B + C + E + —H = 656.4 675 2A + 2B + E + —H = 673.4 720 B + 2C + F + —H = 717.3 804 3A + 2C + F + —H = 801.2 899 2A + 2B + F + —H = 895.8 940 2B + C + D + F + —H = 939.7 1088 3B + C + D + F + H = 1089.9 1150 A + B + 3D + F + —H = 1150.9
[0306]
Example 4
[0307] Synthesis of Li.sub.xSiPON.
[0308] Li.sub.3SiPON precursor: Following the synthesis of the SiPON precursor, LiNH.sub.2 (2.2 g, 95.8 mol, the calculated amount of —NH in the SiPON precursor) is then added to the SiPON precursor solution under N.sub.2 in an ice bath. The reaction mixture stays cloudy due to the low solubility of LiNH.sub.2. The ice bath is removed after 1 d of reacting. The reaction kept running at room temperature for 1-2 weeks or kept warming at 40° C. for 1 week.
[0309] Thereafter, the reaction mixture of Li.sub.3SiPON precursor is centrifuged to separate the liquid and solid parts. This results in a 50 mL of yellow transparent solution. The yield is about 6 g (about 90% of theoretical yield).
[0310] Similarly, Li.sub.6SiPON precursor can be synthesized with double amount of LiNH.sub.2.
[0311] Li.sub.xSiPON Precursors
[0312]
[0313]
[0314]
[0315] Based on the structures shown in
TABLE-US-00006 TABLE 6 Possible compositions of Li.sub.xSiPON precursors. Li.sub.3SiPON Li.sub.6SiPON m/z, Da Possible compositions m/z, Da Possible compositions 504 2A.sub.1 + 2A.sub.3 + C.sub.4 + —H + —NH.sub.2 − Li.sup.+ = A.sub.1 + 2A.sub.2 + 712 A.sub.1 + A.sub.2 + 6A.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 711.3 A.sub.3 + C.sub.4 + —H + —NH.sub.2 − Li.sup.+ = 502.7 3A.sub.1 + A.sub.2 + A.sub.3 + D.sub.3 + —H + —NHSiMe.sub.3 − Li.sup.+ = A.sub.2 + 2A.sub.3 + C.sub.4 + —H + —NHSiMe.sub.3 − Li.sup.+ = 502.8 713.2 511 A.sub.1 + 2C.sub.1 + C.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 511.0 718 8A.sub.1 + A.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 718.2 A.sub.1 + C.sub.1 + D.sub.1 + —H + —NHSiMe.sub.3 − Li.sup.+ = B.sub.1 + 5A.sub.1 + 2A.sub.2 + B.sub.1 + —H + —NH.sub.2 − Li.sup.+ = 718.3 2C.sub.1 + —H + —NHSiMe.sub.3 − Li.sup.+ = 510.5 519 2A.sub.1 + A.sub.2 + 3A.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 519.7 724 4A.sub.1 + 2A.sub.2 + A.sub.3 + C.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 724.8 2A.sub.2 + 2A.sub.3 + B.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 519.8 3A.sub.1 + A.sub.2 + 2A.sub.3 + C.sub.2 + —H + —NHSiMe.sub.3 − Li.sup.+ = 725.0 564 A.sub.1 + 2A.sub.3 + C.sub.3 + C.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 563.6 761 A.sub.1 + A.sub.2 + 3A.sub.3 + B.sub.3 + C.sub.4 + —H + —NH.sub.2 − Li.sup.+ = A.sub.2 + A.sub.3 + C.sub.3 + C.sub.4 + —H + —NHSiMe.sub.3 − Li.sup.+ = 760.5 563.8 625 A.sub.3 + B.sub.2 + C.sub.1 + C.sub.4 + —H + —NHSiMe.sub.3 − Li.sup.+ = 768 A.sub.1 + A.sub.2 + B.sub.1 + B.sub.2 + C.sub.1 + C.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 624.1 768.3 A.sub.2 + A.sub.3 + C.sub.1 + 2C.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 624.6 A.sub.1 + B.sub.2 + B.sub.3 + C.sub.1 + C.sub.3 + —H + —NHSiMe.sub.3 − Li.sup.+ = 768.4 699 A.sub.1 + 3A.sub.2 + 4A.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 699.5 962 5A.sub.1 + 3C.sub.1 + C.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 962.0 2A.sub.1 + B.sub.1 + 2C.sub.1 + C.sub.2 + D.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 962.2 707 3A.sub.1 + 2A.sub.2 + D.sub.3 + —H + —NHSiMe.sub.3 − Li.sup.+ = 968 2A.sub.1 + A.sub.2 + B.sub.2 + 3C.sub.1 + C.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 707.3 968.1 2A.sub.1 + B.sub.2 + 2C.sub.1 + C.sub.2 + D.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 968.2 713 2A.sub.1 + 2A.sub.2 + A.sub.3 + C.sub.1 + C.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 1013 A.sub.1 + 3C.sub.1 + 2C.sub.2 + D.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 713.8 1012.0 728 2A.sub.1 + 3C.sub.1 + C.sub.2 + —H + —NH.sub.2 − Li.sup.+ = Ai + 2C.sub.1 + 1212 2A.sub.1 + A.sub.2 + 6A.sub.3 + 2C.sub.1 + C.sub.2 + —H + —NH.sub.2 − Li.sup.+ = C.sub.2 + D.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 728.0 1212.2 B.sub.1 + 2C.sub.1 + 2C.sub.2 + —H + —NH.sub.2 − Li.sup.+ = A.sub.1 + 2C.sub.1 + C.sub.3 + D1 + —H + —NH.sub.2 − Li.sup.+ = 728.2 945 3A.sub.1 + 4C.sub.1 + C.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 945.0 1257 3A.sub.1 + B.sub.1 + B.sub.3 + 4C.sub.1 + C.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 1257.3 952 11A.sub.1 + A.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 952.2 1456 A.sub.1 + A.sub.2 + 4A.sub.3 + 3C.sub.1 + 2C.sub.2 + D.sub.2 + —H + −NH.sub.2 − 6A.sub.1 + 2A.sub.2 + B.sub.1 + B.sub.2 + —H + —NH.sub.2 − Li.sup.+ = 952.4 Li.sup.+ = 1455.5 2A.sub.1 + 2A.sub.2 + 10A.sub.3 + D.sub.3 + —H + —NH.sub.2 − Li.sup.+ = 1455.8
Example 5
[0316] Synthesis of SiPHN.
[0317] In a 200 mL round bottom Schlenk flask, 80 mL of distilled THF is first collected, Cl.sub.6N.sub.3P.sub.3 (7.5 g, 21.6 mmol) and NH(SiMe.sub.3).sub.2 (29.2 mL, 0.14 mol) are added. The ratio of Cl.sub.6N.sub.3P.sub.3 to NH(SiMe.sub.3).sub.2 is 1:6.5. All is done in an ice bath under N.sub.2. Cl.sub.6N.sub.3P.sub.3 is mainly soluble in THF, after adding with NH(SiMe.sub.3).sub.2, the reaction is cloudy. However, the mixture slowly turns transparent and the color turns yellow after reacting overnight, which suggests that a soluble product forms during the reaction. The reaction is kept running at 40° C. under N.sub.2 for 1 week.
[0318] Thereafter, the reaction mixture of SiPHN precursor is centrifuged to separate the liquid and solid parts. This results into 65 mL of a yellow solution. A small sample (3 mL) is taken from the solution and vacuum dried at 60° C. on a Schlenk line. The product is a yellow viscous liquid with a yield of 0.53 g. The total yield would be 11.4 g, which is ˜80% of theoretical yield (14.3 g).
[0319] SiPHN Precursor
[0320]
[0321]
[0322]
Example 6
[0323] Synthesis of LiSiPHN.
[0324] Following the synthesis of SiPHN precursor, LiNH.sub.2 (3.0 g, 0.13 mol, the calculated amount of —NH in the SiPHN precursor) is added to the SiPHN precursor solution under N.sub.2 in an ice bath, no bubbles are generated from the reaction. The reaction mixture stays cloudy due to the low solubility of LiNH.sub.2. After 1 d of reacting, the ice bath is removed and changed to an oil bath for heating. The color of the reaction mixture becomes orange. The reaction is kept running at 40° C. under N.sub.2 for a week.
[0325] Thereafter, the reaction mixture of LiSiPHN precursor is centrifuged to separate the liquid and solid parts. This results in 60 mL of an orange solution. A small sample (3 mL) is taken from the solution and vacuum dried at 60° C. on a Schlenk line. The product is a 0.5 g brown solid. The total yield is calculated to be 10 g, which is 83% of the theoretical yield (12 g).
[0326] Li SiPHN Precursors
[0327]
[0328]
[0329]
[0330] Based on the structures shown in
TABLE-US-00007 TABLE 7 Possible compositions of LiSiPHN precursors. m/z, Da Possible compositions 708 C.sub.2 + C.sub.4 + D.sub.2 − Li.sup.+ = 707.0 714 2C.sub.3 + D.sub.3 + —H − Li.sup.+ = C.sub.2 + C.sub.4 + D.sub.3 − Li.sup.+ = 712.9 720 C.sub.3 + C.sub.4 + D.sub.3 − Li.sup.+ = 718.8 726 2C.sub.4 + D.sub.3 − Li.sup.+ = 726.8 762 2C.sub.1 + C.sub.3 + H − Li.sup.+ = C.sub.1 + 2C.sub.2 − Li.sup.+ = 761.4 768 A.sub.4 + D.sub.1 − Li.sup.+ = A.sub.3 + D.sub.2 − Li.sup.+ = 765.7 B.sub.3 + C.sub.3 + —H + —NHSiMe.sub.3 − Li.sup.+ = B.sub.4 + C.sub.2 + —H + —NHSiMe.sub.3 − Li.sup.+ = 771.8 952 A.sub.6 + C.sub.3 + —NHSiMe.sub.3 − Li.sup.+ = B.sub.4 + B.sub.5 + —NHSiMe.sub.3 − Li.sup.+ = 950.9 B.sub.3 + C.sub.3 + C.sub.4 − —H − Li.sup.+ = B.sub.5 + C.sub.2 + C.sub.5 − —H − Li.sup.+ = 952.4 958 C.sub.1 + C.sub.3 + C.sub.4 + D.sub.1 − Li.sup.+ = C.sub.1 + C.sub.2 + C.sub.4 + D.sub.2 − Li.sup.+ = 959.2 964 C.sub.2 + C.sub.3 + C.sub.4 + D.sub.1 − Li.sup.+ = 965.1 970 3C.sub.3 + D.sub.2 − Li.sup.+ = 970.0 1015 A.sub.1 + C.sub.3 + D.sub.1 + H − Li.sup.+ = B.sub.1 + C.sub.1 + C.sub.3 + —H + —NHSiMe.sub.3 − Li.sup.+ = 1012.0 A.sub.1 + C.sub.2 + D.sub.3 − Li.sup.+ = B.sub.1 + B.sub.3 + D.sub.2 − Li.sup.+ = 1016.9 1214 A.sub.5 + B.sub.4 + D.sub.3 + —H − Li.sup.+ = A.sub.5 + B.sub.5 + D.sub.2 − Li.sup.+ = 1214.9 1457 A.sub.2 + B.sub.4 + C.sub.3 + D.sub.2 + H − Li.sup.+ = A.sub.3 + C.sub.1 + C.sub.3 + C.sub.4 + —NHSiMe.sub.3 − Li.sup.+ = B.sub.1 + B.sub.5 + C.sub.1 + C.sub.4 − —H + —NHSiMe.sub.3 − Li.sup.+ = 1455.2
Example 7
[0331] Synthesis of Na.sub.3SiPON.
[0332] NaNH.sub.2 (3.8 g, 0.1 mol, equivalent amount of —NH) is added to the solution of SiPON precursor under N.sub.2 in an ice bath. A lot of bubbles form from the reaction right after adding NaNH.sub.2. The mixture turns yellow after 1 d of reacting.
[0333] Na.sub.3SiPON precursor
[0334] A small sample of the liquid from the Na.sub.3SiPON solution is taken and vacuum dried at 40° C. on a Schlenk line. It is then heated to 180° C. under vacuum for 1 h. The product is a brown solid. TGA and FTIR studies are run on the brown solid.
[0335] FTIR shows a band at about 3000 cm.sup.−1, assigned to νN—H. The sharp peak at 1400 cm.sup.−1 is typical for NH.sub.4.sup.+ (ammonium ions). The peaks near 1200 and 900 cm.sup.−1 can be assigned to νP═O and νP—O—P/P—N═P respectively. No peak for νO—H is observed.
[0336]
[0337] The residue is a dark solid.
Example 8
[0338] Synthesis of Li2NaPON.
[0339] In a 50 ml round bottom Schlenk flask, NaNH.sub.2 (3.5 g, 0.09 mol) is first added to 30 ml of distilled THF. Then OPCl.sub.3 (2.5 ml, 0.027 mol) is added with a graduated pipette. All was done in an ice bath under N.sub.2. The reaction mixture started to generate bubbles after about 1 min of adding OPCl.sub.3, which may be caused by heat generated from the reaction. The mixture also becomes yellow soon after bubbling, showing that reaction is taking place. The ice bath is removed after 1 d of reaction.
[0340] After a week of reaction, the soluble and insoluble parts in the reaction mixture are separated by centrifugation. The liquid is an orange solution.
[0341] Thereafter, the solution part is taken into another 50 ml Schlenk flask for synthesizing Li.sub.2NaPON. LiNH.sub.2 (0.74 g, 32.2 mmol) and NaNH.sub.2 (0.63 g, 16.1 mmol) are added to the solution under N.sub.2 in an ice bath. Bubbles start to generate from the reaction mixture a few seconds after adding the LiNH.sub.2 and NaNH.sub.2. The reaction mixture stays orange.
[0342] Li.sub.2NaSiPON precursor
[0343] A small sample of the liquid from the Li.sub.2NaPON solution is taken and vacuum dried at 40° C. on a Schlenk line. It is then heated to 180° C. under vacuum for 1 h. The product is a brown solid. TGA and FTIR studies are run on the brown solid.
[0344]
[0345]
[0346] The residue after TGA is a black solid.
Example 9
[0347] Thin Film Substrate Synthesis.
[0348] LiAlO.sub.2 Powder Synthesis
[0349] LiAlO.sub.2 nanopowders (NPs) are generated by using liquid flame spray pyrolysis (LF-FSP) apparatus. Lithium propionate and alumatrane are quantitatively mixed at selected molar ratios to result in LiAlO.sub.2 composition with 80, 150, and 300 wt. % excess lithium, hereafter referred as LiAlO.sub.2+80%, LiAlO.sub.2+150% and LiAlO.sub.2+300%, respectively. Table 8 shows the number of precursors used for each composition, which are dissolved in ethanol. Resulting NPs are Li short arising from volatility of Li.sub.2O from flame temperatures above 1000° C. Hence, excess lithium propionate is introduced to result in a phase pure material. The resulting precursor mixture is dissolved in ethanol to give a 3 wt % ceramic yield solution and the solution is aerosolized with oxygen into a 1.5 m long combustion chamber where it is ignited using methane/oxygen pilot torches. After combustion and cooling, produced NPs are collected downstream in rod-in-tube electrostatic precipitators (ESP) operated at 10 kV.
TABLE-US-00008 TABLE 8 Amount of precursors dissolved in ethanol (2100 mL). LiO.sub.2CCH.sub.2CH.sub.3 (g) Al[OCH(CH.sub.3)CH.sub.2CH.sub.3].sub.3 (g) LiAlO.sub.2 + 80% 49.63 455.35 LiAlO.sub.2 + 150% 69 455.35 LiAlO.sub.2 + 300% 82.72 455.35
[0350] As-produced produced LiAlO.sub.2 nanopowders (10 g, 0.15 mol) are first dispersed in anhydrous ethanol (350 ml) with 2 wt % polyacrylic acid (200 mg, 1.2 mmol) dispersant, using an ultrasonic horn (Vibra-cell VC 505 Sonics & Mater. Inc.) at 100 W for 10 min. The suspension is left to settle for 4 h to allow larger particles to settle. The supernatant is decanted, and the recovered solution is poured into a clean beaker and left to dry overnight in the oven (60° C.). The dried powders are ground in an alumina mortar and pestle.
[0351] Thin Film Substrate Processing
[0352] A suspension is made by dissolving collected nanopowder (0.7 g), benzyl butyl phthalate (0.13 g), as a plasticizer, poly acrylic acid (0.01 g) as a dispersant, polyvinyl butyral (0.13 g) as a binder in anhydrous ethanol (0.9 ml) and acetone (0.9 ml) to form a mixture. The mixture (2.39 g) is placed in a 20 mL vial and milled with spherical alumina beads (6 g) with 3 mm diameter media overnight to homogenize the suspension. The suspension is cast using a wire wound rod coater (Automatic Film Applicator 1137, Sheen Instrument, Ltd). After solvent evaporation, dried green films are uniaxially pressed in between stainless-steel dies at 100° C. with a pressure of 50-70 MPa for 5 min using a heated bench (Carver, Inc) top press to improve packing density.
[0353] Sintering Studies
[0354] Heat treatments are conducted in a High-Temperature Vaccum/Gas tube furnace (Richmond, Calif.). Green films of LiAlO.sub.2+80%, LiAlO.sub.2+150%, and LiAlO.sub.2+300% are placed between alumina disks and sintered to 1100° C. for 2 h in air (100 mL min.sup.−1).
[0355] LATSP (Li.sub.1.7Al.sub.0.3Ti.sub.1.7Si.sub.0.4P.sub.2.6O.sub.12) and LiAlO.sub.2 substrates are synthesized. Green films of LATSP are placed in between alumina plates and debindered/crystallized at 665° C./2 h at a ramp rate of 5° C. min.sup.−1 followed by sintering at 1000° C./1 h at a ramp rate of 1° C. min.sup.−1 under 120 ml min.sup.−1 air flow.
[0356] Coating Studies
[0357] Sintered substrates are dip-coated 1× in the desired precursor (LiPON, a are left to dry for 12 h under vacuum at 100° C. Dried samples were then heated up to selected temperature and atmosphere as shown in
Example 10
[0358] Coating LATSP with PON, SiPON, Li.sub.3PON, Li.sub.1.5SiPON, Li.sub.3SiPON, Li.sub.6SiPON.
[0359] LATSP substrates are dip-coated 1× in PON, SiPON, Li.sub.3PON, Li.sub.1.5SiPON, Li.sub.3SiPON, Li.sub.6SiPON solutions using copper wire to suspend the sample. The coated substrates are left to dry for 12 h/vacuum/100° C. Dried samples are then heated to 300, 400, 500 and 600° C./2 h/N.sub.2 at a ramp rate of 5° C./min as shown in
[0360]
[0361]
[0362] LATSP substrates coated with SiPON and heated to 400° and 600° C. did not show a clear distinguished coating interface. These heating schedules lead to a poor coating for both PON and SiPON precursors. Substrates treated to 500° C. showed coating with an average thickness of 6.8 μm.
[0363] LATSP+Li.sub.3PON films heated to 500° C. did not show coating interface this might be ascribed to poor coating. However, there is a clear distinguished interface between the coating and the substrate for samples heated to 600° C. with an average coating thickness of 8.8 μm.
[0364]
[0365] Coating treatments with Li.sub.3SiPON and Li.sub.6SiPON solutions at 500° C. do not show uniform interfaces as they are scarcely distributed. The inconstancy of coating thickness might be ascribed to the uncontrolled process of dip-coating. LATSP substrates coated with Li.sub.3SiPON and Li.sub.6SiPON and heated to 500° C. show porous coating interfaces suggesting that the coatings are not stable at higher temperatures.
[0366] From the fracture surface image of LATSP+ Li.sub.6SiPON films heated to 400° C., the coating seems to be percolating through the grain and grain boundaries represented by the white colors. The coating also appears on the surface of the film with an average thickness of 5 μm. All LATSP substrates coated with Li.sub.xSiPON derivatives and heated to 600° C. show interfaces with island morphologies. The coatings are not uniformly distributed; suggesting that 600° C. might be too high a temperature for Li.sub.xSiPON derivatives on LATSP substrates.
[0367]
[0368]
[0369]
TABLE-US-00009 TABLE 9 Conductivities (σ.sub.t) of LATSP films coated with polymers at selected temperatures. Polymer Temperature σ RT Film substrate coating (° C./2 h/N.sub.2) (S/cm) LATSP PON 400 5.4 × 10.sup.−5 ± 6 × 10.sup.−5 500 7 × 10.sup.−7 ± 3 × 10.sup.−7 600 3.2 × 10.sup.−6 ± 2.3 × 10.sup.−6 LATSP SiPON 400 6.3 × 10.sup.−5 ± 4.2 × 10.sup.−5 500 3 × 10.sup.−8 ± 1.2 × 10.sup.−5 600 6.3 × 10.sup.−6 ± 2.7 × 10.sup.−6 LATSP Li.sub.3PON 400 3 × 10.sup.−5 ± 1.5 × 10.sup.−5 500 3 × 10.sup.−5 ± 9.1 × 10.sup.−6 600 3.3 × 10.sup.−5 ± 7.6 × 10.sup.−6 LATSP Li.sub.1.5SiPON 400 4.5 × 10.sup.−5 ± 3.1 × 10.sup.−5 500 5.3 × 10.sup.−8 ± 2.7 × 10.sup.−8 600 2.3 × 10.sup.−6 ± 1.4 × 10.sup.−6 LATSP Li.sub.3SiPON 400 6.7 × 10.sup.−5 ± 3.8 × 10.sup.−5 500 5.2 × 10.sup.−5 ± 3.8 × 10.sup.−6 600 1.92 × 10.sup.−5 ± 1.2 × 10.sup.−5 LATSP Li.sub.6SiPON 400 3.3 × 10.sup.−5 ± 1 × 10.sup.−5 500 1 × 10.sup.−5 ± 9.8 × 10.sup.−6 600 2.5 × 10.sup.−6 ± 2.6 × 10.sup.−6
[0370] Table 9 illustrates the total conductivity of LATSP substrates coated with different precursor solutions and heated to 400, 500, and 600° C./2 h/N.sub.2. LATSP substrates coated with PON and SiPON show the highest conductivity when heat-treated at 400° C. This might be attributed to the fact that the coating is minimal and is not visible from the fracture surface images shown in
[0371] Increasing the heating temperature leads to improved conductivity for Li.sub.3PON coatings. The highest conductivity is when samples are heated to 600° C. This heating schedule also leads to good bonding interfaces.
[0372] Li.sub.1.5SiPON film shows poor conductivity when heat treated to 500° C. and 600° C. due to the porous coating. This solution is not stable in air for coating, thus the resulting substrates suffer from too thick coatings that resulted in poor ionic conductivity.
[0373] The Li.sub.3SiPON and Li.sub.6SiPON solutions give the best conductivity around 400°-500° C. The coatings are not stable when heated to 600° C. as shown by the SEM images in
[0374]
Example 11
[0375] Coating LiAlO.sub.2+X with PON, SiPON, Li.sub.3PON, Li.sub.1.5SiPON, Li.sub.3SiPON, Li.sub.6SiPON.
[0376] LiAlO.sub.2+X substrates are placed between α-alumina disks and heated at 665° C. for 2 h at a ramp rate of 3° C. min.sup.−1 followed by sintering to 1100° C./2 h at a ramp rate of 1° C. min.sup.−1 in air (100 ml min.sup.−1).
[0377] LiAlO.sub.2+X substrates are dip-coated for 1 min in PON, SiPON, Li.sub.3PON, Li.sub.1.5SiPON Li.sub.3SiPON, and Li.sub.6SiPON solutions (3 mL). The coated films are left to dry for 12 h under vacuum at 100° C. Dried samples are then heated up to 500° and 600° C./2 h/N.sub.2 at a ramp rate of 1° C./min.
[0378]
[0379] LiAlO.sub.2+300%+Li.sub.3PON films heated to 400° C. show a clear distinguished interface. However, on heating temperature to 500° C. and 600° C., the coating fades and delaminates as demonstrated from the SEM fracture surface images suggesting that the coating is not stable above 400° C.
[0380]
[0381] The Li.sub.6SiPON films heated to 400° C. give porous coatings; however, at 500° C. the coatings are uniform and dense. The bottom part of the substrate did not coat well because a Teflon substrate used to place the films after the dip coating process results in loss of the coating. The Li.sub.6SiPON coating is not stable above 500° C. on LATSP and LiAlO.sub.2+300% substrates.
[0382]
TABLE-US-00010 TABLE 10 Conductivities (σ.sub.t) of LiAlO.sub.2 + v300% films coated with polymers at selected temperatures. Polymer Temperature σ RT Film substrate coating (° C./2 h/N.sub.2) (S/cm) LiAlO.sub.2 + 300% PON 400 8 × 10.sup.−7 ± 2 × 10.sup.−7 500 1.4 × 10.sup.−7 ± 1.5 × 10.sup.−7 600 1.4 × 10.sup.−8 ± 0.3 × 10.sup.−8 LiAlO.sub.2 + 300% SiPON 400 4.7 × 10.sup.−5 ± 1.2 × 10.sup.−5 500 N/A 600 2 × 10.sup.−7 ± 8.4 × 10.sup.−8 LiAlO.sub.2 + 300% Li.sub.3PON 400 2.7 × 10.sup.−5 ± 1.1 × 10.sup.−5 500 1.2 × 10.sup.−5 ± 0.5 × 10.sup.−5 600 1 × 10.sup.−7 ± 4.7 × 10.sup.−8 LiAlO.sub.2 + 300% Li.sub.1.5SiPON 400 3.2 × 10.sup.−8 ± 1.5 × 10.sup.−5 500 8.9 × 10.sup.−8 ± 2.6 × 10.sup.−8 600 7.1 × 10.sup.−6 LiAlO.sub.2 + 300% Li.sub.3SiPON 400 1.8 × 10.sup.−5 ± 3.5 × 10.sup.−5 500 7 × 10.sup.−5 ± 1.3 × 10.sup.−5 600 4.7 × 10.sup.−5 ± 0.8 × 10.sup.−5 LiAlO.sub.2 + 300% Li.sub.6SiPON 400 1.4 × 10.sup.−4 ± 5.2 × 10.sup.−5 500 1.3 × 10.sup.−5 ± 2.1 × 10.sup.−5 600 1.8 × 10.sup.−5 ± 1.7 × 10.sup.−5
[0383] Table 10 records the total conductivity of LiAlO.sub.2+300% substrates coated with different precursor solutions and heated to 400, 500, and 600° C./2 h/N.sub.2. LiAlO.sub.2+300% substrates coated with PON and SiPON show the highest conductivities when heat treated at 400° C. with a minimal coating of both precursors, which was also demonstrated when using LATSP substrate. The impedance starts to increase on heating to 500° C. and 600° C., a result of too thick coating for PON thin films. Since these coatings percolate into the substrate when treated to 600° C., the resulting conductivities are poor.
[0384] The Li.sub.3PON thin films show inverse behavior when LiAlO.sub.2+300% is used versus the LATSP substrate. The impedance decreases on heating from 400° C. to 600° C. by two orders of magnitude. This can be attributed to the fact that the coating is not stable at high temperatures; as demonstrated from the delamination of the coating from the
[0385] The Li.sub.1.5SiPON films shows poor conductivity on heat treating to 400° C. In fact, there is an appearance of a parallel combination of a resistance and a capacitance upon the complex plane as the impedance go all the way down to the real axis at low frequencies. However, the conductivity seems to improve at 600° C.
[0386] The Li.sub.3SiPON films show conductivity (10.sup.−5 S/cm) on heat treating from 400° to 600° C. consistent with the LATSP substrate as well as LiAlO.sub.2+300%.
[0387] The Li.sub.6SiPON solution gives the highest conductivity of 1.4×10.sup.−∝+5.2×10.sup.−5 S/cm for LiAlO.sub.2+300% substrates. The substrate without a coating has a conductivity of 1.6×10.sup.−8 S/cm. However, the conductivity drops an order of magnitude when the film is heated above 400° C.
[0388]
[0389]
[0390] Tables 11 and 12 illustrate the total conductivity of LiAlO.sub.2+Li.sub.3SiPON coated substrates heated to 300° C. and 400° C./2 h/N.sub.2 respectively. Samples treated at higher temperatures show higher conductivities than samples treated at 300° C. This suggests the coating is more stable at 400° C. The total conductivities reported here are three to four orders of magnitude higher than LiAlO.sub.2 substrates without the coating.
TABLE-US-00011 TABLE 11 Total conductivities (σ.sub.t) of LiAlO.sub.2v + Li.sub.3SiPON heated to 300° C./2 h/N.sub.2 samples at selected temperatures. T (° C.) σ(S cm.sup.−1) −20 7.28 × 10.sup.−5 −10 9.26 × 10.sup.−4 25 1.43 × 10.sup.−4 35 1.38 × 10.sup.−4 45 2.55 × 10.sup.−4 65 4.25 × 10.sup.−4 85 5.66 × 10.sup.−4
TABLE-US-00012 TABLE 12 Total conductivities (σ.sub.t) of LiAlO.sub.2 + Li.sub.3SiPON samples heated to 400° C./2 h/N.sub.2 at selected temperatures. T (° C.) σ(S cm.sup.−1) −20 1.35 × 10.sup.−4 −100 2.24 × 10.sup.−4 25 3.67 × 10.sup.−4 7.21 × 10.sup.−4 35 7.89 × 10.sup.−4 45 8.75 × 10.sup.−4 65 9.81 × 10.sup.−4 85 1.02 × 10.sup.−3
Example 12
[0391] Coating α-Al.sub.2O.sub.3 with Li.sub.3PON, Li.sub.3SiPON, Li.sub.6SiPON, Na.sub.3SiPON.
[0392] α-Al.sub.2O.sub.3 substrates are dip-coated for 1 min in Li.sub.3PON, Li.sub.1.5SiPON Li.sub.3SiPON, Li.sub.6SiPON, and Na.sub.3SiPON solutions (3 mL). The coated films are left to dry for 12 h under vacuum at 100° C. Dried samples were then heated up to 400-600° C./2 h/N.sub.2 at a ramp rate of 1° C./min.
[0393]
[0394] The Li.sub.6SiPON films heated to 400° C. show uniform and thin coatings bonded to the α-Al.sub.2O.sub.3 substrate. However, as the heating temperature increases the coating starts to become porous and delaminates from the substrate as seen for both LATSP and LiAlO.sub.2 substrates.
[0395]
TABLE-US-00013 TABLE 13 Total conductivities (σ.sub.t) of Al.sub.2O.sub.3 films coated with polymers at selected temperatures. Temperature σ RT Film substrate Polymer coating (° C./2 h/N.sub.2) (S/cm) Al.sub.2O.sub.3 Li.sub.3PON 400 1.2 × 10.sup.−4 500 7.1 × 10.sup.−5 600 1.7 × 10.sup.−5 Al.sub.2O.sub.3 Li.sub.3SiPON 400 3.5 × 10.sup.−8 500 2.3 × 10.sup.−5 600 5.8 × 10.sup.−6 Al.sub.2O.sub.3 Li.sub.6SiPON 400 4.7 × 10.sup.−5 500 1.1 × 10.sup.−4 600 8.8 × 10.sup.−6 Al.sub.2O.sub.3 Na.sub.3SiPON 400 2.3 × 10.sup.−8 500 2.3 × 10.sup.−6 600 1.7 × 10.sup.−6
Example 13
[0396] XRD studies of Li.sub.3PON and Li.sub.6SiPON.
[0397]
[0398]
Example 14
[0399] XPS Studies of Li.sub.3PON and Li.sub.6SiPON.
[0400] Previous XRD studies at 100° C. show mainly amorphous phase, hence the technique cannot detect the targeted elements and does not allow quantification of elemental composition nor the possibility to deduce elemental ratios. Hence XPS studies on the polymer precursors are performed.
[0401]
TABLE-US-00014 TABLE 14 Atomic ratios based on XPS analyses for Li.sub.3PON and Li.sub.6PON pellets. Ratio Li.sub.3PON Li.sub.6PON O/P 6 4.5 N/P 1.25 1.66 Li/N 2.68 3.5
[0402] XPS analysis also provides information about bonding environments. The O is peak is assigned to oxygen in Li—O—Li, P—O—P, and P═O bonds. XPS analysis indicates that the Li/N ratio increases from about 2.7 to about 3.5 when more LiNH.sub.2 is introduced to form Li.sub.6PON. The experimental N/P ratio is calculated to be 3, the found ratio from XPS analysis suggests nitrogen is lost during polymerization as suggested by the above condensation reactions. However, the N/P ratio (1.25-1.66) is much higher than reported for gas phase deposition techniques (0.92). XPS measurements further confirm that the Li.sub.3PON and Li.sub.6PON pellets contain 4.7 and 5.35 at. % of N.
[0403]
TABLE-US-00015 TABLE 15 Atomic ratios based on XPS analyses for Li.sub.3SiPON and Li.sub.6SiPON pellets. Ratio Li.sub.3SiPON Li.sub.6SiPON O/P 3.56 5.54 N/P 1.85 2.4 Li/N 1.43 1.68
[0404] The measured atomic composition shows that the Li/N ratio increases from about 1.43 to about 1.68 when more LiNH.sub.2 is introduced for Li.sub.6SiPON. However, the ratio is smaller than calculated for Li.sub.3PON (2.86) and Li.sub.6PON (3.5) pellets. It is likely that the introduction of silicon leads to loss of (Me.sub.3Si).sub.2N during condensation polymerization. The experimental ratio of N/P is calculated to be 3, the decrease in the ratio from XPS analysis suggests polymerization by the loss of nitrogen. However, the atomic percent of N is 8.5 and 6.7% for Li.sub.3SiPON and Li.sub.6SiPON, respectively. The N/P ratio (1.85-2.4) is still higher than what is reported for Li.sub.3PON and Li.sub.6PON in Table 15.
Example 15
[0405] PEO-Based Polymer Electrolytes.
[0406] The PEO polymer with molecular weights of 900 k are dissolved in acetonitrile (18 mL) and stirred magnetically under N.sub.2 until fully dissolved. Polymer precursors with weight ratios of 40 were mixed with the PEO/ACN solution and magnetically stirred for 24 hr. The PEO/precursor mixture is then cast on a Teflon plate. Solvent is allowed to evaporate at ambient for 24 h. The film is then dried under a vacuum of 3×10.sup.−3 Torr for 24 h at 65° C. Table 16 lists the amount of 60 wt. % PEO/precursor dissolved in 18 ml CAN.
TABLE-US-00016 TABLE 16 List of PEO and polymer electrolytes dissolved in 18 mL ACN. Mass of Mass of polymer Polymer Electrolyte PEO (g) electrolyte(g) Li.sub.3PON 0.6 0.21 Li.sub.6PON 0.6 0.14 Li.sub.2SiPHN 0.9 0.6 Li.sub.3SiPON 0.9 0.6 Li.sub.6SiPON 0.9 0.6
[0407] The PEO/polymer precursor ratio is chosen as 60:40 because this composition results in dense films easy to handle and process with optimal conductivity. Higher PEO concentrations result in poorer ionic conductivity while lower PEO concentrations result in poorer mechanical properties.
[0408]
[0409] XPS experiments are carried out on the polymer electrolytes on a Kratos Axis Ultra XPS system at room temperature under 3.1×10.sup.−8 Pa using a monochromatic Al source (14 kV and 8 mA). Binding energies of all the elements are calibrated relative to the gold Au 4f.sub.7/2 at 84 eV. All the data are analyzed by CASAXPS software using linear type background.
[0410]
TABLE-US-00017 TABLE 17 XPS analysis 60 PEO/Li.sub.6PON, Li.sub.2SiPHN, and Li.sub.6SiPON composite films. Position(eV) At. % Name Li.sub.6PON Li.sub.2SiPHN Li.sub.6SiPON Li.sub.6PON Li.sub.2SiPHN Li.sub.6SiPON Li 1s 52 52 53 7.88 4.44 5.2 P 2p 130 130 130 2.91 2.71 4.04 O 1s 529 529 529 22.58 23.68 25.37 N 1s 396 396 396 3.13 4.05 4.1 C 1s 280 285 283 63.5 62.44 60.26 Si 2p N/A 99 98 N/A 2.7 1.04
TABLE-US-00018 TABLE 18 Atomic ratios based on XPS analyses for 60 PEO/Li.sub.6PON, Li.sub.2SiPHN, and Li.sub.6SiPON composite films. Ratio Li.sub.6PON Li.sub.2SiPHN Li.sub.6SiPON N/P 1.07 1.49 1.01 Li/N 2.51 1.1 1.26
[0411] XPS analysis also provides information about elemental bonding environments. The N/P ratio (1.07-1.469) is still higher than what is reported by gas phase deposition techniques (0.92). The C is spectra could be deconvoluted into three Gaussian-Lorentzian mixed components. The binding energy of the carbon in all the polymer composite films coincides with the most intense carbon peak of PEO′ attributed to the carbon on the —CH.sub.2—CH.sub.2—O-repeat unit. The binding energy of C is is in the order of Li.sub.2SiPHN>Li.sub.6SiPON>Li.sub.6PON.
[0412]
[0413] XRD Studies of 60 PEO/Polymer Precurosr
[0414] The polymer composite electrolyte films, as well as pure PEO, are analyzed using a Rigaku rotating anode goniometer (Rigaku Denki., Ltd., Tokyo, Japan). XRD scans a made using the Cu Kα radiation (1.541 Å) operating at 40 kV and 100 mA in the 20 range of 10° to 40° and using a step width of 0.02°. The slower scan rate is used to minimize the signal-noise ratio.
[0415]
TABLE-US-00019 TABLE 19 Peak list, d-spacing, and intensity of pure PEO. 2-θ D Height FWHM Int. I Int. W Asym. No. (deg) (ang.) (cps) (deg) (cps deg) (deg) factor 1 19.376(4) 4.5773(10) 3447(107) 0.379(5) 1972(11) 0.57(2) 1.55(9) 2 23.522(5) 3.7792(9) 4197(118) 0.761(5) 4012(20) 0.96(3) 1.35(4) 3 26.452(15) 3.3668(19) 490(40) 0.54(2) 334(18) 0.68(9) 1.7(3)
[0416]
[0417] The X-ray spectrum of composite films exhibits peak shifts toward lower diffraction angle compared to pure PEO listed in Table 20. For example, the (112) peak shifts from 19.37° to 19.13° when Li.sub.3PON precursor was used. The d-spacing changes from 4.57 to 4.63 Å and this indicated that the distance between two planes (112) was enlarged when the polymer precursor is introduced. The shifting of X-ray peak can be caused by strain or stress. The possible reason for the peak shifting is the presence of the polymer precursor induces stresses that changed d-spacing of PEO crystals. The change could be an indicator of the stress transfer between the polymer precursor and the polymer chains. X-ray spectra data for PEO/LI.sub.6PON, PEO/Li.sub.2SiPHN, PEO/Li.sub.3SiPON, and PEO/Li.sub.6SiPON composites compared to pure PEO are listed in Tables 21-24, respectively.
TABLE-US-00020 TABLE 20 Peak list, d-spacing, and intensity of a 60 wt. % PEO/Li.sub.3PON composite film. D Height FWHM Int. I Int. W Asym. No. °2θ (ang.) (cps) (deg) (cps deg) (deg) factor 1 19.134(12) 4.635(3) 480(40) 0.284(16) 229(4) 0.48(5) 2.3(6) 2 23.278(14) 3.818(2) 594(44) 0.87(2) 804(7) 1.35(11) 1.85(15) 3 26.20(2) 3.398(3) 95(18) 1.25(5) 140(7) 1.5(3) 0.51(13) 4 29.387(12) 3.0368(12) 362(35) 0.139(9) 58(2) 0.16(2) 1.1(4)
TABLE-US-00021 TABLE 21 Peak list, d-spacing, and intensity of a 60 wt. % PEO/Li.sub.6PON composite film. D Height FWHM Int. I Int. W Asym. No. °2θ (ang.) (cps) (deg) (cps deg) (deg) factor 1 19.128(13) 4.636(3) 382(36) 0.314(15) 192(3) 0.50(6) 1.7(4) 2 23.310(15) 3.813(2) 604(45) 0.859(19) 801(7) 1.33(11) 2.01(18) 3 26.364(19) 3.378(2) 112(19) 1.35(5) 187(7) 1.7(4) 0.79(15) 4 29.404(18) 3.0351(18) 225(27) 0.158(18) 47(2) 0.21(4) 1.0(5)
TABLE-US-00022 TABLE 22 Peak list, d-spacing, and intensity of a 60 wt. % PEO/Li.sub.2SiPHN composite film. D Height FWHM Int. I Int. W Asym. No. °2θ (ang.) (cps) (deg) (cps deg) (deg) factor 1 19.15(2) 4.630(6) 135(21) 0.41(3) 84(3) 0.62(12) 1.6(4) 2 23.17(2) 3.836(4) 252(29) 0.94(2) 312(5) 1.24(16) 0.94(10) 3 26.25(2) 3.392(3) 47(12) 1.19(6) 59(3) 1.3(4) 0.53(7) 4 29.432(14) 3.0323(14) 278(30) 0.195(10) 60(3) 0.22(3) 1.8(5)
TABLE-US-00023 TABLE 23 Peak list, d-spacing, and intensity of a 60 wt. % PEO/Li.sub.3SiPON composite film. D Height FWHM Int. I Int. W Asym. No. °2θ (ang.) (cps) (deg) (cps deg) (deg) factor 1 19.286(13) 4.599(3) 68(15) 0.55(4) 47(3) 0.7(2) 0.9(3) 2 23.45(4) 3.790(6) 143(22) 0.89(4) 189(4) 1.3(2) 1.4(3)
TABLE-US-00024 TABLE 24 Peak list, d-spacing, and intensity of a 60 wt. % PEO/Li.sub.6SiPON composite film. D Height FWHM Int. I Int. W Asym. No. °2θ (ang.) (cps) (deg) (cps deg) (deg) factor 1 19.103(7) 4.6421(16) 448(39) 0.246(10) 175(4) 0.39(4) 1.02(12) 2 23.284(16) 3.817(3) 466(39) 0.77(2) 534(7) 1.15(11) 1.79(18) 3 26.18(5) 3.402(7) 65(15) 0.48(7) 48(5) 0.7(2) 1.6(10) 4 26.92(3) 3.309(4) 58(14) 0.30(8) 26(5) 0.45(19) 1.6(10)
[0418] The d-spacing for plane (112) is in increasing order of Li.sub.6SiPON>>Li.sub.6PON>>Li.sub.3PON>>Li.sub.2SiPHN>>Li.sub.3SiPON>>PEO
[0419] The d-spacing for plane (120) is in increasing order of Li.sub.2SiPHN>>Li.sub.3PON>>Li.sub.6S iP ON>>Li.sub.6PON>>Li.sub.3SiPON>>PEO
[0420] The d-spacing for plane (222) is in increasing order of Li.sub.6SiPON>>Li.sub.3PON>>Li.sub.2SiPHN>>Li.sub.6PON>>PEO.
[0421] The XRD pattern for 60 wt. % PEO/Li.sub.3SiPON does not show a peak for (222) plane, and it shows the lowest intensity compared to the other polymer precursor composite films. Hence, this composite polymer electrolyte showed the lowest crystallinity percentage.
[0422] Addition of the polymer precursors especially with Me.sub.3Si moieties decreases crystallinity of the polymer electrolyte considerably as demonstrated by broadening and reduction of PEO peak intensity as shown in
[0423]
TABLE-US-00025 TABLE 25 Total room temperature conductivity of PEO/precursors. Precursor Conductivity (S/cm) Li.sub.3PON 4.4 ± 0.6 × 10.sup.−4 Li.sub.6PON 3.7 ± 0.4 × 10.sup.−4 Li.sub.2SiPHN 1.1 ± 0.3 × 10.sup.−3 Li.sub.3SiPON 2.8 ± 0.2 × 10.sup.−3 Li.sub.6SiPON 2.7 ± 0.1 × 10.sup.−4
[0424] Table 25 summarizes the total room temperature resistivity of PEO/Li.sub.2SiPHN, Li.sub.3SiPON, and Li.sub.6SiPON composite films heated to 65° C./12 h/Vac. The PEO/Li.sub.3SiPON composite film shows the highest conductivity of 2.8 mS/cm when compared to the other polymer precursors. The PEO/precursor composite films 100 μm thick reveal decreases in PEO crystallinity as shown in the
[0425]
TABLE-US-00026 TABLE 26 Total conductivities (σ.sub.t) of 60 wt. % PEO/polymer precursor heated to selected temperatures. T σ(S cm.sup.−1) σ(S cm.sup.−1) σ(S cm.sup.−1) σ(S cm.sup.−1) (° C.) Li.sub.3PON Li.sub.6PON Li2SiPHN Li.sub.6SiPON −15 1.42 × 10.sup.−4 1.89 × 10.sup.−5 4.65 × 10.sup.−5 4.07 × 10.sup.−5 0 2.83 × 10.sup.−4 6.29 × 10.sup.−4 1.09 × 10.sup.−4 5.09 × 10.sup.−5 25 4.72 × 10.sup.−4 9.44 × 10.sup.−4 1.63 × 10.sup.−3 2.71 × 10.sup.−4 35 7.08 × 10.sup.−4 1.67 × 10.sup.−3 3.46 × 10.sup.−3 5.43 × 10.sup.−4 45 1.13 × 10.sup.−3 1.89 × 10.sup.−3 4.4 × 10.sup.−3 5.61 × 10.sup.−4 65 1.23 × 10.sup.−3 4.71 × 10.sup.−3 1.25 × 10.sup.−2 1.63 × 10.sup.−3 70 1.89 × 10.sup.−3 7.08 × 10.sup.−3 1.81 × 10.sup.−2 1.72 × 10.sup.−3
[0426] The temperature dependent conductivity of the polymer electrolytes increases with increases in temperature for all PEO/precursor compositions. The activation energy for these composite electrolytes decreases from 0.5 to 0.23 eV for Li.sub.2SiPHN vs. Li.sub.3PON precursor. This latter value might be ascribed to the amorphous nature of the polymer electrolyte with the addition of secondary PON phase, suppressing the crystallinity of the PEO and facilitating fast Li.sup.+ motion.
[0427] Symmetric Cell Studies
[0428] Symmetric Li/60 wt. % PEO+Li.sub.3PON and Li.sub.6SiPON/Li cells were assembled in a glovebox under Argon. Before cell assembly, Li metal was heated to 175° C. for 2 h, and 60 wt. % PEO+Li.sub.3PON and Li.sub.6SiPON polymer electrolyte were melt bonded onto the Li.
[0429]
[0430] CELGARD® separator coated with new batch Li.sub.3PON, Li.sub.6PON, Li.sub.2SiPHN, Li.sub.3SiPON and Li.sub.6SiPON.
[0431] CELGARD® separator Li-ion battery separator film (25 μm thick×18 mm diameter) substrates are dip-coated 1x in the precursor in Li.sub.3PON, Li.sub.6PON, Li.sub.2SiPHN, Li.sub.3SiPON, and Li.sub.6SiPON solutions using copper wire to suspend the sample. This experiment is conducted to measure the impedance of the polymer coatings without any heat treatments; which is similar to measuring the impedance of conventional liquid electrolyte.
[0432]
[0433]
[0434]
TABLE-US-00027 TABLE 27 List of equivalent series resistance of polymer-coated CELGARD ® separators at room temperature. Coated Resistance Celgard (Ω) Li.sub.3PON 350 Li.sub.6PON 50 Li.sub.2SiPHN 450 Li.sub.3SiPON 100 Li.sub.6SiPON 300
[0435] From these preliminary results, it can be concluded that the polymer precursors have optimal lithium ion diffusivity through the separator. Thus, they can be used to wet the cathode electrodes when all-solid state batteries are assembled. The wet conductivity results are Li.sub.2SiPHN<<Li.sub.3PON<<Li.sub.6SiPON<<Li.sub.3SiPON<Li.sub.6PON. The Li.sub.6PON precursor is a suitable electrolyte to be used when assembling a half-cell.
[0436] Li/Polymer Coated Separator/Li
[0437] A symmetric Li/CELGARD® separator+, Li.sub.3PON, Li.sub.6PON, Li.sub.3SiPON, and Li.sub.6SiPON/Li cells are assembled in a glovebox at UMEI under Argon flow. Before cell assembly, the metallic Li (16 mm diameter) is scraped to expose a clean surface. Symmetric cells are constructed using the standard procedure in a coin cell. The coin cells are compressed using a about 300 kPa uniaxial pressure. The symmetric cells are cycled at room temperature using a potentiostat/galvanostat (BioLogic SP300). The solution of polymer precursors dissolve in THF (20 μL) are used as an electrolyte.
[0438]
TABLE-US-00028 TABLE 28 List of charge transfer resistance (R.sub.ct), solid electrolyte interface resistance (R.sub.SEI), and for the symmetric cells using polymer-coated CELGARD ® separator films. Celgard + Polymer coating R.sub.ct Ω R.sub.SEI Ω Li.sub.3PON 4000 — Li.sub.6PON 500 3200 Li.sub.3SiPON 300 500 Li.sub.6SiPON 200 1400
[0439]
[0440]
[0441] The CELGARD® separator coated with Li.sub.6PON polymer precursors shows unstable voltage spikes when 0.1 mA current density is used. Higher current densities (0.1 mA) seem to result in higher interfacial impedance as presented by the increase in voltage response to 1V. However, the symmetric cell shows a stable voltage response (0.25 V) when the lower current density of 0.075 mA is used as shown in
[0442]
[0443]
[0444] Li.sub.2SiPHN
[0445] Li.sub.2SiPHN precursor is heated to 80° C./Vacuum. The resulting dried Li.sub.2SiPHN (1 g) powder is compacted into a pellet using 3 mm diameter die. The resulted pellets are heated between alumina plates to 100-600° C./2 h at a ramp rate of 1° C. min.sup.−1 under 120 ml min.sup.−1 N.sub.2 flow.
[0446]
[0447]
[0448] Table 29 illustrates the total ionic conductivities of a Li.sub.2SiPHN pellet heated to selected temperatures. Ionic conductivities of about 7×10.sup.−5S cm.sup.−1 are obtained when films are heated to 100° C.
TABLE-US-00029 TABLE 29 Total conductivities (σ.sub.t) of Li.sub.2SiPHN pellet heated to selected temperatures. T (° C.) σ(S cm.sup.−1) −15 6.22 × 10.sup.−7 0 8.3 × 10.sup.−7 25 1.24 × 10.sup.−6 45 2.45 × 10.sup.−5 65 1.75 × 10.sup.−5 85 3.56 × 10.sup.−5 100 7.0 × 10.sup.−5
[0449]
[0450]
[0451]
TABLE-US-00030 TABLE 30 Total conductivities (σ.sub.RT) of LiAlO.sub.2 + 300% films coated with polymers at selected temperatures. Film substrate Temp. (° C.) σ RT(S/cm) LiAlO.sub.2 + 100 1.4 ± 0.1 × 10.sup.−4 Li.sub.2SiPHN 200 7 ± 0.3 × 10.sup.−5 250 2.8 ± 0.3 × 10.sup.−5 300 3.1 ± 0.1 × 10.sup.−6
[0452] LIAlO.sub.2 substrates coated with Li.sub.2SiPHN do not show consistent conductivity when heat treated to 100-300° C. This can be ascribed to the fact that the coating is not stable in air and that the precursor suspension precipitates while coating. The conductivity drops in two orders of magnitude when treated from 100-300° C.
Example 16
[0453] Polymer precursor reactions for LiAlO.sub.x.
[0454] The first step is to develop a model system as illustrated immediately below.
##STR00013##
[0455] This reaction successfully produces an ethanol soluble aluminate. The use of excess LiO.sub.2CCH.sub.2CH.sub.3 can provide, on thermal decomposition, Li.sub.xAlO.sub.y where x>1. On solvent removal the aluminate complex is a crystalline solid that would be difficult to use for coatings unless it melts on heating.
[0456] Characterization Data
[0457] In a sample vial, 1 g of lithium propionate is added with 5.93 g of alumatrane (in EtOH), the ratio of Li:Al is 1:1 according to TGA results, about 10 mL more EtOH is added to the mixture. The reaction mixture is heated up to about 50° C. for 1 h while stirring magnetically. The solution becomes transparent.
[0458] Thereafter, the solvent is removed by rotatory evaporation, and the residue is vacuum dried in a vacuum oven at about 60° C. The yield is 3.0 g of yellow (or orange) solid.
[0459] TGA/DTA (1000° C./air) on the LiAlO.sub.x precursor shows a ceramic yield of 20.6% at 1000° C. The mass loss suggests that it decomposes around 350° C. leaving an intermediate char phase that oxidizes on heating from 430° C. to 580° C., slowly losing CO.sub.2 (or oxidation of residual carbon), then it decomposes again and remains stable from 630° C. The residue is an LiOAl compound (LiAlO.sub.2).
[0460]
Example 17
[0461] Lithium Aluminate from Polyacrylic Acid.
[0462] As an alternative to the LiO.sub.2CCH.sub.2CH.sub.3 component, it is also possible to make a polyacrylic acid (PAA) derivative as shown immediately below.
##STR00014##
[0463] The PAA derivative can then be reacted with alumatrane to produce a processable polymer precursor as shown immediately below.
##STR00015##
[0464] The ratio of Li to Al can be controlled by the stoichiometry of this reaction. Less alumatrane gives more Li in the Li.sub.xAlO.sub.y material to be produced.
[0465] Characterization Data
[0466] In a 100 ml round bottom flask, PAA (2.5 g, 1.25 mmol) and Li.sub.2CO.sub.3 (1.3 g, 17.3 mmol) are added with 30 mL of EtOH. The ratio of —CO.sub.2H group to Li.sub.2CO.sub.3 is 2:1. The reaction is kept stirring magnetically under N.sub.2 while heating at 60° C. with a reflux condenser.
[0467] The reaction mixture stays cloudy after 1 week of reacting, meaning that the reaction mixture is not very soluble in EtOH. Then 5 mL DI water is added to the reaction. A few minutes after adding the water, the solution clears up, but a white solid bulk forms, and it is floating on the surface of the solution. Gas also comes out from the reaction, which should be CO.sub.2. The reaction is kept running at 60° C. After 5 d of reacting with water, the white solid sinks down to the bottom, meaning no more CO.sub.2 is forming, the reaction is over. The solid is taken out from the reaction and a test on a small sample shows that it is water soluble.
[0468] The solid is then put into vacuum oven and dried at 60° C. for a few days. The yield of the product is 2.4 g after drying, and the theoretical yield is 2.7 g.
[0469]
Example 18
[0470] Synthesis of MgSiPON.
[0471] In a 50 ml round bottom Schlenk flask, NaNH.sub.2 (2.1 g, 0.06 mol) and OPCl.sub.3 (1.5 ml, 16.1 mmol) are added to 20 ml of distilled THF under N.sub.2 in an ice bath to form a reaction mixture. The reaction mixture becomes yellow about 5 min after reacting, showing that a reaction is taking place. The ice bath is removed after about 1 day of reacting.
[0472] After a week of reacting, soluble and insoluble parts in the reaction mixture are separated by centrifugation. The resulting liquid is an orange colored solution.
[0473] Thereafter, the solution is transferred into another 50 ml Schlenk flask. Mg(NSi.sub.2Me.sub.6).sub.2 (5.0 g, 14.5 mmol, about 90% equivalent amount of OPCl.sub.3) is added to the solution under N.sub.2 in an ice bath. No bubbles generated from the reaction mixture. The color of the reaction mixture turns dark after about 10 min of reacting. The reaction mixture remains a transparent solution, and no insoluble part forms. The ice bath is removed after 1 day of reacting.
[0474] MgSiPON Precursor.
[0475] A small sample of the liquid from the MgSiPON solution is taken and vacuum dried at 40° C. on a Schlenk line, then heated to 180° C. under vacuum for 1 h. The product is an orange solid. TGA and FTIR studies are run on the orange solid.
[0476] As shown in
[0477]
[0478] The residue is a dark solid. As shown in
Example 19
[0479] Precursors Used to Bond Different Components for Solid State Battery Assembly.
[0480] Because a precursor can be applied to multiple surfaces, it can be used to mate surfaces in its precursor form, such that on heating two mated surfaces, a ceramic ionic electrolyte bond is created.
[0481] Cathode+Precursor Electrolyte+Ceramic Electrolyte.
[0482] The precursor described here is Na.sub.3SiPON.
[0483] Na.sub.0.8CoO.sub.2 (NCO)+Na.sub.3SiPON+Na.sub.3.1Zr.sub.1.95Mg.sub.0.05Si.sub.2PO.sub.12 (NZMSP).
[0484]
[0485] Li.sub.4Ti.sub.5O.sub.12+Li.sub.3SiPON+LiAlO.sub.2+300%.
[0486] The interfacial behavior directly dictates the lifespan, energy density, and safety of all solid state batteries. These coatings might lower the interfacial resistance and stabilize the interfacial performance between SSE/electrode.
[0487] LiAlO.sub.2+300% green films are placed between α-alumina disks and heated at 665° C. for 2 h at a ramp rate of 3° C. min.sup.−1, followed by sintering to 1100° C./2 h at a ramp rate of 1° C. min.sup.−1 in air (100 ml min.sup.−1).
[0488] LiAlO.sub.2+300% films are dip-coated for 1 min in Li.sub.3SiPON solution and bonded to LTO films. The resulting anode-electrolyte are left to dry for 12 h under vacuum at 100° C. Dried samples are then heated up to 400° C./2 h/N.sub.2 at a ramp rate of 1° C./min.
[0489]
[0490] LTO+Li.sub.3SiPON+LATSP.
[0491] Green films of LATSP are placed in between alumina plates and debindered/crystallized at 665° C./2 h at a ramp rate of 5° C. min.sup.−1 followed by sintering at 1000° C./1 h at a ramp rate of 1° C. min.sup.−1 under 120 ml min.sup.−1 air flow.
[0492] LATSP films are dip-coated for 1 min in Li.sub.3SiPON solution and bonded to LTO films. The resulting anode-electrolyte are left to dry for 12 h under vacuum at 100° C. Dried samples are then heated up to 400° C./2 h/N.sub.2 at a ramp rate of 1° C./min.
[0493] Since LATSP is unstable against Li metal at high temperatures, an alternative anode material (LTO) is examined.
[0494]
Example 20
[0495] Precursor Used to Coat Particles of Cathode Materials.
[0496] LCO+LSP+Ag.
[0497] The main components of the electrodes are the active material and the electrolyte. When formulating composite cathodes, it is important that the content of the active material should be high as possible to increase the capacity. However, lowering the electrolyte content decreases the conduction path, and thus, decreases the utilization rate of the active materials, owing to limited charge transfer.
[0498] In order to optimize the electrode structure, a new composite cathode is formulated using commercial LiCoO.sub.2 powder, LSP nanopowder, Ag, and Li.sub.3PON and Li.sub.3SiPON precursor solutions.
[0499] Table 31 lists components used for making a suspension of LCO/LSP/Ag, with target volume fractions of 67/27/6 respectively. All the components are added to a 20 mL vial and ball-milled with 3.0 mm diameter ZrO.sub.2 beads (6 g) for 24 h to homogenize the suspension. The suspension is cast using a wire wound rod coater. Died green films are thermo-pressed at 50° C. with a pressure of 100 MPa for 5 min using a heated bench top press.
TABLE-US-00031 TABLE 31 Suspension formulation for (LCO/LSP/Ag). Role Mass (g) LCO Ceramic(cathode) 0.82 LSP Ceramic (electrolyte) 0.21 Ag Metal (current collector) 0.16 Polyvinyl Butyral Binder 0.11 Benzyl Butyl Phthalate Plasticizer 0.11 Ethanol Solvent 0.95 Acetone Solvent 0.95 Polyacrylic acid Dispersant 0.01 Li.sub.2B.sub.4O.sub.7 Ceramic(sintering-aid) 0.01
[0500] The resulting composite cathode is heated to 500° C./1 h/air for carbon burn out, then soaked for 1 min in Li.sub.3SiPON and Li.sub.3PON solution. The resulting composite cathode soaked in precursor electrolyte was left to dry for 12 h under vacuum at 100° C. Dried samples are then heated up to 400° C./2 h/N.sub.2 at a ramp rate of 1° C./min.
[0501]
Example 21
[0502] Coating of a Mg Conducting Ceramic with an Mg Electrolyte.
[0503] MZP:Fe+MgSiPON.
[0504] MZP:Fe green films are placed between α-alumina disks and sintered to 900° C. for 3 h at a ramp rate of 3° C. min.sup.−1 in air (100 ml min.sup.−1). MZP:Fe films are dip-coated for 1 min in MgSiPON solution. The resulting coated films are left to dry for 12 h under vacuum at 100° C. Dried samples are then heated up to 400° C./2 h/N.sub.2 at a ramp rate of 1° C./min.
[0505]
[0506] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.