SMALL FORM-FACTOR BATTERY WITH HIGH POWER DENSITY
20220216473 · 2022-07-07
Assignee
Inventors
- Mir A. Imran (Los Altos Hills, CA)
- Radia Abdul WAHAB (San Jose, CA, US)
- Chang Jin ONG (San Jose, CA, US)
Cpc classification
H01M50/609
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
H01M2004/021
ELECTRICITY
H01M50/186
ELECTRICITY
International classification
H01M4/62
ELECTRICITY
Abstract
A base cell structure includes a containment ring defining an opening extending therethrough. An inner wall of the containment ring defines a perimeter limit of a base cell volume. The containment ring provides a liquid-impermeable casing at the perimeter limit. A first set of active particles is disposed in the base cell volume of a first base cell structure to form an anode cell. A second set of active particles is disposed in the base cell volume of a second base cell structure to form a cathode cell. The anode cell and the cathode cell are assembled together with a separator disposed between. Two electrode plates are disposed on the assembly, one adjacent to the anode cell and one adjacent to the cathode cell, to respectively provide an anode electrode plate and a cathode electrode plate which are disposed on opposite outer sides of the assembly.
Claims
1. A small form factor battery, comprising: an anode cell comprising a first containment ring defining an opening therethrough and a wall of the first containment ring around the opening defining an anode cell volume, the first containment ring comprising a liquid-impermeable material; a cathode cell comprising a second containment ring defining an opening therethrough and a wall of the second containment ring around the opening defining a cathode cell volume, the second containment ring comprising a liquid-impermeable material; anode active particles disposed in the anode cell volume and having an average particle size of less than 1 μm; cathode active particles disposed in the cathode cell volume and having an average particle size of less than 1 μm; a separator disposed between the anode cell and the cathode cell; and two electrode plates, one disposed on the anode cell opposite the separator and one disposed on the cathode cell opposite the separator.
2. The battery of claim 1, wherein the anode active particles and the cathode active particles have an average particle size of less than 500 nm.
3. The battery of claim 2, wherein the anode active particles or the cathode active particles have an average particle size of less than 100 nm.
4. The battery of claim 2, wherein the anode active particles or the cathode active particles have an average particle size of less than 50 nm.
5. The battery of claim 2, wherein the anode active particles comprise silver oxide.
6. The battery of claim 2, wherein the cathode active particles comprise zinc.
7. The battery of claim 6, wherein the cathode active particles further comprise a polymeric binder.
8. The battery of claim 7, wherein the active particles contained within the cathode cell volume comprise 90%-99% zinc with the remainder being a polymeric binder.
9. The battery of claim 1, wherein the anode active particles or the cathode active particles are compacted and in a dry form.
10. The battery of claim 1, wherein a total particulate mass of the anode and cathode active particles is equal to or less than 4 mg, and the openings defined by the first and second containment rings each have a 3.81 mm diameter and about 101 μm height.
11. The battery of claim 1, further comprising one or more ports for adding electrolyte.
12. The battery of claim 1, further comprising an insulative encapsulating layer.
13. The battery of claim 1, wherein the cathode containment ring and/or the anode containment ring comprises a polymeric layer that provides a moisture barrier while being biochemically inert and chemically resistant.
14. The battery of claim 13, wherein the polymeric layer comprises poly-chloro-trifluoroethylene (PCTFE) film.
15. The battery of claim 1, wherein the form factor of the battery comprises an outer perimeter diameter of less than about 5.1 mm and a thickness of less than 381 μm.
16. A method of manufacturing a small form factor battery, comprising: providing a first ring-shaped laminate including a first containment ring having an inner perimeter and height together defining a first cell volume, and further including adhesive layers on opposing sides of the first containment ring; disposing a first electrode plate adjacent to the first ring-shaped laminate; filling first active particles into the first cell volume; providing a second ring-shaped laminate including a second containment ring having an inner perimeter and height together defining a second cell volume, the second containment ring having adhesive layers on opposing sides of the second containment ring; disposing a second electrode plate adjacent to the second ring-shaped laminate; filling second active particles into the second cell volume; and assembling the first ring-shaped laminate and the second ring-shaped laminate on opposing sides of a separator such that the first electrode plate and the second electrode plate are on opposing sides of the assembly.
17. The method of claim 16, wherein the first active particles and the second active particles have an average particle size of less than 500 nm.
18. The method of claim 16, wherein the first active particles or the second active particles have an average particle size of less than 100 nm.
19. The method of claim 16, wherein the first active particles or the second active particles have an average particle size of less than 50 nm.
20. The method of claim 16, wherein the first active particles volume comprises silver oxide.
21. The method of claim 16, wherein the second active particles comprise zinc.
22. The method of claim 21, wherein the second active particles further comprise a polymeric binder.
23. The method of claim 22, wherein the second active particles comprise 90%-99% zinc with the remainder being a polymeric binder.
24. The method of claim 16, further comprising compacting the first active particles and the second active particles in a dry form.
25. The method of claim 16, wherein a total particulate mass of the first and second active particles is equal to or less than 4 mg, and the first and second cell volumes are defined by a 3,81 mm diameter cell perimeter and 127 μm cell height.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
[0040] Before discussing details of the high capacity small form factor battery of the present disclosure, a few conventions are provided for the convenience of the reader.
[0041] Various abbreviations may be used herein for standard units, such as deciliter (dl), milliliter (ml), microliter (μl), international unit (IU), centimeter (cm), millimeter (mm), nanometer (nm), inch (in), kilogram (kg), gram (gm), milligram (mg), microgram (μg), millimole (mM), degrees Celsius (° C.), degrees Fahrenheit (° F.), millitorr (mTorr), hour (hr), or minute (min).
[0042] When used in the present disclosure, the terms “e.g.,” “such as”, “for example”, “for an example”, “for another example”, “examples of”, “by way of example”, and “etc.” indicate that a list of one or more non-limiting example(s) precedes or follows; it is to be understood that other examples not listed are also within the scope of the present disclosure.
[0043] As used herein, the singular terms “a,” “an,” and “the” may include plural referents unless the context clearly dictates otherwise. Reference to an object in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.”
[0044] The term “in an embodiment” or a variation thereof (e.g., “in another embodiment” or “in one embodiment”) refers herein to use in one or more embodiments, and in no case limits the scope of the present disclosure to only the embodiment as illustrated and/or described. Accordingly, a component illustrated and/or described herein with respect to an embodiment can be omitted or can be used in another embodiment (e.g., in another embodiment illustrated and described herein, or in another embodiment within the scope of the present disclosure and not illustrated and/or not described herein).
[0045] The term “component” refers herein to one item of a set of one or more items that together make up a device, formulation or system under discussion. A component may be in a solid, powder, gel, plasma, fluid, gas, or other form. For example, a device may include multiple solid components which are assembled together to structure the device and may further include a liquid component that is disposed in the device. For another example, a formulation may include two or more powdered and/or fluid components which are mixed together to make the formulation.
[0046] The term “design” or a grammatical variation thereof (e.g., “designing” or “designed”) refers herein to characteristics intentionally incorporated into a design based on, for example, estimates of tolerances related to the design (e.g., component tolerances and/or manufacturing tolerances) and estimates of environmental conditions expected to be encountered by the design (e.g., temperature, humidity, external or internal ambient pressure, external or internal mechanical pressure, external or internal mechanical pressure stress, age of product, or shelf life, or, if the design is introduced into a body, physiology, body chemistry, biological composition of fluids or tissue, chemical composition of fluids or tissue, pH, species, diet, health, gender, age, ancestry, disease, or tissue damage); it is to be understood that actual tolerances and environmental conditions before and/or after delivery can affect such designed characteristics so that different components, devices, formulations, or systems with a same design can have different actual values with respect to those designed characteristics. Design encompasses also variations or modifications to the design, and design modifications implemented after manufacture.
[0047] The term “manufacture” or a grammatical variation thereof (e.g., “manufacturing” or “manufactured”) as related to a component, device, formulation, or system refers herein to making or assembling the component, device, formulation, or system. Manufacture may be wholly or in part by hand and/or wholly or in part in an automated fashion.
[0048] The term “structured” or a grammatical variation thereof (e.g., “structure” or “structuring”) refers herein to a component, device, formulation, or system that is manufactured according to a concept or design or variations thereof or modifications thereto (whether such variations or modifications occur before, during, or after manufacture) whether or not such concept or design is captured in a writing.
[0049] The terms “substantially” and “about” are used herein to describe and account for small variations. For example, when used in conjunction with a numerical value, the terms can refer to a variation in the value of less than or equal to ±10%, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%.
[0050] As used herein, a range of numbers includes any number within the range, or any sub-range if the minimum and maximum numbers in the sub-range fall within the range. Thus, for example, “<9” can refer to any number less than nine, or any sub-range of numbers where the minimum of the sub-range is greater than or equal to zero and the maximum of the sub-range is less than nine. Ratios may also be presented herein in a range format. For example, a ratio in the range of about 1 to about 200 should be understood to include the explicitly recited limits of about 1 and about 200, and also to include individual ratios such as about 2, about 35, and about 74, and sub-ranges such as about 10 to about 50, about 20 to about 100, and so forth.
[0051] The discussion now continues with respect to high capacity small form factor batteries. Embodiments of the present description provide devices, systems, and methods of manufacture for a small form factor battery with high capacity per unit volume. The battery is implemented using nanopowders in dry form. The term nanopowder as used herein refers to a powdered material containing nanoparticles (e.g., amorphous or crystalline form) in nanometer scale.
[0052] The dry form nanopowder can be compacted into a desired shape prior to disposing the nanopowder in the battery, can be partially compacted prior to and partially compacted during or after disposing the nanopowder in the battery, or can be compacted during or after disposing the nanopowder in the battery.
[0053]
[0054] Battery 10 is preferably sized to have a compact form factor (e.g., a thickness of about 0.5 mm and diameter of about 5 mm for the embodiment illustrated in
[0055] The circular outer shape of battery 10 illustrated in
[0056] Referring to
[0057] In an embodiment, each base cell structure is provided as a ring-shaped laminate formed of an inner adhesive layer 18a and an outer adhesive layer 18b adhered on opposite sides of the containment ring 20, and the ring-shaped laminate defines the base cell volume in which active particles are disposed to form the anode cell or the cathode cell.
[0058] A separator 16 provides a barrier layer between the anode cell and the cathode cell. A first electrode plate 22 is positioned adjacent to the outer adhesive layer 18b of the anode cell and a second electrode plate 22 is positioned adjacent to the outer adhesive layer 18b of the cathode cell. An endplate 24 is positioned adjacent to each electrode plate 22.
[0059] In an embodiment, separator 16 includes porous material to allow passage of ions between the anode and cathode. In an embodiment, separator 16 includes porous material to allow passage of electrolyte between the anode and cathode. In an embodiment, separator 16 includes a hydrophilic material. In an embodiment, separator 16 includes a very thin film (e.g., 25.4 μm or 0.001 inch thick) including a hydrophilic, porous material. In an embodiment, separator 16 includes Cellophane P00 (from Futamura, USA Inc.). Separator 16 may include materials additional or alternative to those described above.
[0060] The active particles of the first or second base cell structures 12, 14 form an active component shape within battery 10 as manufactured (as indicated by respective disc shapes in the exploded view of
[0061] In general, capacity of a battery may be increased by increasing a surface area of the active component shape, such as by increasing cell volume; however, this would be counter-indicative for the goal of decreasing dimensions of a battery.
[0062] As provided for in the present disclosure, capacity of battery 10 can be increased without increasing cell volume. The active component shapes formed by active particles 12 or 14 as disposed in battery 10 are limited by the cell volume of the base cell structure used; however, as described in the present disclosure, a surface area to volume ratio of individual active particles of first and/or second base cell structures 12, 14 themselves can increase capacity of battery 10. Accordingly, active particles of first and second base cell structures 12, 14 are very fine particles, which provides for a significant increase in surface area that a respective electrolyte will contact. In an embodiment, active particles of first and second base cell structures 12, 14 are dry, compacted particles having average particulate sizes of less than 1 μm.
[0063] Active particles of first and second base cell structures 12, 14 may be compacted before and/or after being disposed in a base cell volume to obtain the respective anode cell or cathode cell.
[0064] In an embodiment, active particles of first base cell structure 12 of the anode include silver oxide (e.g., Ag(I)O) powder having an average particulate size of less than 500 nm. While 500 nm is presently the smallest average particle size that is generally commercially available for Ag(I)O, it is appreciated that alternative forms of Ag(I)O may become commercially available, or a process may be developed, to obtain Ag(I)O having an average particle size that is less than 500 nm, and even significantly less. In addition to or alternative to Ag(I)O, other anode materials may also be employed as appropriate, particularly those available in or processable to nanopowder particulate size. The smaller the particle size, the larger the surface area to volume ratio of each particle becomes, and the more particles may be disposed in a given volume. Accordingly, the use of nanoparticles provides for an increase in total contact surface area between the active component and the electrolyte, and thus the higher the capacity of the battery.
[0065] In an embodiment, active particles of second base cell structure 14 of the cathode include a zinc powder having an average particulate size of less than 100 nm. As with active particles of first base cell structure 12, smaller average particle size nanoparticles (e.g., less than 50 nm) may be employed when and where available.
[0066] In an embodiment, active particles of second base cell structure 14 of the cathode include a zinc powder mixed with a polymeric binder to help bind the zinc powder and aid in handling and compression of the powder. In an embodiment, a composition of active particles of second base cell structure 14 is 90%-99% zinc with the remainder being a polymeric binder. For example, in an embodiment, a composition of active particles of second base cell structure 14 is 95% zinc and 5% polymeric binder; in an embodiment, a composition of such active particles is 95% zinc and 5% polyethylene oxide (PEO). In an example of a method of manufacture, the PEO is added to and mixed with the zinc powder in dry form, and then pressure is applied to the mixture, generating a pressure-induced binding of the zinc powder and PEO powder. In addition to or alternative to zinc and PEO, other cathode materials may also be employed as appropriate, particularly those available in or processable to nanopowder particulate size.
[0067] The battery configuration and methods of manufacture disclosed herein, although suited for formation of many types of batteries and for the use of many types of active components, are particularly adapted to accommodating dry nanoparticles of less than 50 nm. For example, the methods of manufacture disclosed herein is particularly suited to compacting and confining nanoparticles in a dry form (e.g., not in a slurry or in the presence of liquid or electrolyte) to fill the anode cell and the cathode cell with densely packed nanoparticles.
[0068] The layered structure of battery 10 is configured to aid in the manufacturing process, and specifically with distribution and compaction of the nanopowders of the anode and cathode in the small confines of the form factor of battery 10.
[0069] In an embodiment, one or both containment rings 20 include a thin polymeric layer that provides a moisture barrier which is also biochemically inert and chemically resistant.
[0070] In an embodiment, one or both containment rings 20 include a poly-chloro-trifluoroethylene (PCTFE) film (e.g., such as manufactured under tradename ACLAR, by HONEYWLL INTERNATIONAL, INC.).
[0071] In an embodiment, the containment rings 20 each have a design height of 101 μm (or about 0.004 in) and the active particles 12 or 14 are shown extending approximately to a height of the respective containment rings 20. In other embodiments, the containment rings 20 have a height less than 101 μm or greater than 101 μm to accommodate a desired mass and density of active particles of first or second base cell structures 12, 14. In an embodiment, the containment ring 20 of the anode cell has a different height than the containment ring 20 of the cathode cell.
[0072] The cathode cell and the anode cell are defined by the containment rings 20 and also by the shared separator 16 on one (inner) side and a pair of electrode plates 22 on the opposing (outer) sides. In an embodiment, the separator 16 has a design thickness of 25.4 μm. In an embodiment, each electrode has a design thickness of 25.4 μm. Other thicknesses of separator 16 and electrode plates 22 are also envisioned.
[0073] In an embodiment, containment rings 20 have an annular shape as illustrated in
[0074] In an embodiment, at least one of the electrode plates includes nickel. Other metals or metal alloys or other conductive materials may be employed additionally or alternatively. In an embodiment, at least one of the electrode plates includes nickel coated on at least one side with silver.
[0075] In an embodiment, inner and outer adhesive layers 18a and 18b are positioned on opposing surfaces of containment rings 20. In the embodiment shown in
[0076] Adhesive layers 18a are configured to minimize movement of containment rings 20 against separator 16. Adhesive layers 18b are configured to minimize movement of containment rings 20 against electrode plates 22. In an embodiment, one or more sides of one or more of adhesive layers 18a and/or 18b have a high-friction surface to minimize movement. In an embodiment, one or more sides of one or more of adhesive layers 18a and/or 18b include an adhesive, which may include heat- or pressure-activated adhesive. In an embodiment, one or more sides of one or more of adhesive layers 18a and/or 18b include ethylene-vinyl acetate (EVA).
[0077] Battery 10 is capped with endplates 24, which may be electrically insulative and liquid-impermeable. In the configuration shown in the embodiment of
[0078]
[0079]
[0080] The cathode cell includes the second base structure 14, concentrically disposed with the containment ring 20. The cathode cell also includes outer adhesive layer 18b, disposed between the respective containment ring 20 and the separator 16. Additionally, the respective inner adhesive layer 18a is disposed between the containment ring 20 and the electrode 22 of the cathode cell. As described by some embodiments, the endplate 24 of the cathode cell can also include aperture 28 to provide electrical access to the respective electrode 22.
[0081] With reference to
[0082] As noted, particles may be compacted before or after being disposed in a base cell structure to form an anode cell or cathode cell. A layered structure such as battery 10 illustrated in
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[0097] For adhesive layers 18a, 18b which are heat-activated or pressure-activated, heat or pressure respectively may be employed at one or more stages of process 400 where desired, including at block 470.
[0098]
[0099] In an embodiment, electrolyte 99a and/or electrolyte 99b is introduced by injection. In an embodiment, the dry assembly of battery 10′ (block 470) is subjected to a vacuum and then immersed in electrolyte 99a or 99b as the vacuum is removed so that electrolyte 99a or 99b is drawn into the anode cell and/or cathode cell.
[0100] In embodiments in which adhesive layer 18a is or includes a hydrophilic material (e.g., adhesive layer 18a includes PVA), the hydrophilic material may promote ingress of electrolyte 99a and/or electrolyte 99b by a wicking action through the small confines of apertures 26.
[0101] Battery 10′ may optionally be stored in a dry state for a period of time without electrolyte 99a and/or without electrolyte 99b. Prior to use, the electrolyte is then introduced.
[0102]
[0103] As can be seen by process 400, generation of multiple (e.g., n=36, n=64, n=80, n=500, or more) separate components or multiple base cell structures may (but not necessarily) be formed concurrently.
[0104] Process 400 may be varied or modified. For example, apertures 26 may be generated in either of the adhesive layers 18a or 18b, the cathode cells or the anode cells may be generated sequentially or contemporaneously, or a base cell structure may be attached to the separator before being filled with active particles.
[0105]
[0106] In a bench test of another battery structured in accordance with the present description, the battery output was approximately 10 mA in a small form factor battery with diminutive outer dimensions of approximately 5.08 mm diameter and approximately 381 μm height (omitting end caps 22 and the encapsulant or housing).
[0107] An embodiment of a battery structured in accordance with the present description met the following requirements given for a specific application: voltage equal to or greater than 1.2 Volts, current equal to or greater than 10 mA with a 500 Ohm load, capacity of 0.5 mA-h or greater, and a form factor with less than 5.08 mm diameter and less than 381 μm height.
[0108] The foregoing description of various embodiments of the invention has been presented for purposes of illustration and description. It is not intended to limit the invention to the precise forms disclosed. Many modifications, variations and refinements will be apparent to practitioners skilled in the art. For example, embodiments of the device can be sized and otherwise adapted for various applications. Also, those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific devices and methods described herein. Such equivalents are considered to be within the scope of the present invention and are covered by the appended claims below.
[0109] Elements, characteristics, or acts from one embodiment can be readily recombined or substituted with one or more elements, characteristics or acts from other embodiments to form numerous additional embodiments within the scope of the invention. Moreover, elements that are shown or described as being combined with other elements, can, in various embodiments, exist as standalone elements. Hence, the scope of the present invention is not limited to the specifics of the described embodiments, but is instead limited solely by the appended claims.