Lithium orthophosphate glasses, corresponding glass-ceramics and lithium ion-conducting NZP glass ceramics

Abstract

A lithium-ion conductive glass-ceramic article has a crystalline component characterized by the formula MA.sub.2(XO.sub.4).sub.3, where M represents one or more monovalent or divalent cations selected from Li, Na and Zn, A represents one or more trivalent, tetravalent or pentavalent cations selected from Al, Cr, Fe, Ga, Si, Ti, Ge, V and Nb, and X represents P cations which may be partially substituted by B cations.

Claims

1. A glass-ceramic having a composition comprising, in mole percent: 5-28% Li.sub.2O, 14-37% TiO.sub.2, and 32-48% P.sub.2O.sub.5, and further comprising at least one relationship (i)-(iii), wherein (i) the composition comprises at least two oxides selected from the group consisting of >0-13% Al.sub.2O.sub.3, >0-13% Fe.sub.2O.sub.3 and >0-13% Nb.sub.2O.sub.5; (ii) the composition comprises at least two oxides selected from the group consisting of >0-10% Cr.sub.2O.sub.3, >0-5% SiO.sub.2 and >0-25% GeO.sub.2; and (iii) the composition comprises at least three oxides selected from the group consisting of >0-13% Al.sub.2O.sub.3, >0-13% Fe.sub.2O.sub.3; >0-13% Nb.sub.2O.sub.5, >0-10% Cr.sub.2O.sub.3, >0-5% SiO.sub.2 and >0-25% GeO.sub.2; and wherein the glass-ceramic comprises at least 70 vol % of a NZP crystalline phase and a lithium ion conductivity of at least 110.sup.4 S/cm.

2. The glass-ceramic according to claim 1, comprising 4-10% Al.sub.2O.sub.3 and 4-10% Nb.sub.2O.sub.5.

3. The glass-ceramic according to claim 1, further comprising 1-4% B.sub.2O.sub.3.

4. The glass-ceramic according to claim 1, comprising 4-10% Al.sub.2O.sub.3, 4-10% Nb.sub.2O.sub.5 and 1-4% B.sub.2O.sub.3.

5. The glass-ceramic according to claim 1, comprising 1-8% Cr.sub.2O.sub.3 and 4-20% GeO.sub.2.

6. The glass-ceramic according to claim 1, further comprising at least one oxide selected from the group consisting of >0-17% Na.sub.2O and >0-17% ZnO.

7. A glass-ceramic article having a NZP crystalline phase characterized by the formula M.sub.yA.sub.2(XO.sub.4).sub.3, (0.1y2.2) where M represents one or more monovalent or divalent cations selected from the group consisting of Li, Na and Zn, A represents one or more trivalent, tetravalent or pentavalent cations selected from the group consisting of Al, Cr, Fe, Ga, Si, Ti, Ge, V and Nb, and X represents P cations which may be partially substituted by B cations, and further comprising at least one relationship (i)-(iii), wherein (i) A represents two or more cations selected from the group consisting of Al, Fe and Nb; and (ii) A represents two or more cations selected from the group consisting of Cr, Si and Ge; and (iii) A represents three or more cations selected from the group consisting of Al, Fe, Nb, Cr, Si and Ge; and wherein the glass-ceramic article comprises at least 70 vol % of the NZP crystalline phase and a lithium ion conductivity of at least 110.sup.4 S/cm.

8. The glass-ceramic article according to claim 7, wherein M represents Li and Zn.

9. The glass-ceramic article according to claim 7, wherein A represents Al, Ti and Nb.

10. The glass-ceramic article according to claim 7, wherein A represents Cr, Ti and Ge.

11. The glass-ceramic article according to claim 7, wherein A represents three or more cations selected from the group consisting of Al, Cr, Fe, Ga, Si, Ti, Ge, V and Nb.

12. The glass-ceramic article according to claim 7, wherein X represents P and B.

13. The glass-ceramic article according to claim 7, comprising 4-10 mol. % Al.sub.2O.sub.3 and 4-10 mol. % Nb.sub.2O.sub.5.

14. The glass-ceramic article according to claim 7, comprising 1-4 mol. % B.sub.2O.sub.3.

15. The glass-ceramic article according to claim 7, comprising 4-10 mol. % Al.sub.2O.sub.3, 4-10 mol. % Nb.sub.2O.sub.5 and 1-4 mol. % B.sub.2O.sub.3.

16. The glass-ceramic article according to claim 7, comprising 1-8 mol. % Cr.sub.2O.sub.3 and 4-20 mol. % GeO.sub.2.

17. The glass-ceramic article according to claim 7, wherein the glass-ceramic article comprises less than 1 vol % of glassy phase.

18. The glass-ceramic article according to claim 7, wherein the article has a thickness of less than 2 mm.

19. The glass-ceramic article according to claim 7, wherein M is Li and 1.2y2.2.

20. A glass-ceramic comprising at least 70 vol % of a NZP crystalline phase and having a composition comprising, in mole percent: 5-28% Li.sub.2O, 14-37% TiO.sub.2, 32-48% P.sub.2O.sub.5, and at least one oxide selected from the group consisting of >0-17% Na.sub.2O and >0-17% ZnO, and further comprising at least one relationship (i)-(iv), wherein (i) the composition comprises at least two oxides selected from the group consisting of >0-13% Al.sub.2O.sub.3, >0-13% Fe.sub.2O.sub.3 and >0-13% Nb.sub.2O.sub.5; (ii) the composition comprises at least two oxides selected from the group consisting of >0-10% Cr.sub.2O.sub.3, >0-5% SiO.sub.2 and >0-25% GeO.sub.2; (iii) the composition comprises at least three oxides selected from the group consisting of >0-13% Al.sub.2O.sub.3, >0-13% Fe.sub.2O.sub.3; >0-13% Nb.sub.2O.sub.5, >0-10% Cr.sub.2O.sub.3 and >0-25% GeO.sub.2; and (iv) the composition comprises at least three oxides selected from the group consisting of >0-13% Fe.sub.2O.sub.3; >0-13% Nb.sub.2O.sub.5, >0-10% Cr.sub.2O.sub.3, >0-5% SiO.sub.2 and >0-25% GeO.sub.2.

21. The glass-ceramic according to claim 20, wherein the glass-ceramic comprises less than 5 vol % of glassy phase.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The following detailed description of specific embodiments of the present disclosure can be best understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:

(2) FIG. 1 is a compositional landscape for Ti, Cr and Ge-containing materials showing glass forming regions and ionic conductivities;

(3) FIG. 2 is a DSC scan for a glass composition according to one embodiment;

(4) FIG. 3 is a DSC scan for a glass composition according to a further embodiment;

(5) FIG. 4 is an XRD scan for a glass-ceramic according to one embodiment;

(6) FIG. 5 is an SEM micrograph of the glass-ceramic of FIG. 4;

(7) FIG. 6 is a DSC scan for a glass composition according to a further embodiment;

(8) FIG. 7 is an XRD scan for a glass-ceramic according to one embodiment; and

(9) FIG. 8 is a plot of weight loss versus time for example glass-ceramic compositions when submerged in deionized water.

DETAILED DESCRIPTION

(10) Reference will now be made in greater detail to various embodiments of the subject matter of the present disclosure, some embodiments of which are illustrated in the accompanying drawings. The same reference numerals will be used throughout the drawings to refer to the same or similar parts.

(11) Disclosed are precursor glasses and NASICON-type (i.e., NZP-type) materials that are formed via a glass-ceramic route. According to various embodiments, vitreous domains in Li.sub.2OTiO.sub.2P.sub.2O.sub.5 are disclosed, further comprising one or more of Al.sub.2O.sub.3, Cr.sub.2O.sub.3, Fe.sub.2O.sub.3, Ga.sub.2O.sub.3, SiO.sub.2, GeO.sub.2, V.sub.2O.sub.5, Nb.sub.2O.sub.5, Na.sub.2O, ZnO and B.sub.2O.sub.3.

(12) The glasses are obtained by melting of a mixture of Li.sub.2CO.sub.3(s) and/or LiH.sub.2PO.sub.4(s), TiO.sub.2(s), H.sub.3PO.sub.4(aq) and an oxide, carbonate or phosphate of one or more additional metal(s). The dry batch ingredients can be turbula milled, for example, prior to the addition of aqueous phosphoric acid to form a slurry. The slurry is calcined.

(13) The calcination time and temperature may range from 1-12 h and 300-500 C., respectively. An example calcination time is 6 h and an example calcination temperature is 400 C. Following calcination, the batch is placed in a melting furnace. Calcined batches are melted at 1400-1600 C. (e.g., 1500 C.) and then roller quenched to form thin sheets. Molten material can be quenched from the melt temperature to less than 600 C. at a quench rate of from 40 C./min to 200 C./min (e.g., 80 or 100 C./min). The molten material can be roller quenched on a stainless steel substrate.

(14) The glass sheets may have areal dimensions of several square centimeters, though the process may be scaled to larger area sheets. The melt can be quenched and rolled into sheets having a maximum thickness of 2 mm. In embodiments, the thickness of the glass sheets was about 0.5 to 1 mm.

(15) The roller-quenched glass is then heat treated to nucleate and grow the crystalline phase. The heat treatment can be performed under ambient conditions. A heating rate to a nucleation temperature can range from 1 C./min to 20 C./min, e.g., 1, 2, 5, 10 or 20 C./min. A heating rate to a crystal growth temperature can range from 1 C./min to 20 C./min, e.g., 1, 2, 5, 10 or 20 C./min. Depending on the composition of the batch, the nucleation temperature can range from 500 C. to 700 C. and the crystal growth temperature can range from 800 C. to 900 C. A nucleation time and a crystal growth time can range from 0 to 2 h and 0.25 h to 72 h, respectively.

(16) When the glass is subjected to a heat treatment above its crystallization temperature (T.sub.x), the dominant phase of the resultant glass-ceramic has the rhombohedral NZP structure. In embodiments, the crystal growth temperature is at least 50 C. greater, e.g., at least 100 C., 200 C., 300 C. or 350 C. greater than the crystallization temperature (T.sub.x) of the composition.

(17) In the NASICON framework, represented by the formula M(1)M(2)A.sub.2(XO.sub.4).sub.3, the crystal structure comprises a three-dimensional network of XO.sub.4 tetrahedra sharing corners with AO.sub.6 octahedra. The M(1) sites are surrounded by six oxygen atoms and located at an inversion center. The M(2) sites are symmetrically-distributed around a three-fold axis with ten-fold oxygen coordination.

(18) Without wishing to be bound by theory, the M(1) and M(2) sites are principally occupied by one or more alkali metal ions such as Li or Na, though the alkali metal ions may be substituted partly by Zn or a vacancy. The symbol A represents two or more (e.g., three or more) multivalent metal ions, e.g., Al, Cr, Fe, Ga, Si, Ti, Ge, V and Nb, and the symbol X is principally phosphorus (P) though the phosphorus may be substituted partially by B.

(19) The resulting glass-ceramic membrane can have an average thickness of less than 2 mm, e.g., from 0.5 to 1 mm. In embodiments, the glass-ceramic can have an average thickness of less than 200 microns, where the constituent crystalline material can have an average grain size of less than 10 um, e.g., less than 1 um. Self-supporting glass-ceramic membranes as thin as 100 microns can be formed.

(20) The glass-ceramic article may contain less than 5 vol. % retained glassy phase. In embodiments, the glass-ceramic article is entirely crystalline or contains at most 1 vol. % or 2 vol. % retained glass. In further embodiments, the glass-ceramic includes a NZP-type crystal as the majority crystalline phase. By majority crystalline phase, it is meant that the glass-ceramic can include at least 70 vol. % (e.g., at least 70, 75, 80, 85, 90 or 95 vol. %) NZP phase. The glass-ceramic may contain an NZP-type crystalline phase as the sole crystal phase.

(21) The composition of the batch of raw materials can correspond directly to the stoichiometry of the crystal phase that is desired. Thus the disclosed glass compositions and the disclosed glass-ceramic compositions may each include, in mol. %: 5-28% Li.sub.2O, 14-37% TiO.sub.2, and 32-48% P.sub.2O.sub.5 with one or more of the following: 0-13% Al.sub.2O.sub.3, 0-10% Cr.sub.2O.sub.3, 0-13% Fe.sub.2O.sub.3, 0-10% Ga.sub.2O.sub.3, 0-5% SiO.sub.2, 0-25% GeO.sub.2, 0-7% V.sub.2O.sub.5, 0-13% Nb.sub.2O.sub.5, 0-17% Na.sub.2O, 0-17% ZnO and 0-6% B.sub.2O.sub.3.

(22) The glass compositions, in example embodiments, comprise 5-28% Li.sub.2O, 14-37% TiO.sub.2, and 32-48% P.sub.2O.sub.5, and further comprising at least one relationship (i)-(iii), wherein (i) the composition comprises at least two oxides selected from the group consisting of >0-13% Al.sub.2O.sub.3, >0-13% Fe.sub.2O.sub.3 and >0-13% Nb.sub.2O.sub.5, (ii) the composition comprises at least two oxides selected from the group consisting of >0-10% Cr.sub.2O.sub.3, >0-5% SiO.sub.2 and >0-25% GeO.sub.2; and (iii) the composition comprises at least three oxides selected from the group consisting of >0-13% Al.sub.2O.sub.3, >0-13% Fe.sub.2O.sub.3; >0-13% Nb.sub.2O.sub.5, >0-10% Cr.sub.2O.sub.3, >0-5% SiO.sub.2 and >0-25% GeO.sub.2.

(23) The composition of the glass may correspond stoichiometrically to the NZP crystal phase. In related embodiments, the composition of the glass may be non-stoichiometric with respect to the NZP crystal phase. For example, the glass composition may be up to 10 mol. % deficient or may contain up to 10 mol. % excess of one or more constituents. A glass may be prepared, for instance, with 5% or even 10% excess phosphorus.

(24) The resulting glass-ceramic has a crystalline component characterized by the formula M.sub.yA.sub.2(XO.sub.4).sub.3 (0.1y2.2), where M represents one or more monovalent or divalent cations selected from the group consisting of Li, Na and Zn, A represents two or more trivalent, tetravalent or pentavalent cations selected from the group consisting of Al, Cr, Fe, Ga, Si, Ti, Ge, V and Nb, and X represents P cations which may be partially substituted by B cations, and further comprising at least one relationship (i)-(iii), where (i) A represents two or more cations selected from the group consisting of Al, Fe and Nb; (ii) A represents two or more cations selected from the group consisting of Cr, Si and Ge; and (iii) A represents three or more cations selected from the group consisting of Al, Fe, Nb, Cr, Si and Ge. In example glass-ceramic compositions, M is Li and the subscript y can range from 1.2 to 2.2.

(25) In embodiments, A may represent two or more trivalent, tetravalent or pentavalent cations selected from the group consisting of Al, Cr, Fe, Ga, Si, Ti, Ge, V and Nb. In further embodiments, A may represent three or more trivalent, tetravalent or pentavalent cations selected from the group consisting of Al, Cr, Fe, Ga, Si, Ti, Ge, V and Nb. In still further embodiments, A may represent four or more trivalent, tetravalent or pentavalent cations selected from the group consisting of Al, Cr, Fe, Ga, Si, Ti, Ge, V and Nb.

(26) It will be appreciated that in the idealized stoichiometry, M.sub.yA.sub.2(XO.sub.4).sub.3 (0.1y2.2), the elemental constituents may be located on alternate sites to those described above. For example, in a Li.sub.1.3Nb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 glass ceramic, the aluminum (Al) may be located on an X site or on an interstitial site within the crystalline matrix.

(27) Example glass stoichiometries are summarized in Table 1, where the constituent compositions are given in molar %.

(28) The Li.sub.2O content (in mol. %) of the disclosed glass and glass-ceramic compositions can range from 5-28%. For example, the compositions may include from 10-22% or from 12-20% Li.sub.2O, e.g., 10, 12, 14, 16, 18, 20 or 22% Li.sub.2O. The amount of TiO.sub.2 (in mol. %) of the disclosed glass and glass-ceramic compositions can range from 14-37%. In embodiments, the composition include at least 18 mol. % TiO.sub.2. For example, the compositions may include from 18-36% or from 20-30% TiO.sub.2, e.g., 20, 22, 24, 26, 28 or 30% TiO.sub.2. The amount of P.sub.2O.sub.5 (in mol. %) of the disclosed glass and glass-ceramic compositions can range from 32-48%. For example, the compositions may include from 36-46% or from 38-42% P.sub.2O.sub.5, e.g., 36, 38, 40, 42, 44 or 46% P.sub.2O.sub.5.

(29) The disclosed glass and glass-ceramic compositions may optionally include Al.sub.2O.sub.3 or Fe.sub.2O.sub.3. The Al.sub.2O.sub.3 or Fe.sub.2O.sub.3 content (in mol. %) can independently range from 0-13%. For example, the compositions may include from 4-10% or from 6-8% Al.sub.2O.sub.3, e.g., 4, 6 or 8% Al.sub.2O.sub.3. The compositions may include from 2-12%, 2-6% or from 4-10% Fe.sub.2O.sub.3, e.g., 2, 4, 6, 8 or 10% Fe.sub.2O.sub.3.

(30) The disclosed glass and glass-ceramic compositions may optionally include Cr.sub.2O.sub.3 or Ga.sub.2O.sub.3. The Cr.sub.2O.sub.3 or Ga.sub.2O.sub.3 content (in mol. %) can independently range from 0-10%. For example, the Cr.sub.2O.sub.3 may range from 1-8% or from 4-6%, e.g., 1, 2, 4, 6, or 8% Cr.sub.2O.sub.3. The Ga.sub.2O.sub.3 content may range from 4-8% or from 6-8%, for example.

(31) The disclosed compositions may optionally include from 0-5 mol. % SiO.sub.2, e.g., from 2-4 mol. % SiO.sub.2.

(32) The disclosed compositions may optionally include from 0-25 mol. % GeO.sub.2. For example, the compositions may include from 4-20%, 6-10% or from 10-15% GeO.sub.2, e.g., 4, 6, 8, 10, 12, 14 or 16% GeO.sub.2.

(33) The disclosed compositions may optionally include from 0-7 mol. % V.sub.2O.sub.5, e.g., from 2-6% or from 4-6% V.sub.2O.sub.5.

(34) The disclosed compositions may optionally include from 0-13 mol. % Nb.sub.2O.sub.5. For example, the compositions may include from 4-10% or from 4-8% Nb.sub.2O.sub.5, e.g., 4, 6, 8 or 10% Nb.sub.2O.sub.5.

(35) The disclosed compositions may optionally include Na.sub.2O or ZnO. The Na.sub.2O or ZnO content (in mol. %) can independently range from 0-17%. The compositions may include, for example, 4-10% or 6-8% ZnO, e.g., 4, 6, 8 or 10% ZnO.

(36) The disclosed compositions may optionally include from 0-6 mol. % B.sub.2O.sub.3, e.g., 1-6% or 1-4% B.sub.2O.sub.3.

(37) TABLE-US-00001 TABLE 1 Stoichiometry and composition of example lithium ion-conducting materials. Stoichiometry Li.sub.2O TiO.sub.2 P.sub.2O.sub.5 ZnO Al.sub.2O.sub.3 Cr.sub.2O.sub.3 Fe.sub.2O.sub.3 SiO.sub.2 GeO.sub.2 V.sub.2O.sub.5 Nb.sub.2O.sub.5 B.sub.2O.sub.3 Zn.sub.0.25Li.sub.0.5Fe.sub.0.7Nb.sub.0.7Ti.sub.0.6(PO.sub.4).sub.3 7.58 18.18 45.45 7.58 10.61 10.61 LiFe.sub.0.7Nb.sub.0.7Ti.sub.0.6(PO.sub.4).sub.3 15.15 18.18 45.45 10.61 10.61 Zn.sub.0.15LiFe.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 13.51 29.73 40.54 4.05 4.05 4.05 4.05 Zn.sub.0.25Li.sub.0.8Fe.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 10.81 29.73 40.54 6.76 4.05 4.05 4.05 Li.sub.1.3Nb.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 17.57 29.73 40.54 8.11 4.05 Zn.sub.0.15LiNb.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 13.51 29.73 40.54 4.05 8.11 4.05 Zn.sub.0.25Li.sub.0.8Nb.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 10.81 29.73 40.54 6.76 8.11 4.05 Zn.sub.0.4LiAl.sub.0.8Ti.sub.1.2(PO.sub.4).sub.3 12.82 28.21 38.46 10.26 10.26 Zn.sub.0.3LiCr.sub.0.3Al.sub.0.3Ti.sub.1.4(PO.sub.4).sub.3 13.51 29.73 40.54 8.11 4.05 4.05 Li.sub.1.6Ga.sub.0.6Ti.sub.1.4(PO.sub.4).sub.3 20.00 35.00 37.50 Zn.sub.0.3Li.sub.1.3Fe.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 16.25 27.50 37.50 7.50 7.50 3.75 Li.sub.1.3Cr.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 17.57 29.73 40.54 4.05 4.05 4.05 LiNb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.3 14.08 30.99 42.25 6.34 6.34 Li.sub.0.95Nb.sub.0.4Al.sub.0.35Ti.sub.1.25(PO.sub.4).sub.3 13.19 34.72 41.67 4.86 5.56 LiNb.sub.0.6Al.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3 14.71 23.53 44.12 8.82 8.82 Li.sub.1.6Fe.sub.0.3Nb.sub.0.3Al.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3 21.62 21.62 40.54 8.11 4.05 4.05 Li.sub.1.3V.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 17.57 29.73 40.54 8.11 4.05 Li.sub.0.7V.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 10.29 32.35 44.12 4.41 4.41 4.41 Li.sub.1.3Nb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 (example 1) 17.57 29.73 38.51 6.08 6.08 2.03 Li.sub.1.6Nb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.2.7(BO.sub.4).sub.0.3 20.78 28.57 35.06 5.84 5.84 3.90 Li.sub.1.3Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 (example 2) 16.25 27.50 37.50 3.75 15.00 Li.sub.1.3Cr.sub.0.3Ge.sub.0.9Ti.sub.0.8(PO.sub.4).sub.3 16.25 20.00 37.50 3.75 22.50 Li.sub.1.4Fe.sub.0.3Nb.sub.0.3Al.sub.0.4Ti.sub.1.0(PO.sub.4).sub.3 18.92 27.03 40.54 5.41 4.05 4.05 Li.sub.1.4Fe.sub.0.4Nb.sub.0.4Al.sub.0.4Ti.sub.0.8(PO.sub.4).sub.3 19.44 22.22 41.67 5.56 5.56 5.56 Li.sub.1.6Cr.sub.0.6Ge.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3 (example 3) 20.00 20.00 37.50 7.50 15.00 Li.sub.1.6Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 (example 4) 19.28 26.51 34.34 3.61 14.46 1.81 Li.sub.1.4Cr.sub.0.4Ge.sub.0.4Ti.sub.1.2(PO.sub.4).sub.3 17.50 30.00 37.50 5.00 10.00 Li.sub.1.6Cr.sub.0.3Al.sub.0.3Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 20.00 27.50 37.50 3.75 3.75 7.50 LiNb.sub.0.45Al.sub.0.45Ge.sub.0.2Ti.sub.0.9(PO.sub.4).sub.3 14.08 25.35 42.25 6.34 5.63 6.34 Li.sub.1.9Cr.sub.0.6Ge.sub.0.6Ti.sub.0.8(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 22.89 19.28 34.34 7.23 14.46 1.81 Li.sub.1.6Cr.sub.0.6Si.sub.0.1Ti.sub.1.3(PO.sub.4).sub.3 20.00 32.50 37.50 7.50 2.50 Li.sub.1.9Cr.sub.0.6Si.sub.0.1Ti.sub.1.3(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 22.89 31.33 34.34 7.23 2.41 1.81 Li.sub.1.9Cr.sub.0.3Al.sub.0.3Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 22.89 26.51 34.34 3.61 3.61 7.23 1.81 Li.sub.1.8Cr.sub.0.4Al.sub.0.4Ge.sub.0.3Ti.sub.0.9(PO.sub.4).sub.3 22.50 22.50 37.50 5.00 5.00 7.50 Li.sub.2.1Cr.sub.0.4Al.sub.0.4Ge.sub.0.3Ti.sub.0.9(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 25.30 21.69 34.34 4.82 4.82 7.23 1.81 Li.sub.1.6Cr.sub.0.6Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 20.00 27.50 37.50 7.50 7.50 Li.sub.1.9Cr.sub.0.6Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 22.89 26.51 34.34 7.23 7.23 1.81 Li.sub.1.3Nb.sub.0.45Al.sub.0.45Ge.sub.0.2Ti.sub.0.9(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 17.57 24.32 38.51 6.08 5.41 6.08 2.03 LiNb.sub.0.3Al.sub.0.3Ge.sub.0.2Ti.sub.1.2(PO.sub.4).sub.3 13.51 32.43 40.54 4.05 5.41 4.05 Li.sub.1.3Fe.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 17.57 29.73 38.51 4.05 4.05 4.05 2.03 Li.sub.1.6Cr.sub.0.3Si.sub.0.6Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 19.28 26.51 34.34 3.61 14.46 1.81 Li.sub.1.1Cr.sub.0.1Ge.sub.0.8Ti.sub.1.1(PO.sub.4).sub.3 13.75 27.50 37.50 1.25 20.00 Li.sub.1.2Cr.sub.0.2Ge.sub.0.7Ti.sub.1.1(PO.sub.4).sub.3 15.00 27.50 37.50 2.50 17.50 Li.sub.1.4Cr.sub.0.4Ge.sub.0.5Ti.sub.1.1(PO.sub.4).sub.3 17.50 27.50 37.50 5.00 12.50 Li.sub.1.5Cr.sub.0.5Ge.sub.0.4Ti.sub.1.1(PO.sub.4).sub.3 18.75 27.50 37.50 6.25 10.00 Li.sub.1.7Cr.sub.0.7Ge.sub.0.2Ti.sub.1.1(PO.sub.4).sub.3 21.25 27.50 37.50 8.75 5.00 Li.sub.1.7Cr.sub.0.7Ge.sub.0.7Ti.sub.0.6(PO.sub.4).sub.3 21.25 15.00 37.50 8.75 17.50 Li.sub.1.45Cr.sub.0.45Ge.sub.0.45Ti.sub.1.1(PO.sub.4).sub.3 (example 5) 18.13 27.50 37.50 5.63 11.25 Li.sub.1.3Cr.sub.0.3Ge.sub.0.5Ti.sub.1.2(PO.sub.4).sub.3 16.25 30.00 37.50 3.75 12.50 Li.sub.1.6Cr.sub.0.6Ge.sub.0.4Ti.sub.1.0(PO.sub.4).sub.3 20.00 25.00 37.50 7.50 10.00 Li.sub.1.7Cr.sub.0.7Ge.sub.0.4Ti.sub.0.9(PO.sub.4).sub.3 21.25 22.50 37.50 8.75 10.00 Li.sub.1.8Cr.sub.0.8Ge.sub.0.4Ti.sub.0.8(PO.sub.4).sub.3 22.50 20.00 37.50 10.00 10.00 Li.sub.1.5Cr.sub.0.5Ge.sub.0.3Ti.sub.1.2(PO.sub.4).sub.3 18.75 30.00 37.50 6.25 7.50 Li.sub.1.5Cr.sub.0.5Ge.sub.0.5Ti.sub.1.0(PO.sub.4).sub.3 18.75 25.00 37.50 6.25 12.50 Li.sub.1.5Cr.sub.0.5Ge.sub.0.7Ti.sub.0.8(PO.sub.4).sub.3 18.75 20.00 37.50 6.25 17.50 Li.sub.1.5Cr.sub.0.5Ge.sub.0.8Ti.sub.0.7(PO.sub.4).sub.3 18.75 17.50 37.50 6.25 20.00 Li.sub.1.55Cr.sub.0.55Ge.sub.0.35Ti.sub.1.1(PO.sub.4).sub.3 19.38 27.50 37.50 6.88 8.75

(38) Compositions within the system CrGeTi, for example, i.e., lithium-chromium-germanium-titanium phosphates, display good glass formability (i.e., a glass formability index in the range of 4-5) within the region 1-10 mol % Cr.sub.2O.sub.3, 5-25 mol % GeO.sub.2, and 15-30 mol % TiO.sub.2 (see FIG. 1). Conductivities of at least 10.sup.4 S/cm are observed for compositions within the region 5-7 mol % Cr.sub.2O.sub.3, 8.5-20 mol % GeO.sub.2 and 17-28 mol % TiO.sub.2.

(39) A method of making a glass-ceramic article comprises forming a glass melt including, in mole percent, 5-28% Li.sub.2O, 14-37% TiO.sub.2, 32-48% P.sub.2O.sub.5, 0-13 Al.sub.2O.sub.3, 0-10 Cr.sub.2O.sub.3, 0-13 Fe.sub.2O.sub.3, 0-10 Ga.sub.2O.sub.3, 0-5% SiO.sub.2, 0-25 GeO.sub.2, 0-7 V.sub.2O.sub.5, 0-13 Nb.sub.2O.sub.5, 0-17 Na.sub.2O, 0-17 ZnO and 0-6 B.sub.2O.sub.3, quenching the melt to form a glass article, and heat treating the glass article to form a glass-ceramic article having an NZP phase as a majority crystalline phase.

(40) As compared with traditional ceramic routes, i.e., powder sintering, the glass-ceramic materials made by the instant approach are fully dense. Further, the glasses can be made directly to the desired shape by casting and then then, via heat treatment, crystallized into a dense NZP glass-ceramic. Some NZP glass-ceramics are characterized by high ionic conductivity. The disclosed glass-ceramic route is more cost and time effective than traditional ceramic processing.

EXAMPLES

Example 1Li1.3Nb0.45Al0.45Ti1.1(PO4)2.85(BO4)0.15

(41) Dry powders of lithium carbonate, niobium pentoxide, aluminum metaphosphate, titanium dioxide, and boric acid were mixed in a turbula mixer. The powder mix was poured into a Pt crucible and an aqueous solution of phosphoric acid was added to the dry mix and stirred to form a homogeneous slurry. The slurry was calcined overnight at 400 C. The crucible with the dried contents was then covered with a lid and placed into a furnace at 1500 C. for 3 h.

(42) The resulting melt was poured onto a stainless steel table and roller quenched with a stainless steel roller. The sheet thickness was less than 1 mm, with 90% of the melt remaining glassy. The glassy parts, which had a brown color, were broken into smaller pieces and collected.

(43) The glass pieces (about 2525 mm) were placed onto silica disks and loaded into a box furnace for crystallization. The thermal cycle for crystallization involved heating at a rate of 10 C./min to 900 C. (hold time 2 h) and cooling at a rate of 5 C./min. After crystallization the glass-ceramic pieces were white, opaque and dense.

(44) Conductivity was measure by gold plating both sides of an 10 mm diameter disk. The conductivity of was 1.3610.sup.4 S/cm.

(45) A TGA scan, shown in FIG. 2, was performed in N.sub.2 at 10 C./min in a Pt pan. The Li.sub.1.3Nb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 material showed onset and peak crystallization temperatures of 664 C. and 668 C.

(46) The x-ray analysis of the material reveals that 71% was a rhombohedral Li(Al,Nb,Ti).sub.2((P,B)O.sub.3).sub.4 phase, 13% monoclinic Li.sub.3(Al,X,Ti).sub.2(PO.sub.4).sub.3, and 15% LiTi(PO.sub.4)O.

Example 2Li1.3Cr0.3Ge0.6Ti1.1(PO4)3

(47) Dry powders of lithium carbonate, chromium(III) oxide, germanium dioxide and titanium dioxide were mixed in a turbula mixer. The powder mix was poured into a Pt crucible and an aqueous solution of phosphoric acid was added to the dry mix and stirred to form a homogeneous slurry. The slurry was calcined overnight at 400 C. The crucible with the dried contents was then covered with a lid and placed into a furnace at 1500 C. for 3 h.

(48) The resulting melt was poured onto a stainless steel table and roller quenched with a stainless steel roller. The sheet thickness was less than 1 mm, with 75% of the melt remaining glassy. The glassy parts, which had a dark green color, were broken into smaller pieces and collected.

(49) The glass pieces (about 2525 mm) were placed onto silica disks and loaded into a box furnace for crystallization. The thermal cycle for crystallization involved heating at a rate of 10 C./min to 900 C. (hold time 2 h) and cooling at a rate of 5 C./min. After crystallization the glass-ceramic pieces were grass green, opaque and dense.

(50) Conductivity was measure by gold plating both sides of an 8 mm diameter disk. The conductivity of was 1.9910.sup.5 S/cm.

(51) A TGA scan, shown in FIG. 3, was performed in N.sub.2 at 10 C./min in a Pt pan. The Li.sub.1.3Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 material showed onset and peak crystallization temperatures of 691 C. and 697 C.

(52) The x-ray diffraction data are shown in FIG. 4. The primary phase (90%) is a rhombohedral Li(Cr,Ge,Ti).sub.2(PO.sub.3).sub.4 phase. The secondary phase (10%) was LiCrP.sub.2O.sub.7. In addition to the sample x-ray data, also shown in FIG. 4 are the index card data for lithium germanium phosphate and lithium chromium phosphate.

(53) An SEM micrograph of a cross-sectional fracture surface is shown in FIG. 5. The data reveal a uniform fine microstructure for Li.sub.1.3Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 crystallized at 900 C. without a discrete nucleation step.

Example 3 and 4

(54) Li.sub.1.6Cr.sub.0.6Ge.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3 and Li.sub.1.6Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 compositions were prepared in a manner consistent with the synthesis of Examples 1 and 2.

Example 5Li1.45Cr0.45Ge0.45Ti1.1(PO4)3

(55) Dry powders of lithium phosphate (monobasic), chromium(III) oxide, germanium dioxide and titanium dioxide were mixed in a turbula mixer. The powder mix was poured into a Pt crucible and an aqueous solution of phosphoric acid was added to the dry mix and stirred to form a homogeneous slurry. The slurry was calcined overnight at 400 C. The crucible with the calcined contents was then covered with a lid and placed into a furnace at 1500 C. for 3 h.

(56) The resulting melt was poured onto a stainless steel table and roller quenched with a stainless steel roller. The sheet thickness was less than 1 mm, with 80% of the melt remaining glassy. The glassy parts, which had a dark green color, were broken into smaller pieces and collected.

(57) The glass pieces (about 2525 mm) were placed onto silica disks and loaded into a box furnace for crystallization. The thermal cycle for crystallization involved heating at a rate of 10 C./min to 900 C. (hold time 2 h) and cooling at a rate of 5 C./min. After crystallization the glass-ceramic pieces were grass green, opaque and dense.

(58) Conductivity was measure by gold plating both sides of an 8 mm diameter disk. The conductivity of was 2.4110.sup.4 S/cm.

(59) A TGA scan, shown in FIG. 6, was performed in N.sub.2 at 10 C./min in a Pt pan. The Li.sub.1.45Cr.sub.0.45Ge.sub.0.45Ti.sub.1.1(PO.sub.4).sub.3 material showed onset and peak crystallization temperatures of 712 C. and 726 C.

(60) An X-ray diffraction trace is shown in FIG. 7. The primary (90%) glass-ceramic phase indexes to Li.sub.1.45Cr.sub.0.45Ge.sub.0.45Ti.sub.1.1(PO.sub.4).sub.3. The secondary (10%) phase was LiCrP.sub.2O.sub.7.

Example 6Stability Evaluation

(61) The water stability of Examples 1-4 was evaluated by measuring weight loss as a function of exposure (submersion) in de-ionized water at room temperature for up to 168 h (1 week). Weight loss as a function of time is shown in FIG. 8.

(62) The compositions of Examples 1-3 (Li.sub.1.3Nb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15, Li.sub.1.3Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 and Li.sub.1.6Cr.sub.0.6Ge.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3) displayed good stability out to 168 h. The boron-free and chromium-containing Example 3 showed a maximum weight less of less than 1%, while the boron-containing and chromium-containing Example 4 (Li.sub.1.6Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15) had a weight loss of greater than 12% at about 25 h. It will be appreciated that the inclusion of boron in the compositions does not per se increase the water solubitity. Example 1 exhibited demonstrably good water stability as compared with Example 4, though both included equivalent amounts of BO.sub.4.

(63) The thermal history and select properties of exemplary compositions are given in Table 2. The glass formability of the compositions upon roller quenching is measured on a scale from 0 to 5, where a glass formability index of 0 corresponds to substantially no glass content (i.e., fully crystalline) following quenching and a glass formability index of 5 corresponds to a completely glassy or substantially completely glassy roller-quenched sheet.

(64) A glass characterized by a glass formability index of 5 includes 85 to 100 vol. % glassy phase. A glass formability index of 4 corresponds to a roller quenched glass having from 65% up to 85 vol. % glassy phase. A glass formability index of 3 corresponds to a roller quenched sample having from 40% up to 65 vol. % glassy phase. A glass formability index of 2 corresponds to a roller quenched sample having from 15% up to 40 vol. % glassy phase. A glass formability index of 1 corresponds to a roller quenched sample having from 5% up to 15 vol. % glassy phase. A glass formability index of 0 corresponds to a roller quenched sample having less than 5 vol. % glassy phase.

(65) The heat treatment data include both the nucleation temperature and time (T/t) and the crystallization temperature and time. The conductivity listed is that of the glass-ceramic formed using the reported heat treatment. The glass-ceramics disclosed herein may have a lithium ion conductivity of at least 110.sup.4 S/cm.

(66) The glass transition temperature (T.sub.g) and crystallization peak temperature (T.sub.x) of the parent glass are also listed.

(67) TABLE-US-00002 TABLE 2 Thermal history and properties of glass and glass-ceramic compositions. Heat treatment Glass nucleation T t Conductivity formability T/t [ C.]/[h] [ C.] [h] [S/cm] T.sub.g [ C.] T.sub.x [ C.] Zn.sub.0.25Li.sub.0.5Fe.sub.0.7Nb.sub.0.7Ti.sub.0.6(PO.sub.4).sub.3 4 525/1 800 2 1.0E06 LiFe.sub.0.7Nb.sub.0.7Ti.sub.0.6(PO.sub.4).sub.3 3 525/1 800 2 2.0E07 Zn.sub.0.15LiFe.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 3 550 800 2 1.0E07 629 Zn.sub.0.25Li.sub.0.8Fe.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 3 550 800 2 1.0E07 635 Li.sub.1.3Nb.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 4 658 Zn.sub.0.15LiNb.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 5 550 800 2 3.2E07 663 Zn.sub.0.25Li.sub.0.8Nb.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 4 550 800 2 8.5E07 675 Zn.sub.0.4LiAl.sub.0.8Ti.sub.1.2(PO.sub.4).sub.3 4 550 800 2 1.7E06 621 Zn.sub.0.3LiCr.sub.0.3Al.sub.0.3Ti.sub.1.4(PO.sub.4).sub.3 3 550 800 2 5.3E07 672 Zn.sub.0.3Li.sub.1.3Fe.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 3 900 2 4.2E06 581 Li.sub.1.3Cr.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 3 678/1 900 6 2.2E05 714 LiNb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.3 5 676/1 900 2 1.6E05 623 721 Li.sub.0.95Nb.sub.0.4Al.sub.0.35Ti.sub.1.25(PO.sub.4).sub.3 3 900 2 9.2E07 704 LiNb.sub.0.6Al.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3 4 900 2 1.5E05 616 697 Li.sub.1.6Fe.sub.0.3Nb.sub.0.3Al.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3 4 558/1 700 2 7.8E07 533 592 Li.sub.1.3V.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 3 900 2 1.1E05 564 626 Li.sub.0.7V.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 4 645/1 900 2 4.9E07 717 Li.sub.1.3Nb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 4 900 2 1.4E04 597 668 (example 1) Li.sub.1.6Nb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.2.7(BO.sub.4).sub.0.3 5 611 900 2 6.9E06 570 646 Li.sub.1.3Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 (example 2) 4 900 2 4.8E05 625 697 Li.sub.1.3Cr.sub.0.3Ge.sub.0.9Ti.sub.0.8(PO.sub.4).sub.3 5 900 2 2.0E05 605 701 Li.sub.1.4Fe.sub.0.3Nb.sub.0.3Al.sub.0.4Ti.sub.1.0(PO.sub.4).sub.3 3 500/1 900 3 9.3E07 567 614 Li.sub.1.4Fe.sub.0.4Nb.sub.0.4Al.sub.0.4Ti.sub.0.8(PO.sub.4).sub.3 3 500/1 900 3 5.0E07 537 607 Li.sub.1.6Cr.sub.0.6Ge.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3 (example 3) 4 900 2 9.3E05 653 733 Li.sub.1.6Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 4 500/1 900 2 2.8E04 622 681 (example 4) Li.sub.1.4Cr.sub.0.4Ge.sub.0.4Ti.sub.1.2(PO.sub.4).sub.3 3 500/1 900 2 1.3E05 622 675 Li.sub.1.6Cr.sub.0.3Al.sub.0.3Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 4 500/1 900 2 8.5E05 646 687 LiNb.sub.0.45Al.sub.0.45Ge.sub.0.2Ti.sub.0.9(PO.sub.4).sub.3 5 900 2 1.4E04 550 637 Li.sub.1.9Cr.sub.0.6Ge.sub.0.6Ti.sub.0.8(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 3 900 2 2.4E05 613 705 Li.sub.1.6Cr.sub.0.6Si.sub.0.1Ti.sub.1.3(PO.sub.4).sub.3 3 900 2 7.0E06 651 742 Li.sub.1.9Cr.sub.0.6Si.sub.0.1Ti.sub.1.3(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 3 900 2 1.7E04 724 Li.sub.1.9Cr.sub.0.3Al.sub.0.3Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 3 900 2 5.8E05 573 664 Li.sub.1.8Cr.sub.0.4Al.sub.0.4Ge.sub.0.3Ti.sub.0.9(PO.sub.4).sub.3 4 900 2 2.7E05 594 684 Li.sub.2.1Cr.sub.0.4Al.sub.0.4Ge.sub.0.3Ti.sub.0.9(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 4 900 2 1.7E06 577 665 Li.sub.1.6Cr.sub.0.6Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 3 900 2 1.0E05 654 730 Li.sub.1.9Cr.sub.0.6Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 3 900 2 2.5E10 620 695 Li.sub.1.3Nb.sub.0.45Al.sub.0.45Ge.sub.0.2Ti.sub.0.9(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 4 5.19E05 591 677 LiNb.sub.0.3Al.sub.0.3Ge.sub.0.2Ti.sub.1.2(PO.sub.4).sub.3 4 1.09E06 639 705 Li.sub.1.3Fe.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 3 1.30E06 569 631 Li.sub.1.6Cr.sub.0.3Si.sub.0.6Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 5 4.44E06 673 Li.sub.1.1Cr.sub.0.1Ge.sub.0.8Ti.sub.1.1(PO.sub.4).sub.3 3 1.13E05 629 699 Li.sub.1.2Cr.sub.0.2Ge.sub.0.7Ti.sub.1.1(PO.sub.4).sub.3 4 2.98E05 635 715 Li.sub.1.4Cr.sub.0.4Ge.sub.0.5Ti.sub.1.1(PO.sub.4).sub.3 4 7.15E05 633 718 Li.sub.1.5Cr.sub.0.5Ge.sub.0.4Ti.sub.1.1(PO.sub.4).sub.3 5 3.12E04 604 728 Li.sub.1.7Cr.sub.0.7Ge.sub.0.2Ti.sub.1.1(PO.sub.4).sub.3 3 3.21E05 670 739 Li.sub.1.7Cr.sub.0.7Ge.sub.0.7Ti.sub.0.6(PO.sub.4).sub.3 5 6.05E05 628 739 Li.sub.1.45Cr.sub.0.45Ge.sub.0.45Ti.sub.1.1(PO.sub.4).sub.3 (example 5) 4 2.41E04 648 726 Li.sub.1.3Cr.sub.0.3Ge.sub.0.5Ti.sub.1.2(PO.sub.4).sub.3 3 3.83E05 652 716 Li.sub.1.6Cr.sub.0.6Ge.sub.0.4Ti.sub.1.0(PO.sub.4).sub.3 3 8.20E06 642 725 Li.sub.1.7Cr.sub.0.7Ge.sub.0.4Ti.sub.0.9(PO.sub.4).sub.3 3 3.08E06 657 734 Li.sub.1.8Cr.sub.0.8Ge.sub.0.4Ti.sub.0.8(PO.sub.4).sub.3 3 1.83E05 652 741 Li.sub.1.5Cr.sub.0.5Ge.sub.0.3Ti.sub.1.2(PO.sub.4).sub.3 3 5.83E06 645 719 Li.sub.1.5Cr.sub.0.5Ge.sub.0.5Ti.sub.1.0(PO.sub.4).sub.3 4 1.47E04 643 721 Li.sub.1.5Cr.sub.0.5Ge.sub.0.7Ti.sub.0.8(PO.sub.4).sub.3 4 1.45E04 636 720 Li.sub.1.5Cr.sub.0.5Ge.sub.0.8Ti.sub.0.7(PO.sub.4).sub.3 3 1.06E04 645 724 Li.sub.1.55Cr.sub.0.55Ge.sub.0.35Ti.sub.1.1(PO.sub.4).sub.3 3 1.55E04 633 720

(68) Crystallographic data for the glass-ceramic materials are summarized in Table 3.

(69) TABLE-US-00003 TABLE 3 Crystallographic properties of glass-ceramic compositions rhombohedral phase [%] a [nm] c [nm] Zn.sub.0.25Li.sub.0.5Fe.sub.0.7Nb.sub.0.7Ti.sub.0.6(PO.sub.4).sub.3 LiFe.sub.0.7Nb.sub.0.7Ti.sub.0.6(PO.sub.4).sub.3 Zn.sub.0.15LiFe.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 99 8.5189 20.991 Zn.sub.0.25Li.sub.0.8Fe.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 92 8.5289 21.061 Li.sub.1.3Nb.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 99 8.4929 20.8941 Zn.sub.0.15LiNb.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 86 8.5145 20.9407 Zn.sub.0.25Li.sub.0.8Nb.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 82 8.5235 21.005 Zn.sub.0.4LiAl.sub.0.8Ti.sub.1.2(PO.sub.4).sub.3 69 8.4819 20.834 Zn.sub.0.3LiCr.sub.0.3Al.sub.0.3Ti.sub.1.4(PO.sub.4).sub.3 8.5018 20.8811 Zn.sub.0.3Li.sub.1.3Fe.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 71 8.5024 20.931 Li.sub.1.3Cr.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 82 8.5162 20.9521 LiNb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.3 88 8.5017 20.9558 Li.sub.0.95Nb.sub.0.4Al.sub.0.35Ti.sub.1.25(PO.sub.4).sub.3 53 8.503 21.023 LiNb.sub.0.6Al.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3 98 8.5087 21.032 Li.sub.1.6Fe.sub.0.3Nb.sub.0.3Al.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3 59 8.5082 20.999 Li.sub.1.3V.sub.0.3Al.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 78 8.4599 20.786 Li.sub.0.7V.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 76 8.5213 21.086 Li.sub.1.3Nb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 71 8.4964 20.9045 (example 1) Li.sub.1.6Nb.sub.0.45Al.sub.0.45Ti.sub.1.1(PO.sub.4).sub.2.7(BO.sub.4).sub.0.3 37 8.4935 20.587 Li.sub.1.3Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.3 91 8.4338 20.7689 (example 2) Li.sub.1.3Cr.sub.0.3Ge.sub.0.9Ti.sub.0.8(PO.sub.4).sub.3 88 8.3909 20.7361 Li.sub.1.4Fe.sub.0.3Nb.sub.0.3Al.sub.0.4Ti.sub.1.0((PO.sub.4).sub.3 72 8.52125 20.9194 Li.sub.1.4Fe.sub.0.4Nb.sub.0.4Al.sub.0.4Ti.sub.0.8(PO.sub.4).sub.3 73 8.5327 20.9841 Li.sub.1.6Cr.sub.0.6Ge.sub.0.6Ti.sub.0.8(PO.sub.4).sub.3 74 8.4372 20.865 (example 3) Li.sub.1.6Cr.sub.0.3Ge.sub.0.6Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 78 8.46712 20.8045 (example 4) Li.sub.1.4Cr.sub.0.4Ge.sub.0.4Ti.sub.1.2(PO.sub.4).sub.3 83 8.468 20.857 Li.sub.1.6Cr.sub.0.3Al.sub.0.3Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 79 8.4559 20.7978 LiNb.sub.0.45Al.sub.0.45Ge.sub.0.2Ti.sub.0.9(PO.sub.4).sub.3 84 8.39563 20.6508 Li.sub.1.9Cr.sub.0.6Ge.sub.0.6Ti.sub.0.8(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 76 8.3727 21.4079 Li.sub.1.6Cr.sub.0.6Si.sub.0.1Ti.sub.1.3(PO.sub.4).sub.3 57 8.485 21.189 Li.sub.1.9Cr.sub.0.6Si.sub.0.1Ti.sub.1.3(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 98 8.486 21.341 Li.sub.1.9Cr.sub.0.3Al.sub.0.3Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 81 Li.sub.1.8Cr.sub.0.4Al.sub.0.4Ge.sub.0.3Ti.sub.0.9(PO.sub.4).sub.3 79 8.397 21.326 Li.sub.2.1Cr.sub.0.4Al.sub.0.4Ge.sub.0.3Ti.sub.0.9(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 77 8.383 21.602 Li.sub.1.6Cr.sub.0.6Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.3 70 8.464 21.257 Li.sub.1.9Cr.sub.0.6Ge.sub.0.3Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 82 8.456 21.364 Li.sub.1.3Nb.sub.0.45Al.sub.0.45Ge.sub.0.2Ti.sub.0.9(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 98.4 8.49 20.97 LiNb.sub.0.3Al.sub.0.3Ge.sub.0.2Ti.sub.1.2(PO.sub.4).sub.3 100 8.4809 20.9277 Li.sub.1.3Fe.sub.0.3Nb.sub.0.3Al.sub.0.3Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 100 8.52607 20.9291 Li.sub.1.6Cr.sub.0.3Si.sub.0.6Ti.sub.1.1(PO.sub.4).sub.2.85(BO.sub.4).sub.0.15 100 8.50379 20.9351 Li.sub.1.1Cr.sub.0.1Ge.sub.0.8Ti.sub.1.1(PO.sub.4).sub.3 96 8.40972 20.7612 Li.sub.1.2Cr.sub.0.2Ge.sub.0.7Ti.sub.1.1(PO.sub.4).sub.3 92 8.41757 20.7879 Li.sub.1.4Cr.sub.0.4Ge.sub.0.5Ti.sub.1.1(PO.sub.4).sub.3 89 8.44437 20.8261 Li.sub.1.5Cr.sub.0.5Ge.sub.0.4Ti.sub.1.1(PO.sub.4).sub.3 88 8.4569 20.8598 Li.sub.1.7Cr.sub.0.7Ge.sub.0.2Ti.sub.1.1(PO.sub.4).sub.3 Li.sub.1.7Cr.sub.0.7Ge.sub.0.7Ti.sub.0.6(PO.sub.4).sub.3 Li.sub.1.45Cr.sub.0.45Ge.sub.0.45Ti.sub.1.1(PO.sub.4).sub.3 90 8.4501 20.8343 (example 5) Li.sub.1.3Cr.sub.0.3Ge.sub.0.5Ti.sub.1.2(PO.sub.4).sub.3 90 8.4434 20.8073 Li.sub.1.6Cr.sub.0.6Ge.sub.0.4Ti.sub.1.0(PO.sub.4).sub.3 88 8.457 20.860 Li.sub.1.7Cr.sub.0.7Ge.sub.0.4Ti.sub.0.9(PO.sub.4).sub.3 87 8.454 20.850 Li.sub.1.8Cr.sub.0.8Ge.sub.0.4Ti.sub.0.8(PO.sub.4).sub.3 85 8.453 20.825 Li.sub.1.5Cr.sub.0.5Ge.sub.0.3Ti.sub.1.2(PO.sub.4).sub.3 91 8.472 20.875 Li.sub.1.5Cr.sub.0.5Ge.sub.0.5Ti.sub.1.0(PO.sub.4).sub.3 90 8.441 20.845 Li.sub.1.5Cr.sub.0.5Ge.sub.0.7Ti.sub.0.8(PO.sub.4).sub.3 89 8.414 20.799 Li.sub.1.5Cr.sub.0.5Ge.sub.0.8Ti.sub.0.7(PO.sub.4).sub.3 91 8.461 20.879 Li.sub.1.55Cr.sub.0.55Ge.sub.0.35Ti.sub.1.1(PO.sub.4).sub.3 89 8.397 20.785

(70) Embodiments relate to a glass-ceramic solid electrolyte. The glass-ceramic may have a lithium ion conductivity of at least 110.sup.4 S/cm. The solid electrolyte may be incorporated into an energy storage device such as a fuel cell or a lithium-ion battery.

(71) As used herein, the singular forms a, an and the include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a glass includes examples having two or more such glasses unless the context clearly indicates otherwise.

(72) Ranges can be expressed herein as from about one particular value, and/or to about another particular value. When such a range is expressed, examples include from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent about, it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

(73) Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not actually recite an order to be followed by its steps or it is not otherwise specifically stated in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that any particular order be inferred.

(74) It is also noted that recitations herein refer to a component being configured or adapted to function in a particular way. In this respect, such a component is configured or adapted to embody a particular property, or function in a particular manner, where such recitations are structural recitations as opposed to recitations of intended use. More specifically, the references herein to the manner in which a component is configured or adapted to denotes an existing physical condition of the component and, as such, is to be taken as a definite recitation of the structural characteristics of the component.

(75) While various features, elements or steps of particular embodiments may be disclosed using the transitional phrase comprising, it is to be understood that alternative embodiments, including those that may be described using the transitional phrases consisting or consisting essentially of, are implied. Thus, for example, implied alternative embodiments to a glass or glass-ceramic composition that comprises particular constituents include embodiments where the composition consists of the constituents and embodiments where the composition consists essentially of the constituents.

(76) It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention. Since modifications, combinations, sub-combinations and variations of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and their equivalents.