Sulfide solid electrolyte and all-solid-state battery

Patent metadata

Field	Value
Publication number	US-2021218056-A1
Application number	US-201917270728-A
Country	US
Kind code	A1
Filing date	Aug 30, 2019
Priority date	Aug 30, 2018
Publication date	Jul 15, 2021
Grant date	—

Abstract

An aspect of the present invention is a sulfide solid electrolyte that contains at least one element M selected from the group consisting of Al, Si, B, Mg, Zr, Ti, Hf, Ca, Sr, Sc, Ce, Ta, Nb, W, Mo, and V, and N and has a crystalline structure. Another aspect of the present invention is a sulfide solid electrolyte that contains Al and N and that has a crystalline structure.

First claim

1 . A sulfide solid electrolyte comprising at least one element M selected from the group consisting of Al, Si, B, Mg, Zr, Ti, Hf, Ca, Sr, Sc, Ce, Ta, Nb, W, Mo, and V, and N, and having a crystalline structure.

2 . A sulfide solid electrolyte according to claim 1 , wherein the at least one element M includes Al.

3 . The sulfide solid electrolyte according to claim 1 , wherein the crystalline structure includes a crystalline structure that has a crystal phase of Li 7 P 3 S 11 , Li 4 P 2 S 6 , or β-Li 3 PS 4 , or a first crystalline structure that has diffraction peaks at 2θ=17.9°±0.5°, 19.1°±0.5°, 29.1°±0.5°, and 29.8°±0.5° in X-ray diffraction measurement with a CuKα line.

4 . The sulfide solid electrolyte according to claim 3 , wherein the first crystalline structure includes a specific crystalline structure A that has diffraction peaks at 2θ=17.9°±0.5°, 19.1°±0.5°, 29.1°±0.5°, 29.8°±0.5°, and 30.9°±0.5° in the X-ray diffraction measurement, or a specific crystalline structure B that has diffraction peaks at 2θ=17.9°±0.5°, 19.1°±0.5°, 29.1°±0.5°, and 29.8°±0.5° and has no diffraction peak at 30.9°±0.5° in the X-ray diffraction measurement.

5 . The sulfide solid electrolyte according to claim 1 , comprising Li, P, S, N, and at least one element M selected from the group consisting of Al, Si, B, Mg, Zr, Ti, Hf, Ca, Sr, Sc, Ce, Ta, Nb, W, Mo, and V,
wherein a content ratio of the Li to the P is 1.64 or more and 4.00 or less in terms of mole ratio, and a content ratio of the N to the P is 0.02 or more and 1.11 or less in terms of mole ratio.

6 . The sulfide solid electrolyte according to claim 5 , wherein the content ratio of the Li to the P is 2.77 or more and 3.38 or less in terms of mole ratio, and the content ratio of the N to the P is 0.28 or more and 0.65 or less in terms of mole ratio.

7 . The sulfide solid electrolyte according to claim 1 , wherein the sulfide solid electrolyte has a composition represented by a general formula (100−z)(yLi 2 S.(1−y)P 2 S 5 ).zLi α M β N (where 0<z≤40, 0.50≤y≤0.75, α and β represent numerical values that provide stoichiometric ratios depending on a type of the element M).

8 . The sulfide solid electrolyte according to claim 1 , further comprising Ge.

9 . The sulfide solid electrolyte according to claim 8 , wherein the crystalline structure includes a crystalline structure that has a crystal phase of Li 10 GeP 2 S 12 .

10 . The sulfide solid electrolyte according to claim 8 , comprising Li, P, S, N, Ge, and the element M,
wherein a content ratio of the Li to the P is 5.01 or more and 5.61 or less in terms of mole ratio, and a content ratio of the N to the P is 0.0051 or more and 0.41 or less in terms of mole ratio.

11 . The sulfide solid electrolyte according to claim 8 , wherein the sulfide solid electrolyte has a composition represented by a general formula (100−z)Li 10 GeP 2 S 12 .zLi α M β N (where 0<z≤50, α and β represent numerical values that provide stoichiometric ratios depending on a type of the element M).

12 . The sulfide solid electrolyte according to claim 1 , wherein an ion conductivity at 25° C. is 1.0×10 −3 S/cm or more.

13 . An all-solid-state battery comprising:
a negative electrode layer; a solid electrolyte layer; and a positive electrode layer, wherein the negative electrode layer, the solid electrolyte layer, the positive electrode layer, or a combination thereof contains the sulfide solid electrolyte according to claim 1 .

Assignees

• Gs Yuasa Int Ltd

Inventors

• Fukushima Akihiro
• Sakuma Ryo
• Kakeya Tadashi

Classifications

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• H01M4/13

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M2300/0068

  inorganic · CPC title

• H01M10/0562 Primary

  Solid materials · CPC title