Sulfide-based solid electrolyte for lithium ion batteries
Proposed is a new sulfide-based solid electrolyte for lithium ion batteries, the sulfide-based solid electrolyte relating to a compound that has a cubic argyrodite type crystal structure and is represented by Li 7-x-2y PS 6-x-y Cl x , and having excellent water resistance and oxidation resistance. Proposed is a sulfide-based solid electrolyte for lithium ion batteries, the sulfide-based solid electrolyte containing a compound that has a cubic argyrodite type crystal structure and is represented by compositional formula (1): Li 7-x-2y PS 6-x-y Cl x , in which compositional formula, conditions: 0.8≦x≦1.7 and 0<y≦−0.25x+0.5 are satisfied.
1. A sulfide-based solid electrolyte for lithium ion batteries comprising a compound having a cubic argyrodite type crystal structure, wherein the compound is represented by compositional formula (1): Li 7-x-2y PS 6-x-y Cl x , and in the compositional formula (1), conditions: 0.8≦x≦1.7 and 0<y≦−0.25x+0.5 are satisfied.
2. The sulfide-based solid electrolyte for lithium ion batteries according to claim 1 , wherein in the compositional formula (1), conditions: 1.0≦x≦1.4 and 0<y≦−0.2x+0.4 are further satisfied.
3. The sulfide-based solid electrolyte for lithium ion batteries according to claim 1 , wherein in the compositional formula (1), condition: 0.15≧[y/(2−x)] is further satisfied.
4. The sulfide-based solid electrolyte for lithium ion batteries according to claim 1 , wherein the sulfide-based solid electrolyte is obtained by mixing a lithium sulfide (Li 2 S) powder, a phosphorus sulfide (P 2 S 5 ) powder, and a lithium chloride (LiCl) powder, and calcining the mixture at 350° C. to 500° C. in an inert atmosphere, or calcining the mixture at 350° C. to 650° C. in an atmosphere containing hydrogen sulfide gas.
5. A lithium ion battery comprising the solid electrolyte according to claim 1 .
6. A lithium ion battery comprising a negative electrode active material containing the solid electrolyte according to claim 1 and carbon.
7. The sulfide-based solid electrolyte for lithium ion batteries according to claim 2 , wherein in the compositional formula (1), condition: 0.15≧[y/(2−x)] is further satisfied.
8. The sulfide-based solid electrolyte for lithium ion batteries according to claim 2 , wherein the sulfide-based solid electrolyte is obtained by mixing a lithium sulfide (Li 2 S) powder, a phosphorus sulfide (P 2 S 5 ) powder, and a lithium chloride (LiCl) powder, and calcining the mixture at 350° C. to 500° C. in an inert atmosphere, or calcining the mixture at 350° C. to 650° C. in an atmosphere containing hydrogen sulfide gas.
9. The sulfide-based solid electrolyte for lithium ion batteries according to claim 3 , wherein the sulfide-based solid electrolyte is obtained by mixing a lithium sulfide (Li 2 S) powder, a phosphorus sulfide (P 2 S 5 ) powder, and a lithium chloride (LiCl) powder, and calcining the mixture at 350° C. to 500° C. in an inert atmosphere, or calcining the mixture at 350° C. to 650° C. in an atmosphere containing hydrogen sulfide gas.
10. A lithium ion battery comprising the solid electrolyte according to claim 2 .
11. A lithium ion battery comprising the solid electrolyte according to claim 3 .
12. A lithium ion battery comprising the solid electrolyte according to claim 4 .
13. A lithium ion battery comprising a negative electrode active material containing the solid electrolyte according to claim 2 and carbon.
14. A lithium ion battery comprising a negative electrode active material containing the solid electrolyte according to claim 3 and carbon.
15. A lithium ion battery comprising a negative electrode active material containing the solid electrolyte according to claim 4 and carbon.