Sulfide-based solid electrolyte for lithium ion batteries

• US 9,899,701 B2
• Filed: 06/15/2015
• Issued: 02/20/2018
• Est. Priority Date: 07/16/2014
• Status: Active Grant

• Current Assignee: Mitsui Mining and Smelting Company Limited
• Original Assignee: Mitsui Mining and Smelting Company Limited
• Inventors: Miyashita, Norihiko, Chikumoto, Takashi, Matsushima, Hideaki, Matsuzaki, Kenji
• Primary Examiner(s): APICELLA, KARIE O
• Application Number:
  US15/326,238
• Publication Number:
  US 20170222257A1
• Time in Patent Office: 981 Days
• CPC Class Codes: C01B 25/14 Sulfur, selenium, or tellurium compounds of phosphorus
• CPC Class Codes: C01P 2002/30 Three-dimensional structures
• CPC Class Codes: C01P 2006/40 Electric properties
• CPC Class Codes: H01B 1/06 mainly consisting of other non-metallic substances
• CPC Class Codes: H01B 1/10 sulfides
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0562 Solid materials
• CPC Class Codes: H01M 2300/008 Halides
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

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-2yPS_6-x-yCl_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-2yPS_6-x-yCl_x, in which compositional formula, conditions: 0.8≦x≦1.7 and 0<y≦−0.25x+0.5 are satisfied.

Claims

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-2yPS_6-x-yCl_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 (Li₂S) powder, a phosphorus sulfide (P₂S₅) 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 (Li₂S) powder, a phosphorus sulfide (P₂S₅) 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 (Li₂S) powder, a phosphorus sulfide (P₂S₅) 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.