Sulfide solid electrolyte and method of producing the same
Disclosed is a sulfide solid electrolyte of high robustness in its production step and of high lithium ion conductivity, the sulfide solid electrolyte including Li, P, S, Br, I, and N as its constituent elements.
1. A method of producing a sulfide solid electrolyte comprising:
amorphizing a raw material composition that contains Li 2 S, P 2 S 5 , LiI, LiBr, and Li 3 N to obtain a solid electrolyte glass; and
heating the solid electrolyte glass at a temperature of from 240° C. to 270° C. to produce the sulfide solid electrolyte comprising Li, P, S, Br, I, and N as its constituent elements,
wherein the raw material composition contains greater than 0 mol % and no more than 3.82 mol % of Li 3 N, assuming that the total of Li 2 S, P 2 S 5 , LiI, LiBr, and Li 3 N is 100 mol %.
2. The method according to claim 1 , wherein the raw material composition contains greater than 0 mol % and no more than 2.66 mol % of Li 3 N, assuming that the total of Li 2 S, P 2 S 5 , LiI, LiBr, and Li 3 N is 100 mol %.
3. The method according to claim 1 , where the sulfide solid electrolyte has a lithium ion conductivity of no less than 5.2 mS/cm.
4. A method of producing a sulfide solid electrolyte, the method comprising:
amorphizing a raw material composition to produce a solid electrolyte glass, the raw material composition comprising:
25.9 wt. % Li 2 S;
44.8 wt. % P 2 S 5 ;
14.3 wt. % LiI;
13.9 wt. % LiBr; and
1.0 wt. % Li 3 N, where the wt. % is based on the total weight of Li 2 S, P 2 S 5 , LiI, LiBr, and Li 3 N; and
heating the solid electrolyte glass at a temperature of from 240° C. to 270° C. to produce the sulfide solid electrolyte, where the sulfide solid electrolyte has a lithium ion conductivity of no less than 5.2 mS/cm and wherein the sulfide solid electrolyte comprises Li, P, S, Br, I, and N as its constituent elements.