Sulfide solid electrolyte

Patent metadata

Field	Value
Publication number	US-2018069262-A1
Application number	US-201715672462-A
Country	US
Kind code	A1
Filing date	Aug 9, 2017
Priority date	Sep 8, 2016
Publication date	Mar 8, 2018
Grant date	—

Abstract

Aimed at providing a sulfide solid electrolyte comprising an argyrodite type crystal structure, having a high ionic conductivity due to presence of a large amount of a halogen element and is capable of suppressing agglomeration at the time of production. Provided is a sulfide solid electrolyte comprising lithium, phosphorus, sulfur and one or more elements X selected from halogen elements, wherein the sulfide solid electrolyte comprises an argyrodite type crystal structure, and wherein a molar ratio of the lithium to the phosphorus “a (Li/P)”, a molar ratio of the sulfur to the phosphorus “b (S/P)” and a molar ratio of the element X to the phosphorus “c (X/P)” satisfy the following formulas (1) to (3):
5.05≦ a <7.3  (1)

0.705≦ a−b <1.0  (2)

7.0< a+c ≦7.3  (3)

provided that b>0 and c>0.

First claim

1 : A sulfide solid electrolyte, comprising
lithium, phosphorus, sulfur and one or more elements X selected from the group consisting of a halogen element, wherein the sulfide solid electrolyte comprises an argyrodite type crystal structure, and the sulfide solid electrolyte satisfies formulae (1) to (3):
5.05≦ a< 7.3  (1)

0.705≦ a−b< 1.0  (2)

7.0< a+c≦ 7.3  (3)

wherein a represents a molar ratio of the lithium to the phosphorus, b represents a molar ratio of the sulfur to the phosphorus, c represents a molar ratio of the element X to the phosphorus, and b>0 and c>0.

2 : The sulfide solid electrolyte according to claim 1 , that satisfies a composition represented by formula (4):
Li a (P 1−z M z )S b X c   (4)
wherein M is one or more elements selected from the group consisting of Si, Ge, Sn, Pb, B, Al, Ga, As, Sb and Bi, X is one or more elements selected from the group consisting of F, Cl, Br and I; a to c satisfy the formulae (1) to (3); and z satisfies 0≦z≦0.3.

3 : The sulfide solid electrolyte according to claim 1 , wherein the sulfide solid electrolyte has a diffraction peak at 2θ=25.2±0.5 deg and a diffraction peak 29.7±0.5 deg in powder X-ray diffraction using CuKα rays.

4 : An electrode mix, comprising:
the sulfide solid electrolyte according to claim 1 and an active material.

5 : A lithium ion battery, comprising at least one of:
the sulfide solid electrolyte according to claim 1 , and an electrode mix comprising the sulfide solid electrolyte and an active material.

6 : An electrode mix, comprising:
the sulfide solid electrolyte according to claim 1 .

7 : A lithium ion battery, comprising: at least one of:
the sulfide solid electrolyte according to claim 1 , an electrode mix comprising the sulfide solid electrolyte and an active material and an electrode mix comprising the sulfide solid electrolyte.

Assignees

• Idemitsu Kosan Co

Inventors

• Utsuno Futoshi
• Terai Kota

Classifications

• H01M10/0562 Primary

  Solid materials · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M2300/0065

  Solid electrolytes · CPC title

• H01M4/36

  Selection of substances as active materials, active masses, active liquids · CPC title

• H01M2300/0068

  inorganic · CPC title