Sulfide solid electrolyte material, battery, and method for producing sulfide solid electrolyte material

Patent metadata

Field	Value
Publication number	US-10305140-B2
Application number	US-201514710987-A
Country	US
Kind code	B2
Filing date	May 13, 2015
Priority date	May 15, 2014
Publication date	May 28, 2019
Grant date	May 28, 2019

Abstract

An object of the present invention is to provide a sulfide solid electrolyte material having satisfactory ion conductivity. In the present invention, the above object is solved by providing a sulfide solid electrolyte material comprising a Li element, a Si element, a P element, a S element, and an X element (in which X represents at least one of F, Cl, Br and I), the sulfide solid electrolyte material having a crystal phase B having a peak at the position of 2θ=30.12°±1.00° measured by X-ray diffractometry using CuKα ray.

First claim

What is claimed is:

1. A sulfide solid electrolyte material, comprising a Li element, a Si element, a P element, a S element, and an X element (in which X represents at least one of F, Cl, Br and I),
wherein the sulfide solid electrolyte material has a crystal phase B that has peaks at positions of 2θ=15.60° ±1.00°, 18.04° ±1.00°, 25.60° ±1.00°, 30.12°±1.00°, and 31.46° ±1.00°, and that does not have a peak at a position of 27.33° ±1.00°, measured by X-ray diffractometry using CuKαray,
wherein when the diffraction intensity of the peak of 2θ=30.12° ±1.00° is designated as I 1 , and the diffraction intensity of the peak of 2θ=31.46° ±1.00° is designated as I 2 , a value of a ratio I 1 /I 2 is in a range of 1.4 to 2.8, and
wherein the sulfide solid electrolyte material has a composition of y(LiX)·(100−y) (Li (4-x) Si (1-x) P x S 4 ), in which x satisfies the relationship: 0.55≤×≤0.7, and y satisfies the relationship: 20≤y ≤60.

2. The sulfide solid electrolyte material according to claim 1 , wherein the sulfide solid electrolyte material has a crystal phase A having a peak at a position of 2θ=29.58°±1.00° measured by X-ray diffractometry using CuKαray.

3. The sulfide solid electrolyte material according to claim 2 , wherein when a diffraction intensity of the peak at 2θ=29.58° ±1.00° is designated as I A , and a diffraction intensity of the peak at 2θ=30.12° ±1.00° is designated as I B , a value of a ratio I A /I B is 1.3 or less.

4. The sulfide solid electrolyte material according to claim 1 , wherein x satisfies the relationship: x =0.6.

5. The sulfide solid electrolyte material according to claim 1 , wherein η represented by the following formula satisfies the relationship: 8.2≤η≤9.5:
η=Σ I=1 N V I m I /Σm α ,

in which v I represents a valence of cationic elements comprising the Li element, the Si element, and the P element; m I represents a number of moles of the cationic element; N represents a total number of cation species included in the sulfide solid electrolyte material; and m α represents a number of moles of cationic elements excluding the Li element.

6. The sulfide solid electrolyte material according to claim 1 , wherein γ represented by the following formula satisfies the relationship: 3.6≤γ≤4.9:
γ=m Li /Σm α ,

in which m Li represents a number of moles of the Li element; and m α represents a number of moles of cationic elements comprising the Si element and the P element, and excluding the Li element.

7. The sulfide solid electrolyte material according to claim 1 , wherein X represents Cl.

8. A battery comprising a cathode active material layer containing a cathode active material; an anode active material layer containing an anode active material; and an electrolyte layer formed between the cathode active material layer and the anode active material layer,
wherein at least one of the cathode active material layer, the anode active material layer and the electrolyte layer contains the sulfide solid electrolyte material according to claim 1 .

9. A method for producing the sulfide solid electrolyte material according to claim 1 ,
comprising steps of:
an ion conductive material synthesis step of synthesizing an amorphized ion conductive material by mechanical milling using a raw material composition containing a constituent component of the sulfide solid electrolyte material; and
a heating step of obtaining the sulfide solid electrolyte material by heating the amorphized ion conductive material.

Assignees

• Kato Yuki
• Ohtomo Takamasa
• Toyota Motor Co Ltd

Inventors

• Kato Yuki
• Ohtomo Takamasa

Classifications

• C01B17/22

  Alkali metal sulfides or polysulfides · CPC title

• H01M2300/0068

  inorganic · CPC title

• H01M10/0562 Primary

  Solid materials · CPC title

• C01B25/14

  Sulfur, selenium, or tellurium compounds of phosphorus · CPC title

• H01M10/052

  Li-accumulators · CPC title