Solid electrolyte material and method for producing the same

• US 10,396,395 B2
• Filed: 03/27/2018
• Issued: 08/27/2019
• Est. Priority Date: 03/31/2017
• Status: Active Grant

• Current Assignee: Tokyo Institute of Technology (National University Corporation Tokyo Institute of Technology), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Tokyo Institute of Technology (National University Corporation Tokyo Institute of Technology)
• Inventors: Kanno, Ryoji, Hori, Satoshi
• Primary Examiner(s): Slifka, Sarah A.
• Application Number:
  US15/937,422
• Publication Number:
  US 20180287204A1
• Time in Patent Office: 518 Days
• Field of Search: None
• CPC Class Codes: C01B 17/22 Alkali metal sulfides or polysulfides
• CPC Class Codes: C01P 2006/40 Electric properties
• 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 2300/0068 inorganic
• CPC Class Codes: H01M 2300/008 Halides
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

To improve the stability of an electrolyte, among the sulfide solid electrolytes of Li—P—S—X based (X is at least one of F, Cl, N and OH) containing no metal element other than lithium, a new solid electrolyte having a possibility to have high ion conductivity and a method for producing for obtaining the same easily. The disclosure achieves the object by providing a solid electrolyte material including a sulfide composition represented by a composition formula Li4−4y−x−zP4+1+y−xP5+xS4−zXz (Li4−4y−x−zP1+yS4−zXz), wherein 0.2≤x<1.0, 0≤z≤0.2, and 0≤y≤0.075, and X is at least one of F, Cl, N and OH, and the solid electrolyte material has a peak at a position of 2θ=17.8°±0.1°, 19.1°±0.1°, 21.7°±0.1°, 23.8°±0.1° and 30.85°±0.1° in X-ray diffraction measurement using a CuKα ray, and method for producing the same.

Claims

1. A solid electrolyte material comprising a sulfide composition represented by a composition formula Li₄₋

4y−

x−

zP⁴⁺<sub>1+y−

x</sub>P⁵⁺_xS<sub>4−

z</sub>X_z (Li<sub>4−

4y−

x−

z</sub>P<sub>1−

y</sub>S<sub>4−

z</sub>X_z), wherein 0.2≤

x<

1.0, 0≤

z≤

0.2, and 0≤

y≤

0.075, and

X is at least one of F, Cl, N and OH, and

the solid electrolyte material has a peak at a position of 2θ

=17.8°

±

0.1°

, 19.1°

±

0.1°

, 21.7°

±

0.1°

, 23.8°

±

0.1° and

30.85°

±

0.1°

in X-ray diffraction measurement using a CuKα

ray.

2. The solid electrolyte material according to claim 1, wherein ion conductivity is 0.4 mS/cm or more.

3. A method for producing the solid electrolyte material according to claim 1, the method comprising:

an ion conductive material synthesizing step of synthesizing an ion conductive material using a simple substance of P, a P compound, a S compound, and a Li compound as a raw material including a constituent of the sulfide composition; and

a heating step of obtaining the sulfide composition by heating the ion conductive material, and

at least one of the P compound, the S compound, and the Li compound includes at least one of a fluoride, a chloride, a nitride, and a hydroxide.

4. The method according to claim 3, wherein a heating temperature in the heating step is in a range of 230°

C. to 300°

C.