Method of preparing sulfide-based solid electrolyte, sulfide-based solid electrolyte prepared therefrom, and solid secondary battery including the sulfide electrolyte

Patent metadata

Field	Value
Publication number	US-11127974-B2
Application number	US-201916394015-A
Country	US
Kind code	B2
Filing date	Apr 25, 2019
Priority date	May 14, 2018
Publication date	Sep 21, 2021
Grant date	Sep 21, 2021

Abstract

A method of preparing a sulfide solid electrolyte, the method including: first contacting a starting materials including Li2S, P2S5, and LiI in a first solvent to provide a precursor; and second contacting the precursor with a second solvent to prepare the sulfide solid electrolyte, wherein the first solvent includes a C1-C3 alkyl group or a cyclic ether compound which is unsubstituted or substituted with a C1-C3 alkoxy group, and the second solvent includes a C1-C10 hydrocarbon substituted with a C1 to C6 alkoxy group.

First claim

What is claimed is:

1. A method of preparing a sulfide solid electrolyte, the method comprising:
first contacting a starting material comprising Li 2 S, P 2 S 5 , and LiI in a first solvent to provide a solvate; and
second contacting the solvate with a second solvent to prepare the sulfide solid electrolyte,
wherein the first solvent comprises a C 1 -C 3 alkyl group or a cyclic ether compound which is unsubstituted or substituted with a C 1 -C 3 alkoxy group,
the second solvent comprises a C 1 -C 10 hydrocarbon substituted with a C 1 to C 6 alkoxy group, and
the second contacting comprises heating the solvate in the second solvent at a temperature in a range from about 100° C. to about 180° C. for about 30 minutes to about 300 minutes to react the solvate.

2. The method of claim 1 , wherein the first solvent comprises an oxetane compound, a tetrahydrofuran compound, or a tetrahydropyran compound.

3. The method of claim 1 , wherein the first solvent is tetrahydrofuran.

4. The method of claim 1 , wherein the starting material further comprises GeS 2 , P 2 S 3 , P 2 O 5 , SiO 2 , B 2 S 3 , Al 2 S 3 , B 2 O 3 , or a combination thereof.

5. The method of claim 1 , wherein a concentration of the starting material in the first solvent is in a range of about 1 weight percent to about 10 weight percent, based on a total weight of the first solvent and the starting material.

6. The method of claim 1 , wherein a temperature of contacting the starting material in the first solvent to provide the solvate is in a range from about 30° C. to about 80° C.

7. The method of claim 1 , wherein second solvent comprises a C 1 -C 10 hydrocarbon.

8. The method of claim 1 , wherein the second solvent comprises
dimethyl ether, methyl ethyl ether, diethyl ether, methyl n-propyl ether, ethyl n-propyl ether, di-n-propyl ether, methyl iso-propyl ether, ethyl iso-propyl ether, di-iso-propyl ether, n-propyl iso-propyl ether, methyl n-butyl ether, ethyl n-butyl ether, n-propyl n-butyl ether, iso-propyl n-butyl ether, methyl sec-butyl ether, ethyl sec-butyl ether, n-propyl sec-butyl ether, iso-propyl sec-butyl ether, methyl iso-butyl ether, ethyl iso-butyl ether, n-propyl iso-butyl ether, iso-propyl iso-butyl ether, methyl tert-butyl ether, ethyl tert-butyl ether, n-propyl tert-butyl ether, iso-propyl tert-butyl ether, di-n-butyl ether, di-sec-butyl ether, di-iso-butyl ether, sec-butyl n-butyl ether, iso-butyl n-butyl ether, tert-butyl n-butyl ether, iso-butyl sec-butyl ether, tert-butyl sec-butyl ether, tert-butyl iso-butyl ether, or a combination thereof;
dimethoxy ethane, diethoxy ethane, methoxy ethoxy ethane, 1,3-dimethoxy propane, 1,3-diethoxy propane, 1-methoxy 3-ethoxy propane, 1,2-dimethoxy propane, 1,2-diethoxy propane, 1-methoxy 2-ethoxy propane, 1-ethoxy 2-methoxy propane, or a combination thereof;
cyclopropyl methyl ether, cyclopropyl ethyl ether, cyclobutyl methyl ether, cyclobutyl ethyl ether, cyclobutyl n-propyl ether, cyclobutyl iso-propyl ether, cyclopentyl methyl ether, cyclopentyl ethyl ether, cyclopentyl n-propyl ether, cyclopentyl iso-propyl ether, cyclopentyl n-butyl ether, cyclopentyl iso-butyl ether, cyclopentyl sec-butyl ether, cyclopentyl tert-butyl ether, cyclohexyl methyl ether, cyclohexyl ethyl ether, cyclohexyl n-propyl ether, cyclohexyl iso-propyl ether, cyclohexyl n-butyl ether, cyclohexyl iso-butyl ether, cyclohexyl sec-butyl ether, or cyclohexyl tert-butyl ether; or
a combination thereof.

9. The method of claim 1 , wherein the second solvent comprises dimethoxyethane, diethoxyethane, diethyl ether, di-iso-propyl ether, cyclopentylmethyl ether, or a combination thereof.

10. The method of claim 1 , wherein the heating of the solvate is performed at a pressure which is less than atmospheric pressure.

11. The method of claim 1 , wherein the first contacting and the second contacting are each performed in an inert gas atmosphere.

12. The method of claim 1 , further comprising cleaning or drying the sulfide solid electrolyte obtained after the second process.

13. The method of claim 1 ,
wherein the starting material further comprises LiBr, and
wherein the sulfide solid electrolyte is represented by Formula (1):
(1− x )LiI. x LiBr.2Li 3 PS 4   (1)

wherein, in Formula 1, x is from greater than 0 to 1.

14. The method of claim 1 , wherein the sulfide solid electrolyte exhibits peaks at angles of 19.9±0.5°, 23.5±0.5°, and 29.3±0.5° two-theta when analyzed by an X-ray diffraction using a Cu—Kα radiation, and
wherein a ratio of an intensity of the peak at 19.9±0.5° two-theta to an intensity of a peak at 17.0±0.5° two-theta is less than 0.50.

15. The method of claim 1 , wherein the sulfide solid electrolyte has an ionic conductivity in a range from about 1×10 −5 Siemens per centimeter to about 1×10 −2 Siemens per centimeter at a temperature of 25° C.

16. The method of claim 1 , wherein the sulfide solid electrolyte has an activation energy in a range from about 30 kilojoules per mole to about 40 kilojoules per mole.

17. The method of claim 1 , wherein the second contacting comprises heating the solvate in the second solvent at the temperature in the range from about 100° C. to about 180° C. for about 30 minutes to about 300 minutes to react the solvate with a halogen substance.

18. A sulfide solid electrolyte prepared by the method of claim 1 .

19. A solid secondary battery comprising:
a positive electrode comprising a positive active material,
a negative electrode comprising a negative active material, and
a solid electrolyte layer disposed between the positive electrode and the negative electrode, wherein the solid electrolyte layer comprises a sulfide solid electrolyte prepared according to claim 1 .

Assignees

• Samsung Electronics Co Ltd

Inventors

• Ito Seitaro
• Tsujimura Tomoyuki
• Aihara Yuichi
• Machida Nobuya

Classifications

• H01M10/052

  Li-accumulators · CPC title

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M10/0525

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

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• H01M10/058

  Construction or manufacture · CPC title