Gelled electrolyte and preparation method thereof

Patent metadata

Field	Value
Publication number	US-11996519-B2
Application number	US-201917274185-A
Country	US
Kind code	B2
Filing date	Sep 9, 2019
Priority date	Sep 10, 2018
Publication date	May 28, 2024
Grant date	May 28, 2024

Abstract

A gel composition, in particular a gelled electrolyte, comprising: i) fumed alumina particles, wherein the mean primary particle size of the particle is from 5 to 50 nm and the BET specific surface area is from 40 to 400 m 2 /g; ii) at least two organic solvents; and iii) a lithium salt; wherein the amount of the alumina particles is 0.2-10% by weight based on the total weight of the gel composition. A method to prepare a gelled electrolyte, a Li-ion battery, a Li-ion battery and a device are also provided.

First claim

The invention claimed is:

1. A gelled electrolyte composition, comprising:
i) fumed alumina particles, wherein the mean primary particle size of the particles is from 5 to 50 nm and the BET specific surface area is from 40 to 400 m 2 /g;
ii) at least two organic solvents; and
iii) a lithium salt;
wherein the amount of the fumed alumina particles is 0.2-10% by weight based on the total weight of the gelled electrolyte composition, and wherein the fumed alumina particles are not surface-modified.

2. The gelled electrolyte composition of claim 1 , wherein the organic solvents are selected from the group consisting of: ethylene carbonate (EC); dimethyl carbonate (DMC); propylene carbonate; methylethyl carbonate; and diethyl carbonate.

3. The gelled electrolyte composition of claim 1 , wherein the mean primary particle size of the fumed alumina particles is from 10 to 30 nm.

4. The gelled electrolyte composition of claim 1 , wherein the BET specific surface area of the fumed alumina particles is from 50 to 150 m 2 /g.

5. The gelled electrolyte composition of claim 1 , wherein the amount of the fumed alumina particles is 0.5-8% by weight, based on the total weight of the gelled electrolyte composition.

6. The gelled electrolyte composition of claim 2 , wherein the lithium salt is selected from the group consisting of: lithium hexafluorophosphate; lithium bis 2-(trifluoromethyl-sulfonyl)imide; LiClO 4 ; LiBF 4 ; Li 2 SiF 6 ; and LiN (SO 2 CF 2 CF 3 ).

7. The gelled electrolyte composition of claim 6 , wherein the BET specific surface area of the fumed alumina particles is from 50 to 150 m 2 /g and the mean primary particle size of the fumed alumina particles is from 10 to 30 nm.

8. The gelled electrolyte composition of claim 7 , wherein the amount of the fumed alumina particles is 0.5-8% by weight based on the total weight of the gelled electrolyte composition.

9. A method of preparing a gelled electrolyte, comprising the following steps:
a) mixing at least two organic solvents and a lithium salt to obtain a liquid mixture; and
b) dispersing fumed alumina particles in the liquid mixture to obtain the gelled electrolyte;
wherein:
the mean primary particle size of the fumed alumina particles is from 5 to 50 nm and the BET specific surface area of the fumed alumina particles is from 40 to 400 m 2 /g;
the amount of the alumina particles is 0.2-10% by weight, based on the total weight of the gelled electrolyte; and
the alumina particles are not surface-modified.

10. The method of claim 9 , wherein the electrochemical rate performance of the gelled electrolyte or a Li-ion battery comprising the gelled electrolyte is improved relative to electrolyte in which the alumina particles that are not surface-modified are replaced with either hydrophobically modified fumed alumina particles or unmodified silica particles and wherein the alumina particles are the sole gellation component.

11. The method of claim 10 , wherein the fumed alumina particles are dried before mixing in step a).

12. The method of claim 9 , wherein the mean primary particle size of the fumed alumina particles is from 10 to 30 nm.

13. The method of claim 9 , wherein the BET specific surface area of the fumed alumina particles is from 50 to 150 m 2 /g.

14. The method of claim 9 , wherein the amount of the fumed alumina particles is 0.5-8% by weight based on the total weight of the gel composition.

15. The method of claim 11 , wherein the mean primary particle size of the fumed alumina particles is from 10 to 30 nm.

16. The method of claim 15 , wherein the BET specific surface area of the fumed alumina particles is from 50 to 150 m 2 /g.

17. The method of claim 16 , wherein the amount of the fumed alumina particles is 0.5-8% by weight based on the total weight of the gelled electrolyte.

18. A Li-ion battery, comprising the gelled electrolyte composition of claim 1 .

19. The Li-ion battery of claim 18 , wherein the mean primary particle size of the fumed alumina particles in the gelled electrolyte is from 10 to 30 nm.

20. The Li-ion battery of claim 19 , wherein the BET specific surface area of the fumed alumina particles in the gelled electrolyte is from 50 to 150 m 2 /g and wherein the amount of the fumed alumina particles in the gelled electrolyte is 0.5-8% by weight based on the total weight of the gelled electrolyte.

Assignees

• Evonik Operations Gmbh

Inventors

• Su Shasha
• Jiang Jinhua
• Feng Jing
• Wang Dong
• Huang Yuan-Chang
• Yang Jun
• Lei Bin
• Xu Zhixin

Classifications

• H01M10/0565 Primary

  Polymeric materials, e.g. gel-type or solid-type · CPC title

• H01M10/0525

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

• H01M2300/0037

  Mixture of solvents · CPC title

• H01M2300/0085

  Immobilising or gelification of electrolyte · CPC title

• H01M10/052 Primary

  Li-accumulators · CPC title