Solid electrolyte and method for manufacturing same

Patent metadata

Field	Value
Publication number	US-11901507-B2
Application number	US-201917251871-A
Country	US
Kind code	B2
Filing date	Sep 27, 2019
Priority date	Sep 28, 2018
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

The present invention relates to a polymer electrolyte and a method for manufacturing same. More specifically, a polymer electrolyte with improved ion conductivity can be produced by adding boron nitride to a solid electrolyte comprising polysiloxane.

First claim

The invention claimed is:

1. A solid electrolyte comprising:
a polysiloxane; and
boron nitride (BN),
wherein the boron nitride is a boron nitride surface-modified with polycyclic aromatic hydrocarbon.

2. The solid electrolyte according to claim 1 , wherein the solid electrolyte further comprises a lithium salt; and an organic solvent; wherein the polysiloxane is a polymer matrix and the boron nitride (BN) is a filler.

3. The solid electrolyte according to claim 1 , wherein the boron nitride is contained in an amount of 0.1 to 5% by weight based on the weight of the polysiloxane.

4. The solid electrolyte according claim 1 , wherein the polycyclic aromatic hydrocarbon is at least one selected from the group consisting of pyrene, perylene and benzoperylene.

5. The solid electrolyte according claim 1 , wherein the polycyclic aromatic hydrocarbon is one whose end is modified by a combination of polyethylene glycol (PEG).

6. The solid electrolyte according claim 1 , wherein the polycyclic aromatic hydrocarbon is contained in an amount of 4 to 10% by weight based on the total weight of the surface-modified boron nitride.

7. The solid electrolyte according to claim 1 , wherein the molecular weight of the polysiloxane is 800 to 1200 g/mol.

8. The solid electrolyte according to claim 2 , wherein the lithium salt is at least one selected from the group consisting of LiN(SO 2 CF 3 ) 2 (LiTFSI), LiSCN, LiN(CN) 2 , LiClO 4 , LiBF 4 , LiAsF 6 , LiPF 6 , LiCF 3 SO 3 , Li(CF 3 SO 2 ) 3 C, LiN(SO 2 CF 3 ) 2 , LiN(SO 2 CF 2 CF 3 ) 2 , LiSbF 6 , LiPF 3 (CF 2 CF 3 ) 3 , LiPF 3 (C 2 F 5 ) 3 , LiPF 3 (CF 3 ) 3 , and LiB(C 2 O 4 ) 2 .

9. The solid electrolyte according to claim 2 , wherein the organic solvent is at least one selected from the group consisting of methanol, acetone, 4-acetylmorpholine, 2-methylpyridine-1-oxide, 2-pyrrolidon, 1-(2-hydroxyethyl)-2-pyrrolidinone, propylene carbonate (PC), ethylene carbonate (EC), 2-oxepanone, butanone, 2-pentanone, methyl ethyl ketone (MEK) and methoxynonafluorobutane.

10. The solid electrolyte according to claim 2 , wherein the solid electrolyte further comprises a crosslinking agent comprising tetraallyl oxy ethane (TAOE).

11. A method for preparing a solid electrolyte comprising the steps of:
(S1) reacting a boron nitride with a polycyclic aromatic hydrocarbon to form a surface-modified boron nitride;
(S2) dissolving a polysiloxane, a crosslinking agent and a photo-initiator in an organic solvent to form a mixed solution;
(S3) adding the surface-modified boron nitride and a lithium salt to the mixed solution to form a slurry; and
(S4) casting the slurry onto a substrate and then curing the slurry.

12. The method for preparing the solid electrolyte according to claim 11 , wherein the initiator is at least one photo-initiator selected from the group consisting of 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxy-cyclohexyl phenyl ketone and 2,4,6-trimethylbenzoyldiphenyl-phosphineoxide.

13. A lithium secondary battery comprising the solid electrolyte of claim 1 .

14. The solid electrolyte according to claim 1 , wherein the polysiloxane is contained in an amount of 15 to 20% by weight based on the weight of the solid electrolyte.

15. The solid electrolyte according to claim 1 , wherein the solid electrolyte further comprises at least a polymer selected from the group consisting of allyl polyethylene glycol (APEG), polyethylene glycol (PEG), ethylene glycol (EG) and polyethylene glycol diacrylate (PEGDA).

16. The solid electrolyte according to claim 1 , wherein the boron nitride is contained in an amount of 0.1 to 3% by weight based on the weight of the polysiloxane.

17. The solid electrolyte according to claim 1 , wherein the boron nitride is contained in an amount of 0.1 to 1% by weight based on the weight of the polysiloxane.

18. The solid electrolyte according to claim 10 , wherein the crosslinking agent is contained in an amount of 5 to 10% by weight based on the weight of the solid electrolyte.

Assignees

• Lg Chemical Ltd
• Seoul Nat Univ R&Db Foundation
• Lg Energy Solution Ltd

Inventors

• Lee Jehoon
• Lee Jong-Chan
• Chae Jonghyun
• Kim Lucia
• Han Dong Hyeop
• Kim Na Kyung
• Jeong Daun
• Baik Ji-Hoon
• Chang Wansoo

Classifications

• H01M10/0565 Primary

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

• C01B35/146

  Compounds containing boron and nitrogen, e.g. borazoles (ammonium tetrafluoborates C01B35/063; ammonium borates C01B35/12) · CPC title

• C08L83/04

  Polysiloxanes · CPC title

• H01M10/058

  Construction or manufacture · CPC title

• H01M10/0525 Primary

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