Polymer electrolyte composition including polymer having a structural unit represented by formula (1), electrolyte salt, and molten salt, and polymer secondary battery including the same

Patent metadata

Field	Value
Publication number	US-11296356-B2
Application number	US-201716606493-A
Country	US
Kind code	B2
Filing date	Apr 21, 2017
Priority date	Apr 21, 2017
Publication date	Apr 5, 2022
Grant date	Apr 5, 2022

Abstract

There is disclosed a polymer electrolyte composition that comprises a polymer having a structural unit represented by the following formula (1), at least one electrolyte salt selected from the group consisting of lithium salts, sodium salts, and magnesium salts, and a molten salt having a melting point of 250° C. or less:

wherein X − represents a counter anion.

First claim

The invention claimed is:

1. A polymer electrolyte composition comprising:
a polymer having a structural unit represented by the following formula (1):

wherein X represents a counter anion;
at least one electrolyte salt selected from the group consisting of lithium salts, sodium salts, magnesium salts, and calcium salts; and
a molten salt having a melting point of 250° C. or less,
wherein the molten salt is at least one selected from the group consisting of 1-ethyl-3-methylimidazolium-bis(trifluoromethanesulfonyl)imide, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium-bis(trifluoromethanesulfonyl)imide, and N-ethyl-N-methylpyrrolidinium-bis(trifluoromethanesulfonyl)imide, and
wherein a content of the molten salt is 30% by mass or more and less than 55% by mass based on the total amount of the composition.

2. The polymer electrolyte composition according to claim 1 , wherein the composition is formed in sheet form.

3. The polymer electrolyte composition according to claim 1 , wherein the electrolyte salt is a lithium salt.

4. The polymer electrolyte composition according to claim 1 , wherein an anion of the electrolyte salt is at least one selected from the group consisting of PF 6 −, BF 4 −, N(SO 2 ) 2 −, N(CF 3 SO 2 ) 2 −, B(C 2 O 4 ) 2 −, and ClO 4 −.

5. The polymer electrolyte composition according to claim 1 , wherein a content of the at least one electrolyte salt is 3% by mass or more and 30% by mass or less.

6. The polymer electrolyte composition according to claim 1 , wherein a content of the at least one electrolyte salt is 3% by mass or more and 25% by mass or less.

7. The polymer electrolyte composition according to claim 1 , wherein a content of the at least one electrolyte salt is 3% by mass or more and 20% by mass or less.

8. The polymer electrolyte composition according to claim 1 , wherein the content of the molten salt is 50% by mass or less based on the total amount of the composition.

9. The polymer electrolyte composition according to claim 1 , wherein a content of the polymer having the structural unit represented by the formula (1) is 30% by mass or more and 60% by mass or less based on the total amount of the composition.

10. The polymer electrolyte composition according to claim 1 , wherein the polymer having a structural unit represented by the following formula (1) is represented by the following formula (2):

wherein n is 300 to 4000, and Y− represents a counter anion.

11. The polymer electrolyte composition according to claim 10 , wherein n is 400 to 3500.

12. The polymer electrolyte composition according to claim 10 , wherein n is 500 to 3000.

13. A polymer secondary battery comprising:
a positive electrode;
a negative electrode; and
an electrolyte layer comprising the polymer electrolyte composition according to claim 1 provided between the positive electrode and the negative electrode.

Assignees

• Hitachi Chemical Co Ltd
• Showa Denko Materials Co Ltd

Inventors

• Ogawa Hideyuki
• Mikuni Hiroki
• SERA Yusuke

Classifications

• H01M10/0525 Primary

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

• H01M10/0567

  characterised by the additives · CPC title

• H01M2300/0082

  Organic polymers · CPC title

• C08K5/435

  Sulfonamides · CPC title

• H01M2300/0048

  Molten electrolytes used at high temperature · CPC title