Polymer electrolyte for secondary battery comprising lithium salt and polymer and lithium secondary battery including the same

Patent metadata

Field	Value
Publication number	US-11539073-B2
Application number	US-201816633115-A
Country	US
Kind code	B2
Filing date	Aug 31, 2018
Priority date	Sep 12, 2017
Publication date	Dec 27, 2022
Grant date	Dec 27, 2022

Abstract

The present invention relates to a polymer electrolyte for a secondary battery and a lithium secondary battery including the same, and to a polymer electrolyte for a secondary battery, which includes unit A derived from a poly(ethylene oxide)-based polymer, and a lithium secondary battery including the same.

First claim

The invention claimed is:

1. A polymer electrolyte for a secondary battery, the polymer electrolyte comprising:
a lithium salt; and
unit A derived from polymer (a) represented by Formula 1:

wherein, in Formula 1,
R 1 , R 2 , and R 3 are each independently hydrogen or —CH 2 —CH═CH 2 ,
at least one of R 1 , R 2 , and R 3 is —CH 2 —CH═CH 2 ,
each of a, b, and c is the number of repeating units, and
a, b, and c are each independently an integer of any one of 1 to 10,000, and
wherein a weight ratio of the lithium salt to the unit A derived from the polymer (a) represented by Formula 1 is in a range of 1:1 to 1:9.

2. The polymer electrolyte of claim 1 , wherein the polymer (a) represented by Formula 1 comprises at least one selected from the group consisting of polymers represented by Formulae 1a to 1c:

wherein, in Formula 1a,
each of a1, b1, and c1 is the number of repeating units, and
a1, b1, and c1 are each independently an integer of any one of 1 to 10,000,

wherein, in Formula 1b,
each of a2, b2, and c2 is the number of repeating units, and
a2, b2, and c2 are each independently an integer of any one of 1 to 10,000, and

wherein, in Formula 1c,
each of a3, b3, and c3 is the number of repeating units, and
a3, b3, and c3 are each independently an integer of any one of 1 to 10,000.

3. The polymer electrolyte of claim 1 , wherein a weight ratio of the lithium salt to the unit A derived from the polymer (a) represented by Formula 1 is in a range of 1:1 to 1:6.

4. The polymer electrolyte of claim 1 , further comprising an oxygen (O 2 ) inhibitor.

5. A composition comprising
a lithium salt;
an organic solvent; and
a polymer (a) represented by Formula 1:

wherein, in Formula 1,
R 1 , R 2 , and R 3 are each independently hydrogen or —CH 2 —CH═CH 2 ,
at least one of R 1 , R 2 , and R 3 is —CH 2 —CH═CH 2 ,
each of a, b, and c is the number of repeating units, and
a, b, and c are each independently an integer of any one of 1 to 10,000, and
wherein a weight ratio of the lithium salt to the polymer (a) represented by Formula 1 is in a range of 1:1 to 1:9.

6. The composition of claim 5 , wherein a weight ratio of the lithium salt to the polymer (a) represented by Formula 1 is in a range of 1:1 to 1:6.

7. The composition of claim 5 , further comprising a polymerization initiator.

8. The composition of claim 5 , further comprising an oxygen (02) inhibitor.

9. A method of preparing a secondary battery, the method comprising:
coating the composition of claim 5 on at least one surface of a positive electrode, a negative electrode, and a separator; and
forming a polymer electrolyte for a secondary battery by thermal curing the composition.

10. A method of preparing a secondary battery, the method comprising:
coating the composition of claim 5 on a base;
forming a polymer electrolyte for a secondary battery by thermally curing the composition;
separating the polymer electrolyte from the base; and
disposing the separated polymer electrolyte on at least one surface of a negative electrode, a positive electrode, and a separator.

11. A lithium secondary battery comprising the polymer electrolyte of claim 1 .

12. The polymer electrolyte of claim 1 , wherein the oxygen inhibitor includes tris(2,2,2-trifluoroethyl)phosphite.

13. The polymer electrolyte of claim 1 , wherein an amount the oxygen inhibitor is 0.1 wt % to 10 wt % based on a total weight of solid content in the polymer electrolyte.

14. The composition of claim 5 , wherein the oxygen inhibitor includes tris(2,2,2-trifluoroethyl)phosphite.

15. The composition of claim 5 , wherein an amount the oxygen inhibitor is 0.1 wt % to 10 wt % based on a total weight of solid content in the composition.

16. The polymer electrolyte of claim 1 , wherein a weight ratio of the lithium salt to the unit A derived from the polymer (a) represented by Formula 1 is in a range of 1:2 to 1:4.

Assignees

• Lg Chemical Ltd
• Lg Energy Solution Ltd

Inventors

• Park Sol Ji
• Ahn Kyoung Ho
• Lee Chul Haeng
• Han Jun Hyeok

Classifications

• H01M10/0525 Primary

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

• H01M2300/0082

  Organic polymers · CPC title

• C08F16/18

  Acyclic compounds · CPC title

• Y02P70/50

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

• H01M10/0565 Primary

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