Resin composition for manufacturing separator, preparation method therefor, and battery comprising same

Patent metadata

Field	Value
Publication number	US-11322796-B2
Application number	US-201916762274-A
Country	US
Kind code	B2
Filing date	Apr 25, 2019
Priority date	May 25, 2018
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

A resin composition for fabricating a separator which is easy to control viscosity, a method of preparing the same, and a battery including the same, are disclosed.

First claim

The invention claimed is:

1. A resin composition for fabricating a separator comprising:
a sulfonated polymer;
an amide group-containing organic solvent; and
water,
wherein the amide group-containing organic solvent is present in an amount of 20 parts to 30 parts by weight relative to 100 parts by weight of the sulfonated polymer.

2. The resin composition for fabricating the separator of claim 1 , wherein the amide group-containing organic solvent comprises at least one selected from the group consisting of dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone, N-methylformamide, N-vinylacetamide, N-vinylpyrrolidone, formamide, and 2-pyrrolidone.

3. The resin composition for fabricating the separator of claim 2 , wherein the amide group-containing organic solvent comprises at least one selected from the group consisting of dimethylacetamide and dimethylformamide.

4. The resin composition for fabricating the separator of claim 1 , wherein the sulfonated polymer comprises a perfluorosulfonic acid-based polymer.

5. The resin composition for fabricating the separator of claim 1 , wherein a molar ratio of a sulfonic acid group of the sulfonated polymer to the amide group of the amide group-containing organic solvent is 1:1.13 to 1:1.7.

6. The resin composition for fabricating the separator of claim 1 , wherein a viscosity of the resin composition for fabricating the separator is 100 cps to 3000 cps.

7. The resin composition for fabricating the separator of claim 1 , wherein the resin composition for fabricating the separator comprises 20% by weight to 30% by weight of the sulfonated polymer, 4% by weight to 9% by weight of the amide group-containing organic solvent, and 61% by weight to 76% by weight of water based on a total weight of the resin composition.

8. A method for preparing a resin composition for fabricating a separator, comprising steps of:
(a) preparing a mixture of a sulfonated polymer and water; and
(b) adding, to the mixture of (a), 20 parts to 30 parts by weight of an amide group-containing organic solvent relative to 100 parts by weight of the sulfonated polymer.

9. The method for preparing the resin composition for fabricating the separator of claim 8 , wherein a desired viscosity is obtained by checking a change of the viscosity with time while the resin composition prepared in step (b) is stored for 1 day to 17 days.

10. A method for fabricating a separator comprising steps of:
(a) shaping a sheet-shaped separator using the resin composition for fabricating the separator of claim 1 ; and
(b) after the shaping in step (a), heating to 70° C. to 220° C. to remove the amide group-containing organic solvent.

11. The method for fabricating the separator of claim 10 , wherein the step of shaping the sheet-shaped separator is performed by a roll to roll process.

12. A battery comprising:
a negative electrode;
a positive electrode; and
a separator disposed between the negative electrode and the positive electrode,
wherein the separator is fabricated from the resin composition for fabricating the separator of claim 1 .

13. The battery of claim 12 , wherein the battery is a vanadium redox flow battery.

Assignees

• Lg Chemical Ltd

Inventors

• KIM Sungyeon
• Noh Tae Geun

Classifications

• C08J5/18 Primary

  Manufacture of films or sheets · CPC title

• H01M50/417

  Polyolefins · CPC title

• H01M50/489

  Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties · CPC title

• C08J3/096

  Nitrogen containing compounds · CPC title

• H01M50/403

  Manufacturing processes of separators, membranes or diaphragms · CPC title