Highly heat resistant and flame retardant separator, and electrochemical cell

Patent metadata

Field	Value
Publication number	US-2018294458-A1
Application number	US-201615570673-A
Country	US
Kind code	A1
Filing date	Apr 22, 2016
Priority date	Apr 29, 2015
Publication date	Oct 11, 2018
Grant date	—

Abstract

The present invention relates to: a separator comprising a porous substrate, and a heat resistant porous layer on one or both surfaces of the porous substrate, wherein the heat resistant porous layer comprises a cross-linked product of a cross-linkable functional group-containing phosphate-based or phosphonate-based monomer, oligomer, or polymer; an electrochemical cell comprising the same; or a method for preparing the separator.

First claim

1 . A separator comprising
a porous substrate and a heat resistant porous layer on one or both surfaces of the porous substrate, wherein the heat resistant porous layer comprises a cross-linked product of a cross-linkable functional group-containing phosphate-based or phosphonate-based monomer, oligomer, or polymer.

2 . The separator of claim 1 , wherein the cross-linkable functional group-containing phosphate-based or phosphonate-based monomer, oligomer, or polymer is a compound of Chemical Formula 1 or Chemical Formula 2.

wherein, in Chemical Formula 1 or 2,
R 1 and R 4 are independently selected from a substituted or unsubstituted, C 1-18 alkylene, C 2-6 alkenylene, C 3-12 cycloalkylene, and C 6-30 aromatic containing group,
R 2 , R 3 , and R 5 are independently selected from a substituted or unsubstituted, hydrogen, C 1-18 alkyl, C 2-6 alkenyl, C 3-12 cycloalkyl, C 6-30 aromatic containing group, and halogen atom,
n is an integer ranging from 1 to 1000, and
m is 0 or 1.

3 . The separator of claim 2 , wherein in Chemical Formula 1 or Chemical Formula 2, R 1 and R 4 are independently a substituted or unsubstituted C 6-30 aromatic containing group, R 2 is a substituted or unsubstituted C 6-30 aromatic containing group or halogen atom, and R 3 is a substituted or unsubstituted, hydrogen, or C 1-18 alkyl, or halogen atom.

4 . The separator of claim 2 , wherein in Chemical Formula 2, the cross-linkable functional group is introduced into at least one of each substituent of R 4 and R 5 .

5 . The separator of claim 1 , wherein the cross-linked product is a cross-linked product of the cross-linkable functional group-containing phosphate-based or phosphonate-based monomer, oligomer, or polymer with a multi-functional (meth)acrylate.

6 . The separator of claim 5 , wherein the multi-functional (meth)acrylate is (meth)acrylate including two or more functional groups selected from a vinyl group, an epoxy group, and a hydroxyl group.

7 . The separator of claim 1 , wherein the porous substrate is a polyolefin-based porous substrate.

8 . The separator of claim 1 , wherein the heat resistant porous layer further includes an inorganic particle.

9 . The separator of claim 8 , wherein the inorganic particle comprises one or more selected from the group consisting of Al 2 O 3 , SiO 2 , B 2 O 3 , Ga 2 O 3 , TiO 2 , and SnO 2 .

10 . The separator of claim 1 , wherein the heat resistant porous layer further comprises a polymer resin in addition to the cross-linked product.

11 . A separator comprising
a porous substrate; and a heat resistant porous layer formed on one or both surfaces of the porous substrate, wherein an electrolyte solution shrinkages of the separator at a width direction and a length direction at 150° C. and 60 minutes are each less than or equal to 45%, and a flame retardancy is greater than or equal to V2 according to UL94 VB flame-retardance regulations.

12 . The separator of claim 11 , wherein air permeability of the separator is less than or equal to 400 sec/100 cc.

13 . A method of preparing a separator, comprising
preparing a heat resistant porous layer composition comprising a cross-linkable functional group-containing phosphate-based or phosphonate-based monomer, oligomer, or polymer, a polymerization initiator, and a solvent, and coating the heat resistant porous layer composition on one or both surfaces of the porous substrate and performing a cross-linking reaction to form a heat resistant porous layer.

14 . The method of claim 13 , wherein the cross-linkable functional group-containing phosphate-based or phosphonate-based monomer, oligomer, or polymer is a compound of Chemical Formula 1 or 2.

wherein, in Chemical Formula 1 or 2,
R 1 and R 4 are independently selected from a substituted or unsubstituted, C 1-18 alkylene, C 2-6 alkenylene, C 3-12 cycloalkylene, and C 6-30 aromatic containing group,
R 2 , R 3 , and R 5 are independently selected from a substituted or unsubstituted, hydrogen, C 1-18 alkyl, C 2-6 alkenyl, C 3-12 cycloalkyl, C 6-30 aromatic containing group, and halogen atom,
n is an integer ranging from 1 to 1000, and
m is 0 or 1.

15 . The method of claim 13 , wherein the heat resistant porous layer composition further comprises a multi-functional (meth)acrylate.

16 . The method of claim 15 , wherein the multi-functional (meth)acrylate is a (meth)acrylate having two or more functional groups selected from a vinyl group, an epoxy group, and a hydroxyl group.

17 . The method of claim 13 , wherein the cross-linking reaction is thermal curing, photo-curing, or high humidity and high temperature curing.

18 . An electrochemical cell comprising a positive electrode, a negative electrode, a separator and an electrolyte, wherein the separator comprises the separator of claim 1 .

19 . The electrochemical cell of claim 18 , wherein the electrochemical cell is a lithium rechargeable cell.

20 . An electrochemical cell comprising a positive electrode, a negative electrode, a separator and an electrolyte, wherein the separator comprises the separator of claim 12 .

Assignees

• Samsung Sdi Co Ltd

Inventors

• Ko Chang Hong
• Seo Dong Wan
• Jin Mok Yun

Classifications

• H01M10/4235 Primary

  Safety or regulating additives or arrangements in electrodes, separators or electrolyte (H01M10/4242 takes precedence) · 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

• H01M50/449

  having a layered structure · CPC title

• H01M2/145

  Electricity · mapped topic