Slurry for secondary battery porous membrane, a secondary battery porous membrane, an electrode for secondary battery, a separator for secondary battery and a secondary battery

Patent metadata

Field	Value
Publication number	US-9660238-B2
Application number	US-201113878095-A
Country	US
Kind code	B2
Filing date	Oct 7, 2011
Priority date	Oct 7, 2010
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

A secondary battery porous membrane, manufactured by a slurry for secondary battery porous membrane, which is superior in coating priority and dispersibility of non-conductive organic particles, which improves cycle characteristic of the obtained secondary battery, which has high flexibility and can prevent powder falls, and which has less content of moisture amount; and non-conductive organic particles, which can be suitably used as a secondary battery porous membrane and has less content of metallic foreign particles. The slurry for secondary battery porous membrane comprises; a binder including a polymerized unit of vinyl monomer having a hydrophilic acid group, a non-conductive organic particle having a functional group, cross-linkable with the hydrophilic acid group and a solvent.

First claim

The invention claimed is:

1. A slurry for a secondary battery porous membrane comprising:
a binder including a polymerized unit of vinyl monomer having a hydrophilic acid group;
a non-conductive organic particle having a functional group, which is cross-linkable with the hydrophilic acid group; and
a solvent,
wherein:
the non-conductive organic particle includes a polymerized unit of divinylbenzene and a polymerized unit of ethylvinyl benzene, and
a content of the functional group which is cross-linkable with the hydrophilic acid group, with respect to the non-conductive organic particle, is 0.068 to 0.240 mmol/g.

2. The slurry for secondary battery porous membrane as set forth in claim 1 , wherein the binder further includes a polymerized unit of (meth)acrylic ester monomer and a polymerized unit of α, β-unsaturated nitrile monomer;
and in a total polymerized unit,
a content ratio of the polymerized unit of vinyl monomer having a hydrophilic acid group is 0.1 to 10 wt %,
a content ratio of the polymerized unit of (meth)acrylic ester monomer is 50 to 98 wt %, and
a content ratio of the polymerized unit of α, β-unsaturated nitrile monomer is 1.0 to 50 wt %.

3. The slurry for secondary battery porous membrane as set forth in claim 1 , wherein the hydrophilic acid group is a sulfonic acid group or a phosphoric acid group.

4. The slurry for secondary battery porous membrane as set forth in claim 1 , wherein the functional group, which is cross-linkable with the hydrophilic acid group, is an epoxy group or an alkoxysilane group.

5. The slurry for secondary battery porous membrane as set forth in claim 1 , wherein:
an average particle diameter of the non-conductive organic particle is 0.1 to 2.0 μm, and a temperature in which a weight reduction ratio of the non-conductive organic particle reaches 10 wt % is 250° C. or more, when heated from 30 ° C. at a temperature rising rate of 10° C/min. by a thermobalance under a nitrogen atmosphere.

6. A secondary battery porous membrane obtained by forming a membrane with the slurry for secondary battery porous membrane as set forth in claim 1 and drying the same.

7. A secondary battery porous membrane comprising:
a binder, including a polymerized unit of vinyl monomer having a hydrophilic acid group; and
a non-conductive organic particle having a functional group, which is cross-linkable with the hydrophilic acid group;
wherein:
a cross-linkage structure is formed between the binder and the non-conductive organic particle,
the non-conductive organic particle includes a polymerized unit of divinylbenzene and a pglymerized unit of ethylvinyl benzene, and
a content of the functional group which is cross-linkable with the hydrophilic acid group, with respect to the non-conductive organic particle, is 0.068 to 0.240 mmol/g.

8. An electrode for secondary battery comprising
a current collector,
an electrode active material layer, including an electrode active material and a binder for electrode, which is adhered to the current collector, and
the secondary battery porous membrane as set forth in claim 6 , stacked on a surface of the electrode active material layer.

9. A separator for secondary battery comprising an organic separator and the secondary battery porous membrane as set forth in claim 6 , stacked on the organic separator.

10. A secondary battery comprising a positive electrode, a negative electrode, an organic separator and an electrolytic solution, wherein the secondary battery porous membrane as set forth in claim 6 is stacked on one of the positive electrode, the negative electrode or the organic separator.

11. The slurry for secondary battery porous membrane as set forth in claim 2 , wherein the hydrophilic acid group is a sulfonic acid group or a phosphoric acid group.

12. The slurry for secondary battery porous membrane as set forth in claim 2 , wherein the functional group, which is cross-linkable with the hydrophilic acid group, is an epoxy group or an alkoxysilane group.

13. The slurry for secondary battery porous membrane as set forth in claim 3 , wherein the functional group, which is cross-linkable with the hydrophilic acid group, is an epoxy group or an alkoxysilane group.

14. The slurry for secondary battery porous membrane as set forth in claim 2 , wherein:
an average particle diameter of the non-conductive organic particle is 0.1 to 2.0 μm, and a temperature in which a weight reduction ratio of the non-conductive organic particle reaches 10 wt % is 250° C. or more, when heated from 30° C. at a temperature rising rate of 10° C/min. by a thermobalance under a nitrogen atmosphere.

15. The slurry for secondary battery porous membrane as set forth in claim 3 , wherein:
an average particle diameter of the non-conductive organic particle is 0.1 to 2.0 μm, and a temperature in which a weight reduction ratio of the non-conductive organic particle reaches 10 wt % is 250 ° C. or more, when heated from 30 ° C. at a temperature rising rate of 10° C/min. by a thermobalance under a nitrogen atmosphere.

16. The slurry for secondary battery porous membrane as set forth in claim 4 , wherein:
an average particle diameter of the non-conductive organic particle is 0.1 to 2.0 μm, and a temperature in which a weight reduction ratio of the non-conductive organic particle reaches 10 wt % is 250 ° C. or more, when heated from 30 ° C. at a temperature rising rate of 10° C/min. by a thermobalance under a nitrogen atmosphere.

17. The slurry for a secondary battery porous membrane as set forth in claim 1 , wherein a content ratio of the polymerized unit of divinylbenzene with respect to a total weight of a monomer in the non-conductive organic particle is 20 wt % to 80 wt %.

18. The slurry for a secondary battery porous membrane as set forth in claim 1 , wherein a content ratio of the polymerized unit of ethylvinyl benzene with respect to a total weight of a monomer in the non-conductive organic particle is 3.2 wt % to 48 wt %.

19. The secondary battery porous membrane as set forth in claim 7 , wherein a content ratio of the polymerized unit of ethylvinyl benzene with respect to a total weight of a monomer in the non-conductive organic particle is 3.2 wt % to 48 wt %.

Assignees

• Matsumura Taku
• Kaneda Takuya
• Wakizaka Yasuhiro
• Zeon Corp

Inventors

• Matsumura Taku
• Kaneda Takuya
• Wakizaka Yasuhiro

Classifications

• H01M4/13 Primary

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M50/423

  Polyamide resins · CPC title

• H01M50/417

  Polyolefins · CPC title

• H01M50/491

  Porosity · 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