Laminated porous film and non-aqueous electrolyte secondary cell

Patent metadata

Field	Value
Publication number	US-10290849-B2
Application number	US-201515119232-A
Country	US
Kind code	B2
Filing date	Feb 6, 2015
Priority date	Feb 18, 2014
Publication date	May 14, 2019
Grant date	May 14, 2019

Abstract

A laminated porous film, including: a porous layer containing a polyolefin; and a porous layer containing a heat-resistant material and provided on at least one surface of the porous layer containing the polyolefin, the laminated porous film satisfying Formula (I) below,

0.1136×α+0.0819×β+3.8034≥4.40  (I),
where α is a value of a film resistance (Ω·cm 2 ) of the laminated porous film, and β is a value of a volume (cc/m 2 ) of the heat-resistant material contained per 1 m 2 of the porous layer containing the heat-resistant material.

First claim

The invention claimed is:

1. A laminated porous film, comprising:
a porous layer containing a polyolefin; and
a porous layer containing a heat-resistant material and provided on one or both surfaces of the porous layer containing the polyolefin,
the laminated porous film satisfying Formula (I) below,
0.1136×α+0.0819×β+3.8034≥4.40  (I),

where
α is a value of a film resistance (Ω·cm 2 ) of the laminated porous film, and
β is a value of a volume (cc/m 2 ) of the heat-resistant material contained per 1 m 2 of the porous layer containing the heat-resistant material,
wherein the value α is within a range of 0.25 Ω·cm 2 to 2.00 Ω·cm 2 ,
wherein the value β is within a range of 5 cc/m 2 to 10 cc/m 2 ,
wherein the porous layer containing the polyolefin has a thickness within a range of 5 μm to 30 μm,
wherein the porous layer containing the heat-resistant material has a thickness within a range of 1 μm to 20 μm,
wherein the laminated porous film has an air permeability within a range of 50 sec/100 cc to 2000 sec/100 cc,
wherein the heat resistant-material is contained at a proportion of more than 50% by volume based on an entire solid content of the porous layer,
wherein the heat-resistant material includes a binder and filler, the binder being a water-soluble polymer,
wherein the filler has a proportion of 20% by weight to 99% by weight with respect to the combined weight of the binder and the filler, and
wherein the filler is made of alumina.

2. The laminated porous film according to claim 1 ,
wherein
the laminated porous film satisfies Formula (I-2) below,
4.90≥0.1136×α+0.0819×β+3.8034≥4.40  (I-2).

3. A nonaqueous electrolyte secondary battery, comprising
a laminated porous film according to claim 1 .

4. The laminated porous film according to claim 1 , wherein the water-soluble polymer is a carboxy alkyl cellulose, an alkyl cellulose, a hydroxyalkyl cellulose, starch, polyvinyl alcohol, or sodium alginate.

Assignees

• Sumitomo Chemical Co

Inventors

• Kurakane Kosuke
• Murakami Chikara
• Okugawa Takahiro
• Suzuki Yutaka
• Ozeki Tomoaki

Classifications

• H01M10/0525 Primary

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

• H01M50/457

  comprising three or more layers · CPC title

• H01M50/451

  comprising layers of only organic material and layers containing inorganic material · CPC title

• H01M50/417 Primary

  Polyolefins · CPC title

• H01M50/491

  Porosity · CPC title