Laminate, non-aqueous electrolyte secondary battery separator including the laminate, and non-aqueous electrolyte secondary battery including the laminate

Patent metadata

Field	Value
Publication number	US-9917289-B2
Application number	US-201514771149-A
Country	US
Kind code	B2
Filing date	Jul 21, 2015
Priority date	Oct 10, 2014
Publication date	Mar 13, 2018
Grant date	Mar 13, 2018

Abstract

Provided is a laminate which is capable of ensuring a high level of safety by preventing an internal short circuit due to, for example, breakage of a non-aqueous electrolyte secondary battery while maintaining various performance capabilities of the non-aqueous electrolyte secondary battery. A laminate ( 10 ) includes: a porous film containing polyolefin as a main component; and a porous layer containing fine particles; the porous layer being laminated to at least one side of the porous film, in an electrical conduction test by nail penetration in which test a difference between (a) a test force of the laminate ( 10 ) which is brought into electrical conduction and (b) a test force of the laminate ( 10 ) in which a dielectric breakdown occurs, the difference being obtained by subtracting the test force (b) from the test force (a), is measured by use of a nail ( 2 ) of N50 specified in JIS A 5508 and under a condition in which the nail ( 2 ) descends at a descending speed of 50 μm/min, the difference being not less than 5 N and not more than 50 N.

First claim

The invention claimed is:

1. A laminate comprising:
a porous film containing polyolefin as a main component; and
a porous layer containing inorganic fine particles which have cleavability;
the porous layer being laminated to at least one side of the porous film,
the porous layer containing, per one side thereof, a porous layer component in a component volume weight per unit area of 2 cm 3 /m 2 to 8 cm 3 /m 2 ,
the porous layer having, per one side thereof, a thickness of 0.5 μm to 15 μm, and the porous film has a thickness of 5 μm to 30 μm, and
in an electrical conduction test by nail penetration in which test a difference between (a) a test force of the laminate which is brought into electrical conduction and (b) a test force of the laminate in which a dielectric breakdown occurs, the difference being obtained by subtracting the test force (b) from the test force (a), is measured by use of a nail of N50 specified in JIS A 5508 and under a condition in which the nail descends at a descending speed of 50 μm/min, the difference being not less than 5 N and not more than 50 N.

2. The laminate as set forth in claim 1 , wherein the porous film has a porosity of 30% by volume to 60% by volume.

3. The laminate as set forth in claim 1 , wherein the porous layer further contains a binder resin, and the fine particles are in point contact with the binder resin.

4. The laminate as set forth in claim 1 , wherein the porous film has a weight per unit area of 4 g/m 2 to 20 g/m 2.

5. The laminate as set forth in claim 1 , wherein the porous layer has, per one side thereof, a weight per unit area of 1 g/m 2 to 20 g/m 2.

6. A non-aqueous electrolyte secondary battery separator including a laminate recited in claim 1 .

7. A non-aqueous electrolyte secondary battery including a laminate recited in claim 1 .

Assignees

• Sumitomo Chemical Co

Inventors

• Yoshimaru Chikae
• Kurakane Kosuke
• Murakami Chikara

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

• H01M50/423

  Polyamide resins · CPC title

• H01M50/42

  Acrylic resins · CPC title