Nonaqueous electrolyte secondary battery insulating porous layer

Patent metadata

Field	Value
Publication number	US-10637030-B2
Application number	US-201715593375-A
Country	US
Kind code	B2
Filing date	May 12, 2017
Priority date	Apr 14, 2017
Publication date	Apr 28, 2020
Grant date	Apr 28, 2020

Abstract

The present invention provides a nonaqueous electrolyte secondary battery insulating porous layer having an excellent charge resistance characteristic. The nonaqueous electrolyte secondary battery insulating porous layer has a fractal dimension of 2.42 to 2.60, the fractal dimension being calculated from a three-dimensional image showing a void part and a porous layer part on respective two gradation levels, the three-dimensional image being prepared by analyzing images of cross sections obtained by making observation at intervals of 20 nm in a thickness direction from a surface of the nonaqueous electrolyte secondary battery insulating porous layer by FIB-SEM measurement at a magnification of 6500 times.

First claim

The invention claimed is:

1. A laminated separator for a nonaqueous electrolyte secondary battery comprising:
a polyolefin porous film; and
an insulating porous layer comprising a thermoplastic resin,
the insulating porous layer having a fractal dimension of 2.42 to 2.60, the fractal dimension being calculated from a three-dimensional image showing a void part and a solid content part on respective two gradation levels, wherein the three-dimensional image is prepared by analyzing images of cross sections obtained by making observation at intervals of 20 nm in a thickness direction from a surface of the insulating porous layer using a FIB-SEM having a magnification of 6500 times,
the thermoplastic resin comprising: (i) an aromatic polymer selected from the group consisting of aromatic polyester, aromatic polycarbonate, and aromatic polyether, and (ii) a heat-resistant resin selected from the group consisting of aromatic polyamide, aromatic polyimide, and polybenzimidazole.

2. The laminated separator for a nonaqueous electrolyte secondary battery recited in claim 1 , wherein the aromatic polyamide is an aramid resin.

3. A nonaqueous electrolyte secondary battery comprising:
the laminated separator recited in claim 1 .

4. A nonaqueous electrolyte secondary battery comprising:
a cathode;
the laminated separator recited in claim 1 ; and
an anode,
the cathode, the laminated separator, and the anode being arranged in this order.

Assignees

• Sumitomo Chemical Co

Inventors

• Hara Syusaku
• Yoshimaru Chikae
• Suzuki Junji
• Hashiwaki Hiroki

Classifications

• H01M10/0585

  of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators · CPC title

• H01M2/1686 Primary

  Electricity · mapped topic

• H01M2/1646

  Electricity · mapped topic

• H01M2/1653

  Electricity · mapped topic

• H01M10/052 Primary

  Li-accumulators · CPC title