	US 12,191,439 B2
	Nonaqueous electrolyte secondary battery porous layer
Kensaku Horie, Niihama (JP); and Yuichiro Azuma, Osaka (JP)
Assigned to SUMITOMO CHEMICAL COMPANY, LIMITED, Tokyo (JP)
Filed by Sumitomo Chemical Company, Limited, Tokyo (JP)
Filed on Apr. 15, 2020, as Appl. No. 16/848,885.
Claims priority of application No. 2019-078119 (JP), filed on Apr. 16, 2019.
Prior Publication US 2020/0335757 A1, Oct. 22, 2020
Int. Cl. H01M 10/0525 (2010.01); H01M 50/417 (2021.01); H01M 50/423 (2021.01); H01M 50/451 (2021.01); H01M 50/489 (2021.01)

CPC H01M 10/0525 (2013.01) [H01M 50/417 (2021.01); H01M 50/423 (2021.01); H01M 50/451 (2021.01); H01M 50/489 (2021.01)]

9 Claims

1. A nonaqueous electrolyte secondary battery laminated separator comprising:

a polyolefin porous film; and

a nonaqueous electrolyte secondary battery porous layer formed on a least one surface of the polyolefin porous film,

the nonaqueous electrolyte secondary battery porous layer comprising:

a resin; and

a filler,

the nonaqueous electrolyte secondary battery porous layer having a thickness of less than 8.0 μm,

the nonaqueous electrolyte secondary battery porous layer having a surface which is not adjacent to the polyolefin porous film, said surface have a surface roughness (Ra) of 0.01 μm to not more than 0.098 μm.