Patent ID: 9741990
Date: 2017-08-22
CPC Classifications: H01M,Y02E

Claim:
1. A nonaqueous electrolyte secondary battery laminated separator comprising a laminated porous film, comprising: (a) a porous film containing a polyolefin component in an amount of not less than 80% by volume with respect to a total volume of the porous film (a); and (b) a porous layer containing a resin, the porous film (a) having a thickness of not less than 5 μm and not more than 20 μm, the laminated porous film having a thickness of not less than 6 μm and not more than 25 μm, the laminated porous film having a Gurley value of not more than 250 sec/100 mL, a piercing strength of the laminated porous film and a piercing strength of the porous film (a) after removal of the porous layer from the laminated porous film satisfy Formulae (1) and (2) below, where S is the piercing strength of the laminated porous film, and Sp is the piercing strength of the porous film (a) after the removal of the porous layer from the laminated porous film.