| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly safe separator for a battery to improve liquid suction speed of a porous film, especially a polyolefin porous film made porous by a dry method.SOLUTION: The separator for the battery has: the porous film; and a nonwoven fabric laminated on at least one face of this porous film. The porous film has a thermoplastic polymer layer to have the melting point of 150°C or more. As for the nonwoven fabric, basis weight is 5 g/mor more and 30 g/mor less, the maximum fiber diameter of a constituting fiber as the body is within a range of 3 μm or more and 20 μm or less, and when the average film thickness of the porous film is a μm and the average film thickness of the nonwoven fabric is b μm, a value of a film thickness ratio a/b is 1 or more and 10 or less. |
