摘要 |
To provide a secondary battery porous membrane that has superior heat resistance and flexibility and contributes to improvements in battery cycle characteristics. Also provided is a secondary battery having high cycle characteristics that uses this porous membrane. [Solution] This secondary battery porous membrane contains nonconductive particles and a binder. The binder is characterized by being formed from a polymer containing a nitrile group, a novel group, and a C 4+ straight-chain alkylene structural unit in the same molecule and the nitrile group content in the polymer constituting the binder being 1 - 25% by mass, with the iodine value of the polymer being 0 mg/100 mg - 30 mg/100 mg. |