Secondary battery porous membrane, slurry for secondary battery porous membrane, and secondary battery

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 C4+ 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.

主权项

1. A secondary battery porous membrane comprising a non-conductive particle and a binder; wherein
said binder comprises a polymer including a nitrile group, a hydrophilic group and a linear alkylene structural unit having carbon atoms of 4 or more in a same molecule, a content ratio of said nitrile group in the polymer constituting said binder is 1 to 25 wt % and an iodine value of said polymer is 0 mg/100 mg or more and 30 mg/100 mg or less, and a content ratio of said hydrophilic group in the polymer constituting said binder is 1 to 6 wt %.