| abstract |
An object of the present invention is to provide a binder composition capable of forming a functional layer capable of suppressing swelling after a cycle of a secondary battery and enhancing the charge carrier solubility of a secondary battery at a low temperature. The binder composition of the present invention contains a first polymer, a second polymer, and a solvent, wherein the first polymer comprises a block region composed of an aromatic vinyl monomer unit and an aliphatic conjugated diene monomer unit and/or an aliphatic conjugated diene monomer number. It is a block copolymer having a block region composed of a digested product unit, and the second polymer is a random copolymer containing 1,3-pentadiene units and/or 1,3-pentadiene hydride units. |