BINDER COMPOSITION FOR LITHIUM-ION SECONDARY CELL POSITIVE ELECTRODE SLURRY COMPOSITION FOR LITHIUM-ION SECONDARY CELL POSITIVE ELECTRODE LITHIUM-ION SECONDARY CELL POSITIVE ELECTRODE AND LITHIUM-ION SECONDARY CELL

摘要

The present invention provides a binder composition for a positive electrode of a lithium ion secondary battery capable of suppressing expansion of a positive electrode. The binder composition for a positive electrode of a lithium ion secondary battery of the present invention comprises a copolymer comprising a nitrile group-containing monomer unit and a conjugated diene monomer unit and a solvent, wherein the copolymer has an electrolyte swelling degree of not less than 200 mass% and not more than 700 mass% and a binder composition is the binder layer obtained by film formation of the storage modulus, at least 1 × 10 ⁴ Pa 1 × 10 ⁹ Pa or less.