Lithium ion secondary battery electrode binder, slurry obtained using these electrode binders, electrode obtained using these slurries, and lithium ion secondary battery obtained using these electrodes

摘要

An object of the present invention is to provide: a binder for a lithium ion secondary battery electrode, which is water-dispersible type and has favorable adhesion between active materials and between the active material and current collectors, along with charge-discharge high-temperature cycle characteristics; a slurry using the binder; an electrode using the slurry; and a lithium ion secondary battery using the electrode. The present invention relates to a binder composition for a lithium ion secondary battery electrode, which is obtained by emulsion polymerization of an ethylenically unsaturated monomer in the presence of a surfactant, the ethylenically unsaturated monomer containing, as essential constituents, 15 to 70 mass % of styrene with respect to the total mass of ethylenically unsaturated monomers, an ethylenically unsaturated carboxylic acid ester, an ethylenically unsaturated carboxylic acid and an internal cross-linking agent.