BINDER COMPOSITION FOR ELECTRODES OF LITHIUM ION SECONDARY BATTERIES AND USE THEREOF

A binder composition comprising (1) an organic liquid material, (2) polymer particles (A) insoluble in the organic liquid material, and (3) a polymer (B) soluble in the organic liquid material, said polymer (B) comprising structural units derived from an ethylenically unsaturated carboxylic acid ester represented by the following formula (I): wherein R is hydrogen, methyl or carboxyl group, R is hydrogen, methyl or carboxymethyl group, and R is substituted or unsubstituted alkyl group. By using this binder composition, an electrode having improved surface smoothness can be produced. A lithium ion secondary battery provided with the electrode has good charge-discharge characteristics.