METHOD FOR MANUFACTURING LITHIUM SECONDARY BATTERY

摘要

PURPOSE: A method for manufacturing a rechargeable lithium secondary battery is provided to improve the battery safety, when the inner temperature of the battery is elevated by overcharge or nailpenetration, etc., by using a crystalline binder polymer which can increase the electric resistance and aging the battery at high temperature. CONSTITUTION: The method for manufacturing a lithium secondary battery comprises: (a) a step of preparing a positive electrode by dispersing, into a solvent, (i) a positive electrode material(1), (ii) a main binder and (iii) 0.1-10wt% of at least one electric resistant binder(2) having a particle diameter of 15-40 micrometer, selected from a group consisting of polyethylene, polypropylene, chlorinated polyethylene having a chlorination degree of 0 to 50%, polybutylene, chlorinated polypropylene having a chlorination degree of 0 to 50% and polyethylene derivatives to give a slurry, coating the slurry to an electric-current collector for a positive electrode, and drying and compressing the electric-current collector coated with the slurry; (b) a step of preparing a negative electrode by dispersing, into a solvent, (i) a negative electrode material and (ii) a main binder to give a slurry, coating the slurry to an electric-current collector for a negative electrode, and drying and compressing the electric-current collector coated with the slurry; (c) assembling a battery by laminating the positive electrode, a separator and the negative electrode in this order, and injecting a non-aqueous electrolyte; and (d) aging the assembled battery at a high temperature of 30-130 deg.C.