LITHIUM SECONDARY BATTERY, MANUFACTURE OF PASTE FOR NEGATIVE ELECTRODE OF LITHIUM SECONDARY BATTERY, AND LITHIUM SECONDARY BATTERY HAVING PASTE FOR NEGATIVE ELECTRODE PREPARED BY ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To enhance binding capability and sticking capability and suppress the drop of discharge capacity and deterioration in load characteristic by including a thickening agent of an aqueous solution of carboxymethylcellulose having an ammonium salt as a functional group in a negative active material. SOLUTION: 50 pts.wt. flake graphite serving as a negative active material and an aqueous solution containing 1 pts.wt. carboxymethylcellulose having an ammonium salt as a functional group serving as a thickening agent are kneaded in a kneader 4, then the specified amount of each of the aqueous solution containing 1 pts.wt. carboxymethylcellulose having an ammonium salt as the functional group and a binder is added, and they are kneaded and dispersed to prepare negative electrode paste. The negative electrode past is applied to both surfaces of a negative current collector, dried, and a negative electrode plate is prepared. The peeling off or coming off of the negative active material from the current collector caused by high temperature storage or charge/discharge cycles is prevented, and drop in charge/discharge capacity or deterioration in charge/discharge characteristics is suppressed even under severe conditions.