NICKEL-METAL HYDRIDE BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a nickel-metal hydride battery that has a long charge and discharge cycle life and a high charge efficiency in high temperature without coprecipitating cadmium or zinc in nickel hydroxide or without mixing the powder of cadmium oxide or cadmium hydroxide in the nickel hydroxide powder. SOLUTION: In the nickel-metal hydride battery which has a negative electrode made mainly of a hydrogen storing alloy, the positive electrode uses a mixture of an active substance made of mainly nickel hydroxide that is a powder of coprecipitation of cobalt hydroxide and an oxide or an hydroxide of zinc, and the content of coprecipitated cobalt hydroxide is 1 mol% or more and 20 mol% or less to the total of nickel hydroxide and cobalt hydroxide.