| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method for obtaining a nickel electrode material which has good tap density and powder resistance, and in which discharge reserve can be sufficiently reduced. SOLUTION: The manufacturing method comprises a first process in which the positive electrode material, in which a covering layer made of a lower-grade cobalt compound is formed on the surface of a positive electrode active material particle made of nickel hydroxide solid solution, is oxidation treated using an oxidizer in the water or an alkaline water solution of 6 N or less at the temperature of 30-60 deg.C, and thereby, the lower-grade cobalt compound and a part of the nickel hydroxide are oxidized so that the average oxidation number of the nickel in the above positive electrode active material and the cobalt in the above covering layer becomes 2.05-2.30, and a second process in which the positive electrode after the above treatment is heat treated in the alkaline water solution of 10 N or more at the temperature of 110 deg.C or more. |
