Alkaline storage battery and method of manufacturing the same

摘要

An alkaline storage battery includes a positive electrode active material containing nickel hydroxide as a main component. A part of the surface of the nickel hydroxide is unevenly covered with a cobalt compound having an average oxidation number of larger than +2 and containing alkaline cations. Since only a part of the surface of the nickel hydroxide is covered with the cobalt compound, the nickel hydroxide not covered with the cobalt compound is brought into direct contact with the electrolyte, thus improving the high rate discharging characteristic. Since a part of the surface of the nickel hydroxide is covered with the high-order cobalt compound containing alkaline cations, the high-order cobalt compound with high conductivity produces a highly conductive network within the positive electrode so that the rate of using the active material is improved. In this configuration, the alkaline storage battery with high capacity and excellent high rate discharging characteristic can be provided by using a nickel hydroxide active material which permits nickel hydroxide to be brought into direct contact with an electrolyte regardless with high order cobalt oxide on the surface of nickel hydroxide.