Abstract: The present invention is to provide a cathode active material for an alkaline battery with a lamellar crystal structure including nickel oxyhydroxide. The cathode active material has a diffraction peak at a position that ranges from 8.4 degrees to 10.4 degrees in diffraction angle 2? by X-ray diffraction using CuK?-rays. In addition, the present invention provides an alkaline battery having a cathode having a cathode active material, an anode having an anode active material, and an alkaline water solution as an electrolytic solution. Furthermore, the present invention provides a manufacturing method for a cathode active material for an alkaline battery with a lamellar crystal structure including nickel oxyhydroxide. The manufacturing method has an oxidation process for manufacturing the cathode active material by oxidizing a starting material made from ?-type nickel hydroxide with a lamellar crystal structure in an airstream including alkaline water solution or alkali.

Abstract: An alkaline storage battery 1 has: a cathode 2 containing ?-type nickel hydroxide and/or ?-type nickel oxyhydroxide as a cathode active material; an anode 3 containing an anode active material; and an alkaline aqueous solution as an electrolytic solution 4. The alkaline storage battery 1 is configured to restrain at least part of a crystal structure of the cathode active material from changing due to charging or discharging and to restrain the cathode active material from exhibiting a new diffraction peak at a position that ranges from 8.4 degrees to 10.4 degrees in X-ray diffraction angle 2? by X-ray diffraction using CuK?-rays. It is preferable that an anion-exchange membrane layer 25 should be provided on a surface of the cathode 2.