An alkaline storage battery 1 has: a cathode 2 containing ²-type nickel hydroxide and/or ²-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.
