| abstract |
PROBLEM TO BE SOLVED: To provide a nickel-hydrogen storage battery in which a positive electrode active material is improved to improve its capacity density and to improve the characteristics of a positive electrode. SOLUTION: A nickel-hydrogen storage battery comprising a positive electrode, a negative electrode, an alkaline electrolyte, and a separator, wherein nickel hydroxide, which is a main active material of the positive electrode, contains 8 atomic% of Mn with respect to the metal nickel. , Na 4 atomic%, Ca 4 Atomic% solid solution, and in the charged state, the X-ray diffraction with CuKα as a source has a diffraction angle 2θ of 16 ° (16 °). 1) A hexagonal or tetragonal system having a plane diffraction peak and a regular array having a NaCl-type structure. |