| 摘要 |
PROBLEM TO BE SOLVED: To provide excellent initial characteristic and life and improve the high-rate discharge characteristic by arranging a main phase not surface- reformed, a layer richer in Ni than the main phase, and a layer covered with P successively from the inside to the outside. SOLUTION: A main phase not surface-reformed of a hydrogen storage alloy powder is represented by the general formula (La)x R1-x (Ni)a Mb (wherein R represents at least one selected from rare earth metals other than La, M represents at least one selected from the group consisting of Mn, Al, Co, Ti, Fe, and Zr, and (x), (a) and (b) are positive numbers, respectively, wherein (x) is 0.2-1, (b) is 0<b<=0.2, and a+b is 4.0-6.0). This main phase is covered with a Ni-rich layer 25 nm-100 nm thick formed by removing a soluble material with an acidic solution, and then subjected to condensed phosphoric acid treatment to form a layer 1 nm-50 nm thick, the outermost surface of which is covered with P, is formed. |
