| 摘要 |
PROBLEM TO BE SOLVED: To improve the shelf life and handling property by treating a pulverized hydrogen storage alloy with alkali and then treating it with a solution containing a compound having a specified structure. SOLUTION: A pulverized hydrogen storage alloy is treated with an alkali such as lithium hydroxide. It is then dipped in a solution containing a conjugate unsaturated compound having 5 or more conjugate π bondings in one molecule and a molecular weight of 100 or more, specifically a benzene derivative such as phenol followed by stirring and then dried. As the hydrogen storage alloy, MmNi5 is preferably used from the viewpoint of increasing the cycle life (Mm is a mesh metal formed of a mixture of rare earth elements such as La, Ce, Pr and Nd). The thus-formed powder is used, whereby a nickel-hydrogen secondary battery excellent in initial activity can be provided. The alkali concentration is 1.0-10.0 N, and the treatment temperature ranges from ordinary temperature to 130 deg.C. |
