Negative electrode active material for nickel-hydrogen storage battery, negative electrode for nickel-hydrogen storage battery, and nickel-hydrogen storage battery

摘要

PROBLEM TO BE SOLVED: To realize a negative electrode active substance for a nickel - hydrogen storage battery at low cost which hardly corrodes in an electrolyte solution and has a high energy density. SOLUTION: The negative electrode active substance for the nickel - hydrogen storage battery contains a hydrogen storage alloy as represented in the formula below and a cerium system material: Ln1-aMaNixAlyMnzCou, where, Ln denotes a mixture at least containing 50 wt.% of La. M denotes an element as chosen from a group of elements consisting of Mg, Ca, Sr, and Ba. Further, a, x, y, z, and u satisfy the following conditions. 0.01=a=0.1 3.5x=4.5 0.1=y+z=1.0 0.1=u=0.6 5.1=x+y+z+u=5.5.