| 摘要 |
PURPOSE:To produce a hydrogen storage alloy for a battery capable of satisfying large current discharging properties in addition to three characteristics of high electrode capacity, long service life characteristics and good rising characteristics, to provide a method for producing the same and to produce a nickel hydrogen battery. CONSTITUTION:This hydrogen storage alloy for a battery is constituted of an allay having a compsn. expressed by the general formula A Nia Mnb Alc Cod Me (where A denotes at least one kind of element selected from rare earth elements including Y (yttrium), M denotes at least one kind selected from W, Ta, Mo, Nb, In, Ga, Sn, Zn, Cr, V, Ti, Zr and Hf and 3.5<=a<=5, 0.1<=b<=1, 0<=c<=1, 0.1<=d<=1, 0<e<=0.6 and 4.5<=a+b+c+d+e<=6 are satisfied), at least a part of this alloy has a columnar crystalline structure, and the average breadth of the columnar crystals is regulated to 5 to 30mum. Moreover, the area ratio of the columnar structure in which the ratio of the breadth and length (aspect ratio) of the columnar crystals is regulated to (1:2) or above is regulated to <=50%. |
