Abstract: AB_₅-type hydrogen storage alloy La_0.65Ce_0.28Pr_0.02Nd_0.05Ni_3.8Co_0.7Mn_0.3Al_0.2 was prepared by twin-roll process, and the microstructure, capacity and cyclic
stability of the alloy were characterized by SEM, XRD and constant current charge and discharge. The alloy has a uniform nano-scale crystallite size
of about 40nm. Its discharge capacity is 336mAh/g at 0.2C rate (64mA/g), and 312mAh/g at 2C rate (640mA/g) and retains 80% of the initial capacity after
400 cycles. The influence of La content on electrochemical capacity and cyclic stability of the alloy was also studied. It is found that discharge capacity
of the alloy increases with the increase of La content when La less than 60wt% and keeps unchanging from 60% to 80%. However, cyclic stability of
the alloy decreases with the increase of La content.

Key words: twin-roll process, hydrogen storage alloy, capacity, cyclic stability, crystallite size