The electrochemical performance of an AB 2-type hydrogen storage alloy (Ti 0.35Zr 0.65Ni 1.2V 0.6Mn 0.2) modified by electroless Ni-P and Ni coatings in acid hypophosphite and hydrazine baths, respectively, is investigated. It is found that electrochemical properties of the modified electrodes (i.e., high-rate dischargeability, cycle life, ability to retain discharge capacity after overdischarge) and the electrocatalytic activity for the hydrogen electrode reaction are improved by this surface modification. The high-rate dischargeability of the alloy coated with Ni from the hydrazine bath is better than that coated with NiP from the acid hypophosphite bath, but the activation cycles required for the Ni-coated electrode to reach maximum capacity are four times as many as those required by the electrode coated with NiP. A duplex nickel coating method has therefore been developed. The duplex nickel-coated alloy (i.e., alloy first coated with NiP and then coated with Ni) retains the characteristics of better high-rate dischargeability but requires fewer activation cycles in comparison with the Ni-coated alloy.