Abstract We have investigated the Zr(V x Ni 1− x ) 2 alloy series in the range of 0 ⩽ x ⩽ 0.4 and observed very pronounced absorption and desorption properties in Zr(V 0.25Ni 0.75) 2. We have shown previously that Zr(V 0.25Ni 0.75) 2 has a high reversible capacity of 364 mA h g −1 (C/30 rate) and a good electrochemical cycle stability (8%/100 cycles capacity loss, C/3 rate). However, large-scale production of this alloy seems to be difficult, and annealing deteriorates the high capacity and the good kinetics as well. In this study we have analyzed the microstructure of the alloy and the thermodynamics of hydride formation of the alloy electrodes. Two different phases were observed, Zr 7Ni 10 and Zr(V 0.33Ni 0.67) 2.3; however, both of them are, as single phase alloys, not quite as good as their combination in Zr(V 0.25Ni 0.75) 2.