The electrode alloys (Mg1-xZrx)(2)Ni (x=0, 0.1) were prepared by mechanical alloying (MA). Mg in the alloy was partially substituted with Zr in order to improve the electrochemical characteristics of the Mg2Ni-type alloy. The microstructures and the electrochemical characteristics of the experimental alloys were measured systemically. The effects of substituting Mg with Zr as well as the relevant MA technique on the microstructures and electrochemical performances of the alloys were investigated in detail. The results show that the substitution of Zr is favourable for the formation of an amorphous phase. The electrochemical measurement indicated that the substitution of Zr can dramatically enhance the discharge capacity and cycle stability, and it markedly improves the discharge voltage characteristic of the alloys. For a fixed alloy, the electrochemical performances, including the cycle stability, the discharge voltage characteristic and discharge capacity, of the alloys were significantly improved with the increase of the ball-milling duration. (c) 2007 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.