Crystallographic and electrochemical characteristics of melt-spun Ti-Zr-Ni-La alloys

Ti-based icosahedral quasicrystalline phase (I-phase) exhibited excellent hydrogen storage property for special structure. Unfortunately, the application as the negative electrode material of the nickel-metal hydride batteries was limited due to the poor electrochemical kinetics. Meanwhile, rare-earth element was beneficial to the electrochemical properties of Ti, Zr-based alloy. In present work, Ti45Zr30Ni25Lax (x = 3, 5 and 7) alloys were prepared by melt-spinning. The effect of adding La on the electrochemical performance of melt-spun alloys was investigated in detail. The phase structure of the melt-spun alloys was analyzed by XRD and DSC. The results showed that the amorphous forming ability increased with increasing x value. The maximum discharge capacity decreased from 109 mAh g(-1) to 99 mAh g(-1) with increasing x value. High-rate dischargeability and cycling stability were improved by adding La, which may be resulted from the increase of amorphous phase in the alloy electrodes. (C) 2008 Elsevier B.V. All rights reserved.