Structure and electrochemical characteristics of Ti0.25-xZrxV0.35Cr0.1Ni0.3(x=0.05-0.15) alloys

The structure and electrochemical properties of the Ti0.25-xZrxV0.35Cr0.1Ni0.3(x=0.05-0.15) alloy electrodes have been investigated. These alloys mainly consist of a V-based solid solution with BCC structure and a C14 Laves phase with hexagonal structure as determined by X-ray diffraction analysis. Scanning electron micrographs show that these alloys form dendritic crystal. The discharge capacities of the alloys increase with increasing temperature from 303 to 333 K, and then decrease while the temperature is above 333 K. The cycle life, the rate capability and the electrochemical impedance spectra are also investigated. The Laves phase as electrocatalyst increases the fresh surface during charging-discharging process, improving the electrochemical performance of these alloy electrodes. (c) 2005 Elsevier Ltd. All rights reserved.