Electrochemical characteristics and synergetic effect of Ti0.10Zr0.15V0.35Cr0.10Ni0.30-10 wt.%LaNi5 hydrogen storage composite electrode

Abstract

In order to improve performance of Ti-V-based solid solution alloy, electrochemical characteristics and synergetic effect of Ti0.10Zr0.15V0.35Cr0.10Ni0.30−10 wt.%LaNi5 hydrogen storage composite electrode prepared by two-step arc-melting were investigated systematically. X-ray diffractometry (XRD) and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) showed that the main phase of composite alloy was composed of V-based solid solution phase with a BCC structure and C14 Laves phase with hexagonal structure, while secondary phase also existed in the composite alloy. The results showed that electrochemical characteristics of the composite alloy electrode were significantly improved. It was suggested that synergetic effect appeared in the maximum discharge capacity of the composite alloy, synergetic effect of the discharge capacity appeared in the activation process, in the composite process, in the cyclic process, in the discharge process at low/high temperature and at different current densities, and synergetic effect existed in the charge-transfer resistance and in the exchange current density, which seemed to be related to formation of the secondary phase.