Electrochemical characteristics of the Mg 1− xLa xNi ( x = 0, 0.05, 0.10) alloy synthesized by mechanical alloying

Abstract

The amorphous Mg 1− x La x Ni ( x=0, 0.05, 0.10) alloys (a-Mg 1− x La x Ni) were prepared by mechanical alloying (MA). Electrochemical properties of the alloy electrodes were characterized, the results showed that the specimens had large electrochemical discharge capacities at room temperature. The X-ray diffraction (XRD) results showed that the amorphous Mg 1− x La x Ni alloys decomposed into the crystalline Mg 2NiH 4 and Ni phases as the increase in electrochemical cycle number of the samples, which was the main reason for the discharge capacity losses of the electrodes. The cyclic life and differential thermal analysis (DTA) results showed that partially replacing Mg by appropriate amounts of La leads to an improvement of cyclic stability due to an increase of the thermal stability. In addition, the SEM analysis results showed that the replacement of Mg by La could prevent the MgNi alloy from a decrease in particle size. Over all, the amorphous Mg 0.95La 0.05Ni alloy showed the best electrochemical properties.