Electrochemical Studies On The Mg-based Hydrogen Storage Alloy Electrodes

The effects of Pd substitution for Ni and Mg in Mg_0.9Ti_0.1Ni alloys on the alloys'cyclic stability, electrode kinetics properties and corrosion behaviors were studied in the thesis.As for the Pd substituted Mg_0.9Ti_0.1Ni_1-xPd_x (x = 0, 0.05, 0.10, 0.15) and Mg_0.9-xTi_0.1Pd_xNi (x = 0.04, 0.06, 0.08, 0.10) alloys, the substitution enhanced the alloys'cyclic stability effectively. It was found that the Mg_0.8Ti_0.1Pd_0.1Ni alloy possessed the longest cycle life (discharge capacity was larger than 200 mAh/g after 80 charge/discharge cycles) among these alloys. The substitution of Pd for Ni and Mg led the corrosion potentials more positive, decreased the corrosion currents of the alloys, and increased the resistances and the thickness of surface passive film. As for Mg_0.9-xTi_0.1Pd_xNi (x = 0.04～0.10) alloys, the extent of surface oxidation lessened with the increase of Pd content. The corrosion resistant performances of Pd substituted alloys were enhanced due to Pd substitution, which improved the cyclic stability markedly.Partial substitution of Pd for Ni effectively enhanced the electrode kinetics of the alloys. With the increase of Pd content from 0 to 0.05, the electrode kinetics performances of Mg_0.9Ti_0.1Ni_1-xPd_x (x = 0～0.15) alloys increased with Pd content. When the Pd content increased further, the electrode kinetics performances of the alloys decreased because of the increased alloy resistances. Owing to the similar reason, the electrode kinetics performances of Mg-side substituted...