Characterization of AB5-Type Metal Hydride Modified by Electroless Plating Nickel in Forming Process
Metal hydride (MH) alloy (MmNi3.81Mn0.41Al0.19Co0.76) is modified by the electroless nickel plating and used as the electroactive material of negative electrode in Ni/MH batteries. The effect of the concentrations of reductant (NaH2PO2×H2O), complex agent (Na3C6H5O7×2H2O), reaction time, and reaction temperature on the Ni loadings and the utilization of the modified MH are systematically studied. The experimental results reveal that the appropriate reaction time and temperature of electroless nickel plating are 30 min and 70 °C in this work. The loading amount of Ni-P on MH alloy is increased and decreased by increasing the concentration of reductant and complex agent, respectively. The steady utilization of unmodified MH alloy is 94.7±1.0 % in the forming process under the charge/discharge conditions of 0.2C charge to 160% SOC (state of charge) and 0.2C discharge to 0.95V. The utilization of MH alloys modified with conditions of [NaH2PO2×H2O] = 40 g L-1 and [Na3C6H5O7×2H2O] = 20 g L-1, T = 70 °C, t = 30 min and [MH] = 2g/100 ml, respectively, is improved to 101.9±0.3 %.
Shiquan Liu and Min Zuo
W. T. Wu and J. S. Do, "Characterization of AB5-Type Metal Hydride Modified by Electroless Plating Nickel in Forming Process", Advanced Materials Research, Vols. 306-307, pp. 139-142, 2011