应用电化学阻抗法测定了不同荷电状态 (SOC)和不同温度下MlNi3.75Co0 .65Mn0 .4 Al0 .2 金属氢化物电极中氢的扩散系数 .结果表明 :室温下该电极中氢的扩散系数随其荷电量的增大而减小 ,SOC为 5 0 %时氢的扩散系数随温度的升高而增大 ,相应的氢扩散活化能为 35kJ/mo
Electrochemical impedance spectroscopy was employed to determine the hydrogen diffusion coefficient in MlNi 3.75 Co 0.65 Mn 0.4 Al 0.2 metal hydride electrode with various states of charge(SOC) at room temperature and with 50% SOC at various temperatures. It was found that hydrogen diffusion coefficient in this electrode decreases with the increase in SOC at ambient temperature, and for the electrode with 50%SOC, hydrogen diffusion coefficient increases with the increase of temperature and the activation energy for hydrogen diffusion in it is 35 kJ/mol.
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