充放电制度对La-Mg-Ni合金电极性能的影响

Effects of charge-discharge system on the performance of the La-Mg-Ni alloy electrodes

采用不同电流进行充放电测试,研究充放电制度对La0.75Mg0.25Ni3.5Cox(x=0、0.2、0.4和0.6)合金电极电化学性能的影响。随着电流的增加,合金的最大放电容量降低。在600 mA/g时合金的循环寿命长于100 mA/g时。X射线光电子能谱(XPS)的结果表明,在KOH电解液中,电极失效的主要原因是合金中La和Mg元素的腐蚀和氧化。

The effects of charge-discharge system on the electrochemical performance of La0.75 Mg0.25 Ni3.5 Cox （x=0,0.2, 0.4 and 0.6） alloy electrodes were studied by the charge-discharge tests with different currents. The maximum discharge capacities of the alloys decreased with the increasing of the current. The cycle lives of the alloys at 600 mA/g were longer than those at 100 mA/g. The result of X-ray photoelectron spectroscopy （XPS） showed that the main reason of the electrode degradation in KOH electrolyte was the corrosion and oxidation of La and Mg elements in the alloy.