新型AB5储氢合金表面修饰方法及机理研究

探索了一种储氢合金表面修饰的新方法. 在HF和CuSO₄的混合溶液中对MH/Ni电池负极材料AB₅型储氢合金进行表面处理, 研究了HF含量对反应的影响；考察了铜颗粒沉积量对表面修饰的影响；测试了修饰后合金电极的电化学性能；应用交流阻抗分析了表面修饰对合金性能影响的作用机理. 电化学测试结果表明, 表面修饰后合金电极具有更好的高倍率放电能力和循环稳定性. EIS分析结果表明, 表面修饰使合金的活性增强, 导电性提高, 欧姆阻抗及电化学阻抗显著降低. 因此, 这种新型表面修饰方法可以有效地改善合金的电化学性能, 使之更好地满足电动车用动力型电源的要求.

A Novel Method of Surface Modification on AB5 Hydrogen Storage Alloy and Its Mechanism Analysis

A new method of surface modification on hydrogen storage alloy is investigated. The AB5 alloy of metal hydride electrode in MH/Ni battery is treated in the mixed solution of HF and CuSO4. The effects of HF content and copper particle deposition amount on surface modification reaction are studied. The performances of modified alloy are tested and electrochemical impedance spectroscopy (EIS) is applied to analyze the mechanism of treatment. The electrochemical testing results indicate that modified alloy has better rate capability and cycle sta-bility. And the EIS analysis shows that surface modification increases the activity and electrical conductivity of the alloy, and greatly decreases its ohmic and electrochemical impedance, which helps to improve electrochemical pro-perties of the battery. Therefore the modified alloy would well meet the requirement of power sources on electric vehicles.