Electrochemical Performance Improvement of AB5-type Metal Hydride Electrode by Adding KF in KOH Electrolyte

摘要:

研究了在6 mol/L KOH 电解液中添加不同浓度KF 对商用AB5-型贮氢合金的电化学性能的影响，研究发现合金的循环性能和循环后期的高倍率性能提高，通过XRD, SEM, SEI等分析表明，在电解液中添加KF生成的LaF3能显著提高合金耐腐蚀的能力，同时阻止合金电极在循环过程中析氢过电位降低，提高合金的动力学性能

Abstract:

The influence of the added KF concentration in the 6 mol/L KOH electrolyte on the electrochemical performances of the commercial AB5-type hydrogen storage alloy was investigated. The cycle life and high-rate performance of the commercial AB5-type hydrogen storage alloy can be improved by adding KF to the electrolyte. The analyses of XRD, SEM and SEI show that the formation of LaF3 in KF-added electrode can obviously decrease the corrosion of the metal hydride electrode compared with that of the KF-free electrode which prevents the dropping of the hydrogen evolution reaction voltage of the electrode and results in the improvement of electrochemical dynamics of the electrode