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

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.