| R-Mg-Ni based AB3-type hydrogen storage alloy is considered to be one of the optimal substitute to the commercial AB5-type hydrogen storage alloys. But the shortages of AB3-type hydrogen storage alloys electrode, such as the lower cycle-stability, still limited the development. So we improve the synthetically electrochemical properties of hydrogen storage alloy by the study of the surface treatment techniques.In this paper, we treated the R–Mg–Ni based AB3–type hydrogen storage alloy with the method of F-duplex surface treatment and acidifications copperize duplex treatment. And by the electrochemical property, electrochemical kinetically, SEM and EDS testing results, we study the effects of surface morphologies in taking the electrochemical and kinetically properties of electrode alloy.After F-duplex surface treatment, the ratio of the initial discharge capacity to the maximum discharge capacity of La0.88Mg0.12Ni2.95Mn0.10Co0.55Al0.10 hydrogen storage alloy improved more than 21.0%. At 720 mA/g to 1800 mA/g discharge current density, the HRD improved more than 10.0% after surface treatment, and the cycle stability improved too, but with the continual circulation the increase speed lower and lower. Through the acidifications copperize duplex treatment on La0.88Mg0.12Ni2.95Mn0.10Co0.55Al0.10 hydrogen storage alloy, it is indicated that the optimization condition is the temperature 298 K, the concentration of etching treatment solution 0.02 mol/L, the coating treatment solution 0.004 g/L, the coating time 3 min. Under the optimization condition, the initial activation characteristics, high rate discharge ability and cycle life are all improved in different extent. The C1st/Cmax improved from 61.1% to 75.0%, the HRD increased about 7.0% and 12.8% respectively at the discharge current density of 0.2 C and 5 C, and the S100 improved from 91% to 93%.
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