Preparation and Electrochemical Property of AB3 Type LaMg2Ni9-x-y-zCoxMnyCuz Hydrogen Storage Alloys

AB(3) type LaMg2Ni9-x-y-zCoxMnyCuz (x=1.8, 2.1, 2.4, 2.7, 3.0; y=2.1, 2.4, 2.7, 3.0, 3.3; z=0.3, 0.6, 0.9, 1.2, 1.5) hydrogen storage alloys were synthesized by a coprecipitation-reduction-diffusion method according to the orthogonal experimental design. Their discharge capacity and cycle stability were studied and the structure was analyzed by XRD. The results indicate that the maximum discharge capacity of the series of alloys under multielement substitution is higher than the alloys under single element substitution, but the cycle stability decline slightly. Structure analyses show that the main phase of alloys is La4Co3. LaMg2Ni2.7Co2.1Mn2.7Cu1.5 alloy shows the best electrochemical properties in the series of hydrogen storage alloys.