Preparation And Electrochemical Property Of Composite Electrode Of Lamg2ni2.7co2.1mn2.7cu1.5 Coated With Tio2

LaMg2Ni2.7CO2.1Mn2.7Cu1.5 hydrogen storage alloy was synthesized by co-precipitation and reduction diffusion, and TiO2 powder was prepared by a hydrothermal method. Then the alloy was coated with TiO2 powder to prepare composite electrode. The structures of the hydrogen storage alloy and TiO2 powder were characterized by X-ray diffraction. The electrochemical performances of the composite electrode were tested by battery tester under two different conditions. In one condition, the electrode was kept in a dark box. In the other condition, the electrode was kept under radiation of a ultraviolet lamp. The results show that in the dark box the activation performance and maximum discharge capacity of composite electrode are not as good as that of original alloy electrode that is not coated with TiO2, but the cyclic stability becomes better. In light condition, the electrochemical performances of the composite electrode, including activation performance, maximum discharge capacity and cyclic stability, become better than that of original alloy electrode. The maximum discharge capacity of the composite electrode (coated with 20% TiO2) increases by 25 mAh.g(-1) compared with original alloy electrode. It is illustrated that TiO2 by surface coating is effective to improve electrochemical performances of the LaMg2Ni2.7Co2.1Mn2.7Cu1.5 hydrogen storage alloy.