Electrochemical Property Of La-Mg-Ni Prepared Via Mechanical Milling Catalyzed With LiBr

Hydrogen storage and transport are the most important process of the Hydrogen large-scale application. Therefore, it’s great significance to study the hydrogen storage materials. In the most of hydrogen storage materials, La2Mg17hydrogen storage material is received widespread attention because of its high hydrogen storage capacity, high discharge capacity and fast activation. The disadvantage of hydrogen absorption and desorption kinetics of poor performance limit the application of this alloy in electrochemistry. La2Mg17/Ni with LiBr composites hydrogen storage materials were prepared by ball milling process with catalyst LiBr in this paper. It had been investigated the effects of LiBr on the electrochemical performance of composites.La2Mg17/Ni+xwt.%LiBr (x=0,3,5,7,10,20,30) composites were ball milled60h (5h ball milling for LiBr). The microstructure of the ball-milled composites had been analyzed. The effects of LiBr contents on the electrochemical performance of composites had been investigated. The effects of LiBr ball milling times on the electrochemical performance of composites with5wt.%and10wt.%LiBr had been studied on the basis of the result of effects of LiBr contents. Ultimately, the optimal milling process parameters for preparing the composites was determined.The results revealed that ball-milling process with LiBr could refine La2Mg17/Ni alloy particles and promote the composites to form uniform and homogenous amorphous. The composites with5wt.%LiBr got550.38mAh/g discharge capacity. It’s3.11times of the composites without LiBr. It showed that LiBr improved the electrochemical properties of the composites. The composites ball-milled5h for LiBr with5wt.%LiBr got the best performance of electrochemical kinetics with the limiting current density of468.533mA/cm2. It’s1.27times and1.89times of the composites ball-milled1h and12h LiBr respectively.The best milling process for composite materials is that LiBr content is5wt.%, LiBr milling time is5h and the total milling time for composites is60h.