La_(1.3)CaMg_(0.7)Ni_9 hydrogen storage alloy

The structure of La_(1.3)CaMg_(0.7)Ni_9 hydrogen storage alloy was analyzed by XRD. The gas hydrogen storage characteristics and electrochemical properties of alloy were investigated. The results show that the prepared alloy is composed of LaNi_3 with PuNi_3 structure as matrix phase and LaNi_5 and LaNi_(2.28) as secondary phases. At 1.6MPa H_2 pressure and 300K the hydrogen storage capacity of alloy reaches to 1.68% (mass fraction), which is 20% higher than that of pure LaNi_5. The activity of alloy is so good that the alloy is activated fully after 3 charging/discharging cycles. The discharge capacity of alloy reaches to 395mA·h/g, which is 23% higher than that of AB_5 type hydrogen storage alloys. After 100 charging/discharging cycles, 80% of the initial capacity can remain.