La_(0.7-x)Nd_xMg_(0.3)Ni_(3.4)Al_(0.1)(x=0～0.4)储氢合金的相结构及电化学性能

Phase Structure and Electrochemical Performance of La_(0.7-x)Nd_xMg_(0.3)Ni_(3.4)Al_(0.1)(x=0～0.4) Hydrogen Storage Alloy

采用真空烧结方式制备了AB3.5型La0.7-xNdxMg0.3Ni3.4Al0.1(x=0,0.1,0.2,0.3和0.4)储氢合金。XRD分析表明,所有合金均由LaNi5,La2Ni7和LaNi3三相组成。当Nd含量增加时,合金中的LaNi5和La2Ni7相含量有不同程度的增加,而LaNi3相相应减少。电化学性能测试表明,添加适量的Nd能改善合金电极的循环稳定性,其中La0.6Nd0.1Mg0.3Ni3.4Al0.1合金具有相对较好的综合性能,其最大放电容量达到322.4mAh.g-1,循环50周的容量保持率(S50)达到89.98%。

AB3.5typeLa0.7-xNdxMg0.3Ni3.4Al0.1 （ x = 0 -0.4） hydrogen storage alloys were prepared by sintering in vacuum. It was shown from XRD analysis that the alloys were mainly consisted of CaCu5-type LaNi5 phase, Ce2NiT-type La2Ni7 phase and PuNi3- type LaNi3 phase. With the increase of Nd content, LaNi5 phase and La2Ni7 phase in the alloy were increased and LaNi3 phase was decreased. The electrochemical performance experiments showed that the cycle life of the alloys could be improved by optimizing Nd content. The maximum discharge capacity of La0.6Nd0.1Mg0.3Ni3.4Al0.11 reached 322.4 mAh·g ^-1, and the capacity retention rate （S50） was 89.98% after 50 cycles.