La-Mg-Ni系储氢合金的电化学性能研究进展

Research Progress in Electrochemical Properties of La-Mg-Ni Hydrogen Storage Alloys

综合分析了La-Mg-Ni系储氢合金中La-Mg-Ni合金、La-Mg-Ni-Co合金、不含Co的多元La-Mg-Ni系合金和含Co的多元La-Mg-Ni系合金的的电化学性能,特别是最大放电容量、循环充放电性能和高倍放电性能。发现La-Mg-Ni-Co合金中的La0.67Mg0.33Ni2.5Co0.5的综合电化学性能最好,最大放电容量达到420.5mAh/g,循环放电性能S70为92.9%和高倍放电性能HRD900达到87.7%。Co元素的添加可以有效提高合金的最大放电容量和循环放电性能,其高倍放电性能相比多元La-Mg-Ni系合金有所增加,但是对于La-Mg-Ni合金反而降低。可见,元素的增加和复杂化对多元La-Mg-Ni系合金的综合电化学性能帮助不大。

The electrochemical properties of La-Mg-Ni based hydrogen storage alloy, including La-Mg-Ni al- loy, La-Mg-Ni-Co alloy, Co-free multiple La-Mg-Ni alloy and Co-included multiple La-Mg-Ni-Co alloy were reviewed. According to the comparative studies of the maximum discharge capacity, cycle charge-discharge performance and high rate discharge ability of La-Mg-Ni based alloy, the La0. 67 Mg0.33 Ni2.5 Co0.5 alloy shows the excellent comprehensive electrochemical properties. The maximum discharge capacity is 420. 5 mAh/g, the cycle charge-discharge performance S70 is 92.9% and the high rate discharge ability HRD900 is 87.7%. The addition of Co element could effectively im- prove the maximum discharge capacity, the cycle charge-discharge performance and the high rate discharge ability of La-Mg-Ni alloy, but depress the high rate discharge ability of Co-included multiple La-Mg-Ni alloy. The addition and complication of alloy element could offer less help for the comprehensive electrochemical properties of multiple La-Mg- Ni based alloy.