Ti、La对贮氢合金ZrMn0.7 V0.2 Co0.1 Ni1.2相结构和电化学性能的影响

研究了贮氢电极合金Zr1-xTixMin0.7V0.2Co0.1Ni1.2的相结构和电化学性能。结果表明，随着掺Ti量的增加，该合金主相中C15型Laves相含量逐渐减少而C14型Laves相含量逐渐增加，同时非Laves相Zr7M10和TiNi相全部消失，说明元素Ti掺杂量的增加抑制了第二相的产生。当含Ti量x=0．2时，该合金具有最大放电容量Cmax为354mAh／g，在放电电流为300mAh／g条件下，高倍率放电性能比母体合金提高了15％。而对于合金Zr0.75Ti0.2La0.05Mn0.7V0.2Co0.1Ni1.2，其活化性能被大大提高，只需4次就能达到最大放电容量372mAh／g，而且经过30次循环仍能保持最大放电容量的93％。

The effects of the substitution of Ti for ZrMn0.7V0.2CO0.1Ni1.2 storage hydrogen alloys on the phase structure and electrochemical properties

In this paper, phase structure and electrochemical properties of the hydrogen storage electrode alloys Zr_(1-x)Ti_x(Mn_(0.7)V_(0.2)Co_(0.1)Ni_(1.2))have been investigated. The results showed that when the Ti content increased, the content of the C15 Laves phase decreased while that of the C14 Laves phase increased. At same time, the Zr_7M_(10) phase and TiNi phase decomposed totally, which demonstrated high Ti content inhibited the appearance of second phase in the alloys. When x=0.2, the storage hydrogen electrode alloy Zr_(0.8)Ti_(0.2)(Mn_(0.7)V_(0.2)Co_(0.1)Ni_(1.2))possessed the maximum discharge capacity 354mAh/g, and preserved 91% of total capacity at current 300mA/g. In addition, due to doping La, the alloy Zr_(0.75)Ti_(0.2)La_(0.05)Mn_(0.7)V_(0.2)Co_(0.1)Ni_(1.2) reached the maximum capacity 372mAh/g after 4cycles, and preserved 93% of the maximum capacity after 30cycles.