(中南大学 冶金科学与工程系， 长沙 410083)
摘 要: 为了降低镍氢电池的原材料成本，研究了一系列多元、低钴和无钴AB5型贮氢合金，以及取代元素对贮氢合金电化学性质的影响。结果显示，用少量的铁、铜和铬部分取代贮氢合金La(NiMnCoAl)5中的钴对改善贮氢合金电化学循环稳定性有效。贮氢合金La(NiMnAl)4.6(FeCuCr)0.2Co0.2具有满意的循环稳定性，它在0.2C放电条件下的最大放电容量为296 mAh／g-1，经过300次循环容量衰减仅21.8%。另外，还用X射线衍射检测了贮氢合金的微观结构。
关键字: 贮氢合金； 循环稳定性； 电化学性质； 容量
low-Co AB5-type hydrogen storage alloys
（Department of Metallurgical Science and Engineering,
Central South University,Changsha 410083, P.R.China）
Abstract:A series of multi-component, low-cobalt and cobalt-free AB5-type hydrogen storage alloys were examined for lowering Ni-MH batteries raw materials cost. The effect of partial substitution of alloy components on the electrochemical properties was also investigated. The results show that a partial substitution of Co by a small amount of iron, copper and chromium is very effective in improving the electrochemical cycling stability in the La(NiMnCoAl)5 Alloy. A satisfactory cycling stability is obtained with an alloy composition of La(NiMnAl)4.6(FeCuCr)0.2Co0.2, which has a maximum capacity of 296 mA·h/g at a rate of 0.2C and whose capacity decay is 21.8% after 300 cycles at 1.0C rate. In addition, the alloys microstructure was examined by X-ray diffraction.
Key words: hydrogen storage alloys; cycling stability; electrochemical properties; capacity
