(中南大學(xué) 冶金科學(xué)與工程系， 長沙 410083)
摘 要: 為了降低鎳氫電池的原材料成本，研究了一系列多元、低鈷和無鈷AB5型貯氫合金，以及取代元素對貯氫合金電化學(xué)性質(zhì)的影響。結(jié)果顯示，用少量的鐵、銅和鉻部分取代貯氫合金La(NiMnCoAl)5中的鈷對改善貯氫合金電化學(xué)循環(huán)穩(wěn)定性有效。貯氫合金La(NiMnAl)4.6(FeCuCr)0.2Co0.2具有滿意的循環(huán)穩(wěn)定性，它在0.2C放電條件下的最大放電容量為296 mAh／g-1，經(jīng)過300次循環(huán)容量衰減僅21.8%。另外，還用X射線衍射檢測了貯氫合金的微觀結(jié)構(gòu)。
關(guān)鍵字: 貯氫合金； 循環(huán)穩(wěn)定性； 電化學(xué)性質(zhì)； 容量
low-Co AB5-type hydrogen storage alloys
TAO Zhi-yong, HU Quang-yao
（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
