Cycling stability of La-Mg-Ni-Co type hydride electrode with Al  

作　　者：孙现众 潘洪革 高明霞 李锐 林燕 马帅 

机构地区：[1]Department of Materials Science and EngineeringZhejiang University,Hangzhou 310027,China

出　　处：《中国有色金属学会会刊：英文版》2006年第B02期834-838,共5页Transactions of Nonferrous Metals Society of China

基　　金：Project (50131040) supported by the National Natural Science Foundation of China

摘　　要：The mechanism of the improvement of the cycling stability of the La-Mg-Ni-Co based hydrogen storage alloy electrode was systematically investigated. The results show that the cell volume expansion upon hydrogenation is obviously decreased after the partial substitution of Al for Ni. Therefore a decrease in the pulverization of the alloy particles is obtained, which leads to the decrease of the contact area of the fresh alloy surface with alkaline electrolyte and the increase of the charge/discharge efficiency. Moreover, the occurrence of Al in the alloy can create a dense Al oxide film on the surface of the alloy during charge/discharge cycling. This dense oxide film can prevent further oxidation of the active components in the alloy, which is believed to be the most important factor responsible for the improvement of the cycling stability of the La-Mg-Ni-Mn-Co-Al type alloy electrodes.The mechanism of the improvement of the cycling stability of the La-Mg-Ni-Co based hydrogen storage alloy electrode was systematically investigated. The results show that the cell volume expansion upon hydrogenation is obviously decreased after the partial substitution of Al for Ni. Therefore a decrease in the pulverization of the alloy particles is obtained, which leads to the decrease of the contact area of the fresh alloy surface with alkaline electrolyte and the increase of the charge/discharge efficiency. Moreover, the occurrence of Al in the alloy can create a dense Al oxide film on the surface of the alloy during charge/discharge cycling. This dense oxide film can prevent further oxidation of the active components in the alloy, which is believed to be the most important factor responsible for the improvement of the cycling stability of the La-Mg-Ni-Mn-Co-Al type alloy electrodes.

关 键 词：La-Mg-Ni-Co基合金 储氢合金 铝取代 氢化物电极 循环稳定性 

分 类 号：TG139.7[一般工业技术—材料科学与工程]