La_(0.7)Mg_(0.3)(Ni_(1-x)Co_x)_(3.5)(0≤x≤0.5)储氢合金电化学性能  

Electrochemical Behavior of La_(0.7)Mg_(0.3)(Ni_(1-x)Co_x)_(3.5) (0≤x≤0.5) Hydrogen Storage Alloys

作　　者：张海昌[1] 墨伟[1] 申元[1] 杨化滨[1] 周作祥[1] 周杏弟[2] 

机构地区：[1]南开大学新能源材料化学研究所,天津300071 [2]南开大学材料化学系,天津300071

出　　处：《中国稀土学报》2004年第5期712-714,共3页Journal of the Chinese Society of Rare Earths

基　　金：863计划(2003AA515022)资助项目

摘　　要：The effects of Ni/Co ratios on A2B7-type La0.7Mg0.3 (Ni1-xCox)3.5 （0≤x≤0.5） alloys were investigated. The results showed that the discharge capacity of the alloys first increased from 245 to 392 mAh·g-1, then decreased to 316 mAh·g-1, corresponding to x=0, 0.2 and 0.5, respectively. While the electrochemical impedance spectra indicated that the reaction resistance had the opposite tendency. When x is equal to 0.2, the reaction resistance has the lowest value. The electrochemical P-C-T results are consistent with the discharge ones of the alloys. When x is equal to 0.2, the dehydriding capacity is 1.34wt.%.The effects of Ni/Co ratios on A_2B_7-type La_(0.7)Mg_(0.3) (Ni_(1-x)Co_x)_(3.5) (0≤x≤0.5) alloys were investigated. The results showed that the discharge capacity of the alloys first increased from 245 to 392 mAh·g^(-1), then decreased to 316 mAh·g^(-1), corresponding to x=0, 0.2 and 0.5, respectively. While the electrochemical impedance spectra indicated that the reaction resistance had the opposite tendency. When x is equal to 0.2, the reaction resistance has the lowest value. The electrochemical P-C-T results are consistent with the discharge ones of the alloys. When x is equal to 0.2, the dehydriding capacity is 1.34wt.%.

关 键 词：La2Ni7型储氢合金 电化学性能 循环寿命 交流阻抗 电化学压力组成等温线 稀土 

分 类 号：TM912[电气工程—电力电子与电力传动]