Electrochemical performances of as-cast and annealed La_(0.8-x)Nd_xMg_(0.2)Ni_(3.35)Al_(0.1)Si_0.05(x=0-0.4) alloys applied to Ni/metal hydride (MH) battery

作     者：Yang-Huan Zhang Hui-Ping Ren Tai Yang Chen Zhao Li-Cui Chen Hong-Wei Shang Dong-Liang Zhao 

作者机构：Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal ResourcesInner Mongolia University of Science and Technology Department of Functional Material ResearchCentral Iron and Steel Research Institute 

出 版 物：《Rare Metals》 (稀有金属（英文版）)

年 卷 期：2013年第32卷第2期

页      面：150-158页

核心收录：

学科分类：0808[工学-电气工程] 08[工学] 

基　　金：supported by the National Natural Science Foundation of China(Nos.51161015 and 50961009) the National High Technology Research and Development Program of China(No.2011AA03A408) the Natural Science Foundation of Inner Mongolia(Nos.2011ZD10 and 2010ZD05) 

主　　题：A2B7-type electrode alloy Substitution Lawith Nd Structure Electrochemical performance 

摘      要：The La-Mg-Ni-based A2B7-type Lao.8_xNdx ***.o5 （x = 0, 0.1, 0.2, 0.3, and 0.4） electrode alloys were prepared by casting and annealing. The influence of the partial substitution of Nd for La on the structure and electrochemical performances of the alloys was investigated. The structural analysis of X-ray diffraction and scanning electron microscopy reveals that the experimental alloys consist of two major phases： （La,Mg）2Ni7 with the hexagonal Ce2Ni7-type structure and LaNi5 with the hexagonal CaCus-type structure as well as some residual phases of LaNi3 and NdNis. The electrochemical measurements indicate that an evident change of the electrochemical performance of the alloys is associated with the substitution of Nd for La. The discharge capacity of the alloy first increases then decreases with the growing Nd content, whereas their cycle stability clearly grows all the time. Furthermore, the measurements of the high rate discharge ability, the limiting current density, and hydrogen diffusion coefficient all demonstrate that the electrochemical kinetic properties of the alloy electrodes first augment then decline with the rising amount of Nd substitution.