Microstructure and electrochemical characteristics of La_(0.7)Ce_(0.3)Ni_(3.75)Mn_(0.35)Al_(0.15)Cu_(0.75-x)(V_(0.81)Fe_(0.19))_x hydrogen storage alloys  

作　　者：刘宝忠 胡梦娟 李安铭 吉力强 张宝庆 朱惜林 

机构地区：[1]School of Materials Science&Engineering,Henan Polytechnic University [2]Inner Mongolia Rare Earth Ovonic Metal Hydride Co.Ltd.

出　　处：《Journal of Rare Earths》2012年第8期769-774,共6页稀土学报（英文版）

基　　金：Project supported by National Natural Science Foundation of China(51001043);China Postdoctoral Science Special Foundation(201104390,20100470990);Program for Innovative Research Team(in Science and Technology)in the University of Henan Province(2012IRTSTHN007);Baotou Science and Technology Project(2011J1003);the Doctoral Foundation of Henan Polytechnic University(B2010-13)

摘　　要：Microstructure and electrochemical characteristics of La0.7Ce0.3Ni3.75Mn0.35Al0.15Cu0.75-x（V0.81Fe0.19）x hydrogen storage alloys were investigated. XRD indicated that La0.7Ce0.3Ni3.75Mn0.35Al0.15Cu0.75-x（V0.81Fe0.19）x alloys consisted of a single phase with CaCus-type structure, and the lattice parameter a and cell volume V increased with increasing x value. The maximum discharge capacity first increased from 319.0 （x=0） to 324.0 mAh/g （x=0.05）, and then decreased to 307.0 mAh/g （x=0.20）. The high-rate dischargeability at the discharge current density of 1200 mA/g first increased from 52.1% （x=0） to 59.1% （x=0.15）, and then decreased to 55.4% （x=0.20）. The hydrogen diffusion in the bulky alloy was responsible for the high-rate dischargeability. Cycling stability first increased with increasing x from 0 to 0.10 and then de- creased when x increased to 0.20, which was resulted fi＇om the synthesized effect of the improvement of the pulverization resistance and the decrease of corrosion resistance.Microstructure and electrochemical characteristics of La0.7Ce0.3Ni3.75Mn0.35Al0.15Cu0.75-x（V0.81Fe0.19）x hydrogen storage alloys were investigated. XRD indicated that La0.7Ce0.3Ni3.75Mn0.35Al0.15Cu0.75-x（V0.81Fe0.19）x alloys consisted of a single phase with CaCus-type structure, and the lattice parameter a and cell volume V increased with increasing x value. The maximum discharge capacity first increased from 319.0 （x=0） to 324.0 mAh/g （x=0.05）, and then decreased to 307.0 mAh/g （x=0.20）. The high-rate dischargeability at the discharge current density of 1200 mA/g first increased from 52.1% （x=0） to 59.1% （x=0.15）, and then decreased to 55.4% （x=0.20）. The hydrogen diffusion in the bulky alloy was responsible for the high-rate dischargeability. Cycling stability first increased with increasing x from 0 to 0.10 and then de- creased when x increased to 0.20, which was resulted fi＇om the synthesized effect of the improvement of the pulverization resistance and the decrease of corrosion resistance.

关 键 词：hydrogen storage alloy VFe alloy phase structure electrochemical property Ni/MH batteries rare earths 

分 类 号：TG139.7[一般工业技术—材料科学与工程] TM912.2[金属学及工艺—合金]