摘要
通过感应容炼制备了La0.8-xRExMg0.2Ni3.2Co0.6(RE=Sm,Dy,0≤x≤0.3)合金。采用X射线衍射分析了该合金的晶体结构,并研究了其电化学性能。结果表明:该合金是由LaNi5主相和LaNi3第二相构成;随着Sm(Dy)取代La量的增加,合金主相单胞体积线性收缩,合金储氢量和放电容量减小,当Sm(Dy)取代量分别为0.1、0.2、0.3时,合金容量由380mA.h/g分别减小到370(362)、355(334)、329(295)mA.h/g,但高倍率放电能力和循环稳定性得到改善,100次循环后的容量损失率由20%分别降低到18%(17%)、16%(14%)、13%(11%)。
La0.8-xRExMg0.2Ni3.2CO0.6（RE=Sm, Dy, 0≤x≤0.3） alloys were prepared by inductive melting. The crystal structure of the alloys was determined by X-ray powder diffractrometry and the electrochemical properties were investigated. The results show that the alloys are composed of LaNi5 as matrix and LaNi3 as secondary phase. With the increasing Sm （Dy） substitution for La, the unit cell volume of matrix of the alloys shrinks linearly and both the hydrogen storage capacity and discharge capacity decrease. When the Sm （Dy） substitution （x value） is 0.1, 0.2 and 0.3, the discharge capacity decreases from 380 mA·h/g to 370（362）, 355（334） and 329（295） mA·h/g, respectively. However, the rate performance and cycle stability is improved. After 100 cycles, the capacity loss decreases from 20% to 18%（17%）, 16%（14%） and 13%（11%）.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2005年第7期1057-1061,共5页
The Chinese Journal of Nonferrous Metals
关键词
镍氢电池
储氢合金
稀土
放电容量
nickel-metal hydride hattery
hydrogen storage alloys
rare earth
discharge capacity
