富铈稀土系低温贮氢合金的制备及性能研究  

Study on Preparation and Characterization of Low Temperature Hydrogen Storage Alloy from Mm Rare Earth

作　　者：王英[1] 唐仁衡[1] 肖方明[1] 彭能[1] 卢其云[1] 

机构地区：[1]广州有色金属研究院稀有金属研究所,广州510651

出　　处：《材料导报》2009年第22期52-55,共4页Materials Reports

基　　金：广东省自然科学基金资助项目(06026152);广州市招投标专项资助项目(2006Z1-D6101);广东省科技攻关项目(2006A10704002)

摘　　要：采用真空快淬法研究制备了富铈稀土系低温贮氢合金,考察了3种不同组成合金的放电性能。结果表明,Mm(NiCoAlMn)4.95合金大电流放电性能较好;添加微量元素后,可以提高其0.7C放电比容量、放电平台以及改善循环性能。经循环伏安性能测试发现,氢在合金电极中的扩散系数(DH=3.90×10-8cm2/s)较大;XRD分析显示合金具有单一CaCu5型相结构,晶粒尺寸小于50nm。用此合金组装的D8500型镍氢电池在-40℃、0.2C电流条件下,放电容量达到常温放电容量的70.72%。以1C电流充放电400次,电池容量保持率为93%,完全满足低温镍氢电池的要求。The Mm rare earth hydrogen storage alloy is synthesized by vacuum rapid quenching method. And three different alloys are studied. The results show that the alloy of Mm（NiCoAlMn）4. 95 has better large-current discharging performance. And its electrochemical properties, such discharge capacity, discharge voltage platform, cyclic life as well, are improved obviously. The bigger hydrogen coefficient（DH = 3. 90 ×10^-8cm2/s） of alloy electrode is obtained by cyclic voltarnmetry. While the single CaCu5-type phase structure of the alloy is determined by XRD, and its small grain size is less than 50nm. Then, the discharge capacity of D8500 Ni/MH battery, the alloy as material, can reach 70. 72% of normal atmospheric temperature capacity at --40℃ by 0. 2C. Moreover, the cell after 400 cycles at 1C, the capacity still has 93%, which satisfies the need of battery at low temperature.

关 键 词：低温贮氢合金 真空快淬 纳米晶 镍氢动力电池 

分 类 号：TG139.7[一般工业技术—材料科学与工程]