退火热处理对快淬态La_(15-x)Sm_xFe_2Ni_(76)Mn_5B_2储氢合金组织结构及电化学性能的影响  

Effect of Annealing Treatment on Structure and Electrochemical Properties of the Quenched La_(15-x)Sm_xFe_2Ni_(76)Mn_5B_2( x = 0,2,4,6) Hydrogen Storage Alloys

作　　者：胡学超[1] 闫慧忠[2,3] 熊玮[2,3] 李宝犬 

机构地区：[1]内蒙古电力科学研究院,内蒙古呼和浩特010020 [2]稀土冶金及功能材料国家工程研究中心,内蒙古包头014030 [3]包头稀土研究院,内蒙古包头014030

出　　处：《稀土》2015年第4期20-26,共7页Chinese Rare Earths

基　　金：国家自然科学基金项目(51061001);国家国际科技合作项目(2010DFB63510)

摘　　要：采用中频感应熔炼-快淬方法制备La15-xSmxFe2Ni76Mn5B2(x=0,2,4,6)型储氢合金。结构分析表明:快淬态La15-xSmxFe2Ni76Mn5B2(x=0,2,4,6)合金为多相结构,主相为La Ni5相,另外还有La3Ni13B2相和(Fe,Ni)相。快淬合金经1173 K保温3小时,而后随炉冷却到室温,随着Sm替代La的量不同,合金的组成相有着不同的变化。电化学测试表明,退火热处理明显提高了合金电极的最大放电容量,改善了合金电极的自放电性能。退火合金电极的高倍率放电能力均低于快淬合金,表明储氢合金电极的电化学动力学性能有所下降。La15-xSmxFe2Ni76Mn5B2 （x = 0,2,4,6） hydrogen storage alloys were prepared using a vacuum induction- quenching furnace. Structure analyses showed that the quenched La15-xSmxFe2Ni76Mn5B2 （x = 0,2,4,6 ） alloy had muhiphase structure including the main LaNi5 phase, La3Nil3B2 phase and （Fe,Ni） phase. The quenched alloy was annealed at 1173 K for 3 h and then cooling to room temperature. After annealing treatment, each phase had different variations with x. The electrochemical testing showed that annealing treatment could significantly improve the maximum discharge capacity of the alloy e-ectrodes and ameliorate the self discharge performance of the alloy electrode. Furthermore, the high rate discharge ability of the annealed alloys were lower than the quenched alloys, which indicated that the electrochemical kinetics properties of hydro- gen storage alloys decreased.

关 键 词：镍氢电池 储氢材料 La-Fe-B系合金 电化学性能 退火热处理 

分 类 号：TG139.7[一般工业技术—材料科学与工程]