Co替代对LaNi_(3.8)型贮氢合金的组织结构和电化学性能的影响（英文）  

Effects of Co Substitution for Ni on Microstructures and Electrochemical Properties of LaNi_(3.8) Hydrogen Storage Alloys

作　　者：钟成林[1] 晁栋梁[1] 朱丁[1] 陈云贵[1] 吴朝玲[1] 徐程浩[1] 

机构地区：[1]四川大学,四川成都610065

出　　处：《稀有金属材料与工程》2014年第3期519-524,共6页Rare Metal Materials and Engineering

基　　金：the National High Technology Research and Development Program of China(2011AA03A408)

摘　　要：系统研究了Co替代Ni对LaNi3．8型LaNi3．8-XCox（x=0．0，0．2，0．4，0．6）贮氢合金组织结构和电化学性能的影响。研究表明，所有合金都由LaNi5、Ce5Co19和Pr5Co19相组成。随着Co含量的增加，3个相的相丰度发生变化，而且单胞体积也相应的增加，这使得合金的放氢平台压降低到镍氢电池需要的范围（0．01～0．1MPa）。与LaNi铋相比，含co合金的循环性能得到改善。LaNi314Co0.4具有最大的放电容量，这一点与固态放氢量一致。LaNi36C002倍率放电性能最好，具有最人的交换电流密度（I0）和最小的电荷转移电阻（Rct）。The effects of Co partial substitution for Ni on the microstructures and the electrochemical properties of the LaNi3.8-type phase LaNi3.8.xCox （x=0.0, 0.2, 0.4, 0.6） alloys were systematically studied. All the alloys mainly consist of LaNi5-type phase, rhombohedral Ce5Co19-type phase and hexagonal PrsCOlg-type phase. With increasing Co content, the relative abundance of each phase changes while the cell volume increases monotonously, which lower the hydrogen desorption pressure down to the desirable range （0.01-0.1 MPa） for hydride electrode of Ni/MH battery. All the Co-containing alloys display an enhanced cycle ability compared to LaNi3.8 alloy. The LaNi3.4Co0.4 alloy has the biggest discharge capacity, which is consistence with the solid hydrogen desorption capacity of the alloy. The LaNi3.6Co0.2 alloy exhibits the best rate performance corresponding to its maximum exchange current density （lo） and minimum charge transfer resistance （Rot）.

关 键 词：贮氢合金 LaNi3 8 Co替代 电化学特性 

分 类 号：TG139.7[一般工业技术—材料科学与工程]