Effects of annealing treatment on the microstructure and electrochemical properties of low-Co hydrogen storage alloys containing Cu and Fe

被引：0
作者：
Suxia Yang
Zhiping Liu
Shumin Han
Wei Zhang
Jianzheng Song
机构：
[1] Yanshan University,State Key Laboratory of Metastable Materials Science and Technology
[2] Yanshan University,College of Environmental and Chemical Engineering
来源：
Rare Metals | 2011年 / 30卷
关键词：
hydrogen storage alloys; annealing; phase structure; microstructure; electrochemical properties;
D O I：
暂无
中图分类号：
学科分类号：
摘要：
The effects of annealing treatment on the microstructure and electrochemical properties of low-Co LaNi3.55Mn0.35Co0.20Al0.20Cu0.75Fe0.10 hydrogen storage alloys were investigated. X-ray diffraction (XRD) analysis indicated that annealing treatment remarkably reduced the lattice strain and defects, and increased the unit-cell volume. The optical microscope analysis showed that the as-cast alloy had a crass dendrite microstructure with noticeable composition segregation, which gradually disappeared with increasing annealing temperature, and the microstructure changed to an equiaxed structure after annealing the alloy at 1233 K. The electrochemical tests indicated that the annealed alloys demonstrated much better cycling stability compared with the as-cast one. The capacity retention at the 100th cycle increased from 90.0% (as-cast) to 94.7% (1273 K). The annealing treatment also improved the discharge capacity. However, the high rate dischargeability (HRD) value of the annealed alloy slightly dropped, which was believed to be ascribed to the decreased exchange current density and the hydrogen diffusion coefficient in alloy bulk.
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页码：464 / 469
页数：5
相关论文
共 116 条
[1]  
Ruiz F.C.(2008)Electrochemical characterization of AB Int. J. Hydrogen Energy 33 3576-undefined
[2]  
Castro E.B.(2009) alloys used for negative electrodes in Ni/MH batteries Int. J. Hydrogen Energy 34 9403-undefined
[3]  
Real S.G.(2002)Electrochemical performance studies on cobalt and nickel electroplated La-Mg-Ni-based hydrogen storage alloys J. Alloys Compd. 343 164-undefined
[4]  
Peretti H.A.(2003)The electrochemical properties of Co-free AB5 type MlNi J. Alloys Compd. 354 310-undefined
[5]  
Visintin A.(2000)Mn J. Rare Earths 18 226-undefined
[6]  
Triaca W.E.(2003)Al Acta Phys. Chim. Sin. 21 61-undefined
[7]  
Ding H.L.(2007)Sn Electrochim. Acta 52 2423-undefined
[8]  
Han S.M.(2003) hydride electrode alloys J. Power Sources 124 285-undefined
[9]  
Liu Y.(1998)Research of low-Co AB J. Alloy Compd. 269 254-undefined
[10]  
Hao J.S.(2005) type rare-earth-based hydrogen storage alloy electrodes J. Power Sources 148 105-undefined
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