M.S.Zhao
,
Y.Z.Zeng
金属学报(英文版)
The crystal structure,the phase composition and the electrochemical characteristics of Zr0.9 Ti0.1(Ni1.1Mn0.7V0.2)x(x=0.90,0.95,1.00,1.05) alloys were investigated by means of XRD,SEM,EDS and electrochemical measurements.It was shown that all alloys are multiphase with C15 Laves phase as a main phase along with C14 phase and some secondary phases.And the amounts of the C14 phase and secondary phases in the four alloys increases with decreasing x.The results indicated that the various stoichiometric ratios have great effects on the electrochemical characteristics such as the maximum discharge capacity,discharge rate capability and self-discharge properties etc.for Zr0.9Ti0.1(Ni1.1Mn0.7V0.2)x(x=0.90,0.95,1.00,1.05)alloys.The hyper-stoichiometric Zr0.9Ti0.1(Ni1.1Mn0.7V0.20)1.05 exhibits the maximum discharge capacity of 332mAh·g^-1.The C14 phase and secondary phases seems to mprove discharge rate capability of the alloys.
关键词:
metal hydride electrode
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null
,
null
田晓
,
王鸿钰
,
段如霞
,
姚占全
,
刘建
,
云国宏
稀土
采用筛分法测试了La0.75Mg0.25Ni3.3Co0.5储氢合金粉的粒度分布.结果表明,随着合金颗粒度减小,相应颗粒度的合金含量(质量分数)几乎呈线性增加,从合金颗粒度为58 μm时的21％增加到38 μm时的29％.同时,选用不同颗粒度的La0.75Mg0.25Ni3.3Co0.5合金粉制备了储氢合金电极,研究了合金颗粒度对储氢合金电极的活化性能、最大放电容量、放电特性以及循环稳定性的影响规律与机制.研究表明,合金颗粒度的大小对合金电极的活化性能基本无影响,合金电极均具有好的活化性能,经1至2个循环后达到最大放电容量.随着合金颗粒度的减小,合金电极的最大放电容量持续增加,从合金颗粒度为58 μm时的332.5 mAh·g-1增加到38 μm时的最大值342.9 mAh·g-1;放电中值电位先降低后升高,由合金颗粒度为58 μm时的1.0302 V减小到45 μm时的0.9825 V,然后增加到38μm时的1.0141V;容量衰减速度呈现出先变慢后加快的变化规律.综合比较,在合金颗粒度为48μm时,La0.75 Mg0.25Ni3.3Co0.5储氢合金电极展示了最佳的综合电化学性能,电化学性能的改善主要归因于合金电极电荷转移速度的加速和内阻的减小.
关键词:
储氢合金
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金属氢化物电极
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合金颗粒度
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电化学性能
王宁
,
柴玉俊
稀有金属材料与工程
研究333 K时Ti0.17Zr0.08V0.35Cr0.1Ni0.3合金的循环稳定性和高温倍率放电性能.333 K时,当放电电流密度为60 mA/g时,Ti0.17Zr0.08V0.35Cr0.1Ni0.3合金第1次放电容量为450 mAh/g.随着充放电循环的进行,放电容量迅速降低.当放电电流密度为2400mA/g,截止电压为0.6V时,Ti0.17Zr0.08V0.35Cr0.1Ni0.3合金的放电容量仍达到160 mAh/g.并详细探讨影响以上合金电化学性能的因素.
关键词:
合金
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电化学性能
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金属氢化物电极
