Structure of Sn Doped AB_5 Non-Stoichiometric Hydrogen-Absorbing Alloys-Ⅰ

ＡＢ5 ｔｙｐｅａｌｌｏｙｓａｒｅｗｉｄｅｌｙｕｓｅｄａｓｔｈｅｎｅｇａｔｉｖｅｍａｔｅｒｉａｌｓｏｆｎｉｃｋｅｌｍｅｔａｌｌｉｃｈｙｄｒｉｄｅｂａｔｔｅｒｉｅｓ (Ｎｉ ＭＨ )ｂｅｃａｕｓｅｏｆｔｈｅｅｘｃｅｌｌｅｎｔｐｅｒｆｏｒｍａｎｃｅｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｒａｐｉｄａｃｔｉｖａｔｉｏｎ ,ｈｉｇｈｅｎｅｒｇｙ ｓｔｏｒａｇｅｄｅｎｓｉｔｙ .Ｗｉｔｈｔｈｅｄｅｖｅｌｏｐ ｍｅｎｔｏｆｅｌｅｃｔｒｉｃｅｑｕｉｐｍｅｎｔｗｏｒｋｉｎｇａｔｌａｒｇｅｃｕｒｒｅｎｔ ,ｔｈｅｄｉｓｃｈａｒｇｅｒ…     

Electrochemical Properties of Sn Doped AB_5 Non-Stoichiometric Hydrogen Absorbing Alloys-Ⅱ

Ｒａｒｅｅａｒｔｈｈｙｄｒｏｇｅｎａｂｓｏｒｂｉｎｇａｌｌｏｙｓａｒｅｗｉｄｅｌｙｕｓｅｄｉｎｎｉｃｋｅｌ ｍｅｔａｌｌｉｃｈｙｄｒｉｄｅｂａｔｔｅｒｉｅｓ(Ｎｉ ＭＨ )ｂｅｃａｕｓｅｏｆｔｈｅｈｉｇｈｐｅｒｆｏｒｍａｎｃｅｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｔｈｅｓｅｍａｔｅｒｉａｌｓｉｎｒｅｓｐｅｃｔｔｏｅｎｅｒｇｙｄｅｎｓｉｔｙ ,ａｃｔｉｖａｔｉｏｎａｎｄｃｙｃｌｉｎｇｌｉｆｅ .ＴｈｅｒａｔｅｃａｐａｂｉｌｉｔｙｏｆＮｉ ＭＨｂａｔｔｅｒｉｅｓｍｕｓｔｂｅｉｍｐｒｏｖｅｄｇｒｅａｔｌｙｂｅｃａｕ…     

Manufacturing Process,Electrochemical Properties and Structures of Ml(NiMnTiCo)_5 Hydrogen Storage Alloys

Ｔｈｅｎｉｃｋｅｌｍｅｔａｌｈｙｄｒｉｄｅ（ＮｉＭＨ）ｓｙｓｔｅｍｉｓａｔｒａｃｔｉｖｅａｓａｓｅｃｏｎｄａｒｙｂａｔｅｒｙｂｅｃａｕｓｅｏｆｉｔｓｈｉｇｈｅｎｅｒｇｙｄｅｎｓｉｔｙａｎｄｌｏｗｌｅｖｅｌｏｆｐｏｌｕｔｉｏｎ．ＡＢ５ｔｙｐｅｈｙ...     

Abstracts of Papers in Journal of the Chinese Rare Earth Society

ＳｔｕｄｙｏｎＲｅｃｏｖｅｒｙＴｅｃｈｎｉｃｓｆｏｒＲａｒｅＥａｒｔｈｏｆＭＨ ＮｉＢａｔｔｅｒｙＮｅｇａｔｉｖｅＥｌｅｃｔｒｏｄｅＸｕＬｉｙａｎｇ ,ＣｈｅｎＺｈｉｃｈｕａｎ (ＳｈｅｎｚｈｅｎＨａｚａｒｄｏｕｓＷａｓｔｅＴｒｅａｔｍｅｎｔＳｔａｔｉｏｎ ,Ｓｈｅｎｚｈｅｎ 51 0 0 49,Ｃｈｉｎａ)Ａｂｓｔｒａｃｔ :Ｅｎｖｉｒｏｎｍｅｎｔａｌｐｒｏｔｅｃｔｉｏｎａｎｄａｂｓｅｎｃｅｏｆｒｅｓｏｕｒｃｅｐｒｏｖｏｋｅｐｅｏｐｌｅｔｏｐａｙａｔｔｅｎｔｉｏｎｔｏｔｈｅｒｅｕｓｅｏｆｕｓｅｆｕｌｍｅｔａｌｓｉ…     

Electrochemical Preparation of La—Fe Alloy Films in Dimethylsulfoxide（DMSO）

Ｒａｒｅｅａｒｔｈｓａｎｄｔｈｅｉｒａｌｌｏｙｓｈａｖｅｓｐｅｃｉｆｉｃｐｒｏｐｅｒｔｉｅｓ ,ｓｕｃｈａｓｍａｇｎｅｔｉｃ ,ｏｐｔｉｃａｌ,ｅｌｅｃｔｒｉｃａｎｄｈｙｄｒｏｇｅｎｓｔｏｒａｇｅ .Ｔｈｅｙｈａｖｅｂｅｅｎｗｉｄｅｌｙａｐｐｌｉｅｄｔｏｖａｒｉｏｕｓｆｕｎｃｔｉｏｎａｌｍａｔｅｒｉａｌｓ .ＴｈｅＬａ Ｆｅａｌｌｏｙｓｈａｖｅｂｅｅｎａｐｐｌｉｅｄａｓｍａｇｎｅｔｉｃｍａｔｅｒｉａｌｓ .Ｓｉｎｃｅｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓａｒｅｖｅｒｙａｃｔｉｖｅ,ｉｔｉｓｖｅｒｙｄｉｆｆｉｃｕ…     

Study on ER Suspensions of Polyparapheneylene Doped with Rare Earth

Ｅｌｅｃｔｒｏｒｈｅｏｌｏｇｉｃａｌ (ＥＲ)ｓｕｓｐｅｎｓｉｏｎｓａｒｅｐｒｅｐａｒｅｄｂｙｐｕｔｔｉｎｇｐａｒｔｉｃｌｅｓｗｉｔｈｈｉｇｈｄｉｅｌｅｃ ｔｒｉｃｃｏｎｓｔａｎｔｓｉｎｔｏｏｉｌｐｈａｓｅｗｉｔｈｌｏｗｄｉｅｌｅｃｔｒｉｃｃｏｎｓｔａｎｔｓ .Ｃｏｍｍｏｎｌｙ ,ｃｌａｙ ,ｓｉｌｉｃａｇｅｌ,ｓｔａｒｃｈａｎｄｓｏｏｎａｒｅｕｓｅｄ .ＳｏｍｅｒｅｓｅａｒｃｈｅｒｓｈａｖｅｓｔｕｄｉｅｄｔｈｅｐｒｅｐａｒａｔｉｏｎｏｆＥＲｓｕｓｐｅｎｓｉｏｎｓｂｙｐａｒｔｉｃｌｅｓｏｆｅａｓｙｐｏｌａｒ…     

Electrochemical Behaviors of Fe~(2 ) and Sm~(3 )in Urea-NaBr Low Temperature Melt and Their Inductive Codeposition

ＴｂＦｅ2 ｉｓｔｈｅｍａｘｉｍｕｍｍａｇｎｅｔｏｓｔｒｉｃｔｉｖｅｍａｔｅｒｉａｌａｔｔｈｅｐｒｅｓｅｎｔｔｉｍｅ .ＡｌｔｈｏｕｇｈｔｈｅλｏｆＳｍＦｅ2 ｉｓｓｌｉｇｈｔｌｙｌｏｗｅｒｔｈａｎｔｈａｔｏｆＴｂＦｅ2 ,ｂｕｔｔｈｅｍａｇｎｅｔｉｃｃｒｙｓｔａｌｏｆＳｍＦｅ2 ｈａｓｌｅｓｓａｎｉｓｏｔｒｏｐｙａｎｄｔｈｅｍａｇｎｅｔｏｓｔｒｉｃｔｉｓｎｅｇａｔｉｖｅ .Ｈｅｎｃｅ ,ｔｈｅＳｍＦｅ2 ｃａｎｂｅａｐｐｌｉｅｄｔｏｔｈｅｉｎｔｅｌ ｌｉｇｅｎｔｍａｔｅｒｉａｌｓｓｕｃｈａｓｔｙｐｉｎｇｈｅａｄ…     

Analysis of Photoelectric Hybridization Measurementon Shearing Force for Flat Shearer

ＡｎａｌｙｓｉｓｏｆＰｈｏｔｏｅｌｅｃｔｒｉｃＨｙｂｒｉｄｉｚａｔｉｏｎＭｅａｓｕｒｅｍｅｎｔｏｎＳｈｅａｒｉｎｇＦｏｒｃｅｆｏｒＦｌａｔＳｈｅａｒｅｒＱＵＺｈｉＨａｏＡｎａｌｙｓｉｓｏｆＰｈｏｔｏｅｌｅｃｔｒｉｃＨｙｂｒｉｄｉｚａｔｉｏｎＭｅａｓｕ...     

Use of Solid State Carbothermic Reduction in Production of Transition Metals and Their Carbides

Ｍａｎｙｔｒａｎｓｉｔｉｏｎｍｅｔａｌｓａｒｅｐｒｏｄｕｃｅｄｂｙｐｙｒｏｍｅｔ ａｌｌｕｒｇｉｃａｌｐｒｏｃｅｄｕｒｅｓｗｈｉｃｈｒｅｑｕｉｒｅｖｅｒｙｃｏｎｓｉｄｅｒａｂｌｅａｍｏｕｎｔｓｏｆｅｎｅｒｇｙ ,ｃｏｍｍｏｎｌｙｅｌｅｃｔｒｉｃａｌ.Ｏｎｔｈｅｏｔｈｅｒｈａｎｄ ,ｓｏｍｅｔｒａｎｓｉｔｉｏｎｍｅｔａｌｓａｒｅｏｂｔａｉｎｅｄｂｙｅｍｐｌｏｙ ｉｎｇｖｅｒｙｃｏｍｐｌｅｘｈｙｄｒｏｍｅｔａｌｌｕｒｇｉｃａｌｐｒｏｃｅｓｓｒｏｕｔｅｓ .Ｓｏｌｉｄｓｔａｔｅｃａｒｂｏｔｈｅｒｍｉｃｒｅｄｕ…     

国际会议预报

1、第 1 6届国际电力配电会议　将于 2 0 0 1年 6月 1 8～ 2 1日在荷兰阿姆斯特丹ＲＡＩ大会中心召开。会议由ＩｎｓｔｎｏｆＥｌｅｃｔｒｉｃａｌＥｎｇｉｎｅｅｒｓ (ＩＥＥ) ;ＡｓｓｎｏｆＥｌｅｃｔｒｉｃａｌＥｎｇｉｎｅｅｒｓ (ＡＩＭ) :ＩｎｔＣｏｎｆｏｎＥｌｅｃｔｒｉｃａｌＤｉｓｔｒｉｂｕｔｉｏｎ主持 ,与会论文 30 0篇 ,有 1 0 0 0人参加 ,欢迎投稿。联系 :ＡｎｎａＲｏｂｉｎｓｏｎ ,ＩＥＥ ,Ｅ Ｍａｉｌ:ｃｉｒｅｄ @ｉｅｅ .ｏｒｇ .ｕｋ ,ｈｔｔｐ :/ /ｗｗｗ .ｃｉｒｅｄ .ｏｒｇ .ｖｋ2、2 0 0 1年国际重型运输学会会…     

Degradation Behavior of Electrochemical Performance of Sealed-Type Nickel／Metal Hydride Batteries

The degradation mechanism of electrochemical performance of sealed-type nickel/metal hydride batteries was in-vestigated. The results indicate that the degradation behavior of Ni/MH battery is not only owing to the lack of electrolyte,but also the deterioration of the active materials on the positive and negative electrodes of Ni/MH batteries. Scanning electron micrographs (SEM), X-ray diffraction (XRD) and laser granularity analyses are presented. The particle pulverization and oxidation during charge/discharge are identified as the main causes for deterioration of the negative and positive electrode in nickel/metal hydride batteries, as well as the cross-section cracking of both anode and cathode.     

添加钕对Mg2Ni储氢合金的结构和电极性能的影响

利用两步法制备了一系列添加Nd的三元Mg2-xNdxNi合金。XRD分析证实，当x=0．05，0．1时，制得的三元Mg2-xNdxNi合金均为Mg2Ni单相合金；三元Mg18Nd0．2Ni(x=0．2，0．3)合金为三相合金，三相分别为Mg2Ni，NdNi，NdMgNi4。模拟电池测试结果表明，同Mg2Ni合金相比，球磨10h的三元Mg1．8Nd0．2Ni合金和Mg17Nd03Ni合金电极的放电容量提高明显，且Mg17Nd03Ni合金电极的循环性能有明显改善。这极有可能与合金中NdMgNi4相的存在以及球磨形成的微结构有关。     

钒基固溶体型贮氢合金的研究进展

金属钒具有吸氢量大、抗粉化性能好等优点，但是有效吸氢量较低，只有一半的氢能够释放出来，没有实用价值。在V-Ti二元合金的基础上形成的三元合金V-Ti-M(M代表Cr，Mn，Fe，Ni等)具有良好的贮氢性能。Ti／Cr比对V-Ti-Cr合金性能影响很大，Ti/Cr比值为0．75时V-Ti-Cr合金具有最大的贮氢量和有效吸氢量，同时热处理可以有效地提高V-Ti-Cr合金的有效吸氢量，并降低V的使用量。添加Mn的三元合金具有BCC和Laves相双相结构。V-Ti-Fe合金的贮氢量很高，并有希望利用便宜的钒铁做钒源。此外，V基固溶体合金还可以用于镍氢电池负极，如V-Ti-Ni合金具有很高的放电容量，目前需要解决其循环稳定性差和成本高的问题。     

Effect of cobalt content on electrochemical performance of La-Mg-Ni system （Ce2Ni7-type） electrode alloys

In order to improve the cyclic stability of La-Mg-Ni system （Ce2Ni7-type） alloy electrode, small amount of Co was added in La0.75Mg0.25Ni3.5 alloy. The effect of Co on electrochemical performance and microstructure of the alloys were investigated in detail. XRD results showed that the alloys had multiphase structure composed of （La, Mg）2Ni7, LaNi5 and small amount of LaNi2 phases. The discharge capacity of the alloys first increased and then decreased with increasing Co content. At a discharge current density of 900 mA/g, the HRD of the alloy electrodes increased from 81.3% （x=0） to 89.2 % （x=0.2）, and then reduced to 87.8 % （x=0.6）. After 60 charge/discharge cycles, the capacity retention rate of the alloys enhanced from 52.67% to 61.32%, and the capacity decay rate of the alloys decreased from 2.60 to 2.05 mAh/g per cycle with increasing Co content. The obtained results by XPS and XRD showed that the fundamental reasons for the capacity decay of the La-Mg-Ni system （Ce2Ni7-type） alloy electrodes were corrosion and oxidation as well as passivation of Mg and Lain alkaline solution.     

High Temperature Performances of Spherical Nickel Hydroxide with Additive Y2O3

The effect of Y2O3 as additive to the positive electrode on the high-temperature performances of the Ni-MH batteries was studied. The specific capacities of the positive electrode in Ni-MH battery at higher temperatures are much lower than usual. In order to improve high-temperature performances, charge/discharge curves of the Ni(OH)2 electrodes with different amounts of Y2O3 at different temperatures were studied. It is found that the specific capacities of the spherical Ni(OH)2 with Y2O3 as additive are much higher than those of the regular at higher temperatures. The specific capacity of Ni(OH)2 containing 1% Y2O3 at 0.2C C/D rate is 35% higher than that of the reguiar. The specific capacity of Ni(OH)2 containing 0.2% Y2O3 at 1C C/D rate is 15% higher than that of the regular. Mechanism of Y2O3 improving high temperature performances of Ni(OH)2 electrode was also discussed in detail.     

Effect of Cerium on Microstructure and Electrochemical Performance of Ti-V-Cr-Ni Electrode Alloy

Effect of cerium on the microstructure and electrochemical performance of the Ti0.25V0.35-xCexCr0.1Ni0.3（x=0,0.005）electrode alloy was investigated by X-ray diffraction（XRD）,field emission scanning electron microscopy/energy dispersive X-ray spectrometry（FESEM-EDS）,and electrochemical impedance spectroscopy（EIS）measurements.On the basis of XRD and FESEM-EDS analysis,the alloy was mainly composed of V-based solid solution with body-centered-cubic structure and TiNi-based secondary phase.Ce did not exist in two phases,instead,it existed as Ce-rich small white particles,with irregular edges,distributed near the grain boundaries of the V-based solid solution phase.Discharge capacity,cycle stability,and high-rate discharge ability of the alloy electrode were effectively improved with the addition of Ce at 293 K.It was very surprising that the charge retention was abnormal with larger discharge capacity after standing at the open circuit for 24 h.EIS indicated that addition of Ce improved the dynamic performance,which caused the charge transfer resistance（RT）to decrease and exchange current density（I0）to increase markedly.The exchange current density of the electrochemical reaction on the alloy surface with Ce addition was about 2.07 and 3.10 times larger than that of the alloy without Ce at 303 and 343 K,respectively.The diffusion coefficient of hydrogen（D）in the bulk alloy electrode decreased with addition of Ce,but it did not decrease so much,and the apparent activation energy（△rH）was far higher than that of the AB5 type alloy.     

Effect of Lu2O3 on Charge/discharge Performances of Spherical Nickel Hydroxide at High Temperature

Nickel-metal hydride （Ni/MH） batteries are one of promising batteries for electric vehicle applications, but at high temperature the charge efficiency of nickel electrode is very low. In order to improve the high-temperature-efficiency of nickel electrode, spherical nickel hydroxide mixed with various ratios of Lu2O3 was used as active material of pasted nickel electrodes. The results of charge/discharge experiments, cyclic voltammetric measurements and XRD characterizations have shown that after addition of Lu2O3, the oxygen evolution overpotcntial is elevated much, the charge efficiency of nickel electrode at high temperature is greatly improved and the content of β-NiOOH phase increases in charged electrodes. In addition, the mixed ratio of Lu2O3 has different effects on high temperature performances of nickel electrode at different charge/discharge currents, 3.5 % is the optimum mixed ratio, and the action of Lu2O3 on high temperature electrochemical behaviors is more apparent when nickel electrodes are charged at small current than large current.     

Properties of Ni and La Ni Electrode Materials Prepared by MVS

ＬａＮｉａｌｏｙａｓｏｎｅｏｆｃａｎｄｉｄａｔｅｓｆｏｒｈｙｄｒｏｇｅｎｓｔｏｒａｇｅｗａｓｆｉｒｓｔｐｒｅｐａｒｅｄｉｎ１９７０［１］．Ｓｉｎｃｅｔｈｅｎｌｏｔｓｏｆｆｕｎｄａｍｅｎｔａｌａｎｄｐｒａｃｔｉｃａｌｗｏｒｋｓｈａｖｅｂｅｅｎｐｕｂ...     

钒基固溶体贮氢合金研究现状

贮氢合金是MH/Ni电池技术的核心,为了满足镍氢电池作为动力电池的要求,开发低成本、高功率、高稳定性的贮氢合金,近年来人们在进一步提高其电化学性能方面做了大量工作。钒基固溶体贮氢合金是近年来开发的一种新型高性能贮氢材料。介绍了氢钒反应特点和钒基固溶体合金的制备方法,对无电化学活性的基质合金,用元素取代、合成复合合金和多相合金等多种方法,得到一些性能较好的负极材料。并对钒基固溶体贮氢合金的研究及开发现状进行了综述,指出了固溶体合金的研究方向。     

Electrochemical characteristics and synergetic effect of Ti0.10Zr0.15V0.35Cr0.10Ni0.30-10 wt.%LaNi5 hydrogen storage composite electrode

In order to improve performance of Ti-V-based solid solution alloy, electrochemical characteristics and synergetic effect of Ti0.10Zr0.15V0.35Cr0.10Ni0.30-10 wt.%LaNi5 hydrogen storage composite electrode prepared by two-step arc-melting were investigated system-atically. X-ray diffractometry (XRD) and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) showed that the main phase of composite alloy was composed of V-based solid solution phase with a BCC structure and C14 Laves phase with hexagonal structure, while secondary phase also existed in the composite alloy. The results showed that electrochemical characteristics of the composite alloy elec-trode were significantly improved. It was suggested that synergetic effect appeared in the maximum discharge capacity of the composite alloy, synergetic effect of the discharge capacity appeared in the activation process, in the composite process, in the cyclic process, in the discharge process at low/high temperature and at different current densities, and synergetic effect existed in the charge-transfer resistance and in the ex-change current density, which seemed to be related to formation of the secondary phase.