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MH/Ni电池失效原因分析 总被引:3,自引:0,他引:3
为分析MH/Ni电池失效原因,对失效后的MH/Ni电池进行解剖。对负极进行充放电容量测定、电镜扫描、表面元素分析,对正极进行充放电容量测定、循环伏安分析。结果表明,正负极容量都降低,负极活性物质发生了粉化,元素发生了偏析;氢氧化镍的氧化电位升高,而还原电位降低,电极可逆性变差了。 相似文献
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本文研究了Cu/Ni电接触对在受到微动磨损时的电阻变化特性。当铜为样片而镍为触头时接触对的接触电阻明显比铜为触头而镍为样片时接触对的接触电阻更容易升高。因此,建议易氧化的铜作为接触对的触头材料。微动磨损区两端由于氧化磨屑堆积,接触电阻很容易升高。本文计算了Cu/Ni接触对的微动寿命分布参数,给出了可靠度随微动次数变化的曲线。 相似文献
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Kenichi Kadono Shinji Yamaguchi Noboru Morita Minoru Aoyagi Akio Tanaka Takahiro Ueno 《IEEJ Transactions on Electrical and Electronic Engineering》2011,6(1):58-64
A sliding contact is normally used to supply current to a rotating or moving object. The surface film formed on the sliding surface is important for ensuring reliability and long life. In the present study, the effects of preoperation conditions and initial surface condition are investigated. We examined the relation between sliding speed and chemical treatment for electrical sliding contact action. The initial surface condition and preoperation conditions greatly influence the contact voltage drop that occurs during operation. It is shown that stability of sliding contact can be achieved by appropriate surface treatment and preoperation conditions. © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
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电极表面修饰对MH/Ni电池性能的影响 总被引:2,自引:2,他引:2
对小型MH/Ni电池正负极片进行了修饰研究.实验结果表明:该方法可增强电极的导电性,降低电池的内阻,提高电池的充放电效率和大电流放电能力,改善了电极的电化学性能. 相似文献
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Huixian Wu Hooghan K. Cargo J. 《Device and Materials Reliability, IEEE Transactions on》2004,4(1):11-17
In this paper, physical failure analysis (FA) techniques including interconnect level and gate level deprocessing techniques and cross section analysis that have been developed will be discussed. Deprocessing techniques discussed include: wet chemical etching, reactive ion etching (RIE), parallel polishing, chemical mechanical polishing (CMP), and combinations of these techniques. Moreover, the detailed characterization of CMP process and gate level deprocessing will be presented. For the cross-section analysis of copper/low-k samples, focused ion beam (FIB) and mechanical polishing techniques will be discussed. FA challenges and new failure modes and reliability issues will also be addressed. 相似文献
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复杂重力坝坝基抗滑稳定可靠度问题中,研究变量个数多,隐式功能函数非线性程度高,使用传统响应面法求解时拟合精度不高、收敛困难、结构计算量大。针对该问题,提出了重力坝坝基抗滑稳定可靠指标估计的偏最小二乘-极限学习机(PLS-ELM)动态响应面法。采用适用于处理高维度、小样本、非线性回归问题的极限学习机模型(ELM)构建隐式功能函数的响应面,并采用偏最小二乘法(PLS)优化极限学习机模型的隐含层神经元个数和输入权值,将极限学习机响应面和蒙特卡洛模拟法相结合,并构造合理的迭代方式,实现极限学习机响应面动态更新和可靠指标求解。在此基础上对某重力坝挡水坝段进行坝基抗滑稳定可靠度分析,结果表明:该方法结构计算量少,响应面拟合精度和效率高,算法容易收敛且适用性广,易于与多种结构计算方法和软件结合,适用于实际工程的坝基抗滑稳定可靠度分析;工程实例中坝基抗滑稳定可靠指标为5.10,满足规范要求;软弱夹层的材料参数对重力坝抗滑稳定可靠度影响最大。 相似文献
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《家电科技》2015,(12)
空调内外机在过程以及售后实际使用中频繁出现电感类元器件出现线圈断问题,导致空调使用寿命变短,一直是困扰着空调生产企业以及电感类器件生产厂家的难题,严重影响产品质量,该问题长期存在没有得到有效解决方案。本文从电感类元器件失效机理、器件内部构造、器件应用环境、器件生产工艺等方面进行全面分析。通过器件失效机理、器件环境应力模拟分析等对电感类器件全方位分析论断,分析结果表明:电感类器件在生产过程中由于绕线过紧、焊接温度过高、焊接时间过长、人工焊接手法不规范等原因难以在实际应用环境中以较高的可靠性工作,最终在过程使用以及售后使用过程中出现线圈断失效。电感类元器件失效实际与器件本身生产工艺设计陷存在较大关联;从器件本身应用环境、器件可靠性设计评估、器件应用环境标准、器件生产工艺全面论证分析整改,从器件本身质量提升着手,进行全面、系统化提升器件质量。 相似文献
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对圆柱形MH/Ni、Cd/Ni电池封口后化成的技术条件进行了研究 ,指出实现该目标的关键是MH电极和Cd电极在封口后化成循环中首次充电中的行为。实验结果表明 ,分别采用经改性的MH电极和Cd电极配套组装的AA型MH/Ni和Cd/Ni电池 ,其封口后化成是能够实现的 ,且封口后化成的两种电池特性均高于开口化成所获得的同类电池。讨论了改性的MH电极和Cd电极在封口后化成中的行为及其在首次充电中可能的正面作用。 相似文献
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分析了航空镉镍蓄电池的使用现状和要求,论述了影响航空镉镍蓄电池低温放电性能的主要因素,并根据试验找出了解决的方法。验证结果表明,航空镉镍蓄电池的低温性能有了较大提高,现在可满足环境温度-18℃飞机发动机的启动要求。 相似文献
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We have investigated electrical and structural properties of Pt/Pd/Au ohmic contact on p-type GaN:Mg (2.5 × 1017 cm−3) using Auger electron spectroscopy (AES) and glancing angle x-ray diffraction (GXRD) analysis. It was shown that the specific
contact resistivity improved with increasing annealing temperature. The annealing of the contact at 600∘C for 2 min in flowing N2 atmosphere resulted in a specific contact resistivity of 3.1 × 10−5 Ω cm2. Both GXRD and AES depth profile results show that Ga3Pt5, Ga2Pd5, and Au7Ga2 phases are formed at the interface region between metal and GaN when annealed at temperatures 600∘C. Possible explanation is suggested to describe the annealing dependence of the specific contact resistivity of the Pt/Pd/Au
contacts. 相似文献
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Jong-Hyun Im Ho-Seung Jeon Joo-Nam Kim Jeong-Hwan Kim Gwang-Geun Lee Byung-Eun Park Chul-Ju Kim 《Journal of Electroceramics》2009,23(2-4):284-288
Ferroelectric SrBi2Ta2O9 (SBT) films on a p-type Si (100) wafer with a LaZrO x (LZO) buffer layer have been fabricated to form a metal-ferroelectric-insulator–semiconductor (MFIS) structure. The LZO thin film and SBT films were deposited by using a sol–gel method. The equivalent oxide thickness (EOT) value of the LZO thin film was about 8.83 nm. Also, the leakage current density of the LZO thin film is about 3.3?×?10?5 A/cm2 at bias sweeping voltage of ±5 V. SBT films were crystallized in polycrystalline phase with highly preferred (115) orientation. Also, the intensity of each pick slightly increased as thickness of SBT films increased. The C–V characteristics of Au/SBT/LZO/Si structure showed clockwise hysteresis loop. The memory window width increased as the thickness of SBT films increased. The leakage current density of Au/SBT/LZO/Si structure decreased as thickness of SBT films increased. 相似文献