电动车用动力铅酸蓄电池的研究进展

简要介绍了电动车用铅酸动力电池的发展情况,包括了电池板栅的合金选择及板栅设计、正负极板铅膏的配方、电解液配方、隔板材料和充电方式等方面的改进,提出了今后电动车用铅酸蓄电池的研究发展方向。     

正交表诸因素对铁电极充电效率的影响

铁镍蓄电池具有理论比能量高,原材料丰富,价廉,环保等优点.它有良好的应用前景.本文概述了铁镍电池现有的优点、缺点和铁电极的制作方法.本文通过正交实验探讨不同因素对铁电极充电效率的影响,着重讨论了电解质溶液中添加剂对铁电极充电效率的影响.在本文中铁电极充电效率从30%~60%被提高到80%,这将有助于实现铁镍电池的密封.     

钒电池充电过程中钒价态及其变化的现场分析

钒电池是一种具有能充电放电性能的新型二次电池。该电池以硫酸氧钒(VOS0_4)作为电解质,在充电过程阳极半电池中V(Ⅳ)被氧化为V(Ⅴ),阴极半电池中V(Ⅳ)先被还原为V(Ⅲ),然后V(Ⅲ)进一步被还原为V(Ⅱ)。文中研究了用电位滴定对两个半电池中充电时钒价态变化进行测定的方法,并设计了分析装置,实现了分析V(Ⅱ)时的防氧化保护。试验表明,该分析法设备简单、操作简便,易于实现现场快速分析。通过测定,能及时了解电池充电过程中钒不同价态的定量转变情况及其与开路电压的关系,可有效地监测电池的充电效率。     

一种适于高速充电的新型化学电源电极的研究

本文提出一种适于高速充电的新型化学电源电极，该电极体系在充电时，反应界面能迅速推移，使活性物质能迅速沉积在三维载体电极上，特别适用于强电流高速充电。充电时活性物质以固态沉积在电极表面，而放电时活性物质又溶解为液态。电极体系在充放电循环过程中活性物质是以固（态）－液（态）循环形式进行循环，因而可以保持新鲜的电极表面，防止固体电极表现活性物质的相变、脱落、变形等弊端，有利于延长电极的寿命，该电极体系可     

双向脉冲充电法对锂枝晶生成的抑制

采用双向脉冲电流充电方法取代传统的直流电充电方法, 研究了金属锂电极在有机电解液1 mol•L−1 LiPF6/碳酸乙烯酯(EC):二甲基碳酸脂(DMC)(1:1, V/V)中的充电过程. 锂电极的表面变化通过原位显微镜观测和交流阻抗谱进行检测. 原位显微镜观测结果显示, 在直流充电时锂电极上明显地出现了枝晶, 而在双向脉冲充电时, 枝晶的产生和生长受到了抑制. 交流阻抗谱结果显示在双向脉冲充电下, 锂电极的表面积增长较直流充电时缓慢. 这种抑制枝晶生长, 稳定锂沉积的新充电方法有望用于锂阳极二次电池.     

我们怎样讲解铅蓄电池中的化学反应

蓄电池是蓄积电能,以备需要时再将电能放出的仪器。如铅蓄电池及铁镍轻蓄电池。蓄电池中的变化是化学能和电能之间的反复转变。由化学能转变为电能时叫放电;由电能转变为化学能时叫充电。蓄电池在汽车,拖拉机,电话局,电灯公司,矿井,坦克,鱼雷以及潜水艇等发电装置中有着广泛的应用。     

非水体系中单分子层保护团簇在超微铂电极上的量子化充电

非水体系中单分子层保护团簇在超微铂电极上的量子化充电;单层保护团簇;量子化电容充电     

微电极研究单分子层保护团簇的量子化电容充电

利用微电极在二氯甲烷溶液中研究了单分子层保护金纳米团簇 ( MPCs)的量子化电容充电效应 .用示差脉冲伏安法及循环伏安法获得了明显的 5对量子化电容充电峰 ,并测量出单个 MPCs的平均电容 .单阶跃计时库仑法的研究表明 ,每对峰对应于一个电子的充入或放出 .求得电荷传递系数α=0 .44和反应速率常数 k0 =1 .65× 1 0 -2 cm/s.与常规铂电极相比 ,微电极可获得更明显的量子化充电峰 .     

钠离子电池正极材料NaNi1/3Co1/3Mn1/3O2高压衰减机理

首次通过简单的固相反应合成了NaNi_1/3Co_1/3Mn_1/3O₂材料,并对其合适的电化学工作条件进行了探索。在此基础上对其在高充电电压下的衰减机理进行了研究。通过非原位XRD和电化学阻抗谱等电化学手段综合分析高充电电压下的衰减机理,发现随着充电电压升高至4 V,界面层的不断增厚与材料结构的不可逆变化同时导致了电化学性能的衰减。     

实验室中铅蓄电池的使用和维护(一)

在化学实验室中,蓄电池的应用甚广,它是一种很重要的直流电源。一个蓄电池如果维护得法,可以耐久使用,否则就很易损坏。所以,每一个突验室里的工作人员都座具各使用和维护蓄电池的正确知识。但是,实际上很多人使用时往往不得其法,致使蓄电池不能发挥它应有的作用。作者有鉴于此,特地收集了一些材料,结合个人的经验,想纯从应用的观点出发,把蓄电池的原理、构造、特性、充电和放电的情况,以及使用时应加注意之处等等,略加阐述。希望读者阅后,能对蓄电池的性能,有一个适当的了解,因而便于做到物尽其用的目标。     

Effects of surface site distribution and dielectric discontinuity on the charging behavior of nanoparticles: a grand canonical Monte Carlo study

The surface site distribution and the dielectric discontinuity effects on the charging process of a spherical nanoparticle (NP) have been investigated. It is well known that electrostatic repulsion between charges on neighbouring sites tends to decrease the effective charge of a NP. The situation is more complicated close to a dielectric breakdown, since here a charged site is not only interacting with its neighbours but also with its own image charge and the image charges of all its neighbours. Coexistence of opposite charges, titration sites positions, and pH dependence are systematically studied using a grand canonical Monte Carlo method. A Tanford and Kirkwood approach has been applied to describe the interaction potentials between explicit discrete ampholytic charging sites. Homogeneous, heterogeneous and patch site distributions were considered to reproduce the titration site distribution at the solid/solution interface of natural NPs. Results show that the charging process is controlled by the balance between Coulomb interactions and the reaction field through the solid-liquid interface. They also show that the site distribution plays a crucial role in the charging process. In patch distributions, charges accumulate at the perimeter of each patch due to finite size effects. When homogeneous and heterogeneous distributions are compared, three different charging regimes are obtained. In homogeneous and heterogeneous (with quite low polydispersity indexes) distributions, the effects of the NP dielectric constant on Coulomb interactions are counterbalanced by the reaction field and in this case, the dielectric breakdown has no significant effect on the charging process. This is not the case in patch distributions, where the dielectric breakdown plays a crucial role in the charging process.     

光导薄膜表面静电荷积累过程的动力学特征

本文对电照相用高分子光导材料薄膜涂层的表面电性能进行了研究,确定了表面充电过程宏观动力学的表征方法、动力学方程以及影响电荷沉积速度的因素。     

THE KINETICS OF CHARGE-ACCUMULATING PROCESS ON THE SURFACE OF PHOTOCONDUCTIVE COATING FILM

The charge-accumulating process of polymeric photoconductive coating film used in electro-photography as well as factors controlling the charging rate have been studied, and the characteriza-tion of charging process and kinetic equation have been established.     

The determination of the free energy of an electrical double layer

A well-known charging process is used to obtain the free energy of an electrical double layer, in which the double layer is built up by a transfer of ions from one phase to another. The present study formulates proofs that this charging process cannot determine the free energy of an electrical double layer.     

The charging of a liquid dielectric upon its flow past a flat-plate

The charging of a liquid dielectric upon its flow past a flat-plate is considered. Analytical expressions for the density distribution of electric charge and charging current are derived. The dependences of the current and charge density distribution on the system parameters are investigated. The effect of the electric field that emerges owing to charge separation on the charging process is taken into account. Consideration of the electric field is shown to lead to lower values of the electric charge density and charging current. As the Debye number decreases, the charge density also decreases. The charging current increases with an increase in the Debye number.     

In-situ Study of Charge and Discharge of Ni-MH Battery Using the Combined Method of Electrochemistry and Microcalorimetry

An apparatus to study the battery system has been set up. The thermal effects of charge and discharge of Ni-MH batteries have been studied. The calorimetric measurements indicate that the net heat dissipation during charging is larger than that during discharging. It is observed that the ratio of heat dissipation to charging energy varies with charging capacity, and almost 90 percent of charging energy is lost as heat dissipation near the end of the charging process at 97.7 mA. A jump of thermal curve near the end of discharge due to a secondary electrode reaction has been observed.This revised version was published online in November 2005 with corrections to the Cover Date.     

Continuum Field Charging of Dielectric Spheroids

Classical continuum theory for field charging is applied in an analysis of the ionic charging of spheroidal dielectrics. Assuming that the particle orientation is fixed during the charging process, the saturation charge and charging rate are determined as functions of the orientation and aspect ratio of spheroids. For spheroids of small dielectric constants the saturation charge becomes the largest when the electric field is directed perpendicular to the major axis of the spheroid. For an ensemble of randomly oriented spheroids the average saturation charge can be approximated as the arithmetic average of the saturation charges for the spheroid with the electric field directed along the three principal axes of the spheroid. In addition, the ensemble average of the dimensionless charging rate of randomly oriented spheroids of moderate axial ratio approximates the dimensionless charging rate of a sphere. Copyright 2000 Academic Press.     

A Rechargeable Hydrogen Battery Based on Ru Catalysis

Apart from energy generation, the storage and liberation of energy are among the major problems in establishing a sustainable energy supply chain. Herein we report the development of a rechargeable H₂ battery which is based on the principle of the Ru‐catalyzed hydrogenation of CO₂ to formic acid (charging process) and the Ru‐catalyzed decomposition of formic acid to CO₂ and H₂ (discharging process). Both processes are driven by the same catalyst at elevated temperature either under pressure (charging process) or pressure‐free conditions (discharging process). Up to five charging–discharging cycles were performed without decrease of storage capacity. The resulting CO₂/H₂ mixture is free of CO and can be employed directly in fuel‐cell technology.     

Discrete electrostatic charge transfer by the electrophoresis of a charged droplet in a dielectric liquid

We have experimentally investigated the electrostatic charging of a water droplet on an electrified electrode surface to explain the detailed inductive charging processes and use them for the detection of droplet position in a lab-on-a-chip system. The periodic bouncing motion of a droplet between two planar electrodes has been examined by using a high-resolution electrometer and an image analysis method. We have found that this charging process consists of three steps. The first step is inductive charge accumulation on the opposite electrode by the charge of a droplet. This induction process occurs while the droplet approaches the electrode, and it produces an induction current signal at the electrometer. The second step is the discharging of the droplet by the accumulated induced charge at the moment of contact. For this second step, there is no charge-transfer detection at the electrometer. The third step is the charging of the neutralized droplet to a certain charged state while the droplet is in contact with the electrode. The charge transfer of the third step is detected as the pulse-type signal of an electrometer. The second and third steps occur simultaneously and rapidly. We have found that the induction current by the movement of a charged droplet can be accurately used to measure the charge of the droplet and can also be used to monitor the position of a droplet under actuation. The implications of the current findings for understanding and measuring the charging process are discussed.