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1.
Studies of the electrolyte redistribution in a sealed nickel-cadmium battery with combined electrode design, fabricated using the separation fabric recommended for replacing the previously used and presently laid off perchlorovinyl fabric, were carried out.  相似文献   

2.
Relations for calculating the active resistance of electrolyte in pores of lead battery electrodes are proposed, and necessity for taking it into account in determining the active resistance of batteries is demonstrated.  相似文献   

3.
The effect of tin concentration on major characteristics of the Pb-0.08% Ca alloy was studied.  相似文献   

4.
郭丽敏  彭章泉 《分析化学》2013,41(2):307-314
基于锂-氧气反应的锂-空气电池在所有的锂电池体系中具有最大的理论容量和能量密度,认识锂-空气电池中的氧气电极反应对锂-空气电池的研发具有指导意义.本文以金电极/乙腈电解液为模型体系,介绍了锂-空气电池在放电和充电过程中的氧气电极反应机理.电池放电时,氧气还原成超氧自由基,超氧自由基与锂离子结合生成不稳定的超氧化锂;通过歧化反应,超氧化锂生成放电反应最终产物过氧化锂.电池充电时,过氧化锂通过一步两电子直接氧化生成氧气,不经过超氧化锂中间态.在阐述氧气电极反应机理的同时,还对研究氧气反应的各种电化学方法作了介绍.  相似文献   

5.
The slow flow of a multicomponent electrolyte solution in a narrow pore of a nanofiltration membrane is considered. The well-known semiempirical method of subdivision of electrical potential into quasi-equilibrium and streaming parts and the definition of streaming concentrations and pressure are discussed. The usefulness of this tool for solving the electrohydrodynamic equations is shown and justified: the use of a small parameter enables a system of electrohydrodynamic partial differential equations to be reduced to a system of ordinary differential equations for streaming functions. Boundary conditions for streaming functions at both the capillary inlet and outlet are derived. The proposed model is developed for the flow of a multicomponent electrolyte solution with an arbitrary number of ions. This is coupled with (i) the introduction of specific interactions between all ions and the pore wall and (ii) the inclusion of the dissociation of water in both conservation and transport equations. Effective distribution coefficients of ions are introduced that are functions of both the specific interaction potentials and the surface potential of the nanofiltration membrane material. The axial dependency of surface potential is expressed by the use of a charge regulation model from which the discontinuity in electric potential and ion pore concentrations at the pore inlet and outlet can be described.A relation between the frequently used capillary and homogeneous models of nanofiltration membranes is developed. An example of application of the homogeneous model for interpretation of experimental data on nanofiltration separation of electrolyte solutions is presented, which shows a reasonable predictive ability for the homogeneous model.  相似文献   

6.
锂离子电池用凝胶聚合物电解质研究进展   总被引:2,自引:0,他引:2  
凝胶聚合物电解质是制备高功率密度和高能量密度、长循环寿命的聚合物锂离子电池的重要材料之一。凝胶聚合物电解质由聚合物基体、锂盐和增塑剂等组成。本文重点论述了凝胶聚合物电解质各组成成分的相互作用以及近几年聚合物基体与增塑剂的研究进展。此外,对凝胶聚合物电解质的性能改进进行了讨论,并对凝胶聚合物电解质的应用前景进行了展望。  相似文献   

7.
为了提高锂离子电池电解液的热稳定性,使用亚磷酸三甲酯TMP作为溶剂来配置锂离子电池电解液,研究该电解液燃烧性能、电化学性能和热稳定性,并与商业用电解液作了比较.循环性能测试结果表明,亚磷酸三甲酯基电解液与正极材料LiNg0.8Co0.2O2有很好的相容性,有良好的电化学稳定性,而且与PC组成电解液时可一定程度地抑制PC对负极石墨材料的剥离.燃烧试验和微量量热实验表明,TMP的加入能显著地提高电解液的热稳定性与安全性能.  相似文献   

8.
The zeta potential is an important and reliable indicator of the surface charge of membranes, and knowledge of it is essential for the design and operation of membrane processes. The zeta potential cannot be measured directly, but must be deduced from experiments by means of a model. The possibility of determining the zeta potential of porous membranes from measurements of the electrolyte conductivity inside pores (lambda(pore)) is investigated in the case of a ceramic microfiltration membrane. To this end, experimental measurements of the electrical resistance in pores are performed with the membrane filled with KCl solutions of various pHs and concentrations. lambda(pore) is deduced from these experiments. The farther the pH is from the isoelectric point and/or the lower the salt concentration is, the higher the ratio of the electrolyte conductivity inside pores to the bulk conductivity is, due to a more important contribution of the surface conduction. Zeta potentials are calculated from lambda(pore) values by means of a space charge model and compared to those calculated from streaming potential measurements. It is found that the isoelectric points are very close and that zeta potential values for both methods are in quite good agreement. The differences observed in zeta potentials could be due to the fact that the space charge model does not consider the surface conductivity in the inner part of the double layer. Measurements of the electrolyte conductivity within the membrane pores are proved to be a well-adapted procedure for the determination of the zeta potential in situations where the contribution of the surface conduction is significant, i.e., for small and charged pores. Copyright 2001 Academic Press.  相似文献   

9.
室温离子液体电解质与碳负极材料间的相容性是其应用于锂离子电池的关键问题之一.本文总结了室温离子液体电解质体系与碳负极材料相容性的研究现状和微观机制,阐述了不同种类的室温离子液体与碳负极材料相容性的规律和存在的问题以及改善方法.  相似文献   

10.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

11.
Redox chemistry is the cornerstone of various electrochemical energy conversion and storage systems, associated with ion diffusion process. To actualize both high energy and power density in energy storage devices, both multiple electron transfer reaction and fast ion diffusion occurred in one electrode material are prerequisite. The existence forms of redox ions can lead to different electrochemical thermodynamic and kinetic properties. Here, we introduce novel colloid system, which includes multiple varying ion forms, multi‐interaction and abundant redox active sites. Unlike redox cations in solution and crystal materials, colloid system has specific reactivity‐structure relationship. In the colloidal ionic electrode, the occurrence of multiple‐electron redox reactions and fast ion diffusion leaded to ultrahigh specific capacitance and fast charge rate. The colloidal ionic supercapattery coupled with redox electrolyte provides a new potential technique for the comprehensive use of redox ions including cations and anions in electrode and electrolyte and a guiding design for the development of next‐generation high performance energy storage devices.  相似文献   

12.
The formation of lead sulfate in the active-material grains during discharge of a lead-acid battery is considered under the assumption that the grain size is not constant. The process is modeled for a binary grain distribution by size and its effect on the discharge is studied.  相似文献   

13.
The influence exerted by a reinforcing additive, an aqueous suspension of 4D fluoroplastic (Teflon), on the structural, physicochemical, and service characteristics of the positive electrode of the lead battery was studied. A paste with polymer and carbon additives, extending the service life of the lead dioxide electrode, was developed for industrial use.  相似文献   

14.
Variations in the electrolyte composition on cycling of nickel-zinc batteries were studied, and ways for its stabilization and service life prolongation were revealed.  相似文献   

15.
A novel-pulsed electrolyte cathode atmospheric pressure discharge (pulsed-ECAD) plasma source driven by an alternating current (AC) power supply coupled with a high-voltage diode was generated under normal atmospheric pressure between a metal electrode and a small-sized flowing liquid cathode. The spatial distributions of the excitation, vibrational, and rotational plasma temperatures of the pulsed-ECAD were investigated. The electron excitation temperature of H Texc(H), vibrational temperature of N2 Tvib(N2), and rotational temperature of OH Trot(OH) were from 4900?±?36 to 6800?±?108 K, from 4600?±?86 to 5800?±?100 K, and from 1050?±?20 to 1140?±?10 K, respectively. The temperature characteristics of the dc solution cathode glow discharge (dc-SCGD) were also studied for the comparison with the pulsed-ECAD. The effects of operating parameters, including the discharge voltage and discharge frequency, on the plasma temperatures were investigated. The electron number densities determined in the discharge system and dc-SCGD were 3.8–18.9?×?1014?cm–3 and 2.6?×?1014 to 17.2?×?1014?cm–3, respectively.  相似文献   

16.
锂离子电池纳米电极材料研究   总被引:29,自引:1,他引:29  
尤金跨  杨勇 《电化学》1998,4(1):94-100
采用XRD,TEM方法对纳米相电极材料的结构,形貌进行表征,并用循环伏安法,恒流充放电法对电极材料的嵌锂电化学行为进行研究。结果表明,由于纳米材料的微结构特性使萁 具有优越的嵌锂特性;1)锂离子嵌入电极材料内部的深度小,过程短,具 较大的比表面,有利于采用较大的电流对该电池进行充放电;2)具有较大的嵌锂空间位置,有利于增加电极的锂嵌容量。  相似文献   

17.
The lead sulfate formation during discharge of the negative electrode in a lead–acid battery working in an activation mode, i.e. at the electrolyte excess, is considered, together with the reaction in a separate grain of the active material. An analytical solution for the distribution of discharge parameters along the grain radius is found and analyzed for the simplest case.  相似文献   

18.
19.
用1B铅笔芯制成聚甲基丙烯酸甲酯包裹的铅笔芯电极。将此电极置于pH 2.20磷酸盐缓冲溶液中,在-1.5~+2.0V(vs.SCE)电位区间,以0.1V·s-1扫描速率连续扫描30圈使其活化。试验表明:在pH 4.8的乙酸盐底液中,核黄素在此电极上产生还原峰,其峰电位在-0.300V(vs.SCE)。其峰电流的导数与核黄素的质量浓度在1.88×10-4~0.376mg·L-1范围内呈线性关系,其检出限(3S/N)为4.42×10-5 mg·L-1,应用此方法测定了维生素B2片剂中核黄素的含量,所得测定值与其标示值相符。在此样品的基础上做加标回收试验,测得回收率在96.5%~111%之间,测定值的相对标准偏差(n=5)为2.5%。  相似文献   

20.
本文综述了金属锂二次电池中提高锂负极性能的研究进展。分别介绍了以下改性方法:对金属锂表面进行预处理,使其表面预先形成性能良好的固体电解质界面膜,或直接在其表面制备保护膜;在电解液中加入添加剂对锂电极进行表面改性;采用新型有机溶剂、离子液体、聚合物电解质、玻璃态固体电解质、塑晶固体电解质等电解质体系提高界面相容性;改进金属锂电极的制备工艺,如制备金属锂粉末多孔电极和电沉积锂电极、制备全固态薄膜锂电池以及利用物理方法处理锂电极。并在此基础上对今后的发展趋势进行了展望。  相似文献   

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