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1.
研究Pb(II)和H+离子浓度对全铅单液流电池正、负电极在复合石墨基体上电化学行为的影响.结果表明,PbO2正极和Pb负极的电极过程受电化学和扩散混合控制.Pb(II)氧化沉积成PbO2时出现成核环,铅负极成核过电位小,充放电电压差远小于PbO2正极,电池极化主要来自PbO2正极.增加H+浓度有利于降低PbO2正极和Pb负极的极化,但析氧、析氢副反应和腐蚀加重.增大Pb(II)浓度有利于抑制析氧,但PbO2正极充电电压升高,充放电电压差增大.Pb(II)浓度较低时,充放电过程中PbO2沉积层少许脱落,充电电压进一步降低且更趋平稳.为此,电解液中HBF4浓度以2 mol L-1为宜,Pb(II)浓度应在0.9 mol L-1以上.  相似文献   

2.
The difference of the electrolyte densities in the container and within pores of the active electrode paste was determined in discharge of sealed lead batteries with absorbed electrolyte. The data obtained can be used in designing sealed batteries.  相似文献   

3.
锂硫电池由于其高能量密度(理论高达2600 Wh/kg)、低成本、环境友好等优点而广受关注. 但是锂硫电池仍存在正极活性物质利用率低、循环性能差等问题. 造成这些问题的主要原因是易溶于有机电解液的中间产物聚硫锂Li2Sn (4≤n≤8)和不溶于有机电解液的硫化锂造成的. 简要介绍了锂硫电池体系的主要问题,并结合本研究小组的研究,对锂硫电池用电解质体系从有机电解液组成、电解液添加剂、聚合物电解质和无机固体电解质等方面进行了详细的综述,最后对电解质的发展前景进行了展望.  相似文献   

4.
锂离子电池电解质溶液的研究   总被引:1,自引:0,他引:1  
韩景立  刘庆国 《电化学》2000,6(1):116-118
本文报道了 5磺基水杨酸苯氧基硼酸锂 (LiB(SO3 )C6H3 (O) (COO)OC6H5)的合成及其在乙烯碳酸酯 (ED) /二甲基碳酸酯 (DMC)及丙烯酸酯 (PC) /二甲基亚砜 (DMSO)混合溶剂中电化学性能的研究 .  相似文献   

5.
新型锂离子电池聚合物电解质的制备   总被引:13,自引:1,他引:12  
应用倒相法,以PVDF-HFP(偏氟乙烯-六氟丙烯)的混合物为基体制备锂离子电池电解质基质,制得的多孔PVDF基质薄膜具有优良的化学性能及机械性能,其拉伸强度为102kg/cm2,吸附锂离子电池电解液(1mol/LLiPF6的EC/DEC溶液)的能力达到自身重量的350%以上,吸液后其室温电导率在10-3S/cm以上,用它组装成原理电池以后呈现了良好的电化学性能.  相似文献   

6.
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   

7.
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   

8.
报道了一种HBF4水溶液中的全铅液流电池,正、负电极电解液均采用Pb(BF42的HBF4水溶液.在酸性的四氟硼酸铅电解液中考察了石墨电极和玻碳电极作为工作电极的循环伏安性能,石墨电极较适于用作全铅液流电池的正、负电极.采用石墨电极作为电池的正、负电极并在四氟硼酸铅酸性电解液中进行充放电实验,其中Pb(BF42浓度分别为0.5、1.0和1.5 mol·L-1,且保持游离的HBF4浓度为1.0 mol·L-1.该电池为单液流电池,不需要隔膜分隔正、负极的电解液,电流密度为10、20和40 mA.cm-2,当限定充电容量为7.0 mAh.cm-2,放电电压截止到1.0 V时,平均库仑效率大于87%,平均能量效率大于68%;当电解液采用1.0或1.5 mol·L-1 Pb(BF42+1.0 mol·L-1HBF4水溶液时,在10及20 mA.cm-2电流下的能量效率最高可超过74%.  相似文献   

9.
陈龙  黄少博  邱景义  张浩  曹高萍 《化学进展》2021,33(8):1378-1389
动力电池领域对锂二次电池的能量密度和安全性提出了更高要求,研究高能量密度固态锂电池对发展新能源产业具有重要意义。相比传统的有机电解液锂离子电池,采用聚合物固体电解质的聚合物固态锂电池不但具有明显提升的安全性,而且能够匹配高容量电极材料,实现能量密度的有效提升。聚合物固态锂电池是最有前景的锂二次电池之一,然而聚合物固体电解质与锂负极间仍存在严重的界面副反应、锂负极表面易生长枝晶等问题。近年来,通过电解质成分调控、电解质力学性能提升、电解质/锂负极界面调控和匹配三维锂负极等手段,聚合物基固态锂电池性能明显提升。基于此,本文介绍了常见的聚合物固体电解质及其与锂负极间的界面挑战,从添加无机填料、使用高强度基底膜、分级层状结构设计、构筑界面缓冲层、交联网络设计以及固态锂负极保护等几个方面综述了提升聚合物基电解质/锂负极界面稳定性的最新研究成果,最后对解决聚合物固体电解质/锂负极界面兼容性的研发方向和发展趋势进行了展望。  相似文献   

10.
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   

11.
锂空气电池的能量密度是传统锂离子电池的5~10倍, 可与汽油相媲美。近几年来, 锂空气电池因此受到了人们的广泛关注。本文概述了锂空气电池正极材料和电解液的最新研究进展。从商业碳、具有特定形态的碳材料、催化剂、导电聚合物几个方面阐述了正极材料;从物质结构的角度, 简要介绍了锂空气电池中常用的酯类、醚类、砜类、胺类和离子液体等电解液。最后指出了目前锂空气电池存在的问题, 并对其进行了展望。  相似文献   

12.
锂空气电池的能量密度是传统锂离子电池的5~10倍,可与汽油相媲美。近几年来,锂空气电池因此受到了人们的广泛关注。本文概述了锂空气电池正极材料和电解液的最新研究进展。从商业碳、具有特定形态的碳材料、催化剂、导电聚合物等几个方面阐述了正极材料;从物质结构的角度,简要介绍了锂空气电池中常用的酯类、醚类、砜类、胺类和离子液体等电解液。最后指出了目前锂空气电池存在的问题,并对其进行了展望。  相似文献   

13.
提高电压是提高锂离子电池比能量的重要途径之一。例如,LiNi0.5Mn1.5O4(4.7 V)、LiNiPO4(5.1 V)和富锂锰基等电极材料在较高的充电截止电压下表现出较高的能量密度和较低的成本,具有很好的应用前景。另外,提高LiCoO2和三元电池体系的充电截止电压是提升电池能量密度的简单有效措施。但是,当电池充电截止电压提高时,不仅会造成电解液在正极/电解液界面的氧化分解,还会加速正极中金属阳离子在电解液中的溶解,造成电池循环性能和安全性下降。采用不同的正极界面修饰用电解液添加剂,既可以有效钝化正极/电解液界面,抑制电解液的分解,还可以有效抑制正极结构的破坏。本文从添加剂的分子结构出发,介绍了磺酸酯、硼酸酯、磷酸酯、氟代碳酸酯、腈类、酸酐和锂盐等添加剂在正极界面的相关研究成果,并对不同添加剂的作用机理进行了详细的解释和归纳;另外,介绍了添加剂的联用技术在不同电池体系中的最新研究成果;最后,对新型正极界面修饰用电解液添加剂的开发进行了展望。  相似文献   

14.
The transition to a sustainable society is paramount and requires the electrification of vehicles, the grid, industry, data banks, wearables, and IoT. Here, we show an all-solid-state structural battery where a Na+-based ferroelectric glass electrolyte is combined with metallic electrodes/current collectors (no traditional cathode present at fabrication) and thin-ply carbon-fiber laminates to obtain a coaxial multifunctional beam. This new concept aims to optimize the volume of any hollow beam-like structure by integrating an electrochemical system capable of both harvesting thermal and storing electrical energy while improving its mechanical performance. The coaxial cell is a coaxial cable where the dielectric is ferroelectric. The electrochemical results demonstrated the capability of performing three-minute charges to one-day discharges (70 cycles) and long-lasting discharges (>40 days at 1 mA) showing an energy density of 56.2 Wh·L−1 and specific energy of 38.0 Wh·kg−1, including the whole volume and weight of the structural cell. This is the highest specific energy among safe structural cells, while no Na+-based structural cells were found in the literature. The mechanical tests, instead, highlighted the coaxial cell capabilities to withstand severe inelastic deformation without compromising its functionalities, while increasing the flexural strength of the hosting structure. Moreover, the absence of alkali metals and liquid electrolytes together with its enhanced thermal properties makes this coaxial structural battery a valid and safe alternative as an energy reservoir for all the applications where traditional lithium-ion batteries are not suitable.  相似文献   

15.
随着大型移动设备(如新能源汽车等)、储能电站及其他便携式充电设备的日益普及,锂离子电池正逐步占领化学电源市场的主导地位。电解液是锂离子电池的重要组成部分,对电池的许多性能如输出电压、能量密度、输出功率、寿命、温度适用范围和安全性能等具有重要的影响。氟具有很强的电负性和弱极性,氟代溶剂或含氟添加剂具有低熔点、高闪点和高氧化分解电压等优点。氟代溶剂与电极材料之间的润湿性也较好,在高电压电解液、高安全性电解液、宽温度窗口电解液以及其他特殊功能电解液的开发中具有深入的研究和广泛的应用。本文综述了近年来氟代溶剂或添加剂在锂离子电池电解液中的不同应用,分析阐述了其对电池性能提升的机理,总结了以氟代碳酸乙烯酯(FEC)为代表的氟代溶剂的合成方法,最后对用于锂离子电池电解液的氟代溶剂或含氟添加剂的研发方向和发展趋势进行了展望。  相似文献   

16.
含FEC电解液的锂离子电池低温性能研究   总被引:2,自引:0,他引:2  
研究含FEC溶剂电解液(FEC+EMC,EC,PC)的低温性能及其与磷酸铁锂正极或中间相碳微球(MCMB)负极的匹配.该电解液具有较高的低温电导率,FEC可在1.6 V与负极反应成膜,有效地提高负极稳定性.红外测试发现,FEC可抑制其它电解液溶剂在负极成膜过程中的分解,在常温(20℃)和低温(-20℃)下形成的SEI膜阻抗均较低.电化学测试表明,以该电解液装配的锂离子电池(电极)具有较高的低温放电容量和倍率性能.  相似文献   

17.
增塑剂对聚合物电解质锂离子电池性能的影响   总被引:4,自引:0,他引:4  
锂电子;碳纤维;增塑剂对聚合物电解质锂离子电池性能的影响  相似文献   

18.
吴国民 《化学教育》2006,27(3):52-53
立足于中学化学的实际,从原电池的类型、构成条件、工作原理、电动势的产生机理等方面进行了定性阐述,适当拓展了原电池原理的有关知识,以适应素质教育的要求。  相似文献   

19.
Solid-state lithium-air battery represents one of the most promising energy storage systems to simultaneously achieve high energy density, safety, and cost-efficiency. Conventional inorganic solid electrolytes are not suitable for the lithium-air systems due to their spontaneous reactions with lithium and/or air. Meanwhile, the large-scale production of inorganic solid electrolytes at a low cost remains highly challenging to date. Recently, Yu et al. demonstrated that lithium-ion exchanged zeolite X membrane could be employed as the solid electrolyte for lithium-air battery owing to its unique microporous structure and the continuous ion-conduction pathway within a single crystal. Moreover, the lithium-ion exchanged zeolite X offers excellent compatibility with lithium and air and exhibits negligible air permeability. The integrated solid-state lithium-air battery exhibits superior electrochemical stability in ambient air compared to conventional liquid and solid electrolytes. Meanwhile, it offers flexibility, safety and tolerance against abuse. Since zeolites have been widely used in the chemical industry, this work opens up numerous opportunities in energy-related fields. The corresponding research has been published in Nature and can be accessed at https://www.nature.com/articles/s41586-021-03410-9.  相似文献   

20.
锂离子电池凝胶聚合物电解质改性的研究现状   总被引:3,自引:0,他引:3  
从目前凝胶聚合物电解质的研究现状及问题出发,重点介绍了两种改性凝胶聚合物电解质的方法。无机纳米粒子复合凝胶聚合物电解质能够降低结晶型聚合物的结晶度,提高其离子电导率,改善其力学性能和稳定性;多孔凝胶聚合物电解质能够实现在较宽的温度范围内能保持较高的离子电导率和较好的机械强度及尺寸稳定性。最后,对凝胶聚合物电解质的改性研究方向作出了展望。  相似文献   

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