锂离子电池有机电解液材料研究进展

综述了锂离子电池有机电解液材料的研究现状。锂离子电池有机电解液主要由电解质锂盐、有机溶剂和添加剂三个部分组成,新型电解质锂盐的研究开发可分为三个方面：（1）LiTFSI及其类似物;（2）络合硼酸锂化合物;（3）络合磷酸锂化合物。有机溶剂的研究工作主要集中在新型有机溶剂的开发上。最重要的添加剂主要有三类：（1）主要用以改善碳负极SEI膜性能的添加剂;（2）过充电保护添加剂;（3）配体添加剂。     

锂离子电池高温电解液

本文综述了适合高温锂离子电池用电解液的研究进展和发展前景。从电解质盐和溶剂的高温稳定性方面进行了论述,阐明了现有商用电解液体系在高温时的不足,提出了开发高温电解质盐、难燃有机溶剂、离子液体和阻燃添加剂的思路。通过官能团的修饰,可以克服现有锂盐的不足,开发出适用于高温条件的电解质盐。非碳酸酯类有机溶剂单独使用时的电化学性能较差,离子液体与常用正负极材料的兼容性有待改善,目前最有可能实用化的高温电解液是碳酸酯和阻燃剂的共混体系。通过引入多种阻燃元素或部分基团改进,可以合成出综合性能良好的阻燃剂,进而提高电解液的高温适用性。     

锂硫电池电解质研究进展

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Li₂S_n (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.     

锂离子电池非水电解质锂盐的研究进展

新型电解质锂盐主要包括含螯合硼阴离子、螯合磷阴离子、全氟膦阴离子、烷基磺酸阴离子、全氟烷基、亚胺基的有机锂盐及有机铝酸锂盐.本文综述了近年来在新型电解质锂盐研究与探索方面的成果,介绍了锂离子电池电解质锂盐的合成方法、组成与结构、化学和电化学性能及其与结构的关系,并阐述今后电解质锂盐研究的可能发展方向及研究方法.     

高浓度锂盐电解液

基于1 mol ·dm^-3 LiPF₆/EC的传统非水型电解液已在锂离子电池中应用了20年。高功率、高比能锂离子电池以及锂金属电池（如Li-O₂和Li-S）的发展,对电解液提出了更高的要求,使得电解液的研究与开发到了一个革新换代的阶段。研究者们已经在离子液体、聚合物电解质和无机固态电解质等新型体系研究方面取得一定的研究成果,但是这些新体系存在的本征问题使其商业化应用面临一定的困难。研究者们也开始重新审视已优化的常规液态电解液体系,高浓度锂盐电解液（>3 mol ·dm^-3）再次引起广泛关注。本文综述了高浓度锂盐电解液的发展历程、溶液结构特征、分类标准及其特殊的物理化学性能、锂离子传输性质和电解液/电极相容性;对高浓度锂盐电解液存在的主要问题进行了简要分析,提出了相应的改进措施,展望了高浓度锂盐电解液未来的发展方向,为新型电解液的开发提供了一条新思路。     

高安全、高比能固态锂硫电池电解质

锂硫电池具有理论能量密度高、成本低廉和环境友好等优点,是最有前途的下一代高比能二次电池系统之一。当前,基于有机电解液的液态锂硫电池存在多硫化锂穿梭效应、电解液易燃以及锂枝晶等问题,致使电池的库仑效率低、循环性能差,且存在严重的安全隐患。采用固态电解质(如凝胶聚合物、固态聚合物、陶瓷、复合电解质等)替代有机电解液是解决上述问题的有效途径。本文总结了近年来固态锂硫电池电解质的研究现状,评述了各类固态电解质的优缺点及改性策略,重点介绍了陶瓷固态电解质的研究进展。最后,对固态锂硫电池的未来发展趋势进行预测与展望。     

锂空气电池研究述评

由于锂空气电池具有很高的理论能量密度因而引起了广泛关注和研究。本文较为全面地论述了各种电解质体系中的锂空气电池的进展,包括:有机体系、水体系、离子液体体系、有机-水双电解质体系和全固态体系的锂空气电池;详细阐述和归纳了它们的工作原理和最新研究现状。对最新提出的锂-空气-超级电容电池的原理和特点进行了较详细的论述。结合氧气在有机电解质中的电化学还原行为指出单一有机电解质锂空气电池存在的问题以及可能的解决办法;同时展示了这类电池中空气电极催化剂的发展现状。结合双电解质锂空气电池、固态电解质锂空气电池、锂-空气-超级电容电池的结构阐述了它们各自的优缺点。本文还展示了一些可望用于单一有机电解质锂空电池、有机-水双电解质体系锂空电池的新型碳材料。最后对锂空气电池的研究发展进行了总结与展望,提出新型电解液、催化剂以及改进锂空气电池构造将会成为今后的发展趋势。     

锂及锂离子蓄电池有机溶剂研究进展

从有机溶剂对电池安全性的影响，氧化稳定性，与负极的相容性及对电解液电导率的影响四个方面，论述了锂及锂离子蓄电池有机溶剂的化学和电化学，介绍了碳酸酯类，醚类和羧酸酯类溶剂的性质与电极的相容性及在有机电解液中的应用，对含硫，硼基及胺类有机溶剂等也作了论述。     

锂电池电解液的分析方法

<正>申请公布号:CN106198813A申请公布日:2016.12.07申请人:凯思普科技有限责任公司摘要本发明涉及锂电池电解液的分析方法,锂电池电解液至少包括锂盐,锂盐包括至少一种含硼锂盐,该分析方法包括以下步骤:将待分析的电解液与甲醇水溶液混合,得到混合液;加热混合液至40~80℃,搅拌并保持8~24 h;停止搅拌,静置分层,分离出有机层;使用气相色谱仪分析有机层中     

锂二次电池中的原位聚合电解质

聚合物电解质主要分为凝胶聚合物电解质和固态聚合物电解质两种类型,均能够提升锂二次电池的性能。其中,凝胶聚合物电解质是利用增塑剂实现聚合物基质的凝胶化,将有机液态电解液固定在三维网络结构中,因此同时具备液态的离子扩散速率和固态材料的机械性能;而固态聚合物电解质是一种完全没有液态电解质的体系,利用聚合物基体的极性实现锂盐的解离,以聚合物分子链的运动实现离子传输。相对于传统的非原位法制备的聚合物电解质而言,原位聚合反应制备的聚合电解质能够有效改善电解质与电极的界面相容性、简化电池组装工艺、降低制造成本。本文综述了当前原位聚合电解质在锂二次电池中应用的研究进展,并展望了原位聚合电解质的应用前景和未来挑战。     

Thermodynamic properties of individual ions, calculated in terms of conception of real thermodynamic properties of individual ions in solutions

Real and chemical thermodynamic characteristics for several ions in mixtures of water with organic solvents of different classes are calculated on the basis of the proposed conception of real thermodynamic properties of individual ions in solutions. This conception is an improved and generalized version of the procedure for describing thermodynamic activity of individual ions in aqueous electrolyte solutions, which was successfully exploited for many years. The offered methodology enables one to determine thermodynamic characteristics of individual ions both in aqueous and nonaqueous electrolytes. The use of the Volta potential differences for determining real and chemical thermodynamic characteristics of individual ions in solutions is validated.     

Cycloalkane-based thermomorphic systems for organic electrochemistry: an application to Kolbe-coupling

The discovery that cycloalkanes can form thermomorphic systems with typical polar organic solvents has led to the development of less-polar electrolyte solutions. Their mixing and separation can be regulated reversibly at a moderate temperature range. The phase switching temperature can be controlled by changing the solvent compositions. While biphasic conditions are maintained below the phase switching temperature, conductive monophasic conditions as less-polar electrolyte solutions are obtained above the phase switching temperature. After the electrochemical transformations, biphasic conditions are reconstructed below the phase switching temperature, facilitating the separation of cycloalkane where hydrophobic products or designed hydrophobic platforms are selectively partitioned. Several polar organic solvents, including acetonitrile, methanol, and pyridine, can be used in this system according to the requirement of the reactions.     

锂电池用有机溶剂的纯化与效果

本文研究了碳酸丙烯酯(PC)、四氢呋喃(THF)、1,2-二甲氧基乙烷(DME)和γ-丁内酯(BL)的纯化及其去水效果。实验表明:本文所述纯化试剂方法,去水效果明显。     

Ion transfer at nanointerfaces between water and neat organic solvents

Nanopipet voltammetry was used for the first study of ion transfer (IT) reactions between aqueous solutions and neat organic solvents. An extremely wide ( approximately 10 V) polarization window obtained with no electrolyte added to the organic phase allows one to probe charge transfer reactions, which are not normally accessible by electrochemical techniques, for example, the transfer of l-alaninamide cation from water to 1,2-dichloroethane (DCE). While anions (e.g., chloride) and relatively hydrophobic cations (e.g., tetraalkylammonium ions) can be transferred from water to less polar neat solvents such as DCE, the transfers of strongly hydrated metal cations occur only in the presence of organic supporting electrolyte.     

The Effect of the Buffering Capacity of the Supporting Electrolyte on the Electrochemical Oxidation of Dopamine and 4‐Methylcatechol in Aqueous and Nonaqueous Solvents

Dopamine was electrochemically oxidized in aqueous solutions and in the organic solvents N,N‐dimethyl‐formamide and dimethylsulfoxide containing varying amounts of supporting electrolyte and water, to form dopamine ortho‐quinone. It was found that the electrochemical oxidation mechanism in water and in organic solvents was strongly influenced by the buffering properties of the supporting electrolyte. In aqueous solutions close to pH 7, where buffers were not used, the protons released during the oxidation process were able to sufficiently change the localized pH at the electrode surface to reduce the deprotonation rate of dopamine ortho‐quinone, thereby slowing the conversion into leucoaminochrome. In N,N‐dimethylformamide and dimethylsulfoxide solutions, in the absence of buffers, dopamine was oxidized to dopamine ortho‐quinone that survived without further reaction for several minutes at 25 °C. The voltammetric data obtained in the organic solvents were made more complicated by the presence of HCl in commercial sources of dopamine, which also underwent an oxidation process.     

A new access to Gibbs energies of transfer of ions across liquid|liquid interfaces and a new method to study electrochemical processes at well-defined three-phase junctions

Droplets of polar and nonpolar aprotic solvents containing dissolved electroactive species can be easily attached to paraffin-impregnated graphite electrodes. When the electrode with the attached droplet is introduced into an aqueous electrolyte solution, the electrochemical reactions of the dissolved species can be elegantly studied. Provided the droplet does not contain a dissolved electrolyte, the electrochemical reaction will be confined to the very edge of the three-phase junction droplet|graphite|aqueous electrolyte. When a neutral species is oxidised, two pathways are possible: the oxidised species can remain in the droplet and anions will be transferred from the aqueous solution to the organic solvent, or the oxidised species may leave the droplet and enter the aqueous solution. Depending on the nature of the dissolved species, the nature of the organic solvent, the presence or absence of appropriate anions and cations in the two liquid phases, very different reaction pathways are possible. The new approach allows studies of ion transfer between immiscible solvents to be performed with a three-electrode potentiostat. Electrochemical determinations of the Gibbs energy of ion transfer between aqueous and nonpolar nonaqueous liquids are possible, whereas conventional ion transfer studies require the presence of a dissociated electrolyte in the organic phase. The new method considerably widens the spectrum of accessible ions.     

Heterogeneous continuous flow synthetic system using cyclohexane-based multiphase electrolyte solutions

The discovery that supporting electrolytes can be effectively confined in typical organic solvents in a c-Hex-based multiphase electrolyte solution has led to the development of a novel heterogeneous continuous flow synthetic system. PTFE fiber functions as a separation filter that can efficiently isolate the c-Hex phase from multiphase electrolyte solutions. This system has demonstrated both electrochemical solvating and carbon-carbon bond forming reactions. Hydrophobic substrates can be introduced into the reactor as c-Hex solutions, which are then electrochemically transformed into the target hydrophobic products that pass through the PTFE fiber as c-Hex solutions.     

Thermochemistry of copper(II) ion solvation in aqueous organic solvents

The integral heat effects of CuCl₂ dissolution in aqueous DMSO, aqueous ethanol and aqueous acetone solutions at 298. 15 K in the electrolyte concentration range 0.001–0.01M were measured by means of calorimetry. ΔH _sol ⁰ values were obtained by extrapolation to zero electrolyte concentration. Literature data were used to determine the thermodynamic characteristics of Cu²⁺ transfer from water to aqueous organic solvents.     

Study on synthesis and electrochemical properties of a novel ferrocene-based compound and its application in anion recognition

The novel ferrocene-based compound 2-Fc is synthesized through the reaction of ferrocene carbonate acid and epoxy rosin E-51, and characterized by 1H NMR. The CV behaviors of 2-Fc in different organic solvents are recorded, and the major influential factors, namely, potential scan rate, concentration of electrolyte, and concentration of 2-Fc, and the mechanism of the electrode process are investigated. The CV behaviors of 2-Fc film on electrode in LiClO4 aqueous and organic solutions and the application of 2-Fc in H2PO4- recognition are also studied.