室温离子液体电解质与锂离子电池碳负极材料的相容性

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.     

有机硼酸锂盐及亚硫酸酯类功能电解质材料

随着锂离子电池对高安全性、高容量、高功率等性能的技术需求,新型功能电解质材料的研究开发成为锂离子电池新材料领域研发工作的重点.本文对面向锂离子电池应用的功能电解质材料锂盐和添加剂的最新研究进展作了较为全面的阐述,其中重点介绍了本研究团队近年来在面向改善锂离子电池安全性能、提高其温度适应性、增强电解质与电极材料相容特性等...     

锂离子电池LiBF4基液体电解质研究进展

LiBF4基电解质的热稳定性较好,对环境水分不太敏感,有希望发展成为被民用、军事、三航领域微型、储能及动力锂离子电池广泛采用的优秀电解质体系。本文综述了近期在改善LiBF4的电导率、拓宽应用温度范围、促进SEI膜的形成、提高其电解液电导率及与电极材料的相容性等方面所取得的进展,并对其未来发展方向作了展望。     

聚合物锂离子电池界面相容性的研究进展

聚合物锂离子电池作为储能装置在电子产品中具有广泛的应用前景。电极/聚合物电解质(E/P)界面相容性是影响聚合物锂离子电池电导率、安全性、机械性能的重要影响因素之一。研究E/P界面的电化学反应及形成机理,是解决相容性问题的关键。本文综述了近年来有关聚合物锂离子电池E/P界面相容性及相关研究技术的进展,并对聚合物锂离子电池界面相容性的相关研究进行了展望。     

聚合物锂离子电池界面相容性的研究进展

聚合物锂离子电池作为储能装置在电子产品中具有广泛的应用前景。电极/聚合物电解质(E/P)界面相容性是影响聚合物锂离子电池电导率、安全性、机械性能的重要影响因素之一。研究E/P界面的电化学反应及形成机理,是解决相容性问题的关键。本文综述了近年来有关聚合物锂离子电池E/P界面相容性及相关研究技术的进展,并对聚合物锂离子电池界面相容性的相关研究进行了展望。     

无机全固态锂离子电池界面性能研究进展

固体电解质不存在易燃等安全问题, 发展固态锂电池技术是解决液体电解质锂电池安全问题的根本途径. 随着社会对大体积锂离子电池需求的增长以及人们对电池的安全性关注度的日益提高, 发展固态锂离子电池已迫在眉睫. 制备性能良好的全固态锂电池的关键在于获得高室温离子导电率的固体电解质以及在电极与电解质之间形成良好的接触面. 大量的研究集中在制备高室温导电率的固体电解质, 目前已经制备出能与液体电解质相媲美的高室温导电率的固体电解质, 但固态锂电池的高倍率性能仍然较差, 原因是在电极与固体电解质的界面处具有较高的阻抗. 关于固态锂电池电极与电解质界面的研究文章相对较少. 本文简要介绍了一些具有高室温导电率的氧化物及硫化物电解质, 着重分析了全固态锂电池电极与电解质界面处具有高阻抗的原因以及减少界面阻抗的界面改性方法.     

固态锂金属电池中原位聚合电解质的研究进展

在下一代电池体系中,固态金属锂电池具有高能量密度潜力,同时有望避免目前电池面临的燃烧、爆炸等安全隐患.其中,固态电解质和电极材料之间的固-固界面接触差是其实用化面临的重要挑战.近年来,经电池内部原位聚合反应制得的原位聚合电解质用于固态锂金属电池具备界面一体化提升固-固界面相容性、抑制枝晶的形成、抑制正极过渡金属离子/多硫化物/氧化还原介质的溶解/穿梭并提升电池电化学性能多种优势.本文首先讨论了聚合电解质的反应机理,然后分析了电池内部常见电解质的原位聚合原理,总结了固态锂金属电池中原位聚合电解质的最新研究进展.最后,对未来原位聚合电解质的发展方向和商业化应用进行了展望.     

室温离子液体电解质与锂离子电池正极材料的相容性

室温离子液体作为新一代软功能介质材料,其电化学性质正在引起人们的广泛关注。本文综述了室温离子液体电解质在用于锂离子电池时与正极材料相容性的研究状况,总结了不同室温离子液体电解质与锂离子电池正极材料相容性的基本规律,从正极材料和室温离子液体两个方面探讨了改善室温离子液体/正极材料相容性的基本途径。     

固态聚合物电解质研究进展

开发下一代高安全且高能量密度能源体系是新能源产业进一步蓬勃发展的关键。将易燃易爆的液态电池替换为固态电池是一项极具前景的工作。在固态电解质中,聚合物电解质由于其高安全性、粘弹性及其良好的界面相容性等成为广泛研究的对象。但是在室温下其离子电导率仍然偏低,需要在高温下才能达到一定的电池性能。因此,在提升聚合物电解质常温离子电导率的同时,还需要进一步研究和改善电解质/电极之间的界面问题,降低界面阻抗。本文从固态聚合物的优缺点出发,介绍了不同固态聚合物电解质的性能及其离子传输机理,展望了固态聚合物电解质的最新研究进展和发展方向。     

离子液体/凝胶聚合物电解质的制备及其与LiFePO_4的相容性

以1-甲基-3-乙基咪唑六氟磷酸盐(EMIPF6)、聚偏氟乙烯-六氟丙烯(P(VDF-HFP))和六氟磷酸锂(LiPF6)为原料,采用溶液浇铸法制备了离子液体/凝胶聚合物电解质(ILGPE).通过循环伏安(CV)、计时电流法、恒流充放电、电化学阻抗法(EIS)研究了该电解质的离子传输特性以及与锂离子电池正极材料LiFePO4的相容性.结果表明,离子液体/凝胶聚合物电解质的室温电导率为1.650×10-3S·cm-1,电化学稳定窗口达到5.0V.在充放电循环过程中,电极表面形成的钝化膜改善了锂离子脱、嵌可逆性和电极/电解质的界面性质.     

Cross-linking copolymers of acrylates’ gel electrolytes with high conductivity for lithium-ion batteries

The cross-linking gel copolymer electrolytes containing alkyl acrylates, triethylene glycol dimethacrylate, and liquid electrolyte were prepared by in situ thermal polymerization. The gel polymer electrolytes containing 15 wt% polymer content and 85 wt% liquid electrolyte content with sufficient mechanical strength showed the high ionic conductivity around 5?×?10^?3 Scm^?1 at room temperature. The gel electrolytes containing different polymer matrices were prepared, and their physical observation and conductivity were discussed carefully. The cross-linking copolymer gel electrolytes of alkyl acrylates with other monomers were designed and synthesized. The results showed that copolymerization can improve the mechanical properties and ionic conductivities of the gel electrolytes. The polymer matrices of gels had excellent thermal stability and electrochemical stability. The scanning electron microscope analysis showed the gel electrolyte was the homogeneous structure, and the cross-linking polymer host was the porous three-dimensional network structure, which demonstrated the high conductivity of the gel electrolytes. The gel polymer Li-ion battery was prepared by this in situ thermal polymerization. The cell exhibited high charge-discharge efficiency at 0.1 C. The results of LiFePO4-PEA-Li cell and graphite-PEA-Li cell showed that gel polymer electrolytes have good compatibility with the battery electrodes materials.     

Challenges and Development of Composite Solid Electrolytes for All-solid-state Lithium Batteries

All-solid-state lithium batteries are considered to be a new battery system with great development potential and application prospects due to the advantages of high energy density and high security.As a key component of all-solid-state lithium batteries,the development of solid-state electrolytes has received extensive attention in recent years,but most solid electrolytes still exhibit problems,such as low ion conductivity and poor interface compatibility.The design of composite solid-state electrolyte materials with both excellent electrochemical and mechanical properties is an effective way to develop all-solid-state lithium batteries.This review introduces different types of pure component solid electrolytes and analyzes their respective advantages and characteristics firstly.Furthermore,the research progress of composite electrolytes in preparation method,ionic conduction,suppression of lithium dendrites,and the improvement of electrochemical performances are reviewed from the perspective of composite electrolyte structure design,which is to meet different performance requirements.And the future development direction and trend of composite electrolytes are prospected.     

Solid-state metal hydride secondary batteries using heteropolyacid hydrate as an electrolyte

In order to enhance the performance of a solid-state MnO₂-metal hydride battery using H₃PMo₁₂O₄₀ · 20H₂O as an electrolyte, a moderate amount of the electrolyte was added to both positive and negative electrodes. The high rate characteristics of the battery were improved significantly by optimizing the electrolyte content in the electrodes; the resulting battery was able to operate over 140 cycles, even at a current density of 20 mA/g alloy, which is large enough for the batteries using inorganic solid electrolytes, and keep the discharge efficiency about 90%. The improvement of battery performance appears to be caused by an increase in electrode-electrolyte interface area. The AC impedance analyses revealed that the resistance of interface is decreased by the addition of a suitable amount of the electrolyte, suggesting an increase in the interface area.     

高性能硫化物基全固态锂电池设计：从实验室到实用化

全固态锂电池因其优异的安全性和高能量密度成为储能领域的重点研究内容。硫化物电解质因其高离子电导率、良好电极/电解质界面兼容性及易加工性,有力推动了硫化物基全固态锂电池的发展。本文首先从实验室研究阶段出发,从正极/电解质界面、硫化物电解质自身及负极/电解质界面三方面阐述了硫化物基全固态锂电池现阶段面临的主要问题,并介绍了相关的解决策略。随后从硫化物基全固态锂电池的实用化生产角度出发,介绍了电极/电解质膜的制膜工艺、软包电池的装配相关问题、高载正极的设计及硫化物电解质的大规模、低成本制备。最后展望了硫化物基全固态锂电池的未来研究方向和发展趋势。     

XPS investigations of electrolyte/electrode interactions for various Li-ion battery materials

For future Li-ion battery applications the search for both new design concepts and materials is necessary. The electrodes of the batteries are always in contact with electrolytes, which are responsible for the transport of Li ions during the charging and discharging process. A broad range of materials is considered for both electrolytes and electrodes so that very different chemical interactions between them can occur, while good cycling behavior can only be obtained for stable solid-electrolyte interfaces. X-ray photoelectron spectroscopy (XPS) was used to study the most relevant interactions between various electrode materials in contact with different electrolyte solutions. It is shown how XPS can provide useful information on reactivities and thus preselect suitable electrode/electrolyte combinations, prior to electrochemical performance tests.     

An advanced model framework for solid electrolyte intercalation batteries

Recent developments of solid electrolytes, especially lithium ion conductors, led to all solid state batteries for various applications. In addition, mathematical models sprout for different electrode materials and battery types, but are missing for solid electrolyte cells. We present a mathematical model for ion flux in solid electrolytes, based on non-equilibrium thermodynamics and functional derivatives. Intercalated ion diffusion within the electrodes is further considered, allowing the computation of the ion concentration at the electrode/electrolyte interface. A generalized Frumkin-Butler-Volmer equation describes the kinetics of (de-)intercalation reactions and is here extended to non-blocking electrodes. Using this approach, numerical simulations were carried out to investigate the space charge region at the interface. Finally, discharge simulations were performed to study different limitations of an all solid state battery cell.     

A Designed Durable Electrolyte for High-Voltage Lithium-Ion Batteries and Mechanism Analysis

Rechargeable lithium-ion batteries (LIBs) dominate the energy market, from electronic devices to electric vehicles, but pursuing greater energy density remains challenging owing to the limited electrode capacity. Although increasing the cut-off voltage of LIBs (>4.4 V vs. Li/Li⁺) can enhance the energy density, the aggravated electrolyte decomposition always leads to a severe capacity fading and/or expiry of the battery. Herein, a new durable electrolyte is reported for high-voltage LIBs. The designed electrolyte is composed of mixed linear alkyl carbonate solvent with certain cyclic carbonate additives, in which use of the ethylene carbonate (EC) co-solvent was successfully avoided to suppress the electrolyte decomposition. As a result, an extremely high cycling stability, rate capability, and high-temperature storage performance were demonstrated in the case of a graphite|LiNi_0.6Co_0.2Mn_0.2O₂ (NCM622) battery at 4.45 V when this electrolyte was used. The good compatibility of the electrolyte with the graphite anode and the mitigated structural degradation of the NCM622 cathode are responsible for the high performance at high potentials above 4.4 V. This work presents a promising application of high-voltage electrolytes for pursuing high energy LIBs and provides a straightforward guide to study the electrodes/electrolyte interface for higher stability.     

全固态锂金属电池表界面化学的研究进展

传统的锂金属电池存在电解液易泄漏、 易燃等安全隐患, 因此开发不燃性全固态电解质对于解决锂金属电池安全问题至关重要, 而如何有效降低固体电解质与电极之间的界面电阻是发展高性能全固态锂金属电池的关键. 针对如何优化全固态锂金属电池表界面的问题, 本文综述了全固态锂金属电池电极和电解质表面修饰的最新研究进展, 对提高界面接触和降低界面电阻的传统方法进行了探讨, 分析并点评了新型的表面修饰技术, 为进一步提高全固态锂金属电池的综合性能提供新思路. 最后, 对全固态锂金属电池的研究前景进行了展望.     

高压锂离子电池电解液的研究进展

电极/电解液界面不稳定是高压锂离子电池发展的主要瓶颈.提高界面稳定性是高压锂离子电池得以应用的前提.本文综述了碳酸酯基电解液氧化分解反应机理、新型耐高压溶剂体系和新型成膜添加剂实验与理论的研究进展.     

Hybrid electrochemical capacitors in aqueous electrolytes: Challenges and prospects

In an internal hybrid capacitor, at least one electrode displays battery-like charge/discharge and the other electrode stores charge reversibly at the electric double-layer (EDL). Recently, a plethora of hybrid cells in aqueous electrolytes have been proposed by coupling an EDL electrode with a battery electrode, the latter made from a variety of redox-active/redox-mediator species either dissolved in the electrolyte or adsorbed/immobilized in nanoporous electrodes. This review presents current opinions, discusses challenges, and supplies recommendation about the hybrid cells with aqueous electrolytes and carbon electrodes.