锂离子电池用聚合物/无机复合固态电解质研究进展

全固态锂离子电池由于具有安全性高、能量密度高等优势,已成为未来锂离子电池发展的必经之路。作为全固态锂离子电池的核心部件,聚合物/无机复合固态电解质同时拥有无机固态电解质和固态聚合物电解质的许多优异性能,但其也面临着诸多挑战,包括室温离子电导率低于10~(-3)S/cm和界面阻抗大等。本文综述了聚合物/无机复合固态电解质的聚合物基体选择,探究了无机填料的种类及其改性方法,以及总结了复合固态电解质膜的制备工艺并对其未来可能的发展方向进行展望。     

锂电池用无机固态电解质

液态锂离子电池存在易燃易爆、易短路等致命的安全问题,同时也存在续航里程焦虑等技术问题,开发安全性能好、能量密度高的锂离子电池是行业发展的迫切需求。与传统液态锂离子电池相比,全固态电池具有使用安全、理论比容量高等优点,所以得到了广泛的研究,被誉为下一代电池主流技术。其中,无机固态电解质在全固态电池中扮演着重要的角色,国内外的科研人员对此进行了大量的研究工作。本文介绍了不同类型无机固态电解质的最新进展,其中包括氧化物固态电解质、硫化物固态电解质和卤化物固态电解质;并对无机固态电解质的界面问题、晶体结构、制备方法以及掺杂改性等方面的研究进行了阐述。最后,对近几年来无机固态电解质还有待解决的问题进行了讨论,同时对其未来的研究方向作出了展望。     

固态锂电池中正极/电解质界面的密度泛函计算研究（英文）

锂离子电池的广泛应用对储能器件的能量密度、安全性和充放电速度提出了新的要求.全固态锂电池与传统锂离子电池相比具有更少的副反应和更高的安全性,已成为下一代储能器件的首选.构建匹配的电极/电解质界面是在全固态锂电池中获得优异综合性能的关键.本文采用第一性原理计算研究了固态电池中电解质表面及正极/电解质界面的局域结构和锂离子输运性质.选取β-Li_3PS_4(010)/LiCoO_2(104)和Li_4GeS_4(010)/LiCoO_2(104)体系计算了界面处的成键情况及锂离子的迁移势垒.部分脱锂态的正极/电解质界面上由于Co-S成键的加强削弱了P/Ge-S键的强度,降低了对Li+的束缚,从而导致了更低的锂离子迁移势垒.理解界面局域结构及其对Li+输运性质的影响将有助于人们在固态电池中构建性能优异的电极/电解质界面.     

石榴石结构Li7La3Zr2O12固态电解质掺杂改性研究进展

锂离子电池是目前发展最快的化学储能电源,使用固态电解质的固态锂离子电池相比传统液态电解质锂离子电池能量密度更高,安全性更好,是下一代锂离子电池的发展方向。石榴石结构Li₇La₃Zr₂O₁₂(LLZO)固态电解质凭借较高的离子电导率、宽的电化学窗口及优异的稳定性,成为了最具商业前途的固态电解质之一。本文从石榴石结构LLZO电解质的发展脉络出发,剖析了石榴石结构LLZO电解质的结构特性、离子传导机制及其具有的高的结构稳定性和离子传导能力的本源,在此基础上综述了石榴石LLZO电解质的单元、双元、多元体相掺杂改性以提升电解质本征离子电导率,第二相掺杂改性以提升电解质的抗锂细丝生长能力、陶瓷致密度等性能,最后对石榴石结构LLZO电解质材料掺杂改性方向进行了分析和展望,为推动全固态锂离子电池电解质的发展提供参考。     

高陶瓷含量复合固态电解质

全固态锂二次电池兼具高能量密度和高安全性特点。高陶瓷含量的陶瓷-聚合物复合固态电解质综合了聚合物电解质的柔韧性和陶瓷电解质的高机械强度与高锂离子迁移数等优点,有望优先其他形式固态电解质应用于全固态锂二次电池。本文在简要介绍固态复合电解质后,重点从复合电解质膜的性能特点与制备方法、陶瓷-聚合物界面相互作用以及由此导致的新的离子传导机制等方面介绍高陶瓷含量陶瓷-聚合物复合固态电解质的研究进展。最后,展望了复合固态电解质所面临的一些基础科学与应用问题,并从陶瓷-聚合物界面相互作用角度提出未来复合固态电解质的研究方向和可能的解决方案。我们希望本文对于其他传导离子的复合电解质也有借鉴和启发意义。     

锂硫银锗矿固态电解质研究进展

全固态电池因其较高的安全性和能量密度而成为下一代电动汽车和智能电网用储能器件的重点研究方向之一。开发具有高室温锂离子电导率、化学/电化学稳定性优异、对电极材料兼容性优异等特点的固态电解质材料是推动全固态电池发展的重要研究课题之一。硫化物电解质因其相对较高的室温电导率(~10⁻³ S∙cm⁻¹)、较低的电解质/电极固-固界面阻抗等优点而在众多无机固体电解质材料中成为研究热点。本文基于作者多年研究成果和当前国内外发表的相关工作,从电解质的结构、离子传导、合成、综合性能改善及在全固态电池中的应用等方面系统总结了锂硫银锗矿固态电解质材料研究,并分析了该类电解质面临的问题和挑战,最后探讨了其未来可能的研究方向和发展趋势。     

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.     

卤化物固态电解质研究进展

全固态电池因其高能量密度和高安全性而成为具有发展前景的下一代储能技术。开发具有高室温离子电导率、优异化学/电化学稳定性、良好正/负极兼容性的固态电解质是实现全固态电池实用化的关键。卤化物固态电解质因其优异的电化学窗口、高正极稳定性、可接受的室温锂离子电导率等优势,受到了广泛的关注。本文通过对近年来卤化物电解质的相关研究进行总结,综述了该类电解质的组成、结构、离子传导路径及制备方法,并分析了金属卤化物电解质的电导率、稳定性特点,归纳了近年来该电解质在全固态电池中具有代表性的应用,并基于以上总结和分析,指出了卤化物固态电解质的研究难点及发展方向。     

固态聚合物电解质的锂离子传导机理与研究进展

锂离子电池(lithiumionbatteries,LIBs)在储能领域已取得了巨大的成功.然而,商用LIBs含有高挥发性易燃有机电解液,使其存在严重的安全隐患.固态聚合物电解质具有解决相应安全性问题的潜力,有望成为下一代高安全性全固态LIBs的电解质材料.然而,固态聚合物电解质存在离子电导率不高等问题,限制了其在固态LIBs中的实际应用.研究者们为了提高该类电解质的离子电导率、锂离子迁移数等综合电化学性能,已在寻找新锂盐、对聚合物进行改性以及向聚合物电解质中添加填料等方面进行了较多的研究.本文简要概述了固态聚合物电解质的锂离子传导机理以及在提高固态聚合物电解质综合电化学性能方面的研究进展.     

改性TiO2纳米球在可见光诱导抗菌中的应用

本研究以硫酸钛作为钛源,油酸为表面活性剂,尿素为氮源,采用简单有效的一步水热法,在180℃条件下反应6h制备了N掺杂的改性TiO2纳米球（N-TiO2）。N元素的成功引入,扩展了TiO2对光谱的响应范围,使其能够充分利用可见光产生活性氧（ROS）。在可见光照射下,这种N-TiO2纳米复合材料与原始的TiO2、商用的光催化剂德固赛P25-TiO2和Ag沉积的N-TiO2相比,在其周围产生透明的抑菌圈,而其余三种材料看不到明显的抑菌圈。这说明其对革兰氏阴性大肠杆菌具有明显的杀灭效果。     

Li7P3S11电解质的合成、传导及应用

固态电解质是固态电池中的关键材料,开发具有高离子电导率、高化学/电化学稳定性、电极兼容性良好的固态电解质正成为研究热点。硫化物固态电解质相较其它固态电解质具有更高的离子电导率和良好的机械加工性能等优势,是最有前景实现实用化的固态电解质之一。在众多硫化物固态电解质中,Li₇P₃S₁₁因其高的离子电导率和较低的原料成本而极具研究意义。本文首先介绍了Li₇P₃S₁₁电解质的结构、Li⁺传导机理及合成路径;其次,针对该电解质的电导率提高、空气/水稳定性提升、固固界面稳定性及电解质自身稳定性改善等问题,综述了目前常用的改性策略研究;再次,总结了基于Li₇P₃S₁₁电解质的全固态锂离子电池和全固态锂硫电池的构筑;最后,本文分析了Li₇P₃S₁₁电解质的研究和应用面临的挑战,并指出该电解质未来发展的趋势。     

PEO-LITFSI-SiO2-SN System Promotes the Application of Polymer Electrolytes in All-Solid-State Lithium-ion Batteries

All-solid-state polymer lithium-ion batteries are ideal choice for the next generation of rechargeable lithium-ion batteries due to their high energy, safety and flexibility. Among all polymer electrolytes, PEO-based polymer electrolytes have attracted extensive attention because they can dissolve various lithium salts. However, the ionic conductivity of pure PEO-based polymer electrolytes is limited due to high crystallinity and poor segment motion. An inorganic filler SiO₂ nanospheres and a plasticizer Succinonitrile (SN) are introduced into the PEO matrix to improve the crystallization of PEO, promote the formation of amorphous region, and thus improve the movement of PEO chain segment. Herein, a PEO₁₈−LiTFSI−5 %SiO₂−5 %SN composite solid polymer electrolyte (CSPE) was prepared by solution-casting. The high ionic conductivity of the electrolyte was demonstrated at 60 °C up to 3.3×10⁻⁴ S cm⁻¹. Meanwhile, the electrochemical performance of LiFePO₄/CSPE/Li all-solid-state battery was tested, with discharge capacity of 157.5 mAh g⁻¹ at 0.5 C, and capacity retention rate of 99 % after 100 cycles at 60 °C. This system provides a feasible strategy for the development of efficient all-solid-state lithium-ion batteries.     

New electrolytes using Li2O or Li2O2 oxides and tris(pentafluorophenyl) borane as boron based anion receptor for lithium batteries

A new system of electrolytes has been developed and studied for lithium-ion batteries. This new system is based on the interactions between Li₂O or Li₂O₂ and tris(pentafluorophenyl) borane (TPFPB) in carbonate based organic solvents. This opens up a completely new approach in developing non-aqueous electrolytes. In general, the solubility of Li₂O or Li₂O₂ is very low in organic solvents and the ionic conductivities of these solutions are almost undetectable. By adding certain amount of tris(pentafluorophenyl) borane (TPFPB), one type of boron based anion receptors (BBARs), the solubility of Li₂O or Li₂O₂ in carbonate based solvents was significantly enhanced. In addition, the Li⁺ transference numbers of these new electrolytes measured were as high as 0.7, which are more than 100% higher than the values for the conventional electrolytes for lithium-ion batteries. The room-temperature conductivities are around 1 × 10⁻³ S/cm. These new electrolytes are compatible with LiMn₂O₄ cathode for lithium-ion batteries.     

Halide Layer Cathodes for Compatible and Fast-Charged Halides-Based All-Solid-State Li Metal Batteries

Insertion-type compounds based on oxides and sulfides have been widely identified and well-studied as cathode materials in lithium-ion batteries. However, halides have rarely been used due to their high solubility in organic liquid electrolytes. Here, we reveal the insertion electrochemistry of VX₃ (X=Cl, Br, I) by introducing a compatible halide solid-state electrolyte with a wide electrochemical stability window. X-ray absorption near-edge structure analyses reveal a two-step lithiation process and the structural transition of typical VCl₃. Fast Li⁺ insertion/extraction in the layered VX₃ active materials and favorable interface guaranteed by the compatible electrode-electrolyte design enables high rate capability and stable operation of all-solid-state Li-VX₃ batteries. The findings from this study will contribute to developing intercalation insertion electrochemistry of halide materials and exploring novel electrode materials in viable energy storage systems.     

Recent progress and design principles of nanocomposite solid electrolytes

The electrochemical performance of all-solid-state batteries is largely determined by the physicochemical properties of the solid electrolytes. However, none of a single-type solid electrolyte can meet all practical requirements for all-solid-state batteries, including high ionic conductivity, wide electrochemical window, stable interfacial chemistry, robust mechanical properties, and so on. The nanocomposite solid electrolytes have provided a facile solution to address the above challenges, and great achievements have been made in this field. This review briefly summarizes the recent development of the nanocomposite solid electrolytes, focusing on the fundamentals of ionic charge transfer and chemical evolutions at the heterointerface. With the discussion, we hope to shed light on the rational design of solid electrolytes toward the optimal operational performance of all-solid-state batteries.     

A novel all-solid-state thin-film-type lithium-ion battery with in situ prepared positive and negative electrode materials

A novel all-solid-state thin-film-type rechargeable lithium-ion battery employing in situ prepared both positive and negative electrode materials is proposed. A lithium-ion conducting solid electrolyte sheet of Li₂O–Al₂O₃–TiO₂–P₂O₅-based glass–ceramic manufactured by OHARA Inc. (OHARA sheet) was used as the solid electrolyte, which was sandwiched by Cu and Mn metal films. The Cu/OHARA sheet/Mn layer became an all-solid-state lithium-ion battery after applying d.c. 16 V to the layer, and the resultant battery operated at 0.3–0.8 V with reversible capacity of 0.45 μAh cm^?2. High voltage battery was successfully prepared by applying the d.c. high voltage to a five-series of Cu/OHARA sheet/Mn layer, resulting in all-solid-state battery operating at 1.5–4.0 V. The proposed fabrication process will become a new technology to develop advanced all-solid-state rechargeable lithium-ion batteries.     

Revealing performance of 78Li2S-22P2S5 glass ceramic based solid-state batteries at different operating temperatures

78Li₂S-22P₂S₅ are sulfide electrolytes with high lithium-ion conductivity and wide electrochemical windows in the Li₂S-P₂S₅ system, making them attractive solid electrolytes for ASSLBs. However, the role and potential of 78Li₂S-22P₂S₅ solid electrolytes over a wide temperature range are still not fully understood. Therefore, we constructed solid-state batteries with NCM622 as the positive electrode and 78Li₂S-22P₂S₅ glass-ceramics as the electrolyte to investigate in depth the differences in battery performance over a wide temperature range and their intrinsic mechanisms. The in-situ impedance and relaxation time distribution (DRT) demonstrated the electrochemical stability of the electrolyte over a wide temperature range, while the in-situ stacking pressure observed a large volume change during cycling at 60 °C, leading to local solid-solid contact failure and poor cycling stability. This study provides insight into the advantages and problems of 78Li₂S-22P₂S₅ in the wide temperature range as well as a basis for the construction of ASSLBs with high energy density and long cycle life.     

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。     

三(三甲基硅烷)类添加剂助力5 V镍锰酸锂电池实用化

基于LiNi_0.5Mn_1.5O₄的5 V电池尚未实现实际应用,解决这一问题的关键在于电解液调控和电极界面优化。我们系统性研究了三（三甲基硅烷）硼酸酯（TMSB）和三（三甲基硅烷）亚磷酸酯（TMSPi）作为常规碳酸乙烯酯（EC）-LiPF₆基电解液添加剂在LiNi_0.5Mn_1.5O₄电池体系中的应用。结合理论计算、物理化学表征以及电化学手段分析了三（三甲基硅烷）类添加剂在高压电解液中的作用机制。研究发现,TMSB和TMSPi均可以通过优化电极/电解液界面来提高LiNi_0.5Mn_1.5O₄循环稳定性和库仑效率。TMSB中缺电子B可与阴离子相互作用,稳定PF₆^-,抑制LiNi_0.5Mn_1.5O₄正极阻抗的持续增加。TMSPi具有更高的最高占据分子轨道（HOMO）能级,可在更低电位下钝化高压正极,提高LiNi_0.5Mn_1.5O₄放电电压平台和放电容量。此外,TMSPi还可通过亲核反应参与石墨界面组分优化,改善负极循环性能。石墨LiNi_0.5Mn_1.5O₄软包电池在含1% TMSPi电解液中1C循环100次后的容量保持率为88.9%,优于基础电解液（60.5%）和含1% TMSB的电解液（77.4%）。