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Maxwell A. T. Marple Thomas A. Wynn Diyi Cheng Ryosuke Shimizu Harris E. Mason Prof. Y. Shirley Meng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22369-22377
Lithium phosphorus oxynitride (LiPON) is an amorphous solid-state lithium ion conductor displaying exemplary cyclability against lithium metal anodes. There is no definitive explanation for this stability due to the limited understanding of the structure of LiPON. Herein, we provide a structural model of RF-sputtered LiPON. Information about the short-range structure results from 1D and 2D solid-state NMR experiments. These results are compared with first principles chemical shielding calculations of Li-P-O/N crystals and ab initio molecular dynamics-generated amorphous LiPON models to unequivocally identify the glassy structure as primarily isolated phosphate monomers with N incorporated in both apical and as bridging sites in phosphate dimers. Structural results suggest LiPON′s stability is a result of its glassy character. Free-standing LiPON films are produced that exhibit a high degree of flexibility, highlighting the unique mechanical properties of glassy materials. 相似文献
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Naoaki Yabuuchi 《Chemical record (New York, N.Y.)》2019,19(4):690-707
Dependence on lithium‐ion batteries for automobile applications is rapidly increasing, and further improvement, especially for positive electrode materials, is indispensable to increase energy density of lithium‐ion batteries. In the past several years, many new lithium‐excess high‐capacity electrode materials with rocksalt‐related structures have been reported. These materials deliver high reversible capacity with cationic/anionic redox and percolative lithium migration in the oxide/oxyfluoride framework structures, and recent research progresses on these electrode materials are reviewed. Material design strategies for these lithium‐excess electrode materials are also described. Future possibility of high‐energy non‐aqueous batteries with advanced positive electrode materials is discussed for more details. 相似文献
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富锂材料xLi2MnO3·(1-x)LiMO2(0-1)和低廉的价格已引起人们的广泛兴趣. 但其首次充放电循环的较大不可逆容量损失、较差的倍率性能和循环过程的材料相变等关键问题制约了其发展. 富锂材料结构解析和充放电机理探索一直是研究的热点. 目前,富锂材料是否为固溶体仍有争论,首次充电4.5 V平台的氧流失机理已得到确认. 为了提高富锂材料的电化学性能,可从体相掺杂、表面包覆和结构形貌控制等方面对材料进行改性,其电化学性能有显著提升. 本文综述了富锂材料最新研究进展,归纳了相关制备方法,重点介绍了富锂材料的结构特点、锂嵌脱机理和改性方法,并展望了今后的研究方向. 相似文献
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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. 相似文献
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Tassilo M. F. Restle Christian Sedlmeier Holger Kirchhain Wilhelm Klein Gabriele Raudaschl‐Sieber Volker L. Deringer Leo van Wüllen Hubert A. Gasteiger Thomas F. Fssler 《Angewandte Chemie (International ed. in English)》2020,59(14):5665-5674
Solid electrolyte materials are crucial for the development of high‐energy‐density all‐solid‐state batteries (ASSB) using a nonflammable electrolyte. In order to retain a low lithium‐ion transfer resistance, fast lithium ion conducting solid electrolytes are required. We report on the novel superionic conductor Li9AlP4 which is easily synthesised from the elements via ball‐milling and subsequent annealing at moderate temperatures and which is characterized by single‐crystal and powder X‐ray diffraction. This representative of the novel compound class of lithium phosphidoaluminates has, as an undoped material, a remarkable fast ionic conductivity of 3 mS cm?1 and a low activation energy of 29 kJ mol?1 as determined by impedance spectroscopy. Temperature‐dependent 7Li NMR spectroscopy supports the fast lithium motion. In addition, Li9AlP4 combines a very high lithium content with a very low theoretical density of 1.703 g cm?3. The distribution of the Li atoms over the diverse crystallographic positions between the [AlP4]9? tetrahedra is analyzed by means of DFT calculations. 相似文献
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锂离子电池纳米正极材料 总被引:4,自引:0,他引:4
综述了锂离子电池纳米正极材料的研究进展,阐述了这种材料用于锂离子电池的优势和存在的问题,把纳米正极材料分为过渡金属嵌锂化合物、金属氧化物和金属硫化物和其它纳米正极材料。归纳了不同纳米正极材料的主要制备方法,探讨了材料的制备方法与其结构、形貌和电化学性能之间的关系,展望了纳米正极材料用于锂离子电池的未来前景。 相似文献
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Wontae Lee Shoaib Muhammad Chernov Sergey Hayeon Lee Jaesang Yoon Yong‐Mook Kang Won‐Sub Yoon 《Angewandte Chemie (International ed. in English)》2020,59(7):2578-2605
The accelerating development of technologies requires a significant energy consumption, and consequently the demand for advanced energy storage devices is increasing at a high rate. In the last two decades, lithium‐ion batteries have been the most robust technology, supplying high energy and power density. Improving cathode materials is one of the ways to satisfy the need for even better batteries. Therefore developing new types of positive electrode materials by increasing cell voltage and capacity with stability is the best way towards the next‐generation Li rechargeable batteries. To achieve this goal, understanding the principles of the materials and recognizing the problems confronting the state‐of‐the‐art cathode materials are essential prerequisites. This Review presents various high‐energy cathode materials which can be used to build next‐generation lithium‐ion batteries. It includes nickel and lithium‐rich layered oxide materials, high voltage spinel oxides, polyanion, cation disordered rock‐salt oxides and conversion materials. Particular emphasis is given to the general reaction and degradation mechanisms during the operation as well as the main challenges and strategies to overcome the drawbacks of these materials. 相似文献
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锂离子混合型电容器兼有锂离子电池和超级电容器的优点,在电化学储能领域具有广泛的应用前景. 但其产业化仍存在一系列的基础及工艺方面的问题,具体包括器件结构设计、电极材料筛选、预嵌锂工艺和电解液与电极的界面等. 本文结合作者课题组的研究工作介绍了近年来高能量密度的锂离子混合型电容器的研究进展,内容涉及锂离子电容器正/负极材料的筛选、预嵌锂工艺的优化、内并联结构的锂离子电池型超级电容器复合正极组成材料的调控、隔膜的选择、电解液的组成、以及器件的高/低温性能,分析了锂离子电容器的容量衰减机制,探讨了锂离子电池型超级电容器的储能机制,提出了未来对高能量密度的锂离子混合型电容器研究的展望. 相似文献
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锂离子电池有机电解液材料研究进展 总被引:4,自引:0,他引:4
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。 相似文献
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锂离子电池正极材料正在向着高比能量、长寿命、低成本、环境友好的方向发展,而具有橄榄石结构的LiFePO4正极材料以其结构稳定、成本低、无污染等优点成为21世纪最理想的绿色电源,但自身也存在缺点。综述了锂离子电池正极材料LiFePO4的研究进展。系统地阐述了LiFePO4的晶体结构特征及性能、多种合成方法以及掺杂多种导电材料和控制晶体生长制备纳米粉体对材料性能的影响。对该材料的应用前景进行了展望,并提出了下一步可能的研究趋势。 相似文献
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Research into materials displaying oxide ion conductivity is attracting considerable attention due to their potential technological applications in devices such as Solid Oxide Fuel Cells. In this paper, recent work on apatite-type oxide ion conductors is reviewed, showing that a wide range of cation substitutions are possible, due to the flexibility of the apatite structure in accommodating a range of ion sizes. The conductivity studies on these doped samples show that to achieve high oxide ion conduction, non-stoichiometry in terms of cation vacancies and/or oxygen excess is required, with the latter resulting in the highest conductivities. In contrast to most common oxide ion conductors, e.g. perovskite and fluorite in which oxide ion conduction proceeds via oxygen vacancies, the research on these apatite systems suggests that the conductivity involves interstitial oxide ions. With further optimization of these materials, particularly in terms of the Ge-containing systems, significant improvements in conductivity are likely, leading to the very real possibility of the application of apatite-type electrolytes in fuel cell and other applications. 相似文献
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Improving the preparation technology and electrochemical performance of cathode materials for lithium ion batteries is a current major focus of research and development in the areas of materials, power sources and chemistry. Sol-gel methods are promising candidates to prepare cathode materials owing to their evident advantages over traditional methods. In this paper, the latest progress on the preparation of cathode materials such as lithium cobalt oxides, lithium nickel oxides, lithium manganese oxides, vanadium oxides and other compounds by sol-gel methods is reviewed, and further directions are pointed out. The prepared products provide better electrochemical performance, including reversible capacity, cycling behavior and rate capability in comparison with those from traditional solid-state reactions. The main reasons are due to the following several factors: homogeneous mixing at the atomic or molecular level, lower synthesis temperature, shorter heating time, better crystallinity, uniform particle distribution and smaller particle size at the nanometer level. As a result, the structural stability of the cathode materials and lithium intercalation and deintercalation behavior are much improved. These methods can also be used to prepare novel types of cathode materials such as nanowires of LiCoO2 and nanotubes of V2O5, which cannot be easily obtained by traditional methods. With further development and application of sol-gel methods, better and new cathode materials will become available and the advance of lithium ion batteries will be greatly promoted. 相似文献