锂离子电池纳米电极材料研究

采用ＸＲＤ，ＴＥＭ方法对纳米相电极材料的结构，形貌进行表征，并用循环伏安法，恒流充放电法对电极材料的嵌锂电化学行为进行研究。结果表明，由于纳米材料的微结构特性使萁 具有优越的嵌锂特性；１）锂离子嵌入电极材料内部的深度小，过程短，具 较大的比表面，有利于采用较大的电流对该电池进行充放电；２）具有较大的嵌锂空间位置，有利于增加电极的锂嵌容量。     

锂离子电池电极材料选择

商用锂离子电池发展至今已有20年,为了满足不同方面的社会需求,人们迫切需要新型锂离子电池电极材料.本文首先简要介绍了锂离子电池的相关知识,随后对多种新型锂离子电池正负极材料的制备、改进方法及电化学性能做了详细介绍,最后对各种电极材料的优缺点进行了简要的总结.本文还对锂离子电池在未来的应用进行了展望,以期待锂离子电池更好...     

核壳结构的锂离子电池材料

核壳结构材料可以实现核与壳功能的复合与互补,近年来核壳结构的设计理念也被引入到锂离子电池材料中。本文综述了纳米/亚微米核壳结构锂离子电池材料的制备方法、电化学性能和结构稳定性等方面的最新研究进展,评述了该类材料存在的问题并展望了其发展前景。商业化的锂离子电池材料还不能满足高能量密度和安全性等多方面的要求,通过合成核与壳功能互补的材料,可望提高材料的综合性能.     

锂离子电池电极材料固体核磁共振研究进展

对于研究材料的结构变化和考察原子所处的化学环境，固体核磁共振技术是一种有效的手段。通过⁶Li和⁷Li核磁共振谱的变化，可以清楚地了解锂离子电池电极材料中Li与邻近金属或碳原子的配位情况及在充放电过程中对应于锂离子嵌/脱过程中材料的结构变化，对于研究电极材料的电化学性能有重要的意义。本文综述了固体NMR技术在研究锂离子电池电极材料的结构及嵌锂机理方面的一些进展。     

摇椅锂离子二次电池及其嵌入式电极材料

本文着重对摇椅锂离子二次电池的工作原理，电池采用的嵌入式电极材料的结构，常见的合成方法，插层反应和电化学性能的研究情况以及应用前景和存在的问题等作一综述。     

锂离子电池有机硫化物电极材料*

有机硫化物电极材料是一类新型高比容量的储能材料,通过S-S键的可逆断裂与键合进行释能与储能,主要应用于锂离子电池的正极。该材料包括有机二硫化物、有机多硫化物和硫化聚合物等。本文综述了有机硫化物电极材料的研究现状,分析了各种材料的优势与不足,并展望了其发展趋势。如何提高现有材料的比容量并改善其循环性能是目前的研究重点。     

磷基锂离子电池电极材料进展

磷基锂离子电池能量密度高、资源丰富、价格低廉,在人们的日常生活中得到了广泛的应用.本文综述近年来磷基锂离子电池电极材料的研究进展以及不同类型电极材料的电化学性能,并对未来的研究方向进行展望.     

纳米薄膜锂离子电池电极材料

本文总结了近年来纳米薄膜锂离子电池电极材料的研究情况,特别是本课题组在这方面的工作进展.我们从纳米颗粒和纳米结构两方面对各种纳米电极材料进行了分类和归纳,对于纳米颗粒组成的薄膜电极材料,除了对传统的锂一金属氧化物(LiMO2,LiMn2O4等)电极材料和聚阴离子型(LiFePO4等)电极材料薄膜化的研究做了介绍之外,着...     

柔性锂离子电池的电极

科技进步使可穿戴设备等便携式电子产品得到了快速发展,柔性电池作为其核心部件,受到越来越多研究者的关注。锂离子电池因具有良好的循环稳定性和较长的使用寿命等优点,成为各类产品的主要电源。为满足电子产品柔性化、微型化发展需求,开发高能量密度的柔性锂离子电池成为亟待解决的问题,作为其关键材料之一的柔性电极是重要的研究方向。本文阐述了柔性锂离子电池电极的研究进展,包括基于自身带有电化学活性的碳材料、Mxene材料的一体化柔性电极,基于非电化学活性的聚合物材料、纺织材料、金属基的一体化柔性电极,以及为满足可穿戴设备可编织和大尺寸形变使用需求的宏观柔性新型电极结构设计,分析并探讨了柔性电极目前存在的问题,以期为未来高能量密度柔性锂离子电池的研究提供新的思路。     

锂离子电池新型树脂碳电极材料的研究

测试分析了碳化处理条件对糠醇树脂碳化产物组成,结构和电化学性能的影响,结果表明：620℃碳化处理的样品出现了明显尖锐的（100）晶面特征衍射峰。同时还发现了（110）和（006）晶面特征衍射峰,表现糠醇树脂是一种较易石墨化的树脂材料,碳化样品比表面积均随着处理温度升高而下降。处理气氛对碳化产物比表面积的影响表现得更为强烈。700℃惰性气氛中碳化处理的样品与还原性气氛中处理的样品相比,比表面积降低了约61．5％,实验结果还发现620℃－1300℃范围内处理的糠醇树脂碳化样品组装的锂离电池都表现出了相对较高的充放电容量,其中700℃碳化处理的样品组装的锂离子电池充放电容量最高,实验结果还表明树脂碳化产物的比表面积是影响电池充放电性能的重要因素,碳化产物的比表面积越大,电池的充放电容量就越高。     

室温钠离子储能电池电极材料结构研究进展

随着风能和太阳能等新能源的大规模发展及未来智能电网的实现,大规模储能系统显得越来越重要.室温钠离子电池以较低的成本再次引起了研究者的兴趣,并成为一种有前途、低成本的储能体系.目前,已提出多种材料可作为钠离子电池的电极材料.一般而言,材料的性质主要由材料的晶体结构决定,本文主要介绍目前提出的多种可行室温钠离子电池电极材料的晶体结构,希望通过总结已有电极材料的晶体结构,对新材料的设计提供指导.     

Carbonyl polymeric electrode materials for metal-ion batteries

This review presents the recent progress in carbonyl polymeric electrode materials for lithium-ion batteries, sodium-ion batteries and magnesiumion batteries. This comprehensive review is expected to be helpful for arousing more interest of organic materials for metal-ion batteries and designing novel battery materials with high performance.     

Vanadium oxide gels as electrode materials for lithium batteries

Electrochemical lithium insertion has been studied in a large number of vanadium oxides with three dimensional framework structure. Several of these oxides have shown high capacities for lithium insertion and good reversibility.Pure solutions of decavanadic acid have shown to undergo spontaneous polycondensation reaction forming sols or gels of highly polymerized vanadium oxides, M _w 10⁶. After dehydration a series of xerogels with varying amounts of water, V₂O₅ · nH₂O, can be obtained. The structure of these xerogels consists of ribbons of corner and edge sharing VO₆ octahedra stabilized by interlayer water molecules. Under ambient conditions the water content corresponds to n=1.8, but this value can be reversibly changed under mild drying conditions.This report deals with the electrochemical insertion of lithium in dried vanadium oxide xerogels, with special regard to the use of these materials as electrodes in rechargeable lithium batteries.     

Methods for enhancing the capacity of electrode materials in low-temperature lithium-ion batteries

Lithium-ion batteries(LIBs) have evolved into the mainstream power source of ene rgy sto rage equipment by reason of their advantages such as high energy density,high power,long cycle life and less pollution.With the expansion of their applications in deep-sea exploration,aerospace and military equipment,special working conditions have placed higher demands on the low-temperature performance of LIBs.However,at low temperatures,the severe polarization and inferior electrochemical activity of electrode materials cause the acute capacity fading upon cycling,which greatly hindered the further development of LIBs.In this review,we summarize the recent important progress of LIBs in low-temperature operations and introduce the key methods and the related action mechanisms for enhancing the capacity of the various cathode and anode materials.It aims to promote the development of high-performance electrode materials and broaden the application range of LIBs.     

Goethite nanorods as anode electrode materials for rechargeable Li-ion batteries

Although various transition metal oxides have been reported to act as low potential Li insertion hosts, the oxyhydroxides have remained unexplored to date. We show here that the hydroxide ions present in transition metal oxyhydroxides do not interfere with the lithium uptake and extraction, permitting very good reversibility of the reduction/oxidation reactions. Goethite (α-FeOOH) nanocrystals can uptake and extract large amount of Li via the conversion reaction mechanism, providing a reversible capacity of 500 mA h g⁻¹ at an average potential of 0.85 V vs. Li/Li⁺. The mechanism was examined using a combination of X-ray diffraction, electron microscopy, and the corresponding selected area electron diffractions (SAEDs). The α-FeOOH is reduced into nanoparticles of metallic Fe⁰ embedded in an amorphous matrix of Li₂O and LiOH in the first discharge; the subsequent cyclings are redox reactions between metallic Fe⁰ and Fe₂O₃ clusters.     

Interconnected sandwich structure carbon/Si-SiO2/carbon nanospheres composite as high performance anode material for lithium-ion batteries

In the present work,an interconnected sandwich carbon/Si-SiO2/carbon nanospheres composite was prepared by template method and carbon thermal vapor deposition（TVD）.The carbon conductive layer can not only efficiently improve the electronic conductivity of Si-based anode,but also play a key role in alleviating the negative effect from huge volume expansion over discharge/charge of Si-based anode.The resulting material delivered a reversible capacity of 1094 mAh/g,and exhibited excellent cycling stability.It kept a reversible capacity of 1050 mAh/g over 200 cycles with a capacity retention of 96%.     

Hydrothermal synthesis of rod-like CoMoO4 and its excellent properties for the anode of lithium-ion batteries

CoMoO₄ has attracted extensive interest as an anode for lithium-ion batteries due to its high theoretical capacity and low cost. Nevertheless, achieving controlled synthesis of CoMoO₄ with definite morphology by simply adjusting a certain synthesis condition is a very meaningful topic. Here, rod-like CoMoO₄ formed by lamellar stacking was successfully synthesized through the control pH value of one-step hydrothermal route, and its excellent electrochemical performance was investigated. The rod-like CoMoO₄ prepared at 190°C and pH = 7 has a high initial discharge capacity of 1,482.8 mAh/g at 200 mA/g. The discharge capacity of 1,041 mAh/g was maintained after 500 cycles, and the capacity retention was 70.2%. The improved electrochemical performance of rod-like CoMoO₄ can be attributed to the rod structures, which could shorten ion diffusion and electronic conduction pathway, provide more efficient charge storage sites, and alleviate the volume changes during Li + intercalation/deintercalation.     

Nano-sized carboxylates as anode materials for rechargeable lithium-ion batteries

Nano-sized caiboxylales Na2C7H3NO4 and Na2C6H2N2O4 were prepared and investigated as anode materials for lithium-ion batteries.Both carboxylates exhibit high reversible capacities around 190 mAh/g above a cut-off voltage of 0.8 V vs.Li＋/Li.potentially improving the safety of the batteries.In addition,good rate performance and long cycle life of these carboxylates make them promising candidates as anode materials for lithium-ion batteries.     

Tin oxalate as a precursor of tin dioxide and electrode materials for lithium-ion batteries

Tin(II) oxalate was studied as a novel precursor for active electrode materials in lithium-ion batteries. The discharge of lithium cells using tin oxalate electrodes takes place by three irreversible steps: tin reduction, forming a lithium oxalate matrix; solvent decomposition to form a passivating layer; and oxalate reduction in a two-electron process. These are followed by reversible alloying of tin with lithium, leading to a maximum discharge of 11 F/mol. Cycling of the cells showed reversible capacities higher than 600 mAh/g during the first five cycles and ca. 200 mAh/g after 50 cycles. Tin oxalate was converted to tin dioxide by thermal decomposition at 450 °C and also by a chemical method by dissolving tin oxalate powder in 33% v/v hydrogen peroxide at room temperature. The ultrafine nature of the tin dioxide powders obtained by this procedure allow their use as electrodes in lithium cells. The best capacity retention during the first five cycles was achieved for a sample heat treated to 250 °C to eliminate surface water. Electronic Publication