Fundamental scientific aspects of lithium batteries (Ⅷ)----Anode electrode materials

锂离子电池的成功商业化,起始于石油焦负极材料.负极作为锂离子电池必不可少的关键材料,目前主要集中在碳,钛酸锂以及硅基等合金类负极,采用传统的碳负极可以基本满足消费电子,动力电池,储能电池的要求,采用钛酸锂可以满足高功率密度,长循环寿命的要求,采用合金类负极材料有望进一步提高能量密度.本文小结了目前广泛使用和正在研究的锂离子电池负极材料的性能特点,讨论了下一代锂离子电池负极材料的研究和发展状况.     

Role of carbon host lattices in Li-ion intercalation/de-intercalation processes

Despite considerable efforts to find other substituents, carbon still remains the only commercially viable negative electrode (anode) material for Li-on batteries. Present work aimed at understanding, characterising and improving the performance of carbon anode materials is reviewed. A brief historical background of developments in carbon host lattices is presented. A wide range of carbon materials from amorphous to highly oriented graphitic materials and the techniques employed in characterisation of the lithium insertion/de-insertion process are outlined. Fundamental investigations of the electrochemical process on natural graphite, as well as highly oriented pyrolitic graphite materials, are then comprehensively reviewed. The problems and prospects of different hard carbon materials which increased battery capacity are then discussed. A variety of new carbon materials and carbon-based composites are also introduced. The critical review ends with an overview of the present status of carbon materials and their role in Li-ion battery systems for different potential applications.     

Graft copolymer-based lithium-ion battery for high-temperature operation

The use of conventional lithium-ion batteries in high temperature applications (>50 °C) is currently inhibited by the high reactivity and volatility of liquid electrolytes. Solvent-free, solid-state polymer electrolytes allow for safe and stable operation of lithium-ion batteries, even at elevated temperatures. Recent advances in polymer synthesis have led to the development of novel materials that exhibit solid-like mechanical behavior while providing the ionic conductivities approaching that of liquid electrolytes. Here we report the successful charge and discharge cycling of a graft copolymer electrolyte (GCE)-based lithium-ion battery at temperatures up to 120 °C. The GCE consists of poly(oxyethylene) methacrylate-g-poly(dimethyl siloxane) (POEM-g-PDMS) doped with lithium triflate. Using electrochemical impedance spectroscopy (EIS), we analyze the temperature stability and cycling behavior of GCE-based lithium-ion batteries comprised of a LiFePO₄ cathode, a metallic lithium anode, and an electrolyte consisting of a 20-μm-thick layer of lithium triflate-doped POEM-g-PDMS. Our results demonstrate the great potential of GCE-based Li-ion batteries for high-temperature applications.     

Reviews of selected 100 recent papers for lithium batteries(Apr. 1,2013 to May 31,2013)

该文是一篇近两个月的锂电池文献评述,我们以"lithium"和"batter*"为关键词检索了Web of Science从2013年4月1日至2013年5月31日上线的锂电池研究论文,共有855篇,选择其中100篇加以评论.层状氧化物正极材料的热稳定性,循环过程中的结构相变以及产气问题受到人们关注,高电压的尖晶石结构LiNi0.5M1.5O4在高压下与电解液的匹配以及添加剂的使用也受到人们较多的关注.高容量的Si基负极材料一直是研究的热点,本期碳材料负极也出现了几篇有深度的研究论文.固态聚合物电解质和无机电解质,液态电解质的成膜添加剂均有研究.具有高能量密度的新体系,锂硫电池的研究论文多于锂空气电池的.除了这些以材料为主的研究之外,针对电池安全和电池应用的研究论文也在逐渐增多,这对电池技术的创新将产生促进作用.     

Challenges for rechargeable batteries

Strategies for Li-ion batteries that are based on lithium-insertion compounds as cathodes are limited by the capacities of the cathode materials and by the safe charging rates for Li transport across a passivating SEI layer on a carbon-based anode. With these strategies, it is difficult to meet the commercial constraints on Li-ion batteries for plug-in-hybrid and all-electric vehicles as well as those for stationary electrical energy storage (EES) in a grid.Existing alternative strategies include a gaseous O₂ electrode in a Li/air battery and a solid sulfur (S₈) cathode in a Li/S battery. We compare the projected energy densities and EES efficiencies of these cells with those of a third alternative, a Li/Fe(III)/Fe(II) cell containing a redox couple in an aqueous solution as the cathode. Preliminary measurements indicate proof of concept, but implementation of this strategy requires identification of a suitable Li⁺-ion electrolyte.     

Effect of entropy change of lithium intercalation in cathodes and anodes on Li-ion battery thermal management

The entropy changes (ΔS) in various cathode and anode materials, as well as in complete Li-ion batteries, were measured using an electrochemical thermodynamic measurement system (ETMS). LiCoO₂ has a much larger entropy change than electrodes based on LiNi_xCo_yMn_zO₂ and LiFePO₄, while lithium titanate based anodes have lower entropy change compared to graphite anodes. The reversible heat generation rate was found to be a significant portion of the total heat generation rate. The appropriate combinations of cathode and anode were investigated to minimize reversible heat generation rate across the 0-100% state of charge (SOC) range. In addition to screening for battery electrode materials with low reversible heat, the techniques described in this paper can be a useful engineering tool for battery thermal management in stationary and transportation applications.     

Improved lithium-ion batteries and their communication with hydrogen power

Self-contained power supplies and energy storage continue to improve. The criteria that determine their development include efficiency, safety, adaptability, modifiability, and a number of others. In this work, one of the ways to improve the lithium-ion battery by using a new negative electrode is considered. The possibilities of applicability of the improved lithium-ion battery are discussed, its advantages and disadvantages in relation to a hydrogen fuel cell and power sources using hydrogen fuel are considered. The study of the functioning of the new anode, the material of which is a two-layer silicene on a nickel substrate, is carried out at the atomic level. Improvement of the anode characteristics can be achieved by subjecting it to the neutron doping. Li-ion batteries with an improved anode will have higher charging capacity and power, faster charging and improved safety.     

Fundamental scientific aspects of lithium batteries(I)--Thermodynamic calculations of theoretical energy densities of chemical energy storage systems

本文主要讨论电池的能量密度.基于热力学数据,根据能斯特方程,可以计算不同电化学反应体系的理论能量储存密度,从而了解化学储能体系理论能量密度的上限,了解哪些体系能够实现更高的能量密度,哪些材料具有更高的电压.     

钛酸锂基锂离子电池及其健康状态研究进展

锂离子电池的高功率密度和高能量密度等特性使其成为电动汽车能源和新能源电网储能的重要载体。功率性能和安全特性是锂离子电池发展的两个主要挑战。钛酸锂Li₄Ti₅O₁₂材料因具有良好的结构稳定性、安全性能、长循环寿命、高功率特性和高低温放电性能,被认为是锂电池负极材料的良好备选。综述了以钛酸锂材料为负极的锂离子电池的相关工作,介绍了钛酸锂材料的结构、电化学特性、制备方法和作为电池负极材料面临的主要问题,重点介绍了钛酸锂负极电池的全电池性能和健康状态研究等方面。     

Constructing Janus SnSSe and graphene heterostructures as promising anode materials for Li-ion batteries

Developing efficient anode materials for Li-ion batteries is becoming increasingly important but is still challenging to collect relevant information about their adsorption and diffusion. Herein, by means of density functional theory (DFT) computations, the Janus SnSSe, and graphene van der Waals heterostructures (ie, SSnSe/G and SeSnS/G) are systematically investigated by first principles calculations, aiming at constructing promising anode materials for Li-ion batteries (LIBs). The results have demonstrated that the SnSSe/G heterostructures exhibits a semimetal-to-metal transition after incorporating Li, indicating enhanced conductivity compared to monolayer Janus SnSSe or graphene. Moreover, the SnSSe/G heterostructures can maintain favorable structural stability and ultrahigh stiffness well after applying the strain or adsorption of lithium atoms, thereby ensuring the pulverization resistance. In addition, the energy barriers of Li atoms diffusion are very low, which are expected to achieve a fast charge/discharge rate. Meanwhile, the estimated storage capacity of Li on SnSSe/G heterostructures could achieve 472.66 mA h g^?1, which greatly improves the storage capacity. These interesting results show that Janus SnSSe/G heterostructures could be used as excellent anode materials for LIBs.     

Review on state of health estimation of retired lithium-ion batteries

由于电池组中电池单体之间存在性能差异,退役锂离子电池在投入梯次利用前需要借助健康状态（SOH）评估技术进行电池单体的分类与配组。健康状态评估系统的构建涉及电池建模、电池测试、数据处理、算法开发等各种技术问题。目前通过基于模型的参数识别与直接提取健康因子是构建SOH评估体系的两种主要思路。在电池模型的简化、测试工况的设计、健康因子的选择和算法的应用与优化等方面已经有了很多研究。如何在缩短电池测试时间的同时提高评估系统的泛化能力是目前该研究领域的主要问题,这些问题的解决对于SOH评估系统真正在梯次利用锂离子电池的产业化中发挥作用至关重要。在未来的研究中通过优化测试工况和数据融合等技术,有望开发出性能更好的SOH评估系统。     

Recent progress of electrode materials for room-temperature sodium-ion stationary batteries

随着风能、太阳能等可再生能源的不断发展,储能作为影响其发展的关键技术越来越受到人们的关注。在储能领域,锂离子电池以高能量密度、长循环寿命、高电压等诸多优点在电子领域已得到广泛的应用,并成为未来电动汽车动力电池的最佳选择。但因锂资源储量有限、分布不均匀,而且原材料成本比较高,所以锂离子电池在电网大规模储能方面的应用遇到了瓶颈。与锂相比,钠不但具有与锂相似的物理化学性质,更具有资源丰富、分布广泛、原料成本低廉等优势。近些年室温钠离子电池再次引起了人们的研究兴趣,特别是在电网储能方面表现出极大的应用潜力。虽然目前已报道了多种钠离子电池电极材料,但大都离实用化以及进一步产业化尚有一定的距离。本文重点介绍一些性能较为突出的室温钠离子电池电极材料,并指出要实现钠离子电池的产业化,需要开发空气中稳定、高安全、高容量、高倍率、循环稳定、低成本的新型正、负极材料。     

Use of lithium-ion batteries in electric vehicles

An account is given of the lithium-ion (Li-ion) battery pack used in the Northern Territory University's solar car, Fuji Xerox Desert Rose, which competed in the 1999 World Solar Challenge (WSC). The reasons for the choice of Li-ion batteries over silver–zinc batteries are outlined, and the construction techniques used, the management of the batteries, and the battery protection boards are described. Data from both pre-race trialling and race telemetry, and an analysis of both the coulombic and the energy efficiencies of the battery are presented. It is concluded that Li-ion batteries show a real advantage over other commercially available batteries for traction applications of this kind.     

Investigating electrical contact resistance losses in lithium-ion battery assemblies for hybrid and electric vehicles

Lithium-ion (Li-ion) batteries are favored in hybrid-electric vehicles and electric vehicles for their outstanding power characteristics. In this paper the energy loss due to electrical contact resistance (ECR) at the interface of electrodes and current-collector bars in Li-ion battery assemblies is investigated for the first time. ECR is a direct result of contact surface imperfections, i.e., roughness and out-of-flatness, and acts as an ohmic resistance at the electrode-collector joints. A custom-designed testbed is developed to conduct a systematic experimental study. ECR is measured at separable bolted electrode connections of a sample Li-ion battery, and a straightforward analysis to evaluate the relevant energy loss is presented. Through the experiments, it is observed that ECR is an important issue in energy management of Li-ion batteries. Effects of surface imperfection, contact pressure, joint type, collector bar material, and interfacial materials on ECR are highlighted. The obtained data show that in the considered Li-ion battery, the energy loss due to ECR can be as high as 20% of the total energy flow in and out of the battery under normal operating conditions. However, ECR loss can be reduced to 6% when proper joint pressure and/or surface treatment are used. A poor connection at the electrode-collector interface can lead to a significant battery energy loss as heat generated at the interface. Consequently, a heat flow can be initiated from the electrodes towards the internal battery structure, which results in a considerable temperature increase and onset of thermal runaway. At sever conditions, heat generation due to ECR might cause serious safety issues, sparks, and even melting of the electrodes.     

High stability and superior rate capability of three-dimensional hierarchical SnS2 microspheres as anode material in lithium ion batteries

3D hierarchical SnS₂ microspheres have been designed and fabricated via a one-pot biomolecule-assisted hydrothermal method. When used as anode material in rechargeable Li-ion batteries, the as-formed SnS₂ microspheres self-assembled by layered nanosheets, show high lithium storage capacity, long-term cycling stability and superior rate capability. After charge-discharge for 100 cycles, the remaining discharge capacities are kept as high as 570.3, 486.2, and 264 mAh g⁻¹ at 1C (0.65 A g⁻¹), 5C, and 10C rate, respectively. Such outstanding performance of these SnS₂ microspheres is ascribed to their unique 3D hierarchical structures. The new charge-discharge mechanism of 3D SnS₂ microsphere as anode in Li-ion battery is further revealed.     

Materials design and its implementation for flexible Li-S batteries

随着具有变形功能的移动电子设备的出现和发展,具有更高能量密度的柔性锂硫电池受到越来越多的重视。本文总结了柔性锂硫电池关键材料的发展现状,并对柔性锂硫电池的未来发展方向进行了展望。锂硫电池柔性化的主要难点在于其关键材料的变形设计,通过将硫正极附着于碳纳米管和石墨烯薄膜、聚合物等柔性基底上,利用基底提供变形支撑,能够制备出一体化的复合锂硫电池正极。相对于可变形正极材料,锂金属负极的柔性化具有更大的挑战。未来通过发展新型的锂金属担载材料或采用非金属锂负极,有望实现锂硫电池负极的可变形特征。虽然存在尚待解决的问题很多,柔性锂硫电池经过适当的电化学性能和力学性能改进,将在移动电子领域得到广泛应用。     

Overview and preliminary in orbit behaviour of the lithium-ion batteries used onboard TX-2 satellite

通信技术卫星二号锂离子蓄电池组是我所自主研制的锂离子蓄电池组首次在GEO卫星上应用。卫星对蓄电池组提出了长寿命和高可靠性的技术要求,通过研究分析提出了合理的在轨管理策略和故障隔离技术以满足总体技术要求。同时介绍了通信技术卫星二号锂离子蓄电池组的设计、地面性能测试与考核以及在轨运行验证情况。在轨运行期间,锂离子蓄电池组性能优异,各单体电池之间保持良好的一致性;在轨管理策略合理。遥测数据表明：锂离子蓄电池组在轨运行良好,充分验证了地面设计,为锂离子蓄电池组后续在GEO卫星上的大量应用打下了良好的基础。     

Recent progress in the application of carbon materials to supercapacitors and lead-carbon batteries

新型炭材料是电化学储能领域中非常重要的一类储能材料,目前广泛应用于各种电化学储能器件.本文综述了具有电容特性的高比表面积炭材料在超级电容器与铅炭电池中的应用.采用不同的方法合成具有高比表面积的新型炭材料作为超级电容器电极材料,能够得到较高的比容量.适量高比表面积的炭材料应用于铅酸电池负极,形成铅炭电池,极大地提高了电池的储能特性.论文最后探讨了新型炭材料在超电容以及铅炭电池中应用的发展方向.     

Illustration of experimental,machine learning,and characterization methods for study of performance of Li-ion batteries

The development of fault diagnosis of Li-ion batteries used in electric vehicles is vital. In this perspective, the present work conducted a comprehensive study for the evaluation of coupled and interactive influence of charging ratio, number of cycles, and voltage on the discharge capacity of Li-ion batteries to predict the life of battery. The charging-discharging experimental tests on Li-ion batteries have been performed. The data such as charging ratio, number of cycles, voltage, and discharge capacity of Li-ion batteries are measured. Machine learning approach of neural networks is then applied on the obtained data to compute the effects, normal distribution, parametric analysis, and sensitivity analysis of the input parameters on the capacity of battery. It can be noticed that discharge capacity increased with an increase in full voltage. Further, it has been observed from the sensitivity analysis that the full voltage is most relevant parameters to the capacity of the battery. Additionally, scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) of the electrodes before and after experiments have been performed, to investigate the elemental dissolution due to the charging/discharging cycles. The findings and analysis from the proposed study shall facilitate experts in making decisions on the remaining life and charging capacity of the battery.     

An environmental aircraft battery (EAB)

The Battery Branch of the U.S. Air Force Research Laboratory began the development of an environmental aircraft battery (EAB) to replace existing nickel/cadmium (Ni–Cd) and sealed lead-/acid (SLA) batteries to minimize or eliminate use of environmentally hazardous battery materials by the USAF. A three-phase development contract was awarded in 1996 to replace the cadmium in Ni–Cd batteries with a metal hydride (MH) anode. Designs, materials, space battery technology, and results on commercial and government battery programmes were evaluated in the Phase I, Feasibility Analysis. Bipolar and prismatic designs were selected for Phase II development. Materials and cell test data are presented.