锂离子电池容量衰减机理和副反应-翻译(个人翻译的外文文献)

1、锂离子电池容量衰减机理和副反应-翻译(个人翻译的外文文献) Capacity Fade Mechanisms and Side Reactions in Lithium-Ion Batteries 锂离子电池容量衰减机机理和副反应 Pankaj Arorat and Ralph E. White* 作者：Pankaj Arorat and Ralph E. White* Center For Electrochemical Engineering, Department of Chemical Engineering, University of South Carolina,Columbia

2、, South Carolina 29208, USA 美国，南卡罗来纳，年哥伦比亚29208，南卡罗来纳大学，化学工程系，中 心电化学工程 ABSTRACT 摘要 The capacity of a lithium-ion battery decreases 锂离子电池容量随着循环during cycling. This capacity loss or fade occurs due to 衰减。容量损失或者衰减的发several different mechanisms which are due to or are 生主要是由于以下几种反应机associated with unwant

3、ed side reactions that occur in these 理，这些机理起因于或者关联batteries. These reactions occur during overcharge or 于一些我们不希望发生在电池overdischarge and cause electrolyte decomposition, passive 里的副反应。这些反应发生在film formation, active material dissolution, and other 过充或者过放中，导致了电解phenomena. These capacity loss mechanisms

4、are not 液分解、钝化膜的形成、活性included in the present lithium-ion battery mathematical 物质溶解和其他现象形成。这models available in the open literature. Consequently, these 些容量损失机理并没有包含在models cannot be used to predict cell performance during 目前我们可接触到的公开的锂cycling and under abuse conditions. This article presents a 离子电池数

5、学模型中。因此，review of the current literature on capacity fade 这些模型并不能用在预测电池mechanisms and attempts to describe the information 循环或者滥用条件下的电化学needed and the directions that may be taken to include these 行为。这篇文章提出了当前锂mechanisms in advanced lithium-ion battery models. Introduction 离子电池容量衰减机理的观点，并且试图描述我们需要的信

6、息和方向，这些信息和方向有可能被引入先进的锂离子电池模型的机理中。 前言 The typical lithium-ion cell (Fig. 1) is made up of a 典型的锂离子电池主要由coke or graphite negative electrode, an electrolyte which 以下三大部分组成：碳(石墨）serves as an ionic path between electrodes and separates the 负极；电解液，主要提供锂离two materials, and a metal oxide (such as LiCoO2, 子传

7、送通道并且分隔开两种材LiMn2O4, or LiNiO2) positive electrode. This secondary 料；过渡金属氧化物正极材料(rechargeable) lithium-ion cell has been commercialized （例如LiCoO2、LiMn2O4或only recently.Batteries based on this concept have reached 者LiNiO2）。这种二次电池最the consumer market, and lithium-ion electric vehicle batteries are unde

8、r study in industry.The lithium-ion battery market has been in a period of tremendous growth ever since Sony introduced the first commercial cell in 1990.With energy density exceeding 130 Wh/kg (e.g., Matsushita CGR 17500) and cycle life of more than 1000 cycles (e.g., Sony 18650) in many cases, the

9、 lithium-ion battery system has become increasingly popular in applicationssuch as cellular phones, portable computers, and camcorders.As more lithium-ion battery manufacturers enter the market and new materials are developed,cost reduction should spur growth in new applications. Several manufacture

10、rs such as Sony Corporation, Sanyo Electric Company, Matsushita Electric Industrial Company, Moli Energy Limited, and A&T Battery Corporation have started manufacturing lithium-ion batteries for cellular phones and laptop computers. Yoda1 has considered this advancement and described a future ba

11、ttery society in which the lithium-ion battery plays a dominant role. Several mathematical models of these lithium-ion 近已经商业化。这种理念下的电池已经进入消费市场。在工业上，交通工具使用的动力电池已经在研究。自从1990年，索尼首次引进商业化电池，锂离子电池市场在一段时期内取得了巨大增长。在许多条件下，锂离子电池的体积能量密度超过130Wh/kg，循环次数超过1000次，锂离子电池体系在手机、笔记本电脑、便携式摄像机的使用越来越普遍。随着越来越多的电池制造商进入市场，新材料

12、得到发展、成本降低加速了电池的新应用。一部分制造商例如索尼、三洋、松下、Moli能源、A&T电池公司已经开始制作锂离子电池用于移动电话和掌上电脑。Yoda 已经考虑到这些进步并且描述了一个未来的电池社会，在这个社会里锂离子电池扮演非常重要的角色。 已经有一部分锂离子电池的数学模型被出版。不幸的是， cells have been published. Unfortunately, none of these 他们的模型里所描述锂离子电models include capacity fade processes explicitly in their 池的行为中，没有一种模型明mathe

13、matical description of battery behavior. The objective 确的描述容量衰减过程。他们of the present work is to review the current understanding 的主要目的是回顾现有容量衰of the mechanisms of capacity fade in lithium-ion batteries. 减机理模型的相关理解认识。Advances in modeling lithium-ion cells must result from 要建立新模型，必须建立在对improvements in t

14、he fundamental understanding of these 上述这些基础过程的充分理解processes and the collection of relevant experimental data. Some of the processes that are known to lead to capacity fade in lithium-ion cells are lithium deposition (overcharge conditions), electrolyte decomposition, active material dissolution, ph

15、ase changes in the insertion electrode materials, and passive film formation over the electrode and current collector surfaces. Quantifying these degradation processes will improve the predictive capability of battery models ultimately leading to less expensive and higher quality batteries. Signific

16、ant improvements are required in performance standards such as energy density and cycle life, while maintaining high environmental, safety, and cost standards. Such progress will require considerable advances in our understanding of electrode and electrolyte materials, and the fundamental physical a

17、nd chemical processes that lead to capacity loss and resistance increase in commercial lithium-ion batteries. The process of developing mathematical models for lithium ion cells that contain these capacity fade processes not only provides a tool for battery design but also provides a means of unders

18、tanding better how those processes occur. 和收集整合相关数据的的基础上。 大家所知的导致容量衰减的一些过程是锂沉积（过充）、电解液分解、活性物质溶解、插入电极材料的相变，电极和集流体表面钝化膜形成；定量的分析这些退化反应过程将提高电池模型预测能力，最终我们会设计出更便宜质量更好的电池。在电池能量密度、循环性能等方面需要有重大的提升，尽管我们已经达到了环境友好、成本低的标准。取得这些改进，需要我们对电解液、电极材料、以及导致锂离子电池容量衰减和电阻增加的物理化学反应的基本原理的最新的理论知识有足够的了解。锂离子电池容量衰减模型的发展不仅提供了设计电池的工

19、具并且提供了这些过程如何发生的思维方式。 Present Lithium-Ion Battery Models The development of a detailed mathematical model 目前锂电池模型 精细的数学模型的发展对 is important to the design and optimization of lithium 电池后续设计和优化非常重要secondary cells and critical in their scale-up. West developed a pseudo two-dimensional model of a single p

20、orous insertion electrode accounting for transport in the solution phase for a binary electrolyte with constant physical properties and diffusion of lithium ions into the cylindrical electrode particles. The insertion process was assumed to be diffusion limited, and hence charge-transfer resistance

21、at the interface between electrolyte and active material was neglected. Later Mao and White developed a similar model with the addition of a separator adjacent to the porous insertion electrode. These models cover only a single porous electrode; thus, they do not have the advantages of a full-cell-s

22、andwich model for the treatment of complex, interacting phenomena between the cell layers. These models confine themselves to treating insertion into TiS2 with the kinetics for the insertion process assumed to be infinitely fast. Spotnitz accounted for electrode kinetics in their model for discharge

23、 of the TiS2, intercalation cathode. The galvanostatic charge and discharge of a lithium metal/solid polymer separator/insertion positive electrode 并且对电池模型规模扩充非常关键。West 提出了类似二维多孔电极模型，该模型解释了具有稳定物理性能的二元电解质的迁移和锂离子扩散到圆柱形的电极；假定嵌入过程的扩散是有限的，因此电解质和活性物质界面的电荷转移阻抗被忽略。随后，Mao和White提出了一个类似的模型， 但是增加了一个多孔电极的分割器。这些模

24、型仅仅覆盖了一个单一的电极；因此，它们并没有优势处理复杂“三明治”型的电池模型里正负两个电极之间复杂的相互作用的现象。这个模型限制了它自己本身，因为在分析锂离子嵌入TiS2的过程的动力学，模型假定嵌入行为是非常快。Spotnitz解释了插入型正极TiS2放电过程中电极的电化学动力学。 Doyle根据浓溶液理论建 立了金属锂负极/固体聚合物 cell was modeled using concentrated-solution theory by 隔膜/嵌入式正极的恒流充放Doyle. The model is general enough to include a wide range 电模

25、型。这是个通用模型，包of separator materials, lithium salts, and composite 括（正负极）分离材料、锂盐、insertion electrodes. Concentrated-solution theory is used 复合嵌入式电极。浓溶液理论to describe the transport processes, as it has been concluded 用来描述传导过程，因为已经that ion pairing and ion association are very important in 得出结论：离子配对和交联在sol

26、id polymer electrolytes. This approach also provides 固体聚合物电解质中非常重advantages over dilute solution theory to account for volume changes. Butler-Volmer-type kinetic expressions were used in this model to account for the kinetics of the charge-transfer processes at each electrode. The positive electrode

27、 insertion process was described using Picks law with a constant lithium diffusion coefficient in the active material. The volume changes in the system and film formation at the lithium/polymer interface were neglected and a very simplistic case of constant electrode film resistances was considered.

28、 Long-term degradation of the cell due to irreversible reactions (side reactions) or loss of interfacial contact is not predictable using this model. Fuller developed a general model for lithium ion insertion cells that can be applied to any pair of lithium- ion insertion electrodes and any binary e

29、lectrolyte system given the requisite physical property data. Fuller work demonstrated the importance of knowing the dependence of the open-circuit potential on the state of charge for the insertion materials used in lithium-ion cells. The slopes of these curves control the current distribution insi

30、de the porous electrodes, with more sloped open-circuit potential functions leading to more uniform current distributions and 要。这种方法也为体积变化提供了稀浓度理论；这个模型中使用Butler-Volmer-type 动力学公式解释每个电极电荷转移的过程。正极锂离子嵌入过程采用Picks 定律描述，锂离子以恒定速率在活性物质中扩散迁移。在锂/聚合物界面的系统和钝化膜的形成过程中，体积变化忽略不计，但是考虑到一个简化了的恒定的电极界面膜阻抗。该模型不能预测电池长久的退化

31、是由于由于不可逆反应（副反应）或接触面损失。 Fuller 提出了一个普遍的锂离子电池模型，该模型可以应用于任何一对锂离子嵌入式电极和二元电解质体系，并给出必要物理性能参数的。Fuller的模型说明了解锂离子电池嵌入式材料充电状态对开路依赖非常重要。这些曲线的斜率控制了多孔电极材料内部电流分布，开路电压方程曲线的斜率 hence better utilization of active material. Optimization 越高，电流分布越均一，因此studies were carried out for the Bellcore plastic lithium-ion 活性物质利用率

32、更高。Bellcoresystem. The model was also used to predict the effects of 通信研究所做了一些塑料锂离relaxation time on multiple charge-discharge cycles and on 子电池体系的优化研究。 这些peak power. 模型也用来预测松弛时间对多个充电放电周期和峰值功率的影响。 Doyle modified the dual lithium-ion model to include film resistances on both electrodes and made direc

33、t comparisons with experimental cell data for the LiC6-LiPF6, ethylene carbonate/dimethyl carbonate (EC/ DMC), Kynar FLEX-ILiyMn2O4 system. Comparisons between data and the numerical simulations suggested that there is additional resistance present in the system not predicted by present models. The

34、discharge performance of the cells was described satisfactorily by including either a film resistance on the electrode particles or by contact resistances between the cell layers or current-collector interfaces. One emphasis of this work was in the use of the battery model for the design and optimiz

35、ation of the cell for particular applications using simulated Ragone plots. Thermal modeling is very important for lithium batteries because heat produced during discharge may cause either irreversible side reactions or melting of Doyle改进了双电极模 型，包含了双电极的界面阻抗，对比了LiC6-LiPF6（碳酸乙烯酯/碳酸二甲酯（EC / DMC），聚偏氟乙烯-

36、LiyMn2O4 体系的实验数据。对比的实验数据和和拟合数据表明体系还有目前电池模型不能预测稍微额外的阻抗存在。电池的放电行为描述比较满意，包括电极材料颗粒表面的膜阻抗，电池电极层之间以及电极和接流体之间的接触阻抗。这项工作的一个重点是为特殊用途的的 Ragone 模块电池模型的设计和优化的运用。 电池热建模对锂离子电池 非常重要，因为放电过程中产生的热量可能引起不可逆的化 metallic lithium, Chen and Evans carried out a thermal 学副反应或者熔融的金属锂，analysts of lithiumion batteries during cha

37、rge-discharge 陈和Evans利用能量守恒进行and thermal runaway using an energy balance and a 了锂离子电池充放电过程的热simplified description of the electrochemical behavior of 分析实验以及热散失实验，并the system. Their analysis of heat transport and the 且简单描述了体系的电化学行existence of highly localized heat sources due to battery 为。他们对热传递以及局部高

38、abuse indicated that localized heating may raise the battery 热量来源的分析，表明局部高temperature very quickly to the thermal runaway onset temperature, above which it may keep increasing rapidly due to exothermic side reactions triggered at high temperature. Pals and Newman developed a model to predict the the

39、rmal behavior of lithium metal-solid polymer electrolyte cells and cell stacks.This model coupled an integrated energy balance to a fullcell- sandwich model of the electrochemical behavior of the cells. Both of these models emphasized the importance of considerations of heat removal and thermal cont

40、rol in lithium polymer battery systems. Verbrugge and Koch developed a mathematical model for lithium intercalation processes associated with a cylindrical carbon microfiber. They characterized and modeled the lithium intercalation process in single-fiber carbon microelectrodes including transport p

41、rocesses in both phases and the kinetics of charge transfer at the interface. The primary purpose of the model was to predict the potential as a function of fractional occupancy of intercalated lithium. The overcharge protection for a Li/TiS2 cell using redox additives has been theoretically analyze

42、d in terms of a finite linear diffusion model by Narayanan . 热引起电池温度很快升高到热失控温度，由于放热副反应发生，高于这个温度后，电池温度上升更快。Pals 和 Newman提出一个模型预测聚合物电解质电池和电池组的热行为。这个模型联合了一三明治模型电池的热平衡的电化学行为。这两个模型强调了热传递和热控制在聚合物锂离子电池体系中的重要性。 Verbrugge和Koch 提出了一个与圆柱型碳纤维电极的 锂离子嵌入过程的数学模型。他们模拟锂离子嵌入单纤维碳电极的过程，包括锂离子在两相的迁移和界面点和传导的动力学。这个模型最初的目的是为

43、了预测电势与嵌入锂的函数关系。Narayanan采用线性扩散模型对Li/TiS的过充保护，电池的氧化还原添加剂进行了理论分析。 Darling and Newman modeled a porous Darling和 Newman建立intercalation cathode with two characteristic 了具多孔电极以及有两个粒度particle sizes.They reported that electrodes with a 特征分布的电池模型。他们电particle size distribution show modestly inferior 极的颗粒粒度只有一

44、个分布的capacity-rate behavior and relaxation on open 电池显示了较差的倍率性能，circuit is substantially faster when the particles are uniformly sized. Nagarajan modeled the effect of particle size distribution on the intercalation electrode behavior during discharge based on packing theory. They observed that durin

45、g pulse discharge, an electrode consisting of a binary mixture displays higher discharge capacity than an electrode consisting of single sized particles. The current from the smaller particles reverses direction during the rest period which cannot be observed in the case of an electrode comprised of

46、 the same-sized particles. Recently Darling and Newman made a first attempt to model side reactions in lithium batteries by incorporating a solvent oxidation side reaction into a lithium-ion battery model, Even though a simplified treatment of the oxidation reaction was used, their model was able to

47、 make several interesting conclusions about self-discharge processes in these cells and their impact on positive electrode state-of-charge。 A number of models having varying degrees of sophistication have been developed for lithium rechargeable batteries. For the most part, these models consider the

48、 ideal behavior of the systems, neglecting the phenomena that lead to losses in 有大小分布的开路电压的弛豫时间更快。Nagarajan 以包装理论为基础，建立模型说明了颗粒分布对嵌入电极的放电的影响。他们观察到在脉冲放电的过程，二元混合物电极的放点容量比一个单一粒子组成的电极的容量更高。小颗粒的电流调转方向，但是在单一粒度的电极中并没有观察到。最近， Darling和Newman首次模拟电池的副反应，通过引入一种溶剂的氧化还原副反应到电池模型中。尽管氧化还原简单处理，他们的模型仍然能够得出自放电过程的结论，以及它们

49、对正极充电的影响。 许多复杂程度不同的模型已经被被提出来描述可充电锂离子电池。大多数情况下，这些模型考虑这个体系的理想行为，忽略了在充放电循环过程 capacity and rate capability during repeated 中导致容量和倍率性能损失的charge-discharge cycles. Fundamental models of 现象。这些现象的基础模型比these latter phenomena are less common because 较少见，因为这些过程更加不these processes are not as well understood. Also

50、, 容易理解。同样，锂离子电池models of failure modes in batteries do not usually 的衰败模型一般不适用于较为have general applicability to a wide range of 广泛的体系。然而，在安全和systems. However, the importance of these 电池能效方面的现象的重要性phenomena in the safe and efficient operation of high-energy lithium-ion batteries requires that they be i

51、n corporated into future battery models。 Capacily Fading Phenomenon Side reactions and degradation processes in lithium-ion batteries may cause a number of undesirable effects leading to capacity loss. Johnson and White have shown that the capacities of commercial lithium-ion cells fade by ca.10-40%

52、 during the first 450 cycles.A flow chart describing many of the processes leading to capacity fade is shown in Fig. 2. In Fig. 3, the capacity fade processes are shown on half-cell discharge curves. This gives a clearer picture of the processes by demonstrating where each is expected to manifest it

53、self during operation of the battery Below, we discuss each of these processes in some detail, after first discussing the general topic of capacity balance. Capacity Balancing in Lithium-Ion Cells Lithium-ion cells operate by cycling lithium ions between two insertion electrode hosts having differen

54、t insertion energies.For optimum 需要与未来的电池模型结合。 容量衰减现象 锂离子电池发生的副反应和衰败过程可能引起一系列会导致容量损失的不希望发生的结果。Johnson和 White已经证明商业锂离子电池容量在开始的450次循环衰减10-40%，导致容量衰减的一些过程的流程图表如图2所示；图3 中，显示了半电池放电曲线衰减过程。这个图清晰的演示了每个过程，每个预期的电池运行的过程。在讨论了容量平衡的主题之后，我们会讨论了每个过程的细节。 锂离子电池中容量的平衡 锂离子电池的运行通过锂离子在两个嵌入式电极之间循环，这两个电极嵌入锂的能量 performance,

55、 the ratio of the lithium-ion capacities 不同。为了优化性能，两种电of the two host materials should be balanced. 极的锂离子容量比例应该保持Capacity balancing refers to the optimization of the 平衡。容量平衡是指在循环稳mass loading in the two electrodes to achieve the 定的条件下，正负极处的物质maximum capacity (or energy) from the battery 量必须获得最高的容量（或

56、者under conditions of steady cycling. Due to the 能量）。这个题目的实际意义非practical importance of this subject for maximizing 常重要，如同不平衡电池的安cell performance, as well as the safety implications with poorly balanced cells, this subject has been discussed in the literature by several authors. The condition for bala

57、nced capacities in a lithium-ion cell can be written in terms of a ratio of active masses in the electrodes. Written as a ratio of positive to negative electrode masses, this expression is This equation says that the desired mass ratio depends on the relative coulombic capacities of the two electrodes (C is in units of mAh/g) and the amount of cyclable lithium in each. The cyclable lithium is quantified in terms of the range of lithium stoichiometry in the insertion electrode that can be cycled reversibly, with the notation that x refers to the r