锂离子动力电池生热特性分析及其选配

发布时间：2018-03-30 02:07

本文选题：锂离子电池　切入点：热特性　出处：《吉林大学》2014年硕士论文

【摘要】：随着资源短缺和环境污染的日益严重，汽车保有量的不断提高，新能源汽车的研发与推广已经成为国家制定城市发展战略的重要手段。由于城市用车具有日行驶里程相对固定，停车位置比较集中的特点，因此更加有利于纯电动汽车的推广。为了满足纯电动汽车续驶里程，或者为了达到足够的驱动要求及制动能量回收效能，需要车载电池能够保证更多的能量供给，也带来了电池包热管理的难题。由于电池包温度与电池的使用性能与使用寿命息息相关，同时也影响着电池组的可靠性与安全性，研究电池包生热、传热、散热的有关规律，设计合理的电池包结构，研发有效的电池热管理系统变得十分重要。本文分析和总结了国内外电池热管理的研究现状，采用计算流体力学的分析方法进行了电池选型与结构优化，下面介绍论文研究内容。首先对国内外的研究现状进行分析，从锂离子电池反应及生热原理入手，，着重研究了电池组一致性对电池使用性能的影响。通过分析电池容量、内阻与温度之间的关系，得到在保证电池一致性前提下所需要进行温度及温差控制的目标范围。其次研究了锂离子电池生热、传热及散热的基本原理，通过合理简化，利用计算流体力学仿真软件FLUENT得到锂离子电池的热模型，通过Matlab及Advisor以拟合曲线与数组存储的方式获取了恒流充电与循环工况下的生热速率，并通过FLUENT实时调用的方式仿真对比了两种锂离子电池的温度场分布，最终确定选择小容量的锂离子电池并联以获得较低的温升及较小的温差最后对某电池包进行建模，改变其结构参数进行一系列仿真，通过分析不同结构参数下电池包的温度场、压力场及流线分布，总结强制风冷的冷却规律，最终确定楔形通风结构各项结构参数，使其在循环工况条件下一致性保持在98%以上，在快速充电和恒流充电条件下，一致性保持在95%左右。
[Abstract]:With the increasing shortage of resources and environmental pollution and the continuous improvement of vehicle ownership, the research and development and promotion of new energy vehicles have become an important means for the country to formulate urban development strategy, because urban vehicles have relatively fixed daily mileage. In order to meet the continuous driving mileage of pure electric vehicles, or to achieve sufficient driving requirements and braking energy recovery efficiency, The need for on-board batteries can ensure more energy supply, which also brings the problem of heat management in battery pack. Because the temperature of battery pack is closely related to the performance and service life of battery, it also affects the reliability and safety of battery pack. It is very important to study the rules of heat generation, heat transfer and heat dissipation, to design a reasonable battery package structure and to develop an effective battery heat management system. This paper analyzes and summarizes the current research situation of battery thermal management at home and abroad, adopts the analytical method of computational fluid dynamics to select the battery type and optimize the structure, and introduces the research content of this paper. Firstly, the current research situation at home and abroad is analyzed, and the effect of battery consistency on the battery performance is studied based on the principle of lithium-ion battery reaction and heat generation. The relationship among battery capacity, internal resistance and temperature is analyzed. The target range of temperature and temperature difference control is obtained under the premise of cell consistency. Secondly, the basic principles of heat generation, heat transfer and heat dissipation of lithium ion battery are studied. Through reasonable simplification, the thermal model of lithium ion battery is obtained by using computational fluid dynamics simulation software FLUENT. The heat generation rate under constant current charging and cycle condition was obtained by fitting curve and array storage by Matlab and Advisor. The temperature field distribution of two kinds of lithium ion batteries was simulated and compared by FLUENT real-time call. It was determined that the lithium ion battery with small capacity should be connected in parallel to obtain lower temperature rise and smaller temperature difference. Finally, a battery package is modeled, and its structural parameters are changed to carry out a series of simulations. By analyzing the temperature field, pressure field and streamline distribution of the battery bag under different structural parameters, the cooling law of forced air cooling is summarized. Finally, the structural parameters of the wedge ventilation structure are determined to keep the consistency above 98% under the cyclic condition, and about 95% under the condition of fast charging and constant current charging.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM912;U469.72

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