储能科学与技术 ›› 2020, Vol. 9 ›› Issue (1): 124-130.doi: 10.19799/j.cnki.2095-4239.2019.0185

• 储能系统与工程 • 上一篇    下一篇

基于多尺度锂离子电池电化学及热行为仿真实验研究

张志超1,2,3, 郑莉莉1,2,3, 杜光超1,2,3, 戴作强1,2,3(), 张洪生4   

  1. 1. 青岛大学机电工程学院
    2. 青岛大学动力集成及储能系统工程技术中心
    3. 电动汽车智能化动力集成技术国家地方联合工程技术中心(青岛),山东 青岛 260071;431620部队,安徽 六安 237000
    4. 31620部队,安徽六安237000
  • 收稿日期:2019-08-20 修回日期:2019-09-08 出版日期:2020-01-05 发布日期:2020-01-10
  • 作者简介:张志超(1995—),男,从事锂电池热失控研究,E-mail:|1378389368@qq.com;联系人:戴作强,教授,研究方向为新能源汽车系统 E-mail:daizuoqiangqdu@163.com

Electrochemical and thermal behavior simulation experiments based on multiscale lithium ion batteries

Zhichao ZHANG1,2,3, Lili ZHENG1,2,3, Guangchao DU1,2,3, Zuoqiang DAI1,2,3(), Hongsheng ZHANG4   

  1. 1. College of Mechanical and Electrical Engineering, Qingdao University
    2. School of Electromechanic Engineering, Power & Energy Storage System Research Center, Qingdao University
    3. Electric Vehicle Intelligent Power Integration Technology National and Local Joint Engineering Technology Center (Qingdao), Qingdao 260071, Shandong, China
    4. Troops of 31620, Liu'an 237000, Anhui, China
  • Received:2019-08-20 Revised:2019-09-08 Online:2020-01-05 Published:2020-01-10

摘要:

层叠式锂离子电池由许多相同的电极对单元叠加组成,每个电极对内部的物理化学特性对电池性能有着重要影响,然而,这些性质很难通过实验来测量。本文通过耦合质量、电荷、能量和电化学动力学方程,提出了一种三维电化学-热耦合模型,利用该模型,研究了层叠式锂离子电池内部电化学行为及热特性的时空分布。仿真结果表明,在放电过程中,极耳与极板连接区域电位分布与电流密度分布都存在明显的分布梯度,且在正极极耳处电流密度值最大,温升最高,放电结束时温升达到最大值8℃。电池不同位置的温升速率不同,放电前期,靠近极耳区域的温升速率较大,远离极耳处温升速率较小;随着放电过程的深入,远离极耳处的温升速率有增大趋势。本文建立的模型能够准确预测锂离子电池内部的电化学行为及温度场分布,为后续对电池的结构优化及热管理提供相关依据。

关键词: 锂离子电池, 三维电化学-热耦合, 电化学行为, 热特性

Abstract:

The stacked lithium-ion batteries comprise many identical electrode-cell combinations. The internal physicochemical properties of each electrode significantly affect the battery performance. However, these properties are difficult to be experimentally measured. In this study, a three-dimensional electrochemical-thermal coupling model is proposed by coupling the mass, charge, energy, and electrochemical kinetic equations. The time-space distribution of the electrochemical behavior and thermal properties of a stacked lithium-ion battery is studied. The simulation results denote that during the discharge process, a significant distribution gradient can be observed between the potential distribution and the current density distribution with respect to the connection between the pole and plate; furthermore, the current density is the highest at the positive pole, the increase in temperature is the highest, and the increase in temperature is reached at the end of discharge. The maximum temperature is 8 °C. The rate of increase in temperature differs at different positions of the battery. In the early discharge stage, the rate of increase in temperature is higher near the ear area and lower away from the ear; as the discharge process is deeper, the rate of increase in temperature increases away from the ear. The model established in this study can accurately predict the electrochemical behavior and temperature field distribution inside a lithium-ion battery, which will help to provide a relevant basis for subsequent structural optimization and thermal management of the batteries.

Key words: lithium-ion battery, three-dimensional electrochemical-thermal coupling, electrochemical behavior, thermal characteristics

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