(1. 北京科技大学 新材料技术研究院，北京 100083；2. 山西长征动力科技有限公司， 山西 048400；
3. 北京智行鸿远汽车有限公司，北京 102202)
摘 要: 从仿真建模的角度出发，对一款40 A？h软包叠片式动力电池建立电化学-热耦合模型，并对该构型电池的极耳结构进行了相关研究及优化工作。仿真结果显示，极耳与电芯间由于产热率的差异而引起的热流交换是电芯域内出现温度梯度分布的主要因素。在对极耳尺寸的优化中发现，电芯的最高温度随极耳宽度和厚度的增大而逐渐减小；电芯的最大温差随极耳宽度和厚度的增大在一定范围内逐渐减小，而当两者超过一定阈值(极耳宽度大于70 mm，极耳厚度大于0.5 mm)后，电芯的最大温差反而呈现出增大的趋势。原因在于极耳产热率的降低以及散热率的增加，使得在放电中后期极耳温度低于电芯温度，起到给电芯持续散热的效果，但这种散热作用随极耳尺寸的增大反而恶化了电芯温度分布的均匀性。
关键字: 电化学-热耦合模型；热参数；极耳尺寸；温度梯度
（1. School of Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China;
2. Shanxi Changzheng Power Technology Co., Ltd., Shanxi 048400, China;
3. Beijing Idrive Automotive Co., Ltd., Beijing 102202, China）
Abstract:A forward design method based on the electrochemical-thermal model was adopted for a 40 A？h laminated lithium-ion cell. Then, the tab structure of this cell was studied and optimized based on the validated model. It is found from the numerical results that the heat flux between the tab and the cell core caused by heat generation rate difference is the main factor that resulting in the temperature gradient distribution of the cell core. Optimization results of tab size show that the maximum temperature of the cell core gradually decreases with the increase in tab width and thickness. Besides, the maximum temperature difference in the cell core decreases with the increase of tab width and thickness in a certain range. But when the two parameters both exceed the threshold values (the tab width is more than 70 mm, and the tab thickness is greater than 0.5 mm), the index tends to increase. The main reason is that the decrease of the heat generation rate and the increase of the heat radiation rate of the tabs makes its temperature lower than that of the cell core, further playing a cooling effect on the cell core. However, the heat dissipation plays a bad effect on the uniformity of the cell temperature distribution to the increase in the tab size.
Key words: electrochemical-thermal model; thermal parameter; tab size; temperature gradient
