软包锂离子电容器放电过程热模拟

Thermal simulation for lithium-ion capacitor during discharge process

作为一种新型的电化学储能装置,锂离子电容器的热性能尚未得到重视,因此研究锂离子电容器在放电过程的温度场分布具有重要意义。通过建立三维有限元模型,利用workbench有限元软件对不同环境温度与不同放电倍率下软包锂离子电容器放电过程的温度场进行模拟研究。结果表明,在放电过程中温度逐渐升高且最高温度出现在电芯的中心区域,放电倍率越高温升越大;锂离子电容器单体的内部温差受外部环境温度影响较小。通过与实验结果进行对比验证,表明此生热模型能较好地反映锂离子电容器在实际放电过程中的温升情况,有助于其性能优化和结构设计。

The thermal behaviors of lithium-ion capacitor,as a new kind of electrochemical energy devices,have not yet attracted sufficient attentions so far.Therefore,it is significant to study the temperature distribution of lithium-ion capacitor under various conditions.In this paper,the threedimensional finite element model was established and a finite element software Workbench was employed to simulate temperature distribution at different ambient temperatures and discharge rates.The results show that the temperature of capacitor increases gradually with the discharge process going on and the highest temperature appears in the center of cell.Meanwhile,the internal temperature difference are less affected by ambient temperature.More importantly,the comparison between the simulation and experimental results shows that the heat generation model can reflect the temperature variation of the lithium ion capacitor very well during the discharge process,which is helpful to the performance optimization and structure design of lithium ion capacitors.