锂离子电容器的热特性及热模型

Thermal characteristics and model of lithium-ion capacitor

锂离子电容器具有寿命长、兼顾功率密度和能量密度等优点,充分了解其热特性对其广泛应用意义重大。在多种充放电倍率下进行了锂离子电容器的温升测试,并基于MATLAB和COMSOL Multiphysics 5.4软件进行了其热模型建立及研究。结果表明,随着充放电倍率的增大,锂离子电容器的发热量增加;基于MATLAB建立的集总参数热模型可以实现平均绝对误差不超过0.2℃的温升模拟;基于COMSOL构建的热模型中,随着放电倍率增加,温度分布差异增大,而将极耳布置方式改为对角布置可减小温度分布差异,使温度分布更加均匀,更有利于其性能发挥。

A lithium-ion capacitor(LIC)has the advantages of long cycle life,high power density,and high energy density.Comprehensive knowledge of LIC thermal characteristics is essential for its practical application.In this study,a temperature rise test of an LIC is performed under various charge and discharge rates,and its thermal model is established and studied based on MATLAB and COMSOL Multiphysics 5.4 software.The results demonstrate that the calorific value of LIC increases with the rise in charge and discharge rates.Based on the lumped parameter thermal model established in MATLAB,the mean absolute error in the temperature rise simulation can be limited to 0.2℃,and the temperature distribution variation increases with the rise in discharge rate.By installing the LIC lugs diagonally on the cell,the temperature difference is reduced,making the temperature more uniform,and the arrangement is advantageous in improving performance.