恒流充放电过程中双电层电容器温度特性

Temperature characteristic of electric double layer capacitor under galvanostatic cycling

温度特性是双电层电容器的重要特性之一,在电容器充放电过程中伴随着可逆热和不可逆热的产生。利用有限元技术对双电层电容器在恒流充放电循环过程中的内部及外部传热进行数值模拟。同时,对一个双电层电容器样品在循环过程中的内部及外部温度变化进行了测量。对数值模拟结果和实验数据进行对比,分析了恒流充放电循环过程中双电层电容器内部和外部的传热特性、温度分布及其发展变化,讨论了循环过程中电容器可逆热的变化规律及其影响因素,以及由可逆热引起的温度波动的变化。另外,实验数据表明,超级电容器在大电流充放电过程中需要进行冷却。

Temperature characteristic is one of the important properties for an electric double layer capacitor（EDLC）, and the reversible and irreversible heat are combined with the charging and discharging for an EDLC. In this study, the numerical simulation of heat transfer, conducted with the finite element technology, and temperature measurement inside and outside EDLC were performed during galvanostatic cycling with different current densities. The heat transfer characteristics and temperature distribution were analyzed by the comparison between the simulated and measured temperatures. And then, the variation and the influencing factors of reversible heat and temperature oscillation during galvanostatic cycling were discussed. Meanwhile, the EDLCs need to be cooled during charging and discharging cycles with great current according to the measured results.