考虑集肤效应和高频额外产热的锂离子电池等效电化学阻抗热耦合模型

Equivalent electrochemical impedance-thermal coupling model for lithium-ion batteries considering skin effect and high-frequency additional heat

建立一种合理的等效电化学阻抗-热耦合模型对采用高频交流电(AC)进行电池低温加热过程中的阻抗计算和温度预测具有重要意义。采用NSGA-II算法对7种不同的等效阻抗模型在10~100000 Hz频率范围进行参数辨识后,通过对比发现在高频部分,与单个电感模块相比,采用一个电阻和电感并联模块能够在不增加计算量的条件下更准确地描述集肤效应对阻抗曲线的影响;在利用依靠电池自身能量进行低温加热的拓扑结构获取了不同频率下的高频额外产热和随温度时变的换热系数后,建立了一种适用于高频AC加热的电池等效电化学阻抗-热耦合模型;在恒定频率加热下验证了模型的准确性,证明了采用随温度时变的换热系数进行温度预测的必要性;在变频加热下验证了模型的实用性,且与现有模型相比,在高频范围内的温度预测最大误差从2.93℃降为0.35℃,RMSE仅为0.23℃。

Developing an accurate equivalent electrochemical impedance-thermal coupling model is crucial for calculating impedance and estimating temperature during low-temperature heating of batteries using high-frequency alternating current(AC).The NSGA-II algorithm was used to identify parameters for seven equivalent impedance models across a frequency range of 10 Hz to 100000 Hz.The study found that a model using a resistor and inductor parallel module better accounts for the skin effect at high frequencies without increasing computational complexity compared to a single inductor module.The proposed model,which incorporates time-varying heat transfer coefficients and high-frequency additional heat,was validated under both constant-frequency and variable-frequency conditions.It reduced the maximum temperature prediction error from 2.93℃ to 0.35℃,with an RMSE of only 0.23℃ compared with existing models,proving its practicality and accuracy.