基于阻抗-电流模型的锂离子电池峰值功率估计

Peak Power Estimation of Lithium-ion Batteries Based on Impedance-Current Model

基于阻抗特性对电池的峰值功率进行预测,通过测量不同充放电电流下的电池阻抗特性,建立阻抗与电流模型。使用该模型估算电池当前状态下最大充放电电流,进而求得峰值功率。利用Arrhenius定理,考虑温度对电池阻抗的影响,基于电池在不同SOC、不同温度下的测试结果,利用Matlab拟合得出峰值功率与SOC、温度的关系。实验结果表明:通过新方法估算的峰值功率与多段脉冲实验法估算的峰值功率结果吻合。使用新模型得出的峰值功率有更高的精度,与真实值比较,相对误差为2%左右,验证了通过阻抗-电流模型获得电池峰值功率的可行性。

A new peak power estimation method with high accuracy and efficiency is presented in this paper:peak power prediction of battery based on impedance characteristics.The impedance-current model is established by measuring the impedance characteristics of different charge and discharge currents.The model is used to estimate the maximum charge and discharge current in the current state of the battery,and then the peak power can be obtained.The effect of temperature on battery impedance is considered by Arrhenius theorem.Based on the test results of battery at different SOC and temperature,the relationship between peak power and SOC and temperature is obtained by MATLAB fitting.The experimental results show that the peak power estimated by the new method is consistent with the results of multi-pulse experiment.The peak power obtained by the new model has higher precision,and the relative error compared with the real value is about 2%,which verifies the feasibility of the new method.