LiFePO4动力电池直流等效内阻温度特性研究

摘要

设计严格的实验步骤,精确控制LiFePO4电池样本的荷电状态,对其在各种特定温度下的直流等效内阻进行测定,得到电池直流等效内阻的温度特性.基于所得到的测试数据,通过参数拟合的方法,得到了在相同SOC状态下内阻关于温度的函数关系,认为二阶指数函数更接近于LiFePO4电池直流等效内阻的温度特性.所得特性规律可用于电池管理系统,便于峰值功率估算和提高热管理精度.%The testing procedures were carefully configured and SOC of the tested LiFePO4 samples were precisely controlled.The equivalent DC impedance of the battery was tested to obtain the temperature characteristics.With the test data,different functions were tried to fit the impedance-temperature curves and the 2nd-order exponential function was found with the least errors.The temperature characteristics of equivalent DC impedance can be used in battery management system (BMS) to estimate peak power and improve the accuracy of thermal management.