基于恒流外特性和SOC的电池直流内阻测试方法

Battery DC internal resistance test method based on the constant current external characteristics and SOC

电池的直流内阻是电池内部离子电阻与电子电阻之和。它决定电池功率特性,同时也反映电池的老化状况与一致性,因此对于电池的外特性建模与应用非常重要。该文提出了一种基于电池恒流外特性的直流内阻测试方法。该方法将不同恒流工况下的电池荷电状态(state of charge,SOC)变化过程归一化,从而能够利用恒流充放电曲线来获取不同工作电流及SOC条件下的直流内阻。该方法在保证测试精度的同时比已有方法更加简便。

The direct current internal resistance（DCIR）is the sum of a battery＇s ionic and electronic resistances.The DCIR test indicates the battery＇s power characteristics and reflects the batteries＇aging and uniformity characteristics.Thus,it is important for battery modeling and applications.This paper describes a DCIR test method based on the battery＇s constant current external characteristics.This method normalizes the battery＇s state of charge（SOC）changes for different constant current conditions.Then,the DCIR for different operating currents and SOC are obtained using constant current charge/discharge curves.This method is easier to implement than existing methods and has good accuracy.