电动汽车用锂离子电池荷电状态定义和估算方法

摘要

The main problems of existing SOC (state of charge) definition methods were analyzed, the concept of maximum available capacity was proposed based on the open circuit voltage (OC V) of a battery, and the battery SOC was redefined, thus the decoupling of a battery' s charge/discharge capacity and work condition was realized. Through updating the maximum available capacity of a battery, the effect of aging on the SOC estimation accuracy was avoided. By converting the internal resistance voltage drop and the polarization voltage into the loss of discharge capacity, a method for calculating the actual available capacity of a battery or a battery pack was achieved, and its validity and feasibility were verified.%分析了现有电池荷电状态(SOC)定义方法的主要问题,基于电池的开路电压提出最大可用容量的概念,并对电池的SOC重新进行定义,从而实现了充放电容量与电池工况之间的解耦；通过更新电池的最大可用容量,避免了老化对SOC估算精度的影响；通过将电池的欧姆压降和极化电压折合到放电容量的损失上,得到电池和电池组实际可用容量的计算方法,并验证了其有效性和可行性.