基于充电曲线特征的退役动力电池容量估计方法研究

Research on capacity estimation method of decommissioned power battery based on characteristic of charging curve

退役动力电池的容量是划分电池梯次应用场景的关键参数。电池荷电状态(SOC)和健康状态(SOH)估计是设计安全、高效电池管理系统的重要依据。容量参数测量时间尺度长,易受运行工况、工作环境等因素的影响,其估计问题一直是阻碍退役电池大规模梯次利用的难题之一。以三元锂电池为研究对象,提出一种基于充电曲线电压特征点的退役动力电池容量快速估计方法,将基于1 C下的恒流充电(CC)阶段电压-时间曲线分为两个电压区间,从中提取容量估计特征参数;随后,采用支持向量回归方法构造容量估计模型,并对照实测数据,验证该方法的有效性与准确性。

The capacity of decommissioned power batteries is a critical parameter for classifying the battery application scenarios.The battery state of charge(SOC)and state of health(SOH)estimation are important foundations for designing the safe and efficient battery management systems.The measurement of capacity parameters is time-consuming and susceptible to the factors such as operating conditions and working environments.The estimation of capacity has always been one of the challenges hindering the large-scale utilization of decommissioned batteries.Taking the ternary lithium batteries as the research object,a rapid capacity estimation method for decommissioned power batteries was proposed based on the voltage characteristic points in the charging curve.The voltage-time curve during CC charging stage at 1 C was divided into two voltage intervals,from which the capacity estimation characteristic parameters were extracted.A support vector regression method was employed to construct a capacity estimation model,and the effectiveness and accuracy of the method were validated against the actual measurement data.