磷酸铁锂电池荷电状态估算方法研究

Research on SOC estimation method of LiFePO_4 battery

电池的荷电状态(SOC)是电池管理系统要实现的重要功能之一。精确估算电池的荷电状态能为提高电池利用率和延长电池寿命起到重要作用。分析温度、放电倍率、充放电循环次数等因素对电池容量的影响,结合磷酸铁锂电池本身的特性,提出一种改进的安时计量法与开路电压法相结合的估算方法对SOC进行在线估算。应用到自平衡两轮车上,实验测试结果显示此方法能够实时、准确地估算电池SOC。

The SOC estimation of LiFePO4 battery is one of the important functions in battery management system. The accurate SOC estimation of the battery plays an important role in improving energy utilization and extending battery life. The influence of factors such as temperature, discharge rate, charge and discharge cycles on battery capacity was analyzed. Combined with the characteristics of LiFePO4, an online SOC estimation method combining open-circuit voltage and improved current integral method was proposed. The experimental results show that when applied in the balanceable dual-wheel scooter, the method can real-time accurately estimate the SOC.