锂离子电池统一充电模型研究

Modeling of unified charging of lithium-ion batteries

由于电池工作特性的非线性特征,要想获得不同电流充满电的充电时间,需要建立电池的统一充电模型。对锂离子电池进行了0.2 C和1 C的充电实验,将不同电流的充电时间进行标准化,去除欧姆内阻影响后,两条充电电压-时间曲线表现了很高的相似度;采用最小二乘法对锂离子电池充电曲线进行拟合,获得恒温条件下,不同倍率的充电曲线模型。用该模型分别对0.4 C、0.5 C、0.6 C、0.8 C、1 C和1.2 C的充电曲线进行预测,充电至截止电压的时间与试验实际值的误差分别为0.4、0.63、0.8、1.24、1.22、1.13 min。实验表明,充电模型可用来预测不同充电电流的充电时间,为充电控制策略的制定提供了数据支持。

Since the nonlinear characteristics of lithium-ion battery operation, it is necessary to establish a unified battery charge model to obtain the full charging time for different charge currents. In this paper, lithium-ion batteries were charged at 0.2C and 1C, the charging times were standardized and the effects of ohmic resistance were removed. The results show that both charging curves are similar. The lithium-ion battery charging curves were fitted through the least square method, and a charging model was built under constant temperature at different charging rates with constant current. The model was used to predict the time errors and the time error between the predicted time to charge cutoff voltage and the actual time is 0.4, 0.63, 0.8, 1.24, 1.22 and 1.13 min when charged at 0.4C,0.5C, 0.6C, 0.8C, 1C and 1.2C. The experiments show that charging models can be used to predict the charging time and provide data support for the charging control strategy.