影响锂离子电池SOC因素的灰色关联分析

Grey incidence analysis for affecting factors of lithium-ion battery SOC

为定量分析电流、开路电压、环境温度等因素对电池荷电状态(SOC)变化率的影响,提出采用灰色理论中的灰色关联分析方法确定各个因素与SOC的灰色关联度(r)。通过建立灰色关联分析模型分析锂离子电池在不同工况下放电实验数据,确定上述因素对SOC灰色关联度,实验结果表明:放电电流对电池SOC影响最为显著(r=0.869 0),其次为开路电压(r=0.600 5),环境温度影响最小(r=0.583 1)。试验结果验证了灰色关联分析模型可定量给出每种因素的影响程度,该研究可为优化SOC预测模型和进一步提高电池SOC估算精度提供理论依据。

The state of charge（ SOC） is affected by the current,open-circuit voltage,ambient temperature and other factors. The grey relation analysis of grey theory is proposed to determine the degrees of grey relation（ r） of each factor with SOC. The grey relation analysis model is built for analyzing the discharge experimental data of lithium-ion battery which were under different working conditions. The results of experimental data show that the degrees of grey relation of these factors on the SOC changing are as follows： discharge current has the most significant influence on the SOC（ r= 0. 869 0）,the impact of open-circuit voltage（ r = 0. 600 5） is the second and the impact of ambient temperature（ r = 0. 583 1） is the minimal. These results verify the grey relation analysis model can calculate and quantify the impact of each factor which is related to SOC. This research can provide a basis for establishing the model of SOC estimation and improve the estimation accuracy of battery SOC in the future.