锂离子电池简化电化学模型理论误差分析研究  

Investigation on Theoretical Errors of Simplified Electrochemical Models for Lithium-ion Batteries

作　　者：谢奕展 程夕明[1] XIE Yizhan;CHENG Ximing(National Engineering Research Center of Electric Vehicles,Beijing Institute of Technology,Beijing 100081)

机构地区：[1]北京理工大学电动车辆国家工程研究中心,北京100081

出　　处：《机械工程学报》2022年第22期37-55,共19页Journal of Mechanical Engineering

基　　金：国家重点研发计划(2021YFF0601101);国家自然科学基金(51677006)资助项目。

摘　　要：准确的电池模型是电池状态估计和能量管理的基础。锂离子电池电化学模型描述电池内部机理,具有物理意义明确和准确度高的优点。目前,常用的电化学模型为P2D伪二维电化学模型、SPM单粒子模型和SPMe考虑电解质动态的单粒子模型。其中,P2D模型的精度最高而计算量最大,而简化模型SPM或SPMe的计算效率高,但存在模型简化产生的误差。为探究误差的产生机理,首先比较SPM、SPMe和P2D模型的电极电流源、固相浓度和液相浓度,然后从平衡电势、过电势、液相浓差极化电势、液相欧姆压降和端电压对简化模型进行了误差分析,并指出误差传递路径。结果表明,电极电流源是模型端电压误差产生的根源,液相正负极欧姆压降和负极平衡电势误差是端电压误差的主要来源。上述结果可为SPM和SPMe模型的误差补偿方法设计提供理论依据。最后还提出了模型端电压误差补偿建议。An accurate battery model is the basis of battery state estimation and energy management. Electrochemical models of lithium-ion batteries can describe their mechanism and have the advantages of clear physical interpretation and high accuracy.Currently, the commonly used electrochemical models are the pseudo-two-dimensional electrochemical model(P2D), the single-particle model(SPM), and the single-particle model with electrolyte dynamics(SPMe). Among them, the P2D model has the highest accuracy with the largest computational burden, while the two simplified models of the SPM and SPMe can run efficiently but suffer from the errors resulting from model simplification. To explore the error mechanism, the electrode current source, the solid-phase concentration, and the liquid-phase concentration of the SPM, SPMe, and P2D models are compared, and then the model errors of the simplified models are analyzed in terms of the equilibrium potential, overpotential, liquid-phase concentration polarization potential, liquid-phase ohmic potential drop, and model voltage. In addition, the model error path is given. The results show that the electrode current source is the origin of the model output voltage error, and the liquid-phase positive ohmic potential drop, the liquid-phase negative ohmic potential drop, and the negative equilibrium potential errors are the main sources to generate the model output voltage errors. The above results can provide a theoretical basis on designing error compensation for both the SPM and SPMe models. Finally, suggestions on how to compensate for the model output voltage error are also provided.

关 键 词：锂离子电池 伪二维电化学模型 单粒子模型 误差分析 

分 类 号：TM912[电气工程—电力电子与电力传动]