A Reduction Method for Thermal Modeling of Lithium-ion Battery based on Proper Orthogonal Decomposition

Battery thermal management system (BTMS) is crucial to ensure the safety and performance of lithium ion battery. To reflect the temperature distribution of the battery, an accurate thermal model of lithium ion battery is needed for the BTMS. However, the existing thermal models of lithium ion battery cannot give consideration to both the efficiency and accuracy of calculation. In this paper, a reduced-order thermal model (ROTM) was established to estimate the temperature distribution of lithium ion batteries online. Firstly, the proper orthogonal decomposition (POD) method was used to extract eigenfunctions from the thermal field of lithium-ion battery. Secondly, the ROTM can be obtained by projecting the eigenfunctions to the thermal equation of the lithium-ion battery using Galerkin method. Finally, the accuracy and efficiency of the ROTM was verified by comparing with the finite element method (FEM). The computational results of the ROTM are in very good agreement with that of FEM, but the ROTM can save more computational time. Thus, such ROTM can be applied to the real-time processing control of BTMS.