A lumped electro-thermal model for a battery module with a novel hybrid cooling system

Abstract

An accurate thermal model is one of the keys to a thermal management system. However modeling of these battery modules based on lumped thermal model is challenging. The extension of the single battery model to a multi-battery model requires not only the connection between the electrical models of the multiple batteries, but also the consideration of the heat transfer between the batteries and the BTMS. In this paper, a lumped electrical-thermal model is proposed for the investigation of a complex hybrid cooling systems. The proposed model enables the cell to cell temperature variations analysis with the hybrid cooling thermal management system under the 1D level, which has considerable time savings compared to running a 3D numerical model simulation. A good agreement between experimental and simulation results is observed. The maximum error for the voltage calculation is 1.64%. The maximum differences between the modelled and experimental results for battery module temperatures are 4.5% and 1.7%, corresponding to the battery in the middle and at the ends of the module, respectively. To compare with the 3D numerical model, similar CFD simulations have been performed. Although this model has an approximate accuracy loss of around 1%, the model only requires 3.9% of the time required by the CFD model. The proposed model is computationally efficient and can be easily used to optimise algorithms to optimise temperature control during battery module operation.