Structure optimization of parallel air-cooled battery thermal management system with U-type flow for cooling efficiency improvement

In this paper, the cooling efficiency of the parallel air-cooled battery thermal management system (BTMS) with U-type flow is improved through optimizing the structure of the system. The flow resistance network model is developed to calculate the airflow rates of the cooling channels in the system. Based on the developed flow resistance network model, the angles of the plenums and the widths of the inlet and the outlet are optimized using the nested looped procedure and the numeration method. The numerical results of typical cases show that the temperature and the temperature difference among the battery cells cannot be effective reduced through arranging the angles of the plenums of the system, while optimizing the widths of the inlet and the outlet can remarkably improve the cooling efficiency of the BTMS. For the process with 5C discharge rate process, the temperature difference among the battery cells is reduced by 70% after optimization, with the power consumption reduced by 32%. Moreover, compared to the optimized BTMS in the previous study, the temperature difference among the battery cell for the present optimized BTMS is 43% lower, with power consumption reduced by 50%. The similar improvement can be achieved for various inlet airflow rates.