The Structure Optimization of Lithium-ion Battery Pack Based on Fluid-solid Conjugate Thermodynamic Analysis

Abstract

To effectively improve the discharging efficiency and the cycle period, the thermodynamic analysis and the heat dissipation structure optimization are conducted on the lithium-iron battery pack. The internal resistance characteristics of the battery are experimented, and the change of internal resistance at different discharge rate and ambient temperature is measured. The three-dimensional thermal effect model of the battery is established, and the simulation analysis of thermoelectric coupling is carried out by using MSMD model in FLUENT. The simulation results are compared with the experimental results to verify the validity of the model. By the Ansys Workbench software, the three dimensional model are established based on the conjugate thermal transfer phenomenon. Based on the fluid-solid conjugate heat transfer mechanism, the influence of the airflow channel spacing and air inlet angle on the temperature distribution of the battery pack is analyzed, thus optimizing the heat dissipation structure. By studying the effect of the air flow rate and its temperature on the temperature distribution of the battery pack, the optimized heat dissipation structure can achieve the best performance.