Thermal model analysis of large-scale Li-ion battery

摘要

A three-dimensional thermal model was been developed for a 50 Ah large-scale Li-ion battery. From a practical point of view, both with the accuracy of the calculations, the three-dimensional system was degraded to a two-dimensional system base on "Numerical Heat Transfer". The temperature distribution and change with time has been simulated during the course of 0.2C charge 0.5C discharge and cycle at 0.4C charge 0.45C discharge. Compare the simulation result with the test result, it was find the simulation result of surface temperature distribution basically consist with the test result, the temperature error within 1 centigrade. It suggested the thermal model was exact and reliable. Based on previous result, the interior temperature change and distribution was studied in a detail way, it was found that the polar temperature was 2-3 centigrade higher than that of the battery center and the temperature distribution in the interior of the battery was comparatively uniform which indicate the heat dissipation performance of the cell body produced with our technics was Very good. The thermal model could be used to optimize the structure of large-scale Li-ion battery and promote the practical use of large-scale Li-ion battery.