Abstract
Analysis of hotspots in battery system is important as it indicates the thermal stresses arising and the occurrence of thermal runways. The battery heat generation and coolant flow system are together studied in this work using finite volume method. The role of different class of coolants like nanofluids, gases, oils, and liquid metals combined with the variations in spacings between the battery cells is specifically focused. In addition, effect of battery aspect ratio, coolant velocity, and their thermal conductivity are analysed in detail. The hotspots intensity and their locations are accessed for all the factors mentioned above. Later, using modern algorithms like X-gradient boosting (XGB) and decision tree (DT) the predictions of hotspots and their locations is performed. From the numerical analysis, it is found that the hotspots get affected by changes in the chosen parameters except aspect ratio. It is found that, in an operating range of battery system with different heat generations and coolants, there is always a limiting value above/below which simply increasing/decreasing the parameter, does not reduce battery hotspots for sustainable performance. Both the algorithms used, predict the hotspot with a low accuracy of R-2 value 0.55 and 0.53 using DT and XGB algorithm. The hotspots location is predicted with high accuracy having R-2 value close to 0.92 from both the models.