Investigation of thermal behavior of lithium-ion batteries with multi-scale multidimensional battery model

In this study, the effects of discharge parameters on maximum battery temperature and temperature distribution of a rechargeable ICR 26650 LiCoO2 battery were investigated. C-rate, heat transfer coefficient and ambient temperature were selected as discharge parameters. For C-rate, 1 C, 2 C, 3 C and 4 C levels, for heat transfer coefficient 5 Wm-2 K-1, 10 Wm-2 K-1, 15 Wm-2 K-1 and 20 Wm-2 K-1 levels and finally for ambient temperature 298 K, 303 K, 308 K and 313 K levels were determined. The determined factors and levels were optimized by Taguchi design of experiments method. ANSYS Fluent simulation studies were performed according to the L16 (43) orthogonal array. C-rate is the most effective factor on maximum battery temperature. It is determined that C-rate and ambient temperature have a statistically greater effect on the maximum battery temperature than the heat transfer coefficient. At 1% C-rate, 10 Wm-2 K-1 and 298 K levels, the maximum battery temperature was found to be minimum. It was determined that there is a statistically significant relationship between the C-rate and ambient temperature factors and the Tmax response variable according to the 95% confidence interval. Heat transfer coefficient is the most effective factor on temperature distribution. C-rate and heat transfer coefficient are more effective factors on temperature distribution than ambient temperature. At 1 C-rate, 20 Wm-2 K-1 and 318 K levels, the temperature distribution was found to be minimum. It was determined that there is a statistically significant relationship between the heat transfer coefficient, C-rate and ambient temperature factors and the response variables for ΔTmax according to the 95% confidence interval. The results obtained from this study can be used in the thermal management of lithium-ion batteries.