Experimental study and numerical modeling on cylindrical lithium-ion power battery thermal inertia

Thermal issues are increasingly critical for the scaling-up and integrated deployment of lithium-ion batteries (LIBs). Many studies have investigated thermal management of battery packs; however, few have investigated thermal inertia of batteries, which is the basis for battery thermal management design. Experimental results show that the thermal inertia can greatly affect the thermal behavior of the battery during discharging. Thus, a battery thermal model is created using COMSOL multiphysics software, and infrared imaging is used to investigate the thermal inertia for a LiFePO (LFP) battery under natural convection. The model and corresponding simulation could provide helpful references for the design and control of the thermal behavior of batteries and to improve their performance. The temperature distribution and variation trend of the internal temperature, surface temperature, and temperature difference in the slack period after discharge were studied. The results indicate that the battery radius (R) and discharge rate (C) are the main factors influencing thermal inertia.