Internal heat self-generation in lifepo₄ battery module

Currently, lithium-ion batteries (LIBs) are widely used in electric vehicles and renewable energy systems, which require substantial energy storage capacities. Although the LIB has the advantages of enhanced energy efficiency and power density, thermal runaway and the ensuing degradation of the batteries are challenges that remain. The effects of self-generated heat include reduced lifespan of the LIB and thermal runaway in the module configuration owing to unreleased heat from the boundary of neighboring cells. In this study, a spatial resolution temperature monitoring system was employed to investigate the self-generated heat of a LiFePO₄-based LIB module. The investigations revealed that there is a significant increase in the surface temperature as well as in the difference between surface and internal cell temperatures, with increasing charge-discharge rates in the range of 0.2–2 C (14–140 A). Furthermore, the temperature increases of LIB modules were higher at high discharge rates above 0.7 C (49 A) and lower at relatively low discharge rates such as 0.2 C (14 A) and 0.5 C (35 A).