Thermal Modeling of a Prismatic Lithium-Ion Battery for Urban Energy System Applications

The growing adoption of electric vehicles, alongside global efforts to develop low-carbon and sustainable cities, is driving a significant transformation in how energy should be generated and consumed in urban environments. Within this context, the thermal management of lithium-ion batteries is essential in terms of the safety and energy efficiency of electric vehicles. This study investigates the thermal behavior of a prismatic 50 Ah LiFePO4 cell using a 2RC electric model coupled with a three-dimensional thermal network model. The approach is extended to a module of five cells connected in series. Open circuit voltage, impedance parameters, and entropic coefficient are obtained experimentally, whereas thermal resistances and heat capacity are estimated using a simple, cost-effective approach under reasonable assumptions. The developed electrothermal model, together with the characterized electric and thermal parameters, was employed to predict temperature evolution under operating conditions representative of intensive EV usage. The developed models for both single cell and battery module demonstrate strong predictive capability, with temperature deviations limited to approximately 1.5 °C and 1 °C for the single cell across the scenario applied and around 3.5 °C for the module, where the cells were exposed to a significant increase of temperature throughout the scenario applied.