Modular battery cell model for thermal management modelling

Internal policies of the major car markets are urging for a cut in oil imports, leading to powertrain electrification. Due to their high weight-to-power ratio, Lithium-ion batteries, especially Lithium-Nickel-Manganese-Cobalt Oxide 21700 cylindrical cells, are rapidly becoming the most diffused electric powertrain energy storage devices. These devices need to be operated in a tight temperature range to prevent major power drops and also for safety reasons. It is therefore essential to provide an accurate but computationally inexpensive battery model. Current models are either too simplistic and not applicable for thermal management design purposes or too computationally expensive and impractical for heat exchange modelling purposes. This work was focused on a computationally convenient system-level-modelling-oriented battery cell model. Starting from a 1D model obtained from manufacturer’s data, experiments were carried out on real cells, a more sophisticated 3D model for cell characterization was implemented and then a lighter 1D model obtained from it was proposed. The outcome is a novel thermal model of batteries, with a reasonable computational cost, developed on the purpose of thermal management design. This represents an advancement in battery thermal management design, as no such model is currently available in literature.