Optimal Battery Cell Design for Electric Vehicles-A Holistic Method with Consideration of Ageing due to Electrothermal Gradients

Battery design is essential for the competitiveness of a battery electric vehicle (BEV) in terms of performance and costs. The objective of the authors research work is to develop a method to determine the optimal cell size for BEVs. A review of the state of the art reveals the need for further investigations on the effect of the cell size on aging due to higher electrothermal gradients in the increasing cell sizes used in the automotive industry. Hence, the research question How do electrothermal gradients influence the ageing of lithium-ion cells of different sizes for battery electric vehicles? is derived. The developed electrothermal ageing model is to be integrated in a state-of-the-art holistic method to determine the cell size considering electrothermal performance, aging, safety and costs. The suited electrothermal aging model is developed through the comparison of modelling approaches with different combinations of electrochemical and empirical models. Furthermore, the concept for the experimental aging series for the parametrization and validation of the model is presented. Results will follow beginning of 2020. The raw data will be published.