Impedance Characterization of an Automotive Battery Pack

Parasitic inductance and capacitance of the battery pack can affect the performance of the electric powertrains. Characterizing these parasitic phenomena in an automotive battery pack is therefore crucial to ensuring performance and reliability. In this work, geometric models of a production automotive battery pack are developed to simulate the parasitic inductance of the busbar system, the parasitic inductance of individual modules, and other critical components. For these simulations, several assumptions and simplifications are introduced to reduce model complexity, while preserving the main electromagnetic behavior of the system. The impact of the different components on the battery pack impedance is investigated to evaluate parasitic capacitances, thereby simulating the worst-case scenario. Laboratory procedures are developed to accurately measure parasitic impedance, providing a reliable comparison between experimental data and analytical models and supporting the overall validity of the simulations.