Current Distribution and Anode Potential Modeling in Battery Modules With a Real-World Busbar System

The performance of a lithium-ion (Li-ion) battery pack is not only related to the behavior of the individual cells within the pack, but also presents a strong interdependency with the temperature distributions, interconnect resistance between cells, and the cell's physical location within the complete battery pack. This article develops representative busbar circuits with different fidelities to simulate the behavior of cells within a battery module and analyses the influence of cell-to-cell heat transfer and interconnect resistance on the distribution of cell current and anode potential in a battery module. This work investigates multiphysics interactions within the battery module, including cells, interconnect resistances, and temperature distributions, while analyzing the lithium plating problem at the module level. Specifically, the cell model used in this study is a validated thermally coupled single-particle model with electrolyte (TSPMe), and the battery module uses a commercially representative busbar design to include 30-cells in parallel. The effects of parameter changes within the battery pack on individual cells are simulated and analyzed. The study highlights that some cells in the battery module would present a higher risk of lithium plating during fast-charge conditions as they experience a lower anode potential during the charge events.