Electric trucks promise lower fuel costs, maintenance requirements, and carbon emissions, but battery lifetime remains a challenge for long-distance highway operation. A European research consortium involving Volvo Group Trucks Operations has developed a simulation-based approach to improve the durability and performance of electric truck battery packs, tells IEEE Spectrum.
The Multiscale Simulation of Laser Welding for Optimal Battery Pack Manufacturing project, known as LaserBATMAN, focused on improving battery robustness and lifetime. Laser welding is particularly important because it connects battery cells through components such as busbars. Poorly designed welds can contribute to degradation, while optimized welds can extend battery life.
Engineering consultancy Resolvent used COMSOL Multiphysics to model the relationship between laser welding, battery electrochemistry, and degradation. The project eventually expanded from modeling individual cells to predicting performance across the complete battery pack.
Researchers first created an electrochemical cell model based on relevant reaction kinetics. Simulation results were then used to train a deep neural network, producing a reduced-order model capable of predicting cell behavior more quickly. Resolvent incorporated this model into a custom simulation app that Volvo engineers can use as a battery design tool.
Engineers can modify battery-pack geometry, cell count, ambient temperature, and charge-discharge profiles. A dedicated Busbar Weld Design Tool allows them to vary weld shape, busbar thickness, and laser penetration depth to assess how manufacturing variations affect performance.
The app can also predict weld temperature, state of charge, and solid-electrolyte interface layer thickness. Engineers can introduce cooling airflow to identify turbulence or stagnant air and evaluate design trade-offs. Improved cooling, for example, could potentially allow designers to remove battery cells while maintaining required performance.
By packaging complex multiphysics simulation into an accessible application, the project gives engineers a more consistent way to evaluate design alternatives. The approach could ultimately support more durable electric truck batteries, longer highway ranges, and fewer battery-related failures.
