To reduce fuel and maintenance costs as well as carbon emissions, companies are investing in electric trucks for their delivery fleets. While turning to electric trucks is a promising solution, the battery packs incorporated into these automotive designs often fall short in the lifetime needed to make long-distance highway travel feasible.
To help overcome the issue of battery lifetime, a consortium of universities and industry partners incorporated multiscale simulation and a custom simulation app into the battery manufacturing process. The organizations involved in this project were Aurobay, Resolvent, the European Commission, the Technical University of Denmark (DTU), Vinnova (the Swedish Agency for Innovation Systems), Innovation Fund Denmark and Volvo Group Trucks Operations.
The simulation app, built by Resolvent, a Denmark-based engineering consultancy that specializes in green energy, enables the R&D department at Volvo to easily test battery lifetime performance.
Figure 1. A Volvo® electric truck.
LaserWho?
The Multiscale Simulation of Laser Welding for Optimal Battery Pack Manufacturing project — referred to as "LaserBATMAN" — was initiated in May 2022 and wrapped up in May 2025. Although BATMAN here refers to battery manufacturing and not the famous masked superhero, the goals for the project also strove for greatness.
The LaserBATMAN project aimed to optimize two key performance metrics for battery packs: robustness and lifetime. One element of the battery manufacturing process that affects both of these metrics is the laser welding used in component joining processes. If done correctly, laser welding can positively impact battery life, but if done incorrectly, laser welding can increase the risk of battery degradation. Computational modeling can be used to analyze and predict the effects of welding and joining processes at different stages of the manufacturing process.
Martin Refslund Nielsen, former chief commercial officer and partner at Resolvent, explained that for this type of multiphysics and multiscale problem, “COMSOL Multiphysics is just the right tool.”
R&D workflow for multiscale model and app
The Resolvent team used the COMSOL Multiphysics® software to study how laser welding affects the electrochemistry and degradation of battery cells. At least, that is how the project started.
“Ambitions grew,” Nielsen said, explaining that the team ultimately modeled the performance of the entire battery, from the cell to the pack level. They even “turned [the model] into a design tool in the end,” he added, referring to the app (Figure 2).
First, the team built an electrochemical model of a battery cell. The resulting electrochemical model of the cell was fed input data and the output data was used to train a deep neural network (DNN). With this surrogate model, the team was able to quickly gain insight into cell behavior.
After training the DNN of the battery model, the team built a custom simulation app to optimize busbar tabs in the configuration of a battery pack.
Figure 2. The Resolvent battery model.
The features of the simulation app include options to input dimensions for the pack geometry, the number of cells and operating conditions such as ambient temperature and charge–discharge current profiles. Users are able to see how the battery performs with each set of inputs.
Another important aspect of the app is the Busbar Weld Design Tool button, which can be used to efficiently calculate busbar weld performance after a number of cycles.
Predicting pack performance
The app also includes a Compute Battery button, which can be used to see the temperature of the weld in a given state, the state of charge and the solid–electrolyte interface (SEI) layer thickness (Figure 3). The results can help the team determine if there is room for optimization in the design. For instance, a user can apply a cooling flow in the app and see if turbulence occurs.
As explained by Nielsen, apps offer more consistent analysis and reporting and the intuitiveness of custom apps makes it easier to share knowledge. “We are in a much better place to optimize performance and increase robustness," said Nielsen.
Figure 3. Temperature in the given state (left), state of charge (middle) and SEI layer thickness (right) in the battery pack.
The custom simulation app developed by the LaserBATMAN consortium can be used to help produce more robust battery designs with ranges that can support highway travel over longer distances with fewer failures — all while promoting the use of green energy. A heroic project indeed.
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