Producing safe battery modules is a critical step in EV manufacturing process. Properly joining cells to busbars ensures that the connections meet electrical requirements, which are crucially important to the function, performance and reliability of the vehicle. And most importantly, the safety of the passengers.
Battery modules are made by joining together a number of battery cells (prismatic, cylindrical or pouch) and welding them together using high-conductivity busbars. For high-quality production of these components, this process can be time consuming, costly and inconsistent, all of which can contribute to less than desirable results. Adjustable Mode Beam fiber laser welding solutions and real-time weld measurement provide exceptional depth control and spatter-free welding, which are key requirements to ensure the quality of the modules and avoid defects that could prove catastrophic.
There are many overall manufacturing challenges of battery module production, but specifically when talking about busbar welding:
Challenge: The size of the weld has a direct effect on electrical resistance
Solution: Laser welding provides precision and consistency to control welds per manufacturing specifications, allowing for a uniform weld size.
Challenge: Material selections are likely to involve different metals for the busbar and cell tabs
Solution: E-mobility application experts collaborate with manufacturers to develop process parameters for welding dissimilar materials with optimum results.
Challenge: Weld placement precision and weld depth penetration is critical
Solution: For cylindrical cells, laser welding solutions integrate real-time weld measurement to control weld depth and other key welding parameters.
Laser welding has become the technology of choice for both the auto industry and e-mobility applications, thanks to several key advantages. E-mobility laser solutions provide compelling benefits to enable manufacturers to meet production requirements and deliver high-quality, safe battery modules.
The materials that are used to manufacture the battery module, whether the busbar or the battery cells, are sensitive to imperfections. Laser welding makes no contact with materials eliminating the risks associated with traditional bonding methods. This is important, because any imperfection on the materials could affect the electrical performance of the battery module and electric vehicle.
The tight process control used for laser welding is applicable both within and between tools, making the busbar welding process repeatable and faster. Processing consistency through control software and motion platforms allow for laser power stability, which eliminates weld variations, a crucial factor in busbar welding.
This is possible thanks to the high tool uptime and availability that laser welding offers, thus extending the time between required maintenance as opposed to other methods with tool wear and consumables which require frequent attention. By having a reliable source, laser welding ensures minimal downtime, increasing productivity considerably.
This is particularly important due to the multiple battery module designs that already exist, or are being created. It is easy to program the welding process to adapt to different module designs and battery cells types.
Thanks to the ease of programming and high repeatability, laser welding is considerably faster than traditional methods. For cylindrical cell batteries with thousands of connections, higher speed equates to significant production cost savings.
Whether you need to demonstrate laser processing feasibility with your parts, or just want to bounce design and implementation ideas about your e-mobility manufacturing processes off an experienced laser engineer, give us a call.
IPG is the world leader of fiber laser technology and experts in materials processing. We apply this expertise to our e-mobility solutions, with the sole purpose of offering manufacturers the necessary tools through laser processing to obtain the best e-mobility application results.
Learn more about the entire scope of E-Mobility solutions that IPG offers