Canada-based Laserax, which manufactures industrial laser machines, has developed a new system that accelerates the laser welding of battery cells using machine vision software from German firm MVTec.

The Battery Welding Machine speeds up the process of welding the current collector and busbar to the battery module. The system is suitable for batteries used in the automotive industry, for automated guided vehicles (AGVs), e-bikes, and for power tools.

During the process, a battery module is fed into the machine through an opening on the side. Inside the housing, four SCARA robots sequentially clamp and connect the battery module contacts using a laser welding process. This enables the production of battery modules at a faster pace while reducing waste compared to ultrasonic bonding or various welding methods such as spot or resistance welding, according to the company.

The machine uses MVTec’s HALCON machine vision software to localize the battery module cells, so that the robots can carry out the clamping and laser welding work with precision.

Two cameras are attached to the side of the laser scan head to allow 3D stereoscopic vision. They take high-resolution images of the battery module on a 400 x 400 mm area from above. The HALCON software then calculates the positions of all the cells by merging the images from the two cameras.

The coordinates are transmitted to the clamping robots and the laser system. The precise position of each spot to be welded on the cells is determined with an accuracy that allows the robots to weld each cell in less than 100 ms. Weld quality monitoring is performed in real time using a dedicated sensor that captures the light emitted.

“We realized that our customers from the battery industry are specifically looking for a solution to weld the current collector and the busbar to the battery module. Although there were already other methods for connecting, these could not offer the necessary speed and quality. That’s why we developed our own system for this process, based on laser welding,” said Keven Tremblay, Product Line Manager at Laserax.

Source: MVTec