By Keven Tremblay on May 15, 2024
Laser Welding
With the rapid growth of EVs in the automotive industry, battery welding has become an important challenge to keep up with demanding production requirements. At Laserax, we have developed a laser welding cell that addresses these challenges.
This fully automated solution combines laser welding with SCARA robots, dynamic clamping tools, vision analysis, and in-process monitoring.
Combining these features, this welding cell is designed to produce one battery module every minute while maintaining strict quality requirements of 99.999% good welds.
In this article, we’ll look at the important features that make up this solution.
Table of Content
- Remote Laser Welding Head
- 3D Vision System
- Dynamic Clamping with SCARA Robots
- Fume Extraction & Clamping Tool Cleaning
- Laser Source
- Laser Safety Enclosure
- In-Process Monitoring
- Laser Welding Cell for Battery Video Presentation
Remote Laser Welding Head
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With our remote laser head, laser welding can be performed at ≈600 mm from the battery module. The laser beam is guided by an optical fiber that produces a small high-intensity spot size, resulting in high precision and a good penetration depth. The laser head has a field of view of 400 x 400 mm, allowing to process battery modules one section at a time. Mounted on a gantry system, it can also be moved above different sections of the module to weld all the battery cells in a single operation. |
Remote laser head mounted on a gantry system. |
3D Vision System
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Prior to welding, a 3D vision system is used to capture the XYZ position of each individual cell in the laser’s field of view. It can analyse the position of up to 150 cells in a single snapshot. The vision cameras are complemented by lighting equipment to make sure the depth of the cells is perceived properly. |
Cameras move with the laser head on the gantry system. |
Dynamic Clamping with SCARA Robots
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Clamping tools are mounted on SCARA robots that apply the right amount of pressure on each cell connection to be welded. With vision analysis, the clamping tool position is adapted to each cell. By using several robots, clamping generates no waiting time for the laser. This ensures that the laser is always welding, reaching a cycle time of around 100 milliseconds per cell. |
Clamping tool mounted on a SCARA robot (top). Pressure applied on the cell-to-busbar connection (bottom). |
Fume Extraction & Clamping Tool Cleaning
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To achieve quality welds on every module, it’s essential to keep the work environment clean. Contaminants can cause short circuits, affect optics, and create thermal lensing. The extraction system needs to be as close as possible to the weld. To do this, the extraction nozzle is mounted directly on the clamping tool. In between modules, SCARA robots move the clamping tools to automated cleaning stations where the clamping tip is cleaned with compressed air. |
Clamping tool being cleaned with compressed air, with an extraction nozzle under. |
Laser Source
- The fiber laser system has a wavelength of 1070 nm, making it ideal to weld metals like aluminum, steel, and copper.
- It comes with up to 6kW of laser power to meet the most demanding cycle time requirements.
- The continuous-wave laser beam output provides continuous beam delivery with sustained heat transfer, making it easy to accommodate welds of different sizes. It can be used to weld busbars with a thickness varying between 100 μm and more than 1.5 mm.
- Single mode laser technology generates a small spot size that offers excellent control over the heat input. This results in high-quality welds with a low heat-affected zone (HAZ).
Laser Safety Enclosure
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Our laser welding cell is a certified class-1 laser product and comes with the legal documentation ready to be submitted to organizations like the FDA. The enclosure contains the beam and its reflections, protecting your workers and your work environment from the powerful laser used for welding. |
Class-1 laser safety enclosure of the laser welding cell. |
In-Process Monitoring
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The accuracy of the laser welding process is validated in real time with an LWM system. This system automatically detects bad welds by analyzing signals emitted during welding. Monitoring is used to automatically send bad welds for rework. It is trained using data from good welds based on your specifications. You can find more information on how LWM systems work here. |
Weld monitoring data is available for the positive and negative poles of every cell in the HMI. |
Laser Welding Cell for Battery Video Presentation
Discover Your Options for an Automated Welding Cell
If you want to explore welding solutions for battery pack and module production, our experts can guide you. They can assist in the design phase of your product as well as for the integration in a full-scale production line.
We also offer a variety of services, including the rental of a workstation for product development and small-scale production, the development of a custom laser welding process, and the welding of complete modules.
