Lithium-ion batteries will become a key element in future electro mobility. In a layered pouch cell design the electrical contacts consist of conductive foil tapes that have to be welded to the terminal. Common used ultra-sonic welding technologies have some process inherent restrictions like risk for mechanical damaging of the 10…20 µm thin Al or Cu foils, wear of the welding-sonotrode and limited mechanical strength and electrical conductivity of the welding spot caused by the adhesive bonding interfaces.
For a high volume and high power applications for future electro mobility the laser beam welding technology with high quality (HQ) solid state laser offers new possibilities. Beside the easy laser beam welding (LBW) process automation a higher strength and a lower electrical resistance of the weld caused by a fully metallic bonding can be achieved. But laser beam welding of 10…20 µm thin foil packages is challenging with respect to the gap condition in overlap configuration, necessary new clamping concepts and welding strategies to minimize the heat input. In the paper weld joint geometries, influence of laser sources and beam deflection techniques will be specifically analyzed.