A typical lithium-ion battery (LIB) uses copper foil as the anode (current collector) and aluminum as the cathode (current collector). The welding of typically 20 to 60 foils to each other requires a high level of joining technology with long time process reliability. Burrs or cracks have to be avoided completely.
As more and more products contain rechargeable lithium-ion batteries (LIB), the battery manufacturers are aiming for ultrasonic welding as reliable battery assembly method. The specifications of the process demand a strong electric contact and no particles on the sealing film of the tab.
Ultrasonic welding offers an alternative to heat sealing the flexible LIB soft cases. The risk of damaging the cells is minimized by shorter cycle times and the use of cold ultrasonic welding tools as an alternative to hot sealing bars.
Rapid development of new energy storage systems increases the necessity for robust framework in modern battery systems. State-of-the-art busbars transfer up to 800 V and require a minimal contact resistance in order to prevent hot spot.