2060 20KHz 50-layer copper foil + 2mm nickel welding
Ultrasonic battery welding demonstration. Weld stacked electrode sheets, tabs and current collectors for Li-ion pouch cells and EV applications.
Here a 20 kHz machine welds through 50 layers of copper foil against 2 mm nickel in one stroke. Multi-layer stacks are the hard case: low amplitude leaves inner layers unbonded, high amplitude damages the foil edges, so the cycle is usually closed on displacement rather than time.