Abstract: A method and associated device for joining a battery cell tab to a plurality of foils associated with a plurality of electrodes of a battery cell are described. This includes arranging the plurality of foils in a stack, and joining, via a first joining device, the plurality of foils, wherein the first joining device defines a joining region. A portion of the battery cell tab is arranged on the plurality of foils, and joined, via a second joining device, to the plurality of foils. The second joining device generates a weld joint that is encompassed within the joining region defined by the first joining device. In doing so, weld quality and strength of internal welds in a battery cell may be improved by reducing the occurrence of porosities and cracks in the foil/tab weld joints.

Abstract: A method and associated device for joining a battery cell tab to a plurality of foils associated with a plurality of electrodes of a battery cell are described. This includes arranging the plurality of foils in a stack, and joining, via a first joining device, the plurality of foils, wherein the first joining device defines a joining region. A portion of the battery cell tab is arranged on the plurality of foils, and joined, via a second joining device, to the plurality of foils. The second joining device generates a weld joint that is encompassed within the joining region defined by the first joining device. In doing so, weld quality and strength of internal welds in a battery cell may be improved by reducing the occurrence of porosities and cracks in the foil/tab weld joints.

Abstract: A welding assembly includes a sonotrode, cleaning station, and controller. The controller periodically commands clamping of the sonotrode onto the cleaning block, and a transmission of ultrasonic energy into the cleaning block for a calibrated duration sufficient for removing residual amounts of metal from welding pads of the sonotrode. The cleaning block may include an aluminum bar coated with a polymeric material, e.g., porous polyethylene silica or alumina composite. A thin sacrificial layer of an anti-adhesion material, e.g., colloidal silica, may be periodically applied to the welding pads, particularly after a transition from welding a first metal to welding a second metal. The sacrificial layer may be applied via a sponge, a saturated surface, or spraying.

Abstract: A welding assembly includes a sonotrode, cleaning station, and controller. The controller periodically commands clamping of the sonotrode onto the cleaning block, and a transmission of ultrasonic energy into the cleaning block for a calibrated duration sufficient for removing residual amounts of metal from welding pads of the sonotrode. The cleaning block may include an aluminum bar coated with a polymeric material, e.g., porous polyethylene silica or alumina composite. A thin sacrificial layer of an anti-adhesion material, e.g., colloidal silica, may be periodically applied to the welding pads, particularly after a transition from welding a first metal to welding a second metal. The sacrificial layer may be applied via a sponge, a saturated surface, or spraying.