Cell assembly involves multiple critical steps to ensure proper packaging, electrolyte filling, and sealing of battery cells. In pouch cell assembly, the current collector foils—copper for the anode and aluminum for the cathode—are welded to the cell tabs using ultrasonic or laser welding. The cell stack is then positioned in a deep-drawn pouch foil, which is sealed on three sides, leaving one side open for electrolyte filling. Electrolyte filling follows the packaging process, where the electrolyte is introduced under vacuum using a high-precision dosing needle. This step includes both filling and wetting, where alternating vacuum and inert gas pressure activate the capillary effect within the cell. The process is repeated multiple times based on the cell type before the pouch foil is vacuum-sealed. For prismatic and cylindrical cells, the jelly roll is inserted into a robust metal housing. In prismatic cells, the edges of the jelly roll are compressed, fixed, and welded to the battery lid. An insulation foil protects the jelly roll during insertion, and the housing is sealed using laser welding. In cylindrical cells, a bottom insulator is inserted first, followed by the jelly roll, and the anode and cathode current collectors are welded to the housing and lid, respectively. An insulation ring is placed between the jelly roll and the lid before final sealing. Electrolyte filling for prismatic and cylindrical cells occurs after the jelly roll is housed, following the same vacuum-filling and wetting process. The cells are then sealed through crimping, beading, or welding, ensuring their integrity for further processing.