2.2 Cell Stacking & Winding

Stacking is the process of assembling cells stacks by alternate layering of anode, separator, and cathode sheets. A common stacking method is Z-folding, where a continuous separator web is fed between electrodes inserted from both sides, forming a zig-zag structure. Electrode sheets are typically positioned using vacuum grippers for high precision. After stacking, the cell is wrapped in separator film, trimmed, and secured—preparing it for insertion into the final housing. 

Winding is the process used to winding lengths of anode, separator and cathode into a tightly wound structure known as a jelly roll. Before winding, tabs are welded to the anode and cathode, and the materials are fed into the system in a defined sequence. The jelly roll is formed around a center pin or mandrel, secured with adhesive tape, ready for insertion into the cell housing. The center pin may either be removed or retained to support heat dissipation within the cell