The utility model provides a cell structure of a square super capacitor or a battery. The cell structure comprises a positive plate coated with a positive active substance, a diaphragm and a negative plate coated with a negative active substance, wherein a blank area in certain width, which is not coated with the active substance, is reserved at one side edge of the positive plate and the negative plate respectively, the blank areas on the side edges of the positive plate and the negative plate are exposed at two sides of a cell body after folding or winding, the positive blank area in multilayer structure is connected with a positive lug, and the negative blank area in multilayer structure is connected with a negative lug; and the positive blank area in multilayer structure and the positive blank area in multilayer structure are double folded towards the middle of the cell body. In the unique cell structure, the size, the position, the amount and the direction for leading the lugs can be adjusted freely according to use requirements; and the cell structure is reasonable in design, simple in operation, is easy to realize, and is especially suitable for large current charging/discharging and high power sites. Meanwhile, after the positive and the negative blank areas are double folded, an unfilled space is reserved in the middle of the cell body, not only can be used as an airbag, but also can facilitate heat dissipation, so the safety and reliability of the super capacitor or the battery are improved.