A cell structure that can improve heat dissipation and the vibration-proofing nature of a cell without using a cooling medium while keeping the rigidity and the discharge current quantity of the cell includes at least one electrode having a positive pole active material layer, a current collector and a negative pole active material layer. The cell structure also includes a separator provided between each electrode; and a casing. The cell structure satisfies the inequality:.times.>.times. ##EQU00001## wherein b (mm) indicates a short-side length of the electrode, S (m.sup.2) indicates an electrode area, c (mm) indicates a cell structure thickness and 1000 (m.sup.2/mm) is a constant. The separators have a different Shore A hardness and the separator having the lowest Shore A hardness is placed at a center of the cell structure.