NOVELTY - The cell (2) has an electrode stack (1) disposed inside a cell housing and arranged in an electrically isolating frame. The stack has electrode foils (3) e.g. copper and aluminum foils, connected to power dissipating vanes (5) in an electrically conductive manner. The electrodes of different polarities are separated from each other in an insulating manner by a separator (4) e.g. separator foil. The vanes of same polarity are connected to each other in an electrically conductive manner to form a pole. The vanes of the pole are electrically compressed with each other and/or welded to each other.    USE - Flat cell for a battery e.g. lithium-ion-cell, of a mild hybrid vehicle.    ADVANTAGE - The power dissipating vanes of the pole are electrically compressed with each other and/or welded to each other, thus improving leak-tightness of interior of the cell housing against passage of humidity and reducing manufacturing cost of the battery. The electrode stack is arranged in the electrically isolating frame, thus saving an additional isolating arrangement and facilitating a manageability of the flat cell in a secure manner. The design of the flat cell simplifies a structure of the cell housing while inexpensive manufacturing, increases vibration safety, stability and lifespan of the battery, enables better designed space utilization within a battery case, precisely facilitates manufacturing of the flat cell by simple contact to the flat cell, improves ampacity by material-fitting contacting the power dissipating vanes, and avoids impairment of pressure-tight of the cell housing of the flat cell.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for manufacturing a flat cell of a battery.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of an electrode stack that is arranged in a frame with two flat sides arranged in the frame.    Electrode stack (1)    Flat cell (2)    Electrode foils (3)    Separator (4)    Power dissipating vanes (5)