ELECTRIC ENERGY STORE

The invention relates to an electric energy store, comprising contact electrodes (2) at least for tapping an electric useful voltage, a plurality of energy storage cells (41, 42, 43, 44) which are connected to the contact electrodes via a common contacting unit (6) by means of an interconnected control unit (10) for influencing at least one discharge process of the individual energy storage cells (41, 42, 43, 44). The invention is characterized in that at least one readable and writable data memory (7') which can be connected via a detachable interface (9) directly or indirectly to the control unit (10) is integrated in each energy storage cell (41, 42, 43, 44), a unit is associated with each energy storage cell (41, 42, 43, 44) that detects the current charge state of the energy storage cell (41, 42, 43, 44) dynamically, said unit dynamically creating charge state information on the energy storage cell (41, 42, 43, 44) and transmitting said information to the readable and writable data memory (7') for creating and storing a charge state history. Each energy storage cell (41, 42, 43, 44) comprises electric connecting contacts (5) that can be detachably connected to the contacting unit (6).