NOVELTY - The control device (3) has an error position detecting apparatus (6) which detects the incorrect position of the memory (2). A memory device (13) stores the duration of the incorrect position. A signaling device (14) provides an incorrect position signal (F), if the duration of the fault location is greater than or equal to a predetermined minimum duration. The position sensors (7,8) detect the incorrect position. The position sensors are designed as acceleration sensors that detect the accelerations in the amount of earth's gravity.    USE - Control device for checking functionality of memory of electric power of battery of battery system mounted in motor car (all claimed).    ADVANTAGE - The hermetically sealed construction of battery is achieved, so that electrolyte fluids or moisture to penetrate into the memory can be prevented. Since the position sensor is intended only to identify undesirable locations and no other mechanical events, the position sensor can be formed easily and inexpensively. The mechanical safety of the unloading switch in the closed switch position works independently from a power supply of the unloading switch and thus ensures the closed switching position of the unloading switch reliably. The storage of electrical energy of the discharge current can be removed to avoid overloading of the damaged battery system, and the discharge current is less than or equal to maximum load current removable from the memory. The switch controller is integrated in a battery management system, thereby reducing the complexity of the battery system. The switch controller can be formed separately, and irrespective of the battery management system in order to avoid transmission of false states of battery management system to the switch controller, so that the safety of battery system can be increased.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) unloading device; and    (2) method for controlling functionality of memory of electric power of battery.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the battery system.    Memory (2)    Control device (3)    Error position detecting apparatus (6)    Memory device (13)    Signaling device (14)    Incorrect position signal (F)