Abstract: A charging device controls charging of rechargeable batteries or accumulators (4), which include individual cells (4), having a charging unit (2), by which electrical energy can be applied to the individual cells (5) during the charging procedure. A control unit (3) is used to control the procedure of charging the accumulator (4). A balance controller is used to balance the charging and/or discharging of the individual cells (5) of the accumulator in relation to one another. A connection device is used to electrically connect the cells (5) to the charging device (1) in a detachable manner. The charging device (1) is equipped with a wireless ID reader, which makes it possible to wirelessly read the ID (identification) of an accumulator (4) equipped with an ID label, and a data file (11) for each ID can be generated in the charging device (1).