The invention relates to a rechargeable battery discharge device (10) for discharging rechargeable batteries (20), comprising (a) a first rechargeable battery connection (12.1) for connecting a first rechargeable battery (20.1), (b) a second rechargeable battery connection (12.2) for connecting a second rechargeable battery (20.2), (c) at least one third rechargeable battery connection (12.3) for connecting a third rechargeable battery (20.3), and (d) a load connection (14) for a load (16) for dissipating an electric output upon discharging the rechargeable batteries (20). According to the invention, (e) a discharge circuit (18) is provided which has (i) a first short circuit switch (24.1), (ii) a first voltage meter (22.1) designed to measure a first rechargeable battery voltage (U20.1) which drops across the first rechargeable battery connection (12.1), (iii) a second short circuit switch (24.2), (iv) a second voltage meter (22.2) designed to measure a second rechargeable battery voltage (U2o.2) which drops across the second rechargeable battery connection (12.2), (v) a third short circuit switch (24.3), (vi) a third voltage meter (22.3) designed to measure a third rechargeable battery voltage (U20.3) which drops across the third rechargeable battery connection (12.3), and (vii) a control unit (27), wherein (f) the control unit (27) is designed to automatically carry out a method with the steps of: (i) detecting the respective rechargeable battery voltage (U20.i) for all of the voltage meters (22.i), (ii) if the respective rechargeable battery voltage (U20.i) exceeds a specified minimum voltage (Umin), connecting the corresponding rechargeable battery (20.i) into a series circuit with at least one other rechargeable battery, and (iii) if the respective rechargeable battery voltage (U20.i) does not exceed the minimum voltage (Umin), removing the corresponding rechargeable battery (20.i) from the series circuit using the corresponding short circuit switch.