Method for Charging or Discharging an Exchangeable Energy Store by Means of an Electrical Device and System Comprising an Exchangeable Energy Store and an Electrical Device for Carrying out the Method

A method for charging or discharging an exchangeable energy store by means of an electrical device includes connecting a first electromechanical interface of the energy store to a further electromechanical interface of the electric device, applying a first measurement signal to a first signal contact or data contact of the further electromechanical interface without a charging or discharging current flowing, detecting a first voltage drop between the first signal contact or data contact and a first power contact of the further electromechanical interface operatively connected to the first signal contact or data contact, applying a charging or discharging current to the power contact of the further electromechanical interface, detecting again a first voltage drop between the first signal contact or data contact and the first power contact of the further electromechanical interface of the electrical device, and calculating a voltage difference between the two detected first voltage drops.