Method for Controlling a Charging or Discharging Current of a Removable Battery Pack and/or an Electrical Device and System for Carrying out the Method

A system comprising:

• a removable battery pack including a first monitoring unit and a first electromechanical interface having a first plurality of electrical contacts;
• and
• an electrical device including an evaluation unit and a second electromechanical interface having a second plurality of electrical contacts,
• wherein in each of the first and second plurality of electrical contacts (i) a first electrical contact is configured as an energy supply contact supplied with a first reference potential, (ii) a second electrical contact is configured as an energy supply contact supplied with a second reference potential, and (iii) a third electrical contact is configured as a signal or data contact, and
• wherein the system is configured to control a charging or discharging current of the removable battery pack and/or the electrical device using the first monitoring unit, the system configured to:
• monitor a defined control potential of the signal or data contact between the removable battery pack and the electrical device using the evaluation unit, and
• change the defined control potential using the first monitoring unit when the first monitoring unit has identified a fault state.