Method for Detecting Electrical Fault States in a Removable Battery Pack and System for Carrying out the Method

A method detects electrical fault states of a plurality of energy storage cells interconnected with one another in series and/or in parallel in a removable battery pack using a first monitoring unit integrated in the removable battery pack and a multiplexer measuring apparatus, which can be controlled by the first monitoring unit to sequentially measure cell voltages of the energy storage cells. A further monitoring unit sends a command to the first monitoring unit to control the multiplexer measuring apparatus, and is provided in an electrical device, in particular a charging device, a diagnostic device or an electrical consumer, that can be electrically connected to the removable battery pack.