The device has a battery system (7) comprising multiple cells, and a communication link including an electric isolation part (5) and a communication line (3) that is partially provided with an electromagnetic shielding (4). The communication link operatively connects two electronic units (1, 2) to enable communication between the electronic units. One of the electronic units comprises a ground potential operatively connected to a ground potential (GND1) of the battery system, where the electromagnetic shielding is operatively connected to the ground potential of the electronic unit. The electronic units are provided as a battery management unit and a cell supervisory controller, respectively. The electric isolation part is formed as an optocoupler, inductive or capacitive transmission. The communication link comprises control lines e.g. enable lines and disable lines, to respectively activate or deactivate the electronic unit.
