The feedthrough (3) has a hollow conductive flange (7) that comprises a cavity and a flange case. A contact portion (5) positioned in the cavity is electrically insulated and sealed with respect to the flange. The flange and contact portion are connected to cathode lug and cuboid lead respectively. A circumferential section of flange is comprised with a tangentially extending gap. The gap is delimited on one side using the flange case and on another side using a tab. An independent claim is included for electrical functional unit.
