A method for connecting at least one wire to a contact element to facilitate connection of the wire to a power source comprising the following steps: a) preparation of the contact element which is fitted with a groove for receiving at least one wire; b) insertion of the wire into the groove of the contact element; c) lowering an electrode onto the contact element; and d) heating of the area around the groove by means of the electrode while simultaneously deforming the area around the groove thereby embedding the wire lying in said groove.