Provided is a laser welding method for flat wires in which side surfaces at ends of first and second flat wires coated with insulating films, the side surfaces being stripped of the insulating films, are butted together, and a laser beam is applied to end surfaces of the first and second flat wires to weld together the side surfaces. This method includes: applying the laser beam in a loop shape inside the end surface of the first flat wire to form a molten pool; and gradually increasing the diameter of a loop-shaped application trajectory of the laser beam inside the end surface of the first flat wire to allow the molten pool to reach the side surfaces.

One aspect relates to an electrode-electrical conductor system for a medical device. The system includes one or more electrically insulated wire(s) or cable(s) wherein. The electrical insulation includes electrical conductor one or more partial opening(s), which is/are arranged on one side of the wire(s) or cable(s), and one or more electrode(s), which is/are mechanically and electrically connected to the wire(s) or cable(s) via the one or more partial opening(s) arranged on one side of the wire(s) or cable(s). The mechanical and electrical connections are made by welding, pressing, swaging, adhesives, brazing, soldering and/or dimples. One aspect also relates to a method for preparing such an electrode-electrical conductor system.

A method for connecting a conductor wire to an electrode that is formed on a substrate includes placing the conductor wire on the electrode while tension is applied to the conductor wire, and soldering the conductor wire to the electrode while the conductor wire is pressed toward the substrate by a heating element.