Method of manufacturing a wiring material

A method of manufacturing a wiring material having a connecting terminal electrically connected to a circular shaped single line conductor, comprising the steps of:

• bending a single line conductor to have a circular shape;
• extending both ends of the single line conductor that is bent in parallel;
• forming a tube-shaped section having a circular cross section at the connecting terminal for accommodating the both ends of the single line conductor;
• inserting the both ends of the single line conductor into the tube-shaped section;
• and
• conducting a resistance welding by energizing welding electrodes from the outer periphery of the tube-shaped section, in a state where a portion of the tube-shaped section between the ends of the single line conductor is pushed by the welding electrode into a space formed between the ends of the single line conductor and an inner periphery surface of the tube-shaped section contacts with the both ends of the single line conductor to electrically connect the connecting terminal with the both ends of the single line conductor.