SECONDARY BATTERY INCLUDING LAYERED WELDING ZONE HAVING PTC-CHARACTERISTICS AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A secondary battery is provided to simplify manufacturing process by giving PTC properties to welded part where an electrode tap and a lead are weld-combined without addition of separate devices or elements, and to restrict current flow when the temperature of the battery is increased. CONSTITUTION: A secondary battery comprises: an electrode assembly in which a positive electrode plate with a positive electrode tap(400), a negative electrode plate with a negative electrode tap, and a separator are cross-stacked; a pouch exterior in which the electrode assembly is accepted; and a positive and a negative leads(600) electrically conjugated by being welded to the positive and the negative electrode taps respectively. In a welded part in which the positive and the negative electrode taps are weld-conjugated, on at least one welded part of the positive electrode tap, the negative electrode tap, the positive electrode lead, and the negative electrode lead, a PTC coating layer is coated in advance, and welding is conducted.