NOVELTY - The structure has a current collection tab layer (27) which is not exposed to a surface of the stirring junction portions that are formed by joining a press board (25), the current collection tab layer, and an electrical power collector (11b) by a friction stir welding. The stirring junction portion is provided with a space (S) extending in the electrical power collector from the side of press board. The portion of the stirring junction portions are provided for surrounding the space. The stirring junction portions are formed in the shapes of the spots.    USE - Structure for collecting current of secondary battery such as lithium ion battery. Uses include but are not limited to electronic devices such as mobile telephone and personal computer, UPS, photovoltaic and wind power generations, and vehicle such as hybrid electric vehicle (HEV), electric vehicle (EV), forklift, and shovel car.    ADVANTAGE - Since the current collection tab layer is not exposed to the surface of a stirring junction portion as all stirring junction portions are formed with a continuous plastic deformation metal, the resistance value of junction portions and the contact resistance between the electrical power collector of terminal and current collection tabs are reduced. Thus, the generation of fluctuation in the resistance value by friction stir welding is suppressed while preventing the increase of the thickness of plastic deformation metal around the edge of the stirring junction portions surrounding the space and burr generation at the edge of stirring junction portion.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for forming structure used for collecting current of secondary battery.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross sectional view of the stirring junction portion of the lithium ion secondary battery.    Electrical power collector (11b)    Press board (25)    Current collection tab layer (27)    Convex portion (45)    Space (S)