Abstract: The invention discloses a high-capacity cylindrical lithium ion battery. Tab-position end face is shaped; a high frequency oscillation and pressure are applied on to make the foil bodies softened in the scope of 0.1-6.5 mm. At the instant of high-frequency oscillation, the rigidity of the foil body is greatly decreased; and the foil bodies are mutually wound and compressed together, so that the weight density of the foil body in unit volume is increased and meanwhile, the rigidity of the compressed foil body at the Tab-position end face is greatly increased, thereby laying a firm foundation for laser welding of the 1 Tab-position end face and a current collector, increasing a laser welding effective area of the Tab-position end face and the current collector, and improving the welding strength.