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.

Abstract: A lithium ion battery containing conducting materials comprises a positive electrode, a negative electrode, a separator, an electrolyte, adhesives and sealing materials. The conducting materials in the positive electrode comprise metal carbides, metal borides or metal nitrides. The conducting materials in the negative electrode comprise metal carbides, metal borides or metal nitrides. The metal carbide is titanium carbonitride, tungsten carbide or titanium carbide, vanadium carbide, tantalum carbide, and eutectic of tungsten carbide and titanium carbide. The metal boride is molybdenum boride, tungsten boride or vanadium boride. The metal nitride is titanium nitride, tungsten nitride or tantalum nitride. The conducting materials in the positive electrode may also comprise powdered metals. The conducting materials in the negative electrode comprise powdered metals. The powdered metal is nickel powder, copper powder or chromium powder.

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.