초록 ▼

A prismatic battery with highly reliable sealing properties and its manufacturing method, wherein a negative collector is welded to one end of an electrode plate group accommodated in a prismatic case, the collector being connected to an electrode pole that functions as the negative electrode termin

A prismatic battery with highly reliable sealing properties and its manufacturing method, wherein a negative collector is welded to one end of an electrode plate group accommodated in a prismatic case, the collector being connected to an electrode pole that functions as the negative electrode terminal, and the electrode pole is fitted into a support cylinder that is provided on an upper lid for closing one open end of the case. An insulating gasket is interposed between an inner periphery of the support cylinder and an outer periphery of the electrode pole, the support cylinder being formed with at least one annular crimped portion that has an arc-shaped longitudinal cross section.

대표청구항 ▼

What is claimed is: 1. A prismatic battery comprising: a square tube case having at least one open end for accommodating an electrode plate group; a current collector of one polarity welded to one end of the electrode plate group; an electrode pole that functions as an electrode terminal connected

What is claimed is: 1. A prismatic battery comprising: a square tube case having at least one open end for accommodating an electrode plate group; a current collector of one polarity welded to one end of the electrode plate group; an electrode pole that functions as an electrode terminal connected to said current collector; a buffer that connects said current collector and said electrode pole and allows movement of said electrode pole in a horizontal direction and a vertical direction; a lid for closing said one open end of the case, the lid being formed with a support cylinder that is fitted onto the electrode pole; and an insulating gasket interposed between an inner periphery of the support cylinder and an outer periphery of the electrode pole, wherein the support cylinder is formed with at least one annular crimped portion that has an arc-shaped longitudinal cross section. 2. The prismatic battery according to claim 1, wherein the insulating gasket comprises a first gasket member and a second gasket member, the first gasket member being positioned at an area where the annular crimped portion is formed in the support cylinder, and the second gasket member being on both axial sides of the first gasket member, the second gasket member being harder than the first gasket member. 3. The prismatic battery according to claim 2, wherein secondary annular crimped portions are formed in the support cylinder at both axial ends of the area where said one annular crimped portion is formed. 4. The prismatic battery according to claim 1, wherein the buffer has a cylindrical boss protruding from a top surface, the cylindrical boss being fitted into a hole formed in a lower end of the electrode pole. 5. The prismatic battery according to claim 1, wherein the insulating gasket includes an integrally formed buffer cover for preventing contact between the buffer and the case. 6. The prismatic battery according to claim 5, further including an insulating frame for covering at least an outer peripheral part of said current collector and an exposed part of an electrode core material at the one end of the electrode plate group. 7. The prismatic battery according to claim 6, wherein the buffer cover is formed in one piece with the insulating frame. 8. The prismatic battery according to claim 1, wherein the lid has a shape that conforms to an inner periphery of the open end of the case, and includes a skirt protruding outwards from the outer peripheral edge of the lid, the lid being hermetically welded to the open end of the case by projecting laser beam from an inner side of the skirt of the lid toward the edge of the skirt to form a weld joint between the open end edge of the case and the edge of the skirt. 9. The prismatic battery according to claim 8, wherein wall thickness of the lid is thinner than wall thickness of the case. 10. The prismatic battery according to claim 8, wherein an additional reinforcing weld joint is formed by spot welding or seam welding at a position below the edges of the case and the skirt. 11. The prismatic battery according to claim 8, wherein the lid includes a plurality of bosses spaced along the length and extended over the width of the lid, the bosses protruding toward the inside of the case and being welded directly or indirectly to the electrode plate group. 12. The prismatic battery according to claim 1, wherein the square tube case is made from a cylindrical tube having open ends that are hermetically closed with the lid for closing said one open end of the square tube case and a second lid to form a battery case. 13. The prismatic battery according to claim 12, wherein the square tube case is made from the cylindrical tube by a cold drawing process. 14. The prismatic battery according to claim 12, wherein the second lid functions as a current collector and is welded to a second end of the electrode plate group, is further fitted to and hermetically welded to one open end of the square tube case. 15. The prismatic battery according to claim 1, wherein said current collector of one polarity, which is negative, is made of a nickel-plated copper plate. 16. The prismatic battery according to claim 1, wherein said current collector of one polarity, which is negative, is made of a copper plate with an oxide film formed thereon. 17. The prismatic battery according to claim 1, wherein the insulating gasket is designed to deform when pressure inside the case exceeds a predetermined level to communicate inside and outside of the case. 18. The prismatic battery according to claim 1, wherein the electrode pole includes a half-cut portion that forms a connection surface.