Abstract: Provided is art that allows joining an external conductive member and a bus bar more stably. A method for producing a secondary battery disclosed herein has: an attachment step; an arrangement step; a covering step; and, a joining step. The external conductive member has a recess sunk from the upper surface, around a through-hole. In the joining step, the external conductive member and the terminal are joined in a state where an edge portion of a cover member is disposed between a planned joint portion, and an outer peripheral edge of the recess, in a cross-sectional view along a direction of penetration into the through-hole.

Abstract: According to the present disclosure, a secondary battery in which a gas discharge valve has excellent operational stability is provided. A battery case of the secondary battery disclosed herein includes a flat rectangular sealing plate, and a gas discharge valve provided in the sealing plate. In addition, in the secondary battery, a thickness T1 of the sealing plate, a length L1 of a short side of the sealing plate, a length L2 of a long side of the sealing plate, and a length L3 of the gas discharge valve in a short side direction satisfy expression (1) represented by T1/L1?0.1, expression (2) represented by L2/L1?6, and expression (3) represented by L3/L1?0.4. As a result, when an internal pressure of the case rises to a desired pressure, the sealing plate is easily bent and deformed, so that the gas discharge valve can be stably operated by the bending deformation.

Abstract: According to the present disclosure, there is provided a sealing plate equipped with a gas discharge valve that reduces processing load and work hardening during molding. A gas discharge valve of a sealing plate 1 disclosed herein has a flat plate-shaped base portion and a protruding portion protruding from a first surface of the base portion in a first direction, an annular thin-walled portion having a thickness smaller than the thickness of the protruding portion is provided around the protruding portion, and a first surface of the thin-walled portion is substantially on the same surface as the first surface of the base portion. In the gas discharge valve having the above configuration, the total amount of metal that is plastically deformed is reduced by limiting the formation region of the thin-walled portion to the periphery of the protruding portion.

Abstract: The present disclosure provides a sealing plate including a gas release vent capable of suppressing scattering of a metallic fragment during activation. A gas release vent of a sealing plate disclosed herein includes: a base portion with a flat plate shape; a thin portion which is thinner than the base portion; a groove portion formed in the thin portion; and a valve element formed inside the groove portion. In addition, the groove portion has a remaining portion which is a region with a larger remaining thickness as compared to another region of the groove portion. The remaining portion of the groove portion is formed in a region including one intersection point among two intersection points where a straight line which passes a center of the gas release vent and which extends in a short-side direction of the sealing plate intersects the groove portion with the approximately annular shape.

Abstract: A battery disclosed herein includes: electrode bodies: an outer package which has an opening and which houses the electrode bodies, a sealing plate which seals the opening of the outer package and which has a through-hole and a recessed portion provided around the through-hole on a surface of a side opposing the electrode bodies; and a sealing member which seals the through-hole of the sealing plate. The sealing member has an inserted portion having been inserted to the through-hole and an enlarged diameter portion which extends from the inserted portion to inside of the outer package and which is formed with a larger diameter than the inserted portion. At least a part of the enlarged diameter portion is arranged inside the recessed portion of the sealing plate.

Abstract: [Problem] There is provided a sealed cell with no possibility of liquid leakage without sacrificing volume energy density. [Measures to solve the problem] The sealing body is characterized as follows: the sealing body for a sealed cell comprises a substantially rectangular-shaped sealing plate having a through hole and/or a thinner portion that is thinner than other portions, and an electrode external terminal attached to the through hole and/or the thinner portion; and the periphery of the sealing body in the vicinity of the terminal plate is thicker than other portions. The thicker portion is 0.1 to 0.4 mm thicker than the other portions, and the width of the thicker portion is preferably 0.1 to 0.5 mm.

Abstract: A sealed battery uses an outer can 15 with an opening and a sealing plate 16 provided with a rising part which rises perpendicularly from the middle of a flange on the entire circumference of or a part of the fitted face with the battery outer can 15. A production method thereof includes inserting the sealing plate 16 into the opening of the battery outer can 15 so that the top faces of both the battery outer can 15 and the flange of the sealing plate 16 are substantially in the same plane, and irradiating the fitted part of the opening of the battery outer can 15 and the sealing plate 16 with a high energy beam for welding.

Abstract: A method for manufacturing a sealed battery for the invention uses an outer can 15 with an opening and a sealing plate 16 provided with a rising part which rises perpendicularly from the middle of a flange on the entire circumference of or a part of the fitted face with the battery outer can 15. The method includes inserting the sealing plate 16 into the opening of the battery outer can 15 so that the top faces of both the battery outer can 15 and the flange of the sealing plate 16 are substantially in the same plane, and irradiating the fitted part of the opening of the battery outer can 15 and the sealing plate 16 with a high energy beam for welding.

Abstract: A negative electrode terminal includes an outer terminal of a solid flat rivet shape and an inner terminal of a hollow flat rivet shape. A hollow axle portion of the inner terminal is inserted in a first insulating member, an opening bored in a sealing plate, and a second insulating member so as to be insulated from the sealing plate. A columnar axle portion of the outer terminal is inserted into the hollow axle portion of the inner terminal and crimped thereto, so that a radially bulge-deformed portion is formed in an intermediate portion of the columnar axle portion. The hollow axle portion deforms into a shape matching the radially bulge-deformed portion and is crimped to the columnar axle portion, and its tip is curling-formed to match a curved surface between a brim portion and the columnar axle portion of the outer terminal.

Abstract: [Problem] There is provided a sealed cell with no possibility of liquid leakage without sacrificing volume energy density. [Measures to solve the problem] The sealing body is characterized as follows: the sealing body for a sealed cell comprises a substantially rectangular-shaped sealing plate having a through hole and/or a thinner portion that is thinner than other portions, and an electrode external terminal attached to the through hole and/or the thinner portion; and the periphery of the sealing body in the vicinity of the terminal plate is thicker than other portions. The thicker portion is 0.1 to 0.4 mm thicker than the other portions, and the width of the thicker portion is preferably 0.1 to 0.5 mm.

Abstract: A sealed cell having a safety mechanism is provided. The safety mechanism has a non-resealable valve structure formed in a sealing plate that seals the cell. The valve structure is broken as soon as the internal pressure reaches or exceeds a predetermined value so as to permit the internal gas to be released outside. The valve structure has at least one dome protruding toward the interior of the cell, which in turn has at the periphery thereof a break groove for facilitating the breakage of the valve structure. This makes the valve structure highly responsive to the internal pressure and causes to form a break-opened orifice of a sufficient area at the time of operation in response to the increased internal pressure. The valve structure is not unnecessarily broken by the impacts of, for example, dropping. As a result, the safety of the sealed cell is significantly improved.

Abstract: A method for manufacturing a sealed battery for the invention uses an outer can 15 with an opening and a sealing plate 16 provided with a rising part which rises perpendicularly from the middle of a flange on the entire circumference of or a part of the fitted face with the battery outer can 15. The method includes inserting the sealing plate 16 into the opening of the battery outer can 15 so that the top faces of both the battery outer can 15 and the flange of the sealing plate 16 are substantially in the same plane, and irradiating the fitted part of the opening of the battery outer can 15 and the sealing plate 16 with a high energy beam for welding.

Abstract: A cell according to the present invention comprises a positive electrode, a negative electrode, an electrolyte solution, and an outer casing, wherein the outer casing comprises a valve plate 30 having a thickness, an annular-shaped break groove 4 formed on the valve plate, and one or more of break aiding grooves 1 in the inner area of the break groove, and wherein the break aiding groove comprises such configurations that remaining thickness of the valve plate at the break aiding groove is thicker than remaining thickness of the valve plate at the break groove, and at least one end of the break aiding groove is connected with the break groove. In a cell provided with a valve plate which is a safety valve 9 comprising the break groove and the break aiding groove, the safety valve operates smoothly and releases a gas inside the cell quickly, and resistance to dropping impact is improved.

Abstract: A sealed cell having a safety mechanism is provided. The safety mechanism has a non-resealable valve structure formed in a sealing plate that seals the cell. The valve structure is broken as soon as the internal pressure reaches or exceeds a predetermined value so as to permit the internal gas to be released outside. The valve structure has at least one dome protruding toward the interior of the cell, which in turn has at the periphery thereof a break groove for facilitating the breakage of the valve structure. This makes the valve structure highly responsive to the internal pressure and causes to form a break-opened orifice of a sufficient area at the time of operation in response to the increased internal pressure. The valve structure is not unnecessarily broken by the impacts of, for example, dropping. As a result, the safety of the sealed cell is significantly improved.

Abstract: A cell according to the present invention comprises a positive electrode, a negative electrode, an electrolyte solution, and an outer casing, wherein the outer casing comprises a valve plate 30 having a thickness, an annular-shaped break groove 4 formed on the valve plate, and one or more of break aiding grooves 1 in the inner area of the break groove, and wherein the break aiding groove comprises such configurations that remaining thickness of the valve plate at the break aiding groove is thicker than remaining thickness of the valve plate at the break groove, and at least one end of the break aiding groove is connected with the break groove. In a cell provided with a valve plate which is a safety valve 9 comprising the break groove and the break aiding groove, the safety valve operates smoothly and releases a gas inside the cell quickly, and resistance to dropping impact is improved.

Abstract: A cell safety valve which has a thin valve plate formed on a sheet-shaped sealing plate for sealing the cell such that if the inner pressure of the cell exceeds a predetermined value, the valve plate breaks to release a gas in the cell to the outside, in which the valve plate has a dome-shaped dome portion formed thereon and, at its middle or near it, a break groove formed for facilitating the breaking of the valve. By this construction, it is possible to prevent the electrolyte from leaking while reducing the cell-to-cell difference in the operating pressure of the safety valve and ensuring a sufficient open area at the time of the operations of the safety valve.

Abstract: A cell safety valve which has a thin valve plate formed on a sheet-shaped sealing plate for sealing the cell such that if the inner pressure of the cell exceeds a predetermined value, the valve plate breaks to release a gas in the cell to the outside, in which the valve plate has a dome-shaped dome portion formed thereon and, at its middle or near it, a break groove formed for facilitating the breaking of the valve.