Abstract: The present invention relates to a silicon-carbon composite negative electrode active material, a negative electrode including the same, and a secondary battery, wherein the silicon-carbon composite negative electrode active material includes a core containing SiOX (0?X<2), a carbon layer covering at least a portion of the surface of the core, a carbon nanotube structure positioned on the carbon layer, and a polyvinylidene fluoride coating at least a portion of the carbon nanotube structure, wherein the carbon nanotube structure has a structure formed by arranging and bonding 2 to 5,000 single-walled carbon nanotube units side by side, and a portion of the carbon nanotube structure is bonded to the carbon layer.

Abstract: A button-type secondary battery according to the present disclosure includes: an electrode assembly; a lower can configured to accommodate the electrode assembly; an upper can coupled to an opening of the lower can; a gasket configured to insulate a coupling portion between the lower can and the upper can; and a center part provided at a core portion of the electrode assembly, wherein the center part includes: a center pin inserted into the core portion of the electrode assembly; and an upper plate provided with an upper cover surface provided on an upper end of the center pin to protect an upper portion of the electrode assembly, wherein an edge of the upper cover surface is provided to be supported on an inner wall of the lower can.

Abstract: The present invention relates to a welding apparatus for manufacturing a secondary battery and a welding method using the same, which are capable of preventing deformation of a product due to a pressure applied in all directions or non-uniform welding due to non-uniform pressing to a cover during a process of sealing and fixing the cover to an opening of a main body casing at the time of manufacturing a secondary battery.

Abstract: A button-type secondary battery includes: a lower can configured to operate as a first electrode terminal; an upper can coupled to the lower can to surround the lower can and configured to operate as a second electrode terminal; and a gasket between the lower can and the upper can. A recessed lower insertion groove and a recessed upper insertion groove are defined in a surface of the lower can and a surface of the upper can, which are in close contact with the gasket, respectively. The lower insertion groove and the upper insertion groove are spaced apart from each other so as not to face each other.

Abstract: A button-type secondary battery includes a lower can; an upper can is coupled to the lower can; an electrode assembly is on the lower can in an accommodation space defined between the lower can and the upper can. The lower can includes a first planar part, on which the electrode assembly is seated, and a first sidewall disposed vertically along a circumference of the first planar part such that a concave portion is defined in the first sidewall. The upper can includes a second planar part, which has an area that covers an opened top surface of the lower can, and a second sidewall disposed vertically along a circumference of the second planar part such that a convex portion is on an inner surface of the second sidewall. When the sidewall is coupled to be placed outside the first sidewall, the convex portion is fitted into the concave portion.

Abstract: A button-type secondary battery includes an electrode assembly; a lower can into which the electrode assembly is disposed; and an upper can configured to cover an opening of an upper end of the lower can. A beading part recessed inward is disposed at an upper portion of the lower can. The upper end of the lower can disposed above the beading part has a bent shape and configured to surround an edge end of the upper can so that the upper can and the lower can are coupled to each other.

Abstract: A method for manufacturing a secondary battery includes preparing a lower can having an accommodation part to accommodate an electrode assembly, and an upper cover covering an upper opening of the lower can; gripping an end of a lower can circumferential portion and an end of an upper cover circumferential portion at upper and lower portions using upper and lower jigs to weld the lower can circumferential portion extending outward from an edge of the accommodation part to the upper cover circumferential portion that is a circumferential area of the upper cover; and irradiating a laser onto a bonding portion at which the lower can circumferential portion and the upper cover circumferential portion are welded to each other. In the irradiating, a height of the accommodation part is higher than a height of the end of the lower can circumferential portion.

Abstract: A button-type secondary battery includes an electrode assembly; a lower can into which the electrode assembly is disposed; and an upper can configured to cover an opening of an upper end of the lower can. A beading part recessed inward is provided in an upper portion of the lower can. An end of the upper can has a bent shape so the upper can and the lower can are coupled to each other while an end point of the end of the upper can is inserted into the beading part.

Abstract: A button-type secondary battery includes an electrode assembly; a lower can in which the electrode assembly is disposed and on which a first screw thread is defined on an outer circumferential surface thereof; an upper can which is configured to cover an opening of an upper end of the lower can and on which a second screw thread corresponding to the first screw thread is defined on an inner circumferential surface thereof; and an insulator interposed between the upper can and the lower can to prevent the upper can and the lower can from being electrically short-circuited with each other. The electrode assembly is formed by horizontally stacking a plurality of first electrodes, a separator, and a second electrode. A first electrode tab extending to be connected to each of the first electrodes of the electrode assembly is in contact with the upper can.

Abstract: A button-type secondary battery includes an electrode assembly; a lower can in which the electrode assembly is disposed and on which a first screw thread is defined on an outer circumferential surface thereof; an upper can which is configured to cover an opening of an upper end of the lower can and on which a second screw thread corresponding to the first screw thread is defined on an inner circumferential surface thereof; and an insulator interposed between the upper can and the lower can to prevent the upper can and the lower can from being electrically short-circuited with each other, wherein an electrode tab extending from an electrode of the electrode assembly is in contact with the upper can.

Abstract: A method for manufacturing a secondary battery according includes accommodating an electrode assembly, in which electrodes and separators are alternately stacked, in a can type battery case; primarily injecting an electrolyte through an injection hole; applying a pressure to the battery case while performing a formation process in a state in which the injection hole is opened; secondarily injecting the electrolyte through the injection hole after performing the formation process, and closing the injection hole.

Abstract: The present invention relates to a button-type secondary battery including: a lower can serving as a first electrode terminal; an upper can coupled to surround the lower can and serving as a second electrode terminal; and a gasket provided between the lower can and the upper can, wherein a recessed lower insertion groove and a recessed upper insertion groove are formed in a surface of the lower can and a surface of the upper can, which are in close contact with the gasket, respectively, the lower insertion groove and the upper insertion groove are spaced apart from each other so as not to face each other, and a sealing protrusion having a closed curve shape and being in close contact with the lower can and the upper can to increase in sealing force is formed on the gasket.

Abstract: A button-type secondary battery includes an electrode assembly in which electrodes and a separator are layered and wound, electrode tabs having different polarities protrude from top and bottom surfaces of the electrode assembly, respectively; a can including a bottom part with the electrode assembly disposed thereon and connected to one electrode tab, and a sidewall vertically extending along a circumference of the bottom part around the electrode assembly; and a top cap assembly with a terminal part connected to the other electrode tab and a plate coupled to be insulated from the terminal part and having an edge coupled to an upper end of the sidewall such that the top cap assembly is coupled to the can to close the can. An end of an edge of the plate is welded to be coupled after being seated on a point that meets the upper end of the sidewall.

Abstract: The present invention relates to a button-type secondary battery including: an electrode assembly; a lower can provided with an accommodation part having an accommodation groove for accommodating the electrode assembly in a top surface thereof, a connection part extending outward from an upper end of the accommodation part, and a bent part extending from a front end of the connection part to a lower side of the accommodation part; an upper can provided with a cover part disposed on a top surface of the accommodation part to finish the accommodation groove and a bonding part formed along an edge surface of the cover part and bonded to the bent part; and a gasket provided between the lower can and the upper can, wherein a recessed lower insertion groove and a recessed upper insertion groove are formed in the bent part of the lower can and the bonding part of the upper can, which are in close contact with the gasket, respectively, and the lower insertion groove and the upper insertion groove are disposed to be s

Abstract: A button-type secondary battery includes an electrode assembly in which a negative electrode, a separator, and a positive electrode are layered wound in a state of being layered; a lower can in which the electrode assembly is mounted, and a space portion is defined as a surplus space in addition to a space in which the electrode assembly is mounted; an upper can coupled to the lower can to close the lower can in a state in which the electrode assembly is mounted in the lower can, and an electrolyte is injected; and a swelling member mounted in the lower can in a state of being coupled to an outer surface of the electrode assembly. When the electrolyte is injected, the swelling member absorbs the electrolyte to be expanded in volume within the space portion.

Abstract: A button-type secondary battery includes an electrode assembly; a lower can configured to accommodate the electrode assembly; an upper can coupled to an opening of the lower can; a gasket configured to electrically insulate the lower can and the upper can from each other; a first tab part configured to connect a first electrode of the electrode assembly to the lower can; and a second tab part configured to connect a second electrode of the electrode assembly to the upper can. The second tab part includes a second electrode tab and a second lead tab. The second electrode tab is connected to the second electrode, and the second lead tab connects the second electrode tab to the upper can.

Abstract: A button-type secondary battery includes an electrode assembly having a first electrode with a first electrode tab and a second electrode with a second electrode tab; a can accommodating the electrode assembly and to which the first electrode tab is connected; a top cap coupled to an opening of the can and to which the second electrode tab is connected; and a first insulation member insulating the first electrode tab. The first electrode tab includes a first coupling surface coupled to the first electrode and a second coupling surface extending from the first coupling surface and coupled to the can. The first insulation member includes a first insulator attached to an outer circumferential surface of the electrode assembly to cover the first coupling surface, and a second insulator horizontally extending from an upper end of the first insulator toward a top surface of the electrode assembly.

Abstract: A button-type secondary battery includes an electrode assembly including a first separator, a negative electrode, a second separator, and a positive electrode that are sequentially stacked and wound, wherein ends of the first separator and the second separator are disposed closer to a center of the wound electrode assembly than ends of the positive electrode and the negative electrode; an electrolyte; and a can in which the electrode assembly and the electrolyte are accommodated. In the electrode assembly, an expansion member is attached to at least one central end of the first separator or the second separator, and the expansion member is expanded by absorbing the electrolyte.

Abstract: A button-type secondary battery according to the present disclosure includes: an electrode assembly; a lower can configured to accommodate the electrode assembly; an upper can coupled to an opening of the lower can; a gasket configured to insulate a coupling portion between the lower can and the upper can; and a center part provided at a core portion of the electrode assembly, wherein the center part includes: a center pin inserted into the core portion of the electrode assembly; and an upper plate provided with an upper cover surface provided on an upper end of the center pin to protect an upper portion of the electrode assembly, wherein an edge of the upper cover surface is provided to be supported on an inner wall of the lower can.

Abstract: A button-type secondary battery includes a lower can having a first sidewall in a vertical direction along a circumference of a first flat portion; an upper can having a second sidewall in a vertical direction along a circumference of a second flat portion, wherein the upper can is coupled to the lower can so that the second flat portion faces the first flat portion; an electrode assembly in an inner space between the lower can and the upper can; and a gasket between the second sidewall and the first sidewall to prevent the upper and lower cans from contacting. The second sidewall comprises a distant end that is bent to surround an edge configured to connect the first flat portion to the first sidewall and is below the first flat portion. The gasket extends between the distal end and the first flat portion.