Abstract: The present invention relates to a secondary battery. The secondary battery includes a can configured to accommodate an electrode assembly; and a cap assembly bonded to an opening of the can. The cap assembly includes an upper cap provided in the opening and connected to an electrode tab of the electrode assembly and a lower cap configured to bond the upper cap to the opening. The lower cap includes a first bonding part bonded to a bottom surface of the upper cap to support the upper cap and a second bonding part formed on an outer circumferential surface of the first bonding part to fix the upper cap while being bonded to the upper cap.

Abstract: A system for manufacturing an electrode for a secondary battery is disclosed herein. In an embodiment, the system for manufacturing the electrode for the secondary battery comprises a supply roller for supplying a collector having a long sheet shape; an electrode active material coating device for applying an electrode active material to a surface of the collector supplied by the supply roller to manufacture an unfinished electrode; a rolling roller for rolling a surface of the unfinished electrode and adjusting a thickness of the electrode active material to manufacture a finished electrode; and an electrode quality inspection device for inspecting quality of the electrode through a surface roughness value of the rolling roller, a surface roughness value of the surface of the electrode, and a rolling load value of the rolling roller.

Abstract: The present disclosure relates to a secondary battery electrode, a manufacturing method for the same, and an electrode assembly, and more particularly, to a secondary battery electrode, a manufacturing method for the same, and an electrode assembly having improved stability. In accordance with an exemplary embodiment, a secondary battery electrode includes a current collector that extends in one direction, a first active material layer provided on one surface of the current collector and including a first inclined portion and a first protruding portion, and a second active material layer provided on the other surface of the current collector and including a second inclined portion and a second protruding portion. In particular, a position of the second protruding portion is controlled on the second active material layer to be disposed at a position that is not directly opposite to the first inclined portion with respect to the current collector.

Abstract: A system for manufacturing an electrode for a secondary battery is disclosed herein. In an embodiment, the system for manufacturing the electrode for the secondary battery comprises a supply roller for supplying a collector having a long sheet shape; an electrode active material coating device for applying an electrode active material to a surface of the collector supplied by the supply roller to manufacture an unfinished electrode; a rolling roller for rolling a surface of the unfinished electrode and adjusting a thickness of the electrode active material to manufacture a finished electrode; and an electrode quality inspection device for inspecting quality of the electrode through a surface roughness value of the rolling roller, a surface roughness value of the surface of the electrode, and a rolling load value of the rolling roller.

Abstract: A cylindrical lithium secondary battery according to the present invention can reduce gas explosion by preventing gas concentration from being concentrated only on the upper top cap vent by increasing the gas spouting passage through which the inner gas of the can is spouted by forming a rupture portion of a material different from that of the can member on a part of the cylindrical can member, and when the inside or outside of the battery is exposed to a high temperature, by making, a shape-based alloy member, which causes cracking of the can member by deformation, included a part of the can member, the gas is discharged through the can vent by the cracking of the can member to prevent explosion before the tap cap safety vent operates by the internal air pressure, and ignition that may be caused by heating by internal or external heat may be prevented.

Abstract: An apparatus for manufacturing an electrode includes a supply member configured to supply a collector; an attachment member configured to attach a coating paper to a top surface of the collector supplied by the supply member at set intervals; and a first injection member that operates to inject an electrode active material to the top surface of the collector, thereby forming a first coating layer when the collector passes through a first section and stops operating so as not to inject the electrode active material when the coating paper attached to the collector passes through the first section. A method for manufacturing the electrode is also provided.

Abstract: The present invention relates to a secondary battery. The secondary battery includes a can configured to accommodate an electrode assembly and a cap assembly bonded to an opening of the can. The cap assembly includes an upper cap provided in the opening and connected to an electrode tab of the electrode assembly and a lower cap configured to bond the upper cap to the opening. The lower cap includes a first bonding part bonded to a bottom surface of the upper cap to support the upper cap and a second bonding part formed on an outer circumferential surface of the first bonding part to fix the upper cap while being bonded to the upper cap.

Abstract: The present invention relates to a system for manufacturing an electrode for a secondary battery. The system for manufacturing the electrode for the secondary battery comprises a supply roller supplying a collector having a long sheet shape; an electrode active material coating device applying an electrode active material to a surface of the collector supplied by the supply roller to manufacture an unfinished electrode; a rolling roller rolling a surface of the unfinished electrode and adjusting a thickness of the electrode active material to manufacture a finished electrode; and an electrode quality inspection device inspecting quality of the electrode through a surface roughness value of the rolling roller and a surface roughness value of the electrode.

Abstract: Apparatus and methods of evaluating brittleness by measuring force applied to an electrode specimen by simulating a wound state of a jelly-roll type electrode assembly are disclosed herein. In an embodiment, a brittleness evaluation apparatus includes a jig unit, a driving unit, and a measurement analyzing unit. The jig unit includes two jigs, a groove formed between the jigs, a pressing plate, and guides. The jigs facing each other and have top surfaces formed in a horizontal plane and configured to receive a specimen arranged on the top surfaces along a length direction extending between and along the top surfaces. The pressing plate is arranged perpendicular to the length direction and configured to cause the specimen to bend by descending into the groove. The guides are located on each of the top surfaces of the jigs and configured to prevent distortion of the specimen during descent of the pressing plate.

Abstract: The present invention relates to a secondary battery. The secondary battery comprises an electrode assembly in which an electrode and a separator are alternately stacked and wound, wherein the electrode comprises a collector, a first coating layer in which an electrode active material is applied to a surface of the collector, and a second coating layer in which the electrode active material is applied to the outside of the first coating layer, wherein an end of the second coating layer has a length less than an end of first coating layer in a winding direction of the electrode, and a stepped portion occurs between the end of the first coating layer and the end of the second coating layer in a direction outward from a winding center.

Abstract: A jig assembly for measuring the tensile strength of an electrode at a bend having a similar radius to a core, an apparatus for measuring bending tensile strength including the jig assembly, and a method for measuring bending tensile strength that measures the tensile strength of an electrode at a bend having a similar radius to a core using the apparatus for measuring bending tensile strength are provided. The jig assembly of the present disclosure includes a fixing unit configured to fix a first end part of a sample, and a plate shaped bending jig configured to provide a one point bend to a lengthwise direction cross section of the sample and to guide a second end part of the sample toward a tensile testing load unit. According to the present disclosure, it is possible to measure the tensile strength of the electrode under a similar condition to a winding process before the electrode is used in real winding applications.

Abstract: The present disclosure relates to a secondary battery electrode, a manufacturing method for the same, and an electrode assembly, and more particularly, to a secondary battery electrode, a manufacturing method for the same, and an electrode assembly having improved stability. In accordance with an exemplary embodiment, a secondary battery electrode includes a current collector that extends in one direction, a first active material layer provided on one surface of the current collector and including a first inclined portion and a first protruding portion, and a second active material layer provided on the other surface of the current collector and including a second inclined portion and a second protruding portion. In particular, a position of the second protruding portion is controlled on the second active material layer to be disposed at a position that is not directly opposite to the first inclined portion with respect to the current collector.

Abstract: Apparatus and methods of evaluating brittleness by measuring force applied to an electrode specimen by simulating a wound state of a jelly-roll type electrode assembly are disclosed herein. In an embodiment, a brittleness evaluation apparatus includes a jig unit, a driving unit, and a measurement analyzing unit. The jig unit includes two jigs, a groove formed between the jigs, a pressing plate, and guides. The jigs facing each other and have top surfaces formed in a horizontal plane and configured to receive a specimen arranged on the top surfaces along a length direction extending between and along the top surfaces. The pressing plate is arranged perpendicular to the length direction and configured to cause the specimen to bend by descending into the groove. The guides are located on each of the top surfaces of the jigs and configured to prevent distortion of the specimen during descent of the pressing plate.

Abstract: The present invention relates to a secondary battery. The secondary battery comprises an electrode assembly in which an electrode and a separator are alternately stacked and wound, wherein the electrode comprises a collector, a first coating layer in which an electrode active material is applied to a surface of the collector, and a second coating layer in which the electrode active material is applied to the outside of the first coating layer, wherein an end of the second coating layer has a length less than an end of first coating layer in a winding direction of the electrode, and a stepped portion occurs between the end of the first coating layer and the end of the second coating layer in a direction outward from a winding center.

Abstract: A system for manufacturing an electrode for a secondary battery is disclosed herein. In an embodiment, the system for manufacturing the electrode for the secondary battery comprises a supply roller for supplying a collector having a long sheet shape; an electrode active material coating device for applying an electrode active material to a surface of the collector supplied by the supply roller to manufacture an unfinished electrode; a rolling roller for rolling a surface of the unfinished electrode and adjusting a thickness of the electrode active material to manufacture a finished electrode; and an electrode quality inspection device for inspecting quality of the electrode through a surface roughness value of the rolling roller, a surface roughness value of the surface of the electrode, and a rolling load value of the rolling roller.

Abstract: A jig assembly for measuring the tensile strength of an electrode at a bend having a similar radius to a core, an apparatus for measuring bending tensile strength including the jig assembly, and a method for measuring bending tensile strength that measures the tensile strength of an electrode at a bend having a similar radius to a core using the apparatus for measuring bending tensile strength are provided. The jig assembly of the present disclosure includes a fixing unit configured to fix a first end part of a sample, and a plate shaped bending jig configured to provide a one point bend to a lengthwise direction cross section of the sample and to guide a second end part of the sample toward a tensile testing load unit. According to the present disclosure, it is possible to measure the tensile strength of the electrode under a similar condition to a winding process before the electrode is used in real winding applications.

Abstract: The present invention relates to a system for manufacturing an electrode for a secondary battery. The system for manufacturing the electrode for the secondary battery comprises a supply roller supplying a collector having a long sheet shape; an electrode active material coating device applying an electrode active material to a surface of the collector supplied by the supply roller to manufacture an unfinished electrode; a rolling roller rolling a surface of the unfinished electrode and adjusting a thickness of the electrode active material to manufacture a finished electrode; and an electrode quality inspection device inspecting quality of the electrode through a surface roughness value of the rolling roller and a surface roughness value of the electrode.

Abstract: A cylindrical lithium secondary battery according to the present invention can reduce gas explosion by preventing gas concentration from being concentrated only on the upper top cap vent by increasing the gas spouting passage through which the inner gas of the can is spouted by forming a rupture portion of a material different from that of the can member on a part of the cylindrical can member, and when the inside or outside of the battery is exposed to a high temperature, by making, a shape-based alloy member, which causes cracking of the can member by deformation, included a part of the can member, the gas is discharged through the can vent by the cracking of the can member to prevent explosion before the tap cap safety vent operates by the internal air pressure, and ignition that may be caused by heating by internal or external heat may be prevented.