A rechargeable battery according to one embodiment of the present invention includes: an electrode assembly having a separator interposed between a first electrode and a second electrode; a case including an upper case having an open lower portion and a penetration hole in the upper portion thereof, and a lower case having an open upper portion to seal the lower portion of the upper case, and accommodating the electrode assembly therein; and a cap plate coupled to the upper case so as to seal the penetration hole and electrically insulated from the upper case, wherein the upper case and the lower case are coupled such that partial regions overlap, and an upper end of the lower case protrudes inwardly and is latched and fixed to the outside of the upper case.

The present disclosure discloses a battery core, a battery, and a battery pack. The battery core includes: at least one core, where each core has a plurality of tabs, the plurality of tabs successively form, after being converged, a tab end-portion staggered layer region, a tab soldering region, and a pre-soldered press-fit region, parts of the plurality of tabs exposed out of the core form a tab exposure region, and a length of the tab exposed out of the core in the tab exposure region is determined according to a width of the tab end-portion staggered layer region, a width of the tab soldering region, a width of the pre-soldered press-fit region, a thickness of the core, and a tab bending angle of the tab.

The present disclosure discloses a battery core, a battery, and a battery pack. The battery core includes: at least one core, where each core has a plurality of tabs, the plurality of tabs successively form, after being converged, a tab end-portion staggered layer region, a tab soldering region, and a pre-soldered press-fit region, parts of the plurality of tabs exposed out of the core form a tab exposure region, and a length of the tab exposed out of the core in the tab exposure region is determined according to a width of the tab end-portion staggered layer region, a width of the tab soldering region, a width of the pre-soldered press-fit region, a thickness of the core, and a tab bending angle of the tab.

The present invention relates to a secondary battery. The secondary battery includes an electrode assembly in which electrodes and separators are alternately stacked to be wound, a cylindrical can comprising an accommodation part, in which the electrode assembly is accommodated, the can having an opening, and a cap assembly configured to cover the opening. The cap assembly includes a safety vent comprising a notching part that is ruptured when an internal pressure of the battery increases, the notching part has a circular shape in a plan view, the electrode assembly comprises an electrode tab connected to each of the electrodes, the safety vent is connected to the electrode tab and an external terminal, wherein the electrode tab and the external terminal are connected to different sides of an inner side and an outer side with respect to the notching part in the safety vent in the plane view.

The present invention relates to a secondary battery. The secondary battery includes an electrode assembly in which electrodes and separators are alternately stacked to be wound, a cylindrical can comprising an accommodation part, in which the electrode assembly is accommodated, the can having an opening, and a cap assembly configured to cover the opening. The cap assembly includes a safety vent comprising a notching part that is ruptured when an internal pressure of the battery increases, the notching part has a circular shape in a plan view, the electrode assembly comprises an electrode tab connected to each of the electrodes, the safety vent is connected to the electrode tab and an external terminal, wherein the electrode tab and the external terminal are connected to different sides of an inner side and an outer side with respect to the notching part in the safety vent in the plane view.

A technical object to be solved according to the present disclosure is to provide a secondary battery which has reduced electrical resistance by directly connecting an electrode assembly to a can and/or a terminal without lead tabs and also has an increased battery capacity by removing lead tabs. To this end, the present disclosure provides a secondary battery comprising: a can; an electrode assembly accommodated in the can and including a first uncoated portion extending in a first direction and a second uncoated portion extending in a second direction opposite to the first direction; a first current collector plate electrically connected to the first uncoated portion of the electrode assembly; a first terminal portion coupled to the can and electrically connected to the first current collector plate; and a second terminal portion coupled to the can and electrically connected to the second uncoated portion of the electrode assembly.

Provided is a technique to reduce voids between an electrode tab and a current collecting unit in a portion where the electrode tab and the current collecting unit are welded. The secondary battery manufacturing method disclosed herein is a method of manufacturing a secondary battery including an electrode body having an electrode tab and a current collecting unit electrically connected to the electrode body. This method includes: welding between the electrode tab and the current collecting unit, by sandwiching the electrode tab between a transparent material and the current collecting unit and then applying laser to penetrate the transparent material.

A lithium ion cell includes a ribbon-shaped electrode-separator assembly having an anode, a separator, and a cathode. The electrode-separator assembly has two terminal end faces or two terminal sides. The anode comprises a ribbon-shaped anode current collector having a first longitudinal edge, the cathode comprises a ribbon-shaped cathode current collector having a first longitudinal edge, and the electrode-separator assembly is enclosed in a housing. The first longitudinal edge of the anode current collector protrudes from one of the terminal end faces or terminal sides of the stack and the first longitudinal edge of the cathode current collector protrudes from the other. A contact sheet metal member is in direct contact with a respective longitudinal edge. A part of the housing serves as the contact sheet metal member and/or the contact sheet metal member forms a part of the housing enclosing the electrode-separator assembly.

A lithium ion cell includes a ribbon-shaped electrode-separator assembly having an anode, a separator, and a cathode. The electrode-separator assembly has two terminal end faces or two terminal sides. The anode comprises a ribbon-shaped anode current collector having a first longitudinal edge, the cathode comprises a ribbon-shaped cathode current collector having a first longitudinal edge, and the electrode-separator assembly is enclosed in a housing. The first longitudinal edge of the anode current collector protrudes from one of the terminal end faces or terminal sides of the stack and the first longitudinal edge of the cathode current collector protrudes from the other. A contact sheet metal member is in direct contact with a respective longitudinal edge. A part of the housing serves as the contact sheet metal member and/or the contact sheet metal member forms a part of the housing enclosing the electrode-separator assembly.

A lithium-ion cell includes a ribbon-shaped electrode-separator assembly having an anode, a cathode, and a separator. The electrode-separator assembly is in the form of a winding with two terminal end faces. The anode has a ribbon-shaped anode current collector with a free edge strip extending along a first longitudinal edge that is not loaded with negative electrode material. The cathode has a ribbon-shaped cathode current collector with a free edge strip extending along a first longitudinal edge that is not loaded with positive electrode material. The separator has at least one inorganic material that improves its resistance to thermal stress. The lithium-ion cell further includes a housing enclosing the electrode-separator assembly and a metallic contact element. The metallic contact element is connected to a respective first longitudinal edge of one of the current collectors by a weld.