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EP-4456274-B1 - CYLINDRICAL BATTERY, ELECTRIC APPARATUS AND MANUFACTURING METHOD FOR CYLINDRICAL BATTERY

EP4456274B1EP 4456274 B1EP4456274 B1EP 4456274B1EP-4456274-B1

Inventors

  • YU, Hongjiang
  • LUO, Zhigao
  • CHEN, Jicheng

Dates

Publication Date
20260506
Application Date
20240423

Claims (12)

  1. A cylindrical battery, comprising: a housing (1), the housing (1) is provided with an opening (14) and an accommodating cavity (11) for accommodating a cell (3); a first current collector (2), the first current collector (2) is arranged in the accommodating cavity (11), and the first current collector (2) comprises a first main body portion (21) and a second main body portion (22), the first main body portion (21) is connected to the cell (3), and the second main body portion (22) is connected to the housing (1); a side wall of the housing (1) is provided with a beading portion (12), the beading portion (12) is recessed towards the accommodating cavity (11) to form a first groove (16) on an outer wall of the housing (1), and correspondingly form a protrusion (13) on an inner wall of the housing (1), at least a part of the second main body portion (22) extends from an edge of the first main body portion (21) to the protrusion (13) and covers the protrusion (13) wherein the second main body portion (22) comprises a welding segment (24) and a limiting segment (25), the limiting segment (25) is connected to the welding segment (24) and the first main body portion (21), and the second main body portion (22) is connected to the protrusion (13) by the welding segment (24);. wherein, before the beading portion (12) is recessed, the second main body portion (22) comprises the welding segment (24) and a buffer segment (23) located between the welding segment (24) and the first main body portion (21), and the buffer segment (23) is configured for being bent and deformed to form the limiting segment (25), characterized in that a cross section shape of the buffer segment (23) is zigzag.
  2. The cylindrical battery as claimed in claim 1, wherein the welding segment (24) is located on a side of the protrusion (13) that is oriented towards the opening (14).
  3. The cylindrical battery as claimed in claim 1, wherein the welding segment (24) and the limiting segment (25) abut against the protrusion (13).
  4. The cylindrical battery as claimed in claim 1, wherein a cross section shape of the limiting segment (25) is consistent with a cross section shape of the protrusion (13).
  5. The cylindrical battery as claimed in claim 4, wherein cross section shapes of the limiting segment (25) and the protrusion (13) are both V-shaped.
  6. The cylindrical battery as claimed in claim 1, wherein before the beading portion (12) is recessed, an extension direction of the second main body portion (22) is perpendicular to that of the first main body portion (21).
  7. The cylindrical battery as claimed in claim 1, wherein the first main body portion (21) and the second main body portions (22) are integrally formed.
  8. An electric apparatus, comprising the cylindrical battery as claimed in any one of claims 1 to 7.
  9. A method for manufacturing the cylindrical battery as claimed in claim 1, comprising the following steps: S1: winding to form a cylindrical cell (3), the cylindrical cell (3) has a positive electrode tab and a negative electrode tab; S2: flattening the positive electrode tab and the negative electrode tab of the cylindrical cell (3); S3: welding the positive electrode tab to a second current collector (4), and welding the negative electrode tab to a first current collector (2), so as to obtain a cell assembly; S4: placing the cell assembly into a housing (1); S5: performing ultrasonic torque welding on the second current collector (4) and a positive electrode terminal (61); S6: performing beading on the housing (1), such that a beading portion (12) of the housing (1) is recessed inwards, an outer wall of the housing (1) is recessed to form a first groove (16), and an inner wall of the housing (1) is protruded to form a protrusion (13), a top of the protrusion (13) pushes the buffer segment (23) such that the buffer segment (23) is bent inwards and deformed to form a limiting segment (25); S7: welding the welding segment (24) to the protrusion (13) on a surface of the protrusion (13) away from the cell assembly; and S8: mounting a top cover assembly (5), and mounting the top cover assembly (5) to an opening (14) of the housing (1) in a clamping manner.
  10. The method for manufacturing the cylindrical battery as claimed in claim 9, wherein before the step S1, the manufacturing method further comprises steps of: die-cutting a positive electrode plate to form a plurality of positive electrode tabs, and die-cutting a negative electrode plate to form a plurality of negative electrode tabs.
  11. The method for manufacturing the cylindrical battery as claimed in claim 9, wherein in the step S6, the limiting segment (25) forms a second groove, and the protrusion (13) abuts against the second groove to fix the protrusion (13) and the limiting segment (25).
  12. The method for manufacturing the cylindrical battery as claimed in claim 9, wherein in the step S6, the protrusion (13) and the limiting segment (25) both form V-shaped cross sections.

Description

Cross-Reference to Related Application The present invention claims priority to and the benefit of Chinese Patent Application No. 202320922089.1, filed with the China National Intellectual Property Administration (CHIPA) on April 23 2023. Technical Field The present invention relates to the technical field of batteries, and in particular, to a cylindrical battery, an electric apparatus and a manufacturing method for a cylindrical battery. Background In the related art, a welding position and a beading portion need to be reserved in a cylindrical battery, which causes the height of a battery housing to be increased, which means that when a battery is assembled into a battery module, more internal spaces need to be reserved for the battery module, and the energy density is significantly reduced. KR20220155017A relates to a secondary battery, providing a secondary battery capable of reducing heat generation and improving safety by reducing a welding area. To this end, the present invention provides a secondary battery including: an electrode assembly having a first lug and a second lug disposed on an opposite side of the first lug; a first current collector soldered on the first wiring sheet of the electrode assembly and having a diameter greater than that of the electrode assembly; and a housing assembly including a housing accommodating the electrode assembly and the first current collector, a second current collector in close contact with the second lug of the electrode assembly, and a terminal unit electrically connected to the second current collector and penetrating the housing. WO2024133407A1, which belongs to the state of the Art under Article 54(3) EPC, discloses a cylindrical secondary cell and methods for manufacturing the cylindrical secondary- cell. The cylindrical secondary cell includes a cylindrical can having a beading groove formed in a wall of the cylindrical can and arranged around the circumference of the cylindrical can, and a first conductive sheet, with first electrode coating, wound to form a jelly roll which is arranged in the cylindrical can, and wherein the first conductive sheet includes a portion free of first electrode coating which protrudes on a first end side of the jelly roll. The cylindrical secondary cell further includes a current collector disc which is electrically conductive and arranged at the first end side of the jelly roll and in direct contact with at least part of the portion free of first electrode coating of the first conductive sheet, wherein the current collector disc abuts the apex of the beading groove. Summary The scope of the present invention is defined by the attached claims. A technical problem to be solved by the present invention is to provide a cylindrical battery with a relatively low height, so as to reduce a space occupied by the cylindrical battery when the cylindrical battery is mounted into a battery module. In order to solve the described technical problem, the present invention adopt the following technical solutions: The present invention provides a cylindrical battery, including: a housing, the housing is provided with an opening and an accommodating cavity for accommodating a cell; a first current collector, the first current collector is arranged in the accommodating cavity, and the first current collector includes a first main body portion and a second main body portion, the first main body portion is connected to the cell, and the second main body portion is connected to the housing; a side wall of the housing is provided with a beading portion, the beading portion is recessed towards the accommodating cavity to form a first groove on an outer wall of the housing, and correspondingly form a protrusion on an inner wall of the housing, at least a part of the second main body portion extends from an edge of the first main body portion to the protrusion and covers the protrusion. According to the invention, the second main body portion includes a welding segment and a limiting segment, the limiting segment is connected to the welding segment and the first main body portion, and the second main body portion is connected to the protrusion by the welding segment. Specifically, before the beading portion is recessed towards the accommodating cavity, the second main body portion includes a welding segment and a buffer segment located between the welding segment and the first main body portion, the beading portion is arranged corresponding to the buffer segment, and the buffer segment has a cross-section shape that is zigzag and is able to be bent and deformed as the beading portion is recessed inwards; when the beading portion is recessed towards the accommodating cavity so that an inner side wall of the housing forms the protrusion correspondingly, the protrusion pushes the buffer segment such that the buffer segment is bent inwards and deformed to form the limiting segment. The protrusion and the limiting segment are integrally formed by a bea