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EP-4738558-A1 - SECONDARY BATTERY

EP4738558A1EP 4738558 A1EP4738558 A1EP 4738558A1EP-4738558-A1

Abstract

Provided is a secondary battery. According to one aspect of the present disclosure, the secondary battery comprises an electrode assembly accommodated inside a can, a current collector electrically connected to an electrode tab of the electrode assembly, and a rivet fastened to the current collector and functioning as an electrode terminal, wherein the current collector comprises a first coupling sleeve, the rivet comprises a second coupling sleeve fastened to the first coupling sleeve, and the first coupling sleeve is provided to be inserted into and fastened to the second coupling sleeve in a direction corresponding to a central axis of the electrode assembly.

Inventors

  • KWAK, SEUNG HO
  • PARK, SOO MIN
  • PARK, JAE YUN
  • LEE, JOO HYUK
  • CHO, Myeong Shin
  • PARK, JUNG NAM

Assignees

  • SK On Co., Ltd.

Dates

Publication Date
20260506
Application Date
20251028

Claims (15)

  1. A secondary battery comprising: an electrode assembly 120 accommodated inside a can; a current collector 130 electrically connected to an electrode tab of the electrode assembly 120; and a rivet 140 fastened to the current collector 130 and functioning as an electrode terminal, wherein the current collector 130 comprises a first coupling sleeve 131, 231, 331, the rivet 140 comprises a second coupling sleeve 141, 241, 341 fastened to the first coupling sleeve 131, 231, 331, and the first coupling sleeve 131, 231, 331 is provided to be inserted into and fastened to the second coupling sleeve 141, 241, 341 in a direction corresponding to a central axis of the electrode assembly 120.
  2. The secondary battery of claim 1, wherein the first coupling sleeve 131, 231, 331 is inserted into an inner space of the second coupling sleeve 141, 241, 341 and fastened, and the second coupling sleeve 141, 241, 341 comprises an inner surface fastened in close contact with an outer surface of the first coupling sleeve 131, 231, 331.
  3. The secondary battery according to any one of the preceding claims, wherein the first coupling sleeve 131, 231, 331 interlocks with the second coupling sleeve 141, 241, 341 to restrict separation in a direction of the central axis.
  4. The secondary battery according to any one of the preceding claims, wherein the first coupling sleeve 131, 231, 331 comprises a first fixing protrusion, the second coupling sleeve 141, 241, 341 comprises a fixing groove fastened to the first fixing protrusion, and the fixing groove is provided to restrict separation of the first fixing protrusion in a direction of the central axis.
  5. The secondary battery according to any one of the preceding claims, wherein the first coupling sleeve 131, 231, 331 is formed of an elastic material having electrical conductivity and is provided to be elastically in close contact with the second coupling sleeve 141, 241, 341.
  6. The secondary battery according to any one of the preceding claims, wherein the first coupling sleeve 131, 231, 331 is provided to be at least partially bonded to the second coupling sleeve 141, 241, 341 by an electrically conductive adhesive.
  7. The secondary battery according to any one of the preceding claims, wherein the second coupling sleeve 141, 241, 341 comprises a first chamfer at one end portion through which the first coupling sleeve 131, 231, 331 enters an inner space.
  8. The secondary battery according to any one of the preceding claims, further comprising a gasket 150 fastened between the can and the rivet 140.
  9. The secondary battery according to any one of the preceding claims, wherein the gasket 150 comprises: a first gasket 151 disposed on an inside of the can; and a second gasket 152 disposed on an outside of the can and fastened to the first gasket.
  10. The secondary battery according to any one of the preceding claims, wherein the first gasket 151 is provided with a first gasket coupling portion 151a extending in a direction toward the inside and outside of the can, and the second gasket 152 is provided with a second gasket coupling portion 152a having a shape corresponding to the first gasket coupling portion 151a and fastened to the first gasket coupling portion 151a.
  11. The secondary battery according to any one of the preceding claims, wherein the gasket 151 is provided with an upper surface portion in close contact with the rivet 140 on an outside of the can, and the first coupling sleeve 131, 231, 331 is fastened to the second coupling sleeve 141, 241, 341 at a predetermined distance above the upper surface portion.
  12. The secondary battery according to any one of the preceding claims, wherein the rivet 140 comprises a separation preventing protrusion that radially restrains and supports the first coupling sleeve 131, 231, 331 between the rivet and the second coupling sleeve 141, 241, 341.
  13. The secondary battery according to any one of the preceding claims, wherein the separation preventing protrusion is formed to be spaced a predetermined interval apart from an inner surface of the second coupling sleeve 141, 241, 341, and an outer surface is in close contact with an inner surface of the first coupling sleeve 131, 231, 331 to restrain and support the first coupling sleeve 131, 231, 331 in a region comprising an upper end portion of the first coupling sleeve 131, 231, 331.
  14. The secondary battery according to any one of the preceding claims, wherein the separation preventing protrusion is provided with a second chamfer at one end portion through which the first coupling sleeve 131, 231, 331 enters between the separation preventing protrusion and the second coupling sleeve 141, 241, 341.
  15. The secondary battery according to any one of the preceding claims, wherein the separation preventing protrusion extends in a direction corresponding to the central axis and is provided such that one end portion supports a bottom surface of the current collector 130, wherein the separation preventing protrusion comprises a second fixing protrusion fastened to the bottom surface of the current collector 130, and the second fixing protrusion comprises a third chamfer configured to guide insertion of the first coupling sleeve 131, 231, 331.

Description

TECHNICAL FIELD Embodiments of the present disclosure relate a secondary battery. BACKGROUND A secondary battery is one of the energy storage means which can be charged and discharged through electrochemical reactions. The secondary battery is used in various fields using electrical energy. For example, the secondary battery is widely used in the field of mobile devices such as mobile phones, notebooks, and tablets, and broader use is being explored in the field of transportation means such as vehicles, aircraft, and ships. In addition, demand for secondary batteries is increasing in the field of energy storage systems (ESSs) for utilizing surplus power. Secondary batteries can be classified into pouch-types, prismatic-types, cylindrical-types, coin-types, and the like depending on their packaging form. Among them, cylindrical secondary batteries have the advantages of standardized sizes and ease of mass production, and thus recently, demand therefor in the field of vehicles and the like has been rapidly increasing. Cylindrical secondary batteries may have a structure in which a jelly-roll type electrode assembly is accommodated in a can along with an electrolyte. In addition, the electrode assembly may be provided in a form in which a positive electrode and a negative electrode, disposed with a separator interposed therebetween, are wound in a roll shape. SUMMARY Some embodiments of the present disclosure are directed to providing a secondary battery. Some embodiments of the present disclosure are also directed to providing an appropriate coupling structure of a current collector and a rivet in a cylindrical secondary battery. Some embodiments of the present disclosure are also directed to improving the assembly convenience of a current collector and a rivet. Some embodiments of the present disclosure are also directed to implementing an appropriate electrical connection between a current collector and a rivet. Some embodiments of the present disclosure may be widely applied in the field of green technology such as an electric vehicle, a battery charging station, solar power generation, and wind power generation utilizing batteries. In addition, some embodiments of the present disclosure may be used in an eco-friendly electric vehicle (EV), a hybrid vehicle, and the like to prevent climate change by suppressing air pollution and greenhouse gas emissions. According to an aspect of the present disclosure, there is provided a secondary battery comprising an electrode assembly accommodated inside a can, a current collector electrically connected to an electrode tab of the electrode assembly, and a rivet fastened to the current collector and functioning as an electrode terminal, wherein the current collector comprises a first coupling sleeve, the rivet comprises a second coupling sleeve fastened to the first coupling sleeve, and the first coupling sleeve is provided to be inserted into and fastened to the second coupling sleeve in a direction corresponding to a central axis of the electrode assembly. In some embodiments, the first coupling sleeve may be inserted into an inner space of the second coupling sleeve and fastened, and the second coupling sleeve may comprise an inner surface fastened in close contact with an outer surface of the first coupling sleeve. In some embodiments, the first coupling sleeve may interlock with the second coupling sleeve to restrict separation in a direction of the central axis. In some embodiments, the first coupling sleeve may comprise a first fixing protrusion, the second coupling sleeve may comprise a fixing groove fastened to the first fixing protrusion, and the fixing groove may be provided to restrict separation of the first fixing protrusion in a direction of the central axis. In some embodiments, the first coupling sleeve may be formed of an elastic material having electrical conductivity and provided to be elastically in close contact with the second coupling sleeve. In some embodiments, the first coupling sleeve may be provided to be at least partially bonded to the second coupling sleeve by an electrically conductive adhesive. In some embodiments, the second coupling sleeve may comprise a first chamfer at one end portion through which the first coupling sleeve enters an inner space. In some embodiments, the secondary battery may further comprise a gasket fastened between the can and the rivet. In some embodiments, the gasket may comprise a first gasket disposed on the inside of the can and a second gasket disposed on the outside of the can and fastened to the first gasket. In some embodiments, the first gasket may be provided with a first gasket coupling portion extending in a direction toward the inside and outside of the can, and the second gasket may be provided with a second gasket coupling portion having a shape corresponding to the first gasket coupling portion and fastened to the first gasket coupling portion. In some embodiments, the gasket may be provided wit