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CN-121986409-A - Battery monomer, battery and power consumption device

CN121986409ACN 121986409 ACN121986409 ACN 121986409ACN-121986409-A

Abstract

A battery cell (61) comprises an electrode assembly (10), a shell (20) provided with a containing cavity and an opening end (20 b) communicated with the containing cavity, an end cover (30) covered on the opening end (20 b), a current collecting assembly (40) electrically connected with the electrode assembly (10) and the shell (20), wherein the containing cavity comprises a pressure release cavity (pr) and an electric cavity (e 1), the pressure release cavity (pr) is positioned between the current collecting assembly (40) and the end cover (30), the electric cavity (e 1) is configured to contain the electrode assembly (10), the end cover (30) is provided with a pressure release part (50), at least part of the pressure release part (50) is arranged on a cavity wall of the pressure release cavity (pr), and the current collecting assembly (40) is provided with at least one channel communicated with the electric cavity (e 1) and the pressure release cavity (pr).

Inventors

  • LI ZHEN
  • BAI XIANGYUN
  • WEN YUQIAN
  • DAI XUEXIAN

Assignees

  • 宁德时代新能源科技股份有限公司

Dates

Publication Date
20260505
Application Date
20240514

Claims (20)

  1. A battery cell (61), comprising: An electrode assembly (10); A housing (20) having a receiving cavity and an open end (20 b) in communication with the receiving cavity; an end cap (30) which is covered on the open end (20 b); -a current collecting assembly (40) electrically connected to the electrode assembly (10) and the housing (20), the containment cavity comprising a pressure relief cavity (pr) and an electrical cavity (el), the pressure relief cavity (pr) being located between the current collecting assembly (40) and the end cap (30), the electrical cavity (el) being configured to contain the electrode assembly (10); The end cover (30) is provided with a pressure relief part (50), at least part of the pressure relief part (50) is arranged on the cavity wall of the pressure relief cavity (pr), and the current collecting assembly (40) is provided with at least one channel which is communicated with the electric cavity (el) and the pressure relief cavity (pr).
  2. The battery cell (61) of claim 1 wherein the at least one channel comprises a first channel (4A) located at a perimeter of the pressure relief cavity (pr).
  3. The battery cell (61) of claim 1 or2 wherein the at least one channel comprises a plurality of the first channels (4A), the plurality of first channels (4A) being spaced along the perimeter of the pressure relief chamber (pr).
  4. A battery cell (61) as claimed in claim 3 wherein a plurality of the first channels (4A) are equally spaced along the perimeter of the pressure relief chamber (pr).
  5. The battery cell (61) of any of claims 2-4 wherein the end cap (30) is electrically connected to the housing (20), the current collecting assembly (40) comprising: A first conductive member (41) welded to the end cap (30) and having a hollow portion (41 a) penetrating in the thickness direction of the end cap (30), and A second conductive member (42) electrically connected to the first conductive member (41) and welded to a first tab (12) of the electrode assembly (10) on a side adjacent to the end cap (30); The end cover (30), the hollow part (41 a) and the second conductive part (42) enclose the pressure release cavity (pr), and the first channel (4A) is arranged between the first conductive part (41) and the second conductive part (42) and is communicated with the hollow part (41 a).
  6. The battery cell (61) of claim 5 wherein the end cap (30) is of a different base material than the first tab (12); wherein the first conductive member (41) and the end cover (30) are made of the same base material, and/or the second conductive member (42) and the first tab (12) are made of the same base material.
  7. The battery cell (61) of claim 6, wherein the end cap (30) and the first conductive member (41) are both steel and the first tab (12) and the second conductive member (42) are both copper.
  8. The battery cell (61) according to any one of claims 5-7, wherein the electrode assembly (10) is a cylindrical electrode assembly, the second conductive member (42) comprises a plate body (42 a), an edge region of the plate body (42 a) is welded with the first conductive member (41), and a notch (42 b) is formed, and the notch (42 b) is at least partially exposed from the hollow portion (41 a) as the first channel (4A).
  9. The battery cell (61) of claim 8, wherein the edge region of the plate body (42 a) is provided with a plurality of notches (42 b), and the plurality of notches (42 b) are arranged at intervals along the circumferential direction of the plate body (42 a).
  10. The battery cell (61) of claim 9, wherein the plurality of notches (42 b) are equally spaced along the circumferential direction of the plate body (42 a).
  11. The battery cell (61) of any one of claims 8-10, wherein the at least one channel further comprises a second channel (4B) open at the center of the plate body (42 a), a portion of the plate body (42 a) between the second channel (4B) and the edge region being welded to the first tab (12).
  12. The battery cell (61) as claimed in claims 5-7, wherein the electrode assembly (10) is a cylindrical electrode assembly, the second conductive member (42) includes a flat plate portion (42 d) and a convex portion (42 e), the convex portion (42 e) protrudes from the flat plate portion (42 d) in a direction away from the electrode assembly (10), a concave portion (42 g) is formed on an inner side, an orthographic projection of the concave portion (42 g) on the first conductive member (41) at least partially coincides with the hollow portion (41 a), the convex portion (42 e) is welded with the first conductive member (41), and the first channel (4A) is provided to the convex portion (42 e).
  13. The battery cell (61) according to claim 12, wherein the protruding portion (42 e) is formed with a first groove (42 h) recessed from the flat plate portion (42 d) in a direction away from the electrode assembly (10) on a side adjacent to the electrode assembly (10), an inner side wall of the protruding portion (42 e) is located between the first groove (42 h) and the recessed portion (42 g), and a third through hole (42 i) is opened, the first groove (42 h) and the third through hole (42 i) being at least a part of the first passage (4A).
  14. The battery cell (61) as claimed in claim 13, wherein the convex portion (42 e) is provided with a plurality of the third through holes (42 i) between the first groove (42 h) and the concave portion (42 g), the plurality of the third through holes (42 i) being arranged at intervals along the circumferential direction of the second conductive member (42).
  15. The battery cell (61) of claim 14, wherein the plurality of third through holes (42 i) are equally spaced along the circumferential direction of the second conductive member (42).
  16. The battery cell (61) of any one of claims 13-15 wherein the outer side of the protrusion (42 e) further extends outwardly by a ledge (42 j).
  17. The battery cell (61) of claim 16, wherein an end surface of the protruding edge (42 j) adjacent to the electrode assembly (10) side is flush with an end surface of the flat plate portion (42 d) adjacent to the electrode assembly (10) side.
  18. The battery cell (61) as claimed in claim 16 or 17, wherein the first conductive member (41) is in a circular ring shape, an outer ring radius (D1) of the first conductive member (41) is larger than a maximum distance (D2) from an outer side wall of the protruding portion (42 e) to a center of the recessed portion (42 g), the first conductive member (41), the protruding edge (42 j), and the protruding portion (42 e) together enclose a second groove (42 k) located outside the protruding portion (42 e), an outer side wall of the protruding portion (42 e) is provided between the second groove (42 k) and the first groove (42 h), and a fourth through hole (42 l) is opened, the second groove (42 k), the first groove (42 h), the fourth through hole (42 l), and the third through hole (42 i) are at least a part of the first channel (4A).
  19. The battery cell (61) of claim 18 wherein an outer sidewall of the protruding portion (42 e) is provided with a plurality of the fourth through holes (42 l) between the second groove (42 k) and the first groove (42 h), and a plurality of the third through holes (42 i) between the first groove (42 h) and the recessed portion (42 g), the plurality of the third through holes (42 i) and the plurality of the fourth through holes (42 l) are each arranged at intervals in a circumferential direction of the second conductive member (42), and the plurality of the third through holes (42 i) and the plurality of the fourth through holes (42 l) are at least partially aligned or staggered in a radial direction.
  20. The battery cell (61) of any one of claims 13-19 wherein the protrusion (42 e) is annular and forms the first groove (42 h) in the shape of an annulus.

Description

Battery monomer, battery and power consumption device Technical Field The present invention relates to the field of battery technologies, and in particular, to a battery cell, a battery and an electric device. Background The secondary battery, especially the lithium ion battery, has the advantages of high voltage, large specific energy, long cycle life, no pollution, wide working temperature range, small self-discharge and the like, is widely applied to the power equipment of portable electronic equipment, energy storage devices and large new energy electric automobiles, and has great significance for solving the pollution of human environment and energy crisis. With the widespread use of lithium ion batteries, the reliability of the use of the batteries is a problem of close concern to manufacturers. Disclosure of Invention In one aspect of the disclosure, a battery cell is provided that includes an electrode assembly, a housing having a receiving cavity and an open end in communication with the receiving cavity, an end cap covering the open end, a current collecting assembly electrically connected to the electrode assembly and the housing, the receiving cavity including a pressure relief cavity between the current collecting assembly and the end cap and an electrical cavity configured to receive the electrode assembly, wherein the end cap has a pressure relief portion at least partially disposed on a cavity wall of the pressure relief cavity, the current collecting assembly having at least one channel communicating the electrical cavity with the pressure relief cavity. In this embodiment, the collector assembly is all electrically connected with electrode assembly and casing to realize the electricity between electrode assembly and the casing and be connected, and the pressure release chamber that forms between collector assembly and the end cover that has pressure release portion can realize its and the intercommunication that holds electrode assembly's electric cavity through the passageway on the collector assembly, thereby in the gas that produces when the electrode assembly takes place under the circumstances such as thermal runaway can enter into the pressure release chamber fast, trigger the pressure release portion of locating on the chamber wall of pressure release chamber at least partially and carry out the pressure release, and then reduce the inside pressure accumulation of battery monomer and excessively lead to the fact risk such as casing inflation deformation, rupture. In some embodiments, the at least one channel includes a first channel located at a perimeter of the pressure relief cavity. In this embodiment, through the first passageway that sets up along the periphery of pressure release chamber to communicate and hold chamber and pressure release chamber, substances such as the inside high pressure gas that produces of battery monomer can get into the pressure release chamber at the periphery of pressure release chamber through first passageway to the high pressure gas of the periphery of guide pressure release chamber gets into the pressure release intracavity fast, improves pressure release efficiency. In some embodiments, the at least one channel comprises a plurality of the first channels, the plurality of first channels being spaced along the perimeter of the pressure relief cavity. In this embodiment, through a plurality of first channels that follow the peripheral interval of pressure release chamber is arranged can all realize the pressure release route in a plurality of directions of the peripheral of pressure release chamber to improve the single pressure release efficiency of battery, help reducing the inside local high risk of pressure of single battery. In some embodiments, a plurality of the first channels are equally spaced along the perimeter of the pressure relief cavity. In this embodiment, the plurality of first channels are arranged at equal intervals along the periphery of the pressure relief cavity, so that the high-pressure gas can enter the pressure relief cavity from the periphery of the pressure relief cavity more uniformly to realize pressure relief. In some embodiments, the end cover is electrically connected with the shell, the current collecting assembly comprises a first conductive member welded with the end cover and provided with a hollow part penetrating through the end cover in the thickness direction, and a second conductive member electrically connected with the first conductive member and welded with a first tab of the electrode assembly on one side adjacent to the end cover, wherein the end cover, the hollow part and the second conductive member enclose the pressure release cavity, and the first channel is arranged between the first conductive member and the second conductive member and communicated with the hollow part. In this embodiment, the current collecting component that adopts first electrically conductive piece and second electrically c