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CN-122029690-A - Battery cell, battery and electricity utilization device

CN122029690ACN 122029690 ACN122029690 ACN 122029690ACN-122029690-A

Abstract

The embodiment of the application provides a battery cell, a battery and an electric device, wherein the battery cell comprises a shell (1), the shell comprises a first wall (12), the first wall (12) is provided with a pressure release part (2), an electrode assembly (3) is arranged in the shell (1), the electrode assembly (3) comprises an electrode main body (31) and a first tab (32), the first tab (32) is led out from one end of the electrode main body (31), and a first current collector (4) is configured to electrically connect the first tab (32) with the shell (1), the first current collector (4) is at least partially positioned between the first tab (32) and the pressure release part (2), at least one ventilation part (41) and at least one guide part (42) are arranged on the first current collector (4), the ventilation part (41) penetrates through the first current collector (4) along the thickness direction of the first wall (12), and the guide part (42) is arranged in the peripheral area of the ventilation part (41).

Inventors

  • WU GUANGJIN
  • XIE CHENGBIN
  • GUO ZHIJUN
  • MA RUOYAN
  • LIN JUNYI

Assignees

  • 宁德时代新能源科技股份有限公司

Dates

Publication Date
20260512
Application Date
20240514

Claims (20)

  1. A battery cell, comprising: A housing (1) comprising a first wall (12), said first wall (12) being provided with a pressure relief member (2); An electrode assembly (3) provided in the case (1), the electrode assembly (3) including an electrode main body (31) and a first tab (32), the first tab (32) being led out from one end of the electrode main body (31), and The first current collector (4) is configured to electrically connect the first tab (32) and the housing (1), the first current collector (4) is at least partially located between the first tab (32) and the pressure release component (2), at least one ventilation part (41) and at least one guide part (42) are arranged on the first current collector (4), the ventilation part (41) penetrates through the first current collector (4) along the thickness direction of the first wall (12), and the guide part (42) is arranged in the peripheral area of the ventilation part (41).
  2. The battery cell of claim 1, wherein the guide (42) includes at least one of a through hole (42A) or a score (42B).
  3. The battery cell according to claim 1 or2, wherein the guide portion (42) extends in a radial direction of the first current collector (4).
  4. A battery cell according to any one of claims 1-3, wherein the at least one guiding portion (42) comprises a first guiding portion (421), the first guiding portion (421) being in communication with the venting portion (41) near a first end of the venting portion (41).
  5. The battery cell according to claim 4, wherein two of the first guide portions (421) are located on the same straight line, and both of the first guide portions (421) communicate with the ventilation portion (41) near the first end of the ventilation portion (41).
  6. The battery cell according to any one of claims 1 to 5, wherein the at least one guiding portion (42) includes a second guiding portion (422), and a preset spacing portion (423) is provided between a first end of the second guiding portion (422) adjacent to the ventilation portion (41) and a side wall of the ventilation portion (41).
  7. The battery cell according to claim 6, wherein the two second guide portions (422) are positioned on the same straight line, and a preset spacer portion (423) is provided between the first ends of the two second guide portions (422) and the side wall of the ventilation portion (41).
  8. The battery cell according to claim 6 or 7, wherein the preset spacer (423) is configured to break if the air pressure within the housing (1) exceeds a preset threshold.
  9. The battery cell according to any one of claims 6 to 8, wherein the length (X) of the preset spacer (423) is less than 15mm, and the thickness of the preset spacer (423) is less than 2mm.
  10. The battery cell according to any one of claims 1 to 9, wherein a plurality of the guide portions (42) are arranged at intervals along the circumferential direction of the first current collector (4).
  11. The battery cell according to claim 10, wherein a plurality of the guide portions (42) are arranged in central symmetry with respect to the center of the first current collector (4).
  12. The battery cell according to claim 11, wherein a distance between second ends of the two guide portions (42) located on the same straight line and each away from the ventilation portion (41) is L, and a maximum radial dimension of the first current collector (4) is D, l=0.1d to 0.8d.
  13. The battery cell according to claim 12, wherein the first current collector (4) is provided with a thickness T in a region where the guide portion (42) is located, and the guide portion (42) has a width W, w=t to 5T.
  14. The battery cell according to any one of claims 1 to 13, wherein the first current collector (4) is provided with a positioning hole (424) at a second end remote from the ventilation portion (41).
  15. The battery cell according to claim 14, wherein the at least one guide portion (42) includes a plurality of guide portions (42) extending in a radial direction of the first current collector (4), two of the guide portions (42) of the plurality of guide portions (42) are positioned in a same straight line, the positioning holes (424) are provided in two, and the two positioning holes (424) are provided at respective second ends of the two guide portions (42) in the same straight line.
  16. The battery cell according to claim 15, wherein the positioning hole (424) is a circular hole, the thickness of the area where the guide portion (42) is disposed on the first current collector (4) is T, and the diameter of the circular hole is d, d=4t to 10T.
  17. The battery cell according to any one of claims 1 to 16, wherein the ventilation portion (41) is polygonal, and the guide portion (42) is aligned with a corner region of the ventilation portion (41) near a first end of the ventilation portion (41).
  18. The battery cell according to claim 17, wherein a plurality of the guide portions (42) are provided, and the number of the guide portions (42) is identical to the number of the corners of the polygon, and the plurality of the guide portions (42) are provided in one-to-one correspondence with the plurality of the corners of the polygon.
  19. The battery cell according to any one of claims 1 to 18, wherein the first current collector (4) includes a case connecting portion (44) and a tab connecting portion (43) that are different in base material, the case connecting portion (44) is the same as the base material of the first wall (12), the tab connecting portion (43) is the same as the base material of the first tab (32), and the ventilation portion (41) and the guide portion (42) are provided at the tab connecting portion (43).
  20. The battery cell according to any one of claims 1 to 19, wherein the tab connection portion (43) and the first tab (32) are welded to form a weld, and the weld and the guide portion (42) are disposed at a circumferential interval.

Description

Battery cell, battery and electricity utilization device Technical Field The application relates to the technical field of batteries, in particular to a battery monomer, a battery and an electric device. Background In recent years, new energy automobiles have been developed dramatically, and in the field of electric automobiles, a power battery plays an irreplaceable role as a power source of the electric automobile. Along with the great popularization of new energy automobiles, the demand for power battery products is also increasing, and batteries as core components of the new energy automobiles have higher requirements on use safety. However, how to improve the safety of the battery during use has been a problem in the industry. Disclosure of Invention The application aims to improve the working safety of a battery. According to a first aspect of the present application, there is provided a battery cell comprising: the shell comprises a first wall, and the first wall is provided with a pressure relief component; An electrode assembly disposed within the housing, the electrode assembly including an electrode body and a first tab leading from one end of the electrode body, and The first current collector is configured to electrically connect the first tab and the shell, and is at least partially positioned between the first tab and the pressure release component, at least one ventilation part and at least one guide part are arranged on the first current collector, the ventilation part penetrates through the first current collector along the thickness direction of the first wall, and the guide part is arranged in the peripheral area of the ventilation part. According to the embodiment, the ventilation part and the guide part are arranged on the first current collector close to the pressure release part, the guide part weakens the structural strength of the first current collector when pressure release is carried out, when the pressure is large, the first current collector can be guided to crack according to a preset path so as to deform or destroy, the exhaust area is increased, the ventilation part and the guide part can exhaust air simultaneously, the ventilation area of the pressure release part, which is reached by the gas in the electrode assembly, is increased, the pressure release part is prevented from being blocked, the gas can smoothly reach the pressure release part to be discharged out of the battery unit, the internal and external air pressure of the battery unit is balanced, the heat is timely discharged, and the safety of the battery unit in the use process is improved. In some embodiments, the guide includes at least one of a through hole or a score. According to the embodiment, the guide part is arranged as the through hole, and under the condition of thermal runaway, gas can more easily directly enter the through hole from the ventilation part so as to rapidly diffuse to surrounding areas, so that the exhaust speed is improved, the through hole can fully play a role when the internal gas pressure of the battery cell is relatively smaller, the gas can more smoothly reach the pressure release part to be discharged, the internal gas pressure and the external gas pressure of the battery cell are balanced, and the safety in the use process of the battery cell is improved. Or the guiding part is arranged as the notch, so that the strength weakening of the first current collector can be reduced, the strength of the first current collector is guaranteed, in addition, under the condition of thermal runaway, a strength weakening area is formed at the notch, the first current collector can be cracked along the notch, or further deformed at the notch, for example, the two sides of the notch are positioned at different heights, the exhaust area can be effectively increased, gas can more smoothly reach the pressure release part to be exhausted, and the internal and external air pressures of the battery cell are balanced, so that the safety of the battery cell in the use process is improved. In some embodiments, the guide extends in a radial direction of the first header. According to the embodiment, the guide part extends along the radial direction of the first current collector, so that gas can be guided from the central area of the first current collector to the periphery, the gas can be rapidly evacuated to prevent aggregation, the gas pressure near the ventilation part can be reduced, the exhaust speed is increased, the gas can reach the pressure release part more smoothly to be discharged out of the battery cell, the internal and external air pressures of the battery cell are balanced, and therefore the safety of the battery cell in the use process is improved. Furthermore, for a rolled electrode assembly, the first tab is of a multi-layered structure, and at least a portion of the welding marks are disposed in a radial direction in order to ensure reliable welding of each tab layer, such a guide p