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CN-224232666-U - Battery cell, battery device and electricity utilization device

CN224232666UCN 224232666 UCN224232666 UCN 224232666UCN-224232666-U

Abstract

The embodiment of the application discloses a battery cell, a battery device and an electricity utilization device. The first electrode assembly is accommodated in the case. The support wall is arranged opposite to the surface of the first electrode assembly, which has the largest surface area, and comprises two sub-walls and a support structure, wherein the two sub-walls are arranged opposite to each other along the first direction, and the support structure is respectively connected with the two sub-walls. The supporting structure is obliquely arranged relative to the two sub-walls, the supporting walls are compressed under the condition that the received pressure is greater than or equal to a first threshold value, so that the first electrode assembly can be restrained when the expansion force of the first electrode assembly is smaller, an expansion space is provided for the first electrode assembly when the expansion force of the first electrode assembly is larger, and the reliability of the whole cycle of the battery cell can be improved.

Inventors

  • ZHAO JIACHEN
  • XU LIANGFAN
  • Beng Jingjie
  • XU HU
  • LI XING
  • JIN HAIZU

Assignees

  • 宁德时代新能源科技股份有限公司

Dates

Publication Date
20260512
Application Date
20250408

Claims (19)

  1. 1. A battery cell, comprising: A housing (21); a first electrode assembly (221) housed in the case (21); A support wall (23), the support wall (23) being disposed within the housing (21), the support wall (23) being disposed opposite a surface of the first electrode assembly (221) having a largest surface area, the support wall (23) comprising two sub-walls (231) and a support structure (232), the two sub-walls (231) being disposed opposite each other along a first direction, the support structure (232) connecting the two sub-walls (231) respectively; Wherein the first direction is a thickness direction of the supporting wall (23), the supporting structure (232) is obliquely arranged relative to the two sub-walls (231), and the supporting wall (23) is compressed under the condition that the received pressure is larger than or equal to a first threshold value.
  2. 2. The battery cell according to claim 1, wherein an orthographic projection of the support wall (23) in the first direction covers an orthographic projection of a surface of the first electrode assembly (221) having the largest surface area in the first direction.
  3. 3. The battery cell according to claim 2, wherein an orthographic projection of the support wall (23) in the first direction covers an orthographic projection of the first electrode assembly (221) in the first direction.
  4. 4. The battery cell according to claim 1, wherein the support wall (23) is provided on both sides of the first electrode assembly (221) in the first direction, and the support wall (23) is located between the first electrode assembly (221) and the case (21).
  5. 5. The battery cell according to claim 4, wherein the housing (21) comprises: Two side walls which are oppositely arranged along the first direction; Wherein a distance between the two side walls is d1, a thickness of the first electrode assembly (221) along the first direction is d2, and a thickness d0 of the supporting wall (23) is 0.02d1≤d0≤0.97d1-d 2)/2.
  6. 6. The battery cell according to claim 1, wherein the support wall (23) is provided at one side of the first electrode assembly (221) in the first direction, and the support wall (23) is located between the first electrode assembly (221) and the case (21).
  7. 7. The battery cell according to claim 6, wherein the housing (21) comprises: Two side walls which are oppositely arranged along the first direction; Wherein a distance between the two side walls is d1, a thickness of the first electrode assembly (221) in the first direction is d2, and a thickness d0 of the support wall (23) satisfies that d0 is 0.04d1 is less than or equal to d0 is less than or equal to (0.97d1-d 2).
  8. 8. The battery cell of claim 1, wherein the battery cell further comprises: A second electrode assembly (222) housed in the case (21); Wherein the second electrode assembly (222) is disposed opposite to the surface of the first electrode assembly (221) having the largest surface area, and the support wall (23) is disposed between the first electrode assembly (221) and the second electrode assembly (222).
  9. 9. The battery cell according to claim 1, characterized in that the angle α1 of the support structure (232) with the two sub-walls (231) satisfies 15 ° - α1 +≤75° in case the support wall (23) is subjected to a pressure smaller than the first threshold value.
  10. 10. The battery cell of claim 1, wherein the first threshold is greater than or equal to 2000N and less than or equal to 6000N.
  11. 11. The battery cell according to claim 1, characterized in that the support wall (23) is fully compressed in case of a pressure being subjected to greater than or equal to a second threshold value.
  12. 12. The battery cell according to claim 11, characterized in that the angle α2 of the support structure (232) with the two sub-walls (231) satisfies 0 ° +.α2<15 ° in case the pressure to which the support wall (23) is subjected is greater than or equal to a second threshold value.
  13. 13. The battery cell of claim 11, wherein the second threshold is greater than or equal to 2500N and less than or equal to 9000N.
  14. 14. The battery cell according to any one of claims 1 to 13, wherein the material of the support wall (23) comprises: metal, plastic and high molecular organic matter.
  15. 15. The battery cell according to claim 14, wherein the substrate of the support wall (23) comprises aluminum.
  16. 16. The battery cell of any of claims 1-13, wherein the number of support structures (232) is greater than or equal to 2 and less than or equal to 50.
  17. 17. The battery cell according to any one of claims 1 to 13, wherein the support structure (232) is a support sloping plate, and the thickness d3 of the support sloping plate satisfies 0.2mm +.d3 +.2 mm.
  18. 18. A battery device, characterized in that the battery device comprises: The battery cell of any one of claims 1 to 17.
  19. 19. An electrical device, the electrical device comprising: The battery cell of any one of claims 1 to 17, wherein the battery cell is configured to provide electrical energy, or The battery device of claim 18, wherein the battery device is configured to provide electrical energy.

Description

Battery cell, battery device and electricity utilization device Technical Field The application relates to the field of batteries, in particular to a battery cell, a battery device and an electric device. Background In the current battery cell, the electrode assembly may be periodically expanded and contracted during charge and discharge, and if such expansion is not restrained at the initial stage of the battery cell cycle, there may be a risk of a decrease in the life of the battery cell. However, as the service life of the battery cell increases, the expansion amplitude of the electrode assembly gradually increases at the later cycle of the battery cell, and the electrode assembly may require a larger expansion space, and the introduction of a thicker buffer occupies a larger space, reducing the performance of the battery cell. Therefore, how to improve the reliability of the battery cell is a problem to be solved. Disclosure of utility model The embodiment of the application provides a battery cell, a battery device and an electricity utilization device, which can improve the reliability of the whole cycle of the battery cell. In a first aspect, a battery cell is provided that includes a housing, a first electrode assembly, and a support wall. The first electrode assembly is accommodated in the case. The support wall is arranged in the shell, the support wall is opposite to the surface with the largest surface area of the first electrode assembly, the support wall comprises two sub-walls and a support structure, the two sub-walls are oppositely arranged along the first direction, and the support structure is respectively connected with the two sub-walls. The first direction is the thickness direction of the supporting wall, the supporting structure is obliquely arranged relative to the two sub-walls, and the supporting wall is compressed under the condition that the pressure is greater than or equal to a first threshold value. According to the technical scheme provided by the embodiment of the application, the supporting walls are oppositely arranged on the surface with the largest surface area of the first electrode assembly, so that uniform binding force is provided for the first electrode assembly, and the problems of pole piece pleating and the like in the first electrode assembly are further improved. On the other hand, through setting up the bearing structure of slope between two sub-walls of the supporting wall, the supporting wall can be compressed under the condition that receives the pressure more than or equal to first threshold value to for the first electrode subassembly provides the space of inflation, alleviate the first electrode subassembly and receive the problem that concentrated stress arouses the lithium risk of separating out, and then can improve the reliability of battery single full cycle. In some embodiments, an orthographic projection of the support wall along the first direction covers an orthographic projection of a surface of the first electrode assembly having the largest surface area along the first direction. In the technical scheme provided by the embodiment of the application, the orthographic projection of the surface of the support wall with the largest surface area along the first direction covers the orthographic projection of the surface of the first electrode assembly with the largest surface area along the first direction, so that the possibility of damage caused by scraping the surface of the first electrode assembly with the support wall can be reduced, and the reliability of the battery cell can be improved. In some embodiments, the orthographic projection of the support wall in the first direction covers the orthographic projection of the first electrode assembly in the first direction. In the technical scheme provided by the embodiment of the application, under the condition that the orthographic projection of the supporting wall along the first direction covers the orthographic projection of the first electrode assembly along the first direction, even if the corner area of the first electrode assembly is extruded to the supporting wall, the corners of the supporting wall are not easy to scratch with the first electrode assembly, so that the reliability of the battery cell can be improved. In some embodiments, the support wall is disposed at both sides of the first electrode assembly in the first direction, and the support wall is located between the first electrode assembly and the case. According to the technical scheme provided by the embodiment of the application, the supporting walls are arranged on the two sides of the first electrode assembly along the first direction, and the supporting walls are positioned between the first electrode assembly and the shell, so that the balanced supporting force on the two sides can be provided for the first electrode assembly, the risk of uneven current density distribution caused by uneven stress of the first elec