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CN-121282432-B - Battery pack and power utilization device

CN121282432BCN 121282432 BCN121282432 BCN 121282432BCN-121282432-B

Abstract

The application discloses a battery pack and an electric device, wherein the battery pack comprises a box body, a heat exchange plate, a heat conducting piece and a battery pack, the box body comprises a bottom plate and a box body, the battery pack comprises a battery column formed by at least two single batteries, the single batteries are connected to the bottom plate, the single batteries comprise a shell, a cover plate and an electric core, the shell and the cover plate are welded to form a first welding wire, the electric core comprises a pole piece, a first side face of the shell is connected with the heat exchange plate through the heat conducting piece, the distance between the heat exchange plate and the first welding wire is dmm along a second direction, the distance between the heat exchange plate and the first welding wire is hmm along a third direction, x=d+h, the distance between the pole piece and the first welding wire is kmm, the projection overlapping area of a single battery column along the second direction and the heat exchange plate is S1mm 2 , the total area of the single heat exchange plate facing the first side face is Smm 2 , and x/(S1/S) is less than or equal to 25.

Inventors

  • LI XINJIAN
  • YIN XUCHENG

Assignees

  • 中创新航技术研究中心(深圳)有限公司
  • 中创新航科技集团股份有限公司

Dates

Publication Date
20260512
Application Date
20251209

Claims (20)

  1. 1. A battery pack, comprising: The box body comprises a bottom plate and a frame body which are connected with each other, a containing space is formed by the bottom plate and the frame body in a surrounding mode, and the thickness direction of the bottom plate is a third direction; The heat exchange plate is internally provided with a heat exchange flow channel for communicating a heat exchange medium, the heat exchange plate is arranged in the accommodating space and is connected with the bottom plate and/or the frame body, and the length direction of the heat exchange plate is a first direction; A heat conductive member; The battery pack is arranged at the upper part of the bottom plate and comprises a battery column formed by at least two single batteries arranged along the first direction, and the single batteries are connected to the bottom plate; the single battery comprises a shell, a cover plate and a battery cell, wherein the shell comprises at least one opening part, the cover plate is welded and connected with the opening part and is provided with a first welding wire, the shell and the cover plate enclose a containing cavity, the battery cell is arranged in the containing cavity and comprises a pole piece, and the first side surface of the shell is vertical to a bottom plate and is connected with the heat exchange plate through the heat conducting piece; The first direction, the third direction and the second direction are perpendicular to each other; the distance between the heat exchange plate and the first welding line is dmm along the second direction, the distance between the heat exchange plate and the first welding line is hmm along the third direction, x=d+h, the distance between the pole piece and the first welding line is kmm along the third direction, the area of the orthographic projection of the single battery column along the second direction, which is overlapped with the projection of the heat exchange plate, is S1mm 2 , the area of the single heat exchange plate facing the first side surface is Smm 2 , and the conditions are satisfied that x k/(S1/S) is less than or equal to 25 and less than or equal to 500; 0.3mm≤dmm≤2.6mm、5mm≤hmm≤25mm,3.5mm≤kmm≤15mm;0.72≤S1/S≤0.96。
  2. 2. The battery pack of claim 1, wherein the heat exchange plate forms a first region opposite the battery array, and wherein in the first region, a top surface of the heat exchange plate is lower than a top surface of the cover plate in a third direction.
  3. 3. The battery pack of claim 2, wherein, in the third direction, an end of the pole piece adjacent to the cover plate is a first pole piece end, the first pole piece end being located between the top surface of the cover plate and the top surface of the heat exchange plate.
  4. 4. The battery pack of claim 3, wherein the distance between the first pole piece end and the top surface of the heat exchange plate in the third direction is D1mm, satisfying 0mm < D1mm < 15mm.
  5. 5. The battery pack according to claim 2, wherein in the third direction, one end of the pole piece, which is close to the cover plate, is a first pole piece end, the top surface of the heat exchange plate is located between the first pole piece end and the top surface of the cover plate, and the distance between the top surface of the heat exchange plate and the first pole piece end is D2mm, so that the distance is 3.5 mm-15 mm and D2 mm-15 mm is satisfied.
  6. 6. The battery pack of claim 1, wherein the battery cell further comprises an electrical connector, the battery cell comprises a tab portion and a body portion, the tab portion is led out from at least one end of the body portion, the electrical connector is electrically connected to the tab portion, and at least a portion of the electrical connector is located between the top surface of the heat exchange plate and the first bonding wire in the third direction.
  7. 7. The battery pack according to claim 6, wherein the length dimension of the cover plate is L1mm and the dimension of the electrical connector is L2mm along the length direction of the cover plate, and the electrical connector satisfies 0.15≤L2/L1≤0.5.
  8. 8. The battery pack according to claim 1, further comprising a conductive bar, wherein the single battery further comprises a pole column arranged on the cover plate, one end of the pole column is electrically connected with the battery core, the other end of the pole column is welded with the conductive bar, the pole column and the conductive bar are welded to form a first welding surface, and the distance between the heat exchange plate and the first welding surface along the third direction is D3mm, so that the distance is 2mm less than or equal to D3mm less than or equal to 3.5mm.
  9. 9. The battery pack according to claim 1, wherein the heat exchange flow channel extends along the first direction, and the distance between the heat exchange flow channel closest to the first bonding wire and the first bonding wire in the heat exchange plate along the third direction is D4mm, and the distance is 5.3 mm-28 mm and is less than or equal to D4 mm.
  10. 10. The battery pack according to claim 9, wherein a first partition wall is provided between two adjacent heat exchange flow passages in the heat exchange plate in the third direction, and a distance between the first partition wall and the first bonding wire in the heat exchange plate closest to the first bonding wire is D5mm, satisfying that D5mm is 8 mm≤D5 mm≤30mm.
  11. 11. The battery pack according to any one of claims 1 to 10, wherein the heat exchange flow channel of the heat exchange plate is formed by enclosing a plurality of structural walls, and the wall thickness dimension of the structural walls is E1mm, so that E1mm is more than or equal to 0.3mm and less than or equal to 3mm.
  12. 12. The battery pack according to any one of claims 1 to 10, wherein the heat exchange plate is spaced from the bottom plate, the bottom surface of the unit cell is connected to the bottom plate, and the spacing distance between the heat exchange plate and the bottom plate in the third direction is D6mm, so that D6mm is 0.5mm or less and 15mm or less.
  13. 13. The battery pack according to any one of claims 1 to 10, wherein the heat conducting member is a heat conducting adhesive layer, the heat exchanging plate is connected with the first side surface of the shell through the heat conducting adhesive layer, and the thickness dimension of the heat conducting adhesive layer is E2mm, so that E2mm is more than or equal to 0.5mm and less than or equal to 2.5mm.
  14. 14. The battery pack according to claim 13, wherein the outer side of the battery cell is coated with an insulating film having a thickness dimension E3 μm satisfying E3 μm≤E3μm≤110 μm.
  15. 15. The battery pack of any one of claims 1-10, wherein the housing comprises two opposing first sides and two opposing second sides, the first sides and second sides disposed perpendicular to the base plate, the first sides being larger than the second sides, satisfying 10mm +.xm +.27.6 mm.
  16. 16. The battery pack of claim 1, wherein the housing includes two opposing first sides and two opposing second sides, the first and second sides disposed perpendicular to the base plate, the first side being smaller than the second side, satisfying 0.72≤S 1/S≤0.96.
  17. 17. The battery pack according to claim 15, wherein the heat exchange plate is internally provided with a plurality of heat exchange flow channels which are arranged at intervals along the third direction, and the distance between two adjacent heat exchange flow channels along the third direction is D7mm, so that D7mm is more than or equal to 0.3mm and less than or equal to 3mm.
  18. 18. The battery pack according to any one of claims 1 to 10, wherein the heat exchange plate has a thickness dimension E4mm, satisfying 2.5mm ∈4mm ∈25mm.
  19. 19. The battery pack of claim 1, wherein at least one end of the heat exchange plate exceeds an end of the battery pack in the first direction, and the heat exchange plate exceeds the end of the battery pack by a dimension Fmm, such that 25mm < Fmm < 70mm.
  20. 20. The battery pack of any one of claims 1-10, wherein the penetration direction of the first weld line is perpendicular to the top surface of the cover plate, and the penetration dimension of the first weld line is G1, satisfying 1mm ∈g1mm ∈4.5mm.

Description

Battery pack and power utilization device Technical Field The application relates to the technical field of batteries, in particular to a battery pack and an electric device. Background Along with the increasing of the fast charge demand of the battery, the temperature of the battery is rapidly increased in the high-power charge and discharge process, the safety risks such as thermal runaway are easily caused, and meanwhile, the charge and discharge efficiency is reduced. The battery temperature is raised too fast in the fast charging process, so that the charging time is prolonged, and potential safety hazards are increased. Disclosure of Invention The application aims to at least solve one of the technical problems in the prior art, and aims to provide a battery pack and an electric device with the battery pack, wherein the battery pack is beneficial to improving the heat radiation capability under the high-power quick-charging working condition and improving the charging efficiency and the safety. In order to solve the technical problems, the application provides a battery pack which comprises a box body, a heat exchange plate, a heat conducting piece and a battery pack; the box body comprises a bottom plate and a frame body which are connected with each other, an accommodating space is formed by the bottom plate and the frame body in a surrounding mode, and the thickness direction of the bottom plate is a third direction; a heat exchange flow channel is arranged in the accommodating space and used for communicating a heat exchange medium, the heat exchange plate is arranged in the accommodating space and connected with the bottom plate and/or the frame body, and the length direction of the heat exchange plate is a first direction; the battery pack is arranged on the upper portion of the bottom plate, the battery pack comprises a battery column formed by at least two single batteries arranged along the first direction, the single batteries are connected to the bottom plate, the single batteries comprise a shell, a cover plate and a battery cell, the shell comprises at least one opening, the cover plate is connected with the opening in a welding mode and is provided with a first welding wire, the shell and the cover plate enclose a containing cavity, the battery cell is arranged in the containing cavity, the battery cell comprises a pole piece, the first side face of the shell is perpendicular to the bottom plate and is connected with the heat exchange plate through the heat conducting piece, the first direction, the third direction and the second direction are perpendicular to each other, the distance between the heat exchange plate and the first welding wire is dmm along the second direction, the distance between the heat exchange plate and the first welding wire is hmm along the third direction, the distance between the pole piece and the first welding wire is kmm along the third direction, the projection area between the pole piece and the first welding wire is the projection area of the single battery 2 along the second direction is the projection area of S1mm, the area of the single heat exchange plate facing the first side surface is Smm 2, and the x k/(S1/S) is less than or equal to 25 and less than or equal to 500. Compared with the prior art, the battery pack has the beneficial effects that (1) the heat exchange plate is arranged along the first direction in an extending way and is connected with the first side surface of the single battery through the heat conducting piece, so that the heat exchange plate can exchange heat with the side surface of the single battery, the heat exchange contact area between the battery and the heat exchange plate is increased, the heat dissipation capability of the battery under the high-power quick-charging working condition is improved, the temperature rise of the battery is restrained, and the charging efficiency and the safety are improved. (2) According to the battery pack provided by the application, by limiting x k/(S1/S) to be less than or equal to 25 and less than or equal to 500, the heat exchange plate is ensured to be close to the main body of the single battery sufficiently so as to maintain high-efficiency heat conduction, the problem that the amplitude is large due to the arrangement of the heat exchange plate perpendicular to the bottom plate, the integral structural strength of the battery is influenced, and the risks of safety risk of cracking of the welding line between the shell and the cover plate and the like caused by the fact that the end part of the heat exchange plate is close to a mechanical and sealing weak area at the welding line are particularly avoided. When the battery pack is subjected to vibration, impact or thermal cycle working conditions, the local extrusion or shearing stress of the heat exchange plate to the welding line area can be reduced, faults such as welding line cracking and sealing failure caused by relative displac