Search

CN-122025990-A - Battery cell and battery pack

CN122025990ACN 122025990 ACN122025990 ACN 122025990ACN-122025990-A

Abstract

The invention relates to the technical field of batteries, in particular to a battery cell and a battery pack. The battery cell comprises a shell and a pressure release piece, wherein an exhaust part is formed on a first shell wall of the shell, the exhaust part is formed into a groove structure for thinning the first shell wall, the exhaust part is provided with a groove wall and a groove bottom, the pressure release piece is formed on the exhaust part in a punching mode, the pressure release piece and the first shell wall are integrally formed, the pressure release piece comprises a pressure release part and a connecting wall arranged around the circumferential outer edge of the pressure release part, the connecting wall is formed into an annular structure for connecting the groove bottom and the pressure release part, the pressure release part and the exhaust part are arranged at intervals in the thickness direction of the first shell wall, and the pressure release part is provided with a notch groove. According to the invention, the pressure release piece and the shell of the battery cell are formed into an integrated structure, and the welding process is omitted, so that the influence of the welding process on the stability and safety performance reduction of the pressure release piece is avoided, the safety performance of the battery cell is ensured, in addition, the assembly process of the battery cell is simplified, and the production efficiency is improved under the condition of improving the production quality.

Inventors

  • SUN CHAO

Assignees

  • 蜂巢能源科技股份有限公司

Dates

Publication Date
20260512
Application Date
20260414

Claims (10)

  1. 1. A kind of electric core, characterized by comprising the following steps: A housing having a first housing wall on which an exhaust portion is formed, the exhaust portion being formed in a groove structure of the first housing wall such that the exhaust portion has a groove wall and a groove bottom; The pressure relief piece is formed by stamping on the exhaust part, so that the pressure relief piece and the first shell wall are integrally formed, the pressure relief piece comprises a pressure relief part and a connecting wall arranged around the circumferential outer edge of the pressure relief part, the connecting wall is of an annular structure for connecting the bottom of the groove and the pressure relief part, the pressure relief part and the exhaust part are arranged at intervals in the thickness direction of the first shell wall, and the pressure relief part is provided with a notch groove.
  2. 2. The cell of claim 1, wherein the connecting wall comprises an extension portion connected to a bottom of the exhaust portion and a burring portion connecting the extension portion and the pressure relief portion, respectively, and wherein the burring portion gradually increases in size in a first direction along a direction in which the connecting wall protrudes out of the groove structure, such that a side of the connecting wall facing the pressure relief portion is formed in a flare structure.
  3. 3. The cell of claim 2, wherein an angle between the groove bottom and the flange portion is α,30 ° - α <90 °.
  4. 4. A cell according to any one of claims 1 to 3, wherein the circumferential edge of the pressure relief portion is bent away from the first housing wall to form a buffer zone such that the buffer zone is disposed at an angle to the surface of the pressure relief portion on which the score groove is disposed, the surface on which the score groove is disposed being disposed within the area enclosed by the connecting wall.
  5. 5. The cell of claim 1, wherein the first housing wall has a thickness dimension H in mm, the first housing wall has a first surface and a second surface disposed opposite to each other in a thickness direction thereof, the exhaust portion is formed by the first surface being recessed inward, a distance between the groove bottom and the second surface in the thickness direction of the first housing wall is H in mm, and 0.2≤h/h≤0.5.
  6. 6. The cell according to claim 5, it is characterized in that H is more than or equal to 1.5mm and less than or equal to 3mm.
  7. 7. The cell of claim 2, wherein a distance between the extension and the slot wall in the first direction is L,1.5mm +.l +.5 mm.
  8. 8. The cell of claim 1, wherein the pressure relief portion extends beyond an area enclosed by the slot wall such that the pressure relief portion protrudes from the first housing wall.
  9. 9. The cell of claim 1, wherein the housing comprises a shell and a cover assembly, and wherein the first housing wall is a cover body in the cover assembly or is disposed on the shell.
  10. 10. A battery pack comprising the cell of any one of claims 1 to 9.

Description

Battery cell and battery pack Technical Field The invention relates to the technical field of batteries, in particular to a battery cell and a battery pack. Background In the operation process of the battery, particularly in abnormal conditions such as overcharge, short circuit, high temperature and the like, the electrolyte can be decomposed and generate a large amount of gas, so that the internal pressure of the battery is increased, and when the pressure exceeds the pressure-resistant range of the battery shell, the shell can crack or even explode. The pressure release valve is arranged on the battery shell and is used for automatically opening before the pressure reaches a dangerous value so as to release internal gas to realize pressure release, thereby avoiding physical explosion of the battery. Usually, the assembly is realized in the welding of the shell or the top cap on relief valve and the battery, and the welding explodes the spot, welds the hole scheduling problem in the welding process unavoidable, influences the stability of welding yield and relief valve, and welded power control is not good, and the welding heat influence will lead to the explosion attenuation department deformation, the bending of relief valve, finally leads to relief valve security performance to appear the problem. Disclosure of Invention Therefore, the application aims to provide a battery cell and a battery pack, which are used for solving the problems that the safety performance and stability of a pressure release valve can be influenced and the safety of the battery cell cannot be effectively ensured due to the fact that the pressure release valve is welded with a shell or a top cover on the battery cell. The first aspect of the present invention provides a battery cell, which comprises: A housing having a first housing wall on which an exhaust portion is formed, the exhaust portion being formed in a groove structure of the first housing wall such that the exhaust portion has a groove wall and a groove bottom; The pressure relief piece is formed by stamping on the exhaust part, so that the pressure relief piece and the first shell wall are integrally formed, the pressure relief piece comprises a pressure relief part and a connecting wall arranged around the circumferential outer edge of the pressure relief part, the connecting wall is of an annular structure for connecting the bottom of the groove and the pressure relief part, the pressure relief part and the exhaust part are arranged at intervals in the thickness direction of the first shell wall, and the pressure relief part is provided with a notch groove. Preferably, the connecting wall comprises an extension part connected with the bottom of the exhaust part and a flanging part respectively connected with the extension part and the pressure relief part, and the dimension of the flanging part in the first direction is gradually increased along the direction that the connecting wall extends out of the groove structure, so that one side of the connecting wall facing the pressure relief part is formed into a flaring structure. Preferably, the angle between the groove bottom and the flanging part is alpha, and alpha is less than or equal to 30 degrees and less than 90 degrees. Preferably, the circumferential edge of the pressure relief portion is bent in a direction away from the first shell wall to form a buffer zone, so that the buffer zone and the surface of the pressure relief portion, on which the notch groove is arranged, are arranged at an angle, and the surface on which the notch groove is arranged in an area surrounded by the connecting wall. Preferably, the thickness dimension of the first shell wall is H in mm, the first shell wall is provided with a first surface and a second surface which are opposite to each other in the thickness direction, the exhaust part is formed by the first surface in an inward concave manner, the distance between the groove bottom and the second surface in the thickness direction of the first shell wall is H in mm, and H/H is more than or equal to 0.2 and less than or equal to 0.5. Preferably, H is 1.5 mm≤H is 3mm. Preferably, in the first direction, the distance between the extension portion and the groove wall is L, and L is more than or equal to 1.5mm and less than or equal to 5mm. Preferably, the pressure relief portion extends out of an area surrounded by the groove wall, so that the pressure relief portion protrudes out of the first shell wall. Preferably, the shell comprises a shell body and a cover plate assembly, and the first shell wall is a cover plate main body in the cover plate assembly or is arranged on the shell body. The second aspect of the invention provides a battery pack, which comprises the battery cell according to any one of the above technical schemes. Compared with the prior art, the invention has the beneficial effects that: The battery cell comprises a shell and a pressure relief piece, wherein an exh