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CN-122025951-A - Battery cell cover plate and battery cell

CN122025951ACN 122025951 ACN122025951 ACN 122025951ACN-122025951-A

Abstract

The invention relates to the technical field of batteries, and provides a battery cell cover plate and a battery cell. The battery core cover plate comprises a cover plate body, a protection piece and a pole post, wherein a reference surface is formed on one side of the cover plate body, a supporting boss is formed on the reference surface, the supporting boss is convexly arranged on the reference surface, the protection piece is arranged on one side of the cover plate body, which is outwards formed with the supporting boss in the height direction, the protection piece is matched with the reference surface and the supporting boss in shape and covers the reference surface and the supporting boss, one end of the pole post penetrates through the reference surface and the protection piece, and the height of the supporting boss relative to the reference surface is larger than the height of the pole post, which is convexly arranged on the reference surface. The battery cell cover plate greatly reduces the risk of deformation, sealing failure or internal short circuit of the pole caused by direct force acting on the pole. Meanwhile, on the premise of not increasing the overall outline size of the cover plate, extra design freedom can be provided for the inside of the battery pack or the inside of the battery core. The cover plate outside reference surface and the support boss-adapted guard provide a protective layer for the entire cover plate outer surface.

Inventors

  • XIN XUEQIAN

Assignees

  • 蜂巢能源科技股份有限公司

Dates

Publication Date
20260512
Application Date
20260203

Claims (10)

  1. 1. A cell cover plate, comprising: A reference surface is formed on one side of the cover plate body, a support boss is formed on the reference surface, and the support boss is convexly arranged on the reference surface; The protection piece is arranged on one side of the cover plate body, which outwards forms the supporting boss in the height direction, the shape of the protection piece is matched with the datum plane and the supporting boss, and the protection piece covers the datum plane and the supporting boss; And one end of the pole penetrates through the datum plane and the protective piece, and the height of the supporting boss relative to the datum plane is larger than the height of the pole protruding out of the datum plane.
  2. 2. The cell cover of claim 1, wherein one of the guard and the cover body is provided with a clasp, the other is provided with a clasp hole adapted to the clasp, and the guard is secured to the cover body by the clasp and the clasp hole.
  3. 3. The cell cover plate according to claim 1, wherein the support boss is a tapered boss, an included angle between a side wall of the tapered boss and a direction perpendicular to the reference surface is β, and β is 20 ° or more and 25 ° or less.
  4. 4. The cell cover of claim 1, wherein the guard is notched in a position corresponding to the datum plane, the cell cover further comprising: the upper plastic is arranged on the reference surface and positioned in the notch, and one end of the pole penetrates through the cover plate body and is arranged in the upper plastic; The distance between the upper plastic and the supporting boss is a along the length direction of the cover plate body, and the distance a is more than or equal to 3mm and less than or equal to 5mm.
  5. 5. The battery cell cover plate according to claim 4, wherein the guard member is formed with a first retaining wall corresponding to the periphery of the notch and annularly arranged on the outer side of the upper plastic circumference; the distance of the first retaining wall in the height direction along the cover plate body is c, and c is more than or equal to 1.5mm and less than or equal to 2.5mm.
  6. 6. The cell cover plate according to claim 1, wherein the support boss is provided with a liquid injection hole, and the protection piece is provided with a through hole at a position corresponding to the liquid injection hole; at least one isolation groove is formed in the support boss on two sides of the liquid injection hole along the length direction of the cover plate body; The depth of the isolation groove is h, the width of the isolation groove along the length direction of the cover plate body is b, and the number of the isolation grooves is n, so that the isolation groove meets the requirement of 3.0mm 2 ≤nbh≤4.5mm 2 .
  7. 7. The cell cover plate according to claim 1, wherein an assembly gap is provided between the guard and the cover plate body, and the assembly gap is e, and satisfies 0.3 mm≤e≤0.5 mm.
  8. 8. The cell cover plate according to claim 1, wherein the support boss is provided with an explosion-proof valve, and the protection piece is provided with a second retaining wall corresponding to the periphery of the explosion-proof valve; the distance d between the second retaining wall and the cover plate body in the height direction is 0.8mm or more and 1.2mm or less.
  9. 9. The cell cover plate of claim 8, wherein the explosion-proof valve is covered with an explosion-proof valve patch; the protective piece is pressed on the explosion-proof valve patch at a position corresponding to the explosion-proof valve, and the distance between the edge of the explosion-proof valve patch and the explosion-proof valve in the width direction of the cover plate body is f, wherein f is more than or equal to 1.5mm.
  10. 10. A kind of electric core, characterized by comprising the following steps: The battery cell shell is provided with an opening; the cell cover plate according to any one of claims 1 to 9, wherein the cell cover plate is arranged on the opening and surrounds the cell shell to form a containing cavity; the pole group is arranged in the accommodating cavity, and the pole lugs of the pole group are connected with the pole posts.

Description

Battery cell cover plate and battery cell Technical Field The invention relates to the technical field of batteries, in particular to a battery cell cover plate and a battery cell. Background The lithium ion battery has become a core power source in the fields of electric automobiles, energy storage systems and the like by virtue of the advantages of high energy density, long cycle life and the like. The battery core is used as a basic unit of the lithium ion battery, and the structural design of the battery core is directly related to the overall performance, the safety and the energy density of the battery pack. The cover plate integrates a pole column, a liquid injection hole, an explosion-proof valve and other key functional areas which are electrically connected with the outside. The existing cell cover plate is generally of a flat plate-shaped structure, and the outer side surface of the existing cell cover plate is a plane. The pole is arranged protruding from the plane to realize welding connection with the conductive connecting piece in the battery pack. When the battery packs are in groups, the electric conduction connecting piece is stuck and fixed on the upper box body of the battery pack through the heat conduction adhesive, and a gap exists between a large-area except for the polar post on the cover plate and the upper box body, so that the battery packs are not in direct contact. This construction presents strength and safety risks in the first place. When the upper surface of the battery pack is impacted or extruded externally, external force directly acts on the pole through the conductive connecting piece, and the risk of loosening the pole, sealing failure of the cover plate and even internal short circuit of the battery core exists. Secondly, the heat dissipation efficiency problem. The heat of the cell during operation is mainly conducted to the upper box body through the polar post and the heat conducting glue coated on the conductive connecting piece for heat dissipation. Because the large-area of the cover plate is not contacted with the upper box body, the heat can be dissipated only through radiation and convection, the heat dissipation path is long, the thermal resistance is large, the heat accumulation of the battery core is caused, and the service life and the safety performance of the battery core are influenced. Furthermore, space utilization issues. At the battery package level, the clearance between two polar posts of the cover plate and the upper box occupies valuable longitudinal height space, and the improvement of the whole package energy density is limited. Disclosure of Invention The invention provides a battery cell cover plate and a battery cell, which are used for solving the problems of low strength, safety risk, low heat dissipation efficiency and low space utilization rate of the conventional battery cell cover plate. The invention provides a battery cell cover plate, comprising: A reference surface is formed on one side of the cover plate body, a support boss is formed on the reference surface, and the support boss is convexly arranged on the reference surface; The protection piece is arranged on one side of the cover plate body, which outwards forms the supporting boss in the height direction, the shape of the protection piece is matched with the datum plane and the supporting boss, and the protection piece covers the datum plane and the supporting boss; And one end of the pole penetrates through the datum plane and the protective piece, and the height of the supporting boss relative to the datum plane is larger than the height of the pole protruding out of the datum plane. According to the battery cell cover plate provided by the invention, one of the protection piece and the cover plate body is provided with the buckle, the other is provided with the clamping hole matched with the buckle, and the protection piece is fixed on the cover plate body through the buckle and the clamping hole. According to the battery cell cover plate provided by the invention, the supporting boss is a conical boss, the included angle between the side wall of the conical boss and the direction perpendicular to the reference surface is beta, and beta is more than or equal to 20 degrees and less than or equal to 25 degrees. According to the battery cell cover plate provided by the invention, the position of the protective piece corresponding to the reference surface is provided with a notch, and the battery cell cover plate further comprises: the upper plastic is arranged on the reference surface and positioned in the notch, and one end of the pole penetrates through the cover plate body and is arranged in the upper plastic; The distance between the upper plastic and the supporting boss is a along the length direction of the cover plate body, and the distance a is more than or equal to 3mm and less than or equal to 5mm. According to the battery cell cover plate provided by the inventi