Cover plate assembly, battery cell and battery pack

Abstract

The utility model discloses a cover plate assembly, a battery monomer and a battery pack, the cover plate assembly is used for the battery monomer, the cover plate assembly comprises a cover plate, an explosion-proof valve is arranged on the cover plate, and the explosion-proof valve and the cover plate are integrally formed; the protection part is connected with the cover plate and located on the side, away from the electrode assembly of the battery single body, of the cover plate, the protection part is provided with a protection cavity, the protection cavity is provided with a first opening facing the anti-explosion valve, and in a projection plane perpendicular to the thickness direction of the cover plate, the anti-explosion valve is located on the radial inner side of the first opening; the bottom wall of the side, right opposite to the first opening, of the protection cavity is a first bottom wall, at least one air hole penetrating through the first bottom wall in the thickness direction of the cover plate is formed in the first bottom wall, and the air holes penetrate through the edge of the first bottom wall. According to the cover plate assembly disclosed by the utility model, by arranging the protective piece, the probability that the explosion-proof valve is damaged by foreign matters and the probability that the explosion-proof valve is lapped with the electric connecting piece can be reduced, so that the safety of the battery pack is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a cover plate assembly, a battery cell and a battery pack. Background Art

[0002] The safety of batteries has always been a focus of everyone's attention. Battery cells are the basic components of batteries. In order to improve the safety of batteries, explosion-proof valves are installed on the battery cells. In related technologies, foreign objects in the battery pack can easily damage the explosion-proof valve, thereby affecting the safety of the battery. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model proposes a cover plate assembly, which can reduce production costs and improve the safety of a battery pack.

[0004] The utility model also provides a battery monomer having the cover plate assembly.

[0005] The utility model also provides a battery pack having the battery monomer.

[0006] According to the cover plate assembly of the first aspect of the utility model, the cover plate assembly is used for a battery cell, and the cover plate assembly comprises: a cover plate, on which an explosion-proof valve is provided; a protective member, the protective member is connected to the cover plate and is located on a side of the cover plate away from the electrode assembly of the battery cell, the protective member has a protective cavity, the protective cavity has a first opening arranged toward the explosion-proof valve, in a projection plane perpendicular to the thickness direction of the cover plate, the explosion-proof valve is located radially inside the first opening, the bottom wall of the protective cavity on one side opposite to the first opening is the first bottom wall, and at least one air vent is formed on the first bottom wall and passes through the first bottom wall along the thickness direction of the cover plate, and the air vent passes through the edge of the first bottom wall.

[0007] According to the cover plate assembly of the first aspect of the utility model, by providing a protective member, the probability of foreign matter damaging the explosion-proof valve and the probability of the explosion-proof valve overlapping the electrical connector can be reduced, thereby improving the safety of the battery pack; by providing air holes, the air pressure in the protective cavity and the battery pack can be maintained consistent, and the difficulty of high-temperature and high-pressure gas breaking through the protective member during thermal runaway can be reduced, thereby improving the reliability of the explosion-proof valve and the safety of the battery pack.

[0008] According to some embodiments of the present invention, a side surface of the cover plate away from the electrode assembly is a first surface, the explosion-proof valve protrudes from the first surface, and the protective member sets the explosion-proof valve cover inside the protective cavity through the protective cavity.

[0009] According to some embodiments of the utility model, the protective member includes: a substrate, on which the protective cavity is formed, and the protective cavity has the first opening and the second opening on both sides of the thickness direction of the cover plate; a covering plate, which is connected to the substrate and is located on the side of the substrate away from the cover plate, the covering plate covers the second opening, and the covering plate and the explosion-proof valve are arranged at intervals in the thickness direction of the cover plate.

[0010] According to some embodiments of the utility model, the substrate includes: a flat plate portion, which is arranged perpendicular to the thickness direction of the cover plate and connected to the first surface, and the flat plate portion is formed with a through hole that penetrates the flat plate portion along the thickness direction of the cover plate; an annular plate portion, which is arranged on the side of the flat plate portion away from the first surface and extends in a ring shape along the circumference of the through hole, the covering plate is arranged at one end of the annular plate portion away from the cover plate, and the explosion-proof valve is located radially inside the annular plate portion.

[0011] According to some embodiments of the present invention, the flat plate portion and the ring plate portion are integrally formed, or the flat plate portion and the ring plate portion are separate parts, and the flat plate portion and the ring plate portion are adhesively connected.

[0012] According to some embodiments of the present invention, the explosion-proof valve and the cover plate are integrally formed.

[0013] According to some embodiments of the present invention, the ventilation holes are formed as slits.

[0014] According to some embodiments of the utility model, in the thickness direction of the cover plate, the distance between the inner wall of the protection cavity and the explosion-proof valve is 0.5mm-0.8mm; and / or in the projection plane perpendicular to the thickness direction of the cover plate, the distance between the inner wall of the protection cavity and the explosion-proof valve is 0.5mm-1mm.

[0015] The battery cell according to the second aspect of the present invention comprises: the cover assembly according to the first aspect of the present invention; a shell having an installation cavity formed therein, the installation cavity having an opening, the cover assembly covering the opening; and an electrode assembly disposed in the installation cavity.

[0016] According to the battery cell of the second aspect of the present invention, by providing the cover plate assembly of the first aspect of the present invention, the production cost can be reduced and the safety can be improved.

[0017] A battery pack according to a third aspect of the present invention comprises: the battery cell according to the second aspect of the present invention.

[0018] According to the battery pack of the third aspect of the present invention, by providing the battery monomer according to the second aspect of the present invention, the production cost can be reduced and the safety can be improved.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic diagram of a cover plate assembly according to an embodiment of the utility model;

[0021] Figure 2 yes Figure 1 A cross-sectional view in the AA direction shown in FIG.

[0022] Figure 3 yes Figure 1 A schematic diagram of another angle of the cover assembly shown in ;

[0023] Figure 4 yes Figure 3 An exploded view of the cover assembly shown in ;

[0024] Figure 5 yes Figure 3 An exploded view of the guard shown in FIG.

[0025] Figure 6 yes Figure 5 Schematic diagram of the cover plate shown in .

[0026] Reference numerals:

[0027] 100. Cover plate assembly;

[0028] 10. Cover plate; 11. Explosion-proof valve; 12. First surface; 13. Pole hole;

[0029] 20. Protective member; 21. Protective cavity; 22. Base plate; 221. Flat plate portion; 222. Ring plate portion; 223. Pole through hole; 23. Cover plate; 231. Air vent; 232. Second adhesive member. DETAILED DESCRIPTION

[0030] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0031] Reference below Figure 1-Figure 6 A cover plate assembly 100 according to an embodiment of the first aspect of the present invention is described.

[0032] like Figure 1-Figure 3 As shown, the cap plate assembly 100 according to the first embodiment of the utility model is used for a battery cell, and the cap plate assembly 100 includes: a cap plate 10 and a protective member 20 .

[0033] Specifically, an explosion-proof valve 11 is provided on the cover plate 10, and the protective member 20 is connected to the cover plate 10 and is located on the side of the cover plate 10 away from the electrode assembly of the battery cell. The protective member 20 has a protective cavity 21, and the protective cavity 21 has a first opening arranged toward the explosion-proof valve 11. In the projection plane perpendicular to the thickness direction of the cover plate 10, the explosion-proof valve 11 is located on the radial inner side of the first opening, and the bottom wall on the side of the protective cavity 21 facing the first opening is the first bottom wall. At least one air hole 231 is formed on the first bottom wall and passes through the first bottom wall along the thickness direction of the cover plate 10. For example, the air hole 231 can be one, two, three or four, and the air hole 231 passes through the edge of the first bottom wall.

[0034] When a battery cell experiences thermal runaway, high-temperature and high-pressure gas will be generated inside the battery cell. Under the impact of the high-temperature and high-pressure gas, the explosion-proof valve 11 will open to form an explosion-proof hole on the cover plate 10. The high-temperature and high-pressure gas will rush out of the explosion-proof hole and break through the protective member 20, so that the high-temperature and high-pressure gas can be discharged from the battery cell.

[0035] It is understandable that as the battery pack is used for a longer time, there may be some movable foreign objects in the battery pack. For example, when the battery pack is opened for inspection, foreign objects may fall into the battery pack; during the use of the battery pack, some adhesive parts at the connection may be damaged and fall into the battery pack; when the exhaust channel of the battery pack is opened, the explosion-proof valve 11 will be connected to the outside world, and foreign objects may enter the battery pack from the exhaust channel. When foreign objects collide with the explosion-proof valve 11, the explosion-proof valve 11 may be damaged, causing the explosion-proof valve 11 to fail or even open incorrectly. During the use of the battery pack, vibrations will inevitably occur in the battery pack. During the vibration of the battery pack, the explosion-proof valve 11 may overlap with the electrical connector in the battery pack to cause electrical arcing, thereby affecting the safety of the battery pack.

[0036] In this embodiment, by providing the protective member 20, the protective member 20 can provide protection for the explosion-proof valve 11. It can be understood that the size of the foreign matter that can be moved in the battery pack is relatively small. When the foreign matter in the battery pack moves to the position of the explosion-proof valve 11, the protective member 20 can block the foreign matter, so that the foreign matter can be prevented from directly impacting the protective member 20, thereby reducing the probability of foreign matter damaging the explosion-proof valve 11. When the explosion-proof valve 11 is displaced with the vibration of the battery pack, the protective member 20 can prevent the explosion-proof valve 11 from contacting the electrical connector in the battery pack, thereby reducing the probability of the explosion-proof valve 11 overlapping the electrical connector in the battery pack.

[0037] During the use of the battery pack, the gas pressure of the battery pack will change continuously. By providing the air vent 231 , gas can pass through the air vent 231 , so that the gas pressure in the protection cavity 21 can be consistent with the gas pressure in the battery pack, thereby improving the reliability of the explosion-proof valve 11 .

[0038] The air hole 231 passes through the edge of the first bottom wall to reduce the connection strength between the first bottom wall and the side wall of the protective cavity 21. When the explosion-proof valve 11 is in an open state to form an explosion-proof hole, the high-temperature and high-pressure gas rushing out of the explosion-proof hole can more easily break through the protective part 20, so that the high-temperature and high-pressure gas can be discharged smoothly, thereby improving the safety of the battery pack.

[0039] According to the cover plate assembly 100 of the first aspect of the utility model, by providing the protective member 20, the probability of foreign matter damaging the explosion-proof valve 11 and the probability of the explosion-proof valve 11 overlapping the electrical connector can be reduced, thereby improving the safety of the battery pack; by providing the air vent 231, the air pressure in the protective cavity 21 and the battery pack can be maintained consistent, and the difficulty of high-temperature and high-pressure gas breaking through the protective member 20 during thermal runaway can be reduced, thereby improving the reliability of the explosion-proof valve 11 and the safety of the battery pack.

[0040] In some embodiments of the present invention, Figure 4 As shown, the side surface of the cover plate 10 away from the electrode assembly is the first surface 12, and the explosion-proof valve 11 protrudes from the first surface 12. In this way, the explosion-proof valve 11 does not occupy the layout space inside the battery cell, thereby facilitating the arrangement of components inside the battery cell and reducing the difficulty of product design.

[0041] The protective member 20 covers the explosion-proof valve 11 inside the protective cavity 21, so that there is a gap between the explosion-proof valve 11 and the inner wall of the protective cavity 21. When foreign objects hit the protective member 20, the protective member 20 has more deformation space, so that the protective member 20 can absorb more impact, further reducing the probability of damage to the explosion-proof valve 11 and improving the safety of the battery pack.

[0042] In some embodiments of the present invention, the cover plate 10 is made of aluminum material, which has a low density and stable chemical properties, thereby facilitating lightweighting of the battery pack and improving the reliability of the battery pack.

[0043] In some embodiments of the present invention, Figure 3 and Figure 4As shown, the protective member 20 includes: a substrate 22 and a cover plate 23. Specifically, a protective cavity 21 is formed on the substrate 22, and the protective cavity 21 has a first opening and a second opening on both sides of the thickness direction of the cover plate 10. The cover plate 23 is connected to the substrate 22 and is located on the side of the substrate 22 away from the cover plate 10. The cover plate 23 covers the second opening, and the cover plate 23 and the explosion-proof valve 11 are arranged at intervals in the thickness direction of the cover plate 10.

[0044] That is, the surface of one side of the cover plate 23 connected to the substrate 22 is formed as the bottom wall of the protection cavity 21, and the air hole 231 is formed on the cover plate 23, and the air hole 231 passes through the edge of the cover plate 23. Through the cooperation of the substrate 22 and the cover plate 23, the protective member 20 can cover the explosion-proof valve 11 inside the protection cavity 21, wherein the contact area between the substrate 22 and the cover plate 10 is large, which can improve the reliability of the connection between the protective member 20 and the cover plate 10, and the substrate 22 covers the surface of the cover plate 10 to protect the cover plate 10. In the process of generating the design, the size, shape or material properties of the substrate 22 and the cover plate 23 can be adjusted to meet more product design needs.

[0045] In some embodiments of the present invention, the substrate 22 is made of PC (Polycarbonate) material, which has stable chemical properties and high impact strength, thereby ensuring the protective effect of the protective element 20 .

[0046] In some embodiments of the present invention, the cover plate 23 is made of PET (polyethylene glycol terephthalate) material. PET material has stable chemical properties and high impact strength, thus ensuring the protective effect of the protective element 20.

[0047] In some embodiments of the present invention, Figure 3-Figure 5 As shown, the base plate 22 includes a flat plate portion 221 and an annular plate portion 222 .

[0048] Specifically, the flat plate portion 221 is arranged perpendicular to the thickness direction of the cover plate 10 and is connected to the first surface 12. The flat plate portion 221 is formed with a through hole that passes through the flat plate portion 221 along the thickness direction of the cover plate 10. The annular plate portion 222 is arranged on the side of the flat plate portion 221 away from the first surface 12 and extends in a ring shape along the circumference of the through hole. The covering plate 23 is covered on one end of the annular plate portion 222 away from the cover plate 10, and the explosion-proof valve 11 is located on the radial inner side of the annular plate portion 222.

[0049] Thus, the ring plate portion 222, the through hole and the cover plate 23 can define a protection cavity 21, wherein the flat plate portion 221 can provide support for the ring plate portion 222, the flat plate portion 221 can also provide protection for the cover plate 10, and the ring plate portion 222 can provide support for the cover plate 23. During the product design process, the size, relative angle or material properties of the flat plate portion 221, the ring plate portion 222 and the cover plate 23 can be adjusted to meet more product design requirements.

[0050] In some embodiments of the present invention, the flat plate portion 221 and the ring plate portion 222 are integrally formed, or the flat plate portion 221 and the ring plate portion 222 are separate parts, and the flat plate portion 221 and the ring plate portion 222 are bonded and connected.

[0051] When the flat plate portion 221 and the ring plate portion 222 are integrally formed, the number of operating procedures in the assembly process and the materials required to connect the flat plate portion 221 and the ring plate portion 222 can be reduced, thereby improving production efficiency and reducing production costs.

[0052] When the flat plate portion 221 and the ring plate portion 222 are separate parts, the combination of the flat plate portion 221 and the ring plate portion 222 can be adjusted according to the use requirements, so that the base plate 22 can adapt to more use requirements, reduce the number of molds in the product development process, and reduce production costs. Among them, the adhesive connection operation is convenient and the connection is reliable, which can improve production efficiency and ensure that the reliability of the connection between the flat plate portion 221 and the ring plate portion 222 meets the use requirements.

[0053] In some embodiments of the present invention, the flat plate portion 221 and the ring plate portion 222 are connected by a first adhesive, and the size of the first adhesive is not less than 1 mm in the direction perpendicular to the thickness direction of the cover plate 10. For example, the size of the first adhesive in the direction perpendicular to the thickness direction of the cover plate 10 can be 1 mm, 1.5 mm or 2 mm, thereby ensuring that the flat plate portion 221 and the ring plate portion 222 have a sufficient bonding area, so that the connection strength between the flat plate portion 221 and the ring plate portion 222 meets the use requirements.

[0054] In some embodiments of the present invention, Figure 6 As shown, the cover plate 23 and the ring plate portion 222 are connected by the second adhesive 232, so that the operation of connecting the cover plate 23 and the ring plate portion 222 is more convenient, which can improve the production efficiency. In the vertical direction of the thickness direction of the cover plate 10, the size a of the second adhesive 232 is not less than 1mm. For example, in the vertical direction of the thickness direction of the cover plate 10, the size a of the second adhesive 232 can be 1mm, 1.5mm or 2mm, thereby ensuring that the cover plate 23 and the ring plate portion 222 have a sufficient bonding area, so that the connection strength between the cover plate 23 and the ring plate portion 222 meets the use requirements.

[0055] In some embodiments of the present invention, the explosion-proof valve 11 and the cover plate 10 are integrally formed. By integrally forming the explosion-proof valve 11 and the cover plate 10, the connection between the explosion-proof valve 11 and the cover plate 10 is more reliable. In this way, during the use of the battery pack, the failure of the connection between the explosion-proof valve 11 and the cover plate 10 makes the probability of the explosion-proof valve 11 failing to function or even opening by mistake lower, thereby improving the safety of the battery pack during operation. At the same time, the one-piece molding has higher production efficiency and can save the operation process of connecting the explosion-proof valve 11 and the cover plate 10, thereby improving the production efficiency of the battery pack and reducing the production cost of the battery pack.

[0056] In some embodiments of the present invention, the cover plate 10 and the explosion-proof valve 11 are integrally stamped and formed. The integral stamping and forming has high efficiency and high product consistency, thereby improving production efficiency and improving the yield rate of the battery pack.

[0057] In some embodiments of the present invention, Figure 3 and Figure 6 As shown, the vent hole 231 is formed as a slit. In this way, it is easier to set the vent hole 231 on the cover plate 23 during the production process. At the same time, it is understandable that the vent hole 231 needs to have a sufficient ventilation area to maintain the same air pressure in the protection cavity 21 and the battery pack. By setting the vent hole 231 as a slit, when the ventilation area of ​​the vent hole 231 meets the use requirements, the size of the slit is small, thereby reducing the probability of foreign matter entering the protection cavity 21 from the vent hole 231, further reducing the probability of damage to the explosion-proof valve 11, and improving the safety of the battery pack.

[0058] Among them, preferably, the length b of the air hole 231 is 1.5mm-3mm, for example, the length b of the air hole 231 can be 1.5mm, 2mm or 3mm, and the width c of the air hole 231 is 0.1mm-0.3mm, for example, the width c of the air hole 231 can be 0.1mm, 0.15mm, 0.2mm or 0.3mm, thereby ensuring that the ventilation area of ​​the air hole 231 meets the use requirements and it is difficult for foreign matter to enter the protective cavity 21 through the air hole 231.

[0059] In some embodiments of the present invention, Figure 2 As shown, in the thickness direction of the cover plate 10 (eg Figure 2In the vertical direction shown in ), the distance d between the inner wall of the protection cavity 21 and the explosion-proof valve 11 is 0.5mm-0.8mm. For example, in the thickness direction of the cover plate 10, the distance d between the inner wall of the protection cavity 21 and the explosion-proof valve 11 can be 0.5mm, 0.6mm, 0.65mm or 0.8mm, thereby, in the thickness direction of the cover plate 10, the protective member 20 can have enough deformation space to absorb the impact of foreign objects, so that the protective effect of the protective member 20 on the explosion-proof valve 11 meets the use requirements.

[0060] In some embodiments of the present invention, Figure 2 As shown, in the projection plane perpendicular to the thickness direction of the cover plate 10, the spacing e between the inner wall of the protection cavity 21 and the explosion-proof valve 11 is 0.5mm-1mm. For example, in the projection plane perpendicular to the thickness direction of the cover plate 10, the spacing e between the inner wall of the protection cavity 21 and the explosion-proof valve 11 can be 0.5mm, 0.7mm, 0.75mm, 0.8mm or 1mm, thereby, in the direction perpendicular to the thickness direction of the cover plate 10, the protective member 20 can have enough deformation space to absorb the impact of foreign objects, so that the protective effect of the protective member 20 on the explosion-proof valve 11 meets the use requirements.

[0061] In some embodiments of the present invention, Figure 3 and Figure 4 As shown, the cover plate 10 is further provided with a pole hole 13, and the substrate 22 is provided with a pole through hole 223, and the pole hole 13 is directly opposite to the pole through hole 223, so that the pole of the battery cell can pass through the pole hole 13 and the pole through hole 223, so that the pole can be assembled on the battery cell, and the coverage area of ​​the substrate 22 on the cover plate 10 is larger, thereby improving the protection effect of the substrate 22 on the cover plate 10.

[0062] The battery cell according to the second embodiment of the utility model comprises: the cover plate assembly 100 according to the first embodiment of the utility model, a shell and an electrode assembly. An installation cavity is formed in the shell, the installation cavity has an opening, the cover plate assembly 100 is covered in the opening, and the electrode assembly is arranged in the installation cavity.

[0063] Among them, the shell can provide protection for the electrode assembly, and the electrode assembly can realize the charging and discharging functions of the battery cell.

[0064] According to the battery cell of the second embodiment of the utility model, by providing the cover plate assembly 100 according to the first embodiment of the utility model, the production cost can be reduced and the safety can be improved.

[0065] A battery pack according to an embodiment of the third aspect of the utility model includes: the battery cell according to the embodiment of the second aspect of the utility model.

[0066] According to the battery pack of the third embodiment of the utility model, by disposing the battery monomer according to the second embodiment of the utility model, the production cost can be reduced and the safety can be improved.

[0067] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0068] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0069] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0070] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0071] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A cover plate assembly, the cover plate assembly being used for a battery cell, characterized in that: include: A cover plate, wherein an explosion-proof valve is provided on the cover plate; a protective member connected to the cover plate and located on a side of the cover plate away from the electrode assembly of the battery cell, the protective member having a protective cavity, the protective cavity having a first opening arranged toward the explosion-proof valve, and the explosion-proof valve being located radially inward of the first opening in a projection plane perpendicular to the thickness direction of the cover plate, The bottom wall of the protection cavity facing the first opening is the first bottom wall, and at least one air hole penetrating the first bottom wall along the thickness direction of the cover plate is formed on the first bottom wall, and the air hole passes through the edge of the first bottom wall.

2. The cover plate assembly according to claim 1, characterized in that: A surface of the cover plate on one side away from the electrode assembly is a first surface, the explosion-proof valve protrudes from the first surface, and the protective member sets the explosion-proof valve cover inside the protective cavity.

3. The cover plate assembly according to claim 2, characterized in that: The protective element comprises: a substrate, on which the protection cavity is formed, and the protection cavity has the first opening and the second opening on both sides of the cover plate in the thickness direction; A covering plate is connected to the base plate and is located on a side of the base plate away from the cover plate. The covering plate covers the second opening. The covering plate and the explosion-proof valve are spaced apart in a thickness direction of the cover plate.

4. The cover plate assembly according to claim 3, characterized in that: The substrate comprises: A flat plate portion, the flat plate portion is arranged perpendicular to the thickness direction of the cover plate and connected to the first surface, and the flat plate portion is formed with a through hole penetrating the flat plate portion along the thickness direction of the cover plate; The annular plate portion is arranged on the side of the flat plate portion away from the first surface and extends in a ring shape along the circumference of the through hole. The covering plate cover is arranged at one end of the annular plate portion away from the cover plate. The explosion-proof valve is located radially inside the annular plate portion.

5. The cover plate assembly according to claim 4, characterized in that: The flat plate portion and the ring plate portion are integrally formed, or the flat plate portion and the ring plate portion are separate parts, and the flat plate portion and the ring plate portion are bonded and connected.

6. The cover plate assembly according to claim 1, characterized in that: The explosion-proof valve and the cover plate are integrally formed.

7. The cover plate assembly according to claim 1, characterized in that: The ventilation holes are formed as slits.

8. The cover plate assembly according to claim 1, characterized in that: In the thickness direction of the cover plate, the distance between the inner wall of the protection cavity and the explosion-proof valve is 0.5 mm-0.8 mm; and / or In a projection plane perpendicular to the thickness direction of the cover plate, the distance between the inner wall of the protection cavity and the explosion-proof valve is 0.5 mm-1 mm.

9. A battery cell, characterized in that: include: The cover plate assembly according to any one of claims 1 to 8; A housing, wherein a mounting cavity is formed in the housing, the mounting cavity has an opening, and the cover assembly is disposed to cover the opening; An electrode assembly is arranged in the installation cavity.

10. A battery pack, characterized in that: include: The battery cell according to claim 9.

Images