Top cover assembly, battery cell and battery pack

Abstract

The utility model provides a top cover subassembly, battery cell and battery pack, the top cover subassembly includes cover plate, pole post plate and sealant, the cover plate is equipped with the through hole, the through hole is used for intercommunication with the inside of battery cell, pole post plate is installed on the cover plate and covers the through hole, and the pole post plate is equipped with the first glue overflow groove at the position corresponding to the through hole, the notch of the first glue overflow groove faces towards the through hole, and the sealant is arranged in the first glue overflow groove. The sealing glue is clamped between the cover plate and the pole column plate, and the first glue overflowing groove is partially filled with the sealing glue. According to the top cover assembly provided by the utility model, the technical problem that the sealant in the existing top cover assembly is easy to overflow through the through hole in the cover plate can be solved.

Description

Technical Field

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

[0002] In the related art, the battery cell includes a mounting shell, a core pack, and a top cover assembly. The mounting shell is provided with a mounting cavity and a top opening connected to the mounting cavity. The core pack is installed in the mounting cavity, and the top cover assembly covers the top opening of the mounting shell to protect the core pack. The top cover assembly includes a cover plate and a pole plate. The pole plate is pressed and mounted on the cover plate by sealant. The cover plate is provided with a through hole connected to the mounting cavity to facilitate electrical connection between the pole plate and the core pack. However, when the pole plate is pressed and mounted on the cover plate by sealant, the sealant easily overflows the cover plate through the through hole on the cover plate, resulting in an increase in the total thickness of the top cover assembly, which in turn takes up space in the mounting shell and reduces the energy density of the battery cell. Utility Model Content

[0003] The embodiments of the present invention provide a top cover assembly, a battery cell and a battery pack, which can improve the technical problem that the sealant in the existing top cover assembly easily overflows through the through holes on the cover plate.

[0004] In the first aspect, an embodiment of the present invention provides a top cover assembly, which includes a cover plate, a pole plate and a sealant. The cover plate is provided with a through hole, which is used to communicate with the interior of the battery cell. The pole plate is installed on the cover plate and covers the through hole, and the pole plate is provided with a first glue overflow groove at a position corresponding to the through hole, the notch of the first glue overflow groove faces the through hole, the sealant is clamped between the cover plate and the pole plate, and the sealant is partially filled in the first glue overflow groove.

[0005] In one embodiment, when the inner circumferential wall of the through hole is projected toward the pole plate along the thickness direction of the cover plate, the projection of the inner circumferential wall of the through hole is located in the first glue overflow groove, or the projection of the inner circumferential wall of the through hole coincides with the inner circumferential wall of the first glue overflow groove.

[0006] In one embodiment, the through hole and the first glue overflow groove are both circular in shape, and the inner diameter of the first glue overflow groove is greater than or equal to the inner diameter of the through hole.

[0007] In one embodiment, the pole plate has a first top surface and a first bottom surface opposite to each other along the thickness direction thereof, the first bottom surface faces the cover plate, the first glue overflow groove is recessed from the first bottom surface toward the majority of the first top surface, and the recessed depth of the first glue overflow groove is greater than 0 mm and less than or equal to 0.98 mm.

[0008] In one embodiment, an explosion-proof zone is formed on the pole plate at a position corresponding to the first glue overflow groove.

[0009] In one embodiment, a second glue overflow groove is further provided on the surface of the pole plate facing the cover plate, the second glue overflow groove extends along the outer peripheral edge of the pole plate, and the second glue overflow groove passes through the outer peripheral wall of the pole plate, and the sealant is also partially filled in the second glue overflow groove.

[0010] In one embodiment, a recessed depth of the second glue overflow groove is greater than 0 mm and less than or equal to 0.98 mm.

[0011] In one embodiment, the cover plate has a first outer periphery, the pole plate has a second outer periphery, and the sealant has a third outer periphery, and the third outer periphery is located between the first outer periphery and the second outer periphery; or, the cover plate, the pole plate and the sealant are all circular in shape, and the outer diameter of the sealant is larger than the outer diameter of the pole and smaller than the outer diameter of the cover plate.

[0012] In one embodiment, the pole plate is further provided with a connecting protrusion in the first glue overflow groove, and the connecting protrusion is used to electrically connect to the core package in the battery cell, and the sealant is arranged around the connecting protrusion; the inner peripheral wall of the sealant is located between the inner peripheral wall of the through hole and the outer peripheral wall of the connecting protrusion, or the outer shapes of the sealant, the through hole and the connecting protrusion are all circular, and the inner diameter of the sealant is greater than or equal to the outer diameter of the connecting protrusion, and smaller than the inner diameter of the through hole.

[0013] In one embodiment, the connecting protrusion protrudes from a notch of the first glue overflow groove.

[0014] In one embodiment, the pole plate has a first top surface and a first bottom surface opposite to each other along its thickness direction, the cover plate has a second top surface and a second bottom surface opposite to each other along its thickness direction, the sealant portion is sandwiched between the first bottom surface and the second top surface, and the sealant does not protrude from the first top surface and the first bottom surface.

[0015] In one embodiment, the thickness of the cover plate at any position thereof is greater than or equal to 0.05 mm and less than or equal to 1 mm, and / or the thickness of the pole plate at any position thereof is greater than or equal to 0.05 mm and less than or equal to 1 mm.

[0016] In the second aspect, an embodiment of the present invention provides a battery cell, which includes a mounting shell, a core pack and the top cover assembly described in any one of the above embodiments, the mounting shell is provided with a mounting cavity and an opening connected to the mounting cavity, the core pack is installed in the mounting cavity, the cover plate covers the opening, and the pole plate is electrically connected to the core pack at the through hole.

[0017] In a third aspect, an embodiment of the present invention provides a battery pack, which includes the battery cell as described in any of the above embodiments.

[0018] Beneficial effects of the embodiments of the present utility model:

[0019] In an embodiment of the present invention, a first glue overflow groove is provided on the pole plate, the first glue overflow groove is provided at a position corresponding to the through hole on the cover plate, and the notch of the first glue overflow groove faces the through hole on the cover plate, so that the first glue overflow groove forms a space for the sealant to overflow in a direction away from the through hole. When the pole plate is pressed onto the cover plate by the sealant, the sealant is more likely to overflow into the first glue overflow groove and partially fill the first glue overflow groove, that is, the sealant is not easy to overflow through the through hole on the cover plate, thereby avoiding the situation where the total thickness of the top cover assembly increases after pressing, thereby avoiding the top cover assembly from occupying too much space in the mounting shell, and ensuring the energy density of the battery cell.

[0020] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 This is a structural cross-sectional view of an embodiment of the top cover assembly of the present application;

[0023] Figure 2 yes Figure 1 Structural exploded diagram of the top cover assembly;

[0024] Figure 3 This is a structural cross-sectional view of an embodiment of a pole plate in a top cover assembly of the present application;

[0025] Figure 4 This is a structural cross-sectional view of an embodiment of the top cover assembly of the present application before being pressed together;

[0026] Figure 5 This is a structural cross-sectional view of an embodiment of a battery cell of the present application. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of the present application. In addition, it should be understood that the specific implementation described herein is only used to illustrate and explain the present application, and is not used to limit the present application. In the present application, the orientation words such as "upper" and "lower" generally refer to the upper and lower positions of the device in the actual use or working state, and specifically refer to the drawing direction in the drawings. The "inner" and "outer" refer to the outline of the device.

[0028] The first aspect is to improve the technical problem that the sealing glue in the existing top cover assembly is easy to overflow through the through hole on the cover plate, like Figure 1 The embodiment of the present application provides a top cover assembly 100, which comprises a cover plate 10, a pole plate 20 and sealing glue 30.

[0029] Among them, the structure of the top cover assembly 100 in the Figure 2 , Figure 2 The structure of the top cover assembly 100 in the Figure 1 is an exploded view, the cover plate 10 is provided with a through hole 11, the through hole 11 is used for communication with the inside of the battery cell 200, specifically, the top cover assembly 100 of the present application is applied to the cylindrical battery cell 200, the cover plate 10 is circular in shape, the through hole 11 penetrates the cover plate 10 along the thickness direction of the cover plate 10, and the through hole 11 is located at the center position of the cover plate 10, that is, the through hole 11 is coaxially arranged with the cover plate 10. For reference Figure 5 When the top cover assembly 100 is applied to the battery cell 200, the cover plate 10 is installed at the opening 212 of the mounting shell 210 to cover the opening 212 of the mounting shell 210, and the through hole 11 on the cover plate 10 is in communication with the mounting cavity 211 in the mounting shell 210, so as to facilitate the electrical connection between the core pack 220 in the mounting cavity 211 and the pole plate 20 mounted on the cover plate 10.

[0030] Of course, when it is necessary to apply the top cover assembly 100 to the square column battery cell 200 or other shaped battery cell 200, the shape of the cover plate 10 can be adaptively designed, such as being adaptively designed as a polygon, an ellipse and the like.

[0031] In addition, the shape of the through hole 11 can be circular, square or other shapes, as long as it is convenient for the pole plate 20 to be electrically connected with the tab of the core pack 220, such as in the present embodiment, the through hole 11 and the cover plate 10 are both circular to adapt to the cylindrical battery cell 200.

[0032] It should be noted that the cover plate 10 is made of a conductive material to facilitate electrical connection with the tabs of the core package 220. The cover plate 10 can be made of a metal material such as stainless steel, copper, iron, or aluminum alloy, or a conductive non-metallic material. Furthermore, the cover plate 10 can be made by processes such as stamping, turning, and cutting. The specific molding process can be flexibly selected based on actual conditions.

[0033] like Figure 1 As shown, the pole plate 20 is mounted on the cover plate 10 and covers the through hole 11 , and the pole plate 20 is provided with a first glue overflow groove 21 at a position corresponding to the through hole 11 , with the notch of the first glue overflow groove 21 facing the through hole 11 .

[0034] Specifically, the pole plate 20 is made of a conductive material to facilitate electrical connection with the tabs of the core package 220. The pole plate 20 can be made of a metal material such as stainless steel, copper, iron, or aluminum alloy, or a conductive non-metallic material. Furthermore, the pole plate 20 can be made by processes such as stamping, turning, and cutting. The specific molding process can be flexibly selected based on actual conditions.

[0035] During assembly, the pole plate 20 is fixed to the cover plate 10, and the area of ​​the pole plate 20 is larger than the area of ​​the through hole 11, so that the pole plate 20 can completely cover the through hole 11, ensuring the sealing of the battery cell 200. In this embodiment, the pole plate 20 and the through hole 11 are both circular and coaxially arranged. Of course, the pole plate 20 and the through hole 11 can also be set to different shapes, as long as the pole plate 20 can completely cover the through hole 11 on the cover plate 10.

[0036] Crucially, in this embodiment, the pole plate 20 has a first bottom surface 23 facing the cover plate 10, and the first bottom surface 23 is recessed with a first glue overflow groove 21 at a position corresponding to the through hole 11. The notch of the first glue overflow groove 21 faces the through hole 11, so that the first glue overflow groove 21 forms a space for the sealant 30 to overflow in a direction away from the through hole 11, thereby preventing the sealant 30 from overflowing from the through hole 11.

[0037] Specifically, such as Figure 4 As shown, when assembling the top cover assembly 100, the sealant 30 is first sandwiched between the cover plate 10 and the pole plate 20. The pole plate 20 is pressed on top of the sealant 30. The sealant 30 is partially located between the first overflow groove 21 and the through hole 11. At this time, the sealant 30 is a semi-solid glue. Then, the pole plate 20 can be pressurized against the sealant 30 by hot pressing or cold pressing. At this time, the sealant 30 will deform due to the pressure. Moreover, because the pole plate 20 presses the sealant 30 from top to bottom, and the first overflow groove 21 for overflowing is provided above the sealant 30, the sealant 30 is more likely to overflow into the first overflow groove 21. Figure 1As shown, after the lamination is completed, the sealant 30 partially fills the first overflow groove 21 .

[0038] That is to say, in the present application, by setting a first glue overflow groove 21 on the pole plate 20, the first glue overflow groove 21 is set at a position corresponding to the through hole 11 on the cover plate 10, and the notch of the first glue overflow groove 21 faces the through hole 11 on the cover plate 10, so that the first glue overflow groove 21 forms a space for the sealant 30 to overflow in a direction away from the through hole 11. When the pole plate 20 is pressed onto the cover plate 10 through the sealant 30, the sealant 30 is more likely to overflow into the first glue overflow groove 21 and partially fill the first glue overflow groove 21, that is, the sealant 30 is not easy to overflow through the through hole 11 on the cover plate 10, thereby avoiding the situation where the total thickness of the top cover assembly 100 increases after pressing, and further avoiding the top cover assembly 100 from occupying too much space in the mounting shell 210, thereby ensuring the energy density of the battery cell 200.

[0039] Optionally, in one embodiment, as Figure 1 As shown, when the inner circumferential wall of the through hole 11 is projected toward the pole plate 20 along the thickness direction of the cover plate 10 , the projection of the inner circumferential wall of the through hole 11 is located in the first glue overflow groove 21 , or the projection of the inner circumferential wall of the through hole 11 coincides with the inner circumferential wall of the first glue overflow groove 21 .

[0040] Specifically, in this embodiment, by making the area of ​​the first glue overflow groove 21 greater than or equal to the area of ​​the through hole 11, and making the first glue overflow groove 21 able to completely cover the through hole 11, it can be ensured that during pressing, the part of the sealant 30 located above the through hole 11 can overflow into the first glue overflow groove 21, thereby ensuring that the sealant 30 is not easy to overflow into the through hole 11.

[0041] For example, in a specific embodiment, the outer shapes of the through hole 11 and the first glue overflow groove 21 are both circular, the through hole 11 and the first glue overflow groove 21 are coaxially arranged, and the inner diameter of the first glue overflow groove 21 is greater than or equal to the inner diameter of the through hole 11, that is, when the inner diameter of the first glue overflow groove 21 is greater than the inner diameter of the through hole 11, the projection of the inner circumferential wall of the through hole 11 is located in the first glue overflow groove 21; when the inner diameter of the first glue overflow groove 21 is equal to the inner diameter of the through hole 11, the projection of the inner circumferential wall of the through hole 11 coincides with the inner circumferential wall of the first glue overflow groove 21.

[0042] Of course, in other specific embodiments, the shapes of the through hole 11 and the first glue overflow groove 21 may both be polygonal, elliptical, or other shapes, as long as the first glue overflow groove 21 can completely cover the through hole 11 .

[0043] Optionally, in one embodiment, as Figure 2As shown, the pole plate 20 has a first top surface 22 and a first bottom surface 23 opposite to each other along the thickness direction of the pole plate 20, the first bottom surface 23 faces the cover plate 10, the first overflow groove 21 is recessed from the first bottom surface 23 to the first top surface 22, and the recessed depth of the first overflow groove 21 is greater than 0 mm and less than or equal to 0.98 mm. The recessed depth can be 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 0.98 mm, etc.

[0044] It can be understood that if the recessed depth of the first overflow groove 21 is too large, the structural strength of the pole plate 20 will be affected. Therefore, by controlling the recessed depth of the first overflow groove 21 to be within 0.98 mm, the sealant 30 can be provided with an overflow space, and the structural strength of the pole plate 20 can be avoided from being affected.

[0045] It should be noted that when measuring the recessed depth of the first overflow groove 21, the bottom of the first overflow groove 21 is measured from the first bottom surface 23 along the thickness direction of the pole plate 20.

[0046] Optionally, in an embodiment, as shown in Figure 3 The pole plate 20 forms an explosion-proof area 24 at a position corresponding to the first overflow groove 21. Specifically, when the materials of the pole plate 20 and the cover plate 10 are the same, the thickness of the pole plate 20 in the explosion-proof area 24 is less than the thickness of the cover plate 10 at any position. In this way, the pole plate 20 at the explosion-proof area 14 is more easily broken by high-pressure gas, thereby achieving the effect of explosion-proof. Alternatively, the materials of the pole plate 20 and the cover plate 10 can be different, and the material of the pole plate 20 is more easily broken by high-pressure gas than the material of the cover plate 10. In addition, the position of the first overflow groove 21 on the pole plate 20 corresponds to the through hole 11 on the cover plate 10, so that the position corresponding to the through hole 11 on the pole plate 20 is relatively weak. Thus, the explosion-proof area 24 that can be broken by high-pressure gas is formed, thereby achieving the effect of explosion-proof.

[0047] In the present embodiment, the pole plate 20 is provided with a conductive connection area 25 and an explosion-proof area 24 at a position corresponding to the first overflow groove 21. The conductive connection area 25 is provided with a connecting protrusion 28, the connecting protrusion 28 extends from the bottom of the first overflow groove 21 to the through hole 11, and the connecting protrusion 28 is used for electrical connection with the core package 220.

[0048] The explosion-proof zone 24 is annular and is arranged around the conductive connection part. Crucially, the thickness of the pole plate 20 in the explosion-proof zone 24 is less than the thickness at any position on the cover plate 10. This makes the explosion-proof zone 24 the weakest position on the entire top cover assembly 100. When the pressure in the battery cell 200 is too high, the explosion-proof zone 24 will be broken through by the high-temperature and high-pressure gas in the battery cell 200, so that the pressure in the battery cell 200 is released to avoid explosion. At the same time, because the pole plate 20 is disconnected at the explosion-proof zone 24, the resistance of the entire circuit increases, close to a short circuit, blocking the heat generation reaction, and avoiding further increase in internal pressure of the battery to cause a violent explosion, thereby playing a role in safety and explosion protection.

[0049] That is, in this embodiment, the explosion-proof effect is achieved directly by setting the explosion-proof area 24 on the pole plate 20, so that the top cover assembly 100 does not need to set an explosion-proof valve at other positions, which simplifies the structure of the top cover assembly 100 and reduces production costs.

[0050] Optionally, in one embodiment, as Figure 1 As shown, the surface of the pole plate 20 facing the cover plate 10 (i.e., the first bottom surface 23) is further recessed with a second glue overflow groove 26, which extends along the outer periphery of the pole plate 20 and passes through the outer peripheral wall of the pole plate 20. The sealant 30 is also partially filled in the second glue overflow groove 26.

[0051] For details, please refer to Figure 4 If the second glue overflow groove 26 is not provided on the outer periphery of the pole plate 20, when the pole plate 20 is pressed downward to close the sealant 30, the portion of the sealant 30 not covered by the pole plate 20 will overflow upward. When the amount of overflowed glue is large, the height of the sealant 30 overflowing upward may be higher than the first top surface 22 of the pole plate 20, thereby increasing the total thickness of the top cover assembly 100.

[0052] In this embodiment, by providing a second glue overflow groove 26 on the outer periphery of the pole plate 20, reference can be made to Figure 4 When the pole plate 20 is pressed downward to close the sealant 30, the portion of the sealant 30 corresponding to the second overflow groove 26 will overflow upward and into the second overflow groove 26, thereby filling the second overflow groove 26. In other words, a portion of the overflowed sealant 30 will be confined within the second overflow groove 26, reducing the amount of sealant 30 overflowing outside the pole plate 20. This makes it less likely that the overflowed sealant 30 will protrude beyond the first top surface 22 of the pole plate 20, thereby preventing the total thickness of the top cover assembly 100 from exceeding a predetermined total thickness after assembly. In addition, the provision of the second overflow groove 26 can also prevent the sealant 30 from overflowing outside the pole plate 20, resulting in dimensional instability.

[0053] Optionally, in one embodiment, the recess depth of the second glue overflow groove 26 is greater than 0 mm and less than or equal to 0.98 mm. The specific recess depth can be 0.08 mm, 0.1 mm, 0.18 mm, 0.2 mm, 0.28 mm, 0.3 mm, 0.38 mm, 0.4 mm, 0.48 mm, 0.8 mm, 0.88 mm, 0.6 mm, 0.68 mm, 0.7 mm, 0.78 mm, 0.8 mm, 0.88 mm, 0.9 mm, 0.98 mm, etc.

[0054] It is understandable that if the recessed depth of the second glue overflow groove 26 is too large, it will affect the structural strength of the pole plate 20. Therefore, by controlling the recessed depth of the second glue overflow groove 26 within 0.98 mm, it can provide overflow space for the sealant 30 while avoiding affecting the structural strength of the pole plate 20.

[0055] It should be noted that when measuring the recessed depth of the second glue overflow groove 26 , it is necessary to measure from the first bottom surface 23 to the bottom of the second glue overflow groove 26 along the thickness direction of the pole plate 20 .

[0056] Optionally, in one embodiment, as Figure 1 As shown, the cover plate 10 has a first outer peripheral edge 12, the pole plate 20 has a second outer peripheral edge 27, and the sealant 30 has a third outer peripheral edge 31. The third outer peripheral edge 31 is located between the first outer peripheral edge 12 and the second outer peripheral edge 27. That is, the outer peripheral edge of the sealant 30 protrudes from the outer peripheral edge of the pole plate 20. In this way, good insulation can be achieved between the pole plate 20 and the cover plate 10, avoiding the situation where the pole plate 20 short-circuits with the cover plate 10 at its outer peripheral edge.

[0057] It should be noted that the shapes of the cover plate 10 , the pole plate 20 and the sealant 30 can be flexibly configured according to actual needs, as long as the third periphery is located between the first periphery and the second periphery.

[0058] For example, in a specific embodiment, the outer shapes of the cover plate 10, the pole plate 20 and the sealant 30 are all circular, and the outer diameter of the sealant 30 is larger than the outer diameter of the pole and smaller than the outer diameter of the cover plate 10, so that the third periphery can be located between the first periphery and the second periphery.

[0059] Of course, the outer shapes of the cover plate 10 , the pole plate 20 and the sealant 30 may also be polygonal, elliptical, etc., which are similar but of different sizes.

[0060] Optionally, in one embodiment, as Figure 1As shown, the pole plate 20 further has a connecting protrusion 28 protruding from the first glue overflow groove 21. The connecting protrusion 28 is used to electrically connect to the core package 220 in the battery cell 200. The sealant 30 is disposed around the connecting protrusion 28, and the inner peripheral wall of the sealant 30 is located between the inner peripheral wall of the through-hole 11 and the outer peripheral wall of the connecting protrusion 28. It can be understood that this allows the first glue overflow groove 21 to contain the overflow of the sealant 30, while also ensuring that a position (i.e., the connecting protrusion 28) is reserved on the pole plate 20 for electrical connection to the core package 220.

[0061] It should be noted here that the inner circumferential wall of the sealant 30, the outer circumferential wall of the connecting protrusion 28 and the inner circumferential wall of the through hole 11 can be circular, elliptical, polygonal or other shapes, as long as the inner circumferential wall of the sealant 30 is located between the inner circumferential wall of the through hole 11 and the outer circumferential wall of the connecting protrusion 28.

[0062] For example, in a specific embodiment, the outer shapes of the sealant 30, the through hole 11 and the connecting protrusion 28 are all circular, and the inner diameter of the sealant 30 is greater than or equal to the outer diameter of the connecting protrusion 28, and smaller than the inner diameter of the through hole 11, so that "the inner circumferential wall of the sealant 30 is located between the inner circumferential wall of the through hole 11 and the outer circumferential wall of the connecting protrusion 28" can be achieved.

[0063] Optionally, in one embodiment, as Figure 1 As shown, the connecting protrusion 28 protrudes from the notch of the first glue overflow groove 21. Since the first glue overflow groove 21 is recessed from the first bottom surface 23 to the first top surface 22 along the thickness direction of the pole plate 20, the connecting protrusion 28 protrudes from the notch of the first glue overflow groove 21, that is, protrudes from the first bottom surface 23 of the pole plate 20. It can be understood that this can prevent the sealant 30 from covering the lower surface of the connecting protrusion 28 during glue overflow, thereby affecting the electrical connection between the connecting protrusion 28 and the core package 220.

[0064] Optionally, in one embodiment, as Figure 1 As shown, the pole plate 20 has a first top surface 22 and a first bottom surface 23 opposite to each other along the thickness direction thereof, the cover plate 10 has a second top surface 13 and a second bottom surface 14 opposite to each other along the thickness direction thereof, and the sealant 30 is partially sandwiched between the first bottom surface 23 and the second top surface 13, and the sealant 30 does not protrude from the first top surface 22 and the first bottom surface 23. In this way, when producing the top cover assembly 100, the thickness dimension of the top cover assembly 100 can be better controlled to avoid the situation where the thickness dimension of the top cover assembly 100 is unstable during production.

[0065] Optionally, in one embodiment, the thickness of the cover 10 at any position thereof (except the through hole 11) is greater than or equal to 0.05 mm and less than or equal to 1 mm. The specific thickness can be 0.05 mm, 0.15 mm, 0.25 mm, 0.35 mm, 0.45 mm, 0.55 mm, 0.65 mm, 0.75 mm, 0.85 mm, 0.95 mm, 1 mm, etc.

[0066] It can be understood that if the thickness of the cover plate 10 is too small, the structural strength of the cover plate 10 will be weak and it will not be able to provide good protection; and if the thickness of the cover plate 10 is too large, the cover plate 10 will be too thick and heavy, which is not conducive to the lightweight design of the battery cell 200.

[0067] Therefore, this embodiment controls the thickness of the cover plate 10 at any position thereof to be between 0.05 mm and 1 mm, thereby ensuring the structural strength of the cover plate 10 and facilitating the lightweight and thin design of the top cover assembly 100 and the battery cell 200 .

[0068] Optionally, in one embodiment, the thickness of the pole plate 20 at any position thereof is greater than or equal to 0.05 mm and less than or equal to 1 mm, and the specific thickness can be 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, etc.

[0069] It is understandable that if the thickness of the pole plate 20 is too small, the structural strength of the pole plate 20 will be weak and it will not be able to provide good protection; and if the thickness of the pole plate 20 is too large, the pole plate 20 will be too thick and heavy, which is not conducive to the lightweight design of the battery cell 200.

[0070] Therefore, this embodiment controls the thickness of the pole plate 20 at any position thereof to be between 0.05 mm and 1 mm, thereby ensuring the structural strength of the pole plate 20 and facilitating a lightweight and thin design of the top cover assembly 100 and the battery cell 200 .

[0071] It should be noted here that because the pole plate 20 is provided with a first glue overflow groove 21, a second glue overflow groove 26, a connecting protrusion 28 and other structures, the thickness at different positions on the pole plate 20 can be different. For example, the thickness of the pole plate 20 at the first glue overflow groove 21 and the second glue overflow groove 26 is smaller, and the thickness at the position of the connecting protrusion 28 is larger. It is sufficient to control the thickness between 0.05 mm and 1 mm.

[0072] Second, as Figure 5As shown, an embodiment of the present invention provides a battery cell 200, which includes a mounting shell 210, a core pack 220 and a top cover assembly 100, wherein the mounting shell 210 is provided with a mounting cavity 211 and an opening 212 connected to the mounting cavity 211, and the core pack 220 is installed in the mounting cavity 211. The core pack 220 is mainly wound by a positive electrode sheet, a negative electrode sheet and a diaphragm, and is a component that produces an electrochemical reaction in the battery cell 200. The specific structure of the core pack 220 can refer to the relevant existing technology and will not be described in more detail here. The specific structure of the top cover assembly 100 refers to the above embodiment, and the cover plate 10 in the top cover assembly 100 covers the opening 212, thereby completely closing the mounting cavity 211, and the pole plate 20 is electrically connected to the core pack 220 at the through hole 11.

[0073] It can be understood that since the battery cell 200 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0074] Optionally, in one embodiment, as Figure 5 As shown, the core package 220 is provided with a first pole ear 221 and a second pole ear 222, one of the first pole ear 221 and the second pole ear 222 is a positive pole ear, and the other is a negative pole ear. The first pole ear 221 is electrically connected to the pole plate 20, and the second pole ear 222 is clamped between the outer peripheral wall of the cover plate 10 and the inner peripheral wall of the installation cavity 211, and the pole ear is electrically connected to the cover plate 10, so that the core package 220 can be connected to the external circuit through the pole plate 20 and the cover plate 10.

[0075] It can be understood that in this embodiment, the second pole ear 222 is clamped between the outer peripheral wall of the cover plate 10 and the inner peripheral wall of the installation cavity 211. In this way, when the top cover assembly 100 is installed, the electrical connection between the second pole ear 222 and the cover plate 10 can be achieved, which simplifies the assembly process and thus improves production efficiency.

[0076] Optionally, in one embodiment, as Figure 5 As shown, a folding portion 15 is provided on the outer periphery of the cover plate 10, and the folding portion 15 is folded upward, and extends parallel to the inner peripheral wall of the mounting cavity 211, and the folding portion 15 is in contact with the inner peripheral wall of the mounting cavity 211, and the second pole ear 222 is sandwiched between the folding portion 15 and the inner peripheral wall of the mounting cavity 211.

[0077] It can be understood that in this embodiment, a folding portion 15 is provided on the outer periphery of the cover plate 10 so that the cover plate 10 can increase the contact area with the mounting shell 210 through the folding portion 15, thereby making the top cover assembly 100 more stably installed on the mounting shell 210.

[0078] On the third aspect, an embodiment of the present invention provides a battery pack (not shown), which includes a battery cell 200 as in any of the above embodiments, and the battery cell 200 includes a top cover assembly 100 as in any of the above embodiments. Since the battery pack adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be repeated here one by one.

[0079] The above is a detailed introduction to the embodiments of the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, based on the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A top cover assembly, characterized in that: include: The cover plate is provided with a through hole, wherein the through hole is used to communicate with the interior of the battery cell; a pole plate, mounted on the cover plate and covering the through hole, wherein the pole plate is provided with a first glue overflow groove at a position corresponding to the through hole, with the notch of the first glue overflow groove facing the through hole; and The sealant is sandwiched between the cover plate and the pole plate, and the sealant is partially filled in the first overflow groove.

2. The top cover assembly according to claim 1, wherein: When the inner circumferential wall of the through hole is projected toward the pole plate along the thickness direction of the cover plate, the projection of the inner circumferential wall of the through hole is located in the first glue overflow groove, or the projection of the inner circumferential wall of the through hole coincides with the inner circumferential wall of the first glue overflow groove.

3. The top cover assembly according to claim 1, wherein: The through hole and the first glue overflow groove are both circular in shape, and the inner diameter of the first glue overflow groove is greater than or equal to the inner diameter of the through hole.

4. The top cover assembly according to claim 1, wherein: The pole plate has a first top surface and a first bottom surface opposite to each other along its thickness direction, the first bottom surface faces the cover plate, the first glue overflow groove is recessed from the first bottom surface to the majority of the first top surface, and the recessed depth of the first glue overflow groove is greater than 0 mm and less than or equal to 0.98 mm.

5. The top cover assembly according to claim 1, wherein: An explosion-proof zone is formed on the pole plate at a position corresponding to the first glue overflow groove.

6. The top cover assembly according to any one of claims 1 to 5, characterized in that: A second glue overflow groove is further provided on the surface of the pole plate facing the cover plate. The second glue overflow groove extends along the outer periphery of the pole plate and passes through the outer peripheral wall of the pole plate. The sealant is also partially filled in the second glue overflow groove.

7. The top cover assembly according to claim 6, wherein: The recessed depth of the second glue overflow groove is greater than 0 mm and less than or equal to 0.98 mm.

8. The top cover assembly according to any one of claims 1 to 5, characterized in that: The cover plate has a first outer periphery, the pole plate has a second outer periphery, and the sealant has a third outer periphery, and the third outer periphery is located between the first outer periphery and the second outer periphery; Alternatively, the outer shapes of the cover plate, the pole plate and the sealant are all circular, and the outer diameter of the sealant is larger than the outer diameter of the pole and smaller than the outer diameter of the cover plate.

9. The top cover assembly according to claim 8, wherein: The pole plate is further provided with a connecting protrusion in the first glue overflow groove, the connecting protrusion being used to electrically connect to the core package in the battery cell, and the sealant is arranged around the connecting protrusion; The inner circumferential wall of the sealant is located between the inner circumferential wall of the through hole and the outer circumferential wall of the connecting protrusion, or the outer shapes of the sealant, the through hole and the connecting protrusion are all circular, and the inner diameter of the sealant is greater than or equal to the outer diameter of the connecting protrusion and smaller than the inner diameter of the through hole.

10. The top cover assembly according to claim 9, wherein: The connecting protrusion protrudes from the notch of the first glue overflow groove.

11. The top cover assembly according to any one of claims 1 to 5, characterized in that: The pole plate has a first top surface and a first bottom surface opposite to each other along its thickness direction, the cover plate has a second top surface and a second bottom surface opposite to each other along its thickness direction, the sealant portion is sandwiched between the first bottom surface and the second top surface, and the sealant does not protrude from the first top surface and the first bottom surface.

12. The top cover assembly according to any one of claims 1 to 5, characterized in that: The thickness of the cover plate at any position thereof is greater than or equal to 0.05 mm and less than or equal to 1 mm, and / or the thickness of the pole plate at any position thereof is greater than or equal to 0.05 mm and less than or equal to 1 mm.

13. A battery cell, characterized in that: include: A mounting shell having a mounting cavity and an opening communicating with the mounting cavity; A core package is installed in the installation cavity; as well as, The top cover assembly according to any one of claims 1 to 12, wherein the cover plate covers the opening, and the pole plate is electrically connected to the core package at the through hole.

14. A battery pack, characterized in that: Comprising the battery cell as claimed in claim 13.

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