Cover plate, cover plate assembly with cover plate and battery monomer

Abstract

The utility model discloses a cover plate, a cover plate assembly with the cover plate and a battery monomer, the cover plate comprises a cover plate body and a boss, and a pressure relief hole penetrating through the cover plate body along the thickness direction is formed on the cover plate body; the boss is arranged on the surface of one side, facing an electrode assembly of the single battery, of the cover plate body, and the boss is arranged on the periphery of the pressure relief hole and extends in the circumferential direction of the pressure relief hole. According to the cover plate, the boss is arranged on the peripheral edge of the pressure relief hole and extends in the peripheral direction of the pressure relief hole, so that when the peripheral edge of the explosion-proof valve is welded with the inner wall and / or the peripheral edge of the pressure relief hole of the cover plate, the strength of the peripheral area of the joint of the explosion-proof valve and the pressure relief hole can be enhanced; deformation of the area around the welding seam when the anti-explosion valve and the cover plate are welded is improved, internal stress on the anti-explosion valve is reduced, nick cracking and deformation of the anti-explosion valve are avoided, the heat dissipation area of the welding seam when the anti-explosion valve and the cover plate are welded can be increased, and then the welding seam quality is improved.

Description

Technical Field

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

[0002] Relevant technologies point out that the welding power around the cover plate is relatively high, generating a lot of heat. After welding, the explosion-proof valve shrinks when it is cold, causing deformation, resulting in large internal stress in the explosion-proof valve, and the notches on the explosion-proof valve become thinner or even crack. 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, which can strengthen the strength of the area around the connection between the explosion-proof valve and the pressure relief hole through a boss, thereby improving the deformation of the area around the weld when the explosion-proof valve and the cover plate are welded, reducing the internal stress on the explosion-proof valve, and avoiding the cracking and deformation of the explosion-proof valve.

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

[0005] The utility model also provides a battery monomer having the cover plate assembly.

[0006] According to the cover plate of the first aspect of the present invention, the cover plate includes: a cover plate body, on which is formed a pressure relief hole which passes through the cover plate body along the thickness direction; a boss, which is arranged on a side surface of the cover plate body facing the electrode assembly of the battery cell, and the boss is arranged on the periphery of the pressure relief hole and extends along the circumference of the pressure relief hole.

[0007] According to the cover plate of the embodiment of the utility model, by arranging a boss on the periphery of the pressure relief hole and extending it along the circumference of the pressure relief hole, when the periphery of the explosion-proof valve is welded to the inner wall and / or periphery of the pressure relief hole of the cover plate, not only can the strength of the area around the connection between the explosion-proof valve and the pressure relief hole be enhanced, the deformation of the area around the weld when the explosion-proof valve and the cover plate are welded can be improved, the internal stress on the explosion-proof valve can be reduced, and the notch cracking and deformation of the explosion-proof valve can be avoided, but also the heat dissipation area at the weld when the explosion-proof valve and the cover plate are welded can be increased, thereby improving the quality of the weld.

[0008] According to some embodiments of the utility model, the pressure relief hole is an oblong hole, and the two side edges of the pressure relief hole in the width direction are straight edges. The number of the bosses is two, and the two bosses are respectively arranged on the two straight edges and extend along the straight edges.

[0009] According to some embodiments of the present invention, in the length direction of the cover plate body, two ends of the boss respectively exceed two ends of the straight edge, and the boss is located between two ends of the pressure relief hole.

[0010] According to some embodiments of the present invention, in the width direction of the cover plate body, a side surface of the boss facing away from the pressure relief hole is flush with a side surface of the cover plate body.

[0011] According to some embodiments of the present invention, in a projection plane perpendicular to the thickness direction of the cover plate body, there is a gap between the boss and the inner wall of the pressure relief hole, and the gap is greater than or equal to 0.2 mm and less than or equal to 1 mm.

[0012] According to some embodiments of the present invention, in the thickness direction of the cover body, the ratio of the protrusion height of the boss to the thickness of the cover body is 0.1 to 0.6.

[0013] According to some embodiments of the utility model, the pressure relief hole includes an installation section and an exhaust section, the installation section is connected to a side of the exhaust section facing the electrode assembly, the cross-sectional size of the installation section is larger than the cross-sectional size of the exhaust section, and the installation section is configured to accommodate and fix an explosion-proof valve.

[0014] According to the cover plate assembly of the second aspect embodiment of the utility model, the cover plate assembly includes the cover plate and an explosion-proof valve according to the first aspect embodiment of the utility model, and the explosion-proof valve is arranged in the pressure relief hole and is welded to the cover plate.

[0015] According to the cover plate assembly of the embodiment of the utility model, by setting the cover plate of the above-mentioned first aspect embodiment, the boss is arranged at the periphery of the pressure relief hole and extends along the circumference of the pressure relief hole. When the periphery of the explosion-proof valve is welded to the inner wall and / or periphery of the pressure relief hole of the cover plate, it can not only enhance the strength of the area around the connection between the explosion-proof valve and the pressure relief hole, improve the deformation of the area around the weld when the explosion-proof valve and the cover plate are welded, reduce the internal stress on the explosion-proof valve, avoid cracking of the explosion-proof valve, but also increase the heat dissipation area at the weld when the explosion-proof valve and the cover plate are welded, thereby improving the quality of the weld.

[0016] According to some embodiments of the utility model, the cover plate assembly further includes: a lower insulating member, which is arranged on a side of the cover plate facing the electrode assembly, and an avoidance groove is formed on the lower insulator, and at least a portion of the boss is located in the avoidance groove.

[0017] According to a battery cell of an embodiment of the third aspect of the utility model, the battery cell includes a cover plate assembly according to an embodiment of the second aspect of the utility model.

[0018] According to the battery cell of the embodiment of the utility model, by setting the above-mentioned cover plate assembly, when the periphery of the explosion-proof valve is welded to the inner wall and / or periphery of the pressure relief hole of the cover plate, the strength of the area around the connection between the explosion-proof valve and the pressure relief hole can be improved, the deformation of the area around the weld when the explosion-proof valve and the cover plate are welded can be improved, the internal stress on the explosion-proof valve can be reduced, the cracking of the explosion-proof valve and the reduction of the opening pressure of the explosion-proof valve can be avoided, the leakage of the battery cell can be avoided, and the battery cell can be effectively protected.

[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 some embodiments of the utility model;

[0021] Figure 2 yes Figure 1 A top view of the cover plate and explosion-proof valve;

[0022] Figure 3 yes Figure 1 A cross-sectional view of the cover plate assembly in FIG.

[0023] Figure 4 yes Figure 1 A schematic diagram of the cover plate in FIG.

[0024] Figure 5 yes Figure 4 A top view of the cover plate in FIG.

[0025] Figure 6 yes Figure 4 A side view of the cover plate in FIG.

[0026] Figure 7 yes Figure 1 Schematic diagram of the lower insulator in FIG.

[0027] Reference numerals:

[0028] 100, cover plate; 10, cover plate body; 20, boss; 30, pressure relief hole; 31, installation section; 32, exhaust section; 1000, cover plate assembly; 200, explosion-proof valve; 300, lower insulating member; 301, avoidance groove. DETAILED DESCRIPTION

[0029] 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.

[0030] Reference below Figure 1-Figure 6 The cover plate 100 according to the first embodiment of the utility model is described.

[0031] like Figure 4 As shown, the cover plate 100 according to the first embodiment of the utility model includes: a cover plate body 10 and a boss 20.

[0032] Specifically, a pressure relief hole 30 is formed on the cover body 10 and passes through the cover body 10 in the thickness direction; the boss 20 is arranged on the side surface of the cover body 10 facing the electrode assembly of the battery cell, and the boss 20 is arranged on the periphery of the pressure relief hole 30 and extends along the circumference of the pressure relief hole 30.

[0033] Reference Figure 2 and Figure 4 As shown, the boss 20 is provided on the lower surface of the cover plate body 10, the electrode assembly is located on the lower side of the cover plate 100, the explosion-proof valve 200 is located in the pressure relief hole 30, the edge of the explosion-proof valve 200 is welded to the inner wall and / or the periphery of the pressure relief hole 30, a weld is formed at the welding position, and the boss 20 is provided at the periphery of the pressure relief hole 30 and extends along the circumference of the pressure relief hole 30. In this embodiment, by providing the boss 20, the strength of the peripheral area of ​​the weld can be enhanced, the deformation of the area around the weld when the explosion-proof valve 200 and the cover plate 100 are welded can be improved, and the deformation around the weld when the explosion-proof valve 200 and the cover plate 100 are welded can be reduced. The deformation amount transmitted to the explosion-proof valve 200 by the deformation around the weld when the explosion-proof valve 200 and the cover plate 100 are welded can be reduced, and the internal stress on the explosion-proof valve 200 can be reduced to prevent the explosion-proof valve 200 from cracking.

[0034] In addition, by providing a boss 20 on the side of the weld away from the explosion-proof valve 200, the heat dissipation area at the weld when the explosion-proof valve 200 and the cover plate 100 are welded can be increased, the deformation around the weld during welding can be reduced, and the internal stress on the explosion-proof valve 200 can be reduced to prevent the explosion-proof valve 200 from cracking.

[0035] According to the cover plate 100 of the embodiment of the utility model, by arranging the boss 20 on the periphery of the pressure relief hole 30 and extending along the circumference of the pressure relief hole 30, when the periphery of the explosion-proof valve 200 is welded to the inner wall and / or periphery of the pressure relief hole 30 of the cover plate 100, it can not only enhance the strength of the surrounding area of ​​the connection between the explosion-proof valve 200 and the pressure relief hole 30, improve the deformation of the area around the weld when the explosion-proof valve 200 and the cover plate 100 are welded, reduce the internal stress on the explosion-proof valve 200, avoid the cracking and deformation of the explosion-proof valve 200, but also increase the heat dissipation area at the weld when the explosion-proof valve 200 and the cover plate 100 are welded, thereby improving the quality of the weld.

[0036] According to some embodiments of the present invention, the pressure relief hole 30 is an oblong hole, and the two side edges of the pressure relief hole 30 in the width direction are straight edges. There are two bosses 20, and the two bosses 20 are respectively arranged on the two straight edges and extend along the straight edges.

[0037] Reference Figure 4 and Figure 5 As shown, the pressure relief hole 30 is an oblong hole, and the two side edges of the pressure relief hole 30 in the width direction are straight edges. Specifically, the front side wall and the rear side wall of the pressure relief hole 30 are planes extending along the left-right direction, and the left side wall and the right side wall of the pressure relief hole 30 are arc-shaped in cross-section in the horizontal direction. The edges adjacent to the front side wall and the rear side wall of the pressure relief hole 30 are straight edges of the pressure relief hole 30. The straight edges of the pressure relief hole 30 extend in a straight line extending in the left-right direction. Two bosses 20 are provided on the two straight edges and extend along the straight edges. The shapes of the pressure relief hole 30 and the bosses 20 are regular, which is convenient for processing.

[0038] The periphery of the explosion-proof valve 200 and the inner wall and / or periphery of the pressure relief hole 30 are welded to form a weld, and the weld includes: a first weld section, a second weld section, a third weld section and a fourth weld section. Among them, the weld formed at the rear side wall of the pressure relief hole 30 is the first weld section, and the first weld section extends along a straight line parallel to the left and right directions. The weld formed at the front side wall of the pressure relief hole 30 is the third weld section, and the first weld section extends along a straight line parallel to the left and right directions. The weld formed at the right side wall of the pressure relief hole 30 is the second weld section, and the second weld section is a circular arc weld convex to the right. The weld formed at the left side wall of the pressure relief hole 30 is the fourth weld section, and the fourth weld section is a circular arc weld convex to the left.

[0039] Among them, the distance between the second weld section and the right side of the cover plate 100 and the distance between the fourth weld section and the left side of the cover plate 100 are both large, and the left and right sides of the cover plate 100 are less affected during welding.

[0040] The distance between the first weld section and the rear edge of the cover plate 100 and the distance between the third weld section and the front edge of the cover plate 100 are both small. When no boss 20 extending along the straight edges is provided at the two straight edges, welding the first weld section and the third weld section will cause greater deformation of the front and rear edges of the cover plate 100.

[0041] In this embodiment, by arranging two bosses 20 respectively disposed on two straight edges and extending along the straight edges, the influence of welding the first weld section and the third weld section on the front side edge and the rear side edge of the cover plate 100 can be effectively reduced, and the structural strength of the area around the weld can be enhanced to reduce the deformation of the explosion-proof valve 200.

[0042] According to some embodiments of the present invention, in the length direction of the cover body 10 , two ends of the boss 20 respectively exceed two ends of the straight edge, and the boss 20 is located between two ends of the pressure relief hole 30 .

[0043] Reference Figure 5 As shown, the distance between the two ends of the boss 20 in the left-right direction is L, the distance between the two ends of the straight edge in the left-right direction is M, the distance between the two ends of the pressure relief hole 30 in the left-right direction is N, the length of the first weld section in the left-right direction and the length of the third weld section in the left-right direction are slightly larger than the distance between the two ends of the straight edge in the left-right direction, the length of the heat affected zone of the first weld section and the length of the heat affected zone of the second weld section are larger than the distance between the two ends of the straight edge in the left-right direction, the heat affected zone refers to the area where the metal on both sides of the weld undergoes changes in organization and performance due to the heat of welding, and the heat affected zone will deform.

[0044] In this embodiment, by making the two ends of the boss 20 in the left-right direction respectively exceed the two ends of the straight edge, the heat-affected zone of the first weld section and the heat-affected zone of the third weld section can be located within the length range of the boss 20, and the deformation of the heat-affected zone of the first weld section and the deformation of the heat-affected zone of the second weld section on the front side and the rear side of the cover plate 100 can be reduced, and the front side and the rear side of the cover plate 100 are prevented from bending and deforming. In addition, since the second weld section and the fourth weld section have a small influence on the edge of the cover plate 100, by setting the boss 20 between the two ends of the pressure relief hole 30 in the left-right direction, the structure of the boss 20 can be reduced, so that the layout design of the cover plate 100 is reasonable.

[0045] According to some embodiments of the present invention, in the width direction of the cover body 10 , a surface of the boss 20 that faces away from the pressure relief hole 30 is flush with a side surface of the cover body 10 .

[0046] Reference Figure 2-Figure 4 As shown, the front side surface of the boss 20 on the front side of the pressure relief hole 30 is flush with the front side surface of the cover plate 100, and the rear side surface of the boss 20 on the rear side of the pressure relief hole 30 is flush with the rear side surface of the cover plate 100, which can reduce the structural complexity of the cover plate body 10 and the boss 20 and facilitate the processing and production of the cover plate 100.

[0047] According to some embodiments of the present invention, in a projection plane perpendicular to the thickness direction of the cover body 10 , there is a gap between the boss 20 and the inner wall of the pressure relief hole 30 , and the gap is greater than or equal to 0.2 mm and less than or equal to 1 mm.

[0048] Reference Figure 3 and Figure 5As shown, the gap between the side surface of the boss 20 close to the pressure relief hole 30 and the inner wall of the pressure relief hole 30 is t, t is greater than or equal to 0.2 mm and less than or equal to 1 mm. For example, the t value can be 0.2 mm, 0.36 mm, 0.52 mm, 0.68 mm, 0.84 mm, or 1 mm.

[0049] In this embodiment, by setting the gap between the boss 20 and the inner wall of the pressure relief hole 30 to be greater than or equal to 0.2 mm and less than or equal to 1 mm, it can be ensured that the boss 20 can strengthen the structural strength of the area around the weld, reduce the deformation and internal stress of the explosion-proof valve 200, and at the same time make it convenient to perform welding operations and assemble the explosion-proof valve 200 at the welding point between the explosion-proof valve 200 and the cover plate 100. When the explosion-proof valve 200 and the cover plate 100 are welded by butt welding, since there is a gap between the boss 20 and the inner wall of the pressure relief hole 30, it is beneficial for the cover plate body 10 and the explosion-proof valve 200 on both sides of the weld to be heated evenly, ensuring that the connection between the explosion-proof valve 200 and the cover plate body 10 is welded through at the same time, thereby improving the welding quality.

[0050] According to some embodiments of the present invention, in the thickness direction of the cover body 10 , the ratio of the protrusion height of the boss 20 to the thickness of the cover body 10 is 0.1-0.6.

[0051] Reference Figure 3 and Figure 6 As shown, the protruding height of the boss 20 is m, the thickness of the cover body 10 is n, and the ratio of m to n ranges from 0.1 to 0.6. For example, the ratio of m to n can be 0.15, 0.25, 0.35, 0.45, and 0.55. By setting the ratio of m to n to be greater than or equal to 0.1, the structural strength of the boss 20 can be ensured, so that the boss 20 can ensure the structural strength of the area around the weld. Setting the ratio of m to n to be less than or equal to 0.6 and controlling the height of the boss 20 is conducive to reducing the size of the cover 100 and optimizing the structural layout of the cover 100.

[0052] According to some embodiments of the present invention, the pressure relief hole 30 may include a mounting section 31 and an exhaust section 32, the mounting section 31 is connected to the side of the exhaust section 32 facing the electrode assembly, the cross-sectional size of the mounting section 31 is larger than the cross-sectional size of the exhaust section 32, and the mounting section 31 is configured to accommodate and fix the explosion-proof valve 200.

[0053] like Figure 3 As shown, the mounting section 31 is located at the lower side of the exhaust section 32, and the cross-sectional size of the mounting section 31 is larger than the cross-sectional size of the exhaust section 32, so that the mounting section 31 can be formed with a groove structure. When the explosion-proof valve 200 is assembled, the upper surface of the explosion-proof valve 200 contacts the top wall of the mounting section 31, which is convenient for positioning the explosion-proof valve 200 during the assembly process. The outer peripheral surface of the explosion-proof valve 200 is connected to the inner wall of the mounting section 31 by welding.

[0054] In this embodiment, the pressure relief hole 30 includes a mounting section 31 and an exhaust section 32, and the cross-sectional size of the mounting section 31 is larger than the cross-sectional size of the exhaust section 32, so that a holding space can be provided for the explosion-proof valve 200, and the explosion-proof valve 200 can be positioned, which is beneficial to the assembly and welding of the explosion-proof valve 200 and improves the assembly efficiency.

[0055] According to the cover plate assembly 1000 of the second embodiment of the utility model, the cover plate assembly 1000 includes the cover plate 100 and the explosion-proof valve 200 according to the first embodiment of the utility model. The explosion-proof valve 200 is arranged in the pressure relief hole 30 and is welded to the cover plate 100.

[0056] Reference Figure 1 and Figure 2 As shown, the explosion-proof valve 200 is located in the pressure relief hole 30, and a weld is formed between the edge of the explosion-proof valve 200 and the peripheral edge of the pressure relief hole 30. The pressure relief hole 30 is an oblong hole, and the edges on both sides of the pressure relief hole 30 in the width direction are straight edges. There are two bosses 20, and the two bosses 20 are respectively arranged on the two straight edges and extend along the straight edges, which can enhance the strength of the peripheral area of ​​the weld, improve the deformation of the area around the weld when the explosion-proof valve 200 and the cover plate 100 are welded, and reduce the deformation around the weld when the explosion-proof valve 200 and the cover plate 100 are welded. The transmission of the explosion-proof valve 200 to the explosion-proof valve 200 can reduce the internal stress on the explosion-proof valve 200, avoid the explosion-proof valve 200 from cracking, and reduce the deformation of the edge of the cover plate 100.

[0057] According to the cover plate assembly 1000 of the embodiment of the utility model, by setting the cover plate 100 of the first aspect embodiment mentioned above, the boss 20 is arranged on the periphery of the pressure relief hole 30 and extends along the circumference of the pressure relief hole 30. When the periphery of the explosion-proof valve 200 is welded to the inner wall and / or periphery of the pressure relief hole 30 of the cover plate 100, it can not only enhance the strength of the surrounding area of ​​the connection between the explosion-proof valve 200 and the pressure relief hole 30, but also improve the deformation of the area around the weld when the explosion-proof valve 200 and the cover plate 100 are welded, reduce the internal stress on the explosion-proof valve 200, avoid cracking of the explosion-proof valve 200, avoid changes in the shape of the notch of the explosion-proof valve 200 and a reduction in the valve opening pressure of the explosion-proof valve 200, but also increase the heat dissipation area at the weld when the explosion-proof valve 200 and the cover plate 100 are welded, thereby improving the weld quality.

[0058] According to some embodiments of the present invention, the cover plate assembly 1000 may further include: a lower insulating member 300, which is arranged on the side of the cover plate 100 facing the electrode assembly, and an avoidance groove 301 is formed on the lower insulating member 300, and at least a portion of the boss 20 is located in the avoidance groove 301.

[0059] For example Figure 1As shown, the lower insulating member 300 is located at the lower side of the cover plate 100, and the electrode assembly is located at the lower side of the lower insulating member 300. The boss 20 can be completely located in the avoidance groove 301 of the lower insulating member 300. The avoidance groove 301 extends in the left-right direction and runs through the front side and the rear side of the lower insulating member 300. The avoidance groove 301 provides a holding space for the boss 20; the boss 20 can also be partially located in the avoidance groove 301 of the lower insulating member 300. At this time, the front side end face of the boss 20 will be located in front of the front side end face of the lower insulating member 300.

[0060] In this embodiment, by arranging the boss 20 in the avoidance groove 301, the end surface of the upper and lower insulating parts 300 close to the cover assembly 1000 can be fitted with the surface of the cover 100 close to the lower insulating part 300 in the thickness direction of the cover assembly 1000, so that the assembly of the cover assembly 1000 is more compact, and at the same time, it is beneficial for the lower insulating part 300 to protect the cover 100 and play an insulating role.

[0061] According to the battery cell of the embodiment of the third aspect of the utility model, the battery cell includes the cap plate assembly 1000 according to the embodiment of the second aspect of the utility model, and the cap plate assembly 1000 is located at the lower side of the battery cell.

[0062] According to the battery cell of the embodiment of the utility model, by setting the above-mentioned cover plate assembly 1000, when the periphery of the explosion-proof valve 200 is welded to the inner wall and / or periphery of the pressure relief hole 30 of the cover plate 100, the strength of the area around the connection between the explosion-proof valve 200 and the pressure relief hole 30 can be strengthened, thereby improving the deformation of the area around the weld when the explosion-proof valve 200 and the cover plate 100 are welded, reducing the internal stress on the explosion-proof valve 200, avoiding the cracking of the explosion-proof valve 200 and the reduction of the valve opening pressure of the explosion-proof valve 200, avoiding leakage of the battery cell, and effectively protecting the battery cell.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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, characterized in that: include: A cover plate body, wherein the cover plate body is formed with a pressure relief hole penetrating the cover plate body in a thickness direction; The boss is arranged on a side surface of the cover plate body facing the electrode assembly of the battery cell, and the boss is arranged on the periphery of the pressure relief hole and extends along the circumference of the pressure relief hole.

2. The cover plate according to claim 1, characterized in that: The pressure relief hole is an oblong hole, and the two side edges of the pressure relief hole in the width direction are straight edges. The number of the bosses is two, and the two bosses are respectively arranged on the two straight edges and extend along the straight edges.

3. The cover plate according to claim 2, characterized in that: In the length direction of the cover plate body, two ends of the boss respectively exceed two ends of the straight edge, and the boss is located between two ends of the pressure relief hole.

4. The cover plate according to claim 2, characterized in that: In the width direction of the cover plate body, a side surface of the boss facing away from the pressure relief hole is flush with a side surface of the cover plate body.

5. The cover plate according to claim 1, characterized in that: In a projection plane perpendicular to the thickness direction of the cover plate body, there is a gap between the boss and the inner wall of the pressure relief hole, and the gap is greater than or equal to 0.2 mm and less than or equal to 1 mm.

6. The cover plate according to claim 1, characterized in that: In the thickness direction of the cover plate body, the ratio of the protrusion height of the boss to the thickness of the cover plate body is 0.1 to 0.

6.

7. The cover plate according to claim 1, characterized in that: The pressure relief hole includes a mounting section and an exhaust section, wherein the mounting section is connected to a side of the exhaust section facing the electrode assembly, a cross-sectional dimension of the mounting section is larger than a cross-sectional dimension of the exhaust section, and the mounting section is configured to accommodate and fix an explosion-proof valve.

8. A cover plate assembly, characterized in that: It comprises a cover plate and an explosion-proof valve according to any one of claims 1 to 7, wherein the explosion-proof valve is arranged in the pressure relief hole and is welded to the cover plate.

9. The cover plate assembly according to claim 8, characterized in that: Also includes: A lower insulating member is provided on a side of the cover plate facing the electrode assembly, an escape groove is formed on the lower insulating member, and at least a portion of the boss is located in the escape groove.

10. A battery cell, characterized in that: Comprising the cover plate assembly according to claim 8 or 9.

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