Cover plate assembly of battery cell, battery cell, battery pack, and electric device

Abstract

A cover plate assembly of a battery cell, a battery cell, a battery pack, and an electric device. The cover plate assembly of the battery cell comprises a cover plate body, a terminal assembly and an explosion-proof valve. Both the terminal assembly and the explosion-proof valve are arranged on the cover plate body, and the terminal assembly is adapted to be electrically connected to an electrode core. On the same projection plane, the orthographic projection area of the explosion-proof valve is S1, and the orthographic projection area of the cover plate assembly is S, where S1 = 0.2S - 0.8S, S and S1 are in the same unit, and the projection plane is perpendicular to the direction of thickness of the cover plate body.

Description

Cover plate assembly of battery monomer, battery monomer, battery pack and electric device

[0001] The present application claims priority to the Chinese patent application No. 2024104744283, filed on April 18, 2024, and entitled "Cover plate assembly of battery monomer, battery monomer, battery pack and electric device", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of battery, in particular to a cover plate assembly of battery monomer, a battery monomer, a battery pack and an electric device. BACKGROUND

[0003] The inside of the battery monomer has a large amount of chemical substances, and a large amount of mixed gas and liquid is easily generated during the charging and discharging process, accompanied by continuously accumulated pressure. If these pressures are not balanced or released in time, it is easy to cause the shell of the battery monomer to deform and leak liquid, and even cause the battery to explode in severe cases.

[0004] In the prior art, in order to solve the above problems, an explosion-proof valve is usually arranged on the cover plate assembly of the battery monomer. The explosion-proof valve can be used to realize rapid exhaust and pressure relief of the battery monomer, so as to play a role in explosion-proof, and to a certain extent, solve the technical problem of self-explosion of the battery monomer.

[0005] However, the area of the explosion-proof valve on the existing cover plate assembly is small, which affects the pressure relief capacity of the explosion-proof valve, thereby reducing the use safety of the battery monomer. SUMMARY

[0006] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the first object of the present application is to provide a cover plate assembly of a battery monomer, which is provided with a large-area explosion-proof valve to improve the use safety of the battery monomer, and solves the technical problem that the area of the explosion-proof valve in the prior art affects the pressure relief capacity of the explosion-proof valve.

[0007] The second object of the present application is to provide a battery monomer with the above-mentioned cover plate assembly.

[0008] The third object of the present application is to provide a battery pack with the above-mentioned battery monomer.

[0009] The fourth object of the present application is to provide an electric device with the above-mentioned battery pack.

[0010] The cover plate assembly of the battery cell according to the embodiment of the present application comprises: a cover plate body; a pole assembly and an explosion-proof valve, both of which are arranged on the cover plate body, and the pole assembly is adapted to be electrically connected with a pole core; on the same projection plane, the normal projection area of the explosion-proof valve is S1, and the normal projection area of the cover plate assembly is S, wherein S1 = 0.2S-0.8S, S and S1 have the same unit, and the projection plane is perpendicular to the thickness direction of the cover plate body.

[0011] The cover plate assembly of the battery cell according to the embodiment of the present application sets the normal projection area S1 of the explosion-proof valve in the thickness direction perpendicular to the cover plate body to be 0.2-0.8 times the normal projection area S of the cover plate assembly in the thickness direction perpendicular to the cover plate body, so that a large-size explosion-proof valve can be arranged on the cover plate body, the pressure relief capacity of the explosion-proof valve is improved, and the use safety of the battery cell is improved.

[0012] In some embodiments, S1 = 0.2S-0.5S.

[0013] In some embodiments, on the projection plane, the normal projection of the pole assembly deviates from the center of the normal projection outer contour of the cover plate body, the side of the normal projection of the pole assembly close to the center of the normal projection outer contour of the cover plate body is a first side, and the normal projection of the explosion-proof valve is arranged close to the first side.

[0014] In some embodiments, on the projection plane, the minimum distance between the normal projection outer contour of the explosion-proof valve and the center of the normal projection outer contour of the cover plate body is a first distance, the minimum distance between the normal projection outer contour of the pole assembly and the center of the normal projection outer contour of the cover plate body is a second distance, and the first distance is smaller than the second distance.

[0015] In some embodiments, on the projection plane, the normal projection of the explosion-proof valve covers the center of the normal projection outer contour of the cover plate body.

[0016] In some embodiments, on the projection plane, the center of the normal projection of the explosion-proof valve is arranged apart from the center of the normal projection outer contour of the cover plate body.

[0017] In some embodiments, on the projection plane, the minimum distance between the normal projection outer contour of the explosion-proof valve and the normal projection outer contour of the cover plate body is in the range of 3mm-10mm.

[0018] In some embodiments, on the projection plane, the distance between any two points on the normal projection outer contour of the explosion-proof valve is a radial distance, and the maximum radial distance of the explosion-proof valve is in the range of 6mm-30mm.

[0019] In some embodiments, the explosion-proof valve comprises an explosion-proof valve body and a protective sheet, the cover plate body comprises a first surface and a second surface arranged oppositely along the thickness direction thereof, the cover plate body is provided with a through hole penetrating through the first surface and the second surface, the explosion-proof valve body covers the opening of the through hole towards the first surface, and the protective sheet covers the opening of the through hole towards the second surface.

[0020] In some embodiments, the explosion-proof valve body is provided with a thinned area, and the thickness of the thinned area is 0.15mm-0.7mm.

[0021] In some embodiments, the protective sheet is fixedly bonded to the second surface.

[0022] In some embodiments, the thickness of the protective sheet is 0.2mm-0.7mm.

[0023] In some embodiments, on the projection surface, the minimum distance between the outer projection contour of the pole assembly and the outer projection contour of the explosion-proof valve is 5mm-15mm; and / or, the minimum distance between the outer projection contour of the pole assembly and the outer projection contour of the cover plate body is 3mm-10mm.

[0024] In some embodiments, the cover plate body comprises a first surface and a second surface arranged oppositely along the thickness direction thereof, the cover plate body is provided with a first communication hole penetrating through the first surface and the second surface, and the pole assembly is arranged in the first communication hole, the pole assembly comprising: a first pole connected to the second surface; and a second pole comprising a connecting cylinder and a connecting plate, the connecting plate being connected to the first surface, the connecting cylinder penetrating through the first communication hole to connect the first pole and the connecting plate, the connecting plate being adapted to be electrically connected to the pole core, the first pole being provided with a relief hole opening towards the connecting cylinder, and the connecting cylinder being connected to the first pole through the relief hole.

[0025] In some embodiments, the relief hole comprises a first hole section close to the second surface and a second hole section away from the second surface, the first hole section and the second hole section being in communication, the aperture of the first hole section being smaller than the aperture of the second hole section to define a stepped surface, the connecting cylinder comprising a cylinder portion and a limiting portion connected to the cylinder portion, the limiting portion being arranged on one side of the cylinder portion in the axial direction, the limiting portion being placed on the stepped surface and fixedly connected to the first pole.

[0026] In some embodiments, the connecting cylinder and the connecting plate are an integral piece or separate pieces.

[0027] In some embodiments, the pole post assembly further comprises a pole post cover plate connected with the first pole post to cover the escape hole.

[0028] In some embodiments, the cover plate assembly further comprises an insulating seal disposed between the pole post assembly and the cover plate body.

[0029] A battery cell according to an embodiment of the present application comprises: a shell, an accommodating cavity with an opening formed in the shell; a pole core, the pole core being disposed in the accommodating cavity; a cover plate assembly, the cover plate assembly being the aforementioned cover plate assembly, the cover plate assembly being disposed at the opening.

[0030] A battery cell according to an embodiment of the present application, by employing the aforementioned cover plate assembly, the use safety of the battery cell is improved.

[0031] In some embodiments, the battery cell further comprises a current collecting plate, the current collecting plate being disposed in the accommodating cavity and between the cover plate assembly and the pole core, the pole post assembly being electrically connected with the pole core through the current collecting plate.

[0032] In some embodiments, the current collecting plate is provided with a connecting protrusion protruding towards the pole post assembly, the pole post assembly being connected with the connecting protrusion.

[0033] In some embodiments, the battery cell is formed as a cylindrical battery, the pole core has a center hole in the middle part; in the thickness direction of the cover plate body, at least part of the explosion-proof valve is disposed opposite to the center hole.

[0034] In some embodiments, the battery cell is formed as a cylindrical battery, the pole core has a center hole in the middle part; in the thickness direction of the cover plate body, the explosion-proof valve is disposed opposite to part of the center hole.

[0035] A battery pack according to an embodiment of the present application comprises a plurality of the aforementioned battery cells.

[0036] A battery pack according to an embodiment of the present application, by employing the aforementioned battery cell, the use safety of the battery pack is improved.

[0037] An electric device according to an embodiment of the present application comprises the aforementioned battery cell or the aforementioned battery pack.

[0038] An electric device according to an embodiment of the present application, by employing the aforementioned battery cell or battery pack, the use safety of the electric device is improved, and the use cost of the electric device is reduced.

[0039] Additional aspects and advantages of the present application will become apparent from the following description, or will be learned by practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0040] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description, taken in conjunction with the following drawings in which:

[0041] Fig. 1 is a top view of a cover plate assembly according to some embodiments of the first aspect of the present application.

[0042] Fig. 2 is an exploded view of the cover plate assembly of Fig. 1 in cooperation with a current collector plate.

[0043] Fig. 3 is a cross-sectional view of the cover plate assembly of Fig. 1 in cooperation with a current collector plate.

[0044] Fig. 4 is a close-up view of region I in Fig. 3.

[0045] Fig. 5 is a top view of a cover plate assembly according to some embodiments of the second aspect of the present application.

[0046] Fig. 6 is a top view of a cover plate assembly according to some embodiments of the third aspect of the present application.

[0047] Fig. 7 is a top view of a cover plate assembly according to some embodiments of the fourth aspect of the present application.

[0048] Fig. 8 is an exploded view of the cover plate assembly of Fig. 7 in cooperation with a current collector plate.

[0049] Fig. 9 is a schematic view of a second pole according to some embodiments of the fifth aspect of the present application.

[0050] Fig. 10 is a cross-sectional view of the cover plate assembly of Fig. 7 in cooperation with a current collector plate.

[0051] Fig. 11 is a schematic view of the current collector plate of Fig. 2.

[0052] Fig. 12 is a schematic view of the current collector plate of Fig. 8.

[0053] Reference Signs: 1000, cover plate assembly; 100, cover plate body; 110, through hole; 120, first communication hole; 130, first surface; 140, second surface; 200, pole assembly; 210, first pole; 211, avoidance hole; 212, step surface; 220, second pole; 221, connecting cylinder; 2211, cylinder portion; 2212, limiting portion; 222, connecting plate; 230, pole cover plate; 300, explosion-proof valve; 320, explosion-proof valve body; 310, thinning region; 400, protective sheet; 500, insulating seal; 510, insulating member; 511, insulating portion; 512, sealing portion; 520, seal; 2000, current collector plate; 2010, connecting protrusion; 2020, second communication hole. DETAILED DESCRIPTION

[0054] Embodiments of the present application are described below in detail with reference to the accompanying drawings, wherein the same or similar components or components having the same or similar functions are denoted by the same or similar reference numerals throughout. The embodiments described below by reference to the accompanying drawings are exemplary and are for the purpose of explaining the present application only, and are not to be understood as limiting the present application.

[0055] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or component referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0056] It should be noted that the conventional battery, being a sodium battery or a large-capacity battery, when a short circuit occurs inside the battery, the electrolyte will quickly vaporize under the action of high temperature of the short circuit, and then a large amount of gas will be generated. In order to improve the safety of the battery in use, a pressure relief valve is usually provided on the battery, and when a large amount of gas is generated in the battery, the pressure relief valve breaks to discharge the gas and improve the safety of the battery in use.

[0057] However, the area of the existing pressure relief valve is too small, and the too small pressure relief valve cannot meet the timely discharge of the internal pressure of the battery, and there is a safety problem of explosion of the battery.

[0058] In the prior art, in order to solve the above problem, a double pressure relief valve is usually provided, but the structure of the double pressure relief valve has a high cost.

[0059] Therefore, the present application provides a cover plate assembly 1000 of a battery monomer.

[0060] The cover plate assembly 1000 of the battery monomer of the embodiments of the present application is described below with reference to the accompanying drawings.

[0061] As shown in FIGS. 1 and 2, the cover plate assembly 1000 of a battery monomer according to the embodiments of the present application comprises a cover plate body 100, a pole assembly 200 and a pressure relief valve 300.

[0062] Wherein, as shown in FIG. 1, FIG. 2 and FIG. 3, the pole post assembly 200 and the explosion-proof valve 300 are both arranged on the cover plate body 100, and the pole post assembly 200 is adapted to be electrically connected with the pole core. Here, it is referred to that the battery monomer has a pole core, and the pole post assembly 200 arranged on the cover plate body 100 is used to be electrically connected with the pole core, so as to facilitate the current of the pole core to be led out by using the pole post assembly 200, to ensure the working performance of the pole core.

[0063] Meanwhile, by arranging the pole post assembly 200 and the explosion-proof valve 300 on the cover plate body 100, the cover plate body 100 can also be used to support the pole post assembly 200 and the explosion-proof valve 300, to improve the position stability of the pole post assembly 200 and the explosion-proof valve 300, so as to ensure the working performance of the pole post assembly 200 and the explosion-proof valve 300.

[0064] Wherein, the explosion-proof valve 300 is mainly used to be broken when a large amount of gas is generated in the battery monomer, so that the gas in the battery monomer can pass through the explosion-proof valve 300, to avoid the safety problem that the battery monomer cannot be discharged in time due to the internal pressure, and to improve the use safety of the battery.

[0065] On the same projection plane, the orthogonal projection area of the explosion-proof valve 300 is S1, and the orthogonal projection area of the cover plate assembly 1000 is S, wherein S1 = 0.2S ~ 0.8S, the units of S and S1 are the same, and the projection plane is perpendicular to the thickness direction of the cover plate body 100. Wherein, the thickness direction here can be understood as the X direction shown in FIG. 3, and the orthogonal projection of the explosion-proof valve 300 and the cover plate assembly 1000 in the thickness direction perpendicular to the cover plate body 100 can also be understood as the orthogonal projection of the explosion-proof valve 300 and the cover plate assembly 1000 in the plane parallel to the cover plate body 100, and the cover plate body 100 shown in FIG. 1 is the plane of the cover plate body 100.

[0066] That is to say, the orthogonal projection area S1 of the explosion-proof valve 300 in the plane parallel to the cover plate body 100 is 0.2 ~ 0.8 times of the orthogonal projection area S of the cover plate assembly 1000 in the plane parallel to the cover plate body 100, wherein when S1 < 0.2S, the area of the explosion-proof valve 300 itself will be reduced, which reduces the exhaust performance of the explosion-proof valve 300, and thus reduces the use safety of the battery monomer to a certain extent; when S1 > 0.8S, the explosion-proof valve 300 will occupy a larger area on the cover plate body 100, and since the pole post assembly 200 also needs to be arranged on the cover plate body 100, the space for arranging the pole post assembly 200 on the cover plate body 100 will be smaller, which affects the size and installation of the pole post assembly 200.

[0067] Therefore, the present application sets the normal projection area S1 of the explosion-proof valve 300 in the direction perpendicular to the thickness direction of the cover plate body 100 as 0.2-0.8 times of the normal projection area S of the cover plate assembly 1000 in the direction perpendicular to the thickness direction of the cover plate body 100, so that the gas production during the instantaneous gasification of the electrolyte can be smoothly discharged through the explosion-proof valve 300, while avoiding the occupation of more space on the cover plate body 100 by the explosion-proof valve 300, which is conducive to ensuring the size of the pole assembly 200.

[0068] It should be noted that the same unit of S and S1 means that when the unit of the normal projection area S1 of the explosion-proof valve 300 in the direction perpendicular to the thickness direction of the cover plate body 100 is square centimeters, the unit of the normal projection area S of the cover plate assembly 1000 in the direction perpendicular to the thickness direction of the cover plate body 100 is also square centimeters; when the unit of the normal projection area S1 of the explosion-proof valve 300 in the direction perpendicular to the thickness direction of the cover plate body 100 is square meters, the unit of the normal projection area S of the cover plate assembly 1000 in the direction perpendicular to the thickness direction of the cover plate body 100 is also square meters.

[0069] That is, the present application preferably designs the explosion-proof valve 300 which affects the safety performance of the battery monomer, ensures the area of the explosion-proof valve 300, and realizes the improvement of the pressure relief capacity of the explosion-proof valve 300, so as to ensure the working performance of the battery monomer to a certain extent.

[0070] In summary, the present application provides a cover plate assembly 1000 which is different from the current industry technology, and the main technical solution is to design a large-size specification explosion-proof valve 300 on the cover plate body 100, instead of the structure of double-direction double explosion-proof valves used in the existing sodium material system or large-capacity type battery, so as to simplify the structure of the cover plate body 100, realize directional and effective explosion-proof, and improve the safety performance of the battery monomer.

[0071] From the above structure, it can be known that the cover plate assembly 1000 of the battery monomer of the embodiment of the present application creatively sets the size relationship between the normal projection area S1 of the explosion-proof valve 300 in the direction perpendicular to the thickness direction of the cover plate body 100 and the normal projection area S of the cover plate assembly 1000 in the direction perpendicular to the thickness direction of the cover plate body 100, so as to realize the setting of the large-size specification explosion-proof valve 300 on the cover plate assembly 1000, and improve the use safety of the battery monomer.

[0072] It can be understood that, compared with the design of the double-direction double explosion-proof valve in the prior art to improve the use safety of the battery, the cover plate assembly 1000 of the battery monomer of the present application can simplify the structure of the cover plate assembly 1000 while realizing the improvement of the use safety of the battery monomer, reduce the manufacturing cost of the cover plate assembly 1000, and be conducive to improving the manufacturing efficiency of the cover plate assembly 1000.

[0073] It should be noted that the shape of the explosion-proof valve 300 is circular in FIG. 2, and in other embodiments, the shape of the explosion-proof valve 300 can be designed as any geometric shape such as a rectangle, a triangle, a trapezoid, a ring, or a sector according to actual process or performance requirements, and the present application does not make specific limitations.

[0074] In some embodiments, S1 = 0.2S ~ 0.5S. To achieve further optimization of the coverage area of the explosion-proof valve 300 on the cover plate body 100, while ensuring that the gas production amount when the electrolyte is instantaneously gasified can be smoothly discharged through the explosion-proof valve 300, the explosion-proof valve 300 can also avoid occupying more space on the cover plate body 100, which is conducive to ensuring the size of the pole assembly 200.

[0075] In specific examples, S1 = 0.2S, 0.3S, 0.4S, 0.5S, 0.6S, 0.7S, or 0.8S, etc.

[0076] In some embodiments, in combination with FIGS. 1, 2, and 3, on the projection plane, the orthographic projection of the pole assembly 200 deviates from the center of the orthographic projection outer contour of the cover plate body 100, and the orthographic projection of the pole assembly 200 is close to one side of the center of the orthographic projection outer contour of the cover plate body 100, and the orthographic projection of the explosion-proof valve 300 is close to the one side. That is, the orthographic projection of the pole assembly 200 on the plane parallel to the cover plate body 100 is arranged to deviate from the center of the orthographic projection outer contour of the cover plate body 100 on the plane parallel to the cover plate body 100, and the projection of the explosion-proof valve 300 on the plane parallel to the cover plate body 100 is located on the side of the orthographic projection of the pole assembly 200 close to the center of the orthographic projection outer contour of the cover plate body 100.

[0077] The above can also be understood as, in the radial direction of the cover plate body 100, the pole assembly 200 is arranged to deviate from the radial center of the cover plate body 100, the explosion-proof valve 300 and the pole assembly 200 are arranged in sequence in the radial direction of the cover plate body 100, and the explosion-proof valve 300 is located on the side of the pole assembly 200 close to the radial center of the cover plate body 100.

[0078] It should be noted that the orthographic projection of the pole assembly 200 deviating from the center of the orthographic projection outer contour of the cover plate body 100 can be understood as that the center of the orthographic projection of the pole assembly 200 and the center of the orthographic projection outer contour of the cover plate body 100 are arranged to be spaced apart on the projection plane; the radial direction of the cover plate body 100 is perpendicular to the axial direction of the cover plate body 100, and the axial direction of the cover plate body 100 can be understood as the X direction shown in FIG. 3.

[0079] Further, when the shape of the orthographic projection of the pole post assembly 200 and the outer contour of the orthographic projection of the cover plate body 100 is circular, the center is the center of the circle of the orthographic projection of the pole post assembly 200 and the outer contour of the orthographic projection of the cover plate body 100; when the shape of the orthographic projection of the pole post assembly 200 and the outer contour of the orthographic projection of the cover plate body 100 is square, the center is the intersection of the diagonal lines of the orthographic projection of the pole post assembly 200 and the outer contour of the orthographic projection of the cover plate body 100; when the shape of the orthographic projection of the pole post assembly 200 and the outer contour of the orthographic projection of the cover plate body 100 is triangular, the center is the intersection of the three medians of the orthographic projection of the pole post assembly 200 and the outer contour of the orthographic projection of the cover plate body 100.

[0080] Through the above arrangement, the pole post assembly 200 can leave a central area of the cover plate body 100 in the radial direction, so that the cover plate body 100 has sufficient space on one side of the pole post assembly 200 in the radial direction of the cover plate body 100. When the explosion-proof valve 300 is arranged on the side of the pole post assembly 200 close to the center of the cover plate body 100 in the radial direction of the cover plate body 100, sufficient space is ensured on the cover plate body 100 for arranging the explosion-proof valve 300, thereby facilitating the arrangement of a large-size specification explosion-proof valve 300 on the cover plate body 100, and enabling the orthographic projection area S1 of the explosion-proof valve 300 in the plane parallel to the cover plate body 100 to be effectively formed to be 0.2-0.8 times the orthographic projection area S of the cover plate assembly 1000 in the plane parallel to the cover plate body 100, thereby improving the pressure relief capacity of the explosion-proof valve 300 and ensuring the smoothness of the exhaust to some extent, thereby improving the safety of the battery monomer.

[0081] That is, the focus of the present application is the structural design of the cover plate assembly 1000, which ensures that the pole post assembly 200 and the explosion-proof valve 300 can be arranged on the cover plate body 100, and preferably designs the explosion-proof valve 300 affecting the safety performance of the battery monomer, thereby improving the pressure relief capacity of the explosion-proof valve 300 and to some extent ensuring the working performance of the battery monomer.

[0082] In summary, the present application provides a cover plate assembly 1000 different from the current industry technology, and the main technical solution is to design the pole post assembly 200 to be offset relative to the radial center of the cover plate body 100, thereby leaving the radial center area of the cover plate body 100, which is conducive to designing a large-size specification explosion-proof valve 300 on the cover plate body 100, replacing the existing sodium material system or large-capacity battery with a two-way double explosion-proof valve structure, simplifying the structure of the cover plate body 100, realizing directional and effective explosion prevention, and improving the safety performance of the battery monomer.

[0083] In some embodiments, the minimum distance between the orthographic projection outer contour of the explosion-proof valve 300 and the center of the orthographic projection outer contour of the cover plate body 100 is a first distance, and the minimum distance between the orthographic projection outer contour of the pole assembly 200 and the center of the orthographic projection outer contour of the cover plate body 100 is a second distance, and the first distance is smaller than the second distance. That is, the minimum distance between the orthographic projection outer contour of the explosion-proof valve 300 and the center of the orthographic projection outer contour of the cover plate body 100 is smaller than the minimum distance between the orthographic projection outer contour of the pole assembly 200 and the center of the orthographic projection outer contour of the cover plate body 100, so that the explosion-proof valve 300 can be arranged closer to the radial center of the cover plate body 100 in the radial direction of the cover plate body 100, thereby facilitating the arrangement of a large-size explosion-proof valve 300 on the cover plate body 100, improving the pressure relief capacity of the explosion-proof valve 300, and improving the use safety of the battery monomer.

[0084] It should be noted that the minimum distance between the orthographic projection outer contour of the explosion-proof valve 300 and the center of the orthographic projection outer contour of the cover plate body 100 refers to that there are multiple distances between the orthographic projection outer contour of the explosion-proof valve 300 and the center of the orthographic projection outer contour of the cover plate body 100 in the projection plane, and the closest distance between the orthographic projection outer contour of the explosion-proof valve 300 and the center of the orthographic projection outer contour of the cover plate body 100 is defined as the minimum distance between the orthographic projection outer contour of the explosion-proof valve 300 and the center of the orthographic projection outer contour of the cover plate body 100.

[0085] Correspondingly, the minimum distance between the orthographic projection outer contour of the pole assembly 200 and the center of the orthographic projection outer contour of the cover plate body 100 refers to that there are multiple distances between the orthographic projection outer contour of the pole assembly 200 and the center of the orthographic projection outer contour of the cover plate body 100 in the projection plane, and the closest distance between the orthographic projection outer contour of the pole assembly 200 and the center of the orthographic projection outer contour of the cover plate body 100 is defined as the minimum distance between the orthographic projection outer contour of the pole assembly 200 and the center of the orthographic projection outer contour of the cover plate body 100.

[0086] In the description of the present application, the features defined as “first” and “second” can include one or more of the features explicitly or implicitly, for distinguishing the described features, without order or importance.

[0087] In some embodiments, as shown in FIGS. 1, 2 and 3, the center of the normal projection of the explosion-proof valve 300 is spaced apart from the center of the normal projection of the cover plate body 100 on the projection plane. In this way, the explosion-proof valve 300 can be arranged closer to the center of the cover plate body 100 in the radial direction of the cover plate body 100, which is conducive to arranging a large-size explosion-proof valve 300 on the cover plate body 100, thereby improving the pressure relief capacity of the explosion-proof valve 300.

[0088] In some embodiments, as shown in FIGS. 1, 2 and 3, the center of the normal projection of the explosion-proof valve 300 is spaced apart from the center of the normal projection of the cover plate body 100 on the projection plane. In this way, the explosion-proof valve 300 can be arranged closer to the center of the cover plate body 100 in the radial direction of the cover plate body 100, which is conducive to arranging a large-size explosion-proof valve 300 on the cover plate body 100, thereby improving the pressure relief capacity of the explosion-proof valve 300.

[0089] That is, in the radial direction of the cover plate body 100, the explosion-proof valve 300 and the pole post assembly 200 on the cover plate assembly 1000 of the present application are arranged away from the radial center of the cover plate body 100, so as to reasonably utilize the space on the cover plate body 100, and to arrange a large-size explosion-proof valve 300 while ensuring that the explosion-proof valve 300 and the pole post assembly 200 can be arranged on the cover plate body 100, thereby improving the pressure relief capacity of the explosion-proof valve 300 and the use safety of the battery cell.

[0090] In some embodiments, as shown in FIGS. 1, 2 and 3, the outer contour of the explosion-proof valve 300 is spaced apart from the outer edge of the cover plate body 100 in the radial direction of the cover plate body 100. It should be noted that, since the explosion-proof valve 300 needs to be arranged on the cover plate body 100 through the mounting hole (e.g., the through hole 110 described below), spacing the outer contour of the explosion-proof valve 300 from the outer edge of the cover plate body 100 can space the mounting hole from the outer edge of the cover plate body 100, thereby avoiding damage to the cover plate body 100 to some extent during the process of opening the mounting hole, prolonging the service life of the cover plate body 100, and improving the structural strength of the cover plate body 100.

[0091] In some embodiments, the minimum distance between the outer contour of the explosion-proof valve 300 and the outer contour of the cover plate body 100 in the projection plane is in the range of 3mm to 10mm. Here, it can also be understood that, in the plane parallel to the cover plate body 100, there are multiple distances between the outer contour of the explosion-proof valve 300 and the outer contour of the cover plate body 100, and the minimum distance is in the range of 3mm to 10mm. It can also be understood that, in the plane parallel to the cover plate body 100, the minimum distance between the outer contour of the through hole 110 and the outer contour of the cover plate body 100 is in the range of 3mm to 10mm.

[0092] Therefore, the minimum distance between the outer contour of the explosion-proof valve 300 and the outer contour of the cover plate body 100 in the projection plane can be understood as L1 shown in FIG. 1. When L1 is kept in a suitable range, the structural strength of the cover plate body 100 can be ensured, and the explosion-proof valve 300 occupies a suitable space on the cover plate body 100, and there is enough space on the cover plate body 100 to arrange the pole assembly 200, so as to ensure the size and installation of the pole assembly 200.

[0093] Therefore, the minimum distance between the outer contour of the explosion-proof valve 300 and the outer contour of the cover plate body 100 in the projection plane can be understood as L1 shown in FIG. 1. When L1 is kept in a suitable range, the structural strength of the cover plate body 100 can be ensured, and the explosion-proof valve 300 occupies a suitable space on the cover plate body 100, and there is enough space on the cover plate body 100 to arrange the pole assembly 200, so as to ensure the size and installation of the pole assembly 200.

[0094] In specific examples, the minimum distance between the outer contour of the explosion-proof valve 300 and the outer contour of the cover plate body 100 in the projection plane is 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm, etc.

[0095] In some embodiments, the distance between any two points on the outer contour of the explosion-proof valve 300 in the projection plane is a radial distance, and the maximum radial distance of the explosion-proof valve 300 is in the range of 6mm to 30mm. Here, it means that, in the projection plane, when the explosion-proof valve 300 has multiple radial distances, the maximum radial distance is in the range of 6mm to 30mm, so that the size of the explosion-proof valve 300 is in the range of 6mm to 30mm.

[0096] When the maximum radial distance of the explosion-proof valve 300 is designed in the above range, on the one hand, the area of the explosion-proof valve 300 is appropriate, and the exhaust performance of the explosion-proof valve 300 is improved, thereby improving the use safety of the battery monomer; at the same time, the area occupied by the explosion-proof valve 300 is appropriate, and there is enough space on the cover plate body 100 to arrange the pole column assembly 200, so as to ensure the size and installation of the pole column assembly 200.

[0097] Therefore, the value range of the maximum radial distance of the explosion-proof valve 300 is set to 6mm-30mm, so that the gas production when the electrolyte is instantaneously gasified can be smoothly discharged through the explosion-proof valve 300, and at the same time, the explosion-proof valve 300 occupies appropriate space on the cover plate body 100, which is beneficial to ensure the size of the pole column assembly 200, improve the working performance of the pole column assembly 200, and reduce the installation difficulty of the pole column assembly 200.

[0098] In specific examples, the maximum radial distance of the explosion-proof valve 300 is 6mm, 10mm, 15mm, 20mm, 25mm or 30mm, etc.

[0099] It should be noted that the maximum radial distance of the explosion-proof valve 300 can be understood as L2 shown in FIG. 1.

[0100] When the explosion-proof valve 300 is formed in a circular shape, the maximum radial distance of the explosion-proof valve 300 can also be understood as the diameter of the explosion-proof valve 300.

[0101] Of course, in other embodiments, the maximum radial distance of the explosion-proof valve 300 can also be adjusted according to the material system of the battery monomer, the diameter of the pole core, the capacity of the battery monomer or the weight of the electrolyte of the battery monomer, and is not limited to be set to the above 6mm-30mm.

[0102] In some embodiments, as shown in FIGS. 2 and 3, the explosion-proof valve 300 includes an explosion-proof valve body 320 and a protective sheet 400, the cover plate body 100 includes a first surface 130 and a second surface 140, the first surface 130 and the second surface 140 are oppositely arranged along the thickness direction of the cover plate body 100, the cover plate body 100 is provided with a through hole 110 penetrating through the first surface 130 and the second surface 140, the explosion-proof valve body 320 covers the opening of the through hole 110 towards the first surface 130, and the protective sheet 400 covers the opening of the through hole 110 towards the second surface 140. Wherein, the thickness direction of the cover plate body 100 can be understood as the X direction shown in FIG. 3, that is, the axial direction of the cover plate body 100.

[0103] That is, the cover plate body 100 includes a first surface 130 and a second surface 140 arranged opposite in the axial direction of the cover plate body 100, and the cover plate body 100 is further provided with a through hole 110 penetrating the first surface 130 and the second surface 140, so that the through hole 110 penetrates the cover plate body 100 in the axial direction of the cover plate body 100. After the through hole 110 is formed, the through hole 110 has an opening towards the first surface 130 and an opening towards the second surface 140. By covering the opening of the through hole 110 towards the first surface 130 with the explosion-proof valve body 320 and covering the opening of the through hole 110 towards the second surface 140 with the protective sheet 400, the through hole 110 can be covered with the explosion-proof valve 300. Not only can the use safety of the battery monomer be improved by using the explosion-proof valve 300, but also the external foreign matter can be prevented from entering the battery monomer through the through hole 110, thereby ensuring the working performance of the battery monomer to a certain extent.

[0104] In some embodiments, as shown in FIGS. 2 and 3, the explosion-proof valve body 320 is arranged at the opening of the through hole 110 towards the first surface 130, so as to arrange the explosion-proof valve body 320 on the cover plate body 100, thereby facilitating the use of the cover plate body 100 to support the explosion-proof valve body 320, improving the positional stability of the explosion-proof valve body 320, and reducing the matching difficulty of the explosion-proof valve body 320 and the cover plate body 100.

[0105] Optionally, the explosion-proof valve body 320 is connected to the opening of the through hole 110 towards the first surface 130 by laser welding fusion, so as to not only reduce the matching difficulty of the explosion-proof valve body 320 and the cover plate body 100, but also ensure the connection strength of the explosion-proof valve body 320 and the cover plate body 100, improve the positional stability of the explosion-proof valve body 320, and thereby ensure the working performance of the explosion-proof valve body 320.

[0106] It should be noted that after the explosion-proof valve body 320 is laser welded, it needs to ensure that there is no virtual welding or welding hole, and has the design required airtightness.

[0107] In some embodiments, as shown in FIGS. 2 and 3, the protective sheet 400 is arranged at the opening of the through hole 110 towards the second surface 140, so as to arrange the protective sheet 400 on the cover plate body 100 and arrange the explosion-proof valve body 320 and the protective sheet 400 at opposite ends of the through hole 110, thereby facilitating the use of the protective sheet 400 to protect the explosion-proof valve body 320, avoiding the damage of the explosion-proof valve body 320 caused by the falling of external foreign matters to the explosion-proof valve body 320, thereby ensuring the working performance of the explosion-proof valve body 320 and ensuring that the explosion-proof valve body 320 can effectively realize the rapid exhaust and pressure relief of the battery monomer, thereby playing a role in explosion prevention and to a certain extent solving the technical problem of the self-explosion of the battery monomer.

[0108] Optionally, the protective sheet 400 is made of rubber to ensure that the protective sheet 400 can be dissolved after being heated, so as to ensure that the protective sheet 400 can be dissolved when the explosion-proof valve body 320 is heated to the point of exhaust, so as to facilitate the exhaust of the gas through the through hole 110, and ensure the safety of the battery monomer.

[0109] In some embodiments, as shown in FIGS. 1 and 2, the explosion-proof valve body 320 is provided with a thinning area 310, and the thickness of the thinning area 310 is 0.15mm-0.7mm. This is to ensure that when the internal pressure of the battery monomer is large, the explosion-proof valve body 320 can be effectively broken, so as to facilitate the exhaust of the gas in the battery monomer through the explosion-proof valve 300, to improve the effect of pressure relief and explosion-proof, and ensure the working performance of the explosion-proof valve 300.

[0110] In some embodiments, a thinning notch structure can be provided on the explosion-proof valve body 320 to form the thinning area 310 on the explosion-proof valve body 320, thereby ensuring the working performance of the explosion-proof valve 300.

[0111] The shape of the thinning area 310 can be any geometric shape such as a circle, a ring, or a geometric intersection.

[0112] It should be noted that the thickness of the thinning area 310 as described above can be understood as the thickness of the part of the structure of the explosion-proof valve body 320 after being thinned. When the thickness of the thinning area 310 is thin, the structural strength of the explosion-proof valve body 320 will be reduced, and the service life of the explosion-proof valve body 320 will be shortened. When the thickness of the thinning area 310 is thick, when the internal pressure of the battery monomer is large, the explosion-proof valve body 320 cannot be effectively broken, and the safety of the battery monomer is reduced.

[0113] Therefore, the thickness of the thinning area 310 is set to 0.15mm-0.7mm, so that the structural strength of the explosion-proof valve body 320 is ensured, and when the internal pressure of the battery monomer is large, the explosion-proof valve body 320 can be effectively broken, so as to facilitate the exhaust of the gas in the battery monomer through the explosion-proof valve 300, to achieve the effect of pressure relief and explosion-proof, and to improve the safety of the battery monomer.

[0114] In specific examples, the thickness of the thinning area 310 is 0.15mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, or 0.7mm, etc.

[0115] Of course, in other embodiments, the thickness of the thinning area 310 can also be determined according to the explosion-proof pressure designed for each type of battery monomer.

[0116] In some embodiments, the protective sheet 400 is fixedly attached to the second surface 140. In this way, the protective sheet 400 is fixedly connected to the cover plate body 100, and at the same time, when thermal runaway gas is discharged, the connection between the protective sheet 400 and the cover plate body 100 is dissolved by heat, facilitating the discharge of gas, and further ensuring the safety of the battery cell.

[0117] In some embodiments, the thickness of the protective sheet 400 is in the range of 0.2mm to 0.7mm. Here, the thickness of the protective sheet 400 can be understood as T shown in FIG. 3. When the thickness of the protective sheet 400 is designed to be in the above range, the working performance of the protective sheet 400 is further improved, so that the protective sheet 400 effectively protects the explosion-proof valve body 320, and the protective sheet 400 is dissolved when heated, thereby improving the exhaust effect.

[0118] Therefore, the thickness of the protective sheet 400 is set to be in the range of 0.2mm to 0.7mm, so that the working performance of the protective sheet 400 is ensured, and the protective sheet 400 can be dissolved after being heated, facilitating the discharge of gas.

[0119] In specific examples, the thickness of the protective sheet 400 is 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm or 0.7mm, etc.

[0120] In some embodiments, in combination with FIGS. 1, 2 and 3, the pole assembly 200 is spaced apart from the outer edge of the cover plate body 100 and the explosion-proof valve 300 in the radial direction of the cover plate body 100. Since the pole assembly 200 is arranged on the cover plate body 100 through the mounting hole (the first communication hole 120 below), by spacing the pole assembly 200 from the outer edge of the cover plate body 100 and the explosion-proof valve 300 in the radial direction of the cover plate body 100, the first communication hole 120 can be spaced apart from the outer edge of the cover plate body 100, thereby to some extent avoiding damage to the cover plate body 100 during the process of opening the first communication hole 120, prolonging the service life of the cover plate body 100, and at the same time, improving the structural strength of the cover plate body 100, and avoiding damage to the explosion-proof valve 300 during assembly of the pole assembly 200, to ensure the working performance of the explosion-proof valve 300.

[0121] That is, by spacing the pole assembly 200 from the outer edge of the cover plate body 100 and the explosion-proof valve 300 in the radial direction of the cover plate body 100, the structural strength of the cover plate body 100 is ensured, and at the same time, the working performance of the explosion-proof valve 300 is ensured.

[0122] In some embodiments, the minimum distance between the outer contour of the positive projection of the pole post assembly 200 and the outer contour of the positive projection of the explosion-proof valve 300 on the projection plane is in the range of 5mm to 15mm. Here, it is meant that on the plane parallel to the cover plate body 100, there are multiple distances between the outer contour of the positive projection of the pole post assembly 200 and the outer contour of the positive projection of the explosion-proof valve 300, and the minimum distance is in the range of 5mm to 15mm. It can also be understood that on the plane parallel to the cover plate body 100, the minimum distance between the outer contour of the positive projection of the first communication hole 120 and the outer contour of the positive projection of the through hole 110 is in the range of 5mm to 15mm.

[0123] Therefore, the minimum distance between the outer contour of the positive projection of the pole post assembly 200 and the outer contour of the positive projection of the explosion-proof valve 300 on the projection plane can be understood as L3 shown in FIG. 1. When L3 is designed to be of an appropriate size, it is convenient for the assembly of the pole post assembly 200 and the explosion-proof valve 300, and further improves the working performance of the pole post assembly 200 and the explosion-proof valve 300, which is beneficial for setting a large size of the explosion-proof valve 300, and on the other hand, it is also convenient for setting an appropriate distance between the pole post assembly 200 and the outer edge of the cover plate body 100, and ensuring the structural strength of the cover plate body 100.

[0124] Therefore, the minimum distance between the outer contour of the positive projection of the pole post assembly 200 and the outer contour of the positive projection of the explosion-proof valve 300 on the projection plane can be understood as L3 shown in FIG. 1. When L3 is designed to be of an appropriate size, it is convenient for the assembly of the pole post assembly 200 and the explosion-proof valve 300, and further improves the working performance of the pole post assembly 200 and the explosion-proof valve 300, which is beneficial for setting a large size of the explosion-proof valve 300, and on the other hand, it is also convenient for setting an appropriate distance between the pole post assembly 200 and the outer edge of the cover plate body 100, and ensuring the structural strength of the cover plate body 100.

[0125] In specific examples, the minimum distance between the outer contour of the positive projection of the pole post assembly 200 and the outer contour of the positive projection of the explosion-proof valve 300 on the projection plane is 5mm, 8mm, 10mm, 12mm or 15mm, etc.

[0126] Alternatively, the minimum distance between the outer contour of the positive projection of the pole post assembly 200 and the outer contour of the positive projection of the cover plate body 100 on the projection plane is in the range of 3mm to 10mm. Here, it is meant that on the plane parallel to the cover plate body 100, there are multiple distances between the outer contour of the positive projection of the pole post assembly 200 and the outer contour of the positive projection of the cover plate body 100, and the minimum distance is in the range of 3mm to 10mm. It can also be understood that on the plane parallel to the cover plate body 100, the minimum distance between the outer contour of the positive projection of the first communication hole 120 and the outer contour of the positive projection of the cover plate body 100 is in the range of 3mm to 10mm.

[0127] Therefore, the minimum distance between the outer contour of the orthogonal projection of the pole assembly 200 and the outer contour of the orthogonal projection of the cover plate body 100 on the projection plane can be understood as L4 shown in FIG. 1. When L4 is designed to be of a proper size, the distance between the first communication hole 120 and the outer edge of the cover plate body 100 is proper, the structural strength of the cover plate body 100 is improved, and the pole assembly 200 occupies a proper space on the cover plate body 100, so that there is enough space on the cover plate body 100 to arrange the explosion-proof valve 300 and other structural members, which is beneficial to arranging the explosion-proof valve 300 of a large size specification and improving the use safety of the battery monomer.

[0128] Therefore, the minimum distance between the outer contour of the orthogonal projection of the pole assembly 200 and the outer contour of the orthogonal projection of the cover plate body 100 on the projection plane can be understood as L4 shown in FIG. 1. When L4 is designed to be of a proper size, the distance between the first communication hole 120 and the outer edge of the cover plate body 100 is proper, the structural strength of the cover plate body 100 is improved, and the pole assembly 200 occupies a proper space on the cover plate body 100, so that there is enough space on the cover plate body 100 to arrange the explosion-proof valve 300 and other structural members, which is beneficial to arranging the explosion-proof valve 300 of a large size specification and improving the use safety of the battery monomer.

[0129] In specific examples, the minimum distance between the outer contour of the orthogonal projection of the pole assembly 200 and the outer contour of the orthogonal projection of the cover plate body 100 on the projection plane is 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm, etc.

[0130] In some embodiments, in combination with FIGS. 1, 5, 6, and 7, the outer shape of the pole assembly 200 can be any closed geometric shape such as a ring, a rectangle, a sector, an arc, or a circle, and the present application does not make specific limitations.

[0131] In some embodiments, as shown in FIGS. 2 and 3, the cover plate body 100 includes a first surface 130 and a second surface 140, which are oppositely arranged along the thickness direction of the cover plate body 100, and the cover plate body 100 is provided with a first communication hole 120 penetrating the first surface 130 and the second surface 140, and the pole column assembly 200 is arranged in the first communication hole 120. Here, it is referred to that the cover plate body 100 includes the first surface 130 and the second surface 140 oppositely arranged along the axial direction of the cover plate body 100, and the cover plate body 100 is further provided with the first communication hole 120 penetrating the first surface 130 and the second surface 140, so that the first communication hole 120 penetrates the cover plate body 100 along the axial direction of the cover plate body 100. By arranging the pole column assembly 200 in the first communication hole 120, the pole column assembly 200 can be arranged on the cover plate body 100, so as to facilitate supporting the pole column assembly 200 by the cover plate body 100, improve the position stability of the pole column assembly 200, and reduce the difficulty of cooperation between the pole column assembly 200 and the cover plate body 100.

[0132] In some embodiments, as shown in FIGS. 3 and 4, the pole column assembly 200 includes a first pole column 210 and a second pole column 220, the first pole column 210 is connected with the second surface 140, the second pole column 220 includes a connecting cylinder 221 and a connecting plate 222, the connecting plate 222 is connected with the first surface 130, the connecting cylinder 221 penetrates the first communication hole 120 to connect the first pole column 210 and the connecting plate 222, and the connecting plate 222 is adapted to be electrically connected with the pole core. The first pole column 210 is provided with a avoiding hole 211 opening towards the connecting cylinder 221, and the connecting cylinder 221 is connected with the first pole column 210 through the avoiding hole 211. Here, it is referred to that the connecting plates 222 of the first pole column 210 and the second pole column 220 are arranged on opposite sides of the cover plate body 100 respectively. Since the first pole column 210 is provided with the avoiding hole 211 opening towards the connecting cylinder 221, the connecting cylinder 221 of the second pole column 220 can effectively penetrate the first communication hole 120 of the cover plate body 100 and the avoiding hole 211 of the first pole column 210 to connect the first pole column 210 and the connecting plate 222, so as to realize the electrical connection between the first pole column 210 and the connecting plate 222. When the connecting plate 222 is electrically connected with the pole core, the current of the pole core can be led out by the first pole column 210, so as to ensure the working performance of the pole core and reduce the difficulty of electrical connection between the pole core and external structural members.

[0133] It can also be understood that the second pole column 220 is arranged as the connecting cylinder 221 and the connecting plate 222, the connecting plate 222 is mainly used for electrical connection with the pole core, and the connecting cylinder 221 is used for fixedly connecting the second pole column 220 with the first pole column 210, so as to realize the fixed connection between the pole core and the first pole column 210, and facilitate leading out the current of the pole core by the first pole column 210, so as to ensure the working performance of the pole core.

[0134] In some embodiments, the connecting barrel 221 is formed as a hollow piece to facilitate the electrical connection between the connecting plate 222 and the pole core, and to reduce the difficulty of connecting the connecting plate 222 and the pole core, thereby reducing the difficulty of connecting the pole assembly 200 and the pole core.

[0135] In a specific example, because the connecting barrel 221 is formed as a hollow piece, during the connection between the pole assembly 200 and the pole core, the connecting tool can pass through the connecting barrel 221 and act on the connecting plate 222, thereby facilitating the electrical connection between the connecting plate 222 and the pole core.

[0136] In addition, by providing the avoiding hole 211 on the first pole 210 to communicate with the connecting barrel 221, the connecting barrel 221 can pass through the first pole 210, so that the connecting barrel 221 can be connected with the first pole 210, thereby reducing the difficulty of connecting the connecting barrel 221 and the first pole 210.

[0137] It is also worth noting that, compared with the prior art, the pole assembly 200 is composed of the first pole 210 and the second pole 220, which can reduce the assembly difficulty of the pole assembly 200 and the cover plate body 100, facilitate the assembly of the pole assembly 200, and effectively arrange the pole assembly 200 on opposite sides of the cover plate body 100. In addition, the first pole 210 can be processed separately, which can ensure that the first pole 210 has a large enough welding surface and a flatness, and during the assembly of the first pole 210 and the second pole 220, the first pole 210 and the second pole 220 can be used to squeeze the insulating sealing member 500 (the specific structure of the insulating sealing member 500 can be seen from FIG. 4) arranged between the pole assembly 200 and the cover plate body 100, to ensure the sealing effect of the insulating sealing member 500.

[0138] In some embodiments, as shown in FIG. 4, the avoiding hole 211 includes a first hole section close to the second surface 140 and a second hole section away from the second surface 140, the first hole section and the second hole section are communicated, the hole diameter of the first hole section is smaller than the hole diameter of the second hole section to define a step surface 212, the connecting barrel 221 includes a barrel portion 2211 and a limiting portion 2212, the limiting portion 2212 is connected with the barrel portion 2211, the limiting portion 2212 is arranged on one side of the barrel portion 2211 in the axial direction, the limiting portion 2212 is placed on the step surface 212 and fixedly connected with the first pole 210. In this way, while achieving the fixed connection between the connecting barrel 221 and the first pole 210, the difficulty of connecting the connecting barrel 221 and the first pole 210 is reduced, and the connection strength between the connecting barrel 221 and the first pole 210 is ensured, so that the first pole 210 and the second pole 220 are fixedly connected.

[0139] It should be noted that by setting the hole diameter of the first hole section to be smaller than the hole diameter of the second hole section, a recessed groove is provided on the inner circumferential wall of the first pole post 210 to form a stepped surface 212, thereby facilitating the fixed connection of the first pole post 210 and the second pole post 220.

[0140] In some embodiments, the limiting portion 2212 of the connecting cylinder 221 is riveted with the first pole post 210 to ensure the connection strength of the connecting cylinder 221 and the first pole post 210, and meanwhile, it is also convenient to compress the insulation sealing member 500 by using the connecting cylinder 221 and the first pole post 210, thereby further ensuring the sealing effect of the insulation sealing member 500.

[0141] In some embodiments, as shown in FIGS. 2 and 8, the connecting cylinder 221 and the connecting plate 222 are an integral piece or separate pieces. That is, the connecting cylinder 221 and the connecting plate 222 can be processed by an integral molding process, or the connecting cylinder 221 and the connecting plate 222 can be separately processed, and then the connecting cylinder 221 and the connecting plate 222 are assembled and connected after the processing of the connecting cylinder 221 and the connecting plate 222 is completed, to form the second pole post 220.

[0142] In some embodiments, as shown in FIG. 2, the cold heading forming process can be used to process the second pole post 220, so that the connecting cylinder 221 and the connecting plate 222 are formed as an integral piece, thereby eliminating the connection between the connecting cylinder 221 and the connecting plate 222, reducing the processing difficulty of the second pole post 220, and improving the forming efficiency of the second pole post 220.

[0143] In other embodiments, as shown in FIGS. 8, 9 and 10, the connecting cylinder 221 and the connecting plate 222 are separate pieces, and the connecting cylinder 221 and the connecting plate 222 can be processed by a stamping forming process, and then the connecting cylinder 221 and the connecting plate 222 are welded to form the second pole post 220 after the stamping is completed. Since the production cost of the stamping forming process is low, the above-mentioned arrangement can effectively reduce the manufacturing cost of the second pole post 220.

[0144] Alternatively, the connecting cylinder 221 and the connecting plate 222 are assembled into the second pole post 220 by continuous laser penetration welding, to ensure the connection strength of the connecting cylinder 221 and the connecting plate 222.

[0145] In some embodiments, as shown in FIGS. 2, 3 and 4, the pole post assembly 200 further includes a pole post cover plate 230 connected with the first pole post 210 to cover the escape hole 211. In this way, while avoiding the falling of external foreign matters into the escape hole 211, the pole post assembly 200 can also be electrically connected with external structural members (such as busbars) by using the pole post cover plate 230, thereby facilitating the electrical connection between multiple battery monomers.

[0146] In a specific example, during the assembly of the battery monomer, the connecting plate 222 is first connected with the pole core through the connecting cylinder 221, and after the connection is completed, the pole post cover plate 230 is connected with the first pole post 210 to cover the avoiding hole 211 and increase the connection area of the pole post assembly 200 and the external structure, thereby ensuring the stability of the connection.

[0147] Optionally, the pole post cover plate 230 is welded with the first pole post 210 to increase the connection strength of the pole post cover plate 230 and the first pole post 210, so that the relative position of the pole post cover plate 230 and the first pole post 210 is stable.

[0148] Of course, in other embodiments, if the size of the first pole post 210 meets the welding surface requirement of the assembly of the plurality of battery monomers, the pole post cover plate 230 can also not be arranged to simplify the structure of the pole post assembly 200 and reduce the manufacturing difficulty and manufacturing cost of the pole post assembly 200.

[0149] In some embodiments, as shown in FIGS. 4 and 10, the cover plate assembly 1000 further comprises an insulation sealing piece 500 arranged between the pole post assembly 200 and the cover plate body 100, so that the pole post assembly 200 and the cover plate body 100 form an insulation sealing fit, thereby avoiding the electrical connection between the pole post assembly 200 and the cover plate body 100 to ensure the working performance of the battery monomer.

[0150] In some embodiments, when the first pole post 210 and the second pole post 220 are connected, the insulation sealing piece 500 can be compressed, thereby forming the insulation and sealing of the pole post assembly 200 and the cover plate body 100 and ensuring the sealing effect of the insulation sealing piece 500.

[0151] Optionally, as shown in FIGS. 2, 3 and 4, the insulation sealing piece 500 comprises an insulation piece 510 and a sealing piece 520 arranged on opposite sides of the cover plate body 100, so as to arrange the insulation sealing piece 500 between the pole post assembly 200 and the cover plate body 100, thereby realizing the insulation sealing fit of the cover plate body 100 and the pole post assembly 200 and reducing the installation difficulty of the insulation sealing piece 500 and the cover plate body 100.

[0152] In some embodiments, as shown in FIGS. 2, 3 and 4, the insulating member 510 is arranged on the outer side of the cover plate body 100, and the sealing member 520 is arranged on the inner side of the cover plate body 100. The insulating member 510 is made of high-performance thermoplastic resin, such as polyphenylene sulfide, to ensure the insulation performance of the insulating member 510, so that the cover plate body 100 and the pole assembly 200 can effectively form an insulation interval. The sealing member 520 is made of fluororubber, ethylene-propylene-diene rubber or meltable polytetrafluoroethylene, so that the sealing member 520 has insulation performance and sealing performance, provides sealing function for the pole assembly 200, and avoids the electrolyte in the battery monomer from overflowing, to ensure the working performance of the battery monomer.

[0153] In some embodiments, as shown in FIGS. 8 and 10, the insulating member 510 includes an insulating part 511 and a sealing part 512. The sealing part 512 is arranged opposite to the sealing member 520, and the insulating part 511 is arranged on the outer periphery of the sealing part 512, so that the insulating member 510 has insulation and sealing effects. In this way, while ensuring the insulation cooperation of the cover plate body 100 and the pole assembly 200, the electrolyte in the battery monomer can be further prevented from overflowing, to ensure the working performance of the battery monomer.

[0154] In some embodiments, as shown in FIGS. 4 and 10, the insulating sealing member 500 is clamped between the first pole 210 and the connecting plate 222. In this way, while achieving the insulation and sealing cooperation of the pole assembly 200 and the cover plate body 100, the assembly difficulty of the insulating sealing member 500 is reduced, and the first pole 210 and the second pole 220 are used to press the insulating sealing member 500, to improve the sealing effect of the insulating sealing member 500.

[0155] A battery monomer according to an embodiment of the present application is described below.

[0156] As shown in FIGS. 2 and 8, a battery monomer according to an embodiment of the present application includes a shell, a pole core and a cover plate assembly 1000.

[0157] The shell has an accommodating cavity with an opening, and the pole core is arranged in the accommodating cavity. In this way, the pole core is arranged in the shell, the pole core is protected by the shell, the service life of the pole core is prolonged, and the use safety of the pole core is improved.

[0158] As shown in FIGS. 2, 3 and 4, the cover plate assembly 1000 is the aforementioned cover plate assembly 1000, and the specific structure of the cover plate assembly 1000 is not described herein again. The cover plate assembly 1000 is arranged at the opening. In this way, while achieving the plugging of the opening of the shell by the cover plate assembly 1000, the cover plate assembly 1000 can be arranged opposite to the pole core, so that the pole assembly 200 of the cover plate assembly 1000 can be electrically connected to the pole core, to ensure the working performance of the pole core.

[0159] Meanwhile, since the aforementioned cover plate assembly 1000 can be provided with a large size specification explosion-proof valve 300, the battery monomer of the embodiment of the present application can effectively improve the use safety of the battery monomer by adopting the aforementioned cover plate assembly 1000.

[0160] In some embodiments, the shell is formed by stamping or welding, and the shell is made of aluminum or steel.

[0161] In some embodiments, the current collector 2000 is arranged in the accommodating cavity and between the cover plate assembly 1000 and the pole core, and the pole assembly 200 is electrically connected to the pole core through the current collector 2000. Thus, the pole core and the pole assembly 200 are electrically connected, and the connection difficulty of the pole core and the pole assembly 200 is reduced.

[0162] In some embodiments, the current collector 2000 is welded to the pole core and the pole assembly 200, respectively. Thus, the pole core and the pole assembly 200 can be electrically connected, the connection strength of the pole core and the pole assembly 200 is ensured, the connection difficulty of the pole core and the pole assembly 200 is reduced, the assembly efficiency of the battery monomer is improved, and the structural stability is improved.

[0163] In some embodiments, as shown in FIGS. 2, 3 and 4, the current collector 2000 is provided with a connecting protrusion 2010 protruding towards the pole assembly 200, and the pole assembly 200 is connected to the connecting protrusion 2010. Thus, the pole assembly 200 and the current collector 2000 are connected, and the connection difficulty of the pole assembly 200 and the current collector 2000 is reduced. Thus, the electrical connection difficulty of the pole assembly 200 and the pole core is reduced, and the working performance of the pole core is ensured.

[0164] Meanwhile, the connecting protrusion 2010 protruding towards the pole assembly 200 is arranged on the current collector 2000. On the one hand, a buffer is formed during the connection of the current collector 2000 and the pole assembly 200. Thus, the contact area of the current collector 2000 and the pole assembly 200 is ensured, the connection strength is improved, and the forming process of the lead-out sheet is omitted. Thus, the manufacturing process of the current collector 2000 is simplified, the manufacturing cost of the current collector 2000 is reduced, the manufacturing cost of the battery monomer is reduced, the pole core is not damaged during the connection of the pole assembly 200 and the current collector 2000, and the performance of the pole core is ensured.

[0165] In some embodiments, the connecting plate 222 of the pole assembly 200 and the connecting protrusion 2010 of the current collector 2000 are penetrated and welded. Thus, the pole assembly 200 and the current collector 2000 are connected, the connection strength of the pole assembly 200 and the current collector 2000 is ensured, and the connection difficulty of the pole assembly 200 and the current collector 2000 is reduced.

[0166] In a specific example, when the pole assembly 200 and the current collector 2000 need to be connected, the position of the connecting protrusion 2010 of the current collector 2000 can be first identified by a CCD (Charge Coupled Device) camera, then the angle of the cover plate assembly 1000 can be corrected, the connecting plate 222 of the pole assembly 200 is corresponded and assembled with the connecting protrusion 2010 of the current collector 2000, the close contact between the connecting plate 222 and the connecting protrusion 2010 is ensured, finally the welding tool is passed through the connecting cylinder 221 to act on the connecting plate 222, so as to facilitate the penetration welding between the connecting plate 222 and the connecting protrusion 2010, and the connection quality is ensured.

[0167] In addition, since the welding surface of the current collector 2000 of the application is the connecting protrusion 2010 formed directly on the current collector 2000, the current carrying capacity of the current collector can be ensured, and the performance requirements of high rate charge and discharge can be realized.

[0168] In some embodiments, as shown in FIGS. 2 and 11, the connecting protrusion 2010 is a bridge formed on the current collector 2000, so that the connecting protrusion 2010 can protrude towards the pole assembly 200, and at the same time, the connecting protrusion 2010 can also play a buffering role to ensure the contact area between the current collector 2000 and the pole assembly 200 and improve the connection strength.

[0169] Of course, in other embodiments, as shown in FIGS. 8 and 12, the local structure of the current collector 2000 can also be stamped to form the connecting protrusion 2010.

[0170] In some embodiments, the battery cell is formed as a cylindrical battery, and the center part of the pole core has a center hole; at least part of the explosion-proof valve 300 is arranged opposite to the center hole in the thickness direction of the cover plate body 100. Since the center hole of the pole core has a certain size, after the battery cell is injected with electrolyte, part of the electrolyte will remain in the center hole of the pole core. When the battery cell occurs thermal runaway, the thermal decomposition of the electrolyte in the center hole will release a large amount of gas. By arranging at least part of the explosion-proof valve 300 opposite to the center hole, it can ensure that a large amount of gas in the center hole can be quickly discharged, so that the gas in the battery cell can be quickly discharged, and the use safety of the battery cell is improved.

[0171] In some embodiments, the battery cell is formed as a cylindrical battery, the middle part of the pole core has a center hole; the explosion-proof valve 300 is arranged opposite to part of the center hole in the thickness direction of the cover plate body 100. Here, it is referred to that, in the thickness direction of the cover plate body 100, not the whole structure of the center hole is opposite to the explosion-proof valve 300, but part of the structure of the center hole is opposite to the explosion-proof valve 300, so that the explosion-proof valve 300 can be arranged offset to the center of the cover plate body 100, while avoiding that the explosion-proof valve 300 occupies too much space on the cover plate body 100, and also can make the pole column assembly 200 and the explosion-proof valve 300 have a certain distance, and ensure that a large amount of gas in the center hole can be quickly discharged.

[0172] Optionally, as shown in FIGS. 2, 3 and 10, the current collecting disc 2000 is provided with a second communication hole 2020 opposite to the center hole, so as to realize the communication between the center hole and the explosion-proof valve 300, to a certain extent, avoid that the current collecting disc 2000 hinders the discharge of the gas in the center hole, so as to ensure that a large amount of gas in the center hole can be effectively discharged through the explosion-proof valve 300 quickly, and improve the use safety of the battery cell.

[0173] The battery pack of the embodiment of the application is described below.

[0174] The battery pack of the embodiment of the application is described below.

[0175] The battery cell is the aforementioned battery cell, and the specific structure of the battery cell is not described herein.

[0176] It should be noted that, since the aforementioned battery cell is provided with the cover plate assembly 1000, the battery pack of the embodiment of the application can effectively improve the use safety of the battery pack by using the aforementioned battery cell.

[0177] In the description of the application, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0178] The power consuming device of the embodiment of the application is described below.

[0179] The power consuming device of the embodiment of the application is described below.

[0180] The battery cell is the aforementioned battery cell, and the specific structure of the battery cell is not described herein, and the battery pack is the aforementioned battery pack, and the specific structure of the battery pack is not described herein.

[0181] It should be noted that, since the aforementioned battery cell or battery pack is provided with the cover plate assembly 1000, the power consuming device of the embodiment of the application can effectively improve the use safety of the power consuming device by using the aforementioned battery cell or battery pack.

[0182] It should be further noted that the electric device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, an electric vehicle, an electric automobile, a ship, a spacecraft, etc.

[0183] The electric toy can include a fixed or mobile electric toy, such as a game console, an electric automobile toy, an electric ship toy, an electric aircraft toy, etc.; the spacecraft can include an airplane, a rocket, a space shuttle, a spacecraft, etc.; the electric tool can include a metal cutting electric tool, a grinding electric tool, an assembling electric tool, and a railway electric tool, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, and an electric planer, etc.

[0184] In the description of the present application, it should be noted that unless explicitly defined and limited, the terms "mounting", "connecting" should be understood in a broad sense, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, or electrically connected. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0185] Other configurations of the battery cell cover plate assembly 1000, the battery cell, the battery pack, and the electric device according to the embodiments of the present application are known to those skilled in the art, and will not be described in detail here.

[0186] In the description of the present application, the description referring to the terms "embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0187] Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A cover plate assembly (1000) of a battery cell, characterized by, The cover plate body (100) comprises: The pole assembly (200) and the explosion-proof valve (300) are arranged on the cover plate body (100), and the pole assembly (200) is adapted to be electrically connected with a pole core. On the same projection plane, the area of the front projection of the explosion-proof valve (300) is S1, and the area of the front projection of the cover plate assembly (1000) is S, wherein S1=0.2S~0.8S, S and S1 have the same unit, and the projection plane is perpendicular to the thickness direction of the cover plate body (100). S1=0.2S~0.5S.

2. The battery cell cover plate assembly (1000) according to claim 1, characterized in that, On the projection plane, the front projection of the pole assembly (200) deviates from the center of the front projection outline of the cover plate body (100), and the side of the front projection of the pole assembly (200) close to the center of the front projection outline of the cover plate body (100) is a first side, and the front projection of the explosion-proof valve (300) is arranged close to the first side.

3. The battery cell cover plate assembly (1000) of claim 1, wherein, On the projection plane, the minimum distance between the front projection outline of the explosion-proof valve (300) and the center of the front projection outline of the cover plate body (100) is a first distance, the minimum distance between the front projection outline of the pole assembly (200) and the center of the front projection outline of the cover plate body (100) is a second distance, and the first distance is smaller than the second distance.

4. The battery cell cover plate assembly (1000) according to claim 3, characterized in that, On the projection plane, the front projection of the explosion-proof valve (300) covers the center of the front projection outline of the cover plate body (100).

5. The battery cell cover plate assembly (1000) of claim 3, wherein, On the projection plane, the center of the front projection of the explosion-proof valve (300) is arranged apart from the center of the front projection outline of the cover plate body (100).

6. The battery cell cover plate assembly (1000) of claim 3, wherein, On the projection plane, the minimum distance between the front projection outline of the explosion-proof valve (300) and the front projection outline of the cover plate body (100) is 3mm~10mm.

7. The battery cell cover plate assembly (1000) of claim 3, wherein, On the projection plane, the distance between any two points on the front projection outline of the explosion-proof valve (300) is a radial distance, and the maximum radial distance of the explosion-proof valve (300) is 6mm~30mm.

8. The battery cell cover plate assembly (1000) of claim 3, wherein, The explosion-proof valve (300) comprises an explosion-proof valve body (320) and a protective sheet (400), the cover plate body (100) comprises a first surface (130) and a second surface (140) arranged opposite along the thickness direction thereof, the cover plate body (100) is provided with a through hole (110) penetrating through the first surface (130) and the second surface (140), the explosion-proof valve body (320) covers the opening of the through hole (110) facing the first surface (130), and the protective sheet (400) covers the opening of the through hole (110) facing the second surface (140).

9. The battery cell cover plate assembly (1000) of claim 1, wherein, The explosion-proof valve body (320) is provided with a thinned area (310), and the thickness of the thinned area (310) is 0.15mm~0.7mm.

10. The battery cell cover plate assembly (1000) of claim 9, wherein, The protective sheet (400) is adhesively fixed to the second surface (140).

11. The battery cell cover plate assembly (1000) of claim 9, wherein, The thickness of the protective sheet (400) is 0.2mm~0.7mm.

12. The battery cell cover plate assembly (1000) of claim 9, wherein, ​ 13. The battery cell cover plate assembly (1000) of claim 3, wherein, On the projection plane, the minimum distance between the outer contour of the orthogonal projection of the pole column assembly (200) and the outer contour of the orthogonal projection of the explosion-proof valve (300) is in the range of 5mm-15mm; and / or, On the projection plane, the minimum distance between the outer contour of the orthogonal projection of the pole column assembly (200) and the outer contour of the orthogonal projection of the cover plate body (100) is in the range of 3mm-10mm.

14. The battery cell cover plate assembly (1000) according to any one of claims 1-13, characterized in that, The cover plate body (100) comprises a first surface (130) and a second surface (140) oppositely arranged along the thickness direction thereof, and a first communication hole (120) penetrating through the first surface (130) and the second surface (140) is arranged on the cover plate body (100), and the pole column assembly (200) is arranged in the first communication hole (120). The first pole column (210) is connected with the second surface (140); The second pole column (220) comprises a connecting cylinder (221) and a connecting plate (222), the connecting plate (222) is connected with the first surface (130), the connecting cylinder (221) penetrates through the first communication hole (120) to connect the first pole column (210) and the connecting plate (222), the connecting plate (222) is adapted to be electrically connected with the pole core, and the first pole column (210) is provided with a avoiding hole (211) opening towards the connecting cylinder (221), and the connecting cylinder (221) is connected with the first pole column (210) through the avoiding hole (211).

15. The battery cell cover plate assembly (1000) of claim 14, wherein, The avoiding hole (211) comprises a first hole section close to the second surface (140) and a second hole section away from the second surface (140), the first hole section and the second hole section are communicated, the aperture of the first hole section is smaller than the aperture of the second hole section to define a step surface (212), the connecting cylinder (221) comprises a cylinder portion (2211) and a limiting portion (2212) connected with the cylinder portion (2211), the limiting portion (2212) is arranged on one side of the cylinder portion (2211) in the axial direction, and the limiting portion (2212) is placed on the step surface (212) and fixedly connected with the first pole column (210).

16. The battery cell cover plate assembly (1000) of claim 14, wherein, The connecting cylinder (221) and the connecting plate (222) are an integral part or separate parts.

17. The battery cell cover plate assembly (1000) of claim 14, wherein, The pole column assembly (200) further comprises a pole column cover plate (230) connected with the first pole column (210) to cover the avoiding hole (211).

18. The battery cell cover plate assembly (1000) of claim 14, wherein, An insulating sealing member (500) is arranged between the pole column assembly (200) and the cover plate body (100).

19. A battery cell, characterized by It comprises: A shell, an accommodating cavity with an opening formed in the shell; A pole core arranged in the accommodating cavity; A cover plate assembly (1000) according to any one of claims 1-17, the cover plate assembly (1000) is arranged at the opening.

20. The battery cell of claim 19, wherein, Further comprising a current collecting plate (2000) arranged in the accommodating cavity and located between the cover plate assembly (1000) and the pole core, the pole post assembly (200) being electrically connected with the pole core through the current collecting plate (2000).

21. The battery cell of claim 20, wherein, The current collecting plate (2000) is provided with a connecting protrusion (2010) protruding towards the pole post assembly (200), and the pole post assembly (200) is connected with the connecting protrusion (2010) in a matching mode.

22. The battery cell of claim 19, wherein, The battery cell is formed as a cylindrical battery, and the pole core has a center hole in the middle part thereof; At least part of the explosion-proof valve (300) is arranged opposite to the center hole in the thickness direction of the cover plate body (100).

23. The battery cell of claim 19, wherein, The battery cell is formed as a cylindrical battery, and the pole core has a center hole in the middle part thereof, and the explosion-proof valve (300) is arranged opposite to part of the center hole in the thickness direction of the cover plate body (100).

24. A battery pack, characterized by The battery pack comprises a plurality of battery cells according to any one of claims 19-23.

25. An electrical device, comprising: The battery pack comprises a battery cell according to any one of claims 19-23 or a battery pack according to claim 24.

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