Top cover assembly, battery monomer, battery and electric device

Abstract

The invention relates to a top cover assembly, a battery monomer, a battery and a power utilization device. The top cover assembly comprises a cover plate which is provided with a first surface, a second surface and a first through hole, the first surface and the second surface are opposite to each other, and the first through hole penetrates through the first surface and the second surface; the pole comprises a first connecting part and at least two second connecting parts, the first connecting part is located on the side, provided with the first surface, of the cover plate, and the second connecting parts are connected with the first connecting part and arranged in the first preset direction; at least part of each second connecting part is arranged in the first through hole in a penetrating manner and is used for being connected with a tab; and the first insulating part comprises a first insulating part arranged between the first connecting part and the cover plate.

Description

Technical Field

[0001] The present application relates to the field of new energy technology, and specifically to a top cover assembly, a battery cell, a battery and an electrical device. Background Art

[0002] Lithium-ion batteries have the advantages of high energy density, long cycle life, high rate performance, good safety and environmental protection, and are important energy products for modern electronic products and power vehicles. Battery cells are an important component of batteries.

[0003] There are two technical solutions for battery cells: with and without adapters. In the technical solution with adapters, the tabs of the battery cell are connected to the poles through adapters, so that the poles serve as the electrode terminals of the battery cells. However, the presence of adapters increases the number of parts and the cost of the battery cells. On the other hand, an additional welding process between the tabs and the adapters is added, which further increases the cost of the battery cells.

[0004] In the technical solution without the adapter, the pole and the tab are directly connected. However, due to the limited space on the cover plate, there are restrictions on the position of the pole, so it is necessary to extend the tab to achieve direct connection between the pole and the tab. Extending the tab greatly increases the risk of the tab being inserted into the battery cell and the tab being torn. Summary of the invention

[0005] Based on this, it is necessary to provide a top cover assembly, a battery cell, a battery and an electrical device that can omit the adapter and avoid lengthening the pole ear in order to solve the above problems.

[0006] In one aspect, the present application provides a top cover assembly, comprising: A cover plate, comprising a first surface, a second surface and a first through hole, wherein the first surface and the second surface are opposite to each other, and the first through hole penetrates the first surface and the second surface; A pole, comprising at least one first connection portion and at least two second connection portions, wherein the first connection portion is located on a side of the cover plate having the first surface, each of the second connection portions is connected to the first connection portion and arranged along the first preset direction; each of the second connection portions is at least partially disposed in the first through hole and is used to be connected to a pole lug respectively; and The first insulating member includes a first insulating portion disposed between the first connecting portion and the cover plate.

[0007] In some embodiments, on a virtual plane perpendicular to the thickness direction of the cover plate, the orthographic projection of the first connecting portion does not overlap with the orthographic projection of the first through hole, and the orthographic projection of the second connecting portion covers the orthographic projection of the first through hole.

[0008] In some embodiments, each of the second connecting portions includes a first area and a second area arranged around the first area, the second area is connected to the first connecting portion, the first area protrudes relative to the second area along the direction from the first surface to the second surface, and forms a connecting sub-portion passing through the first through hole.

[0009] In some embodiments, an end of the connecting sub-portion away from the second area is a welding end, the welding end has a welding surface, and the welding end protrudes from the second surface of the cover plate.

[0010] In some embodiments, the top cover assembly also includes a second insulating member, which is arranged on the second surface of the cover plate, and the welding end is arranged through the second insulating member, and the welding surface protrudes from the side surface of the second insulating member away from the cover plate, or the welding surface is flush with the side surface of the second insulating member away from the cover plate.

[0011] In some embodiments, the welding end protrudes from the second surface by a distance of 0 to 5 mm along the thickness direction of the cover plate.

[0012] In some of the embodiments, the distance between the weld mark on the welding surface and the edge of the welding surface is greater than or equal to 1 mm.

[0013] In some embodiments, the first insulating member further includes a second insulating portion, and at least a portion of the second insulating portion covers the second region.

[0014] In some embodiments, the first insulating portion and the second insulating portion are integrally formed.

[0015] In some embodiments, an end surface of the connecting sub-part connected to the second region has a first groove, and the second insulating part also covers an inner wall of the first groove.

[0016] In some embodiments, the second insulating portion is recessed toward the first groove to form a pit.

[0017] In some embodiments, the top cover assembly further includes a first fixing portion, wherein the first fixing portion is connected to the first surface of the cover plate and presses against a side of the second insulating portion facing away from the cover plate.

[0018] In some embodiments, the first fixing portion extends along a peripheral edge of the second connecting portion.

[0019] In some embodiments, the first fixing portion includes a first arc segment, a straight edge segment, and a second arc segment connected in sequence, and the first arc segment and the second arc segment are both located on the side of the straight edge segment facing the first connecting portion; an escape space is formed between an end of the first arc segment away from the straight edge segment and an end of the second arc segment away from the straight edge segment.

[0020] In some embodiments, the center angle of the first arc segment is greater than 90°; and / or The central angle of the second arc segment is greater than 90°.

[0021] In some embodiments, a distance between an end of the first arc segment away from the straight edge segment and the first connecting portion is greater than or equal to 1.4 mm; and / or A distance between an end of the second arc segment away from the straight edge segment and the first connecting portion is greater than or equal to 1.4 mm.

[0022] In some embodiments, the first fixing portion includes a standing edge sub-portion and a flanged edge sub-portion, the standing edge sub-portion is connected to the first surface of the cover plate, the flanged edge sub-portion is connected to the standing edge sub-portion, and is bent relative to the standing edge sub-portion to a side of the second insulating portion away from the cover plate.

[0023] In some embodiments, an insulating gap is provided between an end of the flange sub-portion facing away from the vertical edge sub-portion and the second region, and a portion of the second insulating portion is filled in the insulating gap.

[0024] In some embodiments, the second insulating portion further covers the flange sub-portion and at least a portion of the vertical edge sub-portion; or The second insulating portion does not cover the upright portion and the flange portion.

[0025] In some embodiments, the orthographic projection of the flange sub-portion on the cover plate along the thickness direction of the cover plate is a first orthographic projection, and the orthographic projection of the second connecting portion on the cover plate along the thickness direction of the cover plate is a second orthographic projection; the first orthographic projection partially overlaps or does not overlap with the second orthographic projection.

[0026] In some embodiments, the pole further includes a plurality of transition portions corresponding one-to-one to each of the second connection portions, and each of the transition portions is connected between the first connection portion and the corresponding second connection portion.

[0027] In some embodiments, each of the transition portions is provided with a second through hole; each of the second connecting portions includes a first region and a second region arranged around the first region, the second region is connected to the first connecting portion, the first region protrudes relative to the second region along a direction from the first surface to the second surface, and forms a connecting sub-portion penetrating the first through hole; The first insulating member further includes a second insulating portion and a third insulating portion, the second insulating portion at least partially covers the second region, the third insulating portion fills the second through hole, and the third insulating portion is connected to the first insulating portion and the second insulating portion.

[0028] In some embodiments, the first insulating portion, the second insulating portion and the third insulating portion are integrally formed.

[0029] In some embodiments, the top cover assembly also includes a sealing ring, which includes a first sealing portion and a second sealing portion, wherein the first sealing portion and the second sealing portion are both sleeved on the connecting sub-portion, the first sealing portion is located between the connecting sub-portion and the inner wall of the first through hole, and the second sealing portion is located between the second area and the first surface of the cover plate.

[0030] In some embodiments, the first surface of the cover plate has a first convex strip arranged around the first through hole, and the second sealing portion is pressed against the first convex strip.

[0031] In some embodiments, the sealing ring further includes a second convex strip, wherein the second convex strip is protrudingly disposed on a side of the second sealing portion facing away from the cover plate and is arranged around the second area.

[0032] In some embodiments, the second protrusion is C-shaped, and an opening of the second protrusion faces the first connecting portion.

[0033] In some embodiments, a second groove is formed on a side of the first connecting portion facing the cover plate, and a portion of the first insulating portion is filled in the second groove.

[0034] In some embodiments, the second groove is at least partially narrowed gradually or in a step-like manner in a direction from the groove bottom to the groove opening.

[0035] In some embodiments, the depth dimension of the second groove is h1, the thickness dimension of the first connecting portion is H1, and h1 and H1 satisfy: h1=(5%-50%)H1.

[0036] In some embodiments, a third groove is formed on a surface of the cover plate facing the first connecting portion, and a portion of the first insulating portion is filled in the third groove.

[0037] In some embodiments, the third groove narrows gradually or in a step-wise manner from the groove bottom to the groove opening.

[0038] In some embodiments, the depth dimension of the third groove is h2, the thickness dimension of the cover plate is H2, and h2 and H2 satisfy: h2=(5%-50%)H2.

[0039] In some embodiments, the first connecting portion has a boss and an annular surface on a side facing away from the cover plate, the annular surface is arranged around the boss, and the boss is protruded relative to the annular surface in a direction facing away from the cover plate; The first insulating member further includes a fourth insulating portion, which is arranged around the first connecting portion and covers a peripheral edge of the first connecting portion; A surface of the fourth insulating portion is flush with the annular surface.

[0040] In some embodiments, the number of the second connection parts is two, and the two second connection parts are respectively located on two sides of the first connection part in the first preset direction; or Each of the second connection parts is located on the same side of the first connection part in the second preset direction, and the first preset direction is perpendicular to the second preset direction.

[0041] On the other hand, the present application provides a battery cell, comprising a housing, a battery cell assembly, and a top cover assembly as described in any of the above embodiments; The shell has a receiving cavity and an opening connected to the receiving cavity, the cover plate is arranged at the opening, the battery cell assembly is arranged in the receiving cavity, and has at least two pole ears on the side facing the cover plate, and each second connecting portion is connected to the corresponding pole ear by passing through the first through hole into the receiving cavity.

[0042] In another aspect, the present application provides a battery cell, comprising: A housing having a receiving cavity and a first wall as a side wall of the receiving cavity, wherein the first wall has an inner side surface, an outer side surface and a first through hole, wherein the inner side surface faces the receiving cavity, the outer side surface faces away from the receiving cavity, and the first through hole passes through the inner side surface and the outer side surface; A battery cell assembly is accommodated in the accommodation cavity of the shell and has at least two tabs on a side facing the first wall; A pole, comprising a first connection portion and at least two second connection portions, wherein the first connection portion is arranged on the outer side of the first wall, each of the second connection portions is connected to the first connection portion and arranged along the width direction of the first wall; each of the second connection portions is at least partially passed through the first through hole and is respectively connected to the corresponding pole lug; and The first insulating member includes a first insulating portion disposed between the first connecting portion and the first wall.

[0043] On the other hand, the present application provides a battery, characterized by comprising a battery cell as described in any of the above embodiments.

[0044] On the other hand, the present application provides an electrical device, including a battery cell as described in any of the above embodiments, or including a battery as described in any of the above embodiments.

[0045] Compared with the prior art, this application has the following beneficial effects: In the above-mentioned top cover assembly, battery cell, battery and electrical device, the pole is directly connected to the pole ears of the two groups of battery cells through the two second connecting parts, which avoids the use of adapters on the one hand, thereby reducing the number of parts of the top cover assembly and reducing one welding process; on the other hand, by arranging the two second connecting parts along the arrangement direction of the two groups of battery cells, the two second connecting parts pass through the cover plate through the first through holes on the cover plate and are respectively connected to the pole ears of the two groups of battery cells, thereby avoiding the need to increase the radial size of the pole and the need to extend the pole ear, thereby avoiding increasing the material cost of the pole ear and increasing the risk of adverse phenomena such as the pole ear being inserted into the battery cell and the pole ear being torn. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 A cross-sectional view of a battery cell at a pole in an embodiment of the present application (the cross section is perpendicular to the length direction of the cover plate); Figure 2 for Figure 1 A schematic structural diagram of a top cover assembly of a battery cell shown; Figure 3 for Figure 2 An exploded structural diagram of the top cover assembly shown; Figure 4 for Figure 2 A cross-sectional view of the top cover assembly shown (the cross section is perpendicular to the length direction of the cover); Figure 5 for Figure 2 A schematic diagram of the structure of the pole of the top cover assembly shown; Figure 6 for Figure 5 The cross-section of the pole shown (the cross section is perpendicular to the length of the cover); Figure 7 for Figure 2 A schematic structural diagram of a sealing ring of a top cover assembly shown; Figure 8 for Figure 2 A schematic structural diagram of a cover plate of a top cover assembly shown; Fig. 9 for Figure 2 A schematic structural diagram of a first insulating member of the top cover assembly shown; Fig.10 This is a cross-sectional view of the top cover assembly at the pole in another embodiment of the present application (the cross section is perpendicular to the length direction of the cover plate). DETAILED DESCRIPTION

[0047] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0048] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0049] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0050] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0051] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0052] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0053] An embodiment of the present application provides an electrical device, a battery and a battery cell, wherein the electrical device includes a battery or a battery cell, and can be provided with electrical energy by the above-mentioned battery or the above-mentioned battery cell. Among them, the above-mentioned electrical device can be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, an energy storage device, an amusement equipment, an elevator and a lifting device, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys or electric airplane toys, etc.; electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers, etc.; energy storage equipment can be energy storage walls, base station energy storage, container energy storage, etc.; amusement equipment can be carousels, jumping machines, etc.

[0054] The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. For new energy vehicles, the above-mentioned battery can be used as a driving power source to replace fossil fuels to provide driving power. This application does not impose any special restrictions on the above-mentioned electrical devices.

[0055] The above-mentioned battery can be a battery pack or a battery module. When the above-mentioned battery is a battery pack, the battery pack specifically includes a battery management system (BMS) and a plurality of the above-mentioned battery cells. The plurality of battery cells can be electrically connected in series, in parallel, or in a combination of series and parallel, and can be communicatively connected with the battery management system, which controls and monitors the working status of each battery cell. In addition, a plurality of battery cells can also first form a battery module with a module management system, and then a plurality of battery modules can be electrically connected in series, in parallel, or in a combination of series and parallel, and together with the battery management system form a battery pack.

[0056] A plurality of battery cells can be installed on supporting structures such as boxes, frames, and brackets. Each battery cell and each battery cell and the battery management system can be electrically connected through an electrical connector, which can be a bus. In addition, each battery cell can also be electrically connected by plugging in its own pole. For example, between two adjacent battery cells, a slot is provided on the pole of one battery cell, and a plug-in is correspondingly provided on the pole of the other battery cell. The plug-in is inserted into the slot to achieve electrical connection. Therefore, for a battery cell, the aforementioned electrical connector can be the pole of another battery cell. Similarly, the battery cell and the battery management system can also be electrically connected by plugging in each other, which will not be elaborated here. The above-mentioned battery cell can be a lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, and its external contour can be a cylinder, a flat body, a rectangular parallelepiped or other shapes, but it is not limited to this. Specifically in the present embodiment, the above-mentioned battery cell is a lithium-ion square battery.

[0057] See also Figure 1 The battery cell 1 includes a shell 200, a battery cell assembly 300 and a top cover assembly 100. The shell 200 is provided with an opening at at least one end, and the shell 200 has a receiving cavity, which is connected to the opening. The battery cell assembly 300 is received in the receiving cavity of the shell 200, and the top cover assembly 100 covers the opening of the shell 200, thereby enclosing the battery cell assembly 300 in the receiving cavity of the shell 200. The battery cell assembly 300 includes at least two groups of battery cells 301 arranged in parallel along the thickness direction of the shell 200, and each group of battery cells 301 extends a pole ear 302 toward the end surface of the top cover assembly 100.

[0058] It should be noted that each group of battery cells 301 can be one battery cell 301 or multiple battery cells 301, which is not limited here. When each group of battery cells 301 includes one battery cell 301, the battery cell 301 extends a positive electrode ear and a negative electrode ear toward the end surface of the top cover assembly 100. When each group of battery cells 301 includes multiple battery cells 301, each battery cell 301 extends a positive electrode ear and a negative electrode ear toward the end surface of the top cover assembly 100, and the positive electrode ears on each battery cell 301 in the same group are close together to form a positive electrode ear, and the negative electrode ears on each battery cell 301 in the same group are close together to form a negative electrode ear.

[0059] As an embodiment, the battery cell assembly 300 includes two groups of battery cells 301, each group of battery cells 301 includes one battery cell 301, that is, the battery cell assembly 300 includes a total of two battery cells 301, and the two battery cells 301 are arranged side by side along the thickness direction of the shell 200, wherein the positive electrode ear on the end surface of one of the battery cells 301 facing the top cover assembly 100 serves as a positive electrode ear, and the negative electrode ear serves as a negative electrode ear; wherein the positive electrode ear on the end surface of the other battery cell 301 facing the top cover assembly 100 serves as another positive electrode ear, and the negative electrode ear serves as another negative electrode ear.

[0060] In the related art, the connection between each positive electrode ear and the positive electrode column on the top cover assembly is achieved through an adapter. However, the existence of the adapter increases the number of parts, increases the cost of the battery cell, increases the resistance inside the battery cell, and reduces the energy efficiency of the battery cell. On the other hand, it adds a welding process between the ear and the adapter, which further increases the cost of the battery cell. In order to overcome the above defects, a technical solution without an adapter has been applied.

[0061] In the technical solution without the adapter, the positive pole on the top cover assembly directly extends into the receiving cavity and is directly connected to the positive ears of each group of battery cells. However, since each group of battery cells is arranged along the thickness direction of the shell, the positive ears of each group of battery cells are also arranged along the thickness direction of the shell. Since the span of each positive ear in the thickness direction of the shell is large, the positive ear needs to be arranged in the middle of the shell in the thickness direction, so the positive pole column of conventional size cannot be directly connected to each positive ear. Therefore, in order to realize that the positive pole column is directly connected to each positive ear, one way is to increase the radial dimension of the pole column so that the pole column is as close to the positive ears on both sides as possible in the thickness direction of the shell to ensure that each positive ear can be directly connected to the positive pole column; another way is to extend the length of the positive ear so that each positive ear extends to the positive pole column and is directly connected to the positive pole column.

[0062] However, the inventors of this application have found in long-term research and development that in the scheme of increasing the radial size of the pole, as the radial size of the pole increases, the material cost of the pole increases, and the size of the mounting hole for mounting the pole is large, resulting in insufficient strength of the cover plate of the top cover assembly. In the scheme of extending the length of the positive ear, the risk of the ear being inserted upside down into the battery cell and the ear being torn will increase. It should be noted that the direct connection between the negative pole and the negative ear also has the above-mentioned defects, which will not be elaborated here.

[0063] In order to overcome the above-mentioned defects, the inventor of the present application creatively proposed a pole that can realize direct connection between the pole and the pole ear. In the technical solution of the present application, the pole is formed by a plate through a stamping process (such as piercing, drawing and cutting, etc.). The pole includes a first connecting portion and at least two second connecting portions connected to the first connecting portion, and the at least two second connecting portions are arranged along a first preset direction, and the first preset direction is consistent with the thickness direction of the shell 200. In other words, the arrangement direction of each second connecting portion is consistent with that of each group of battery cells 301, so that each second connecting portion is opposite to the pole ear 302 of each group of battery cells 301, so that the pole ear 302 of each group of battery cells 301 is directly connected to the corresponding second connecting portion, thereby avoiding the need to increase the radial size of the pole or extend the length of the pole ear 302, thereby overcoming the defects caused by increasing the radial size of the pole and extending the pole ear 302.

[0064] The specific structure of the top cover assembly is described in detail below with reference to the accompanying drawings. Figures 1 to 6 As shown, in the embodiment of the present application, the top cover assembly 100 includes a cover plate 10 and a pole 20. The cover plate 10 has a first surface a1, a second surface a2 and a first through hole 11. The first surface a1 and the second surface a2 are opposite to each other in the thickness direction of the cover plate 10, and the first through hole 11 penetrates the first surface a1 and the second surface a2 of the cover plate 10. The cover plate 10 is covered at the opening of the shell 200 to seal the opening of the shell 200. The first surface a1 of the cover plate 10 is opposite to the battery cell assembly 300 in the receiving cavity of the shell 200, and the second surface a2 of the cover plate 10 faces the battery cell assembly 300 in the receiving cavity of the shell 200. The thickness direction of the above-mentioned shell 200 is consistent with the above-mentioned first preset direction, that is, the two groups of battery cells 301 of the battery cell assembly 300 in the shell 200 are arranged side by side along the first preset direction, so the pole ears 302 of the two groups of battery cells 301 are also arranged at intervals along the first preset direction.

[0065] The pole 20 is arranged on the cover plate 10, and the thickness direction of the pole 20 is consistent with the thickness direction of the cover plate 10. The cover plate 10 may be provided with a positive pole and a negative pole. The positive pole is used to connect with the positive pole ear of each group of battery cells 301, so that the positive pole ear of each group of battery cells 301 is led out of the shell 200; the negative pole is used to connect with the negative pole ear of each group of battery cells 301, so that the negative pole ear of each group of battery cells 301 is led out of the shell 200. The positive pole serves as the positive terminal of the battery cell 1, and the negative pole serves as the negative terminal of the battery cell 1. The positive and negative terminals of each battery cell 1 are connected by electrical connectors to realize the electrical connection of each battery cell 1 in series, parallel, or a mixture of series and parallel.

[0066] It should be noted that, since the structures of the positive pole and the negative pole are similar, for ease of understanding, this article takes one of the poles 20 as an example. That is to say, the "pole" in this article can be a positive pole or a negative pole (except for cases where it is clearly stated), and the "ear" in this article can be a positive ear or a negative ear (except for cases where it is clearly stated), as long as all the ears 302 connected to the positive pole are positive ears, and all the ears 302 connected to the negative pole are negative ears.

[0067] Specifically, the pole 20 includes a first connection portion 21 and two second connection portions 22. The first connection portion 21 is located on the side of the cover plate 10 having the first surface a1, and the two second connection portions 22 are connected to the first connection portion 21. The two second connection portions 22 are arranged along the first preset direction, that is, the arrangement direction of the two second connection portions 22 is consistent with the arrangement direction of the pole tabs 302 of the two groups of battery cells 301. At least part of each second connection portion 22 is penetrated in the first through hole 11 on the cover plate 10, and is used to connect with the corresponding pole tabs 302 respectively, that is, the two second connection portions 22 are connected to the pole tabs 302 of the two groups of battery cells 301 in a one-to-one correspondence.

[0068] In the above-mentioned top cover assembly 100, the pole 20 is directly connected to the pole ears 302 of the two groups of battery cells 301 through the two second connecting parts 22, which on the one hand avoids the use of adapters, thereby reducing the number of parts of the top cover assembly 100 and reducing one welding process; on the other hand, by arranging the two second connecting parts 22 along the arrangement direction of the two groups of battery cells 301, the two second connecting parts 22 pass through the cover plate 10 through the first through holes 11 on the cover plate 10, and are respectively connected to the pole ears 302 of the two groups of battery cells 301, thereby avoiding the need to increase the radial size of the pole 20 and the need to extend the pole ears 302, thereby avoiding increasing the material cost of the pole ears 302 and increasing the risk of adverse phenomena such as the pole ears 302 being inserted into the battery cell and the pole ears 302 being torn.

[0069] It is understandable that the number of the second connection parts 22 is not limited to two, but can also be three or more. The number of the second connection parts 22 is related to the number of battery cell groups. Specifically, the number of battery cell groups is N groups, and the number of the second connection parts 22 is also set to N. The N second connection parts 22 are arranged at intervals along the first preset direction, and are all connected to the first connection part 21. The N second connection parts 22 are respectively penetrated through the first through holes 11 on the cover plate 10 and are connected to the pole ears 302 of each group of battery cells 301 in a one-to-one correspondence, so that the pole ears 302 of the corresponding battery cells 301 are all led out to the first connection part 21. For ease of understanding, this article takes the battery cell assembly 300 including two groups of battery cells 301 and the pole 20 including two second connection parts 22 as an example for explanation.

[0070] It should also be noted that the number of the first connection parts 21 is not limited to one, but may be two or more, and the number of the first connection parts 21 is related to the number of the second connection parts 22. A first connection part 21 is provided between two adjacent second connection parts 22, and the number of the first connection parts 21 is N-1. For example, when the number of the second connection parts 22 is 3 and the number of the first connection parts 21 is 2, the pole 20 includes the second connection part 22, the first connection part 21, the second connection part 22, the first connection part 21, and the second connection part 22 connected in sequence along the first preset direction.

[0071] In one embodiment, a first through hole 11 may be disposed on the cover plate 10 . The first through hole 11 is a hole with a relatively large area and can allow at least two second connection portions 22 to pass through the first through hole 11 .

[0072] It can be understood that, in another embodiment, a first through hole 11 is provided at a position corresponding to each second connection portion 22 on the cover plate 10, so that each second connection portion 22 is respectively penetrated in the first through hole 11 corresponding to each of them, and then respectively connected to the corresponding pole lug 302. In this way, compared with the first through hole 11 in which the pole is integrally mounted on the cover plate 10, in this embodiment, only the first through hole 11 matching the outer contour size of the second connection portion 22 needs to be provided, which greatly reduces the opening area on the cover plate 10, minimizes the adverse effects on the strength of the cover plate 10, and ensures that the strength of the cover plate 10 can meet the requirements.

[0073] See also Figures 4 to 6As shown, in the embodiment of the present application, each second connection portion 22 includes a first area 221 and a second area 222 arranged around the first area 221. The second area 222 is connected to the first connection portion 21. The first area 221 protrudes from the second area 222 along the direction from the first surface a1 to the second surface a2, and forms a connection sub-portion 223 that penetrates the corresponding first through hole 11. In this way, the first area 221 of the second connection portion 22 can be drawn once or multiple times by a stamping process, so that the first area 221 protrudes toward the cover plate 10 relative to the second area 222 to form a connection sub-portion 223. The connection sub-portion 223 extends to the pole ear 302 of the corresponding battery cell group through the corresponding first through hole 11, and is directly connected to the pole ear 302.

[0074] Furthermore, one end of the connecting sub-portion 223 away from the second region 222 is a welding end a3, and the welding end a3 passes through the corresponding first through hole 11 and enters the receiving cavity of the shell 200. In other words, the welding end a3 of the connecting sub-portion 223 protrudes from the second surface a2 of the cover plate 10, thereby avoiding welding the electrode tab 302 and the welding end a3 of the connecting sub-portion 223 inside the first through hole 11, greatly reducing the welding difficulty, and facilitating improving the welding quality of the welding end a3 of the electrode tab 302 and the connecting sub-portion 223.

[0075] Furthermore, the distance that the welding end a3 of the connecting sub-portion 223 protrudes from the second surface a2 of the cover plate 10 along the thickness direction of the cover plate 10 is 0 to 5 mm, thereby avoiding occupying a large space in the receiving cavity due to the welding end a3 protruding too far from the second surface a2, that is, saving space in the receiving cavity of the shell 200, which is beneficial to improving the energy density of the battery.

[0076] Furthermore, the top cover assembly 100 also includes a second insulating member 60, which is arranged on the second surface a2 of the cover plate 10, and is used to form insulation between the cover plate 10 and the battery cell assembly 300. The second insulating member 60 has a third through hole opposite to the first through hole 11, and the connecting sub-portion 223 is penetrated through the corresponding first through hole 11 and the third through hole. The welding end a3 of the connecting sub-portion 223 has a welding surface a4, which protrudes from the side surface of the second insulating member 60 away from the cover plate 10, or the welding surface a4 is flush with the side surface of the second insulating member 60 away from the cover plate 10. In this way, welding of the electrode tab 302 and the welding surface a4 of the connecting sub-portion 223 inside the third through hole is avoided, which greatly reduces the difficulty of welding and is conducive to improving the welding quality of the welding surface a4 of the electrode tab 302 and the connecting sub-portion 223.

[0077] It should be noted that the connection sub-portion 223 and the tab 302 may be welded by a welding process such as laser welding, resistance welding, ultrasonic welding, pressure fusion welding, etc.

[0078] As an embodiment, the tab 302 is welded and fixed to the connecting sub-portion 223 by pressure fusion welding. Specifically, a protrusion 227 is provided on the welding surface a4 of the connecting sub-portion 223. When performing pressure fusion welding, the tab 302 contacts the protrusion 227. Since the flow area at the contact point between the tab 302 and the protrusion 227 is small, the heat generated is large, so that the protrusion 227 melts and the tab 302 is welded and fixed to the welding surface a4 of the connecting sub-portion 223. It can be understood that the shape of the protrusion 227 can be spherical, hemispherical, truncated cone, etc., as long as it can ensure that the protrusion 227 can melt under the action of electrical energy and pressure and weld the tab 302 to the welding surface a4 of the connecting sub-portion 223, it is not limited here.

[0079] As another embodiment method, the tab 302 is welded and fixed to the connecting sub-portion 223 by laser welding. Specifically, the distance between the weld mark on the welding surface a4 of the welding end a3 and the edge of the welding surface a4 is greater than or equal to 1 mm. Optionally, the distance between the weld mark on the welding surface a4 and the edge of the welding surface a4 can be 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm or 2.0 mm, etc., which is not particularly limited here.

[0080] It should be noted that the distance between the weld mark on the weld surface a4 and the edge of the weld surface a4 refers to the distance between any point on the edge of the weld surface a4 and any point on the edge of the weld mark.

[0081] Specifically in the embodiment, the end surface of the connecting sub-portion 223 connected to the second region 222 has a first groove 225, so that the connecting sub-portion 223 has a hollow structure, which is conducive to reducing the weight of the pole 20 and saving the material of the pole 20. It can be understood that in the process of drawing the plate once or multiple times, the first region 221 of the plate is convex to one side relative to the second region 222 as a whole, thereby forming a hollow connecting sub-portion 223.

[0082] Optionally, the depth dimension of the first groove 225 is 1 mm to 5 mm, preferably 1 mm to 3 mm. In this way, if the depth of the first groove 225 is too shallow, the welding end a3 of the connecting sub-part 223 will be far away from the battery cell assembly 300, requiring a longer pole ear 302; if the depth of the first groove 225 is too deep, it will make the drawing process more difficult. In this embodiment, by reasonably designing the depth dimension of the first groove 225, the depth dimension of the first groove 225 is moderate, which can realize the welding of the pole ear 302 and the welding end a3 of the connecting sub-part 223 without lengthening the pole ear 302, and reduce the difficulty of the drawing process, thereby improving the production efficiency and the yield rate of the pole 20.

[0083] It should be noted that the depth dimension of the first groove 225 can be 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm or 5.0 mm, etc., and is not particularly limited herein.

[0084] In the embodiment of the present application, the pole 20 further includes a transition portion 23, and the second region 222 of each second connection portion 22 is connected to the first connection portion 21 through the transition portion 23. The end of the transition portion 23 connected to the second region 222 of the second connection portion 22 is the first end, and the first end at least partially protrudes from the surface of the first connection portion 21 facing the cover plate 10 along the thickness direction of the pole 20. In other words, the transition portion 23 extends obliquely relative to the thickness direction of the pole 20 from the end connected to the first connection portion 21 to the end connected to the second region 222, so that the second connection portion 22 sinks toward the cover plate 10 as a whole relative to the first connection portion 21, thereby making the connection sub-portion 223 closer to the corresponding pole lug 302, which is conducive to reducing the drawing depth of the connection sub-portion 223 as much as possible, reducing the drawing difficulty, and improving the drawing quality of the pole 20.

[0085] Furthermore, the flow area of ​​the transition portion 23 is smaller than the flow area of ​​the first connection portion 21, and smaller than the flow area of ​​the second connection portion 22. In this way, when an abnormality occurs in the circuit during actual use, the temperature at the transition portion 23 rises faster due to the smaller flow area of ​​the transition portion 23, and the transition portion 23 can be quickly fused, thereby cutting off the circuit in time, greatly improving the safety of the battery. It is understandable that the transition portion 23 can reduce the flow area by grooving, opening holes and / or local thinning, ensuring that the circuit can be cut off by fusing in time when the circuit is abnormal.

[0086] In the embodiment of the present application, the top cover assembly 100 further includes a first insulating member 30, and the first insulating member 30 includes a first insulating portion 31. The first insulating portion 31 is disposed between the first connecting portion 21 of the pole 20 and the cover plate 10 and forms insulation, that is, to prevent the first connecting portion 21 of the pole 20 and the cover plate 10 from being electrically conductive.

[0087] Furthermore, the first insulating member 30 also includes a second insulating portion 34, which covers the second area 222 of the pole 20. On the one hand, the second insulating portion 34 insulates and protects the outer surface of the second area 222, and on the other hand, wraps the second area 222 of the pole 20, which is beneficial to increase the overall strength of the pole 20 and reduce the risk of deformation of the pole 20.

[0088] Furthermore, the second insulating part 34 also covers the inner wall of the first groove 225. On the one hand, it provides insulation protection for the inner wall of the first groove 225. On the other hand, it is beneficial to increase the bonding force between the second insulating part 34 and the second connecting part 22, thereby greatly reducing the risk of position displacement or even separation between the second insulating part 34 and the second connecting part 22.

[0089] Furthermore, the second insulating portion 34 is recessed toward the first groove 225 to form a pit 341, that is, the second insulating portion 34 only covers the inner wall of the first groove 225, and does not fill the first groove 225. On the one hand, it is beneficial to improve the bonding force between the second insulating portion 34 and the second connecting portion 22 of the pole 20, and avoid separation or misalignment of the second insulating portion 34 and the second connecting portion 22; on the other hand, it reduces the material usage of the second insulating portion 34 and avoids defects such as uneven injection molding due to local excessive thickness.

[0090] Furthermore, the second insulating portion 34 also extends to each transition portion 23 and covers each transition portion 23, thereby insulating and protecting the surface of the transition portion 23. The first insulating member 30 also includes a fourth insulating portion 35. The fourth insulating portion 35 extends along the peripheral edge of the first connecting portion 21 and covers the peripheral edge of the second insulating portion 34, thereby facilitating the improvement of the overall strength of the pole 20 and insulating and protecting the peripheral edge of the first connecting portion 21. In other words, the side surface of the first connecting portion 21 facing the cover plate 10 is covered by the first insulating portion 31, and the peripheral edge of the first connecting portion 21 is covered by the fourth insulating portion 35. Only the side surface of the first connecting portion 21 facing away from the cover plate 10 is not covered, and the uncovered surface is used for welding with the electrical connector.

[0091] Specifically in the embodiment, the first connection portion 21 has a boss 211 and an annular surface 213 on the side facing away from the cover plate 10, the annular surface 213 is arranged around the boss 211, and the boss 211 is protruded relative to the annular surface 213 in the direction facing away from the cover plate 10. The electrical connector is welded on the boss 211, and the fourth insulating portion 35 of the first insulating member 30 is lower than the annular surface 213 or flush with the annular surface 213. In this way, by providing the boss 211, the injection material can be prevented from flowing onto the surface of the boss 211 during injection molding, causing the first insulating member 30 to cover the surface of the boss 211.

[0092] Optionally, the protrusion height of the boss 211 relative to the annular surface 213 is 0.05 mm to 0.8 mm, preferably 0.1 mm to 0.6 mm or 0.3 mm to 0.5 mm. It should be noted that the protrusion height of the boss 211 relative to the annular surface 213 can be 0.05 mm, 0.20 mm, 0.35 mm, 0.50 mm, 0.65 mm or 0.8 mm, etc., and is not particularly limited here.

[0093] Specifically in the embodiment, at least one second through hole 231 is formed on the transition portion 23, and the first insulating member 30 further includes a third insulating portion 32 filled in the second through hole 231. The third insulating portion 32 is connected to the first insulating portion 31, the second insulating portion 34 and the fourth insulating portion 35, so that the first insulating portion 31, the second insulating portion 34, the third insulating portion 32 and the fourth insulating portion 35 form a whole, which is beneficial to improving the bonding force between the first insulating member 30 and the pole 20 on the one hand, and is beneficial to further improving the overall strength of the pole 20 on the other hand.

[0094] Furthermore, the first insulating part 31, the second insulating part 34, the third insulating part 32 and the third insulating part 32 of the first insulating member 30 are integrally formed, for example, integrally formed by an injection molding process. When the first insulating member 30 is injection-molded, a portion of the molten injection material flows to the surface of each second connecting part 22 and each transition part 23, and forms the second insulating part 34 after solidification; a portion of the molten injection material flows to the surface of the peripheral edge of the first connecting part 21, and forms the fourth insulating part 35 after solidification; a portion of the injection material flows into the second through hole 231, and forms the third insulating part 32 after solidification; a portion of the injection material flows into the space between the first connecting part 21 and the cover plate 10 through the second through hole 231, and forms the first insulating part 31 between the first connecting part 21 and the cover plate 10 after solidification.

[0095] It should be noted that the second through hole 231 on the transition portion 23, on the one hand, plays a role in circulating the injection molding material during injection molding, and on the other hand, also plays a role in reducing the flow area of ​​the transition portion 23, ensuring that the transition portion 23 can be melted in time to cut off the circuit when an abnormality occurs.

[0096] Please also see Figure 7 As shown, specifically in the embodiment, the top cover assembly 100 further includes a first fixing portion 40. The first fixing portion 40 is fixedly connected to the first surface a1 of the cover plate 10, and a portion of the first fixing portion 40 can be bent to a side surface of the second insulating portion 34 away from the cover plate 10 by a rolling process, so that the second insulating portion 34 and the pole 20 are pressed against the cover plate 10 by the first fixing portion 40 to prevent the pole 20 from being separated from the cover plate 10.

[0097] Furthermore, the second insulating portion 34 has a step surface a6 extending along the peripheral edge of the second region 222 of the second connecting portion 22. The first fixing portion 40 extends along the peripheral edge of the second connecting portion 22 and presses against the step surface a6, so that the pressing of the first fixing portion 40 against the second insulating portion 34 is more stable, thereby making the assembly structure of the pole 20 and the cover plate 10 more stable, and preventing the pole 20 from being displaced or even separated from the cover plate 10.

[0098] It should be noted that the number of the first fixing parts 40 is the same as the number of the second connecting parts 22, and the two are arranged in a one-to-one correspondence. Each first fixing part 40 presses against the second insulating part 34 on the surface of the corresponding second connecting part 22, so that each second connecting part 22 of the pole 20 is pressed against the cover plate 10. Optionally, each first fixing part 40 extends along the peripheral edge of the corresponding second connecting part 22 in a C-shape, and the opening of the C-shaped first fixing part 40 faces the first connecting part 21, so that the transition part 23 passes through the opening of the first fixing part 40, avoiding the fourth insulating part 35 covering the peripheral edge of the first connecting part 21 and the second insulating part 34 covering the transition part 23 from interfering with the rolling equipment when the first fixing part 40 is rolled.

[0099] Specifically, the first fixing portion 40 includes a first arc segment 45, a straight edge segment 47, and a second arc segment 49 that are sequentially connected, and the first arc segment 45 and the second arc segment 49 are both located on the side of the straight edge segment 47 facing the first connecting portion 21. An escape space a5 is formed between an end of the first arc segment 45 away from the straight edge segment 47 and an end of the second arc segment 49 away from the straight edge segment 47. It can be understood that the escape space a5 is the space at the opening of the C-shaped first fixing portion 40.

[0100] Optionally, the central angle of the first arc segment 45 is greater than 90°, which is beneficial to extend the length of the first fixing portion 40 so that the first fixing portion 40 can more stably press the second insulating portion 34 and the second connecting portion 22 onto the cover plate 10 .

[0101] Optionally, the central angle of the second arc segment 49 is greater than 90°, which is beneficial to extend the length of the first fixing portion 40 so that the first fixing portion 40 can more stably press the second insulating portion 34 and the second connecting portion 22 onto the cover plate 10 .

[0102] It should be noted that in order to improve the clamping effect, it is necessary to extend the length of the first fixing portion 40 as much as possible. However, extending the length of the first fixing portion 40 will cause the first arc segment 45 and / or the second arc segment 49 to be too close to the end away from the straight edge segment 47 and the first connecting portion 21, thereby causing the fourth insulating portion 35 wrapped around the peripheral edge of the first connecting portion 21 to interfere with the rolling equipment when the first fixing portion 40 is rolled.

[0103] In order to avoid interference between the fourth insulating portion 35 wrapped around the peripheral edge of the first connecting portion 21 and the hemming equipment when the first arc segment 45 is hemmed. In some embodiments, the distance between the end of the first arc segment 45 away from the straight edge segment 47 and the first connecting portion 21 is greater than or equal to 1.4 mm, so that the distance between the end of the first arc segment 45 away from the straight edge segment 47 and the first connecting portion 21 is large enough to ensure that when the first arc segment 45 is hemmed, the fourth insulating portion 35 on the peripheral edge of the first connecting portion 21 will not interfere with the hemming equipment.

[0104] It should be noted that the distance between the end of the first arc segment 45 away from the straight edge segment 47 and the first connecting portion 21 may be 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm or 1.8 mm, etc., which is not particularly limited herein.

[0105] In order to avoid interference between the fourth insulating portion 35 wrapped around the peripheral edge of the first connection portion 21 and the hemming equipment when the second arc segment 49 is hemmed. In some embodiments, the distance between the end of the second arc segment 49 away from the straight edge segment 47 and the first connection portion 21 is greater than or equal to 1.4 mm, so that the distance between the end of the second arc segment 49 away from the straight edge segment 47 and the first connection portion 21 is large enough to ensure that when the second arc segment 49 is hemmed, the fourth insulating portion 35 on the peripheral edge of the first connection portion 21 will not interfere with the hemming equipment.

[0106] It should be noted that the distance between the end of the second arc segment 49 away from the straight edge segment 47 and the first connecting portion 21 may be 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm or 1.8 mm, etc., which is not particularly limited herein.

[0107] Specifically in the embodiment, the first fixing portion 40 includes a vertical edge sub-portion 41 and a flanged edge sub-portion 43. The vertical edge sub-portion 41 is connected to the first surface a1 of the cover plate 10. The flanged edge sub-portion 43 is connected to the vertical edge sub-portion 41, and the flanged edge sub-portion 43 is bent relative to the vertical edge sub-portion 41 to the step surface a6 of the second insulating portion 34, so that the flanged edge sub-portion 43 is used to press the second insulating portion 34, thereby realizing the first insulating member 30 and the pole 20 being pressed and fixed on the cover plate 10.

[0108] Furthermore, an insulating gap 430 is formed between the end of the flange sub-portion 43 away from the vertical side sub-portion 41 and the second region 222 of the second connecting portion 22. Part of the second insulating portion 34 is filled in the insulating gap 430, thereby achieving insulation between the flange sub-portion 43 and the second region 222 of the second connecting portion 22.

[0109] In order to more stably press the second connection portion 22 onto the cover plate 10, in some embodiments, the orthographic projection of the flange sub-portion 43 on the cover plate 10 along the thickness direction of the cover plate 10 is a first orthographic projection, and the orthographic projection of the second connection portion 22 on the cover plate 10 along the thickness direction of the cover plate 10 is a second orthographic projection. The first orthographic projection of the flange sub-portion 43 partially overlaps with the second orthographic projection of the second connection portion 22, that is, there is an overlapping portion between the flange sub-portion 43 and the second connection portion 22 in the thickness direction of the cover plate 10.

[0110] In other embodiments, the first orthographic projection of the flange sub-portion 43 does not overlap with the second orthographic projection of the second connecting portion 22 , that is, there is no overlapping portion between the flange sub-portion 43 and the second connecting portion 22 in the thickness direction of the cover plate 10 .

[0111] It should also be noted that, since each second connection part 22 is pressed against the cover plate 10 by the first fixing part 40, and the bonding between the first connection part 21 and the cover plate 10 is weak, the pole 20 may be unevenly stressed and warp or even crack. In order to prevent the pole 20 from warping or cracking due to uneven stress, in some embodiments, a second groove 210 is provided on the surface of the first connection part 21 facing the cover plate 10, and a third groove 12 is provided on the surface of the cover plate 10 facing the first connection part 21. Part of the first insulating part 31 is filled in the second groove 210, and part of the first insulating part 31 is also filled in the third groove 12. In this way, when the first insulating part 30 is injection molded, the molten injection material can flow into the second groove 210 and the third groove 12, and after solidification, a structure is formed in which part of the first insulating part 31 is filled in the second groove 210 and the third groove 12, which is conducive to improving the bonding force between the first connection part 21, the first insulating part 31 and the second connection part 22.

[0112] Further, at least a portion of the second groove 210 is gradually narrowed or stepped in a direction from the groove bottom to the groove opening, so that the first insulating portion 31 is closely nested in the pole 20 through the second groove 210, and the pole 20 is prevented from being separated from the first insulating member 30. At least a portion of the third groove 12 is gradually narrowed or stepped in a direction from the groove bottom to the groove opening, so that the first insulating portion 31 is closely nested in the cover plate 10 through the third groove 12, and the cover plate 10 is prevented from being separated from the first insulating member 30.

[0113] Optionally, the depth dimension of the second groove 210 is h1, the thickness dimension of the first connection part 21 is H1, and h1 and H1 satisfy: h1=(5%~50%)×H1. Preferably, h1 and H1 satisfy: h1=(10%~20%)×H1. In this way, by designing the depth of the second groove 210 within a suitable range, on the one hand, it is avoided that the depth of the second groove 210 is too shallow, resulting in the effect of increasing the bonding force between the first insulating part 31 and the first connection part 21 is not obvious; on the other hand, it is avoided that the depth of the second groove 210 is too deep, resulting in the first connection part 21 The strength is low and easy to deform. It should be noted that h1 can be 5%×H1, 10%×H1, 15%×H1, 20%×H1, 25%×H1, 30%×H1, 35%×H1, 40%×H1, 45%×H1 or 50%×H1, etc., and is not specifically limited here.

[0114] It should be noted that the number of the second grooves 210 can be one or more, and is not particularly limited here. When the number of the second grooves 210 is one, the second grooves 210 themselves are arranged symmetrically relative to the center line of the first connecting portion 21, so as to avoid the pole 20 from warping or cracking due to uneven force. When the number of the second grooves 210 is more than one, the multiple second grooves 210 are arranged symmetrically relative to the center line of the first connecting portion 21, so as to avoid the pole 20 from warping or cracking due to uneven force.

[0115] Optionally, the depth dimension of the third groove 12 is h2, the thickness dimension of the cover plate 10 is H2, and h2 and H2 satisfy: h2=(5%~50%)H2. Preferably, h2 and H2 satisfy: h2=(10%~20%)×H2. In this way, by designing the depth of the third groove 12 within a suitable range, on the one hand, the depth of the third groove 12 is avoided to be too shallow, resulting in the effect of increasing the bonding force between the first insulating part 31 and the cover plate 10 is not obvious; on the other hand, the depth of the third groove 12 is avoided to be too deep, resulting in the cover plate 10 being weak in strength and easy to deform. It should be noted that h2 can be 5%×H2, 10%×H2, 15%×H2, 20%×H2, 25%×H2, 30%×H2, 35%×H2, 40%×H2, 45%×H2 or 50%×H2, etc., and is not specifically limited here.

[0116] It should be noted that the number of the third grooves 12 can be one or more, and is not particularly limited here. When the number of the third grooves 12 is one, the third grooves 12 themselves are arranged symmetrically relative to the center line of the cover plate 10 to avoid defects such as warping or cracking of the cover plate 10 due to uneven force. When the number of the third grooves 12 is more than one, the multiple third grooves 12 are arranged symmetrically relative to the center line of the cover plate 10 to avoid defects such as warping or cracking of the cover plate 10 due to uneven force.

[0117] See also Figure 3 , Figure 6 and Figure 7 As shown, specifically in the embodiment, the top cover assembly 100 also includes a sealing ring 50, and the sealing ring 50 includes a first sealing portion 51 and a second sealing portion 53. The first sealing portion 51 and the second sealing portion 53 are both sleeved on the connecting sub-portion 223, and the first sealing portion 51 is located between the inner wall of the first through hole 11 and the connecting sub-portion 223, and the second sealing portion 53 is located between the surface of the side of the cover plate 10 away from the battery cell assembly 300 and the second area 222. In this way, on the one hand, the sealing ring 50 is used to seal the first through hole 11 on the cover plate 10 to prevent the electrolyte in the housing 200 from leaking out from the first through hole 11; on the other hand, the sealing ring 50 is used to form insulation between the connecting sub-portion 223 and the second area 222 and the cover plate 10 to prevent the pole 20 from being electrically connected to the cover plate 10. It should be noted that under the pressing action of the flange sub-portion 43, the first sealing portion 51 and the second sealing portion 53 of the sealing ring 50 are in a compressed state, thereby achieving sealing of the first through hole 11.

[0118] Furthermore, the first surface a1 of the cover plate 10 has a first convex strip 13 disposed around the first through hole 11. The second sealing portion 53 presses against the first convex strip 13, which is beneficial to increase the contact area between the sealing ring 50 and the cover plate 10, extend the sealing path, and improve the sealing effect.

[0119] It should be noted that the first ridge 13 is arranged around the first through hole 11 on the first surface a1 of the cover plate 10 , which can also strengthen the area of ​​the cover plate 10 near the first through hole 11 , thereby greatly reducing the risk of deformation or warping of the cover plate 10 .

[0120] Furthermore, the sealing ring 50 further includes a second convex strip 55. The second convex strip 55 is protrudingly arranged on the side of the second sealing portion 53 away from the cover plate 10, and is arranged around the second area 222. That is, the second sealing portion 53 is in contact with the entire surface of the second area 222 facing the cover plate 10, and the second convex strip 55 on the second sealing portion 53 also extends to the end surface of the second area 222, which is conducive to further improving the sealing effect.

[0121] Furthermore, the second ridge 55 extends along the peripheral edge of the second region 222 in a C shape, and the opening of the second ridge 55 faces the first connection portion 21. In this way, since the second region 222 of the second connection portion 22 is connected to the first connection portion 21 through the transition portion 23, the second ridge 55 is set to be C-shaped, and the space at the opening of the second ridge 55 is used for the transition portion 23 to pass through, so as to avoid interference between the second ridge 55 and the transition portion 23.

[0122] Specifically in the embodiment, on a virtual plane perpendicular to the thickness direction of the cover plate 10, the orthographic projection of the first connecting portion 21 does not overlap with the orthographic projection of the first through hole 11, and the orthographic projection of the second connecting portion 22 covers the orthographic projection of the first through hole 11, so that the position where the first connecting portion 21 is welded to the electrical connector is sufficiently far away from each second connecting portion 22, and then when the electrical connector is welded to the boss 211 of the first connecting portion 21, the adverse effect of the heat generated by the welding on the first insulating member 30 and the sealing ring 50 is greatly reduced, which is beneficial to reduce the risk of cracking or hot melting of the first insulating member 30 and improve the sealing reliability of the sealing ring 50.

[0123] It should be noted that the top cover assembly 100 can be assembled by pre-injection molding or integral injection molding. Fig. 9 As shown, the pre-injection method refers to: first, the pole 20 is formed by a stamping process; then, the first insulating member 30 is injection-molded on the pole 20, so that the pole 20 and the first insulating member 30 form a whole; then, the sealing ring 50 is sleeved on the connecting sub-portion 223 of the pole 20, and the connecting sub-portion 223 of the pole 20 is inserted into the first through hole 11 on the cover plate 10; then, the first fixing portion 40 is rolled, so that the flanged sub-portion 43 of the first fixing portion 40 is bent onto the second insulating portion 34 of the first insulating member 30, so that the pole 20 and the first insulating member 30 are pressed tightly on the cover plate 10, and the sealing ring 50 is compressed at the same time, so that the sealing ring 50 seals the first through hole 11.

[0124] In the pre-injection method, since the first fixing portion 40 is rolled to a folded state after the first insulating member 30 is injection-molded, the second insulating portion 34 of the injection-molded first insulating member 30 does not cover the first fixing portion 40 .

[0125] See also Figure 3As shown, the one-piece injection molding method means: first, the pole 20 is formed by a stamping process; then, the sealing ring 50 is sleeved on the connecting sub-portion 223 of the pole 20, and the connecting sub-portion 223 is inserted into the first through hole 11 on the cover; then, the pole 20, the sealing ring 50 and the cover plate 10 are loaded into the injection mold as a whole for injection molding, and the first insulating member 30 is injection molded (the flanged sub-portion 43 of the first fixing portion 40 has been rolled when the first insulating member 30 is injection molded), and the pole 20 is pressurized during the process of injection molding the first insulating member 30, so that the pole 20 compresses the sealing ring 50, that is, the sealing ring 50 maintains a certain amount of compression; after the injection molding is completed, the cover plate 10, the sealing ring 50, the pole 20 and the first insulating member 30 are removed from the injection mold as a whole. At this time, the pressure on the pole 20 disappears, but due to the pressing effect of the flange sub-portion 43 of the first fixing portion 40 on the first insulating member 30, the pole 20 and the first insulating member 30 can remain pressed against the cover plate 10, and the sealing ring 50 can also remain in a compressed state.

[0126] In the one-piece injection molding method, since the flanged sub-portion 43 of the first fixing portion 40 has been rolled to a folded state before the first insulating member 30 is injection-molded, the second insulating portion 34 of the injection-molded first insulating member 30 also covers the flanged sub-portion 43 and at least part of the vertical edge sub-portion 41 of the first fixing portion 40.

[0127] In some embodiments, the two second connection portions 22 are respectively located on both sides of the first connection portion 21 in the first preset direction. That is, one of the second connection portions 22, the first connection portion 21 and the other second connection portion 22 are arranged at intervals along the first preset direction (i.e., the width direction of the cover plate 10).

[0128] Of course, the positions of the two second connection parts 22 are not limited to being located on both sides of the first connection part 21, as long as the two second connection parts 22 are arranged along the first preset direction. In other embodiments, the two second connection parts 22 are located on the same side of the first connection part 21 in the second preset direction, and the second preset direction is consistent with the length direction of the cover plate 10. In this way, the two second connection parts 22 are arranged on the same side of the first connection part 21, and the size of the pole 20 in the width direction of the cover plate 10 is further reduced to adapt to the cover plate 10 with a narrower width.

[0129] The above describes an embodiment in which the pole 20 is installed on the cover plate 10, but the pole 20 is not limited to being installed on the cover plate 10. In other embodiments, the pole 20 can also be installed on the shell 200. Specifically, the battery cell 1 includes a shell 200, a battery cell assembly 300, a pole 20 and a first insulating member 30. The shell 200 has a receiving cavity and a first wall as a side wall of the receiving cavity, and the first wall has an inner side, an outer side and a first through hole 11. The inner side faces the receiving cavity, and the outer side faces away from the receiving cavity. The first through hole 11 passes through the inner side and the outer side. The battery cell assembly 300 is received in the receiving cavity of the shell 200, and has at least two pole ears 302 on the side facing the first wall. The pole 20 includes a first connecting portion 21 and at least two second connecting portions 22. The first connecting portion 21 is arranged on the outer side of the first wall, and each second connecting portion 22 is connected to the first connecting portion 21 and arranged along the width direction of the first wall. Each second connection portion 22 is at least partially disposed in the first through hole 11 and is respectively connected to the corresponding tab 302. The first insulating member 30 includes a first insulating portion 31 disposed between the first connection portion 21 and the first wall to form insulation.

[0130] It should be noted that the difference between the embodiment in which the pole 20 is installed on the first wall of the housing 200 and the embodiment in which the pole 20 is installed on the cover plate 10 is only the different installation position of the pole 20. The other structures are the same and will not be described in detail here.

[0131] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0132] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A top cover assembly, characterized in that: include: A cover plate (10) comprising a first surface (a1), a second surface (a2) and a first through hole (11), wherein the first surface (a1) and the second surface (a2) are opposite to each other, and the first through hole (11) passes through the first surface (a1) and the second surface (a2); A pole (20), comprising at least one first connection portion (21) and at least two second connection portions (22), wherein the first connection portion (21) is located on a side of the cover plate (10) having the first surface (a1), and each of the second connection portions (22) is connected to the first connection portion (21) and arranged along a first preset direction; each of the second connection portions (22) is at least partially disposed in the first through hole (11) and is used to be connected to a pole lug respectively; and The first insulating member (30) comprises a first insulating portion (31) arranged between the first connecting portion (21) and the cover plate (10).

2. The top cover assembly according to claim 1, characterized in that: On a virtual plane perpendicular to the thickness direction of the cover plate (10), the orthographic projection of the first connecting portion (21) does not overlap with the orthographic projection of the first through hole (11), and the orthographic projection of the second connecting portion (22) covers the orthographic projection of the first through hole (11).

3. The top cover assembly according to claim 1 or 2, characterized in that: Each second connecting portion (22) comprises a first region (221) and a second region (222) arranged around the first region (221); the second region (222) is connected to the first connecting portion (21); the first region (221) protrudes relative to the second region (222) along a direction from the first surface (a1) to the second surface (a2), and forms a connecting sub-portion (223) penetrating the first through hole (11).

4. The top cover assembly according to claim 3, characterized in that: One end of the connecting sub-portion (223) away from the second area (222) is a welding end (a3), the welding end (a3) ​​has a welding surface (a4), and the welding end (a3) ​​protrudes from the second surface (a2) of the cover plate (10).

5. The top cover assembly according to claim 4, characterized in that: The top cover assembly further comprises a second insulating member (60), wherein the second insulating member (60) is arranged on a second surface (a2) of the cover plate (10), the welding end (a3) ​​passes through the second insulating member (60), and the welding surface (a4) protrudes from a side surface of the second insulating member (60) away from the cover plate (10), or the welding surface (a4) is flush with a side surface of the second insulating member (60) away from the cover plate (10).

6. The top cover assembly according to claim 4, characterized in that: The distance that the welding end (a3) ​​protrudes from the second surface (a2) along the thickness direction of the cover plate (10) is 0 to 5 mm.

7. The top cover assembly according to claim 4, characterized in that: The distance between the weld mark on the welding surface (a4) and the edge of the welding surface (a4) is greater than or equal to 1 mm.

8. The top cover assembly according to claim 3, characterized in that: The first insulating member (30) further comprises a second insulating portion (34), and at least a portion of the second insulating portion (34) covers the second region (222).

9. The top cover assembly according to claim 8, characterized in that: The first insulating portion and the second insulating portion are integrally formed.

10. The top cover assembly according to claim 8, characterized in that: A first groove (225) is provided on an end surface of the connecting sub-part (223) connected to the second region (222), and the second insulating part (34) also covers the inner wall of the first groove (225).

11. The top cover assembly according to claim 10, characterized in that: The second insulating portion (34) is recessed toward the first groove (225) to form a pit (341).

12. The top cover assembly according to claim 8, characterized in that: The top cover assembly (100) further comprises a first fixing portion (40), the first fixing portion (40) being connected to the first surface (a1) of the cover plate (10) and pressing against a side of the second insulating portion (34) facing away from the cover plate (10).

13. The top cover assembly according to claim 12, characterized in that: The first fixing portion (40) extends along a peripheral edge of the second connecting portion (22).

14. The top cover assembly according to claim 13, characterized in that: The first fixing portion (40) comprises a first arc segment (45), a straight edge segment (47) and a second arc segment (49) which are connected in sequence, and the first arc segment (45) and the second arc segment (49) are both located on a side of the straight edge segment (47) facing the first connecting portion (21); an escape space (a5) is formed between an end of the first arc segment (45) away from the straight edge segment (47) and an end of the second arc segment (49) away from the straight edge segment (47).

15. The top cover assembly according to claim 14, characterized in that: The center angle of the first arc segment (45) is greater than 90°; and / or The center angle of the second arc segment (49) is greater than 90°.

16. The top cover assembly according to claim 14, characterized in that The distance between the end of the first arc segment (45) away from the straight edge segment (47) and the first connecting portion (21) is greater than or equal to 1.4 mm; and / or The distance between an end of the second arc segment (49) away from the straight edge segment (47) and the first connecting portion (21) is greater than or equal to 1.4 mm.

17. The top cover assembly according to claim 12, characterized in that: The first fixing portion (40) comprises a vertical edge sub-portion (41) and a flanged edge sub-portion (43); the vertical edge sub-portion (41) is connected to the first surface (a1) of the cover plate (10); the flanged edge sub-portion (43) is connected to the vertical edge sub-portion (41) and is bent relative to the vertical edge sub-portion (41) to a side of the second insulating portion (34) facing away from the cover plate (10).

18. The top cover assembly according to claim 17, characterized in that An insulating gap (430) is provided between one end of the flange sub-portion (43) facing away from the vertical edge sub-portion (41) and the second region (222), and a portion of the second insulating portion (34) is filled in the insulating gap (430).

19. The top cover assembly according to claim 17, characterized in that: The second insulating portion (34) also covers the flange sub-portion and at least a portion of the vertical edge sub-portion; or The second insulating portion (34) does not cover the vertical edge sub-portion (41) and the flange sub-portion (43).

20. The top cover assembly according to claim 17, characterized in that The orthographic projection of the flange sub-portion (43) on the cover plate (10) along the thickness direction of the cover plate (10) is a first orthographic projection, and the orthographic projection of the second connection portion (22) on the cover plate (10) along the thickness direction of the cover plate (10) is a second orthographic projection; the first orthographic projection and the second orthographic projection partially overlap or do not overlap.

21. The top cover assembly according to claim 1 or 2, characterized in that: The pole (20) further comprises a plurality of transition portions (23) corresponding one-to-one to each of the second connection portions (22), and each of the transition portions (23) is connected between the first connection portion (21) and the corresponding second connection portion (22).

22. The top cover assembly according to claim 21, characterized in that Each of the transition portions (23) is provided with a second through hole (231); each of the second connecting portions (22) comprises a first region (221) and a second region (222) arranged around the first region (221); the second region (222) is connected to the first connecting portion (21); the first region (221) protrudes relative to the second region (222) along a direction from the first surface (a1) to the second surface (a2), and forms a connecting sub-portion (223) penetrating the first through hole (11); The first insulating member (30) further comprises a second insulating portion (34) and a third insulating portion (32), wherein the second insulating portion (34) at least partially covers the second region (222), the third insulating portion (32) is filled in the second through hole (231), and the third insulating portion (32) is connected to the first insulating portion (31) and the second insulating portion (34).

23. The top cover assembly according to claim 22, characterized in that The first insulating portion (31), the second insulating portion (34) and the third insulating portion (32) are integrally formed.

24. The top cover assembly according to claim 3, characterized in that The top cover assembly (100) further comprises a sealing ring (50), wherein the sealing ring (50) comprises a first sealing portion (51) and a second sealing portion (53), wherein the first sealing portion (51) and the second sealing portion (53) are both sleeved on the connecting sub-portion (223), wherein the first sealing portion (51) is located between the connecting sub-portion (223) and the inner wall of the first through hole (11), and the second sealing portion (53) is located between the second area (222) and the first surface (a1) of the cover plate (10).

25. The top cover assembly according to claim 24, characterized in that The first surface (a1) of the cover plate (10) has a first convex strip (13) arranged around the first through hole (11), and the second sealing portion (53) is pressed against the first convex strip (13).

26. The top cover assembly according to claim 24, characterized in that The sealing ring (50) further comprises a second convex strip (55), the second convex strip (55) being protrudingly arranged on a side of the second sealing portion (53) facing away from the cover plate (10) and being arranged around the second area (222).

27. The top cover assembly according to claim 26, characterized in that The second convex strip (55) is C-shaped, and the opening of the second convex strip (55) faces the first connecting portion (21).

28. The top cover assembly according to claim 1 or 2, characterized in that: A second groove (210) is provided on a side of the first connecting portion (21) facing the cover plate (10), and a portion of the first insulating portion (31) is filled in the second groove (210).

29. The top cover assembly according to claim 28, characterized in that The second groove (210) is at least partially gradually narrowed or stepped narrowed in a direction from the groove bottom to the groove opening.

30. The top cover assembly according to claim 28, characterized in that The depth dimension of the second groove (210) is h1, the thickness dimension of the first connection portion (21) is H1, and h1 and H1 satisfy: h1=(5%-50%)H1.

31. The top cover assembly according to claim 1 or 2, characterized in that: A third groove (12) is provided on the surface of the cover plate (10) facing the first connecting portion (21), and a portion of the first insulating portion (31) is filled in the third groove (12).

32. The top cover assembly according to claim 31, characterized in that The third groove (12) is gradually narrowed or stepped in a direction from the groove bottom to the groove mouth.

33. The top cover assembly according to claim 31, characterized in that The depth dimension of the third groove (12) is h2, the thickness dimension of the cover plate (10) is H2, and h2 and H2 satisfy: h2=(5%-50%)H2.

34. The top cover assembly according to claim 1 or 2, characterized in that: The first connection portion (21) has a boss (211) and an annular surface (213) on a side facing away from the cover plate (10); the annular surface (213) is arranged around the boss (211), and the boss (211) is arranged to protrude relative to the annular surface (213) in a direction facing away from the cover plate (10); The first insulating member (30) further comprises a fourth insulating portion (35), wherein the fourth insulating portion (35) is arranged around the first connecting portion (21) and covers a peripheral edge of the first connecting portion (21); The surface of the fourth insulating portion (35) is flush with the annular surface.

35. The top cover assembly according to claim 1 or 2, characterized in that: The number of the second connection parts (22) is two, and the two second connection parts (22) are respectively located on two sides of the first connection part (21) in the first preset direction; or Each of the second connection portions (22) is located on the same side of the first connection portion (21) in a second preset direction, and the first preset direction is perpendicular to the second preset direction.

36. A battery cell, characterized in that: Comprising a housing, a battery cell assembly and a top cover assembly (100) according to any one of claims 1 to 35; The shell has a receiving cavity and an opening connected to the receiving cavity, the cover plate (10) is arranged to cover the opening, the battery cell assembly is arranged in the receiving cavity, and has at least two pole lugs on a side facing the cover plate (10), and each second connection portion (22) is connected to the corresponding pole lug by passing through the first through hole (11) into the receiving cavity.

37. A battery cell, characterized in that: include: A housing having a receiving cavity and a first wall as a side wall of the receiving cavity, wherein the first wall has an inner side surface, an outer side surface and a first through hole, wherein the inner side surface faces the receiving cavity, the outer side surface faces away from the receiving cavity, and the first through hole passes through the inner side surface and the outer side surface; A battery cell assembly is accommodated in the accommodation cavity of the shell and has at least two tabs on a side facing the first wall; A pole, comprising a first connection portion and at least two second connection portions, wherein the first connection portion is arranged on the outer side of the first wall, each of the second connection portions is connected to the first connection portion and arranged along the width direction of the first wall; each of the second connection portions is at least partially passed through the first through hole and is respectively connected to the corresponding pole lug; and The first insulating member includes a first insulating portion disposed between the first connecting portion and the first wall.

38. A battery, characterized in that: Comprising a battery cell as claimed in claim 36 or 37.

39. An electrical device, characterized in that: Includes the battery cell as claimed in claim 36 or 37, or includes the battery as claimed in claim 38.

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