Top cover assembly, battery monomer, battery and electric device

Abstract

The utility model 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; and each second connecting part is at least partially arranged in the first through hole in a penetrating manner and is used for being respectively connected with the tab.

Description

Technical Field

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

[0002] Lithium-ion batteries have advantages such as high energy density, long cycle life, high rate performance, good safety, and environmental friendliness, making them an important energy product for modern electronic products and electric vehicles. The battery cell is a crucial component of the battery.

[0003] There are two technical solutions for battery cells: those with adapter plates and those without. In the adapter plate solution, the tabs of the cell are connected to the terminals via adapter plates, making the terminals the electrode terminals of the battery cell. However, the presence of adapter plates increases the number of parts, thus increasing the cost of the battery cell; furthermore, it adds a welding process between the tabs and the adapter plate, further increasing the cost of the battery cell.

[0004] In adapter-less designs, the terminal and tab are directly connected. However, due to limited space on the cover plate, the position of the terminal is restricted, necessitating the use of extended tabs to achieve direct connection. Extended tabs significantly increase the risk of the tab being inserted backwards into the cell and of the tab tearing. Utility Model Content

[0005] Therefore, it is necessary to provide a top cover assembly, battery cell, battery, and power device that can eliminate the need for adapters and avoid lengthening the electrode tabs, in order to address the above problems.

[0006] On one hand, this application provides a top cover assembly, including:

[0007] A cover plate having 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 both the first surface and the second surface; and

[0008] The pole post includes at least one first connecting part and at least two second connecting parts. The first connecting part is located on the side of the cover plate having the first surface. Each of the second connecting parts is connected to the first connecting part and is arranged along the first preset direction. Each of the second connecting parts is at least partially inserted into the first through hole and is used to connect to the electrode tab respectively.

[0009] In some embodiments, on a dummy plane perpendicular to the thickness direction of the cover plate, the orthographic projection of the first connecting portion does not coincide 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.

[0010] In some embodiments, each of the second connecting portions includes a first region and a second region arranged around the first region, the second region being connected to the first connecting portion, the first region protruding relative to the second region in a direction from the first surface to the second surface, and forming a connecting sub-port passing through the first through hole.

[0011] In some embodiments, the end of the connecting sub-part away from the second region is a welding end, the welding end having a welding surface, and the welding end protruding from the second surface of the cover plate.

[0012] In some embodiments, the top cover assembly further includes a second insulating member disposed on a second surface of the cover plate, the welding end being disposed through the second insulating member, the welding surface protruding from the side surface of the second insulating member away from the cover plate, or the welding surface being flush with the side surface of the second insulating member away from the cover plate.

[0013] In some embodiments, the welding end protrudes from the second surface along the thickness direction of the cover plate by a distance of 0 to 5 mm.

[0014] In some 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.

[0015] In some embodiments, the top cover assembly further includes a first insulating member, the first insulating member including a first insulating portion and a second insulating portion, the first insulating portion being disposed between the first connecting portion and the cover plate, and at least a portion of the second insulating portion covering the second area.

[0016] In some embodiments, the first insulating portion and the second insulating portion are integrally formed.

[0017] In some embodiments, the end face of the connecting sub-part that connects to the second region has a first groove, and the second insulating part also covers the inner wall of the first groove.

[0018] In some embodiments, the second insulating portion is recessed into the first groove to form a pit.

[0019] In some embodiments, the top cover assembly further includes a first fixing portion connected to the first surface of the cover plate and pressing against the side of the second insulating portion away from the cover plate.

[0020] In some embodiments, the first fixing portion extends along the peripheral edge of the second connecting portion.

[0021] In some embodiments, the first fixing part includes a first arc segment, a straight edge segment, and a second arc segment connected in sequence, and both the first arc segment and the second arc segment are located on the side of the straight edge segment facing the first connecting part; a clearance space is formed between the end of the first arc segment away from the straight edge segment and the end of the second arc segment away from the straight edge segment.

[0022] In some embodiments, the central angle of the first arc segment is greater than 90°; and / or

[0023] The central angle of the second arc segment is greater than 90°.

[0024] In some embodiments, the distance between the 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

[0025] The distance between the end of the second arc segment furthest from the straight edge segment and the first connecting portion is greater than or equal to 1.4 mm.

[0026] In some embodiments, the first fixing part includes a standing edge part and a flanged edge part, the standing edge part being connected to the first surface of the cover plate, the flanged edge part being connected to the standing edge part and bent relative to the standing edge part to the side of the second insulating part away from the cover plate.

[0027] In some embodiments, an insulating gap exists between the end of the flange portion away from the upright portion and the second region, and a portion of the second insulating portion fills the insulating gap.

[0028] In some embodiments, the second insulating portion also covers the flanged portion and at least part of the upright portion; or

[0029] The second insulating part does not cover the standing edge part and the flanged edge part.

[0030] In some embodiments, the orthographic projection of the flanged portion onto 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 onto the cover plate along the thickness direction of the cover plate is a second orthographic projection; the first orthographic projection and the second orthographic projection may or may not overlap.

[0031] In some embodiments, the pole post further includes a plurality of transition portions corresponding one-to-one with each of the second connecting portions, each of the transition portions being connected between the first connecting portion and the corresponding second connecting portion.

[0032] In some embodiments, each of the second connecting portions includes a first region and a second region arranged around the first region, the second region being connected to the first connecting portion, the first region protruding relative to the second region in a direction from the first surface to the second surface, and forming a connecting sub-port passing through the first through hole;

[0033] Each of the transition portions is provided with a second through hole, and the top cover assembly further includes a first insulating member, the first insulating member including a second insulating portion and a third insulating portion, the second insulating portion at least partially covering the second region, the third insulating portion filling the second through hole, and the third insulating portion being connected to the second insulating portion.

[0034] In some embodiments, the second insulating portion and the third insulating portion are integrally formed.

[0035] In some embodiments, the top cover assembly further includes a sealing ring comprising a first sealing portion and a second sealing portion, both of which are sleeved on the connecting sub-part. The first sealing portion is located between the connecting sub-part and the inner wall of the first through hole, and the second sealing portion is located between the second region and the first surface of the cover plate.

[0036] In some embodiments, the first surface of the cover plate has a first protrusion surrounding the first through hole, and the second sealing portion abuts against the first protrusion.

[0037] In some embodiments, the sealing ring further includes a second protrusion that protrudes from the second sealing portion on the side opposite to the cover plate and is arranged around the second region.

[0038] In some embodiments, the second protrusion is C-shaped, and the opening of the second protrusion faces the first connecting portion.

[0039] In some embodiments, the first connecting portion has a second groove on the side facing the cover plate, and a portion of the first insulating portion fills the second groove.

[0040] In some embodiments, the second groove at least partially narrows or tapers in a stepwise manner in the direction from the bottom of the groove to the opening.

[0041] In some embodiments, the depth dimension of the second groove is h1, and the thickness dimension of the first connection is H1, wherein h1 and H1 satisfy: h1 = (5% ~ 50%)H1.

[0042] In some embodiments, the cover plate has a third groove on the surface facing the first connection portion, and a portion of the first insulating portion fills the third groove.

[0043] In some embodiments, the third groove gradually narrows or tapers from the bottom to the opening.

[0044] In some embodiments, the depth dimension of the third groove is h2, and the thickness dimension of the cover plate is H2, wherein h2 and H2 satisfy: h2 = (5% ~ 50%)H2.

[0045] In some embodiments, the first connecting portion has a boss and an annular surface on the side away from the cover plate, the annular surface being arranged around the boss, and the boss being convex relative to the annular surface in a direction away from the cover plate.

[0046] The top cover assembly further includes a first insulating member, which includes a fourth insulating portion arranged around the first connecting portion and covering the peripheral edge of the first connecting portion.

[0047] In some embodiments, there are two second connecting portions, each located on one side of the first connecting portion in the first preset direction; or

[0048] Each of the second connecting portions is located on the same side of the first connecting portion in the second preset direction, and the first preset direction is perpendicular to the second preset direction.

[0049] On the other hand, this application provides a battery cell, including a housing, a cell assembly, and a top cover assembly as described in any of the above embodiments;

[0050] The housing has a receiving cavity and an opening communicating with the receiving cavity. A cover plate is placed over the opening. The battery cell assembly is disposed in the receiving cavity and has at least two tabs on the side facing the cover plate. Each second connection portion extends through the first through hole into the receiving cavity and is connected to the corresponding tab.

[0051] On the other hand, this application provides a single battery cell, comprising:

[0052] The housing has a receiving cavity and a first wall serving as a side wall of the receiving cavity. The first wall has an inner side, an outer side, and a first through hole. The inner side faces the receiving cavity, the outer side faces away from the receiving cavity, and the first through hole penetrates the inner side and the outer side.

[0053] A battery cell assembly, housed within the receiving cavity of the housing, and having at least two tabs on the side facing the first wall; and

[0054] The pole post includes a first connecting part and at least two second connecting parts. The first connecting part is disposed on the outer side of the first wall. Each of the second connecting parts is connected to the first connecting part and is arranged along the width direction of the first wall. Each second connecting part is at least partially inserted into the first through hole and is respectively connected to the corresponding pole tab.

[0055] On the other hand, this application provides a battery characterized by comprising a battery cell as described in any of the above embodiments.

[0056] On the other hand, this application provides an electrical device that includes a battery cell as described in any of the above embodiments, or includes a battery as described in any of the above embodiments.

[0057] Compared with the prior art, this application has the following beneficial effects:

[0058] The aforementioned top cover assembly, battery cells, battery, and electrical device have terminals that are directly connected to the tabs of the two sets of cells via two second connecting parts. This avoids the use of adapter plates, thereby reducing the number of components in the top cover assembly and eliminating one welding process. Furthermore, by arranging the two second connecting parts along the arrangement direction of the two sets of cells, the two second connecting parts pass through the first through hole in the cover plate and connect to the tabs of the two sets of cells respectively. This avoids the need to increase the radial dimension of the terminals and extend the tabs, thus avoiding increased material costs for the tabs and the increased risk of adverse phenomena such as tabs being inserted backwards into the cells and tabs tearing. Attached Figure Description

[0059] Figure 1 This is a cross-sectional view of a battery cell at the terminal post in one embodiment of this application (the cross-section is perpendicular to the length direction of the cover plate);

[0060] Figure 2 for Figure 1 A schematic diagram of the top cover assembly of the battery cell shown;

[0061] Figure 3 for Figure 2 The exploded view of the top cover assembly is shown.

[0062] Figure 4 for Figure 2 The cross-sectional view of the top cover assembly shown (the cross-section is perpendicular to the length direction of the cover plate);

[0063] Figure 5 for Figure 2 A schematic diagram of the pole structure of the top cover assembly shown;

[0064] Figure 6 for Figure 5 The cross-sectional view of the pole shown (the cross-section is perpendicular to the length direction of the cover plate);

[0065] Figure 7 for Figure 2 A schematic diagram of the sealing ring structure of the top cover assembly shown;

[0066] Figure 8 for Figure 2 A schematic diagram of the cover plate of the top cover assembly shown;

[0067] Figure 9 for Figure 2 A schematic diagram of the structure of the first insulating component of the top cover assembly is shown;

[0068] Figure 10 This is a cross-sectional view of the top cover assembly at the pole in another embodiment of this application (the cross-section is perpendicular to the length direction of the cover plate). Detailed Implementation

[0069] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0070] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0071] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0072] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0073] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0074] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0075] One embodiment of this application provides an electrical device, a battery, and a battery cell. The electrical device includes a battery or a battery cell and is capable of providing electrical energy from the battery or the battery cell. The electrical device can be a vehicle, mobile phone, portable device, laptop computer, ship, spacecraft, electric toy, power tool, energy storage device, amusement equipment, elevator, and lifting equipment, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, or electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.; energy storage devices can be energy storage walls, base station energy storage, container energy storage, etc.; amusement equipment can be a carousel, a drop tower, etc.

[0076] The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended vehicles, etc. For new energy vehicles, the aforementioned battery can serve as a driving power source, thereby replacing fossil fuels to provide propulsion. This application does not impose any special restrictions on the aforementioned electrical devices.

[0077] The aforementioned battery can be a battery pack or a battery module. When the battery is a battery pack, the battery pack specifically includes a battery management system (BMS) and multiple battery cells. Multiple battery cells can be electrically connected in series, parallel, or a combination of series and parallel connections, and communicate with the battery management system, which controls and monitors the operating status of each battery cell. Alternatively, multiple battery cells can first be combined with a module management system to form a battery module, and then these battery modules can be electrically connected in series, parallel, or a combination of series and parallel connections to form a battery pack together with the battery management system.

[0078] Multiple battery cells can be mounted on supporting structures such as housings, frames, and brackets. Electrical connections between battery cells and between battery cells and the battery management system can be established via electrical connectors, which can be busbars. Alternatively, battery cells can be electrically connected via their respective terminals. For example, between two adjacent battery cells, one battery cell has a slot on its terminal, and the other battery cell has a corresponding insert on its terminal. The insert is inserted into the slot to achieve electrical connection. Therefore, for one battery cell, the aforementioned electrical connector can be the terminal of another battery cell. Similarly, battery cells and the battery management system can also be electrically connected via mutual insertion, which will not be elaborated further here. The aforementioned battery cells can be lithium-ion, sodium-ion, or magnesium-ion batteries, and their external contours can be cylindrical, flat, cuboid, or other shapes, but are not limited to these. Specifically, in this embodiment, the aforementioned battery cell is a lithium-ion square battery.

[0079] See Figure 1 The aforementioned battery cell 1 includes a housing 200, a cell assembly 300, and a top cover assembly 100. The housing 200 has an opening at at least one end and a receiving cavity communicating with the opening. The cell assembly 300 is housed within the receiving cavity of the housing 200, and the top cover assembly 100 covers the opening of the housing 200, thereby enclosing the cell assembly 300 within the receiving cavity of the housing 200. The cell assembly 300 includes at least two sets of cells 301 arranged side-by-side along the thickness direction of the housing 200, each set of cells 301 extending a tab 302 towards the end face of the top cover assembly 100.

[0080] It should be noted that each group of battery cells 301 can be a single battery cell 301 or multiple battery cells 301, and this is not limited here. When each group of battery cells 301 includes a single battery cell 301, the battery cell 301 extends a positive electrode tab and a negative electrode tab towards the end face 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 tab and a negative electrode tab towards the end face of the top cover assembly 100. The positive electrode tabs on the various battery cells 301 in the same group are brought together to form a single positive electrode tab, and the negative electrode tabs on the various battery cells 301 in the same group are brought together to form a single negative electrode tab.

[0081] In one embodiment, the battery cell assembly 300 includes two sets of battery cells 301, each set of battery cells 301 including one battery cell 301. That is, the battery cell assembly 300 includes a total of two battery cells 301. The two battery cells 301 are arranged side by side along the thickness direction of the housing 200. One battery cell 301 has a positive tab on its end face facing the top cover assembly 100 as a positive tab and a negative tab as a negative tab. The other battery cell 301 has a positive tab on its end face facing the top cover assembly 100 as another positive tab and a negative tab as another negative tab.

[0082] In related technologies, adapter plates are used to connect the positive tabs to the positive terminals on the top cover assembly. However, the presence of adapter plates increases the number of parts, leading to higher costs for individual battery cells, increased internal resistance, and reduced energy efficiency. Furthermore, the addition of a welding process between the tabs and the adapter plate further increases the cost of the battery cell. To overcome these drawbacks, adapter-free solutions have been developed.

[0083] In the adapter-less technical solution, the positive terminal on the top cover assembly extends directly into the housing cavity and connects directly to the positive tabs of each group of cells. However, since the cells are arranged along the thickness direction of the housing, the positive tabs of each group of cells are also arranged along the thickness direction of the housing. Because the span of each positive tab in the thickness direction of the housing is relatively large, the positive tabs need to be positioned in the middle of the housing thickness direction. Therefore, a standard-sized positive terminal cannot directly connect to each positive tab. Therefore, to achieve direct connection between the positive terminal and each positive tab, one approach is to increase the radial dimension of the terminal, making the terminal as close as possible to the positive tabs on both sides in the thickness direction of the housing, ensuring that each positive tab can be directly connected to the positive terminal; another approach is to extend the length of the positive tabs, allowing each positive tab to extend to the positive terminal and connect directly to it.

[0084] However, during long-term research and development, the inventors of this application discovered that in the scheme of increasing the radial dimension of the electrode post, the material cost of the electrode post increases with the increase of the radial dimension, and the size of the mounting hole used to install the electrode post is larger, resulting in insufficient strength of the cover plate of the top cover assembly. In the scheme of extending the length of the positive electrode tab, the risk of the electrode tab being inserted backward into the cell and the electrode tab tearing increases. It should be noted that the same defects exist when the negative electrode post is directly connected to the negative electrode tab, which will not be elaborated here.

[0085] To overcome the aforementioned deficiencies, the inventors of this application have creatively proposed a terminal post capable of directly connecting the terminal post and the tab. In the technical solution of this application, the terminal post is formed from sheet metal through a stamping process (such as upsetting, deep drawing, and cutting). The terminal post includes a first connecting portion and at least two second connecting portions connected to the first connecting portion. The at least two second connecting portions are arranged along a first preset direction, which is consistent with the thickness direction of the housing 200. That is, the arrangement direction of each second connecting portion is consistent with the arrangement direction of each group of battery cells 301, so that each second connecting portion is one-to-one with the tab 302 of each group of battery cells 301, thereby directly connecting the tab 302 of each group of battery cells 301 to their respective second connecting portions. This avoids the need to increase the radial dimension of the terminal post or extend the length of the tab 302, thus overcoming the defects caused by increasing the radial dimension of the terminal post and extending the tab 302.

[0086] The specific structure of the top cover assembly is described in detail below with reference to the accompanying drawings. Please refer to... Figures 1 to 6 As shown in the embodiment of this application, the top cover assembly 100 includes a cover plate 10 and an electrode post 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 disposed on the opening of the housing 200 to seal the opening of the housing 200. The first surface a1 of the cover plate 10 faces away from the cell assembly 300 in the receiving cavity of the housing 200, and the second surface a2 of the cover plate 10 faces the cell assembly 300 in the receiving cavity of the housing 200. The thickness direction of the housing 200 is consistent with the first preset direction, that is, the two sets of cells 301 of the cell assembly 300 in the housing 200 are arranged side by side along the first preset direction, so the electrodes 302 of the two sets of cells 30 are also arranged at intervals along the first preset direction.

[0087] The terminal post 20 is disposed on the cover plate 10, and the thickness direction of the terminal post 20 is consistent with the thickness direction of the cover plate 10. A positive terminal post and a negative terminal post can be disposed on the cover plate 10. The positive terminal post is used to connect to the positive tab of each group of battery cells 301, thereby leading the positive tab of each group of battery cells 301 out of the housing 200; the negative terminal post is used to connect to the negative tab of each group of battery cells 301, thereby leading the negative tab of each group of battery cells 301 out of the housing 200. The positive terminal post serves as the positive terminal of the battery cell 1, and the negative terminal post serves as the negative terminal of the battery cell 1. Electrical connectors are used to connect the positive and negative terminals of each battery cell 1 to achieve series, parallel, or mixed series and parallel connections of the battery cells 1.

[0088] It should be noted that, due to the similarity in structure between the positive and negative terminals, this article will use one of the terminals 20 as an example for ease of understanding. That is to say, the term "terminal" in this article can be either a positive or negative terminal (unless explicitly stated otherwise), and the term "tab" can be either a positive or negative tab (unless explicitly stated otherwise), as long as all tabs 302 connected to the positive terminal are positive tabs and all tabs 302 connected to the negative terminal are negative tabs.

[0089] Specifically, the electrode post 20 includes a first connecting portion 21 and two second connecting portions 22. The first connecting portion 21 is located on the side of the cover plate 10 with the first surface a1, and both second connecting portions 22 are connected to the first connecting portion 21. The two second connecting portions 22 are arranged along a first preset direction, that is, the arrangement direction of the two second connecting portions 22 is consistent with the arrangement direction of the tabs 302 of the two sets of battery cells 301. At least a portion of each second connecting portion 22 passes through the first through hole 11 on the cover plate 10 and is used to connect to the corresponding tab 302, that is, the two second connecting portions 22 are connected to the tabs 302 of the two sets of battery cells 301 in a one-to-one correspondence.

[0090] The aforementioned top cover assembly 100 has its pole post 20 directly connected to the tabs 302 of the two sets of battery cells 301 via two second connecting parts 22. This avoids the use of adapter plates, thereby reducing the number of parts in the top cover assembly 100 and eliminating one welding process. Furthermore, by arranging the two second connecting parts 22 along the arrangement direction of the two sets of battery cells 301, the two second connecting parts 22 pass through the first through hole 11 on the cover plate 10 and are connected to the tabs 302 of the two sets of battery cells 301 respectively. This avoids the need to increase the radial dimension of the pole post 20 and extend the tabs 302, thereby avoiding increased material costs for the tabs 302 and the risk of adverse phenomena such as the tabs 302 being inserted backwards into the battery cells or the tabs 302 being torn.

[0091] It is understood that the number of second connection parts 22 is not limited to two; it can also be three or more. The number of second connection parts 22 is related to the number of battery cell groups. Specifically, if there are N battery cell groups, the number of second connection parts 22 is also set to N. The N second connection parts 22 are arranged at intervals along a first preset direction and are all connected to the first connection part 21. The N second connection parts 22 are respectively passed through the first through holes 11 on the cover plate 10 and are connected one-to-one with the tabs 302 of each battery cell group 301, thereby leading the tabs 302 of their respective battery cells 301 to the first connection part 21. For ease of understanding, this article uses the example of a battery cell assembly 300 including two battery cells 301 and a terminal post 20 including two second connection parts 22 for explanation.

[0092] It should also be noted that the number of first connecting parts 21 is not limited to one; it can be two or more. The number of first connecting parts 21 is related to the number of second connecting parts 22. A first connecting part 21 is provided between two adjacent second connecting parts 22, in which case the number of first connecting parts 21 is N-1. For example, when the number of second connecting parts 22 is 3 and the number of first connecting parts 21 is 2, the pole post 20 includes, along the first preset direction, a second connecting part 22, a first connecting part 21, a second connecting part 22, a first connecting part 21, and a second connecting part 22 connected in sequence.

[0093] In one embodiment, a first through hole 11 may be provided on the cover plate 10. The first through hole 11 is a hole with a large area that allows at least two second connecting parts 22 to pass through the first through hole 11.

[0094] Understandably, in another embodiment, a first through hole 11 is provided on the cover plate 10 corresponding to each second connecting part 22, so that each second connecting part 22 passes through its corresponding first through hole 11 and is connected to its corresponding electrode tab 302. Thus, compared to installing the entire electrode post on the cover plate 10 with a single first through hole 11, this embodiment only requires a first through hole 11 matching the outer contour size of the second connecting part 22, greatly reducing the opening area on the cover plate 10, minimizing any adverse effects on the strength of the cover plate 10, and ensuring that the strength of the cover plate 10 meets the requirements.

[0095] Specifically, in the embodiment, on a dummy plane perpendicular to the thickness direction of the cover plate 10, the orthographic projection of the first connecting portion 21 does not coincide 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. This ensures that the welding position of the first connecting portion 21 to the electrical connector is sufficiently far from each of the second connecting portions 22. Consequently, when the electrical connector is welded to the first connecting portion 21, the heat generated during welding is greatly reduced on the first insulating component 30 (see...). Figure 3) and the following sealing ring 50 (see Figure 3 This reduces the risk of cracking or melting of the first insulating element 30 and improves the sealing reliability of the sealing ring 50.

[0096] Please see Figures 4 to 6 As shown in the embodiments of this application, each second connecting portion 22 includes 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 in a direction from the first surface a1 to the second surface a2, and forms a connecting sub-portion 223 passing through the corresponding first through hole 11. Thus, the first region 221 of the second connecting portion 22 can be drawn once or multiple times using a stamping process, so that the first region 221 protrudes relative to the second region 222 toward the cover plate 10 to form the connecting sub-portion 223. The connecting sub-portion 223 extends through the corresponding first through hole 11 to the corresponding electrode 302 of the battery cell assembly and is directly connected to the electrode 302.

[0097] Furthermore, the end of the connecting part 223 furthest from the second region 222 is a welding end a3, which passes through the corresponding first through hole 11 and enters the receiving cavity of the housing 200. That is, the welding end a3 of the connecting part 223 protrudes from the second surface a2 of the cover plate 10, thereby avoiding welding the tab 302 and the welding end a3 of the connecting part 223 inside the first through hole 11, greatly reducing the welding difficulty and improving the welding quality of the tab 302 and the welding end a3 of the connecting part 223.

[0098] Furthermore, the welding end a3 of the connecting part 223 protrudes from the second surface a2 of the cover plate 10 along the thickness direction of the cover plate 10 by a distance of 0 to 5 mm, thereby avoiding the large space occupied in the receiving cavity due to the welding end a3 protruding too far from the second surface a2, thus saving space in the receiving cavity of the housing 200 and helping to improve the energy density of the battery.

[0099] Furthermore, the top cover assembly 100 also includes a second insulating member 60, which is disposed on the second surface a2 of the cover plate 10 to form insulation between the cover plate 10 and the cell assembly 300. The second insulating member 60 has a third through hole opposite to the first through hole 11, and the connecting part 223 passes through the corresponding first through hole 11 and third through hole. The welding end a3 of the connecting part 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 the tab 302 and the welding surface a4 of the connecting part 223 is avoided inside the third through hole, which greatly reduces the welding difficulty and helps to improve the welding quality of the tab 302 and the welding surface a4 of the connecting part 223.

[0100] It should be noted that welding processes such as laser welding, resistance welding, ultrasonic welding, and pressure fusion welding can be used to weld the connecting part 223 to the tab 302.

[0101] As one embodiment, the tab 302 is welded and fixed to the connector 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., and is not specifically limited here.

[0102] It should be noted that the distance between the weld mark on the welding surface a4 and the edge of the welding surface a4 refers to the distance between any point on the edge of the welding surface a4 and any point on the edge of the weld mark.

[0103] In another embodiment, the tab 302 is welded and fixed to the connector 223 by pressure welding. Specifically, a protrusion 227 is provided on the welding surface a4 of the connector 223. During pressure 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, causing the protrusion 227 to melt and weld the tab 302 to the welding surface a4 of the connector 223. It is understood that the shape of the protrusion 227 can be spherical, hemispherical, frustum-shaped, etc., as long as it can ensure that the protrusion 227 can melt under the action of electrical energy and pressure to weld the tab 302 to the welding surface a4 of the connector 223. No limitation is made here.

[0104] Specifically, in this embodiment, the end face of the connecting sub-part 223 that connects to the second region 222 has a first groove 225, making the connecting sub-part 223 hollow. This helps to reduce the weight of the pole post 20 and save material. It can be understood that during one or more deep drawing processes of the sheet metal, the first region 221 of the sheet metal protrudes outward to one side relative to the second region 222, thereby forming the hollow connecting sub-part 223.

[0105] Optionally, the depth of the first groove 225 is 1mm to 5mm, preferably 1mm to 3mm. If the depth of the first groove 225 is too shallow, the welding end a3 of the connecting part 223 will be far from the cell assembly 300, requiring a longer tab 302; if the depth of the first groove 225 is too deep, the deep drawing process will be more difficult. In this embodiment, by reasonably designing the depth of the first groove 225, the depth of the first groove 225 is made moderate, which allows welding of the tab 302 to the welding end a3 of the connecting part 223 without lengthening the tab 302, while also reducing the difficulty of the deep drawing process, improving production efficiency and the yield of the electrode post 20.

[0106] It should be noted that the depth of the first groove 225 can be 1.0mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm, 3.5mm, 4.0mm, 4.5mm or 5.0mm, etc., and no special limitation is made here.

[0107] In the embodiments of this application, the pole post 20 further includes a transition portion 23, and the second region 222 of each second connecting portion 22 is connected to the first connecting portion 21 through the transition portion 23. The end of the transition portion 23 connected to the second region 222 of the second connecting portion 22 is the first end, and the first end protrudes at least partially from the side surface of the first connecting portion 21 facing the cover plate 10 along the thickness direction of the pole post 20. That is, the transition portion 23 extends obliquely relative to the thickness direction of the pole post 20 from the end connected to the first connecting portion 21 to the end connected to the second region 222, so that the second connecting portion 22 sinks towards the cover plate 10 relative to the first connecting portion 21, thereby making the connecting portion 223 closer to the corresponding tab 302, which is beneficial to minimize the drawing depth of the connecting portion 223, reduce the drawing difficulty, and improve the drawing quality of the pole post 20.

[0108] Furthermore, the current-carrying area of ​​the transition portion 23 is smaller than that of the first connecting portion 21 and smaller than that of the second connecting portion 22. Thus, in actual use, when a circuit malfunction occurs, the smaller current-carrying area of ​​the transition portion 23 causes it to heat up more quickly, allowing it to melt rapidly and promptly cut off the circuit, greatly improving battery safety. It is understood that the current-carrying area of ​​the transition portion 23 can be reduced by slotting, opening, and / or locally thinning to ensure timely melting and circuit disconnection in case of a circuit malfunction.

[0109] In embodiments of this application, the top cover assembly 100 further includes a first insulating member 30, which includes a first insulating portion 31. The first insulating portion 31 is disposed between the first connecting portion 21 of the pole post 20 and the cover plate 10 and forms an insulation, thereby preventing electrical conduction between the first connecting portion 21 of the pole post 20 and the cover plate 10.

[0110] Furthermore, the first insulating member 30 also includes a second insulating part 34, which covers the second region 222 of the pole post 20. On the one hand, it provides insulation protection for the outer surface of the second region 222, and on the other hand, it wraps the second region 222 of the pole post 20, which helps to increase the overall strength of the pole post 20 and reduce the risk of deformation of the pole post 20.

[0111] Furthermore, the second insulating part 34 also covers the inner wall of the first groove 225, which on the one hand provides insulation protection for the inner wall of the first groove 225, and on the other hand helps to increase the bonding force between the second insulating part 34 and the second connecting part 22, greatly reducing the risk of positional displacement or even separation between the second insulating part 34 and the second connecting part 22.

[0112] Furthermore, the second insulating part 34 is recessed into the first groove 225 to form a pit 341. That is to say, the second insulating part 34 only covers the inner wall of the first groove 225 and does not fill the first groove 225. On the one hand, this helps to improve the bonding force between the second insulating part 34 and the second connecting part 22 of the pole post 20, and avoids the separation or misalignment of the second insulating part 34 and the second connecting part 22. On the other hand, it reduces the amount of material used in the second insulating part 34 and avoids defects such as uneven injection molding due to excessive local thickness.

[0113] Furthermore, the second insulating portion 34 extends to each transition portion 23 and covers each transition portion 23, thereby providing insulation protection for 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 improving the overall strength of the pole post 20 and providing insulation protection for the peripheral edge of the first connecting portion 21. That is, the 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 surface of the first connecting portion 21 facing away from the cover plate 10 is not covered, and this uncovered surface is used for welding with electrical connectors.

[0114] Specifically, in this embodiment, the first connecting portion 21 has a boss 211 and an annular surface 213 on the side away from the cover plate 10. The annular surface 213 is arranged around the boss 211, and the boss 211 protrudes relative to the annular surface 213 in a direction away from the cover plate 10. An electrical connector is welded to the boss 211, and the fourth insulating portion 35 of the first insulating member 30 is lower than or flush with the annular surface 213. Thus, by providing the boss 211, during injection molding, the flow of injection molding material to the surface of the boss 211 can be prevented, causing the first insulating member 30 to cover the surface of the boss 211.

[0115] Optionally, the protrusion height of the boss 211 relative to the annular surface 213 is 0.05mm to 0.8mm, preferably 0.1mm to 0.6mm or 0.3mm to 0.5mm. It should be noted that the protrusion height of the boss 211 relative to the annular surface 213 can be 0.05mm, 0.20mm, 0.35mm, 0.50mm, 0.65mm or 0.8mm, etc., and is not specifically limited here.

[0116] In a specific embodiment, the transition portion 23 has at least one second through hole 231, 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, thereby making the first insulating portion 31, the second insulating portion 34, the third insulating portion 32, and the fourth insulating portion 35 form a whole. On the one hand, this helps to improve the bonding force between the first insulating member 30 and the pole post 20; on the other hand, it helps to further improve the overall strength of the pole post 20.

[0117] Furthermore, the first insulating portion 31, the second insulating portion 34, the third insulating portion 32, and the third insulating portion 33 of the first insulating member 30 are integrally formed, for example, by injection molding. During injection molding of the first insulating member 30, a portion of the molten injection material flows to the surface of each second connecting portion 22 and each transition portion 23, and solidifies to form the second insulating portion 34; a portion of the molten injection material flows to the surface of the peripheral edge of the first connecting portion 21, and solidifies to form the fourth insulating portion 35; a portion of the injection material flows into the second through hole 231, and solidifies to form the third insulating portion 32; a portion of the injection material flows through the second through hole 231 into the space between the first connecting portion 21 and the cover plate 10, and solidifies to form the first insulating portion 31 between the first connecting portion 21 and the cover plate 10.

[0118] It should be noted that the second through hole 231 on the transition section 23 serves two purposes: firstly, it facilitates the flow of injection molding material during injection molding; secondly, it reduces the flow area of ​​the transition section 23, ensuring that the transition section 23 can melt and cut off the circuit in time in case of an abnormality.

[0119] Please see also Figure 7 As shown, in a specific embodiment, the top cover assembly 100 further includes a first fixing part 40. The first fixing part 40 is fixedly connected to the first surface a1 of the cover plate 10, and a portion of the first fixing part 40 can be bent to the side surface of the second insulating part 34 away from the cover plate 10 by a rolling process, thereby using the first fixing part 40 to press the second insulating part 34 and the pole post 20 onto the cover plate 10, preventing the pole post 20 from detaching from the cover plate 10.

[0120] Furthermore, the second insulating portion 34 has a stepped 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 stepped surface a6, making the pressure of the first fixing portion 40 on the second insulating portion 34 more stable, thereby making the assembly structure of the pole post 20 and the cover plate 10 more stable and preventing the pole post 20 from shifting position or even detaching from the cover plate 10.

[0121] It should be noted that the number of first fixing parts 40 is the same as the number of second connecting parts 22, and they 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, thereby pressing each second connecting part 22 of the pole post 20 against the cover plate 10. Optionally, each first fixing part 40 extends in a C-shape along the peripheral edge of the corresponding second connecting part 22, 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 interference between 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 and the hemming equipment during the hemming of the first fixing part 40.

[0122] Specifically, the first fixing part 40 includes a first arc segment 45, a straight edge segment 47, and a second arc segment 49 connected in sequence, with both the first arc segment 45 and the second arc segment 49 located on the side of the straight edge segment 47 facing the first connecting part 21. A clearance space a5 is formed between the end of the first arc segment 45 away from the straight edge segment 47 and the end of the second arc segment 49 away from the straight edge segment 47. It can be understood that this clearance space a5 is the space at the opening of the C-shaped first fixing part 40.

[0123] 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 part 40, so that the first fixing part 40 can more firmly press the second insulating part 34 and the second connecting part 22 onto the cover plate 10.

[0124] 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 part 40, so that the first fixing part 40 can more firmly press the second insulating part 34 and the second connecting part 22 onto the cover plate 10.

[0125] It should be noted that in order to improve the pressing effect, the length of the first fixing part 40 needs to be extended as much as possible. However, extending the length of the first fixing part 40 will cause the distance between the end of the first arc segment 45 and / or the second arc segment 49 away from the straight edge segment 47 and the first connecting part 21 to be too close. This will cause the fourth insulating part 35 wrapped around the periphery of the first connecting part 21 to interfere with the rolling device when the first fixing part 40 is rolled.

[0126] To prevent interference between the fourth insulating portion 35, which wraps around the periphery of the first connecting portion 21, and the hemming equipment during the hemming operation of the first arc segment 45, 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. This ensures 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 sufficiently large to prevent interference between the fourth insulating portion 35 and the hemming equipment during the hemming operation of the first arc segment 45.

[0127] 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 part 21 can be 1.4mm, 1.5mm, 1.6mm, 1.7mm or 1.8mm, etc., and no special limitation is made here.

[0128] To prevent interference between the fourth insulating portion 35, which wraps around the periphery of the first connecting portion 21, and the hemming equipment during the hemming operation of the second arc segment 49, in some embodiments, the distance between the 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. This ensures 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 is sufficiently large to prevent interference between the fourth insulating portion 35 and the hemming equipment during the hemming operation of the second arc segment 49.

[0129] 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 part 21 can be 1.4mm, 1.5mm, 1.6mm, 1.7mm or 1.8mm, etc., and no special limitation is made here.

[0130] In a specific embodiment, the first fixing part 40 includes a standing edge part 41 and a flanged edge part 43. The standing edge part 41 is connected to the first surface a1 of the cover plate 10. The flanged edge part 43 is connected to the standing edge part 41, and the flanged edge part 43 is bent relative to the standing edge part 41 onto the stepped surface a6 of the second insulating part 34, thereby pressing the second insulating part 34 with the flanged edge part 43, thereby pressing and fixing the first insulating member 30 and the pole post 20 onto the cover plate 10.

[0131] Furthermore, an insulating gap 430 is provided between the end of the flanged portion 43 facing away from the upright portion 41 and the second region 222 of the second connecting portion 22. Part of the second insulating portion 34 fills the insulating gap 430, thereby achieving insulation between the flanged portion 43 and the second region 222 of the second connecting portion 22.

[0132] To more securely press the second connecting portion 22 onto the cover plate 10, in some embodiments, the orthographic projection of the flange portion 43 along the thickness direction of the cover plate 10 onto the cover plate 10 is a first orthographic projection, and the orthographic projection of the second connecting portion 22 along the thickness direction of the cover plate 10 onto the cover plate 10 is a second orthographic projection. The first orthographic projection of the flange portion 43 and the second orthographic projection of the second connecting portion 22 partially overlap, meaning that the flange portion 43 and the second connecting portion 22 overlap in the thickness direction of the cover plate 10.

[0133] In other embodiments, the first orthographic projection of the flange portion 43 does not coincide with the second orthographic projection of the second connecting portion 22, that is, the flange portion 43 and the second connecting portion 22 do not overlap in the thickness direction of the cover plate 10.

[0134] It should also be noted that, since each of the second connecting parts 22 is pressed onto the cover plate 10 by the first fixing part 40, and the bond between the first connecting part 21 and the cover plate 10 is relatively weak, the pole post 20 may experience uneven stress, leading to warping or even cracking. To prevent the pole post 20 from warping or cracking due to uneven stress, in some embodiments, a second groove 210 is formed on the surface of the first connecting part 21 facing the cover plate 10, and a third groove 12 is formed on the surface of the cover plate 10 facing the first connecting part 21. Part of the first insulating part 31 fills the second groove 210, and part of the first insulating part 31 also fills the third groove 12. Thus, 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, form a structure in which part of the first insulating part 31 fills the second groove 210 and the third groove 12, which helps to improve the bonding force between the first connecting part 21, the first insulating part 31, and the second connecting part 22.

[0135] Furthermore, at least a portion of the second groove 210 gradually narrows or tapers in a stepped manner from the bottom to the opening, thereby ensuring that the first insulating part 31 is tightly nested on the pole post 20, preventing the pole post 20 from separating from the first insulating member 30. At least a portion of the third groove 12 gradually narrows or tapers in a stepped manner from the bottom to the opening, thereby ensuring that the first insulating part 31 is tightly nested on the cover plate 10, preventing the cover plate 10 from separating from the first insulating member 30.

[0136] Optionally, the depth of the second groove 210 is h1, and the thickness of the first connecting portion 21 is H1, where h1 and H1 satisfy: h1 = (5%~50%) × H1. Preferably, h1 and H1 satisfy: h1 = (10%~20%) × H1. Thus, by designing the depth of the second groove 210 within a suitable range, on the one hand, it avoids the second groove 210 being too shallow, resulting in an insignificant effect on increasing the bonding force between the first insulating portion 31 and the first connecting portion 21; on the other hand, it avoids the second groove 210 being too deep, resulting in low strength of the first connecting portion 21 and easy deformation. 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.

[0137] It should be noted that the number of second grooves 210 can be one or more, and no special limitation is made here. When there is only one second groove 210, the second groove 210 is symmetrically arranged with respect to the center line of the first connecting part 21 to avoid defects such as warping or cracking of the pole post 20 due to uneven force. When there are multiple second grooves 210, the multiple second grooves 210 are symmetrically arranged with respect to the center line of the first connecting part 21 to avoid defects such as warping or cracking of the pole post 20 due to uneven force.

[0138] Optionally, the depth of the third groove 12 is h2, and the thickness of the cover plate 10 is H2, where h2 and H2 satisfy: h2 = (5% to 50%)H2. Preferably, h2 and H2 satisfy: h2 = (10% to 20%) × H2. Thus, by designing the depth of the third groove 12 within a suitable range, on the one hand, it avoids the third groove 12 being too shallow, resulting in an insignificant effect on increasing the bonding force between the first insulating part 31 and the cover plate 10; on the other hand, it avoids the third groove 12 being too deep, resulting in weak strength of the cover plate 10 and easy deformation. 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.

[0139] It should be noted that the number of third grooves 12 can be one or more, and no special limitation is made here. When there is only one third groove 12, the third groove 12 is symmetrically arranged with respect 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 there are multiple third grooves 12, the multiple third grooves 12 are symmetrically arranged with respect 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.

[0140] Please see Figure 3 , Figure 6 and Figure 7 As shown, in a specific embodiment, the top cover assembly 100 further includes a sealing ring 50, which includes a first sealing portion 51 and a second sealing portion 53. Both the first sealing portion 51 and the second sealing portion 53 are sleeved on the connecting sub-part 223. The first sealing ring 50 is located between the inner wall of the first through hole 11 and the connecting sub-part 223, and the second sealing portion 53 is located between the surface of the cover plate 10 facing away from the cell assembly 300 and the second region 222. Thus, on the one hand, the sealing ring 50 seals the first through hole 11 on the cover plate 10, preventing electrolyte leakage from the housing 200 through the first through hole 11; on the other hand, the sealing ring 50 forms insulation between the connecting sub-part 223, the second region 222, and the cover plate 10, preventing electrical conduction between the electrode post 20 and the cover plate 10. It should be noted that under the pressure of the flanged sub-part 43, the first sealing portion 51 and the second sealing ring 50 of the sealing ring 50 are in a compressed state, thereby sealing the first through hole 11.

[0141] Furthermore, the first surface a1 of the cover plate 10 has a first protrusion 13 surrounding the first through hole 11. The second sealing part 53 presses against the first protrusion 13, which helps to increase the contact area between the sealing ring 50 and the cover plate 10, extend the sealing path, and improve the sealing effect.

[0142] It should be noted that the first protrusion 13 is provided 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, greatly reducing the risk of deformation or warping of the cover plate 10.

[0143] Furthermore, the sealing ring 50 also includes a second protrusion 55. This second protrusion 55 protrudes from the side of the second sealing portion 53 facing away from the cover plate 10 and is arranged around the second region 222. That is, the second sealing portion 53 contacts the entire surface of the second region 222 facing the cover plate 10, and the second protrusion 55 on the second sealing portion 53 extends to the end face of the second region 222, which helps to further improve the sealing effect.

[0144] Furthermore, the second protrusion 55 extends in a C-shape along the peripheral edge of the second region 222, and the opening of the second protrusion 55 faces the first connecting portion 21. Thus, since the second region 222 of the second connecting portion 22 is connected to the first connecting portion 21 through the transition portion 23, the second protrusion 55 is set in a C-shape, utilizing the space at the opening of the second protrusion 55 for the transition portion 23 to pass through, thereby avoiding interference between the second protrusion 55 and the transition portion 23.

[0145] It should be noted that the top cover assembly 100 can be assembled using either pre-injection molding or one-piece injection molding. Please refer to [link / reference]. Figure 9 As shown, the pre-injection molding method refers to the following steps: First, the electrode post 20 is formed using a stamping process; then, the first insulating component 30 is injection molded onto the electrode post 20, so that the electrode post 20 and the first insulating component 30 form an integral whole; then, the sealing ring 50 is fitted onto the connecting part 223 of the electrode post 20, and the connecting part 223 of the electrode post 20 is inserted into the first through hole 11 on the cover plate 10; then, the first fixing part 40 is rolled, so that the flanged part 43 of the first fixing part 40 is bent onto the second insulating part 34 of the first insulating component 30, thereby pressing the electrode post 20 and the first insulating component 30 onto the cover plate 10, while compressing the sealing ring 50, so that the sealing ring 50 seals the first through hole 11.

[0146] In the pre-injection molding method, since the first fixing part 40 is rolled to a folded state after the first insulating part 30 is injection molded, the second insulating part 34 of the injection molded first insulating part 30 does not cover the first fixing part 40.

[0147] Please see Figure 3 As shown, the one-piece injection molding method refers to: first, forming the pole post 20 using a stamping process; then, fitting the sealing ring 50 onto the connecting part 223 of the pole post 20 and inserting the connecting part 223 into the first through hole 11 on the cover; then, inserting the pole post 20, the sealing ring 50, and the cover plate 10 as a whole into the injection mold for injection molding, and injection molding the first insulating part 30 (the flanged part 43 of the first fixing part 40 has been rolled during the injection molding of the first insulating part 30). During the injection molding of the first insulating part 30, pressure is applied to the pole post 20, so that the pole post 20 compresses the sealing ring 50, so that 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 post 20, and the first insulating part 30 are removed from the injection mold as a whole. At this time, the pressure on the pole post 20 disappears, but due to the pressing action of the flanged part 43 of the first fixing part 40 against the first insulating part 30, the pole post 20 and the first insulating part 30 can be kept pressed on the cover plate 10, and the sealing ring 50 can also be kept in a compressed state.

[0148] In the one-piece injection molding method, since the flanged part 43 of the first fixing part 40 has been rolled to a folded state before the first insulating part 30 is injection molded, the second insulating part 34 of the injection-molded first insulating part 30 also covers the flanged part 43 and at least part of the upright part 41 of the first fixing part 40.

[0149] In some embodiments, the two second connecting portions 22 are respectively located on both sides of the first connecting portion 21 in a first preset direction. That is, one of the second connecting portions 22, the first connecting portion 21 and the other second connecting portion 22 are arranged at intervals along the first preset direction (i.e., the width direction of the cover plate 10).

[0150] Of course, the positions of the two second connecting portions 22 are not limited to being located on both sides of the first connecting portion 21, as long as the two second connecting portions 22 are arranged along the first preset direction. In some other embodiments, the two second connecting portions 22 are located on the same side of the first connecting portion 21 in a second preset direction, which is consistent with the length direction of the cover plate 10. In this way, by setting the two second connecting portions 22 on the same side of the first connecting portion 21, the size of the pole post 20 in the width direction of the cover plate 10 is further reduced, so as to adapt to the narrower width of the cover plate 10.

[0151] The embodiment of the terminal post 20 being mounted on the cover plate 10 has been described above. However, the terminal post 20 is not limited to being mounted on the cover plate 10. In other embodiments, the terminal post 20 can also be mounted on the housing 200. Specifically, the battery cell 1 includes a housing 200, a cell assembly 300, the terminal post 20, and a first insulating member 30. The housing 200 has a receiving cavity and a first wall serving as one side wall of the receiving cavity. 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 penetrates the inner side and the outer side. The cell assembly 300 is received within the receiving cavity of the housing 200 and has at least two tabs 302 on the side facing the first wall. The terminal post 20 includes a first connecting portion 21 and at least two second connecting portions 22. The first connecting portion 21 is disposed on the outer side of the first wall, and each of the second connecting portions 22 is connected to the first connecting portion 21 and is arranged along the width direction of the first wall. Each second connecting portion 22 is at least partially inserted into the first through hole 11 and is connected to the corresponding tab 302. The first insulating member 30 includes a first insulating portion 31 disposed between the first connecting portion 21 and the first wall to form insulation.

[0152] It should be noted that the embodiment in which the pole post 20 is installed on the first wall of the housing 200 differs from the embodiment in which the pole post 20 is installed on the cover plate 10 only in the installation position of the pole post 20; the other structures are the same, so they will not be described in detail here.

[0153] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above 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.

[0154] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A top cover assembly, characterized in that, include: A cover plate (10) has 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) penetrates the first surface (a1) and the second surface (a2); and The pole post (20) includes at least one first connecting part (21) and at least two second connecting parts (22). The first connecting part (21) is located on the side of the cover plate (10) having the first surface (a1). Each of the second connecting parts (22) is connected to the first connecting part (21) and is arranged along a first preset direction. Each of the second connecting parts (22) is at least partially inserted into the first through hole (11) and is used to connect to the pole tab respectively.

2. The top cover assembly according to claim 1, characterized in that, On a dummy plane perpendicular to the thickness direction of the cover plate (10), the orthographic projection of the first connecting part (21) does not coincide with the orthographic projection of the first through hole (11), and the orthographic projection of the second connecting part (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 of the second connecting portions (22) includes 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) in a direction from the first surface (a1) to the second surface (a2) and forms a connecting sub-portion (223) passing through the first through hole (11).

4. The top cover assembly according to claim 3, characterized in that, The end of the connecting sub-part (223) away from the second region (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 includes a second insulating member (60), which is disposed on the second surface (a2) of the cover plate (10). The welding end (a3) ​​is disposed through the second insulating member (60), and the welding surface (a4) 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).

6. The top cover assembly according to claim 4, characterized in that, The welding end (a3) ​​protrudes from the second surface (a2) along the thickness direction of the cover plate (10) by a distance of 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 4, characterized in that, The top cover assembly also includes a first insulating member (30), which includes a first insulating portion (31) and a second insulating portion (34). The first insulating portion (31) is disposed between the first connecting portion (21) and the cover plate (10), and at least part 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 part (31) and the second insulating part (34) are integrally formed.

10. The top cover assembly according to claim 8, characterized in that, The connecting sub-part (223) has a first groove (225) on one end face that is 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 part (34) is recessed into 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 includes a first fixing part (40), which is connected to the first surface (a1) of the cover plate (10) and presses against the side of the second insulating part (34) away from the cover plate (10).

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

14. The top cover assembly according to claim 13, characterized in that, The first fixing part (40) includes a first arc segment (45), a straight edge segment (47), and a second arc segment (49) connected in sequence, 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 part (21); a clearance space (a5) is formed between the end of the first arc segment (45) away from the straight edge segment (47) and the 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 central angle of the first arc segment (45) is greater than 90°; and / or The central 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 the end of the second arc segment (49) away from the straight edge segment (47) and the first connecting part (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 part (40) includes a standing edge part (41) and a flange part (43). The standing edge part (41) is connected to the first surface (a1) of the cover plate (10). The flange part (43) is connected to the standing edge part (41) and is bent relative to the standing edge part (41) to the side of the second insulating part (34) away from the cover plate (10).

18. The top cover assembly according to claim 17, characterized in that, The flanged part (43) has an insulating gap (430) between the end of the flanged part (41) away from the upright part (41) and the second region (222), and part of the second insulating part (34) fills the insulating gap (430).

19. The top cover assembly according to claim 17, characterized in that, The second insulating portion (34) also covers the flanged portion and at least part of the upright portion; or The second insulating part (34) does not cover the standing edge part (41) and the flanged edge part (43).

20. The top cover assembly according to claim 17, characterized in that, The orthographic projection of the flanged part (43) on the cover plate (10) along the thickness direction is the first orthographic projection, and the orthographic projection of the second connecting part (22) on the cover plate (10) along the thickness direction is the second orthographic projection; the first orthographic projection and the second orthographic projection may or may not overlap.

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

22. The top cover assembly according to claim 21, characterized in that, Each of the second connecting portions (22) includes 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) in a direction from the first surface (a1) to the second surface (a2) and forms a connecting sub-portion (223) passing through the first through hole (11). Each of the transition portions (23) is provided with a second through hole (231). The top cover assembly also includes a first insulating member (30), which includes a second insulating portion (34) and a third insulating portion (32). At least a portion of the second insulating portion (34) covers the second region (222). The third insulating portion (32) fills the second through hole (231) and is connected to the second insulating portion (34).

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

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

25. The top cover assembly according to claim 24, characterized in that, The cover plate (10) has a first protrusion (13) on the first surface (a1) surrounding the first through hole (11), and the second sealing part (53) presses against the first protrusion (13).

26. The top cover assembly according to claim 24, characterized in that, The sealing ring (50) further includes a second protrusion (55), which protrudes from the second sealing portion (53) on the side opposite to the cover plate (10) and is arranged around the second region (222).

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

28. The top cover assembly according to claim 8, characterized in that, The first connecting part (21) has a second groove (210) on the side facing the cover plate (10), and part of the first insulating part (31) is filled in the second groove (210).

29. The top cover assembly according to claim 28, characterized in that, The second groove (210) gradually narrows or steps from the bottom to the opening.

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

31. The top cover assembly according to claim 8, characterized in that, The cover plate (10) has a third groove (12) on the surface facing the first connecting part (21), and part of the first insulating part (31) is filled in the third groove (12).

32. The top cover assembly according to claim 31, characterized in that, The third groove (12) gradually narrows or tapers from the bottom to the opening.

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

34. The top cover assembly according to claim 1 or 2, characterized in that, The first connecting part (21) has a boss (211) and an annular surface (213) on the side away from the cover plate (10). The annular surface (213) is arranged around the boss (211), and the boss (211) protrudes in a direction away from the cover plate (10) relative to the annular surface (213). The top cover assembly also includes a first insulating member (30), which includes a fourth insulating portion (35) arranged around the first connecting portion (21) and covering the peripheral edge of the first connecting portion (21).

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

36. A single battery cell, characterized in that, Includes a housing, a battery cell assembly, and a top cover assembly (100) as described in any one of claims 1 to 35; The housing has a receiving cavity and an opening communicating with the receiving cavity. The cover plate (10) is placed over the opening. The battery cell assembly is disposed in the receiving cavity and has at least two tabs on the side facing the cover plate (10). Each second connection part (22) extends through the first through hole (11) into the receiving cavity and is connected to the corresponding tab.

37. A single battery cell, characterized in that, include: The housing has a receiving cavity and a first wall serving as a side wall of the receiving cavity. The first wall has an inner side, an outer side, and a first through hole. The inner side faces the receiving cavity, the outer side faces away from the receiving cavity, and the first through hole penetrates the inner side and the outer side. A battery cell assembly, housed within the receiving cavity of the housing, and having at least two tabs on the side facing the first wall; and The pole post includes a first connecting part and at least two second connecting parts. The first connecting part is disposed on the outer side of the first wall. Each of the second connecting parts is connected to the first connecting part and is arranged along the width direction of the first wall. Each second connecting part is at least partially inserted into the first through hole and is respectively connected to the corresponding pole tab.

38. A battery, characterized in that, Includes the battery cell as described in claim 36 or 37.

39. An electrical appliance, characterized in that, It includes the battery cell as described in claim 36 or 37, or the battery as described in claim 38.

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