Battery cell cover plate and battery

Abstract

The invention relates to the technical field of batteries, and provides a battery cell cover plate and a battery, the battery cell cover plate comprises a cover plate body and a pole, the cover plate body comprises an outer surface and an inner surface opposite to each other, the cover plate body is provided with a protruding part extending from the inner surface to the outer surface, and the protruding part is provided with a through hole; an accommodating cavity with an opening facing the interior of the battery cell is formed in one side, close to the inner surface, of the lug boss; the pole penetrates through the cover plate body, and the height of the pole extending out of the outer surface of the cover plate body is lower than that of the lug boss. According to the battery cell cover plate provided by the invention, the convex part is arranged on the outer surface of the cover plate body, and the height of the top end of the pole is lower than that of the convex part, so that an effective physical protection mechanism is formed. When the battery is subjected to external impact or extrusion, the lug bosses can firstly contact and disperse external force, provide buffer protection for the pole columns, prevent the impact force from being transmitted to the pole groups in the battery cell through the pole columns, protect the structural stability of the pole groups, reduce the risks of pole group dislocation and internal short circuit caused by the external force, and improve the use safety and reliability of the battery.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more particularly to a cell cover and a battery. Background Technology

[0002] Lithium-ion batteries are widely used in various fields such as transportation power supply, power storage, new energy storage power supply, aerospace and military industry due to their advantages such as large capacity, high operating voltage, strong charge retention capability and long cycle life.

[0003] In existing technologies, the basic unit of a lithium-ion battery is the cell. The cell structure consists of an electrolyte, electrode assembly, bare cell insulating sheet, cover plate, cell casing, top patch, and outer insulating film. The cell casing and cover plate are welded together to form a closed space housing the electrode assembly. The cover plate includes a plain aluminum plate and integrated electrode posts, electrolyte injection holes, and explosion-proof structures. The outer periphery of the plain aluminum plate is welded and sealed to the cell casing. When cells are assembled into modules or battery packs, multiple cells are typically arranged side-by-side or stacked, and welded to the top of the electrode posts protruding from the plane of the plain aluminum plate via a busbar to achieve series and parallel connections between the cells.

[0004] However, when the upper part of the battery pack is impacted or squeezed by an external object, the external force will be transmitted to the electrode assembly inside the cell through the terminal post, which can easily cause internal structural misalignment, resulting in internal short circuit and posing a safety hazard. Summary of the Invention

[0005] This invention provides a cell cover and a battery to solve the defect of high internal short circuit risk in existing battery packs when subjected to external impact, effectively buffering and dispersing the external stress applied to the cell to enhance the impact resistance of the battery pack.

[0006] This invention provides a battery cell cover plate, comprising: The cover plate body includes an outer surface and an inner surface, and the cover plate body is provided with a protrusion extending from the inner surface to the outer surface. The side of the protrusion near the inner surface forms a receiving cavity with an opening facing the inside of the battery cell. The electrode post is inserted into the cover plate body, and the height of the electrode post extending beyond the outer surface of the cover plate body is lower than the height of the protrusion.

[0007] According to the present invention, a battery cell cover plate is provided, wherein the cover plate body is provided with mounting holes; the protrusion includes: A ring plate, one end of which is connected to the periphery of the mounting hole and extends outward from the cover plate body; A sealing plate is connected to the other end of the ring plate. The ring plate, the sealing plate, and the inner wall of the assembly hole form a receiving cavity, through which the connecting piece and the electrode are connected.

[0008] According to the present invention, a cell cover plate is provided, wherein the sealing plate is detachably connected to the other end of the ring plate.

[0009] According to the present invention, the height of the electrode post extending beyond the outer surface of the cover plate body is H1, and the height of the protrusion is H2, wherein H1 and H2 satisfy: 1.5 mm ≤ H2 - H1 ≤ 3.0 mm.

[0010] According to the present invention, the height of the protrusion is H2 and the thickness of the cover body is T, wherein H2 and T satisfy: H2 / T≤3.0.

[0011] According to the present invention, the thickness T of the cover body of the battery cell is in the range of 1.5 mm ≤ T ≤ 3 mm.

[0012] According to the present invention, the wall thickness t of the protrusion is in the range of 1.5 mm ≤ t ≤ 2 mm.

[0013] According to the present invention, a battery cell cover plate is provided at both ends of the cover plate body along the length direction, and there are two poles respectively disposed in the two pole holes; The cover plate body is provided with an explosion-proof valve hole in the middle; the cover plate body is provided with two protrusions, which are located on both sides of the explosion-proof valve hole and between the explosion-proof valve hole and the pole hole.

[0014] According to the present invention, the projected area of ​​the cover plate body along the thickness direction of the cover plate body is S, the projected area of ​​the protrusion along the thickness direction of the cover plate body is S1, the projected area of ​​the explosion-proof valve hole along the thickness direction of the cover plate body is S2, and the projected area of ​​the electrode post hole along the thickness direction of the cover plate body is S3. S, S1, S2, and S3 satisfy the following conditions: 0.3 ≤ (2S1 + S2 + 2S3) / S ≤ 0.5, and / or... The projected area S1 of the protrusion along the thickness direction of the cover plate body satisfies: 1.3F / 2S1 < R; where F is the external impact load and R is the yield strength of the cover plate body.

[0015] The present invention also provides a battery comprising: Battery cell casing; And a cell cover as described in any of the above, wherein the cell cover and the cell housing form a sealed space; The electrode assembly is located in the sealed space and is electrically connected to the cell cover plate.

[0016] The battery cell cover provided by this invention forms an effective physical protection mechanism by setting protrusions on the outer surface of the cover body and making the top of the terminal post lower than the protrusions. When the battery is subjected to external impact or pressure, the protrusions can make contact with and disperse the external force first, providing buffer protection for the terminal post, thereby preventing the impact force from being directly transmitted to the internal electrode assembly of the battery cell through the terminal post, effectively protecting the structural stability of the electrode assembly, reducing the risk of electrode misalignment and internal short circuit caused by external forces, and significantly improving the safety and reliability of the battery. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is one of the structural schematic diagrams of the battery provided by the present invention.

[0019] Figure 2 This is the second schematic diagram of the battery structure provided by the present invention.

[0020] Figure 3 This is one of the structural schematic diagrams of the battery cell cover plate provided by the present invention.

[0021] Figure 4 This is the second schematic diagram of the structure of the battery cell cover plate provided by the present invention.

[0022] Figure 5 This is the third schematic diagram of the structure of the battery cell cover plate provided by the present invention.

[0023] Figure 6 This is the fourth schematic diagram of the structure of the battery cell cover plate provided by the present invention.

[0024] Figure 7 This is a cross-sectional view of the battery cell cover plate provided by the present invention.

[0025] Figure 8 This is the third schematic diagram of the battery structure provided by the present invention.

[0026] Figure label: 100. Cell cover plate; 110. Cover plate body; 111. Protrusion; 1111. Ring plate; 1112. Sealing plate; 112. Receiving cavity; 113. Pole post hole; 114. Explosion-proof valve hole; 115. Liquid injection hole; 120. Pole column; 130. Connecting piece; 131. First connecting part; 132. Bending part; 133. Second connecting part; 200. Battery cell casing; 300, electrode group; 310, electrode tab. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0028] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention 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. Therefore, they should not be construed as limitations on the embodiments of the present invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention based on the specific circumstances.

[0030] In embodiments of the present invention, unless otherwise explicitly 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.

[0031] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0032] The following is combined with Figures 1-8 The present invention describes the cell cover plate and the battery.

[0033] An embodiment of the first aspect of the present invention provides a cell cover plate, such as Figure 3 As shown, the cell cover plate includes a cover plate body 110 and an electrode post 120 integrated on the cover plate body 110.

[0034] The cover plate body 110 includes an outer surface and an inner surface. The cover plate body 110 is provided with a protrusion 111 extending from the inner surface to the outer surface. The side of the protrusion 111 near the inner surface forms an opening facing the inside of the battery cell. The electrode post 120 passes through the cover plate body 110. The height of the electrode post 120 extending out of the outer surface of the cover plate body 110 is lower than the height of the protrusion 111.

[0035] It is understood that the cover plate body 110 has an outer surface and an inner surface that are arranged opposite to each other. The outer surface has an outward protrusion 111. The side of the protrusion 111 near the inner surface forms a receiving cavity. The pole post 120 is installed through the cover plate body 110. The top height of the pole post 120 extending out of the outer surface of the cover plate body 110 is set to be lower than the height of the protrusion 111, thereby forming an active protection zone composed of the protrusion 111 in the structure, providing effective buffer protection for the pole post 120.

[0036] like Figure 1 and Figure 2 As shown, the cell cover plate 100 is sealed to the cell housing 200. The outer surface of the cover plate body 110 is the side surface away from the inside of the cell housing 200, and the inner surface of the cover plate body 110 is the side surface close to the inside of the cell housing 200.

[0037] The battery cell cover provided in this embodiment of the invention forms an effective physical protection mechanism by providing a protrusion 111 on the outer surface of the cover body 110 and making the top of the terminal post 120 lower than the protrusion 111. When the battery is subjected to external impact or pressure, the protrusion 111 can make contact with and disperse the external force first, providing buffer protection for the terminal post 120, thereby preventing the impact force from being directly transmitted to the internal electrode assembly 300 of the battery cell through the terminal post 120, effectively protecting the structural stability of the electrode assembly 300, reducing the risk of misalignment and internal short circuit of the electrode assembly 300 caused by external force, and significantly improving the safety and reliability of the battery.

[0038] Furthermore, in existing technologies, the electrode assembly uses a side-mounted tab method, connecting the tab to the terminal post via a connecting piece. In actual production, to provide space for the tab connection, a certain gap H0 (e.g., 4 mm ~ 6 mm) is reserved between the inner surface of the cell cover and the lower electrode assembly, thus occupying internal cell space and affecting battery capacity. In contrast, this invention forms a receiving cavity with one open end at the protrusion 111, creating a connection channel between the connecting piece 130 and the tab 310. This allows the connection process between the tab 310 and the connecting piece 130 to occur within the internal space of the cell cover 100, saving space occupied within the cell, improving internal space utilization, and effectively increasing battery capacity.

[0039] Optional, such as Figure 3 , Figure 5 and Figure 7 As shown, the cover plate body 110 is provided with an assembly hole; the protrusion 111 includes an annular plate 1111 and a sealing plate 1112. One end of the annular plate 1111 is connected to the periphery of the assembly hole and extends outward from the cover plate body 110; the sealing plate 1112 is connected to the other end of the annular plate 1111. The annular plate 1111, the sealing plate 1112 and the inner wall of the assembly hole form a receiving cavity 112. The connecting piece 130 and the electrode 310 are connected through the receiving cavity 112, so the receiving cavity 112 serves as a connection channel between the connecting piece 130 and the electrode 310.

[0040] Understandably, the protrusion 111 adopts a hollow structure with one end open to form a receiving cavity 112 for the connecting piece 130 and the tab 310. This allows the welding process of the tab 310 and the connecting piece 130, which originally needed to be carried out in the space reserved below the cell cover 100, to be moved to the inside of the cell cover 100 itself. This saves space inside the cell, improves space utilization, and allows a larger capacity electrode assembly 300 to be accommodated in the cell housing 200 of the same size, effectively improving the energy density of the battery.

[0041] It should be noted that the terminal post 120 is inserted through and fixed to the cover plate body 110. The terminal post 120 includes a working end and a connecting end. The working end is used to connect with the external circuit of the battery and is the interface for realizing the external output of battery power. The connecting end is connected to the electrode tab 310 of the electrode group 300 through the connecting piece 130 and is the input end for collecting internal current. The working end of the terminal post 120 and the outer surface of the cover plate body 110 are located on the same side.

[0042] Furthermore, such as Figure 5 and Figure 7 As shown, the sealing plate 1112 is detachably connected to the other end of the ring plate 1111.

[0043] Understandably, during cell assembly, the sealing plate 1112 and the ring plate 1111 are separated to complete the welding operation of the internal connecting piece 130 and the tab 310, which provides more operating space and makes the process easier to implement. After welding, the sealing plate 1112 and the ring plate 1111 are then installed and fixed, which simplifies the assembly process, improves production efficiency, and provides convenience for subsequent maintenance or rework.

[0044] For example, the ring plate 1111 is a ring-shaped protrusion structure that is integrally formed with the cover plate body 110 through a molding process, and the two form a seamless whole.

[0045] In one embodiment of the present invention, multiple battery cells are connected to the upper surface of the terminal post 120 of each cell cover plate 100 via a busbar made of a metal sheet. The height of the protrusion 111 on the outer surface of the cover plate body 110 is slightly higher than the sum of the protrusion height of the terminal post 120 and the thickness of the metal sheet, thereby forming a certain gap between the upper surface of the metal sheet and the upper wall of the battery case. The space reserved in this gap is used to fill or apply thermally conductive structural adhesive to achieve efficient heat conduction and structural fixation.

[0046] Optional, such as Figure 4 As shown, the height of the pole post 120 extending beyond the outer surface of the cover plate body 110 is H1, and the height of the protrusion 111 is H2. H1 and H2 satisfy: 1.5 mm ≤ H2 - H1 ≤ 3.0 mm.

[0047] It should be noted that the height difference between H2 and H1 is not less than 1.5mm, ensuring that even if the protrusion 111 is subjected to an impact and undergoes a certain degree of elastic or plastic deformation, there is still sufficient buffer distance to prevent the impacting object from contacting the terminal post 120; the height difference between H2 and H1 is not greater than 3.0mm, avoiding excessive increase in the overall height of the cell due to the excessive height of the protrusion 111, which helps to achieve a compact design, thereby achieving an optimized balance between battery pack space utilization and structural design while ensuring safety.

[0048] In one embodiment of the present invention, such as Figure 4 As shown, the thickness T of the cover plate body 110 is in the range of 1.5mm≤T≤3mm.

[0049] Understandably, the thickness of the cover body 110, which serves as a platform for supporting components such as the terminal post 120 and the explosion-proof valve, directly affects the overall rigidity and strength of the cell cover 100. Designing the cover body 110 to be 1.5mm to 3mm thick can ensure that the cell cover 100 can withstand the internal pressure of the battery, external impact and assembly stress, while effectively controlling the weight of the parts and material costs, which helps to improve the overall mass energy density of the battery.

[0050] In one embodiment of the present invention, the height of the protrusion 111 is H2, and the thickness of the cover plate body 110 is T, wherein H2 and T satisfy: H2 / T≤3.0.

[0051] Understandably, by limiting the height of the protrusion 111 relative to the thickness of the cover plate body 110, it is possible to effectively prevent the protrusion 111 from shearing or buckling at the root due to an excessively large height-to-width ratio when subjected to lateral or top impacts, thus ensuring the effectiveness of the protrusion 111 as an energy-absorbing structure. Therefore, the ratio between the height of the protrusion 111 and the thickness of the cover plate body 110 is designed to be less than or equal to 3 to ensure the structural stability and strength of the protrusion 111 itself, while also ensuring that the part has good manufacturability and is easy to integrally form through processes such as stamping.

[0052] In one embodiment of the present invention, the wall thickness t of the protrusion 111 is in the range of 1.5 mm ≤ t ≤ 2 mm.

[0053] Understandably, the protrusion 111 is designed with an appropriate wall thickness to ensure that it can absorb a large amount of impact energy through its own plastic deformation when subjected to impact. This prevents it from being too rigid (too large a value for t) and transferring the force to the entire cell cover 100, or from being too thin (too small a value for t) and easily breaking and failing. Therefore, in this embodiment, the wall thickness t of the protrusion 111 is designed to be 1.5 mm ≤ t ≤ 2 mm, achieving the optimal balance between effectively absorbing energy and maintaining structural integrity, thus maximizing its buffering and protective effect.

[0054] In one embodiment of the present invention, the cover plate body 110 is a plain aluminum plate, the material of which is manganese aluminum alloy Al3003, wherein the AL element content is ≥98% and the Mn element content is ≥1%; the tensile strength of the cover plate body σ=145-195Mpa, the yield strength R≥125Mpa, the elongation δ≥3%, and the elastic modulus E=68-70Gpa.

[0055] In one embodiment of the present invention, such as Figure 3As shown, the cover plate body 110 is elongated, and pole post holes 113 are provided at both ends of the cover plate body 110 along the length direction; correspondingly, there are two pole posts 120, and the two pole posts 120 are respectively provided in the two pole post holes 113; an explosion-proof valve hole 114 is provided in the middle of the cover plate body 110, and the explosion-proof valve hole 114 is used to install an explosion-proof valve; the cover plate body 110 is provided with two protrusions 111, which are located on both sides of the explosion-proof valve hole 114 and between the explosion-proof valve hole 114 and the pole post hole 113.

[0056] It should be noted that the heat inside the battery cell can be directly conducted outwards not only through the thermally conductive structural adhesive above the terminal post 120, but also through the two protrusions 111, significantly enhancing the heat dissipation effect. Furthermore, the protrusions 111, located between the explosion-proof valve and the terminal post 120, can serve as a thermoelectric separator, improving the battery cell's safety performance.

[0057] It should be noted that in the prior art, the area between the two poles along the length of the cover plate body is not fully utilized. Furthermore, to ensure the welding operation between the tabs and the connecting piece, a certain height must be reserved between the cell cover plate and the lower electrode assembly. Both of these aspects lead to a waste of effective space inside the cell, restricting the increase in battery capacity. Based on this, the present invention arranges two protrusions 111 in the area between the two poles 120, transforming this space into an internal channel for connecting the tabs 310 and the connecting piece 130. This allows the welding process to be completed inside the cell cover plate 100, eliminating the need for a reserved height between the cell cover plate 100 and the electrode assembly 300, significantly improving the space utilization rate inside the cell, thereby effectively increasing the battery capacity within the same volume.

[0058] In this embodiment, a liquid injection hole 115 is provided on the sealing plate 1112. The liquid injection hole 115 serves as an electrolyte injection channel. After the cell cover plate is sealed, a certain amount of electrolyte is injected into the cell through the liquid injection hole. After the liquid injection is completed, the liquid injection hole is sealed with sealing steel balls and / or sealant to ensure that the inside of the cell is in a completely sealed state.

[0059] Optionally, the projected area of ​​the cover plate body 110 along the thickness direction of the cover plate body is S, the projected area of ​​the protrusion 111 along the thickness direction of the cover plate body is S1, the projected area of ​​the explosion-proof valve hole 114 along the thickness direction of the cover plate body is S2, and the projected area of ​​the pole hole 113 along the thickness direction of the cover plate body is S3. The relationship between S, S1, S2 and S3 satisfies: 0.3≤(2S1+S2+2S3) / S≤0.5.

[0060] It is understandable that by limiting the proportion of the total area of ​​the openings (2S1+S2+2S3) to the total area of ​​the cover plate body 110, it is ensured that while meeting functional requirements, the overall structural strength of the cell cover plate 100 is not excessively weakened, and sufficient load-bearing material is retained to ensure the overall rigidity and sealing reliability of the cover plate.

[0061] For example, the cover plate body 110 is long and narrow, with a length of L and a width of W. The values ​​of L and W are: 150≤L≤300, 25≤W≤75; S1=L×W.

[0062] The cross-section of the protrusion 111 is quadrilateral, with a length of L1 and a width of W1, and S1 = L1 × W1. It should be noted that the protrusion 111 can be a frustum of a cone with its large end connected to the cover plate body 110 and its small end away from the cover plate body 110, and the projected area S1 is the cross-sectional area of ​​the smallest end (small end).

[0063] Optionally, when the battery is impacted in the Z direction (thickness direction of the cover plate body 110), the force acting on the protrusion 111 is F. To ensure sufficient strength for the protrusion 111, the projected area S1 of the protrusion 111 along the thickness direction of the cover plate body satisfies: 1.3F / 2S1 < R; where F is the external impact load in Newtons (N); and S1 is the projected area of ​​a protrusion 111 in square millimeters (mm). 2 R is the yield strength of the cover plate body 110, in megapascals (MPa).

[0064] Understandably, from the perspective of materials mechanics, this provides an engineering design basis for the impact resistance of the protrusion 111. By introducing a safety factor of 1.3, it is ensured that under the action of external impact load F, the stress borne by the two protrusions 111 is much less than the yield strength R of the material, thereby ensuring that the protrusion 111 and the cover plate body 110 can effectively withstand the impact without failure, play a good supporting role, and improve the safety performance of the battery cell.

[0065] In some embodiments of the present invention, in order to verify the feasibility of the above-mentioned cell cover structure design, multiple embodiments (Examples 1 to 10) and multiple comparative examples (Comparative Examples 1 to 3) of cell cover plate samples were designed, and their specific design parameters are shown in Table 1; and the mechanical response of the cell cover plate under a Z-direction mechanical impact of magnitude F was simulated by performing battery pack (PACK) level simulation analysis on each sample.

[0066] Table 1

[0067] The simulation results show that when the conditions 0.3 ≤ (2S1 + S2 + 2S3) / S ≤ 0.5 and 1.3F / (2S1) < R are satisfied, the stress values on the outer surface of the convex portion 111 and the cover plate body 110 of Embodiments 1 to Embodiment 10 do not show a significant increase, indicating that the structure does not undergo significant deformation under impact and its strength meets the design requirements.

[0068] In contrast, the stress values on the outer surface of the convex portion 111 of Comparative Examples 1 to Comparative Example 3 increase by approximately 4.5%, 5.5%, and 5.1% respectively. Analysis shows that when the overall area of the convex portion 111 is insufficient, resulting in 1.3F / (2S1) > R, the stress on the surface material of the convex portion 111 exceeds its yield strength and cannot meet the stress requirements; when the ratio of (2S1 + S2 + 2S3) / S is too large, the overall strength of the cover plate body 110 decreases due to the excessive opening area, which also causes the surface stress to rise, not meeting the structural safety requirements.

[0069] In an embodiment of the present invention, as Figures 5 to 7 shown, a connecting piece 130 is provided on the inner surface of the cover plate body 110. The number of connecting pieces 130 is the same as the number of pole columns 120, and the positions correspond one by one. One end of the connecting piece 130 is connected to the connecting end of the pole column 120, and the other end of the connecting piece 130 faces the corresponding position of the assembly hole. The assembly hole serves as a channel for connecting the other end of the connecting piece 130 and the pole ear 310. After the connection between the other end of the connecting piece 130 and the pole ear 310 is completed, a sealing plate 1112 is provided on the ring plate 1111.

[0070] Optionally, the connecting piece 130 includes a first connecting portion 131, a bending portion 132, and a second connecting portion 133 connected in sequence. The first connecting portion 131 is connected to the pole column 120, and the bending portion 132 extends toward the sealing plate 1112, so that the second connecting portion 133 is disposed in the receiving cavity 112. The second connecting portion 133 is used to connect to the pole ear 310. Thus, the second connecting portion 133 faces away from the internal space of the battery, and the connection process between the pole ear 310 and the second connecting portion 133 is completed inside the internal space of the battery cell cover 100, effectively saving the occupied space inside the battery cell and thus increasing the battery capacity.

[0071] Exemplarily, the first connecting portion 131 and the second connecting portion 133 are arranged along the plane direction of the cover plate body 110.

[0072] It can be understood that the first connecting portion 131 extends along the plane direction (horizontal direction) of the cover plate body 110 after being led out from the pole column 120. After the second connecting portion 133 turns through the intermediate bending portion 132, it also extends along the horizontal direction and extends into the convex portion 111.

[0073] It should be noted that as Figure 8 As shown, the tab 310 is vertically assembled and passes between the side of the second connecting part 133 and the side wall of the receiving cavity 112. The tab area extending above the second connecting part 133 (referred to as the tab connecting part) is bent and attached to the upper surface of the second connecting part 133. The upper surface of the second connecting part 133 and the tab connecting part are welded together, thereby completing the connection between the connecting piece 130 and the tab 310 within the receiving cavity 112.

[0074] A second aspect of the present invention provides a battery, such as Figure 1 and Figure 2 As shown, the battery includes a cell housing 200, an electrode assembly 300, and a cell cover plate 100 provided in any of the above embodiments. The cell cover plate 100 and the cell housing 200 form a closed space. The electrode assembly 300 is disposed in the closed space and is electrically connected to the cell cover plate 100.

[0075] It is understood that by employing the cell cover 100 of any of the above embodiments, the battery provided by the present invention possesses the various advantages of the cell cover 100 as described above. Therefore, the battery has significantly enhanced resistance to external mechanical shock and compression, effectively preventing internal short circuits caused by external forces, thereby greatly improving the battery's safety and reliability. Simultaneously, the space optimization brought about by the cell cover 100 also results in higher energy density, significantly improving overall performance.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery cell cover plate, characterized in that, include: The cover plate body includes an outer surface and an inner surface, and the cover plate body is provided with a protrusion extending from the inner surface to the outer surface. The side of the protrusion near the inner surface forms a receiving cavity with an opening facing the inside of the battery cell. The electrode post is inserted into the cover plate body, and the height of the electrode post extending beyond the outer surface of the cover plate body is lower than the height of the protrusion.

2. The cell cover plate according to claim 1, characterized in that, The cover plate body is provided with mounting holes; the protrusion includes: A ring plate, one end of which is connected to the periphery of the mounting hole and extends outward from the cover plate body; A sealing plate is connected to the other end of the ring plate. The ring plate, the sealing plate, and the inner wall of the assembly hole form the receiving cavity. The connecting piece and the electrode are connected through the receiving cavity.

3. The cell cover plate according to claim 2, characterized in that, The sealing plate is detachably connected to the other end of the ring plate.

4. The cell cover plate according to claim 1, characterized in that, The height of the pole extending beyond the outer surface of the cover plate body is H1, and the height of the protrusion is H2. H1 and H2 satisfy: 1.5 mm ≤ H2 - H1 ≤ 3.0 mm.

5. The cell cover plate according to claim 1, characterized in that, The height of the protrusion is H2, and the thickness of the cover plate body is T. H2 and T satisfy: H2 / T≤3.

0.

6. The cell cover plate according to claim 5, characterized in that, The thickness T of the cover plate body is in the range of 1.5 mm ≤ T ≤ 3 mm.

7. The cell cover plate according to claim 1, characterized in that, The wall thickness t of the protrusion is in the range of 1.5 mm ≤ t ≤ 2 mm.

8. The cell cover plate according to any one of claims 1 to 7, characterized in that, The cover plate body is provided with pole holes at both ends along the length direction, and there are two poles, which are respectively provided in the two pole holes; The cover plate body is provided with an explosion-proof valve hole in the middle; the cover plate body is provided with two protrusions, which are located on both sides of the explosion-proof valve hole and between the explosion-proof valve hole and the pole hole.

9. The cell cover plate according to claim 8, characterized in that, The projected area of ​​the cover plate body along the thickness direction is S, the projected area of ​​the protrusion along the thickness direction is S1, the projected area of ​​the explosion-proof valve hole along the thickness direction is S2, and the projected area of ​​the pole hole along the thickness direction is S3. S, S1, S2, and S3 satisfy the following conditions: 0.3 ≤ (2S1 + S2 + 2S3) / S ≤ 0.5, and / or... The projected area S1 of the protrusion along the thickness direction of the cover plate body satisfies: 1.3F / 2S1 < R; where F is the external impact load and R is the yield strength of the cover plate body.

10. A battery, characterized in that, include: Battery cell casing; And the cell cover plate as described in any one of claims 1 to 9, wherein the cell cover plate and the cell housing form a sealed space; The electrode assembly is located in the sealed space and is electrically connected to the cell cover plate.

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