Battery cell cover plate and battery cell

Abstract

The application relates to the battery technical field and provides a battery cell cover plate and a battery cell, the battery cell cover plate comprises a cover plate body, the cover plate body comprises a base plate, a supporting table and a mounting table, the supporting table and the mounting table are arranged on the same side of the base plate along the thickness direction of the base plate and are arranged along the length direction of the base plate, the cover plate body is provided with a through hole penetrating through the mounting table; a pole is arranged in the through hole and protrudes from the mounting table; in the thickness direction, the height of the supporting table relative to the base plate is greater than the height of one end of the pole protruding from the mounting table relative to the base plate. The battery cell cover plate can be supported and connected with the box body of a battery pack through the supporting table, the shell of the battery cell itself is used as a supporting force piece, the utilization rate of the internal space of the battery pack is improved, and the structural strength of the cover plate body corresponding to the pole area is increased through the mounting table.

Description

Technical Field

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

[0002] The battery pack includes a casing and battery modules assembled inside the casing. Each battery module consists of multiple cells, with the terminals of these cells electrically connected via busbars. The casing provides physical support for the battery modules, protecting them from external impacts and pressure, while also preventing the intrusion of moisture, dust, and other impurities. As users' demands for longer battery life continue to increase, current battery technology faces a contradiction: battery capacity development lags behind market demand, leading to user range anxiety.

[0003] In traditional battery pack structures, to prevent the busbars and terminals from being squeezed when the casing deforms under external impact, a large space is left between the busbars and the battery pack casing. However, this results in low utilization of the internal space of the battery pack, which is not conducive to improving the energy density of the battery pack. Summary of the Invention

[0004] This invention provides a cell cover and a cell to solve the problem of low internal space utilization in battery packs in the prior art.

[0005] This invention provides a battery cell cover plate, comprising: The cover plate body includes a base plate, a support platform and a mounting platform. The support platform and the mounting platform protrude from the same side of the base plate along the thickness direction of the base plate and are arranged along the length direction of the base plate. The cover plate body is provided with a through hole penetrating the mounting platform. The pole post passes through the through hole and protrudes from the mounting platform. In the thickness direction, the height of the support platform relative to the substrate is greater than the height of the end of the pole post protruding from the mounting platform relative to the substrate.

[0006] According to the present invention, a battery cell cover plate is provided in which the support platform and the mounting platform are connected to form a stepped boss.

[0007] A cell cover plate provided by the present invention further includes: An explosion-proof valve is disposed on the base plate. There are two support platforms and two mounting platforms. In the length direction, the two support platforms are disposed on both sides of the explosion-proof valve, and the two mounting platforms are disposed on both sides of the explosion-proof valve. The support platform is located between the explosion-proof valve and the mounting platform.

[0008] According to a battery cell cover provided by the present invention, a first groove is formed on the side of the cover body away from the support platform corresponding to the position of the support platform, and / or a second groove is formed on the side of the cover body away from the support platform corresponding to the position of the mounting platform.

[0009] A cell cover plate provided by the present invention further includes: An insulating element is disposed on the side of the substrate away from the support platform. The pole passes through the insulating element. A protrusion is formed on the side of the insulating element near the cover plate body. The first groove and the second groove are connected to form a stepped groove. The protrusion is located in the stepped groove. A stepped groove is formed on the side of the insulating element away from the substrate corresponding to the position of the protrusion.

[0010] A cell cover plate provided by the present invention further includes: A connecting piece is located within the stepped groove. A portion of the connecting piece is connected to the pole post, and another portion is opposite to the support platform in the thickness direction and is adapted to connect to the pole lug of the pole assembly.

[0011] According to the present invention, the side wall of the support platform is at an angle of 90°+β to the substrate, and the side wall of the mounting platform is at an angle of 90°+γ to the substrate, wherein 15°≤β≤25° and 15°≤γ≤25°.

[0012] According to a battery cell cover plate provided by the present invention, the base plate is provided with a mounting groove for setting an explosion-proof valve, and in the length direction, the support platform is located between the mounting groove and the mounting platform, and the distance between the support platform and the mounting groove is G1, where G1≥3mm; And / or, the cell cover plate further includes an upper plastic, the top of the mounting platform is provided with a positioning groove, the upper plastic is disposed in the positioning groove, the electrode post passes through the upper plastic, the support platform and the mounting platform are connected to form a stepped boss, the distance between the positioning groove and the edge of the mounting platform in the length direction is G2, the distance between the positioning groove and the edge of the mounting platform in the width direction of the substrate is G3, 3mm≤G2≤6mm, 3mm≤G3≤7mm; And / or, in the width direction of the substrate, the distance between the support platform and the mounting platform and the edge of the substrate is G4, where 3mm≤G4≤7mm.

[0013] According to the present invention, the height of the mounting platform relative to the substrate in the thickness direction is H1, where 1.0mm≤H1≤2mm; And / or, the height of the support platform relative to the pole in the thickness direction is H2, 1.5mm≤H2≤2.5mm.

[0014] The present invention also provides a battery cell, comprising: The battery cell casing has an opening; In any of the above-mentioned cell cover plates, the cell cover plate is disposed in the opening and surrounds the cell housing to form a receiving cavity; An electrode assembly is disposed within the receiving cavity, and the electrode tabs of the electrode assembly are connected to the electrode post.

[0015] The present invention provides a cell cover and a cell. By setting a support platform on the cover body and using the support platform to support and connect with the battery pack housing, the outer shell of the cell itself also serves as a supporting load-bearing component. This avoids large deformation of the housing, helps reduce the thickness of the housing, and enables a lightweight design of the battery pack. Furthermore, while ensuring that the housing does not cause crush damage to the busbars and terminals, it reduces the distance between the busbars and the housing, thereby increasing the volume of the cell, fully utilizing the internal space of the housing, and improving the capacity of the cell and the energy density of the entire battery pack. The heat of the cell can be transferred to the housing through the support platform, improving the heat dissipation efficiency of the cell. Simultaneously, by setting a mounting platform on the cover body, the structural strength of the area corresponding to the terminals on the cover body is increased, reducing the risk of short circuits caused by deformation of the cover body under impact forces that could crush the terminals. Attached Figure Description

[0016] 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.

[0017] Figure 1 This is one of the structural schematic diagrams of the battery cell cover plate provided by the present invention.

[0018] Figure 2 yes Figure 1 A schematic diagram of the battery cell cover from another perspective.

[0019] Figure 3 yes Figure 1 Side view of the cell cover plate.

[0020] Figure 4 yes Figure 1 A top view of the battery cell cover plate.

[0021] Figure 5 yes Figure 4 A partial cross-sectional view of the battery cell cover plate at point AA.

[0022] Figure 6This is the second schematic diagram of the structure of the battery cell cover plate provided by the present invention.

[0023] Figure 7 yes Figure 6 A top view of the battery cell cover plate.

[0024] Figure 8 yes Figure 6 Side view of the cell cover plate.

[0025] Figure 9 yes Figure 6 Exploded view of the battery cell cover plate.

[0026] Figure 10 This is a schematic diagram of the plastic component structure in the battery cell cover provided by the present invention.

[0027] Figure 11 This is an exploded view of a portion of the structure of the battery cell cover plate provided by the present invention.

[0028] Figure 12 yes Figure 7 A partial cross-sectional view of the cell cover plate at BB.

[0029] Figure 13 This is a schematic diagram of the battery cell provided by the present invention.

[0030] Figure label: 1. Cover plate body; 11. Base plate; 111. Mounting groove; 12. Stepped boss; 121. Support platform; 1211. Injection hole; 122. Mounting platform; 1221. Positioning groove; 2. Pole post; 21. Connecting post; 22. Riveting block; 3. Explosion-proof valve; 4. Insulating component; 41. Protrusion; 42. Stepped recess; 43. Exhaust structure; 5. Connecting piece; 51. Welding part; 52. Base part; 53. Connecting part; 6. Top plastic; 7. Protective component; 71. Patch 710. Through hole; 711. Adhesive part; 712. Separation part; 713. Scoring line; 714. Reserved hole; 72. Plastic part; 721. Enclosure part; 722. Covering part; 7221. First frame part; 7222. Second frame part; 7231. First window; 7232. Second window; 724. Avoidance notch; 7241. First notch; 7242. Second notch; 731. First adhesive layer; 732. Second adhesive layer; 74. Separator; 8. Battery cell housing. Detailed Implementation

[0031] 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.

[0032] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "first" and "second" are numbered for the purpose of clearly identifying product components and do not represent any substantial difference. The terms "installed," "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 direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances. Furthermore, "multiple" means two or more. In the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following related objects are in an "or" relationship.

[0033] The following is combined with Figures 1-13 The present invention describes the cell cover plate and the cell.

[0034] like Figure 1 As shown, the battery cell cover plate provided in this embodiment of the invention includes a cover plate body 1 and an electrode post 2. The cover plate body 1 includes a substrate 11, a support platform 121, and a mounting platform 122. The support platform 121 and the mounting platform 122 protrude from the same side of the substrate 11 along the thickness direction and are arranged along the length direction of the substrate 11. The cover plate body 1 has a through hole penetrating the mounting platform 122. The electrode post 2 passes through the through hole and protrudes from the mounting platform 122. In the thickness direction of the substrate 11, the height of the support platform 121 relative to the substrate 11 is greater than the height of the end of the electrode post 2 protruding from the mounting platform 122 relative to the substrate 11.

[0035] This cell cover is applied to the battery cell, which includes a cell housing 8, electrode assembly, and cell cover. The cell housing has an opening, and the cell cover is positioned at the opening and surrounds the cell housing to form a receiving cavity. The electrode assembly is disposed within the receiving cavity. The cell housing and cover body 1 are welded together to form the outer shell of the battery cell, providing protection for the internal components and withstanding certain external impacts. A terminal post 2 protrudes from the outer surface of the cover body 1 to form a terminal terminal, used for connection to a busbar, allowing multiple cells to be connected via the busbar to form a battery module. The other end of the terminal post 2 is located within the receiving cavity and connected to the electrode tab of the electrode assembly. The battery module is assembled into a housing to form a battery pack.

[0036] See the length and width directions of substrate 11. Figure 1 The thickness direction of the substrate 11 is perpendicular to the length and width directions. Specifically, the cover plate body 1 has a first side and a second side opposite to each other in the thickness direction of the substrate 11. The first side faces the outside of the cell and is provided with a support platform 121 and a mounting platform 122. The electrode post 2 protrudes from one end of the mounting platform 122 to form an electrode post terminal. The second side faces the electrode group inside the receiving cavity.

[0037] The support platform 121 is adapted to be connected to the battery pack housing for support. When the battery pack is in use, the support platform 121 can be located on the top or side of the battery cell and abut against the housing to withstand the impact force transmitted from the housing. The part of the housing that is supported and connected to the support platform 121 can be the housing shell; alternatively, the housing includes a shell and a cold plate, with the cold plate located between the shell and the battery cell, and the support platform 121 supported and connected to the cold plate. The height of the support platform 121 relative to the surface of the substrate 11 is greater than the height of the end of the terminal post 2 protruding from the mounting platform 122 relative to the surface of the substrate 11, so that a certain space is reserved between the terminal post 2 and the housing for the installation of a busbar.

[0038] In traditional battery pack structures, the battery pack relies solely on the casing to withstand external impacts. However, the casing plate opposite the terminal 2 has a large area, making it prone to deformation if its rigidity is insufficient. To prevent casing deformation from causing compression damage to the busbar and terminal 2, a large space needs to be reserved between the busbar and the casing in the structural design, with supporting foam installed between them. Some designs also incorporate concave and convex structures on the casing plate to enhance rigidity and prevent deformation. However, these measures result in a large gap between the cells and the casing, wasting space. Increasing the casing thickness to increase rigidity would increase the weight of the battery pack, hindering lightweight design. Furthermore, the heat from the cell cover is dissipated only through conduction between the terminal 2 and the busbar, and through its own thermal radiation, resulting in low heat dissipation efficiency and easy heat accumulation.

[0039] To address this, this embodiment includes a support platform 121 on the cover plate body 1. The support platform 121 is connected to the casing for support, allowing the outer shell of the battery cell itself to also serve as a load-bearing component. Under the support of the outer shell, significant deformation of the casing can be avoided, thereby reducing the casing thickness and the weight of the battery pack. Furthermore, while ensuring that the casing does not cause crush damage to the busbars and terminals 2, the distance between the busbars and the casing can be reduced, thereby increasing the volume of the battery cell. This fully utilizes the internal space of the casing, improving the capacity of the battery cell and the energy density of the entire battery pack.

[0040] Furthermore, a mounting platform 122 is provided on the cover plate body 1, through which the pole post 2 passes. The mounting platform 122 strengthens the structure of the area on the cover plate body 1 corresponding to the pole post 2, reducing the risk of short circuit caused by deformation of this area under impact force, which could compress the pole post 2.

[0041] It should be noted that the battery cell has two terminals 2, namely a positive terminal and a negative terminal. In this embodiment of the invention, the number of terminals 2 on the battery cell cover can be one or two. The number of mounting platforms 122 can be determined based on the number of terminals 2, with each terminal 2 corresponding to one mounting platform 122.

[0042] The cell cover provided in this embodiment of the invention, by setting a support platform 121 on the cover body 1, utilizes the support platform 121 to support and connect with the battery pack housing, so that the outer shell of the cell itself also serves as a supporting load-bearing component. This avoids large deformation of the housing, helps reduce the thickness of the housing, and achieves a lightweight design for the battery pack. Furthermore, while ensuring that the housing does not cause crush damage to the busbars and terminals 2, it reduces the distance between the busbars and the housing, thereby increasing the volume of the cell, fully utilizing the internal space of the housing, and improving the capacity of the cell and the energy density of the entire battery pack. The heat from the cell can be transferred to the housing through the support platform 121, improving the heat dissipation efficiency of the cell. Simultaneously, by setting a mounting platform 122 on the cover body 1, the structural strength of the area corresponding to the terminals 2 on the cover body 1 is increased, reducing the risk of short circuits caused by the deformation of the cover body 1 under impact forces that could crush the terminals 2.

[0043] In traditional battery cell cover structures, the electrolyte injection hole 1211 is located on the substrate 11, the electrode post 2 passes through the substrate 11, and a protective patch is attached to the outer surface of the cover body 1. The protective patch has holes to avoid the electrode post 2. During electrolyte injection, the pumped electrolyte can easily flow from the holes into the mating gap between the electrode post 2 and the cover body 1, as well as between the protective patch and the cover body 1, damaging the sealing of the battery cell cover, causing abnormal voltage, corroding the cover body 1, and affecting the safety performance of the battery cell. This embodiment of the invention also utilizes the mounting platform 122 to prevent electrolyte from flowing into the mating gap between the electrode post 2 and the cover body 1, thus preventing sealing failure and abnormal voltage.

[0044] In some embodiments of the present invention, the support platform 121 and the mounting platform 122 are connected to form a stepped boss 12. It is understood that the height of the support platform 121 relative to the substrate 11 is greater than the height of the mounting platform 122 relative to the substrate 11, and the two are connected to form an integral stepped boss 12, which saves the plate surface space of the cover plate body 1.

[0045] It should be noted that, if there is sufficient space on the surface of the cover plate body 1, the support platform 121 and the mounting platform 122 can also be set at intervals.

[0046] like Figure 1 As shown, the battery cell cover provided in this embodiment of the invention also includes an explosion-proof valve 3. The explosion-proof valve 3 is disposed on the substrate 11. Specifically, the substrate 11 is provided with an exhaust port, which communicates with the housing cavity of the battery cell, and the explosion-proof valve 3 is opposite to the exhaust port. When the battery cell experiences thermal runaway, the high-temperature gas inside can be discharged from the explosion-proof valve 3.

[0047] The explosion-proof valve 3 is located on the side of the support platform 121 away from the mounting platform 122, thus separating the terminal post 2 and the explosion-proof valve 3. The support platform 121 can be used to prevent the high-temperature gas and liquid discharged from the explosion-proof valve 3 from reaching the terminal post 2 and the busbar, achieving thermoelectric isolation and improving the safety performance of the battery pack.

[0048] Optionally, such as Figure 1 and Figure 3 As shown, there are two support platforms 121 and two mounting platforms 122. Along the length of the base plate 11, two support platforms 121 are positioned on either side of the explosion-proof valve 3, and two mounting platforms 122 are positioned on either side of the explosion-proof valve 3. The support platforms 121 are located between the explosion-proof valve 3 and the mounting platforms 122. Two pole posts 2 are correspondingly inserted through the two mounting platforms 122. A support platform 121 is provided between each pole post 2 and the explosion-proof valve 3, separating the two pole posts 2 from the explosion-proof valve 3.

[0049] Optionally, along the length of the substrate 11, two stepped bosses 12 are symmetrically distributed on both sides of the explosion-proof valve 3. Two support platforms 121 of the two stepped bosses 12 separate the pole posts 2 and the explosion-proof valve 3 on the two mounting platforms 122.

[0050] In this embodiment of the invention, the support platform 121, the mounting platform 122, and the substrate 11 are integrally formed; or, the support platform 121 and the mounting platform 122 are each independent structural components, or the stepped boss 12 formed by the two is connected and welded to the substrate 11 as an integral structural component, thereby forming the cover plate body 1. The support platform 121 and the mounting platform 122 may be solid structures; or, the support platform 121 and the mounting platform 122 may be hollow structures, that is, the support platform 121 and the mounting platform 122 form a groove on the side facing the receiving cavity, which can reduce the weight of the cover plate body 1 and improve the structural strength of the cover plate body 1.

[0051] Optionally, the support platform 121 and the mounting platform 122 are formed by stamping from sheet metal. For example, the support platform 121 and the mounting platform 122 are each formed by stamping from separate sheet metal and then welded to the substrate 11. Alternatively, the support platform 121, the mounting platform 122, and the substrate 11 are integrally formed by stamping from the same sheet metal.

[0052] When the support platform 121 and mounting platform 122 are hollow internal structures, optionally, a first groove is formed on the side of the cover plate body 1 away from the support platform 121, corresponding to the position of the support platform 121, and / or, a second groove is formed on the side of the cover plate body 1 away from the support platform 121, corresponding to the position of the mounting platform 122. In this embodiment, forming a first groove on the support platform 121 and / or a second groove on the mounting platform 122 facilitates expanding the internal space of the battery cell, increasing the volume of the electrode assembly inside the battery cell, and thus increasing the capacity of the battery cell.

[0053] When the support platform 121 and the mounting platform 122 are connected to form a stepped boss 12, the first groove and the second groove are connected to form a stepped groove.

[0054] like Figure 2 and Figure 5 As shown, the battery cell cover provided in some embodiments of the present invention also includes an insulating member 4. The insulating member 4 is disposed on the side of the substrate 11 away from the support platform 121, and the electrode post 2 passes through the insulating member 4. The insulating member 4 is provided with an exhaust structure 43 opposite to the exhaust hole on the cover body 1. The exhaust structure 43 may be composed of multiple through holes to ensure the normal exhaust of the explosion-proof valve 3 while ensuring the structural strength of the insulating member 4.

[0055] When the cell cover is installed on the cell housing, the insulating component 4 is located between the cover body 1 and the electrode group, serving as insulation between the cover body 1 and the electrode group. The electrode post 2 passes through both the cover body 1 and the insulating component 4, with one end of the electrode post 2 located on the side of the insulating component 4 away from the cover body 1, for connection with the electrode tab of the electrode group.

[0056] In some embodiments of the present invention, a protrusion 41 is formed on the side of the insulating member 4 near the cover plate body 1. A first groove and a second groove are connected to form a stepped groove, and the protrusion 41 is located in the stepped groove. A stepped recess 42 is formed on the side of the insulating member 4 away from the substrate 11 corresponding to the position of the protrusion 41. The stepped recess 42 can be used to accommodate the tabs of the electrode assembly.

[0057] It is understandable that the insulating component 4 forms a stepped protrusion 41 on the side near the cover plate body 1. The stepped protrusion 41 and the stepped groove of the cover plate body 1 are in concave-convex fit to make full use of the internal space of the support platform 121 and the mounting platform 122 and increase the accommodating space of the stepped groove 42.

[0058] In the cell structure, the stepped groove 42 and the electrode group define the space for accommodating the electrode tabs, allowing for a larger space inside the cell to house the electrode group body, increasing the space utilization rate inside the cell casing, and thus further increasing the cell capacity.

[0059] like Figure 5As shown, some embodiments of the present invention provide a cell cover plate that also includes a connecting piece 5. The connecting piece 5 is located within a stepped recess 42. A portion of the connecting piece 5 is connected to the electrode post 2, and another portion is opposite to the support platform 121 in the thickness direction and is adapted to be connected to the electrode tab of the electrode assembly. The fact that the connecting piece 5 is located within the stepped recess 42 further improves the space utilization rate inside the cell casing, which is beneficial for increasing the cell capacity.

[0060] Specifically, the connecting piece 5 includes a welding portion 51, a connecting portion 53, and a base portion 52 that are sequentially connected along the length of the substrate 11. The welding portion 51 is used to connect with the electrode tab and corresponds to the area of ​​the first groove, the base portion 52 is connected with the electrode post 2 and corresponds to the area of ​​the second groove, and the welding portion 51 is parallel to the base portion 52 and is set at an angle to the connecting portion 53.

[0061] like Figure 5 As shown, in some embodiments of the present invention, the angle between the side wall of the support platform 121 and the substrate 11 is 90°+β, and the angle between the side wall of the mounting platform 122 and the substrate 11 is 90°+γ, 15°≤β≤25°, and 15°≤γ≤25°.

[0062] Both the support platform 121 and the mounting platform 122 have a top wall and side walls connected to the top wall. Setting the angles to 15°≤β≤25° and 15°≤γ≤25° helps ensure the manufacturability, structural strength, and uniform stress distribution of the support platform 121 and the mounting platform 122, thereby improving production yield. If the included angle is too small, it is not conducive to the stamping process and easily causes significant stress concentration; if the included angle is too large, the impact resistance is insufficient, and the support platform 121 and the mounting platform 122 occupy a large area, which is not conducive to the distribution of the support platform 121, the mounting platform 122, and the explosion-proof valve 3.

[0063] like Figure 1 and Figure 4 As shown, in this embodiment of the invention, the substrate 11 is provided with a mounting groove 111 for mounting the explosion-proof valve 3.

[0064] The vent is located within the mounting groove 111. After the explosion-proof valve 3 is installed in the mounting groove 111, it is opposite to the vent. The mounting groove 111 serves to position the explosion-proof valve 3. When the mounting groove 111 is deep enough, the upper surface of the explosion-proof valve 3 can be lower than the surface of the base plate 11, preventing the explosion-proof valve 3 from being damaged by impact during production or handling, thus preventing the explosion-proof valve 3 from failing.

[0065] Furthermore, along the length of the substrate 11, the support platform 121 is located between the mounting groove 111 and the mounting platform 122, and the distance between the support platform 121 and the mounting groove 111 is G1, where G1 ≥ 3 mm. It is understood that the support platform 121 is located between the explosion-proof valve 3 and the pole post 2 to achieve thermoelectric isolation.

[0066] When both the support platform 121 and the mounting groove 111 are formed by stamping, if the distance between the support platform 121 and the mounting groove 111 is too small, the mounting groove 111 is prone to deformation. In this embodiment, by setting the distance between the support platform 121 and the mounting groove 111 to G1≥3mm, the stamping yield of the support platform 121 and the mounting groove 111 can be improved, deformation of the mounting groove 111 can be avoided, and the assembly yield of the explosion-proof valve 3 and the cover plate body 1 can be improved.

[0067] like Figure 1 and Figure 4 As shown, the battery cell cover provided in this embodiment of the invention also includes an upper plastic 6. The top of the mounting platform 122 is provided with a positioning groove 1221. The upper plastic 6 is disposed in the positioning groove 1221, and the electrode post 2 passes through the upper plastic 6.

[0068] Specifically, the through hole on the mounting platform 122 for inserting the pole post 2 is located within the positioning groove 1221. For example... Figure 12 As shown, the pole post 2 includes a connecting post 21 and a rivet block 22. The connecting post 21 passes through the cover plate body 1 and the upper plastic 6. The rivet block 22 is located on the side of the upper plastic 6 away from the cover plate body 1. The connecting post 21 and the rivet block 22 are riveted together to fix the pole post 2, the upper plastic 6, and the cover plate body 1. The upper plastic 6 is positioned in the positioning groove 1221, which serves to insulate and isolate the rivet block 22 and the cover plate body 1. An insulating sealing ring is provided between the connecting post 21 and the cover plate body 1, which serves to insulate and seal between the connecting post 21 and the cover plate body 1. The connecting piece 5 and the connecting post 21 can be an integral structure or a separate structure.

[0069] Furthermore, the support platform 121 and the mounting platform 122 are connected to form a stepped boss 12. The distance between the positioning groove 1221 and the edge of the mounting platform 122 in the length direction of the substrate 11 is G2, and the distance between the positioning groove 1221 and the edge of the mounting platform 122 in the width direction of the substrate 11 is G3, where 3mm≤G2≤6mm and 3mm≤G3≤7mm.

[0070] When both the mounting platform 122 and the positioning groove 1221 are formed by stamping, if the distance between the positioning groove 1221 and the edge of the mounting platform 122 is too small, it will affect the stamping yield of the mounting platform 122 and the positioning groove 1221. Furthermore, during the assembly of the pole post 2, the support platform 121 may interfere with the assembly operation, which is not conducive to the assembly of the pole post 2. If the distance between the positioning groove 1221 and the edge of the mounting platform 122 is too large, it will reduce the area of ​​the positioning groove 1221, which is also not conducive to the assembly of the pole post 2.

[0071] This implementation improves the stamping yield of the positioning groove 1221 and the mounting platform 122 by setting 3mm≤G2≤6mm and 3mm≤G3≤7mm, ensuring the structural strength of the mounting platform 122, preventing deformation of the positioning groove 1221, and improving the assembly yield of the pole post 2 and the cover plate body 1. Simultaneously, during the assembly process of the pole post 2 and the cover plate body 1, the support platform 121 will not interfere with the operating equipment.

[0072] like Figure 4 As shown, in some embodiments of the present invention, the distance between the support platform 121 and the mounting platform 122 and the edge of the substrate 11 in the width direction is G4, where 3mm≤G4≤7mm.

[0073] The distances between the support platform 121 and the mounting platform 122 and the edge of the substrate 11 can be the same or different. The periphery of the substrate 11 is used for welding to the cell housing. When the support platform 121, mounting platform 122 and substrate 11 are integrally stamped, if the G4 value is too small, it will affect the stamping yield of the support platform 121 and mounting platform 122, and the edge of the substrate 11 will be prone to deformation or cracking; if the G4 value is too large, it will reduce the area of ​​the support platform 121 and mounting platform 122, affect the effect of structural reinforcement, reduce the contact area between the support platform 121 and the housing, and is not conducive to the setting of the pole post 2.

[0074] like Figure 5 As shown, in some embodiments of the present invention, the height of the mounting platform 122 relative to the substrate 11 in the thickness direction is H1, where 1mm ≤ H1 ≤ 2mm. Specifically, when the mounting platform 122 is formed by stamping, if the value of H1 is too low, the reinforcement effect on the pole post structure will be poor; if the value of H1 is too high, the height of the corresponding support platform 121 needs to be higher, which is not conducive to ensuring the stamping yield of the support platform 121.

[0075] In some embodiments of the present invention, the height of the support platform 121 relative to the electrode post 2 in the thickness direction of the substrate 11 is H2, where 1.5mm ≤ H2 ≤ 2.5mm. This height difference allows for the placement of a busbar on the top of the electrode post 2, ensuring that the height of the busbar relative to the substrate 11 is lower than the height of the support platform 121 relative to the substrate 11. If the value of H2 is too small, the space between the electrode post 2 and the housing is insufficient to place the busbar; if the value of H2 is too large, it is difficult to guarantee the stamping yield and will result in wasted space, which is not conducive to improving the utilization rate of the internal space of the battery pack.

[0076] like Figures 6-8 As shown, the battery cell cover provided in this embodiment of the invention further includes a protective component 7. The protective component 7 includes a patch 71 and a plastic part 72. The patch 71 is bonded to the substrate 11 and has a through hole 710 for the stepped boss 12 to pass through. (See also...) Figure 11The plastic part 72 includes a retaining portion 721 and a covering portion 722. The retaining portion 721 is in contact with the side of the patch 71 away from the substrate 11 and surrounds the through hole 710. The covering portion 722 is connected to the end of the retaining portion 721 away from the patch 71 and forms a window. The pole post 2 is opposite to the window, and the covering portion 722 is bonded to the top surface of the support platform 121 and / or the end face of the pole post 2.

[0077] The protective component 7 is disposed on the first side of the cover plate body 1. A patch 71 is attached to the side of the substrate 11 facing the support platform 121, forming an insulating protection for the substrate 11. A plastic part 72 is correspondingly disposed with a stepped boss 12, the stepped boss 12 passing through a through hole 710 on the patch 71, and a retaining portion 721 surrounds the through hole 710, i.e., surrounds the boss. The retaining portion 721 has a certain height relative to the patch 71 in the thickness direction of the substrate. A covering portion 722 is connected to the retaining portion 721 and extends inwards from the retaining portion 721 in a direction parallel to the substrate 11, allowing the covering portion 722 to be bonded to the top surface of the support platform 121 and / or the end face of the pole 2. The opening formed by the covering portion 722 faces the pole 2, facilitating the welding of the pole 2 to the busbar.

[0078] It is understandable that the patch 71 and the plastic part 72 are two independent structural components and can be manufactured separately. During assembly, the patch 71 is first glued and fixed to the substrate 11, and then the plastic part 72 is glued and fixed to the top surface of the support platform 121 and / or the end face of the pole post 2. This helps to improve the bonding yield between the patch 71 and the cover plate body 1. The top surface of the support platform 121 is the side away from the substrate 11, and the end face of the pole post 2 is the side of the end protruding from the boss that is away from the substrate 11. The wall thickness of the plastic part 72 can be set to be thicker, and it has higher rigidity than the patch 71, so as to facilitate assembly with the stepped boss 12.

[0079] The cover plate body 1 is provided with an injection hole 1211 communicating with the receiving cavity. The protective component 7 is disposed on the side of the cover plate body 1 away from the receiving cavity, avoiding the injection hole 1211. After the cell assembly is completed, electrolyte is injected into the cell through the injection hole 1211.

[0080] With the injection hole 1211 located on the substrate 11, the stepped boss 12 prevents electrolyte from flowing into the mating gap between the electrode post 2 and the cover plate body 1, thus preventing sealing failure. The patch 71 also provides protection for the substrate 11, and the enclosure portion 721 of the plastic component 72 prevents electrolyte from entering between the patch 71 and the cover plate body 1 through the through hole 710, thereby avoiding corrosion of the cover plate body 1 by the electrolyte. The stepped boss 12 and the protective assembly 7 provide reliable protection for the substrate 11 and the electrode post 2. Simultaneously, by bonding the covering portion 722 of the plastic component 72 to the top surface of the support platform 121 and / or the end face of the electrode post 2, a separate design for the plastic component 72 and the patch 71 can be achieved, improving the bonding yield of the protective assembly 7 and the cover plate body 1.

[0081] like Figure 7 As shown, patch 71 is bonded and fixed to substrate 11 by adhesive layer. After bonding, the distance between patch 71 and the edge of substrate 11 is 'a', where 0.5mm ≤ a ≤ 1.5mm. If the value of 'a' is too small, patch 71 may easily extend beyond the edge of substrate 11 due to assembly errors in actual production, which is not conducive to the welding of substrate 11 and cell housing. If the value of 'a' is too large, patch 71 will not provide sufficient protection for substrate 11.

[0082] like Figure 9 and Figure 10 As shown, in some embodiments of the present invention, the covering portion 722 is provided with a first notch 7241, through which the busbar connected to the pole post 2 can pass. The enclosure portion 721 is provided with a second notch 7242 corresponding to the position of the first notch 7241, and the first notch 7241 and the second notch 7242 communicate to form an avoidance notch 724.

[0083] The clearance notch 724 can be oriented towards the width direction of the substrate 11, and the first notch 7241 and the second notch 7242 have the same dimensions in the length direction of the substrate 11. Alternatively, the clearance notch 724 can be oriented towards the length direction of the substrate 11, and the first notch 7241 and the second notch 7242 have the same dimensions in the width direction of the substrate 11. When the bus is connected to the terminal post 2, the bus passes through the clearance notch 724, and there is a certain distance between the blocking part 721 and the covering part 722 and the bus. During the welding of the bus and the terminal post 2, the heat of welding can be prevented from causing the plastic part 72 to melt.

[0084] like Figure 7 and Figure 9 As shown, the cover portion 722 includes a first frame portion 7221 and a second frame portion 7222 connected in the length direction of the substrate 11. The first frame portion 7221 surrounds and forms a first opening 7231 and covers the top periphery of the support platform 121, and the second frame portion 7222 surrounds and forms a second opening 7232 and covers the top periphery of the mounting platform 122.

[0085] Among them, the covering portion 722 further includes an inclined portion. The first frame portion 7221 and the second frame portion 7222 are connected by the inclined portion to form a stepped covering portion 722 similar to the shape of the Chinese character "日" (sun). The first notch 7241 is provided in the second frame portion 7222, and the first frame portion 7221 surrounds the top of the support platform 121 in a circle. The covering portion 722 can be bonded to the top surface of the support platform 121 through the first frame portion 7221, and / or bonded to the end surface of the pole column 2 through the second frame portion 7222.

[0086] In this embodiment, by providing the first window 7231, the top surface of the support platform 121 can be bonded to the box body through glue, ensuring the heat conduction efficiency between the support platform 121 and the box body. When bonding the support platform 121 and the box body, the second frame portion 7222 can also play a role in preventing glue overflow, ensuring the thickness of the glue layer, and improving the bonding reliability between the support platform 121 and the box body. The second window 7232 is used for welding the bus bar to the pole column 2.

[0087] As Figure 10 shown, in some embodiments of the present invention, a first glue layer 731 is provided on one side of the first frame portion 7221 facing the through hole 710. The first glue layer 731 is annularly arranged around the first window 7231 and is bonded to the top surface of the support platform 121. In this embodiment, the liquid injection hole 1211 can be provided on the support platform 121. The first glue layer 731 plays an annular sealing role between the first frame portion 7221 and the support platform 121, and can prevent the electrolyte from flowing into the gap between the plastic part 72 and the support platform 121 and between the protection component 7 and the cover body 1. The liquid injection hole 1211 is provided on the support platform 121, which can avoid occupying the space of the substrate 11 by the liquid injection hole 1211.

[0088] In some embodiments of the present invention, a second glue layer 732 is provided on one side of the second frame portion 7222 facing the through hole 710. The second glue layer 732 is arranged along the circumferential direction of the second frame portion 7222 and is bonded to the end surface of the pole column 2. Among them, the second frame portion 7222 is provided with a first notch 7241. Correspondingly, the second glue layer 732 also has a notch at the position corresponding to the first notch 7241. The circumferential length of the second glue layer 732 along the circumferential direction of the second frame portion 7222 can be the same as the circumferential length of the second frame portion 7222 to increase the bonding area between the second frame portion 7222 and the pole column 2.

[0089] Among them, there are certain gaps between the riveting block 22 and the upper plastic 6, and between the upper plastic 6 and the positioning groove 1221. If the electrolyte enters these gaps, it is easy to damage the internal insulating sealing ring, resulting in the sealing failure between the pole column 2 and the cover body 1. See Figure 12In this embodiment, the second frame portion 7222 is bonded to the end face of the pole post 2 through the second adhesive layer 732, so that part of the gap between the rivet block 22 and the upper plastic 6 and part of the gap between the upper plastic 6 and the positioning groove 1221 are covered by the second frame portion 7222, and the second adhesive layer 732 plays the role of blocking the electrolyte, reducing the risk of electrolyte entering these gaps.

[0090] like Figure 10 As shown, the plastic part 72 also includes a partition 74. The partition 74 protrudes from the side of the cover 722 facing the through hole 710, and the partition 74 is located between the pole post 2 and the support platform 121.

[0091] Specifically, the partition 74 is connected to the side of the second frame portion 7222 facing the through hole 710. The partition 74 is located between the top surface of the second frame portion 7222 and the mounting platform 122, and is separated between the pole post 2 protruding from the mounting platform 122 and the support platform 121. The partition 74 extends from one side of the enclosure portion 721 to the opposite side along the width direction of the substrate 11, and the first window 7231 and the second window 7232 are located on both sides of the partition 74, respectively.

[0092] The cover plate body 1 is usually made of metal. The distance between the support platform 121 and the pole post 2 is relatively close, which can easily cause creepage and arcing. In this embodiment, by setting a partition 74 on the plastic part 72 between the pole post 2 and the support platform 121, a good insulation and isolation effect can be achieved between the pole post 2 and the support platform 121, which can reduce the risk of creepage and arcing of the battery cell.

[0093] Furthermore, such as Figure 12 As shown, in the thickness direction of the substrate 11, the distance between the partition 74 and the mounting platform 122 is b, where 0.2mm ≤ b ≤ 0.5mm. If the value of b is too small, in actual production, due to processing and assembly errors, the partition 74 is prone to interference with the mounting platform 122, causing the plastic part 72 to fail to bond with the top surface of the boss and / or the end face of the pole post 2; if the value of b is too large, it will reduce the insulation and isolation effect of the partition 74 on the pole post 2 and the support platform 121.

[0094] In some embodiments of the present invention, the distance between the enclosure portion 721 and the peripheral side surface of the boss in the direction parallel to the substrate 11 is c, where 0.2mm ≤ c ≤ 0.5mm. And / or, in the thickness direction of the substrate 11, the distance between the second frame portion 7222 and the top surface of the support platform 121 is d, where 0.2mm ≤ d ≤ 0.5mm.

[0095] Both the support platform 121 and the mounting platform 122 have a top surface and a side surface connected to the top surface. The side surface of the mounting platform 122 connects to a portion of the side surface of the support platform 121 to form the peripheral side surface of the boss. Another portion of the side surface of the support platform 121 connects to its top surface and the top surface of the mounting platform 122. If the value of c is too small, interference may easily occur between the plastic part 72 and the boss in the horizontal direction; if the value of c is too large, the material of the plastic part 72 will be wasted. If the value of d is too small, it will affect the setting of the first adhesive layer 731; if the value of d is too large, it may cause the first frame portion 7221 to fail to bond with the support platform 121 or the second frame portion 7222 to fail to bond with the pole post 2.

[0096] In some embodiments of the present invention, the thickness of the patch 71 is T1, where 0.2 mm ≤ T1 ≤ 0.3 mm. The wall thickness of the enclosure portion 721 and the covering portion 722 is T2, where 0.9 mm ≤ T2 ≤ 1.2 mm. If the T1 value is too small, the patch 71 is prone to wrinkling, resulting in a low bonding yield; if the T1 value is too large, material is wasted. If the T2 value is too small, the plastic part 72 has insufficient structural strength; if the T2 value is too large, material is wasted.

[0097] like Figure 7 As shown, in some embodiments of the present invention, the patch 71 includes an adhesive portion 711 and a separating portion 712. The separating portion 712 is opposite to the explosion-proof valve 3 in the thickness direction of the substrate 11. A scribe line 713 is provided between the separating portion 712 and the adhesive portion 711. When the explosion-proof valve 3 is opened, the patch 71 can be torn along the scribe line 713 to form an exhaust port.

[0098] Understandably, the scoring line 713 is arranged around the separation part 712 and the explosion-proof valve 3. Before the explosion-proof valve 3 is opened, the scoring line 713 is not broken, and the separation part 712 plays a role in protecting the explosion-proof valve 3, so there is no need to set up a separate explosion-proof valve 3 protection patch 71.

[0099] If the internal pressure of the battery cell exceeds the safety threshold of the explosion-proof valve 3, the explosion-proof valve 3 is opened by the high-pressure gas. Under the gas pressure, the patch 71 is torn at the scribe line 713, causing at least a portion of the separating part 712 to separate from the bonding part 711, forming an exhaust port on the patch 71, from which the gas is discharged to prevent the patch 71 from affecting the exhaust effect.

[0100] The scoring line 713 can wrap around the separating portion 712, allowing the separating portion 712 to completely separate from the fitting portion 711 under air pressure. Alternatively, the scoring line 713 can wrap around a portion of the separating portion 712, allowing the separating portion 712 to partially separate from the fitting portion 711 under air pressure and fold relative to the fitting portion 711. When the scoring line 713 wraps around a portion of the separating portion 712, the scoring line 713 corresponds to the opening side of the explosion-proof valve 3.

[0101] Traditional cell cover plates have a separate patch at the explosion-proof valve. During electrolyte injection, electrolyte can easily flow to the explosion-proof valve, causing the patch to detach and leading to contamination and corrosion of the valve. This embodiment addresses this by providing a separation part 712 on the patch 71. The separation part 712 is connected to the bonding part 711 by a scoring line 713. This not only prevents the patch from detaching to effectively protect the explosion-proof valve but also allows the vent to be opened when the explosion-proof valve 3 is open.

[0102] Furthermore, a pre-drilled hole 714 is defined between the separating part 712 and the bonding part 711. By providing the pre-drilled hole 714, it is convenient to test the airtightness of the explosion-proof valve 3 after the battery cell assembly is completed.

[0103] like Figure 13 As shown, this embodiment of the invention also provides a battery cell, including a battery cell housing 8, an electrode assembly, and a battery cell cover plate as described in any of the above embodiments. The battery cell housing 8 has an opening, and the battery cell cover plate is disposed at the opening and surrounds the battery cell housing 8 to form a receiving cavity. The electrode assembly is disposed within the receiving cavity, and the electrode tabs of the electrode assembly are connected to the electrode posts 2.

[0104] When assembling the battery cell, the pole posts 2 of the electrode assembly and the cell cover plate are welded together first, and the cell cover plate is assembled to one end of the electrode assembly. Then, the electrode assembly is inserted into the cell housing 8 through the opening, and the cover plate body 1 is welded to the cell housing 8. Before being inserted into the housing, the outside of the electrode assembly is usually wrapped with an insulating film to provide insulation between the electrode assembly and the cell housing 8.

[0105] The length dimension of the cover plate body is defined as L, and the width dimension is defined as W. Based on the parameter value ranges defined in this embodiment of the invention, a Design of Experiments (DOE) is conducted using cover plate bodies with dimensions of 150mm≤L≤300mm and 25mm≤W≤75mm as the test subjects. After the cover plate body is stamped, any stamping abnormalities are detected. During the assembly of the battery cell cover, the assembly of the explosion-proof valve and the terminal post with the cover plate body is checked. After the battery cells are assembled, a Z-axis (thickness direction of the substrate) stamping test is performed on the battery pack to detect the surface stress of the cover plate body. The experimental results are shown in Table 1, where H1, H2, G1, G2, G3, and G4 are in mm.

[0106] Table 1: Experimental Data

[0107] 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 a base plate, a support platform and a mounting platform. The support platform and the mounting platform protrude from the same side of the base plate along the thickness direction of the base plate and are arranged along the length direction of the base plate. The cover plate body is provided with a through hole penetrating the mounting platform. The pole post passes through the through hole and protrudes from the mounting platform. In the thickness direction, the height of the support platform relative to the substrate is greater than the height of the end of the pole post protruding from the mounting platform relative to the substrate.

2. The cell cover plate according to claim 1, characterized in that, The support platform and the mounting platform are connected to form a stepped boss.

3. The cell cover plate according to claim 1, characterized in that, Also includes: An explosion-proof valve is disposed on the base plate. There are two support platforms and two mounting platforms. In the length direction, the two support platforms are disposed on both sides of the explosion-proof valve, and the two mounting platforms are disposed on both sides of the explosion-proof valve. The support platform is located between the explosion-proof valve and the mounting platform.

4. The cell cover plate according to claim 1, characterized in that, A first groove is formed on the side of the cover plate body away from the support platform, corresponding to the position of the support platform, and / or a second groove is formed on the side of the cover plate body away from the support platform, corresponding to the position of the mounting platform.

5. The cell cover plate according to claim 4, characterized in that, Also includes: An insulating element is disposed on the side of the substrate away from the support platform. The pole passes through the insulating element. A protrusion is formed on the side of the insulating element near the cover plate body. The first groove and the second groove are connected to form a stepped groove. The protrusion is located in the stepped groove. A stepped groove is formed on the side of the insulating element away from the substrate corresponding to the position of the protrusion.

6. The cell cover plate according to claim 5, characterized in that, Also includes: A connecting piece is located within the stepped groove. A portion of the connecting piece is connected to the pole post, and another portion is opposite to the support platform in the thickness direction and is adapted to connect to the pole lug of the pole assembly.

7. The cell cover plate according to claim 1, characterized in that, The angle between the side wall of the support platform and the substrate is 90°+β, and the angle between the side wall of the mounting platform and the substrate is 90°+γ, where 15°≤β≤25° and 15°≤γ≤25°.

8. The cell cover plate according to claim 1, characterized in that, The substrate is provided with a mounting groove for mounting an explosion-proof valve. In the length direction, the support platform is located between the mounting groove and the mounting platform. The distance between the support platform and the mounting groove is G1, where G1 ≥ 3 mm. And / or, the cell cover plate further includes an upper plastic, the top of the mounting platform is provided with a positioning groove, the upper plastic is disposed in the positioning groove, the electrode post passes through the upper plastic, the support platform and the mounting platform are connected to form a stepped boss, the distance between the positioning groove and the edge of the mounting platform in the length direction is G2, the distance between the positioning groove and the edge of the mounting platform in the width direction of the substrate is G3, 3mm≤G2≤6mm, 3mm≤G3≤7mm; And / or, in the width direction of the substrate, the distance between the support platform and the mounting platform and the edge of the substrate is G4, where 3mm≤G4≤7mm.

9. The cell cover plate according to claim 1, characterized in that, The height of the mounting platform relative to the substrate in the thickness direction is H1, where 1.0mm≤H1≤2mm; And / or, the height of the support platform relative to the pole in the thickness direction is H2, 1.5mm≤H2≤2.5mm.

10. A battery cell, characterized in that, include: The battery cell casing has an opening; The cell cover plate as described in any one of claims 1 to 9, wherein the cell cover plate is disposed at the opening and surrounds the cell housing to form a receiving cavity; An electrode assembly is disposed within the receiving cavity, and the electrode tabs of the electrode assembly are connected to the electrode post.

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