Battery cell cover plate and battery cell

Abstract

The invention relates to the technical field of batteries, and provides a battery cell cover plate and a battery cell. The battery cell cover plate comprises a cover plate body, one side of the cover plate body is provided with a reference surface, a supporting boss is formed on the reference surface, and the supporting boss is arranged on the reference surface in a protruding mode; the protection part is arranged on the outer side of the cover plate body, the outer side of the cover plate body is the side provided with the supporting boss, the shape of the protection part is matched with that of the supporting boss, and the protection part covers the supporting boss; and the height of the support boss relative to the reference surface is greater than the height of the pole protruding out of the reference surface. According to the battery cell cover plate provided by the embodiment of the invention, a reliable physical insulation barrier is constructed between the high-voltage pole and the cover plate body made of the metal material by arranging the protective piece which is matched with the supporting boss in shape and covers the supporting boss. Therefore, the high risk that high-voltage creepage or arc pulling is possibly generated in the air gap between the pole and the boss due to the fact that the conductive boss is additionally arranged is fundamentally solved, and the electrical safety under the complex working condition is ensured.

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] Lithium-ion batteries have become important components in power batteries, energy storage devices, and other fields due to their high energy density and long cycle life. As the smallest unit of the battery pack, the cell's cover is not only a key component for sealing the casing and fixing the terminals, but it also usually integrates functional elements such as explosion-proof valves and electrolyte injection holes. Its structural design directly affects the overall performance of the cell and the battery pack.

[0003] To optimize space and heat dissipation, existing cell covers feature raised structures on their surfaces to fill the gap with the upper casing, increasing contact and heat dissipation area. However, the introduction of such raised structures brings new safety risks: the high-voltage terminals on the cell cover are very close to the raised structures. Under complex operating conditions such as high voltage, dust, and humidity, electrical creep and even arcing can easily occur between the raised structures and terminals, leading to cell short circuits and seriously threatening battery safety. Summary of the Invention

[0004] This invention provides a cell cover plate and a cell to solve the problem that the current cell cover plate terminals are prone to creepage and even arcing with the bosses, which leads to short circuits in the cell.

[0005] This invention provides a battery cell cover plate, comprising: The cover plate body has a reference surface on one side, and a support boss is formed on the reference surface, the support boss protruding from the reference surface; A protective component is disposed on the outside of the cover plate body, the outside of the cover plate body being the side with the supporting boss, the shape of the protective component being adapted to the supporting boss and covering the supporting boss; The pole has one end passing through the reference surface, and the height of the support boss relative to the reference surface is greater than the height of the pole protruding from the reference surface.

[0006] According to the present invention, a battery cell cover plate is provided, wherein the supporting boss includes: a first boss and a second boss; both the first boss and the second boss protrude from the reference surface, and the height of the first boss relative to the reference surface is greater than the height of the second boss relative to the reference surface; An explosion-proof valve is provided on the first protrusion. The protective component covers the first protrusion and the second protrusion. The protective component shields the explosion-proof valve on the outside away from the battery cell housing. The protective component has a notch corresponding to the position of the explosion-proof valve.

[0007] According to a battery cell cover provided by the present invention, the edges of the first boss and / or the second boss are formed with reinforcing ribs, and the protective member is formed with a slot corresponding to the position of the reinforcing rib, the slot being adapted to the reinforcing rib to limit the position of the protective member.

[0008] According to a battery cell cover provided by the present invention, the first boss and / or the second boss are provided with an adhesive application area for providing an adhesive layer, and the protective member is fixed to the first boss and / or the second boss by the adhesive layer.

[0009] According to the present invention, the first boss and the second boss are both conical bosses. The angle between the sidewall of the first boss and the direction perpendicular to the reference plane is γ, and the angle between the sidewall of the second boss and the direction perpendicular to the reference plane is β, satisfying 20 degrees ≤ β = γ ≤ 25 degrees.

[0010] According to the present invention, the protective member has a wall thickness of c; the gap between the protective member and the second boss is d along the height direction of the cover body, and the gap between the protective member and the surface of the first boss is e, satisfying 0.9mm≤c≤1.3mm, 0.2mm≤d≤0.5mm, and 0.5mm≤e≤1mm.

[0011] According to a battery cell cover provided by the present invention, an upper plastic is provided on the reference surface, and one end of the electrode post passes through the reference surface and is disposed in the upper plastic; Along the length or width of the cover plate body, the distance between the upper plastic and the edge of the reference surface is a; along the length of the cover plate body, the distance between the upper plastic and the support boss is b, where 2mm≤a≤5mm, 3mm≤b≤5mm.

[0012] According to the present invention, in a battery cell cover, the distance between the upper plastic and the protective member along the length or width direction of the cover body is f, which satisfies 1mm≤f≤2mm.

[0013] According to the present invention, a battery cell cover is provided, wherein the protective component is made of polypropylene material, wherein the polypropylene material has a tensile strength ≥125MPa, a flexural strength ≥175MPa, a flexural modulus ≥10000MPa, and a heat distortion temperature ≥230℃.

[0014] The present invention also provides a battery cell, comprising: The battery cell casing has an opening; The aforementioned 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.

[0015] The battery cell cover provided in this embodiment constructs a reliable physical insulation barrier between the high-voltage terminal and the metal cover body by setting a protective component that adapts to the shape of the supporting boss and covers it. This fundamentally solves the high risk of high-voltage creepage or arcing that may be caused by adding conductive bosses in the air gap between the terminal and the boss, ensuring electrical safety under complex working conditions.

[0016] Furthermore, the height of the support boss relative to the reference plane is greater than the height of the terminal post protruding from the reference plane. During battery assembly, the support boss can contact the upper casing or adjacent components before the terminal post, thereby directly distributing external loads to the cover plate body and the entire cell casing through the support boss. This effectively avoids the problem of excessive stress concentration on the terminal post in traditional structures, significantly improving the mechanical structural strength and impact and compression resistance of individual cells and the entire battery pack. Moreover, the cooperation between the support boss structure itself and the protective components greatly increases the effective contact area between the cover plate surface and the external upper casing or heat dissipation structure. Heat can be conducted away more efficiently from the cover plate body, the support boss, and through the protective components, effectively reducing the cell operating temperature. 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 a three-dimensional structural diagram of the battery cell cover plate provided by the present invention.

[0019] Figure 2 This is a disassembly diagram of the battery cell cover plate provided by the present invention.

[0020] Figure 3 This is a three-dimensional structural diagram of the protective component provided by the present invention.

[0021] Figure 4 This is one of the cross-sectional schematic diagrams of the battery cell cover plate provided by the present invention.

[0022] Figure 5 This is a schematic diagram of the side of the protective component provided by the present invention.

[0023] Figure 6 This is the second cross-sectional schematic diagram of the battery cell cover plate provided by the present invention.

[0024] Figure 7This is one of the top views of the battery cell cover plate provided by the present invention.

[0025] Figure 8 This is a second top view of the battery cell cover plate provided by the present invention.

[0026] Figure 9 This is a schematic diagram of the battery cell provided by the present invention.

[0027] Figure label: 1. Cell cover plate; 11. Cover plate body; 111. Reference surface; 112. Support boss; 1121. First boss; 1122. Second boss; 1123. Reinforcing rib; 1124. Glue application area; 12. Protective component; 13. Explosion-proof valve; 14. Explosion-proof valve patch; 15. Terminal post; 16. Upper plastic; 17. Riveting block; 18. Lower plastic; 2. Cell housing. Detailed Implementation

[0028] 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.

[0029] 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.

[0030] In some embodiments, such as Figures 1 to 3 As shown, the cell cover 1 includes: a cover body 11, a terminal post 15, and a protective member 12. One side of the cover body 11 has a reference surface 111, on which a supporting boss 112 is formed, protruding from the reference surface 111. The protective member 12 is disposed on the outer side of the cover body 11, the outer side of which is the side with the supporting boss 112. The shape of the protective member 12 is adapted to the supporting boss 112, covering it.

[0031] In this embodiment, see Figure 1 The cover plate body 11 has a plate-like structure and is typically made of a metallic material (such as aluminum or aluminum alloy). The cover plate body 11 has opposing inner sides (facing the inside of the battery cell) and outer sides. A reference plane 111 is defined on its outer side. The length direction of the cover plate body 11 is... Figure 1 The x-axis is the width direction of the cover plate body 11. Figure 1 The y-axis in the figure represents the thickness direction of the cover plate. Figure 1 The z-axis of the cover plate is perpendicular to its length and width directions and to the reference plane 111.

[0032] At least one support boss 112 is formed on the reference surface 111 by, for example, a stamping process. The support boss 112 protrudes outward from the reference surface 111 (i.e., away from the inside of the cell), and its cross-sectional shape can be circular, elliptical, rectangular or other shapes that meet the requirements. Its sidewalls can be vertical, inclined or tapered.

[0033] The terminals 15 are used for the positive and negative leads of the battery cell, and there are usually two of them, serving as the positive terminal and the negative terminal respectively. One end (inner end) of each terminal 15 is used to connect to the internal tab of the battery cell (not shown in the figure), and the other end (outer end) passes through the reference surface 111 of the cover plate body 11 and extends outward for external electrical connection. The protective member 12 is a separate component, preferably made of high-strength insulating engineering plastic. It is disposed on the outside of the cover plate body 11, specifically covering the support boss 112. The protective member 12 has an inner cavity or inner surface that conforms to the outer contour of the support boss 112, so that it can be fitted or installed on the outside of the support boss 112.

[0034] The protrusion height H1 of the support boss 112 relative to the reference surface 111 is greater than the protrusion height H2 of the terminal post 15 from the reference surface 111. In other words, the highest point of the support boss 112 extends beyond the highest point of the outer end of the terminal post 15 in the direction perpendicular to the reference surface 111. When assembled, the upper casing or intermediate structure of the battery pack will preferentially contact the higher-positioned protective component 12 (cover boss), making the support boss 112 the main load-bearing and force transmission path, thereby protecting the terminal post 15 from direct mechanical impact or compression and improving reliability. Secondly, the combination of the support boss 112 and the protective component 12 significantly increases the effective contact area between the outer side of the cover and the outside, which not only improves the stability of the mechanical support but also provides a larger and more direct channel for heat to transfer from the cover body 11 to the outside, improving heat dissipation.

[0035] The battery cell cover 1 provided in this embodiment constructs a reliable physical insulation barrier between the high-voltage terminal 15 and the metal cover body 11 by setting a protective component 12 that is adapted to the shape of the supporting boss 112 and covers it. This fundamentally solves the high risk of high-voltage creepage or arcing that may be caused by adding conductive bosses in the air gap between the terminal 15 and the boss, ensuring electrical safety under complex working conditions.

[0036] In some embodiments, such as Figures 1 to 3 As shown, the support boss 112 includes a first boss 1121 and a second boss 1122. There are two second bosses 1122. The first boss 1121 is located in the middle, and the two second bosses 1122 are respectively located on both sides of the first boss 1121. All three are integrally formed protruding from the reference surface 111. The protrusion height of the first boss 1121 is significantly greater than that of the two second bosses 1122 on both sides, thus forming a stepped support structure on the cover plate surface that is higher in the middle and lower on both sides.

[0037] Based on this structure, an explosion-proof valve 13 is provided on the top or side wall area of ​​the higher first boss 1121. The inner cavity shape of the protective member 12 is designed to match this group of bosses with height differences, thus completely covering the first boss 1121 and the two second bosses 1122. In particular, the protective member 12 extends and shields the explosion-proof valve 13 on the outside away from the cell housing 2, providing it with primary protection against dust and impact, and can prevent external foreign objects from directly impacting or blocking the pressure relief channel of the explosion-proof valve 13 to a certain extent. To ensure the emergency pressure relief function of the explosion-proof valve 13, the protective member 12 has a through-hole precisely opened at the center position corresponding to the explosion-proof valve 13. When the explosion-proof valve 13 is depressurized, gas and substances can be discharged outwards without obstruction through this hole.

[0038] In some embodiments, such as Figures 1 to 3As shown, an explosion-proof valve 13 is provided on the top of the first boss 1121. To enhance the mechanical protection and insulation seal of this vulnerable area while ensuring pressure relief, an explosion-proof valve patch 14 is also fixedly attached to the side of the explosion-proof valve 13 facing away from the battery cell housing 2 (i.e., towards the outside of the battery cell). This explosion-proof valve patch 14 is typically made of a corrosion-resistant, laser-weldable metal sheet. Its edges are sealed to the top surface of the first boss 1121 by laser welding or other methods, while the central area is marked with a predetermined rupture line. The main functions of the explosion-proof valve patch 14 are: first, to act as the pressure-bearing and pressure-relief structure of the explosion-proof valve 13, rupturing at its weak point when the internal pressure exceeds the limit; second, to provide an additional layer of physical protection for the diaphragm of the explosion-proof valve 13 below, preventing accidental puncture during assembly or transportation; and third, to cooperate with the notch on the protective component 12, allowing the patch to be exposed after the protective component 12 is installed, ensuring unobstructed pressure relief. The explosion-proof valve 13 mainly includes an explosion-proof plate. The explosion-proof plate is usually a thin metal film with predetermined cracking marks, which is covered on the pressure relief port of the boss by sealing welding. Its function is to rupture and relieve pressure when the internal pressure of the battery cell reaches a safe threshold.

[0039] In addition, a riveting block 17 may be provided at the end of the terminal post 15 that extends beyond the outer side of the cover plate body 11. This riveting block 17 can be integrally formed with the terminal post 15, or it can be manufactured separately and fixed to the end of the terminal post 15 by welding, pressing, or other methods. The main purpose of providing the riveting block 17 is to provide a welding surface for the subsequent welding of the connecting pads in the battery module, greatly facilitating the welding operation and improving the mechanical strength and electrical reliability of the weld joint; moreover, it increases the contact area between the end of the terminal post 15 and the connecting pads, reducing contact resistance and helping to reduce heat generation and energy loss.

[0040] In some embodiments, such as Figures 1 to 3 As shown, reinforcing ribs 1123 are formed along the edges of the first boss 1121 and / or the second boss 1122. A groove is formed on the protective member 12 corresponding to the position of the reinforcing rib 1123. The groove is adapted to the reinforcing rib 1123 to limit the movement of the protective member 12. When the protective member 12 is installed, the reinforcing rib 1123 on the boss can be embedded into the groove of the protective member 12 along the installation direction. Through the mutual cooperation of the reinforcing rib 1123 and the groove, an effective mechanical limiting and guiding structure is formed. This structure not only guides the protective member 12 to be positioned quickly and accurately during installation, preventing misalignment or tilting, but also, after installation, uses the sides of the rib and the groove to abut against each other, restricting the movement of the protective member 12 in the direction parallel to the reference plane 111, thereby achieving the limiting of the protective member 12 on the supporting boss 112 without the need for additional fasteners.

[0041] In some embodiments, such as Figures 1 to 3As shown, the first boss 1121 and / or the second boss 1122 are provided with an adhesive application area 1124 for applying an adhesive layer, and the protective member 12 is fixed to the first boss 1121 and / or the second boss 1122 by the adhesive layer.

[0042] Specifically, the adhesive application area 1124 is typically positioned on a relatively flat surface of the boss, facilitating adhesive spread and retention. For example, such an adhesive application area 1124 can be provided on the second boss 1122, in the recess or flat portion formed between its two reinforcing ribs 1123. During installation, an adhesive (such as epoxy structural adhesive, thermally conductive adhesive, or other specialized adhesive) is applied to this adhesive application area 1124 in a specific shape and dosage to form an adhesive layer. Subsequently, the protective member 12 (which has a groove on its inner side that mates with the reinforcing rib 1123) is fitted onto the supporting boss 112 in a predetermined direction, allowing the reinforcing rib 1123 to slide into the corresponding groove for positioning. During this process, the inner wall of the protective member 12 comes into contact with and presses against the adhesive layer of the adhesive application area 1124. After the adhesive layer cures, a chemical bond is formed between the protective member 12 and the second boss 1122. This composite fixing method not only effectively prevents the protective component 12 from loosening from the boss under vibration, impact or thermal cycling, but also fills the micro gaps to a certain extent, improving the tightness of the connection and the overall structural rigidity.

[0043] In some embodiments, such as Figure 4 As shown, both the first boss 1121 and the second boss 1122 are tapered bosses. The angle between the sidewall of the first boss 1121 and the direction perpendicular to the reference plane 111 is γ, and the angle between the sidewall of the second boss 1122 and the direction perpendicular to the reference plane 111 is β.

[0044] Specifically, the sidewall of each boss is not perpendicular to the reference plane 111, but rather at a specific angle to the perpendicular direction of the reference plane 111. This tapered design not only facilitates the stamping and forming of sheet metal and improves production yield, but also provides more optimized space for internal tab bending or other components.

[0045] The acute angle formed between the sidewall of the first boss 1121 and the direction perpendicular to the reference plane 111 (i.e., the normal direction) is defined as γ; correspondingly, the acute angle formed between the sidewall of the second boss 1122 and the same normal direction is defined as β. In this scheme, these two angles are set to be equal, i.e., β = γ, and their values ​​are jointly restricted to a closed interval of 20 degrees to 25 degrees.

[0046] Within this angle range, the boss has sufficient structural rigidity to withstand external pressure; given the limited planar space of the cover plate, it can maximize the usable longitudinal depth inside the cell (especially the tab area); at the same time, this angle range is also within the window of stable stamping process and good material flow, avoiding defects such as tensile cracking caused by too small an angle or wrinkling caused by too large an angle, thereby ensuring the quality and efficiency of production.

[0047] like Figure 5 As shown, to ensure that the protective component 12 can cover the first boss 1121 and the second boss 1122, the protective component 12 has an internal cavity structure that matches the bosses. Specifically, the taper of the inner wall region of the protective component 12 corresponding to the first boss 1121 and the second boss 1122 is consistent with the taper of the side walls of the first boss 1121 and the second boss 1122. That is, the inclination angle of the inner wall of the protective component 12 corresponding to the first boss 1121 is also γ, and the inclination angle corresponding to the second boss 1122 is also β, and γ=β, with the values ​​ranging from 20 degrees to 25 degrees. This taper ensures that the inner surface of the protective component 12 and the outer surface of the boss can achieve a large-area uniform fit. It optimizes the contact between the two, reduces air gaps, and thus improves the heat conduction efficiency from the cover plate body 11 through the bosses to the protective component 12; moreover, during assembly, the same taper plays a natural guiding and centering role, allowing the protective component 12 to be installed more smoothly and reducing the assembly difficulty.

[0048] In some embodiments, such as Figures 1 to 3 as well as Figure 6 As shown, the wall thickness of the protective member 12 is c, the gap between the protective member 12 and the second boss 1122 is d, and the gap between the protective member 12 and the surface of the first boss 1121 is e, satisfying 0.9mm≤c≤1.3mm, 0.2mm≤d≤0.5mm, and 0.5mm≤e≤1mm.

[0049] Specifically, the wall thickness of the protective component 12 is defined as dimension c. This wall thickness c is controlled within the range of 0.9 mm to 1.3 mm. A wall thickness greater than or equal to 0.9 mm provides the necessary structural strength for the protective component 12, ensuring that it does not break or permanently deform under battery pack assembly, use, and possible minor mechanical impacts, thus maintaining the integrity of its insulation barrier. A wall thickness less than or equal to 1.3 mm effectively controls its material cost and overall weight, avoiding process problems such as injection molding difficulties and uneven cooling caused by excessive wall thickness, while also facilitating layout within a limited space.

[0050] Along the height of the cover plate body 11, the distance between the inner surface of the protective member 12 and the outer surface of the second boss 1122 is d. This gap d is between 0.2 mm and 0.5 mm. This gap provides the necessary tolerance space for the assembly of the protective member 12 on the second boss 1122, preventing assembly interference or stress concentration caused by manufacturing tolerances or thermal expansion and contraction; on the other hand, a sufficiently small gap can minimize the air layer, optimize the heat conduction path from the second boss 1122 through the protective member 12 to the outside, improve heat dissipation efficiency, and help maintain a uniform electric field distribution between the two, enhancing insulation performance.

[0051] In the area of ​​the first boss 1121, particularly where the explosion-proof valve 13 may be located on its top or side wall, the distance between the inner surface of the protective member 12 and the surface of the first boss 1121 is e along the height direction of the cover body 11. This gap is between 0.5 mm and 1 mm. On the one hand, this gap provides the necessary discharge space for the pressure relief action of the explosion-proof valve 13, ensuring reliable pressure release in emergency situations; on the other hand, it also provides sufficient structural space for the protective member 12 to effectively cover the explosion-proof valve 13 without contact, achieving both physical protection and avoiding potential obstruction of the normal opening of the explosion-proof valve 13 due to contact.

[0052] In some embodiments, such as Figures 1 to 3 as well as Figure 7 As shown, an upper plastic 16 is provided on the reference surface 111, and one end of the pole post 15 passes through the reference surface 111 and is set in the upper plastic 16; the distance between the upper plastic 16 and the edge of the reference surface 111 is a, and the distance between the upper plastic 16 and the support boss 112 is b, 2mm≤a≤5mm, 3mm≤b≤5mm.

[0053] In this embodiment, the minimum distance 'a' between the boundary of the upper plastic 16 and the outer edge of the reference surface 111 of the cover plate body 11 (i.e., the edge typically welded to the cell housing 2) along the length or width direction of the cover plate body 11 is defined as 'a'. This distance 'a' is limited to a range of 2 mm to 5 mm. This range provides a sufficiently clean welding area for laser welding or other welding processes between the cover plate body 11 and the cell housing 2, preventing damage to the upper plastic 16 from welding heat or spatter, ensuring weld airtightness and yield; and ensuring sufficient insulation distance between the edge of the upper plastic 16 and the high-voltage terminal 15, as well as the cover plate edge that may be at the same potential as the housing, preventing surface discharge in high humidity or polluted environments.

[0054] Meanwhile, along the length of the cover plate body 11, the minimum distance b between the boundary of the upper plastic 16 near the support boss 112 and the nearest edge of the support boss 112 (or its protective element 12) is between 3 mm and 5 mm. This range defines the spatial distance between the upper plastic 16 and the metal boss. Furthermore, it provides assembly and movement space for the installation of the protective element 12 on the support boss 112 and for possible minor deformations, preventing interference between the upper plastic 16 and the protective element 12 during assembly or temperature changes.

[0055] Furthermore, the cover plate body 11 has a lower plastic 18 on its inner side or bottom, opposite to the outer side where the support boss 112 and the protective member 12 are provided. The lower plastic 18 covers the inner end region of the electrode post 15 that passes through the cover plate body 11, as well as around other openings on the inner side of the cover plate body 11, to achieve reliable insulation between the electrode post 15 and the cover plate body 11 on the inner side, and to assist in forming a sealing barrier.

[0056] In some embodiments, such as Figure 8 As shown, the distance f between the upper plastic 16 and the protective component 12 along the length or width direction of the cover plate body 11 satisfies 1mm ≤ f ≤ 2mm. Both the upper plastic 16 (formed by injection molding) and the protective component 12 have inherent manufacturing tolerances. The gap f is set to be not less than 1 mm, providing the necessary tolerance space for the two during assembly, effectively avoiding direct contact and interference caused by part tolerances, positioning deviations, or assembly stress, and ensuring smooth assembly and high yield.

[0057] Furthermore, the upper plastic 16 encapsulates and insulates the high-voltage terminal 15, while the protective component 12 is tightly fitted onto the metal support boss 112, which is at the same potential as the cover plate body 11. Both are insulators but at different potentials. Maintaining a constant gap f of not less than 1 mm creates a reliable physical isolation air gap between them. This provides a controllable electrical creepage distance and air gap distance between the surface of the upper plastic 16 and the surface of the protective component 12, effectively suppressing the risk of surface discharge or air breakdown even in harsh environments such as humidity, condensation, or pollution.

[0058] It should be noted that the protective component 12 selected in this embodiment is made of polypropylene. Its specific performance parameters are: tensile strength ≥ 125 MPa, flexural strength ≥ 175 MPa, flexural modulus ≥ 10000 MPa, and heat distortion temperature ≥ 230℃. The tensile strength ≥ 125 MPa and flexural strength ≥ 175 MPa ensure that the protective component 12 has extremely high tensile and bending resistance. When the battery module is subjected to external pressure, vibration, or impact, the protective component 12 can effectively resist deformation and breakage, protecting its lower boss structure, explosion-proof valve 13, and maintaining a precise assembly relationship with the boss and cover plate, avoiding insulation failure or mechanical interference due to its own damage. The flexural modulus ≥ 10000 MPa gives the material extremely high rigidity, ensuring excellent dimensional stability of the protective component 12 under long-term support or stress, maintaining a tight fit with the boss and a preset gap, thereby ensuring a stable heat conduction path and electrical clearance. Under extreme operating conditions, the local temperature of lithium-ion batteries may rise significantly. The material of the protective component 12 can maintain sufficient shape stability and mechanical strength at ambient temperatures up to 230°C, without softening, collapsing or significantly deforming.

[0059] like Figure 9 As shown, this embodiment of the invention also provides a battery cell, including: a battery cell housing 2 and the aforementioned battery cell cover plate 1. The battery cell housing 2 has an opening; the battery cell cover plate 1 is disposed at the opening and surrounds the battery cell housing 2 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 posts 15.

[0060] In this embodiment, the cell housing 2 is typically a cylindrical structure with an opening at one end. Its cross-section can be square, circular, or other shapes, and it is made of metallic material to provide mechanical strength, a sealing barrier, and the necessary conductive path. The opening is used to accommodate the electrode assembly and electrolyte.

[0061] The cell cover 1 is sealed to the edge of the opening of the cell housing 2 via a process such as laser welding, through the periphery of the cover body 11 (such as the area of ​​the aluminum sheet), thereby forming a sealed cavity. This cavity is used to encapsulate all the active components of the cell and is filled with electrolyte.

[0062] The electrode assembly, located within the housing cavity, is the site where the electrochemical reaction of the battery cell takes place. It is typically manufactured using a winding or stacking process, consisting of a positive electrode, a negative electrode, and a separator spaced between them. The tabs extending from the electrode assembly extend into the inner side of the battery cell cover plate 1 and are electrically connected and mechanically fixed to the inner end of the electrode post 15 passing through the cover plate body 11 via welding or other methods. The bending and connection space of the tabs is guided, limited, and insulated by the lower plastic structure 18 on the inner side of the cover plate.

[0063] The battery cell provided in this embodiment, due to the aforementioned battery cell cover plate 1, and by setting a protective member 12 that is adapted to the shape of the supporting boss 112 and covers it, a reliable physical insulation barrier is constructed between the high-voltage terminal 15 and the metal cover plate body 11. This fundamentally solves the high risk of high-voltage creepage or arcing that may be caused by the addition of conductive bosses in the air gap between the terminal 15 and the boss, ensuring electrical safety under complex working conditions.

[0064] Furthermore, the height of the support boss 112 relative to the reference surface 111 is greater than the height of the electrode post 15 protruding from the reference surface 111. During battery assembly, the support boss 112 can contact the upper casing or adjacent components before the electrode post 15, thereby directly distributing external loads to the cover plate body 11 and the entire cell casing 2 through the support boss 112. This effectively avoids the problem of excessive stress concentration on the electrode post 15 in traditional structures, significantly improving the mechanical structural strength and impact and compression resistance of individual cells and the entire battery pack. Moreover, the cooperation between the support boss 112 structure and the protective component 12 greatly increases the effective contact area between the cover plate surface and the external upper casing or heat dissipation structure. Heat can be conducted away more efficiently from the cover plate body 11 and the support boss 112 through the protective component 12, effectively reducing the cell operating temperature.

[0065] In one specific embodiment, as shown in Table 1 below, the angle between the sidewall of the first boss 1121 and the direction perpendicular to the reference plane 111 is γ, and the angle between the sidewall of the second boss 1122 and the direction perpendicular to the reference plane 111 is β. Along the length or width direction of the cover plate body 11, the distance between the upper plastic 16 and the edge of the reference plane 111 is a; along the length of the cover plate body 11, the distance between the upper plastic 16 and the supporting boss 112 is b. The wall thickness of the protective member 12 is c. Along the height direction of the cover plate body 11, the gap between the protective member 12 and the second boss 1122 is d, and the gap between the protective member 12 and the surface of the first boss 1121 is e. Along the length or width direction of the cover plate body 11, the distance between the upper plastic 16 and the protective member 12 is f.

[0066] Table 1 β (degree) γ (degrees) A (mm) b (mm) c (mm) d (mm) e (mm) f (mm) Example 1 20.0 20.0 2 3 0.9 0.2 0.5 1 Example 2 21.5 21.5 2.2 3.5 0.95 0.25 0.55 1.1 Example 3 22.0 22.0 2.5 4 1 0.3 0.6 1.2 Example 4 22.5 22.5 2.8 4.5 1.1 0.35 0.65 1.5 Example 5 22.3 22.3 3 5 1.05 0.4 0.7 1.8 Example 6 23.8 23.8 3.5 4.2 1.2 0.45 0.75 1.7 Example 7 22.5 22.5 4 3.8 1.3 0.5 0.8 1.9 Example 8 25.0 25.0 5 3.5 1.25 0.38 0.9 2 Comparative Example 1 20.0 20.0 2 3 0.85 0.2 0.5 1 Comparative Example 2 20.0 20.0 1.7 3 0.9 0.2 0.5 1 Comparative Example 3 22.5 22.5 2.8 4.5 1.1 0.35 0.65 0.8 All parameter combinations in Examples 1 to 8 fall within the optimization range claimed by this invention (20°≤β=γ≤25°, 2mm≤a≤5mm, 3mm≤b≤5mm, 0.9mm≤c≤1.3mm, 0.2mm≤d≤0.5mm, 0.5mm≤e≤1mm, 1mm≤f≤2mm). Test results show that the cover assembly manufactured under these parameters fully meets the structural strength requirements for its protective components. There are no interference issues with the upper plastic, bosses, or other components during assembly, and the finished battery cell passed rigorous insulation performance tests without any insulation defects. This fully demonstrates the feasibility, reliability, and safety of the technical solution of this invention.

[0067] Comparative Example 1: The wall thickness c of the protective component was reduced to 0.85 mm (below the lower limit of 0.9 mm), while other parameters remained the same as in Example 1. The result showed that the protective component itself lacked structural strength, making it prone to deformation during production and assembly. This compromised its shape stability and reliable coverage of the boss, verifying the necessity of minimum wall thickness requirements for maintaining component rigidity.

[0068] Comparative Example 2: The distance 'a' between the upper plastic and the edge of the cover plate was reduced to 1.7 mm (below the lower limit of 2 mm). During laser sealing welding of the cover plate and the housing, the excessively close distance caused the heat-affected zone to extend to the edge of the upper plastic, resulting in localized burns, discoloration, and even deformation of the upper plastic, producing appearance defects and severely affecting the production yield of the battery cell. This indicates that distance 'a' is a critical isolation distance to ensure the safety of the welding process window and the upper plastic.

[0069] Comparative Example 3: The gap f between the upper plastic and the protective component was reduced to 0.8 mm (below the lower limit of 1 mm). Due to the accumulation of manufacturing and assembly tolerances, the upper plastic and the protective component came into contact and interfered during actual assembly, resulting in the protective component failing to be installed properly or generating assembly stress. This proves that the gap f is a necessary assembly tolerance space, and its lower limit must ensure that physical interference is avoided even under the worst tolerance conditions.

[0070] A comparison of the embodiments and comparative examples clearly demonstrates that the range of key parameters defined in this invention is not arbitrarily chosen, but rather derived through thorough optimization and verification under multiple constraints, including structural strength, high-voltage insulation, welding process, assembly feasibility, and thermal management. The successful implementation of the embodiments proves the superiority of the solution within this window, while the comparative examples clearly reveal, from the opposite perspective, the specific technical problems that inevitably arise from deviating from this optimization range.

[0071] 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 has a reference surface on one side, and a support boss is formed on the reference surface, the support boss protruding from the reference surface; A protective component is disposed on the outside of the cover plate body, the outside of the cover plate body being the side with the supporting boss, the shape of the protective component being adapted to the supporting boss and covering the supporting boss; The pole has one end passing through the reference surface, and the height of the support boss relative to the reference surface is greater than the height of the pole protruding from the reference surface.

2. The cell cover plate according to claim 1, characterized in that, The support boss includes: a first boss and a second boss; both the first boss and the second boss protrude from the reference surface, and the height of the first boss relative to the reference surface is greater than the height of the second boss relative to the reference surface; An explosion-proof valve is provided on the first protrusion. The protective component covers the first protrusion and the second protrusion. The protective component shields the explosion-proof valve on the outside away from the battery cell housing. The protective component has a notch corresponding to the position of the explosion-proof valve.

3. The cell cover plate according to claim 2, characterized in that, The first boss and / or the second boss have reinforcing ribs formed along their edges. The protective member has a slot formed at the position of the reinforcing rib. The slot is adapted to the reinforcing rib to limit the position of the protective member.

4. The cell cover plate according to claim 3, characterized in that, The first boss and / or the second boss are provided with an adhesive application area for setting an adhesive layer, and the protective component is fixed to the first boss and / or the second boss by the adhesive layer.

5. The cell cover plate according to claim 2, characterized in that, Both the first boss and the second boss are conical bosses. The angle between the sidewall of the first boss and the direction perpendicular to the reference plane is γ, and the angle between the sidewall of the second boss and the direction perpendicular to the reference plane is β, satisfying 20 degrees ≤ β = γ ≤ 25 degrees.

6. The cell cover plate according to claim 2, characterized in that, The wall thickness of the protective component is c; along the height direction of the cover plate body, the gap between the protective component and the second boss is d, and the gap between the protective component and the surface of the first boss is e, satisfying 0.9mm≤c≤1.3mm, 0.2mm≤d≤0.5mm, and 0.5mm≤e≤1mm.

7. The cell cover plate according to claim 1, characterized in that, The reference surface is provided with an upper plastic layer, and one end of the pole post passes through the reference surface and is disposed in the upper plastic layer; Along the length or width of the cover plate body, the distance between the upper plastic and the edge of the reference surface is a; along the length of the cover plate body, the distance between the upper plastic and the support boss is b, where 2mm≤a≤5mm, 3mm≤b≤5mm.

8. The cell cover plate according to claim 7, characterized in that, Along the length or width of the cover plate body, the distance between the upper plastic and the protective component is f, which satisfies 1mm≤f≤2mm.

9. The cell cover plate according to any one of claims 1-8, characterized in that, The protective component is made of polypropylene material, which has a tensile strength ≥125MPa, a flexural strength ≥175MPa, a flexural modulus ≥10000MPa, and a heat distortion temperature ≥230℃.

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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