Battery cell and battery pack

Abstract

The application relates to the technical field of batteries, and discloses a battery cell and a battery pack. The battery cell comprises a shell, an upper end surface of the shell is provided with a mounting hole in the Z direction, a pole is arranged in the mounting hole and partially extends out of the upper end surface of the shell, a support cover is connected with the upper end surface of the shell and is arranged in a spaced mode with the pole in the Z direction, the height of the support cover is greater than the height of the pole extending out of the shell in the Z direction, and the inner surface and / or the outer surface of the support cover is provided with a convex rib. The height of the support cover in the Z direction is greater than the height of the pole extending out of the shell, when the upper surface of the battery cell is impacted by external force, the support cover can preferentially bear the impact load, and the pole is prevented from being directly impacted to be bent and inclined.

Description

Technical Field

[0001] This invention relates to the field of battery technology, specifically to a battery cell and battery pack. Background Technology

[0002] To enable the normal charging and discharging function of the battery cell (i.e., the storage and release of electrical energy), existing technologies typically require terminals as current conduction components between the battery cell and the external circuit. Furthermore, to facilitate the connection between the terminals and the external circuit, a portion of the terminal extends outward along the height of the battery cell, forming a connection segment of suitable length. This connection segment can be connected to the external circuit components through welding, bolting, or other methods to ensure a smooth current conduction path.

[0003] However, during the use of the battery cell, if the upper surface of the cell is impacted by an external force in the height direction, the terminal post is very likely to bend or tilt, thus forming an unexpected electrical connection, which greatly increases the risk of short circuit in the battery cell. Summary of the Invention

[0004] This invention provides a battery cell and battery pack to solve the problem that when the upper surface of the battery cell is impacted by external force, the terminal post is prone to contact with the battery cell casing due to structural failure, which in turn causes a short circuit in the battery cell.

[0005] In a first aspect, the present invention provides a battery cell, comprising:

[0006] The housing has mounting holes on its upper end face along the Z direction;

[0007] The pole post passes through the mounting hole and partially extends out of the upper end face of the housing;

[0008] A support cover is connected to the upper end face of the housing and spaced apart from the pole post. Along the Z direction, the height of the support cover is greater than the height of the pole post extending out of the housing. The inner and / or outer surfaces of the support cover are provided with raised ribs.

[0009] Beneficial effects: This invention increases the height of the support cover along the Z-direction by more than the height of the electrode post extending out of the housing. This provides additional physical protection for the electrode post, preventing it from directly bearing the force in the Z-direction, reducing the probability of electrode post deformation and damage, and improving the overall structural reliability and safety of the battery cell. Secondly, by adding ribs to the outer surface of the support cover, the structural strength of the support cover itself is increased, ensuring structural stability under significant external forces and guaranteeing continuous protection for the electrode post.

[0010] In one optional embodiment, the number of the protruding ribs is n, where n is a positive integer not less than 1, the n protruding ribs are spaced apart along the Y direction, and any one of the protruding ribs extends along the X direction.

[0011] Beneficial effects: The present invention arranges n (n≥1) protruding ribs at intervals along the Y direction and all extending along the X direction. This can not only evenly distribute the impact load on the support cover when it is subjected to force in the Z direction through the regular arrangement, avoiding local stress concentration that could lead to deformation or damage to the support cover, but also further strengthen the structural rigidity of the support cover in the XY plane through the extension direction and arrangement logic of the protruding ribs. This ensures that the support cover remains stable when subjected to external impact and provides reliable physical protection for the pole. At the same time, this arrangement does not affect the assembly relationship between the support cover, the shell, and the pole, balancing structural reinforcement and assembly convenience, and further improving the impact resistance and safety of the battery cell.

[0012] In one optional embodiment, the support cover includes a support plate and a side plate surrounding the support plate. Along the Z direction, the position of the support plate is higher than the position of the top of the pole post. The side plate is connected to the housing. A plurality of the ribs are distributed on the outer surface of the side plate and / or the support plate.

[0013] Beneficial effects: By designing the support cover as a combination of a support plate and peripheral side plates, the stable connection between the side plates and the shell ensures the overall assembly reliability of the support cover, preventing it from falling off or shifting under external impact. The support plate and side plates are equipped with raised ribs, which strengthen the entire surface structure of the support cover. This not only improves the support plate's resistance to deformation under direct Z-axis impact, but also enhances the tear resistance at the connection between the side plates and the shell, preventing local structural failure from causing protection interruption. At the same time, this structure takes into account the assembly stability of the support cover and the impact resistance performance of the entire area, without interfering with the normal layout and function of the poles. It further improves the comprehensive protection of the battery cell against external impact while simplifying the assembly process, ensuring the safety of battery cell use and structural durability.

[0014] In one optional embodiment, the distance between the rib near its Y-direction edge on the support plate and the edge in the Y-direction is D, and the thickness of the support plate in the Z-direction is T, wherein the relationship between D and T satisfies 0.5×T≤D≤2×T.

[0015] Beneficial effects: Limiting the distance D between the ribs on the support plate near its Y-direction edge and that edge in the Y-direction to 0.5 to 2 times its Z-direction thickness T avoids insufficient structural strength and easy cracking of the edge area due to the ribs being too close to the edge (D too small), while preventing the edge area from lacking effective reinforcement and weakening its resistance to deformation due to the ribs being too far from the edge (D too large). Through the matching relationship between D and T, it is ensured that the ribs at the edge can accurately reinforce the weak areas of the support plate, and work together with the ribs in other locations to improve the overall impact resistance of the support cover. At the same time, this ratio range takes into account the structural compactness and material utilization of the support cover, avoiding the impact on the overall layout of the battery cells or the increase of unnecessary costs due to unreasonable size design, and further optimizing the balance between protection effect and practicality.

[0016] In one optional embodiment, the thickness T of the support plate is equal to the thickness of the side plate, and the value of T is in the range of 1.5 mm ≤ T ≤ 2.5 mm.

[0017] Beneficial effects: This invention sets the thickness T of the support plate to be consistent with the thickness of the side plate, and limits T to a reasonable range of 1.5mm to 2.5mm. On the one hand, it can ensure that the overall structure of the support cover is subjected to balanced forces, avoid stress concentration caused by thickness differences in different parts, improve the overall impact resistance and deformation resistance of the support cover, and ensure stable protection of the pole. On the other hand, this thickness range not only meets the structural strength required by the support cover, which can effectively resist external impacts without failure, but also avoids increasing the overall volume and weight of the battery cell due to excessive thickness, affecting assembly compatibility, or causing insufficient protection performance due to insufficient thickness. At the same time, the uniform thickness design can also simplify the processing technology of the support cover, reduce production difficulty and cost, and take into account the reliability of protection, structural compactness and production practicality.

[0018] In one optional embodiment, along the Z direction, the height of the rib on the support plate is h, and the value of h is in the range of 0.2×T≤h≤T; the height of the rib on the support plate is equal to the height of the rib on the side plate.

[0019] Beneficial effects: This invention limits the height h of the ribs on the support plate to 0.2 to 1 times the thickness T of the support cover, and keeps it consistent with the height of the ribs on the side plate. This ensures that the ribs have sufficient height to effectively expand the heat dissipation contact area and improve heat exchange efficiency, while avoiding the increase in the overall volume of the support cover due to excessive h, which would affect the compatibility of cell assembly, or the weakening of structural reinforcement and heat dissipation effect due to insufficient h. At the same time, the uniform rib height design can make the support cover uniformly stressed and heat dissipated evenly, avoiding stress concentration or heat dissipation dead zones in local areas due to differences in rib height. This further enhances the structural stability and heat dissipation reliability of the support cover. Without increasing the design complexity, it takes into account structural protection, heat dissipation efficiency and assembly practicality, providing more comprehensive protection for the pole.

[0020] In one optional embodiment, along the Y direction, the width of the rib is a, and the value of a ranges from 0.6mm ≤ a ≤ 2.5mm; the total width of the n ribs is n×a, the width of the support plate in the Y direction is W1, and the sum of the heights of a pair of side plates located in the Y direction of the support plate in the Z direction is W2. The relationship between n×a, W1, and W2 satisfies: 8% ≤ n×a / (W1+W2) ≤ 40%.

[0021] Beneficial effects: Limiting the rib width 'a' to a reasonable range of 0.6mm to 2.5mm ensures sufficient structural strength for the support cover to withstand impacts, while avoiding excessive space occupation or unnecessary weight due to excessive width. Furthermore, by limiting the ratio of the total width of the n ribs (n×a) to the Y-axis width (W1) of the support plate and the Z-axis height (W2) of both side plates to between 8% and 40%, the total rib coverage meets the overall reinforcement requirements of the support cover, preventing localized failure by evenly distributing external forces. It also prevents material waste and structural redundancy due to overly dense rib layout, or failure to achieve the desired reinforcement effect due to overly sparse layout. This design achieves a precise balance between rib reinforcement effect, structural compactness, and material utilization, while adapting to the overall structural dimensions of the support cover without affecting cell assembly compatibility, further improving the structural reliability and production economy of the cell.

[0022] In one optional embodiment, the sum of the outer surface areas of the n ribs is S0, the outer surface area of ​​the support cover is S, and the relationship between S0 and S satisfies 3%≤S0 / S≤25%; and / or, the interval between two adjacent ribs in the Y direction is b, and the value of b is 1.5mm≤b≤3mm.

[0023] Beneficial effects: By limiting the ratio of the total outer surface area S0 of the ribs to the outer surface area S of the support cover to between 3% and 25%, it ensures that the coverage of the ribs is sufficient to effectively enhance the overall structural strength of the support cover, avoiding insufficient reinforcement due to a low ratio, while preventing material redundancy, increased weight, or impact on other functional layouts of the support cover surface due to a high ratio. Simultaneously, limiting the spacing b between adjacent ribs in the Y direction to 1.5mm to 3mm ensures uniform rib distribution, avoiding stress concentration and weakening of the support cover's base structure due to excessively small spacing, while also preventing localized areas from lacking reinforcement and reducing impact resistance due to excessively large spacing. The combination of these two methods achieves efficient reinforcement of the support cover by the ribs while also considering structural lightweighting and layout rationality, further improving the stability of the support cover under external impact, providing continuous and reliable protection for the pole, and optimizing material utilization and processing convenience in production.

[0024] In one optional embodiment, the upper end face of the housing is provided with a through hole spaced apart from the mounting hole, the support cover is provided outside the through hole, the lower end of the housing is provided with an opening, the battery cell further includes an electrode assembly and a connecting piece, the electrode assembly is disposed in the housing through the opening, the electrode assembly is provided with an electrode tab on the side of the electrode assembly near the upper end face of the housing, and at least a portion of the electrode tab facing the through hole is projected onto the through hole in the XY plane; one end of the connecting piece is connected to the portion of the electrode post located in the housing, and the other end extends to the through hole and is electrically connected to the electrode tab.

[0025] Beneficial effects: When connecting the electrode tab and the connecting piece of the battery cell provided by this invention, the connection can be directly operated through the pre-set through hole on the upper end face of the housing without disassembling or damaging the overall structure of the housing. This greatly simplifies the connection process between the electrode tab and the connecting piece, reduces the difficulty of production operations and the risk of damage during battery cell assembly. At the same time, after the connection is completed, the through hole is sealed by the support cover, which can effectively prevent external dust, moisture and other impurities from entering the housing, avoid corrosion or oxidation of the welded parts due to contact with impurities, and ensure the stability and durability of the electrical connection between the connecting piece and the electrode tab.

[0026] Secondly, the present invention also provides a battery pack, comprising:

[0027] Box;

[0028] Multiple of the aforementioned battery cells are arranged side-by-side along the Y direction inside the housing;

[0029] A busbar, located inside the housing and connecting the terminals between two adjacent cells, wherein the two terminals connected by the busbar have opposite polarities;

[0030] Along the Z direction, the highest point of the busbar is lower than the highest point of the support cover.

[0031] Beneficial effects: By limiting the highest point of the busbar to be lower than the highest point of the support cover along the Z direction, the support cover can provide physical protection for the busbar, preventing external impacts from acting directly on the busbar and being transmitted to the terminals, thus avoiding deformation of the terminals. This improves the structural reliability and safety of the battery pack and extends its overall service life. Attached Figure Description

[0032] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of a battery cell according to an embodiment of the present invention;

[0034] Figure 2 for Figure 1 The diagram shows the structure of the battery cell without the support cover.

[0035] Figure 3 for Figure 1 A cross-sectional schematic diagram of the battery cell shown.

[0036] Figure 4 for Figure 1 A schematic diagram of the structure of the shell shown;

[0037] Figure 5 for Figure 1 Schematic diagram of the structure of the central support cover;

[0038] Figure 6 for Figure 5 Cross-sectional view from the perspective of AA.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1. Housing; 101. Opening; 102. Upper end face; 1021. Mounting hole; 1022. Through hole; 103. Cover plate; 2. Pole post; 3. Support cover; 301. Support plate; 302. Side plate; 303. Liquid injection hole; 4. Rib; 5. Pole assembly; 501. Pole lug; 6. Connecting piece; 7. Insulating component; 701. Connecting port; 702. Protrusion; 7021. Cavity. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] To address the problem that when an external force impacts the upper surface of a battery cell, the terminal post may easily come into contact with the cell casing due to structural failure, thereby causing a short circuit in the cell, this invention provides a battery cell and a battery pack.

[0043] The following is combined with Figures 1 to 6 The embodiments of the present invention are described below. For ease of description thereafter, as follows... Figure 1 As shown, a spatial rectangular coordinate system is established: the height direction of the battery cell is denoted as the Z direction, the length direction of the battery cell is denoted as the X direction, and the width direction of the battery cell is denoted as the Y direction.

[0044] According to embodiments of the present invention, in one aspect, such as Figure 1 , Figure 5 as well as Figure 6 As shown, a battery cell is provided, including: a housing 1, a terminal post 2, and a support cover 3.

[0045] Specifically, along the Z direction, the upper end face 102 of the housing 1 is provided with a mounting hole 1021; the pole post 2 passes through the mounting hole 1021 and partially extends out of the upper end face 102 of the housing 1; the support cover 3 is connected to the upper end face 102 of the housing 1 and is spaced apart from the pole post 2, and along the Z direction, the height of the support cover 3 is greater than the height of the pole post 2 extending out of the housing 1; the inner surface and / or outer surface of the support cover 3 are provided with ribs 4.

[0046] In this embodiment of the invention, the height of the support cover 3 along the Z-direction is greater than the height of the electrode post 2 extending out of the housing 1. This allows the support cover 3 to provide additional physical protection for the electrode post 2, preventing the electrode post 2 from directly bearing the force in the Z-direction, reducing the probability of deformation and damage to the electrode post 2, and improving the overall structural reliability and safety of the battery cell. Secondly, by providing protruding ribs 4 on the outer surface of the support cover 3, the structural strength of the support cover 3 itself can be increased, enabling it to maintain structural stability under large external forces and ensuring continuous protection for the electrode post 2.

[0047] In one embodiment, such as Figure 1 , Figure 5 as well as Figure 6 As shown, there are n ribs 4, where n is a positive integer not less than 1. The n ribs 4 are spaced apart along the Y direction, and any one of the ribs 4 extends along the X direction. It can be understood that in this embodiment of the invention, the n (n≥1) ribs 4 are arranged spaced apart along the Y direction and all extend along the X direction. This can not only evenly distribute the impact load on the support cover 3 when it is subjected to force in the Z direction through a regular arrangement, avoiding local stress concentration that could lead to deformation or damage to the support cover 3, but also further strengthen the structural rigidity of the support cover 3 in the XY plane through the extension direction and arrangement logic of the ribs 4. This ensures that the support cover 3 remains stable when subjected to external impact, continuously providing reliable physical protection for the pole post 2. At the same time, this arrangement does not affect the assembly relationship between the support cover 3 and the shell 1 and the pole post 2, taking into account both structural reinforcement and assembly convenience, and further improving the impact resistance and safety of the battery cell.

[0048] In one embodiment, such as Figure 1 , Figure 5 as well as Figure 6 As shown, the support cover 3 includes a support plate 301 and a side plate 302 surrounding the support plate 301. Along the Z direction, the position of the support plate 301 is higher than the position of the top of the pole post 2. The side plate 302 is connected to the shell 1. Multiple ribs 4 are distributed on the outer surface of the side plate 302 and / or the support plate 301. It is understandable that by setting the support cover 3 as a combination of the support plate 301 and the peripheral side plate 302, the side plate 302 is firmly connected to the shell 1, which can ensure the overall assembly reliability of the support cover 3 and ensure that it will not fall off or shift under external impact. The support plate 301 and the side plate 302 are both distributed with ribs 4, which can realize the full surface structure reinforcement of the support cover 3. This not only improves the deformation resistance of the support plate 301 to withstand direct Z-direction impact, but also enhances the tear resistance of the connection between the side plate 302 and the shell 1, avoiding the interruption of protection due to local structural failure. At the same time, this structure takes into account the assembly stability of the support cover 3 and the impact resistance performance of the whole area, without interfering with the normal layout and function of the pole post 2. On the basis of simplifying the assembly process, it further improves the comprehensive protection of the cell against external impact, ensuring the safety of the cell and the durability of the structure.

[0049] It should be noted that in this embodiment, raised ribs 4 are provided on the outer surface of the support cover 3. This not only enhances the structural strength of the support cover 3 but also effectively improves its heat dissipation capacity. The specific reasons are as follows: the raised ribs 4 increase the total surface area of ​​the support cover 3. Compared to a flat surface, the uneven structure formed by the raised ribs 4 expands the contact area with the outside environment. Therefore, the contact area between the support cover 3 and the thermally conductive adhesive can increase by 3% to 25%. Thus, during the battery cell cycling process, the temperature rise of the outer surface of the support cover 3 can be controlled below 60°C (current technology typically operates between 65°C and 75°C), and the fast-charging capability of the battery cell can be improved by approximately 10% to 25%.

[0050] In one embodiment, such as Figure 5 As shown, the distance D between the rib 4 near the edge of the support plate 301 in the Y direction and the edge in the Y direction is D, and the thickness T of the support plate 301 in the Z direction is T. The relationship between D and T satisfies 0.5×T≤D≤2×T. It can be understood that limiting the distance D between the rib 4 near the edge of the support plate 301 in the Y direction and the edge in the Y direction to 0.5 to 2 times its thickness T in the Z direction can both prevent the rib 4 from being too close to the edge (D is too small) and causing insufficient structural strength at the edge, making it easy to crack under impact, and prevent the rib 4 from being too far from the edge (D is too large) and causing the edge area to lack effective reinforcement and weaken its resistance to deformation. Through the matching relationship between D and T, it is ensured that the rib 4 at the edge can accurately reinforce the weak area of ​​the support plate 301, and work together with the ribs 4 in other positions to improve the overall impact resistance of the support cover 3. At the same time, this ratio range takes into account the structural compactness and material utilization of the support cover 3, avoiding the impact on the overall layout of the battery cell or the increase of unnecessary costs due to unreasonable size design, and further optimizing the balance between protection effect and practicality.

[0051] It is understandable that the range of values ​​for D can be, but is not limited to, 0.5×T, 0.6×T, 0.75×T, 0.8×T, 0.9×T, T, 1.1×T, 1.2×T, 1.3×T, 1.4×T, 1.5×T, 1.6×T, 1.7×T, 1.8×T, 1.9×T, 2×T, or any value between the two.

[0052] In one embodiment, such as Figure 6As shown, the thickness T of the support plate 301 is equal to the thickness of the side plate 302, and the value of T ranges from 1.5mm to 2.5mm. It can be understood that in this embodiment of the invention, the thickness T of the support plate 301 and the side plate 302 are set to be consistent, and T is limited to a reasonable range of 1.5mm to 2.5mm. On the one hand, this ensures that the overall structure of the support cover 3 is subjected to balanced forces, avoiding stress concentration due to thickness differences in different parts, improving the overall impact and deformation resistance of the support cover 3, and ensuring stable protection of the pole post 2. On the other hand, this thickness range satisfies the structural strength required by the support cover 3, effectively resisting external impacts without failure, while avoiding excessive thickness increasing the overall volume and weight of the battery cell and affecting assembly compatibility, or insufficient thickness leading to inadequate protection performance. Furthermore, the uniform thickness design simplifies the processing technology of the support cover 3, reduces production difficulty and cost, and balances protection reliability, structural compactness, and production practicality.

[0053] It is understood that the value of T can be, but is not limited to, 1.5mm, 1.6mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm or any value between two of these.

[0054] In one embodiment, such as Figure 6 As shown, along the Z direction, the height of the rib 4 on the support plate 301 is h, and the value of h ranges from 0.2×T≤h≤T. The height of the rib 4 on the support plate 301 is equal to the height of the rib 4 on the side plate 302. It can be understood that in this embodiment of the invention, the height h of the rib 4 on the support plate 301 is limited to 0.2 to 1 times the thickness T of the support cover 3, and is consistent with the height of the rib 4 on the side plate 302. This ensures that the rib 4 has sufficient height to effectively expand the heat dissipation contact area and improve heat exchange efficiency, while avoiding the increase in the overall volume of the support cover 3 due to excessive h, which would affect the compatibility of cell assembly, or the weakening of structural reinforcement and heat dissipation effect due to excessively small h. At the same time, the uniform design of the rib 4 height can make the support cover 3 uniformly stressed and evenly dissipate heat, avoiding stress concentration or heat dissipation dead corners in local areas due to differences in the height of the rib 4. This further enhances the structural stability and heat dissipation reliability of the support cover 3. Without increasing the design complexity, it takes into account structural protection, heat dissipation efficiency and assembly practicality, providing more comprehensive protection for the pole 2.

[0055] It is understandable that the range of values ​​for h can be, but is not limited to, 0.2×T, 0.3×T, 0.4×T, 0.5×T, 0.6×T, 0.75×T, 0.8×T, 0.9×T, T, or any value between the two.

[0056] In one embodiment, such as Figure 5 and Figure 6As shown, along the Y direction, the width of the rib 4 is a, and the value of a is 0.6mm≤a≤2.5mm; the total width of the n ribs 4 is n×a, the width of the support plate 301 in the Y direction is W1, and the height of a pair of side plates 302 located in the Y direction of the support plate in the Z direction is W2. The relationship between n×a, W1 and W2 satisfies: 8%≤n×a / (W1+W2)≤40%. It is understandable that limiting the width 'a' of the protruding ribs 4 to a reasonable range of 0.6mm to 2.5mm ensures that the ribs 4 themselves possess sufficient structural strength to enhance the impact resistance of the support cover 3, while avoiding excessive space occupation or unnecessary weight addition due to excessive width. Simultaneously, by limiting the ratio of the total width of the n protruding ribs 4 (n×a) to the width of the support plate in the Y direction (W1) and the sum of the heights of the two side plates in the Z direction (W2) to between 8% and 40%, it ensures that the total coverage of the protruding ribs 4 meets the overall reinforcement requirements of the support cover 3, preventing localized failure by evenly distributing external forces. It also prevents the ribs 4 from being too dense, leading to material waste and structural redundancy, or too sparse, failing to achieve the expected reinforcement effect. This design achieves a precise balance between the reinforcement effect of the protruding ribs 4, structural compactness, and material utilization, while also adapting to the overall structural dimensions of the support cover 3, without affecting the compatibility of the battery cell assembly, further improving the structural reliability and production economy of the battery cell.

[0057] It is understood that the value of 'a' can be, but is not limited to, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.6mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, or any value between two of these. Similarly, the value of 'n×a / (W1+W2)' can be, but is not limited to, 8%, 9%, 10%, 12%, 15%, 16%, 18%, 20%, 25%, 26%, 28%, 29%, 30%, 32%, 34%, 36%, 39%, 40%, or any value between two of these.

[0058] In one embodiment, the sum of the outer surface areas of the n protrusions 4 is S0, and the outer surface area of ​​the support cover 3 is S. The relationship between S0 and S satisfies 3% ≤ S0 / S ≤ 25%; and / or, the interval between two adjacent protrusions 4 in the Y direction is b, where b ranges from 1.5mm ≤ b ≤ 3mm. It can be understood that by limiting the ratio of the total outer surface area S0 of the protrusions 4 to the outer surface area S of the support cover 3 to between 3% and 25%, it ensures that the coverage of the protrusions 4 is sufficient to effectively enhance the overall structural strength of the support cover 3, avoiding insufficient reinforcement due to a low proportion, while also preventing excessively high proportions from causing material redundancy, increased weight, or affecting other functional layouts on the surface of the support cover 3. Simultaneously, limiting the interval b between adjacent protrusions 4 in the Y direction to between 1.5mm and 3mm ensures that the protrusions 4 are evenly distributed, avoiding stress concentration and weakening of the support cover 3's base structure due to excessively small intervals, while also preventing excessively large intervals from causing a lack of protrusion reinforcement in local areas and a decrease in impact resistance. The combination of the two achieves efficient reinforcement of the support cover 3 by the rib 4, while also taking into account the lightweight structure and reasonable layout, further improving the stability of the support cover 3 when subjected to external impact, providing continuous and reliable protection for the pole 2, and optimizing the material utilization rate and processing convenience in production.

[0059] It is understood that the value range of S0 / S can be, but is not limited to, 3%, 4%, 6%, 8%, 9%, 10%, 12%, 15%, 16%, 18%, 20%, 25%, or any value between two of these. Similarly, the value range of b can be, but is not limited to, 1.5mm, 1.6mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, or any value between two of these.

[0060] In one embodiment, such as Figure 2 and Figure 3As shown, the upper end face 102 of the housing 1 is provided with a through hole 1022 spaced apart from the mounting hole 1021. The support cover 3 is provided outside the through hole 1022. The lower end of the housing 1 is provided with an opening 101. The battery cell also includes an electrode group 5 and a connecting piece 6. The electrode group 5 is disposed inside the housing 1 through the opening 101. The electrode group 5 is provided with an electrode tab 501 on the side near the upper end face 102 of the housing 1. On the XY plane, the orthographic projection of the electrode tab 501 toward the through hole 1022 is at least partially located within the range of the through hole 1022. One end of the connecting piece 6 is connected to the part of the pole post 2 located inside the housing 1, and the other end extends to the through hole 1022 and is electrically connected to the electrode tab 501. It is understood that when the battery cell provided in this embodiment of the invention is connected to the tab 501 and the connecting piece 6, it can be directly operated through the through hole 1022 preset on the upper end face 102 of the housing 1 without disassembling or damaging the overall structure of the housing 1. This greatly simplifies the connection process between the tab 501 and the connecting piece 6, reduces the difficulty of production operation and the risk of damage during battery cell assembly. At the same time, after the connection is completed, the through hole 1022 is sealed by the support cover 3, which can effectively prevent external dust, moisture and other impurities from entering the housing 1, avoid corrosion or oxidation of the welding part due to contact with impurities, and ensure the stability and durability of the electrical connection between the connecting piece 6 and the tab 501.

[0061] It should be noted that, generally, the casing typically has a mounting port for the electrode assembly at its upper Z-axis position, which is then sealed by welding. However, due to the relatively low connection strength at the weld, when the cell cover assembly is subjected to a force in the Z-axis direction, the connection between the cell cover assembly and the casing may bear the impact, leading to cracking, detachment, and other failures at the weld. Therefore, if... Figure 3 As shown, in this embodiment, the opening 101 is set at the lower end of the housing 1, which means that the upper end surface 102 of the housing 1 is integrally formed with the side wall of the housing 1, thereby improving the overall structural strength and impact resistance of the upper end of the housing 1.

[0062] It is understandable that, in order to ensure the airtightness of the inside of the cell housing 1, after the assembly of internal components such as the electrode group 5 is completed, such as... Figure 4 As shown, the opening 101 also needs to be sealed using the cover plate 103.

[0063] It should be noted that in this embodiment, the connecting piece 6 and the tab 501 can be connected together by welding or by conductive adhesive, as long as the current can flow normally between them. This invention does not impose any special limitations on this.

[0064] Furthermore, in this embodiment, one end of the connecting piece 6 is extended to the through hole 1022 and electrically connected to the tab 501 there. This can improve the internal space utilization of the battery, reduce the welding of the connecting piece 6 to the electrode group 5 and the bending process of the connecting piece 6, and improve production efficiency. The specific reasons are as follows: Currently, when the battery cell uses the connecting piece 6 to connect the terminal post 2 and the tab 501, both the connecting piece 6 and the tab 501 need to be bent. Moreover, the connecting piece 6, the terminal post 2 and the tab 501 are usually located on the same vertical plane, thus requiring a large thickness space, resulting in low internal space utilization of the battery cell.

[0065] In one embodiment, at least a portion of the connecting piece 6 and the tab 501 extends into the through hole 1022, and the tab 501 is welded to the connecting piece 6 near the upper end face 102 of the housing 1. It can be understood that extending at least a portion of the connecting piece 6 and the tab 501 into the through hole 1022 in this embodiment facilitates the connection operation and reduces operational difficulty; furthermore, it allows the connection point to be closer to the housing 1, improving subsequent heat dissipation. In addition, the direct welding of the connecting piece 6 to the terminal post 2 reduces the internal resistance of the battery cell, lowers the temperature rise of the battery cell, and improves the fast charging performance of the battery cell.

[0066] In one embodiment, an insulating element 7 is provided between the connection point of the connecting piece 6 and the tab 501 and the support cover 3. It can be understood that by providing an insulating element 7 between the connection point of the connecting piece 6 and the tab 501 and the support cover 3, this embodiment can prevent direct contact between the support cover 3 and the connection point of the connecting piece 6 and the tab 501, thus preventing risks such as internal arcing and creepage.

[0067] Specifically, the shape of the insulating element 7 is adapted to the shape of the support cover 3, and the two can be connected by heat fusion.

[0068] In one embodiment, such as Figure 1 , Figures 5 to 6 As shown, the support cover 3 also has an injection hole 303, and the insulating component 7 has a connecting port 701 that connects the injection hole 303 to the interior of the housing 1. It can be understood that in this embodiment, the injection hole 303 is provided on the support cover 3, and the corresponding connecting port 701 is provided on the insulating component 7, so that the injection hole 303 and the interior of the housing 1 form a through channel. Electrolyte (or other required media) can be accurately injected directly into the interior of the housing 1 through the injection hole 303 without disassembling the assembly structure of the support cover 3 and the insulating component 7, simplifying the injection operation process and improving injection efficiency. At the same time, the connecting port 701 ensures a smooth injection path, avoiding media overflow or uneven injection. After injection, the injection hole 303 can be specifically sealed without affecting the original positioning connection effect of the support cover 3 and the insulating component 7, balancing the convenience of injection with the sealing performance and insulation stability of the overall structure, ensuring the reliability of the battery cell assembly and use.

[0069] Furthermore, the insulating member 7 is also provided with a protrusion 702 extending toward the electrode group 5. The protrusion 702 abuts against the upper surface of the electrode group 5 or the connection between the electrode tab 501 and the connecting piece 6. The protrusion 702 has a cavity 7021 inside that communicates with the liquid injection hole 303 and the communication port 701. The communication port 701 is formed at one end of the protrusion 702 near the electrode group 5. This configuration allows the insulating component 7 to be more stably positioned within the housing 1, ensuring that the connecting port 701 is always precisely aligned and tightly connected with the injection hole 303. This avoids leakage or overflow of electrolyte due to channel misalignment during the injection process, and allows the electrolyte to be directly delivered to the designated area inside the housing 1 through the injection hole 303, cavity 7021, and connecting port 701. This ensures that the electrolyte quickly wets the key areas, improves injection efficiency and the uniformity of electrolyte distribution inside the battery. At the same time, the abutting action of the protrusion 702 can also provide auxiliary positioning for the electrode assembly 5, reducing displacement of the electrode assembly 5 during battery assembly or use, and ensuring the stability of the cell structure and the consistency of electrical performance.

[0070] Furthermore, in order to improve the structural strength of the insulating component 7, a reinforcing rib structure can be provided on the insulating component 7.

[0071] According to an embodiment of the present invention, another aspect provides a battery pack, including: a housing, a plurality of the above-described battery cells, and a busbar.

[0072] Specifically, multiple of the aforementioned battery cells are arranged side by side in the housing along the Y direction; a busbar is located in the housing and connects the terminals 2 between two adjacent battery cells, and the polarities of the two terminals 2 connected by the busbar are opposite; the highest point of the busbar along the Z direction is lower than the highest point of the support cover 3.

[0073] The highest point of the busbar is limited to be lower than the highest point of the support cover 5 along the Z direction. The support cover 3 can form physical protection for the busbar, preventing external impacts from acting directly on the busbar and being transmitted to the terminal 2, which would cause the terminal 2 to deform. This improves the structural reliability and safety of the battery pack and extends its overall service life.

[0074] The technical effects of the present invention will be described below with reference to some embodiments and comparative examples.

[0075] Table 1

[0076]

[0077] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that, include: The housing has mounting holes on its upper end face along the Z direction; The pole post passes through the mounting hole and partially extends out of the upper end face of the housing; A support cover is connected to the upper end face of the housing and spaced apart from the pole post. Along the Z direction, the height of the support cover is greater than the height of the pole post extending out of the housing. The outer surface of the support cover is provided with raised ribs. The number of the protruding ribs is n, where n is a positive integer not less than 1. The n protruding ribs are spaced apart along the Y direction, and any one of the protruding ribs extends along the X direction. The support cover includes a support plate and a side plate surrounding the support plate. Along the Z direction, the position of the support plate is higher than the position of the top of the pole post. The side plate is connected to the housing. A plurality of the ribs are distributed on the outer surface of the side plate and / or the support plate. Along the Y direction, the width of the rib is a, and the value of a ranges from 0.6mm ≤ a ≤ 2.5mm; the total width of the n ribs is n×a; the width of the support plate in the Y direction is W1; the sum of the heights of a pair of side plates located in the Y direction of the support plate in the Z direction is W2; and the relationship between n×a, W1, and W2 satisfies: 8% ≤ n×a / (W1+W2) ≤ 40%. The sum of the outer surface areas of the n protruding ribs is S0, and the outer surface area of ​​the support cover is S. The relationship between S0 and S satisfies 3%≤S0 / S≤25%. The interval between two adjacent protruding ribs in the Y direction is b, and the value of b is 1.5mm≤b≤3mm.

2. The battery cell according to claim 1, characterized in that, The distance between the rib near the edge of the support plate in the Y direction and the edge in the Y direction is D, and the thickness of the support plate in the Z direction is T. The relationship between D and T satisfies: 0.5×T≤D≤2×T.

3. The battery cell according to claim 2, characterized in that, The thickness T of the support plate is equal to the thickness of the side plate, and the value of T is in the range of 1.5 mm ≤ T ≤ 2.5 mm.

4. The battery cell according to claim 3, characterized in that, Along the Z direction, the height of the rib on the support plate is h, and the value of h is in the range of 0.2×T≤h≤T; the height of the rib on the support plate is equal to the height of the rib on the side plate.

5. The battery cell according to any one of claims 1 to 4, characterized in that, The upper end face of the housing is provided with a through hole spaced apart from the mounting hole. The support cover is provided outside the through hole. The lower end of the housing is provided with an opening. The battery cell also includes an electrode assembly and a connecting piece. The electrode assembly is disposed in the housing through the opening. The electrode assembly is provided with an electrode tab on the side near the upper end face of the housing. On the XY plane, the orthographic projection of the electrode tab toward the through hole is at least partially located within the range of the through hole. One end of the connecting piece is connected to the portion of the electrode post located inside the housing, and the other end extends to the through hole and is electrically connected to the electrode tab.

6. A battery pack, characterized in that, include: Box; The battery cells according to any one of claims 1 to 5 are arranged side by side in the housing along the Y direction; A busbar, located inside the housing and connecting the terminals between two adjacent battery cells, wherein the two terminals connected by the busbar have opposite polarities; Along the Z direction, the highest point of the busbar is lower than the highest point of the support cover.

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