A single cell upper cover assembly, a single cell, and a battery member

Abstract

The utility model belongs to the battery field, concretely is a kind of upper cover subassembly for single battery, single battery and battery component.Single battery includes upper cover subassembly, and battery component includes multiple single batteries, and upper cover subassembly includes upper cover plate, and the side wall of upper cover plate is equipped with first concave-convex structure, for with the mutual embedding of the glue layer that is covered in single battery cylinder and upper cover plate side wall, form interlock, by the adhesion of glue layer and the mechanical bite cooperation of interlock structure, the installation stability of single battery in box is significantly improved.

Description

Technical Field

[0001] This utility model belongs to the field of batteries, specifically a cover assembly for a single battery, a single battery, and a battery component. Background Technology

[0002] In a battery pack, individual cells are typically arranged closely together inside the casing. During everyday use, the battery pack is inevitably subjected to vibration or impact. If the individual cells are not very stable, they may collide with each other inside the casing.

[0003] In the event of a collision, the most direct consequence is damage to the casing of a single battery cell, breaking its original good seal and allowing external moisture, dust, and other impurities to enter. Once inside the battery, these impurities gradually corrode key components such as the electrolyte and electrodes, disrupting the originally stable chemical reaction environment inside the battery and directly interfering with its electrical performance.

[0004] Meanwhile, collisions can also trigger more serious internal problems. Due to the vibration and impact, the electrode materials and separators inside a single battery cell are highly susceptible to displacement or damage. Key parameters that play a decisive role in the electrochemical reaction, such as the contact area and spacing between electrodes, change accordingly, causing a sharp decline in the efficiency of the electrochemical reaction and making the battery's charge and discharge performance extremely unstable. As a result, individual batteries cannot operate collaboratively as they would under normal conditions, ultimately affecting the stability and reliability of the entire battery pack, causing numerous inconveniences and even potential safety hazards for users. Summary of the Invention

[0005] The purpose of this invention is to provide a cover assembly for a single battery, a single battery, and a battery component, overcoming the technical problem of poor installation stability of individual batteries in existing battery packs.

[0006] The first aspect of this utility model provides a top cover assembly for a single battery cell, used to seal the open end of the top of the single battery cell, including a top cover plate and polar terminals fixed thereon; the side wall of the top cover plate is provided with a first concave-convex structure for interlocking with an adhesive layer covering the side wall of the top cover plate to form an interlock.

[0007] This invention improves the stability of individual cells within the battery pack by injecting adhesive into the battery pack housing. The adhesive penetrates between individual cells and into the gaps between individual cells and the housing.

[0008] To further enhance the bonding strength between the adhesive layer and each individual battery cell, this invention incorporates a first concave-convex structure on the side wall of the top cover. This structure, when interlocked with the adhesive layer, significantly improves the installation stability of the individual battery cells within the casing through the adhesive force of the adhesive layer and the mechanical engagement of the interlocking structure.

[0009] Furthermore, the aforementioned first concave-convex structure is a stepped structure, an annular groove, or an annular boss that extends circumferentially along the side wall of the upper cover plate.

[0010] Firstly, the first concave-convex structure extends circumferentially along the top cover plate, enabling the adhesive layer to fully adhere and fit with the sidewall of the top cover plate. Compared to local structures, this maximizes the contact area and makes the adhesive force distribution more uniform. Secondly, the step, groove, or boss structure is easy to process and can be integrally formed with the top cover plate without the need for additional assembly parts. This reduces the complexity of the production process and ensures the integrity and stability of the structure.

[0011] Furthermore, the surface of the upper cover plate facing the inner cavity of the cylinder is provided with a protruding structure. When the upper cover assembly seals the open end of the top of the single battery cylinder, the protruding structure presses against the top of the electrode assembly inside the cylinder.

[0012] The above-mentioned protruding structure has at least the following two functions: Firstly, it provides a safety gap between the top cover and the top of the electrode assembly. This gap provides space for the tabs or connectors used to connect the polarity terminals to the tabs when the top cover assembly is sealed and assembled with the cylinder. This effectively prevents the tabs or connectors from being excessively bent or squeezed due to insufficient space during packaging, thus eliminating the potential risk of internal short circuits. Secondly, the protruding structure applies a pre-tightening force to the electrode assembly, thereby limiting the electrode assembly in the height direction of the battery and preventing it from moving around inside the cylinder.

[0013] A second aspect of the present invention provides a single-cell battery, including a housing and an electrode assembly located in the inner cavity of the housing; the housing includes a cylindrical body with an open top and a top cover assembly sealed at the open top end of the cylindrical body; the top cover assembly is the aforementioned top cover assembly for a single-cell battery.

[0014] Furthermore, the aforementioned cylindrical body is provided with a connector, which is used to connect with the connector of an adjacent individual battery cell.

[0015] Adjacent individual cells can be connected by connectors on the cylinder body, which can quickly and securely connect them. The operation is simple and the connection is reliable, further improving the stability of each individual cell.

[0016] Furthermore, the outer wall of the aforementioned cylinder is provided with a second concave-convex structure, which is used to interlock with the adhesive layer covering the outer wall of the single battery cylinder to form an interlock.

[0017] The second concave-convex structure on the outer wall of the cylinder further expands the contact area between the adhesive layer and the shell, significantly improving the installation stability and structural reliability of the individual battery cells within the pressure tank through dual mechanical interlocking. Furthermore, the first and second concave-convex structures make the connection between the top cover and the cylinder more reliable, reducing the probability of tearing at the connection point when the battery cavity expands due to heat.

[0018] Furthermore, the aforementioned casing is made of plastic, and its strength is P, where P1≤P≤P2; where P1 is the strength requirement of the casing during the formation stage and the normal charging and discharging stage of the battery; and P2 is the strength requirement of the casing during the thermal runaway stage.

[0019] The aforementioned housing serves as a containment cavity for the electrode assembly and electrolyte, providing a sealing function. Simultaneously, the housing strength must meet the strength requirements of the formation stage and the normal charge and discharge stages of the battery. That is, the housing is required to have a certain strength to ensure that it will not crack during the formation stage and the normal charge and discharge stages of the battery, despite changes in the internal environment of the battery, such as temperature and pressure. Compared with existing finished battery housings, this housing has a lower cost, thereby reducing the overall cost of the battery component.

[0020] A third aspect of the present invention provides a battery component, including a pressure-bearing housing and n individual batteries located within the pressure-bearing housing; wherein the individual batteries are the aforementioned individual batteries, and n is an integer greater than 1; an adhesive layer is provided between each individual battery and between each individual battery and the pressure-bearing housing; the adhesive layer and a first concave-convex structure on the side wall of the upper cover plate are interlocked to form an interlock.

[0021] This invention involves injecting adhesive into the pressure-bearing box of the battery pack. The adhesive penetrates between the individual cells and into the gaps between the individual cells and the pressure-bearing box, bonding multiple individual cells into a whole. At the same time, the adhesive layer and the first concave-convex structure of the top cover interlock with each other, significantly improving the installation stability of the individual cells in the box.

[0022] Furthermore, the aforementioned pressure tank meets the compressive strength requirements during the thermal runaway stage, and it is equipped with a venting section. This means the pressure tank must possess sufficient strength to form a robust barrier during thermal runaway, effectively isolating high-temperature flames and harmful gases, preventing the spread of thermal runaway, and improving the safety of the battery pack after thermal runaway.

[0023] Furthermore, the top plate of the enclosure has clearance holes corresponding to the polarity terminals of each individual battery; the area of ​​the top plate of the enclosure corresponding to the clearance holes is fixedly sealed to the individual battery casing; the polarity terminals of each individual battery extend out of the clearance holes.

[0024] Furthermore, the connectors of adjacent individual cells are connected to each other, and the inner cavities of adjacent individual cells are kept open through the connectors, while the inner cavities of the first and last individual cells are kept sealed to the pressure tank.

[0025] In the entire battery assembly, the internal cavities of all individual cells are interconnected, which can effectively improve the differences that may exist between individual cells, ensure the consistency of each individual cell during charging and discharging, extend the overall service life, and improve the performance of the battery assembly.

[0026] The beneficial effects of this utility model are: This invention involves injecting adhesive into the pressure-bearing box of the battery pack. The adhesive penetrates between the individual cells and into the gaps between the individual cells and the pressure-bearing box, bonding multiple individual cells into a whole. At the same time, the adhesive layer and the first concave-convex structure of the top cover interlock with each other, significantly improving the installation stability of the individual cells in the box. Attached Figure Description

[0027] Figure 1 This is a structural schematic diagram of the upper cover assembly from a first-view perspective in Embodiment 1; Figure 2 This is a structural schematic diagram of the upper cover assembly from a second perspective in Embodiment 1; Figure 3 This is a schematic diagram of the structure of a single cell in Example 1; Figure 4 This is a partial structural diagram of the battery component in Example 1; Figure 5 This is a first-view structural diagram of a single battery cell in Example 2; Figure 6 This is a schematic diagram of the second-view structure of a single battery cell in Example 2; Figure 7 This is a partial structural diagram of the battery component in Example 2; Figure 8 This is a schematic diagram of a partial exploded structure of the battery component in Example 2; Figure 9 This is a first-view structural diagram of a single battery cell in Example 4; Figure 10 This is a schematic diagram of the second-view structure of a single battery cell in Example 4; Figure 11 This is a schematic diagram of a partial exploded structure of the battery component in Example 4; Figure 12 This is a partial structural diagram of the battery component in Example 4.

[0028] The attached figures are labeled as follows: 1. Top cover assembly; 11. Top cover plate; 12. Polar terminal; 13. First concave-convex structure; 14. Protruding structure; 15. Second concave-convex structure; 2. Cylinder body; 21. First recess; 22. First boss; 23. Second recess; 24. Second boss; 25. First blind hole; 26. Second blind hole; 3. Single cell battery. Detailed Implementation

[0029] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0030] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0031] In the description of this invention, it should be noted that the terms "top," "bottom," etc., indicating orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Example 1

[0032] like Figure 1 The diagram shown is a structural schematic of the top cover assembly 1 in this embodiment. It is applied to the square lithium-ion single cell battery 3 to seal the open end of the top of the single cell battery 3 cylinder 2. It is mainly composed of a top cover plate 11 and polar terminals 12 fixed thereon.

[0033] The top cover plate 11 has a rectangular plate-like structure, with a first concave-convex structure 13 on its side wall. Here, "side wall" specifically refers to the four vertical surfaces of the top cover plate 11 that are perpendicular to the upper and lower surfaces, and the height of the side wall is the same as the thickness of the top cover plate 11. The core function of the first concave-convex structure 13 is to form a stable bond with the adhesive layer, and its structural form can be flexibly designed according to the actual process and stability requirements.

[0034] It should be noted that in this utility model, each individual battery 3 having the above-mentioned top cover assembly 1 is placed inside the box to form a battery component; the above-mentioned adhesive layer is an adhesive layer located between each individual battery 3 and between each individual battery 3 and the box inside the box. Based on the adhesive layer, the gaps between each individual battery 3 and between the individual battery 3 and the box can be filled, thereby improving the stability of each individual battery 3 inside the box.

[0035] Preferably, the first concave-convex structure 13 is a closed-loop structure that extends continuously along the circumferential direction of the sidewall of the upper cover plate 11. This extension method ensures a full-range, seamless fit with the adhesive layer, avoiding weak points in the corner areas of the rectangular cover plate. Specifically, the first concave-convex structure 13 can be a ring-shaped protrusion, a ring-shaped groove, a step structure extending circumferentially, or a threaded structure along the circumferential direction, or similar concave-convex structures. These structures can achieve engagement with the adhesive layer through mechanical fitting. The first concave-convex structure 13 can also be a rough structure provided on the sidewall of the upper cover plate 11. The rough structure improves the adhesion to the adhesive layer. Specifically, it can be obtained by directly surface treating the sidewall (such as sandblasting, chemical etching, etc.).

[0036] This embodiment takes into account the ease of processing the rectangular top cover plate 11 and its bonding strength with the adhesive layer, and preferably adopts an annular protrusion structure, an annular groove structure, and a stepped structure. Such structures have mature processing technology and can form a continuous closed loop fitting along the circumference of the rectangular cover plate to ensure uniform force distribution in all directions. Figure 1 Taking a single-stage structure as an example, in other embodiments, a multi-stage structure with two or more stages can be used.

[0037] like Figure 2 As shown, in this embodiment, a protruding structure 14 can also be provided on the lower surface of the upper cover plate 11 (the surface facing the inner cavity of the cylinder 2). The protruding structure 14 mainly has the following two functions: First, it provides a safety gap between the upper cover plate 11 and the top of the electrode assembly. This gap can provide a space for the tabs or connectors used to connect the polarity terminals and the tabs when the upper cover assembly 1 and the cylinder 2 are sealed together, effectively avoiding excessive bending or squeezing of the tabs or connectors due to insufficient space during packaging, thus eliminating the potential risk of internal short circuit. Second, the protruding structure 14 applies a pre-tightening force to the electrode assembly, thereby limiting the electrode assembly in the height direction of the battery and preventing it from moving around inside the cylinder 2.

[0038] The protrusion structure 14 is preferably located at the center of the upper cover plate 11. Its specific shape can be a frustum structure or a rib structure as shown in the figure. The core requirement is that its end face is flat and in uniform contact with the electrode assembly.

[0039] like Figure 3The diagram shown is a structural schematic of the single cell 3 in this embodiment, including a housing and an electrode assembly located inside the housing, wherein the housing is formed by a cylindrical body 2 with one end open and the aforementioned upper cover assembly 1.

[0040] The casing of the single battery cell 3 provided in this embodiment is made of plastic. The selected plastic material should have the following properties: First, it must have sufficient strength to ensure the stability of the battery structure; Second, it has chemical corrosion resistance and can resist the corrosion of electrolytes; Third, it has barrier properties, which can effectively prevent the electrolyte, gas and other substances inside the battery from leaking out, and at the same time prevent external impurities such as moisture and oxygen from entering the battery. Fourth, it possesses excellent thermal stability. Batteries generate heat during charging and discharging, especially at high rates. This plastic material needs to maintain stable performance within a certain temperature range and will not soften, deform, or decompose due to high temperatures.

[0041] The plastic material used can be the same material used in existing plastic-cased single-cell batteries 3, or the plastic material disclosed in Chinese patents CN106543551A and CN106977894A.

[0042] Since the upper cover plate 11 in this embodiment is made of plastic and uses injection molding, the stepped structure and the raised structure 14 can be precisely molded, ensuring the accuracy of the stepped structure and the raised structure 14. In addition, the injection molding process is low-cost and highly efficient, reducing processing steps and production costs, resulting in significant economic benefits in large-scale production.

[0043] In some other embodiments, a metal cover plate 11 and a cylinder 2 may also be used, and a stepped structure and a protruding structure 14 may be formed on the cover plate 11 by machining.

[0044] Preferably, in order to further reduce costs, the strength of the casing (including the cylinder 2 and the upper cover plate 11) of the single battery cell 3 meets certain requirements in this embodiment. In this embodiment, the casing strength is not required to meet the strength requirements during the thermal runaway stage; it only needs to meet the strength requirements during the formation stage and the normal charge / discharge process. During the formation stage and the normal charge / discharge process, the battery undergoes a series of chemical reactions and physical changes. During this process, certain pressure and heat are generated inside the battery. The casing needs to have sufficient strength to withstand this pressure and heat to ensure the smooth progress of the formation process and the normal use of the battery.

[0045] We can assume that the strength of the casing is P, P1≤P≤P2; where P1 is the strength requirement of the casing during the formation stage and the normal charging and discharging stage of the battery; and P2 is the strength requirement of the casing during the thermal runaway stage.

[0046] Under the premise of meeting the above strength requirements, in this embodiment, the thickness of the shell (cylinder 2 and upper cover plate 11) is h, where h is less than h0, and h0 is the thickness of the plastic shell of a conventional single-cell battery 3; the thickness of the plastic shell of a conventional single-cell battery 3 is typically 5-8 mm. In this embodiment, the thickness of the shell can be between 1-4 mm. By reducing the thickness of the shell of a conventional single-cell battery 3 with a plastic shell, better heat dissipation can be achieved, while also increasing the battery energy density. In addition, reducing the thickness of the plastic shell means using less plastic material, which helps save material costs and provides an economic advantage for large-scale production and application.

[0047] like Figure 4 The diagram shown is a partial structural schematic of the battery component in this embodiment. The housing of the battery component is not shown in the diagram. Each individual battery cell 3 is arranged in the housing along its thickness direction. Adhesive is injected into the housing. The height of the adhesive exceeds the horizontal plane of the stepped structure but is lower than the upper surface of the upper cover plate 11. After the adhesive cures, an adhesive layer is formed between each individual battery cell 3 and between the individual battery cell 3 and the housing.

[0048] This adhesive layer plays multiple key roles in the battery components: First, it has excellent structural bonding performance, which can firmly bond the dispersed individual cells 3 to the casing as a whole, improving the stability of the individual cells 3; Second, the adhesive layer material is made of thermally conductive adhesive with good thermal conductivity, which can quickly conduct the heat generated by the individual cells 3 during operation to the casing, and then dissipate heat to the outside through the casing, solving the problem of local heat accumulation caused by the dense arrangement of individual cells 3, and providing a suitable temperature environment for the long-term stable operation of the battery.

[0049] This embodiment can include a venting section on the casing, which can serve as the core pressure-bearing casing. This pressure-bearing casing must meet the compressive strength requirements during thermal runaway, meaning it must possess good strength. This design not only effectively resists the high-pressure impact during thermal runaway, greatly improving the overall safety of the battery component, but also, especially when using a relatively low-strength plastic casing as the inner cell 3 casing, forms a robust thermal barrier. Even in the extreme case of the cell 3 casing melting, it can effectively isolate high-temperature flames and harmful gases, preventing the spread of thermal runaway and improving the safety of the battery component after thermal runaway. Furthermore, when using plastic material as the inner cell 3 casing, an impermeable membrane can be provided between each cell 3 and the pressure-bearing casing to prevent the electrolyte inside each cell 3 from seeping outwards.

[0050] Compared to other materials, metal pressure tanks are more reliable in emergencies such as thermal runaway. They can withstand greater impact and destructive forces, reducing the likelihood of accidents and protecting the safety of personnel and surrounding equipment. In this embodiment, the pressure tank does not directly contact the electrolyte, so an iron, steel, or stainless steel shell can be used. Iron shells offer advantages in strength and cost, making them a viable option in scenarios where cost is a primary concern and strength requirements are not particularly stringent. Steel shells offer relatively high strength, providing more reliable protection for the battery and are suitable for applications with high safety and structural strength requirements. Stainless steel shells not only possess good strength properties but also excellent corrosion resistance, making them ideal for battery applications facing humid or corrosive environments. This effectively extends battery life and ensures stable operation in complex environments.

[0051] In the battery assembly, the polarity terminals 12 of each individual cell 3 may not extend out of the housing. Instead, the electrical connection between all individual cells 3 is completed inside the housing first, and then the total circuit is extended to the outside of the housing through a unified lead-out terminal or wiring structure.

[0052] Preferably, a clearance hole can be provided on the top of the housing corresponding to the position of the polarity terminal 12 of each individual battery 3; the polarity terminal 12 of each individual battery 3 extends out of the corresponding clearance hole, and the polarity terminal 12 and the clearance hole are insulated and sealed. Extending the polarity terminal 12 of the individual battery 3 out of the housing facilitates the electrical connection between individual batteries 3 and the electrical connection between the battery components and external equipment.

[0053] To optimize the heat dissipation performance of the aforementioned battery components, this embodiment can further add a heat exchange component to the battery components to exchange heat with the polarity terminal 12. The polarity terminal 12 is a key component connecting the battery's internal and external components; during charging and discharging, current flows through the polarity terminal 12 into and out of the battery. When heat is generated inside the battery, heat dissipation through the polarity terminal 12 provides a relatively direct heat conduction path. Heat can be quickly conducted from inside the battery to the polarity terminal 12, and then dissipated from the polarity terminal 12 to the external environment. Furthermore, since the polarity terminal 12 is typically located at the positive and negative terminals of the battery, and these areas are often where heat is concentrated during charging and discharging, heat dissipation through the polarity terminal 12 can more effectively reduce the temperature of these critical components. Example 2

[0054] like Figure 5 The diagram shown is a structural schematic of the single cell 3 in this embodiment. Unlike embodiment 1, this embodiment adds a connector to the cylindrical body 2 of the single cell 3. After the connectors of adjacent single cells 3 are connected to each other, the stability of each single cell 3 in the box can be further improved.

[0055] from Figure 5 and Figure 6 As can be seen from the diagram, the connector in this embodiment includes a first recess 21 and a first protrusion 22; the first recess 21 and the first protrusion 22 are respectively disposed on two opposite large surfaces of the cylinder 2 (for ease of description, the width direction of the cylinder 2 is defined as the y-direction, the thickness direction as the x-direction, and the height direction as the z-direction; here, the two large surfaces are two sidewalls parallel to the yz plane). Combined with... Figure 7 and Figure 8 In this embodiment, 12 individual cells 3 are arranged along the thickness direction of the individual cells 3. In each pair of adjacent individual cells 3, the first protrusion 22 of one individual cell 3 is embedded into the first recess 21 of the other individual cell 3 and fixedly connected.

[0056] As shown in the figure, in this embodiment, both the first recess 21 and the first boss 22 are rectangular structures with matching dimensions. They both extend along the height direction of the cylinder 2, and the bottom end of the first recess 21 is basically flush with the bottom end of the cylinder 2. A certain assembly gap can be reserved between the top end of the first recess 21 and the top end of the cylinder 2. Typically, this assembly gap is no more than 10mm, for example, a 1mm, 2mm, or 3mm assembly gap is reserved to facilitate the connection between the upper cover plate 11 and the open end of the top of the cylinder 2. In some other embodiments, the bottom end of the first recess 21 is flush with the bottom end of the cylinder 2, and the top end of the first recess 21 is also flush with the top end of the cylinder 2. That is, the height of the first recess 21 and the cylinder 2 are exactly the same, so that the first recess 21 has the maximum size in the height direction.

[0057] In other embodiments, the first recess 21 and the first protrusion 22 may also adopt other structural forms such as trapezoids. Compared with the trapezoidal structure, the rectangular structure of this embodiment is more compatible with the structure of the cylindrical body 2, making the overall structure of the cylindrical body 2 more regular. At the same time, after the two are connected, the force on the individual battery 3 is more even.

[0058] The first recess 21 can adopt the following two structural forms depending on the wall thickness of the cylinder 2: The first structure is suitable for scenarios where the wall thickness of cylinder 2 is relatively thick. A recessed area towards the inner cavity is directly excavated on the outer wall of cylinder 2.

[0059] The second structure is suitable for scenarios where the wall thickness of cylinder 2 is relatively thin. An annular protrusion can be set on the side wall of cylinder 2, and the area enclosed by the annular protrusion is the first recess 21. Figure 6As shown. If the wall thickness of the cylinder 2 is relatively thin, directly excavating the recess on the side wall will easily lead to further thinning of the wall thickness in the area corresponding to the first recess 21 and insufficient rigidity. However, this structure does not require excessive reduction of the side wall thickness, and the annular protrusion itself can enhance the structural strength of the recess area, providing a stable "slot foundation" for subsequent insertion with the first protrusion 22, and avoiding deformation of the first recess 21 during the insertion process.

[0060] like Figure 5 As shown, the first protrusion 22 is a rectangular protrusion that protrudes from the outer wall of the cylinder 2 away from the inner cavity of the cylinder 2. Its shape and size are adapted to the first recess 21, so that it can be embedded into the first recess 21 of another single battery 3 and tightly fitted with the first recess 21 to achieve a fixed connection.

[0061] Since the height of the first recess 21 and the first protrusion 22 in this embodiment is similar to that of the cylinder 2, and the overall size is relatively large, it is convenient for the two to quickly achieve coaxial alignment when they are inserted, thus completing the nested connection.

[0062] In some other embodiments, the connector can be a hollow tube disposed on the bottom plate of the cylinder 2 (the bottom plate of the cylinder 2 is parallel to the xy plane). The two ends of the hollow tube are closed, and through holes are formed in the hollow tube and the bottom plate of the cylinder 2. The hollow tubes of adjacent individual cells 3 are connected by inserting them into each other (after the connection is made, the closed ends can be opened by external force to make the inner cavities of each individual cell interconnected). However, compared with this embodiment, it has higher precision requirements for the hollow tube.

[0063] The first recess 21 and the first protrusion 22 are integrally formed with the cylinder 2, eliminating the problem of accumulated dimensional deviations caused by the assembly process. This ensures the stability and consistency of the connection between individual battery cells 3, which is beneficial to improving the overall performance and quality stability of the battery component and reducing problems such as poor connection and abnormal battery operation caused by dimensional mismatch. Simultaneously, in adjacent individual battery cells 3, after the first protrusion 22 of one individual battery cell 3 is embedded into the first recess 21 of another individual battery cell 3, the two can be fixedly connected by heat fusion. After the plastic cools and solidifies after heat fusion, the two become integrated, forming a stable connection structure capable of withstanding greater mechanical stress. For example, when the battery component is subjected to external forces such as vibration, impact, or compression, it effectively prevents the connection between the individual battery cells 3 from loosening or detaching, ensuring the structural integrity and electrical connection stability of the battery component under complex working conditions, thereby improving the safety and reliability of the battery component and extending its service life. Furthermore, the heat fusion connection method has lower precision requirements; even with a certain degree of dimensional deviation, a good connection can be achieved through heat fusion, reducing the precision control cost in the production process.

[0064] like Figure 5 and Figure 6As shown, in this embodiment, a second recess 23 and a second protrusion 24 can also be provided on the outer wall of the cylinder 2. The second recess 23 and the first recess 21 are symmetrical about the central axis of the cylinder 2, and the second protrusion 24 and the first protrusion 22 are symmetrical about the central axis of the cylinder 2. In the battery component, for every two adjacent individual cells 3, the first protrusion 22 and the second protrusion 24 of one individual cell 3 are respectively inserted into the first recess 21 and the second recess 23 of the other individual cell 3, and are fixedly connected by heat fusion. Compared with the battery component that connects individual cells 3 only through the first recess 21 and the first protrusion 22, the two sets of structures, the first recess 21 and the first protrusion 22, and the second recess 23 and the second protrusion 24, jointly fix adjacent individual cells 3 from different parts of the cylinder 2. This can more evenly distribute the compressive stress during the insertion connection, completely avoid the problem of stress concentration at a single connection point, significantly improve the firmness of the connection between individual cells 3, and further enhance the overall reliability of the battery component. Example 3

[0065] Based on the above embodiments, this embodiment may further include a second concave-convex structure 15 on the outer wall of the cylinder 2. Its structure may be the same as the first concave-convex structure 13, which is a stepped structure provided on the outer wall of the cylinder 2 and extending circumferentially therein. Alternatively, it may be as follows: Figure 5 The multiple groove structures shown extend along the height direction and are arranged along the width direction (this structure can also improve the overall strength of the cylinder 2). The adhesive is embedded in the grooves, which improves the mechanical interlocking force and connection stability between the adhesive layer and the cylinder 2, further enhancing the stability of the overall structure. In addition, the first and second concave-convex structures can make the connection between the top cover and the cylinder more reliable, reducing the probability of the connection between the top cover and the cylinder being torn when the battery cavity expands due to heat. Example 4

[0066] like Figure 9 and Figure 10 As shown, in this embodiment, based on embodiment 2 or embodiment 3, a first blind hole 25 and a second blind hole 26 corresponding to each other are provided on the first recess 21 and the first protrusion 22 respectively; under the action of external force, the bottom of the first blind hole 25 and the second blind hole 26 can be opened, thereby making the first blind hole 25 and the second blind hole 26 communicate with the inner cavity of the cylinder 2.

[0067] It should be noted that, in order to prevent damage to the structure of the first blind hole 25 and the second blind hole 26 when the first boss 22 and the first recess 21 are connected, the first boss 22 and the first recess 21 are only sealed and connected by heat fusion at the circumferential contact area.

[0068] from Figure 9 and Figure 10As can be seen, in this embodiment, there are four first blind holes 25 and four second blind holes 26, which are evenly arranged along the height direction of the cylinder 2. Specifically, the blind holes near the open end of the cylinder 2, when opened at the bottom, allow gas communication between the individual battery cells 3, balancing the internal gas pressure of each cell. The blind holes further away from the open end of the cylinder 2, when opened at the bottom, allow electrolyte communication between the individual battery cells 3, improving the consistency of each individual battery cell 3. In practical applications, the bottom of the corresponding blind holes can be opened according to actual needs.

[0069] In other embodiments, the number of the first blind hole 25 and the second blind hole 26 can be adjusted according to actual needs; alternatively, a single elongated blind hole can be used instead of multiple independent blind holes. However, compared to the multi-blind hole design in this embodiment, the elongated blind hole will result in a larger amount of material removal from the cylinder 2 in that area, weaker structural strength, and a greater susceptibility to deformation under stress.

[0070] In this embodiment, the "connection" and "internal cavity communication" functions of the single cell 3 are separated into two independent structures: the "connection" is handled by the first recess 21 and the first protrusion 22, and the "internal cavity communication" is handled by the first blind hole 25 and the second blind hole 26, thus avoiding the precision pressure caused by the superposition of functions.

[0071] From a connection perspective, the dimensions of the first recess 21 and the first boss 22 are much larger than those of the first blind hole 25 and the second blind hole 26. This large size design makes it easier and faster to achieve coaxial alignment when the two are inserted, facilitating nested connections and ensuring connection stability. From a communication perspective, since the connection is achieved independently by the structure of the first recess 21 and the first boss 22, the first blind hole 25 and the second blind hole 26 do not need to perform a positioning function. Even if there is a slight misalignment between the first blind hole 25 and the second blind hole 26 after connection, as long as their projection areas overlap to a certain extent, gas or electrolyte communication can still be achieved normally after opening the bottom. This significantly reduces the requirements for the machining accuracy of the first blind hole 25 and the second blind hole 26, effectively reducing production difficulty and cost.

[0072] In traditional designs, blind holes are often used as a composite structure that is both connected and interconnected. The blind hole needs to perform both positioning and connection functions at the same time. This requires that the blind holes of adjacent single cells 3 must be highly coaxial and precisely matched in size. Otherwise, problems such as "either misalignment or failure of connection" will occur. This results in extremely high requirements for the processing and assembly precision of blind holes, which not only increases the difficulty of the process but also increases the production cost.

[0073] like Figure 11 and Figure 12As shown, the housing contains 12 individual battery cells 3 as described in this embodiment. In each pair of adjacent individual battery cells 3, the first protrusion 22 of one individual battery cell 3 is inserted into the first recess 21 of the other individual battery cell 3, and the cells are sealed together by heat fusion at the circumferential contact point. The second protrusion 24 is inserted into the second recess 23 of the other individual battery cell 3, and the cells are fixed together by heat fusion.

[0074] After the first blind hole 25 and the corresponding second blind hole 26 are opened using tools, the inner cavities of each individual battery 3 are interconnected, and the first recess 21 and the first protrusion 22 of the first and last individual batteries 3 must remain sealed.

[0075] In the entire battery assembly, the internal cavities of all individual cells 3 are connected, which can effectively improve the differences that may exist between individual cells 3, ensure the consistency of each individual cell 3 during charging and discharging, extend the overall service life, and improve the performance of the battery assembly.

Claims

1. A top cover assembly for a single-cell battery, used to seal the open end of the top of the single-cell battery casing, comprising a top cover plate and polarity terminals fixed thereon; characterized in that: The side wall of the upper cover plate is provided with a first concave-convex structure for interlocking with the adhesive layer covering the side wall of the upper cover plate.

2. The top cover assembly for a single battery cell according to claim 1, characterized in that: The first concave-convex structure is a stepped structure, an annular protrusion, or an annular groove that extends circumferentially along the side wall of the upper cover plate.

3. The cover assembly for a single battery cell according to claim 1 or 2, characterized in that: The upper cover plate has a raised structure on its surface facing the inner cavity of the cylinder. When the upper cover assembly seals the open end of the top of the single battery cylinder, the raised structure presses against the top of the electrode assembly inside the cylinder.

4. A single-cell battery, characterized in that: The device includes a housing and an electrode assembly located within the housing cavity; the housing includes a cylindrical body with an open top and a top cover assembly sealed and fixed to the open top end of the cylindrical body; the top cover assembly is the top cover assembly for a single cell as described in any one of claims 1 to 3.

5. The single-cell battery according to claim 4, characterized in that: The cylindrical body is provided with a connector, which is used to connect with the connector of the adjacent individual battery cell.

6. The single-cell battery according to claim 4, characterized in that: The outer wall of the cylinder is provided with a second concave-convex structure, which is used to interlock with the adhesive layer covering the outer wall of the single battery cylinder.

7. The single-cell battery according to any one of claims 4 to 6, characterized in that: The casing is made of plastic and has a strength of P, where P1≤P≤P2; where P1 is the strength requirement of the casing during the formation stage and the normal charging and discharging stage of the battery; and P2 is the strength requirement of the casing during the thermal runaway stage.

8. A battery component, comprising a pressure-bearing housing and n individual batteries located within the pressure-bearing housing; wherein the individual batteries are the individual batteries as described in any one of claims 4 to 7, and n is an integer greater than 1; an adhesive layer is provided between each individual battery and between each individual battery and the pressure-bearing housing; the adhesive layer and a first concave-convex structure on the side wall of the upper cover plate are interlocked.

9. The battery component according to claim 8, characterized in that: The top plate of the pressure-bearing box has clearance holes corresponding to the polarity terminals of each individual battery; the area of ​​the top plate of the box corresponding to the clearance hole is fixedly sealed to the individual battery casing; the polarity terminals of each individual battery extend out of the clearance holes.

10. The battery component according to claim 9, characterized in that: The connectors of adjacent individual cells are connected to each other, and the inner cavities of adjacent individual cells are kept open through the connectors. The inner cavities of the first and last individual cells are kept sealed to the pressure tank.

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