Housing for single battery, single battery, and large capacity battery

Abstract

The application belongs to the field of batteries, and relates to a shell for a single battery, a single battery and a large-capacity battery. The shell for the single battery is made of plastic material. The single battery comprises the shell, and the large-capacity battery comprises a plurality of single batteries. A recess and a protrusion are arranged in a shell area corresponding to an electrode assembly support area. The recess is used for embedding and fixedly connecting the protrusion of another single battery. Under the action of external force, a channel can be formed in the protrusion and the recess, and the channel is in communication with an electrolyte area in a single battery shell cavity. A connecting piece is arranged on an upper cover plate, and is used for connecting a connecting piece on an adjacent single battery. Under the action of external force, a channel can be formed in the connecting piece, and the channel is in communication with a gas area in the single battery shell cavity. The shell for the single battery is made of plastic material, and has the advantages of low cost and light weight compared with finished batteries in the background art.

Description

Technical Field

[0001] This invention belongs to the field of batteries, specifically a casing for a single battery, a single battery cell, and a high-capacity battery. Background Technology

[0002] Chinese patent CN219658914U discloses a high-capacity battery, the structure of which is as follows: Figure 1 As shown, the battery includes a large-capacity battery body formed by several individual cells connected in parallel and a shared conduit located on the large-capacity battery. This shared conduit connects all the internal cavities of the individual cells, ensuring that all individual cells in the large-capacity battery are within a single system. This shared conduit enhances the uniformity of the individual cells within the large-capacity battery and improves cycle life.

[0003] The single battery in the aforementioned patent includes a housing, a sealing assembly, and a finished battery. The finished battery is installed inside the housing, and the finished battery housing has an opening. The housing has a first through hole communicating with the opening, and a pipe 01 extending along the width or length direction of the housing. The side wall of the pipe has a second through hole communicating with the first through hole. The sealing assembly is disposed on the opening, the first through hole, or the second through hole.

[0004] By setting a first through hole and a pipe with a second through hole on the outer casing of a single cell, a shared pipeline 02 can be formed through the pipe when assembling a large-capacity battery; moreover, by adding an outer casing to the finished battery, existing finished battery production lines can be used to put the finished battery into production with slight modifications.

[0005] However, this design has some drawbacks. Typically, both the finished battery casing and the outer shell are made of aluminum, which makes the overall cost of large-capacity batteries higher and their weight heavier.

[0006] From a cost perspective, aluminum is a relatively expensive metal. Furthermore, the manufacturing process for aluminum casings is complex, requiring multiple steps such as cutting, stamping, and welding, and demanding advanced equipment and techniques. These factors combined inevitably lead to a significant increase in the manufacturing cost of large-capacity batteries.

[0007] From a weight perspective, the stacking of two aluminum components significantly increases the overall weight of a large-capacity battery. This is extremely disadvantageous for the use, storage, and transportation of large-capacity batteries. Summary of the Invention

[0008] The purpose of this invention is to provide a casing for a single battery, a single battery cell, and a high-capacity battery, overcoming the technical difficulties of high cost and heavy weight of existing high-capacity batteries.

[0009] The concept of this invention is:

[0010] This invention addresses the aforementioned technical challenges primarily by focusing on both the structure of the individual battery cell itself and its packaging structure.

[0011] Firstly, starting from the structure of the individual battery itself, reduce the cost and weight of large-capacity batteries;

[0012] Given that plastic materials have a lower density than aluminum materials and are relatively cheaper, this invention aims to replace the finished batteries in the prior art with finished batteries using plastic casings (finished batteries can also be called single-cell batteries).

[0013] Compared to traditional aluminum casings, plastic casings are significantly lighter. Furthermore, plastic materials are less expensive, and the manufacturing process is relatively simple, requiring no complex equipment or technology. This effectively reduces manufacturing costs, increases production efficiency, and provides a cost advantage in large-scale production.

[0014] Secondly, starting from the packaging structure of individual cells, we can reduce the weight and cost of large-capacity batteries.

[0015] This invention proposes placing multiple individual battery cells with plastic casings within a single pressure-bearing casing, which can simultaneously protect multiple individual cells. Compared to the prior art structure where each individual cell is individually encased in a casing, this reduces individual packaging and protection costs, resulting in lower overall cost. Furthermore, given the same number of individual cells, the weight of a single pressure-bearing casing is necessarily less than the weight of multiple smaller casings; therefore, the design of the pressure-bearing casing can further reduce the weight of large-capacity batteries.

[0016] Based on the above inventive concept, the first aspect of the present invention provides a housing for a single battery, which is characterized in that it is formed by an upper cover plate, a cylindrical body and a lower cover plate; wherein the upper cover plate, the cylindrical body and the lower cover plate are all made of plastic.

[0017] Along the height of the housing, from bottom to top, the inner cavity of the housing is divided into an electrode assembly support area and an electrode assembly receiving area;

[0018] A first recess and a first protrusion are provided in the housing area corresponding to the electrode assembly support area; wherein the first recess is used for the first protrusion on the housing of another single cell to be embedded and fixedly connected; under the action of external force, a channel can be opened in the first recess and the first protrusion, and the channel communicates with the electrolyte area inside the single cell housing.

[0019] The top cover is equipped with a connector for connecting to the connector on the adjacent single cell. Under external force, a channel can be opened in the connector, which communicates with the gas area inside the single cell casing.

[0020] After the individual battery cells are connected via the first recess, the first protrusion, and the connector, this invention utilizes a tool to create channels in the first recess and the first protrusion that penetrate the electrolyte region within the individual battery cell casing. This allows the electrolyte in each individual battery cell to be interconnected, ensuring they are all within the same electrolyte system. Furthermore, channels are created within the connector that penetrate the gas region within the individual battery cell casing, enabling gas communication and achieving gas balance between the individual cells. This addresses potential differences between individual battery cells in terms of both electrolyte and gas, ensuring consistency during charging and discharging, extending the overall lifespan, and improving the performance of the large-capacity battery. Additionally, connecting the individual battery cells at different locations effectively enhances the stability of the individual cells within the casing, making the entire large-capacity battery structure more robust and durable.

[0021] The casing for the single-cell battery provided by the present invention is made of plastic, which has the advantages of low cost and light weight compared with the finished batteries used in the prior art.

[0022] Meanwhile, by making full use of the electrode assembly support area inside the casing, the first recess and the first protrusion are set in this area. The first recess and the first protrusion do not affect the size of the single cell in the height direction. In the large-capacity battery, both the connection stability and the overall compactness and space utilization efficiency of the large-capacity battery are ensured.

[0023] Furthermore, the connector is a second recess and a second protrusion disposed on opposite sidewalls of the upper cover plate; wherein the second recess is used for the second protrusion of another single battery cell to be embedded and fixedly connected, and under the action of external force, a channel can be opened in the second recess and the second protrusion, which communicates with the gas area inside the cavity of the single battery cell.

[0024] This invention fully utilizes the structure of the top cover plate itself, placing the second recess and the second protrusion on opposite sidewalls of the top cover plate. The second recess and the second protrusion do not affect the dimensions of the individual cells in the height direction, thus balancing the overall compactness and space utilization efficiency of the large-capacity battery. Furthermore, when assembling the large-capacity battery, the second protrusion of one individual cell is inserted into the second recess of another individual cell and fixedly connected, which improves the stability between the individual cells and makes the entire large-capacity battery structure more robust and durable.

[0025] Furthermore, the second recess is a second blind hole opened on the first side wall of the upper cover plate; the second protrusion is a second pair of connecting pipes provided on the outer wall of the second side wall of the upper cover plate; the second pair of connecting pipes are used to insert into the second blind hole of another single cell and to fix them in place; the first side wall of the upper cover plate and the second side wall of the upper cover plate are parallel to each other.

[0026] This invention employs a second blind hole and a second pair of connecting pipes, making the connection process simple and convenient. It allows for quick and accurate connection of individual battery cells, making the assembly of the entire large-capacity battery more orderly and efficient. Furthermore, once inserted and secured, they form a mortise and tenon joint-like connection, ensuring a reliable connection between adjacent battery cells. This prevents loosening or displacement of individual cells when subjected to vibration or impact, thus guaranteeing the stability of the large-capacity battery's performance and its lifespan.

[0027] In addition, the placement of the second blind hole and the second connector does not affect the sealing performance of the individual battery casing.

[0028] Furthermore, a channel communicating with the inner cavity of the second connecting pipe is provided on the upper cover plate; a partition is provided in the channel, and a cavity is formed between the partition and the bottom end of the second blind hole. A through hole is provided in the upper cover plate area corresponding to the cavity for communicating with the inner cavity of the single cell.

[0029] Under the action of external force, the separator and the bottom of the second blind hole can be opened, so that the inner cavity of the second connector, the inner cavity of the channel, and the inner cavity of the second blind hole are all connected to the inner cavity of the single cell.

[0030] By creating a channel in the upper cover plate that communicates with the inner cavity of the second pair of connectors, it is easy to connect the inner cavity of the second pair of connectors and the inner cavity of the individual battery through external force in the later stage. At the same time, the inner cavity of this channel is connected to the inner cavity of the individual battery through a through hole in the upper cover plate. In order to ensure that the internal environment of the individual battery is not affected by the external environment, a partition is required to isolate the through hole from the inner cavity of the second pair of connectors. In the later stage, when it is necessary to connect the inner cavities of each individual battery, the partition and the bottom end of the second blind hole are opened under the action of external force, so that the inner cavities of the second pair of connectors, the inner cavity of the channel, and the inner cavity of the second blind hole are all connected to the inner cavity of the individual battery.

[0031] Furthermore, the aforementioned connector can also be a sub-pipe segment disposed on the upper surface of the upper cover plate; the sub-pipe segment is a hollow pipe fitting; the hollow pipe fitting and the upper cover plate have interconnected openings, and both ends of the hollow pipe fitting are closed ends.

[0032] Define the two closed ends as the first closed end and the second closed end, respectively;

[0033] A third blind hole extending axially is provided at the first closed end; the third blind hole is used for the insertion and fixed connection of the second closed end of another single cell hollow tube.

[0034] Under the action of external force, the first and second closed ends of the hollow tube can be opened.

[0035] The sub-pipe section of this invention adopts a hollow pipe structure, with both ends made as closed ends. At the same time, on the upper cover plate, openings are precisely made at positions corresponding to the sub-pipe section, communicating with each other.

[0036] On the one hand, when multiple individual cells are assembled, adjacent individual cells can be stably connected with the help of sub-tubes, which greatly improves the stability of the individual cells in the box, and thus makes the structure of the entire large-capacity battery exhibit better stability and durability.

[0037] On the other hand, although the two ends of this sub-tube segment are normally closed, they can be opened smoothly under specific external forces. Once the closed ends are opened, the inner cavities of all sub-tube segments are immediately connected, and further connected with the inner cavities of all individual cells. In this way, the differences that may exist between individual cells can be effectively improved, ensuring the consistency of each individual cell during charging and discharging, extending the overall service life, and improving the performance of large-capacity batteries.

[0038] Furthermore, the first recess is a first blind hole formed on the first side wall of the lower cover plate; the first protrusion is a first pair of connecting pipes provided on the outer wall of the second side wall of the lower cover plate; the first pair of connecting pipes are used to be embedded in the first blind hole of another single cell and fixedly connected, and the first side wall of the lower cover plate and the second side wall of the lower cover plate are parallel to each other.

[0039] This invention employs a first blind hole and a first connecting pipe for connection, making the connection process simple and convenient. It allows for quick and accurate connection of individual cells, making the assembly process of the entire large-capacity battery more orderly and efficient. Once they are interlocked and fixed, a reliable connection is formed between adjacent cells, ensuring that the cells will not easily loosen or shift when subjected to vibration or impact, thus maintaining a stable electrical connection and structural state for a long time.

[0040] In addition, the placement of the first blind hole and the first connecting pipe does not affect the sealing performance of the individual battery casing.

[0041] Furthermore, the inner surface of the lower cover plate is provided with multiple protrusions arranged in an array. The top of the protrusions is used to support the electrode assembly, and the gap between the protrusions serves as an electrolyte flow channel.

[0042] The regularly arranged protrusions provide stable and evenly distributed support points for the electrode assembly, preventing deformation or damage caused by excessive localized stress. Furthermore, the gaps between the protrusions serve as electrolyte flow channels, allowing the electrolyte to be evenly distributed around the electrode assembly, ensuring that all electrodes are in full contact with the electrolyte.

[0043] Furthermore, under the action of external force, the bottom end of the first blind hole and the second side wall area of ​​the lower cover plate defined by the first connecting pipe can be opened and connected to the electrolyte flow channel.

[0044] The first blind hole and the first connecting pipe of the present invention are both hollow structures. On the one hand, when multiple individual cells are assembled, adjacent individual cells can be stably connected by means of the first blind hole and the first connecting pipe, which greatly improves the stability of the individual cells in the box, and thus makes the structure of the entire large-capacity battery exhibit better stability.

[0045] On the other hand, although the inner cavities of the first blind hole and the first connecting pipe are normally isolated from the battery cavity, under specific external force, the bottom end of the first blind hole and the area of ​​the second side wall of the lower cover plate enclosed by the first connecting pipe can be opened smoothly. Once the closed end is opened, the inner cavities of all the first blind holes and the first connecting pipe are immediately connected to the electrolyte flow channel, and further connected to the inner cavities of all individual cells. In this way, the differences that may exist between individual cells can be effectively improved, ensuring the consistency of each individual cell during charging and discharging, extending the overall service life, and improving the performance of the large-capacity battery.

[0046] Furthermore, a weak section is integrally provided on the top cover plate; the strength of the weak section is less than the strength of the rest of the top cover plate, and when a single cell experiences thermal runaway, the thermal runaway smoke breaks through the weak section and is discharged.

[0047] The weak part of the present invention is integrally set with the upper cover plate, which has at least the following advantages:

[0048] From a structural stability perspective, existing explosion-proof membranes are typically attached to the battery cover plate via adhesive or other methods. During long-term use, factors such as corrosion from internal battery chemicals, temperature changes, and mechanical vibrations can cause the connection between the explosion-proof membrane and the cover plate to loosen or detach, leading to a failure of its explosion-proof function. In contrast, the integrated weak point in this invention is a single unit with the cover plate, eliminating the risk of loosening or detachment at the connection point. This significantly improves structural stability and reliability, ensuring consistently excellent explosion-proof performance.

[0049] In terms of sealing, achieving an absolute seal at the junction of the existing explosion-proof membrane and the top cover faces numerous challenges. However, the seamless integration of the integrated weak point with the top cover effectively ensures the internal sealing of the battery under normal conditions, preventing the intrusion of external substances and providing a better environment for stable battery operation.

[0050] From a cost and manufacturing process perspective, existing explosion-proof membranes require additional materials and complex installation processes, which not only increases production costs but may also lead to inconsistent product quality due to human factors during manufacturing. In contrast, the integrated design of the weak point eliminates the need for additional installation steps during manufacturing, simplifying the production process, reducing production costs, and improving product consistency and quality stability.

[0051] A recessed area can be created on the top cover to form a weak point. Compared to methods that create weak points by altering material composition or microstructure, creating a recessed area is simpler and allows for more intuitive and precise control over the strength and opening pressure of the weak point. Specifically, by controlling parameters such as the depth, shape, and area of ​​the recessed area, the opening of the weak point under a specific pressure can be accurately set, greatly improving the reliability of the explosion venting function.

[0052] Alternatively, through holes can be made along the width or length of the top cover to form a weak point. When through holes are made along the width or length of the top cover to form a weak point, the flatness of the battery top cover can be maintained better than a weak point formed by a recessed area.

[0053] The aforementioned weak point is located between the two polarity terminals of the top cover. This allows for timely dissipation of heat generated by thermal runaway, effectively mitigating localized high temperatures. Furthermore, compared to placing the weak point in other locations, it reduces interference with other functional areas of the battery, achieving a more efficient layout within a limited space.

[0054] Furthermore, both the first recess and the first protrusion are integral with the housing; the first recess is used for the first protrusion of another single battery cell to be inserted and is fixedly connected by heat fusion.

[0055] The connector and the top cover are integrated; the connector is used to fix and connect with the connector of another single battery cell by heat fusion.

[0056] This invention can be manufactured using injection molding, where the first recess and the first protrusion are integrally formed on the lower cover plate or cylinder, and the connector is integrally formed on the upper cover plate. The manufacturing process is simple. Since the first recess, the first protrusion, the connector, and the shell are formed simultaneously, there is no problem of dimensional deviation caused by subsequent assembly. The precision is high, which can ensure that the first recess, the first protrusion, and the connector of each individual battery can be precisely matched, which is beneficial to the mass production and quality control of large-capacity batteries.

[0057] Furthermore, the first recess, the first protrusion, and adjacent connectors are connected via a heat-fusion method. During the heat-fusion process, the plastic material melts upon heating, and upon cooling and solidification, the materials fuse together to form a single, integrated structure. This creates a very strong bond between the recess and protrusion, and between adjacent connectors. This connection method can withstand significant tensile, compressive, and shear forces, effectively preventing loosening or separation of individual cells during use and ensuring the structural stability of large-capacity batteries. Simultaneously, heat-fusion connection has lower precision requirements; even with dimensional deviations between the recess and corresponding protrusions and connectors during production, precise connection can still be achieved, greatly improving production efficiency.

[0058] A second aspect of the present invention provides a single-cell battery, characterized in that it includes the aforementioned casing for a single-cell battery.

[0059] Furthermore, the shell strength is P, P1≤P≤P2; where P1 is the strength requirement of the shell during the formation stage and the normal charging and discharging stage of the battery; and P2 is the strength requirement of the shell during the thermal runaway stage.

[0060] The aforementioned single-cell battery casing is a sealed plastic casing that serves as a cavity for the electrode components and electrolyte, providing a sealing function. Simultaneously, the strength of the sealed casing must meet the strength requirements of the casing during the formation stage and the normal charge / discharge stages of the battery. That is, the sealed casing must possess sufficient strength to ensure that it will not crack under changes in the internal environment of the battery, such as temperature and pressure, during the formation stage and normal charge / discharge stages. Compared to existing finished plastic-cased single-cell batteries, this single-cell battery has a lower cost, thereby reducing the overall cost of the large-capacity battery.

[0061] A third aspect of the present invention provides a high-capacity battery, characterized in that it includes a pressure-bearing housing and n of the above-mentioned single cells arranged within the pressure-bearing housing, wherein n is an integer greater than 1;

[0062] In adjacent single cells, the first protrusion of one single cell is embedded into the first recess of another single cell and fixedly connected. The first protrusion and the first recess form a channel that penetrates the electrolyte area inside the cell housing. The connector of one single cell is fixedly connected to the connector of another single cell, and the connector has a channel that penetrates the gas area inside the cell housing.

[0063] The pressure-bearing shell has the strength required for the shell during the thermal runaway stage, and the pressure-bearing shell is equipped with a venting section.

[0064] The outer casing of the high-capacity battery of this invention is a pressure-bearing shell, whose strength must meet the requirements for shell strength during thermal runaway; that is, the pressure-bearing shell must have good strength to protect multiple individual cells simultaneously. In the extreme case of thermal runaway of a single cell and melting of the plastic shell, the pressure-bearing shell can form a robust barrier, effectively isolating high-temperature flames and harmful gases, preventing the spread of thermal runaway, and improving the safety of the high-capacity battery after thermal runaway. Compared with the structure of individual cell casings in the prior art, this reduces the cost of individual packaging and protection, resulting in lower costs. Furthermore, given the same number of individual cells and the same material and thickness of the pressure-bearing shell as the individual cell casings in the prior art, the weight of a single pressure-bearing shell is necessarily less than the weight of multiple smaller casings. Therefore, the design of the pressure-bearing shell can further reduce the weight of the high-capacity battery.

[0065] Furthermore, when each individual cell has a weak point, a venting channel is formed between the weak point of each individual cell and the pressure-bearing casing.

[0066] The pressure-bearing casing is equipped with a venting section corresponding to the venting channel. In the event of thermal runaway of a single cell, the runaway gas ruptures through the weak point, passes through the venting channel, and then ruptures the venting section before exiting the pressure-bearing casing. In the initial stage of thermal runaway, the runaway gas can be discharged in an orderly manner through the venting channel, effectively preventing its spread to the large-capacity battery casing and thus preventing further deterioration of the thermal runaway situation.

[0067] Furthermore, the top plate of the pressure-bearing housing has clearance holes corresponding to the polarity terminals of each individual battery; the polarity terminals of each individual battery extend out of the clearance holes; the area of ​​the top plate of the pressure-bearing housing corresponding to the clearance holes is fixedly sealed to the individual battery housing.

[0068] Furthermore, the aforementioned high-capacity battery also includes a heat exchange component that exchanges heat with the polarity terminals.

[0069] During the operation of a large-capacity battery, heat can easily accumulate at the polarity terminals due to current conduction. Heat exchange components can promptly remove this heat, ensuring the polarity terminals remain within a suitable operating temperature range. This not only helps maintain the performance stability of individual cells within the large-capacity battery and reduces performance degradation caused by excessive temperature, but also further enhances the overall safety and reliability of the large-capacity battery, preventing potential malfunctions caused by localized overheating.

[0070] The beneficial effects of this invention are:

[0071] The single-cell battery of this invention uses a plastic casing, which enables the large-capacity battery constructed from it to have lower cost and lighter weight.

[0072] Meanwhile, to improve the safety performance of the high-capacity battery constructed from the aforementioned individual cells, this invention places multiple individual cells within a pressure-bearing casing. In extreme cases where a single cell experiences thermal runaway and the plastic casing melts, this pressure-bearing casing forms a robust thermal barrier, effectively isolating high-temperature flames and harmful gases, and preventing the spread of thermal runaway. Furthermore, protecting multiple individual cells with a pressure-bearing casing reduces external impacts and damage during transportation and use, extending battery life. Compared to the prior art structure where each individual cell is individually encased, this reduces individual packaging and protection costs, resulting in lower overall cost. Moreover, with the same number of individual cells, the weight of a single pressure-bearing casing is necessarily less than the weight of multiple smaller casings; therefore, the design of the pressure-bearing casing further reduces the weight of the high-capacity battery.

[0073] Meanwhile, the present invention makes full use of the electrode assembly support area inside the shell, and sets the first recess and the first protrusion in this area. The first recess and the first protrusion do not affect the size of the single cell in the height direction, thus taking into account the overall compactness and space utilization efficiency of the large-capacity battery.

[0074] Furthermore, improvements are made to address potential differences between individual battery cells in terms of both electrolyte and gas, ensuring consistency in charge and discharge processes, extending overall lifespan, and enhancing the performance of the large-capacity battery. Additionally, connecting individual batteries at different locations effectively strengthens their stability within the casing, resulting in a more robust and durable overall structure for the large-capacity battery. Attached Figure Description

[0075] Figure 1 This is a schematic diagram of the structure of a large-capacity battery in the background art;

[0076] Figure 2 This is a schematic diagram of the structure of a single cell in Example 1 from a first-view perspective;

[0077] Figure 3 This is a schematic diagram of the structure of a single cell in Example 1 from a second perspective;

[0078] Figure 4 This is a schematic diagram of a partial structure of the single battery casing in Example 1;

[0079] Figure 5 This is a partial cross-sectional view of the single battery casing in Example 1;

[0080] Figure 6 This is a partial structural cross-sectional view of the single-cell battery casing in some other embodiments;

[0081] Figure 7 This is a schematic diagram of the structure of the top cover of a single battery cell in Example 1 from a first-view perspective;

[0082] Figure 8 This is a schematic diagram of the structure of the top cover plate of a single battery cell in Example 1 from a second perspective;

[0083] Figure 9 This is a cross-sectional view of the top cover of a single battery cell in Example 1;

[0084] Figure 10 This is a schematic diagram of the structure of the top cover of a single battery cell in Example 2 from a first-view perspective;

[0085] Figure 11 This is a schematic diagram of the structure of the top cover plate of the single cell in Example 2 from a second perspective;

[0086] Figure 12 This is a structural schematic diagram of the top cover plate of a single battery cell in Example 2 from a third-view perspective;

[0087] Figure 13 This is a schematic diagram of the structure of a single cell in Example 2;

[0088] Figure 14 This is a schematic diagram of the structure of a single-cell battery cover plate in Example 4;

[0089] Figure 15 This is a schematic diagram of the structure of another single-cell battery cover plate in Example 4;

[0090] Figure 16 This is a schematic diagram of the structure of a single-cell battery cover assembly in Example 5;

[0091] Figure 17 This is a schematic diagram of the structure of a single cell in Example 5;

[0092] Figure 18 This is a schematic diagram of the structure of another single-cell battery cover plate from a first-view perspective in Example 5;

[0093] Figure 19 This is a schematic diagram of the structure of the top cover plate of another single cell in Example 5 from a second perspective;

[0094] Figure 20 This is a schematic diagram of another single-cell battery in Example 5;

[0095] Figure 21 This is a schematic diagram of the structure of the large-capacity battery in Example 6;

[0096] Figure 22 This is a schematic diagram of the exploded structure of a high-capacity battery in Example 6;

[0097] Figure 23 This is a schematic diagram of a partial explosion structure of a large-capacity battery in Example 6;

[0098] Figure 24 This is a schematic diagram of the partial explosion structure of the second type of large-capacity battery in Example 6;

[0099] Figure 25 This is a schematic diagram of the partial explosion structure of the third type of large-capacity battery in Example 6;

[0100] Figure 26 This is a schematic diagram of the partial explosion structure of the fourth type of large-capacity battery in Example 6;

[0101] Figure 27 This is a schematic diagram of the partial explosion structure of the fifth type of high-capacity battery in Example 6;

[0102] Figure 28 This is a schematic diagram of the exploded structure of the sixth type of high-capacity battery in Example 6;

[0103] Figure 29 This is a schematic diagram of the sixth type of high-capacity battery in Example 6.

[0104] The attached figures are labeled as follows:

[0105] 01. Pipeline; 02. Shared pipeline;

[0106] 1. Top cover plate; 11. Polar terminal; 2. Cylinder; 3. Bottom cover plate; 31. First blind hole; 32. Bottom of the first blind hole; 33. First connecting pipe; 4. Electrode assembly support area; 5. Electrode assembly receiving area; 6. First recess; 7. First protrusion; 10. Sub-pipe section; 12. Boss; 13. Pressure-bearing shell; 14. Heat exchange component; 15. Single cell; 16. Explosion vent; 17. Clearance hole; 18. Third blind hole; 19. Opening; 21. Second recess; 23. Second protrusion; 24. First side wall of top cover plate; 25. Second side wall of top cover plate; 26. Second blind hole; 261. Stepped surface of countersunk hole; 262. Bottom of the second blind hole; 27. Second connecting pipe; 28. Channel; 29. ​​Through hole; 210. Partition plate; 42. Through groove; 45. Groove; 46. Through hole. Detailed Implementation

[0107] 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.

[0108] 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.

[0109] 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," "third," "fourth," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0110] Example 1

[0111] like Figure 2 and Figure 3The diagram shown is a structural schematic of a single battery cell 15 in this embodiment. The single battery cell 15 includes a housing, an electrode assembly located in the inner cavity of the housing, and an electrolyte. The housing is formed by an upper cover plate 1, a cylindrical body 2, and a lower cover plate 3.

[0112] To reduce costs and battery weight, this embodiment uses a plastic casing. The lower cover plate 3 and the cylinder 2 can be molded in one piece using injection molding, eliminating the need for separate processing and assembly. This significantly reduces production steps and shortens the production cycle. Furthermore, the injection-molded integral part ensures uniform material distribution and tight bonding, resulting in a stronger connection between the battery lower cover plate 3 and the cylinder 2, and higher overall structural strength. Additionally, reinforcing ribs can be integrally molded on the cylinder 2, effectively increasing its resistance to bending, compression, and torsion.

[0113] In this embodiment, the upper cover plate 1 and the cylinder 2 can be sealed together by heat fusion or welding. This ensures a continuous, uniform, and tight connection between the upper cover plate 1 and the cylinder 2, resulting in extremely high stability. External water, dust, and other impurities cannot enter the battery, thus providing excellent protection for the electrode components and ensuring the battery's performance and lifespan.

[0114] It should be noted that the plastic material selected in this invention should have the following properties:

[0115] First, it must have sufficient strength to ensure the stability of the battery structure;

[0116] Second, it has chemical corrosion resistance and can resist the corrosion of electrolytes;

[0117] 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.

[0118] 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.

[0119] The plastic material used can be the same material used in existing plastic-cased single-cell batteries 15, or the plastic material disclosed in Chinese patents CN106543551A and CN106977894A.

[0120] For ease of description, in this embodiment, the width direction of the casing of the single battery 15 is defined as the x-direction, the length direction as the y-direction, and the height direction as the z-direction.

[0121] In this embodiment, along the z-direction from bottom to top, the inner cavity of the housing is divided into an electrode assembly support area 4 and an electrode assembly receiving area 5.

[0122] Combination Figure 4 and Figure 5 As can be seen, in this embodiment, the electrode assembly support area 4 is mainly located on the lower cover plate 3; the electrode assembly receiving area 5 is located above the electrode assembly support area 4.

[0123] In some other embodiments, such as Figure 6 As shown, the electrode assembly support area 4 can be enclosed by the lower cover plate 3 and a portion of the cylinder 2 connected thereto; the electrode assembly receiving area 5 is located above the electrode assembly support area 4.

[0124] The present invention provides a first recess 6 and a first protrusion 7 on the housing area corresponding to the electrode assembly support area 4; wherein the first recess 6 is used for embedding and fixing the first protrusion 7 on the housing of another single battery 15. Under the action of external force, a channel can be formed in the first recess 6 and the first protrusion 7, and the channel communicates with the electrolyte area inside the housing of the single battery 15.

[0125] The first recess 6 and the first protrusion 7 of the present invention are interlocked to connect multiple individual battery cells 15, which can also improve the stability of the individual battery cells 15 in the large-capacity battery, making the structure of the entire large-capacity battery more compact and stable, effectively resisting interference under various working conditions, and ensuring the continuous, efficient and safe operation of the large-capacity battery.

[0126] This invention places both the first recess 6 and the first protrusion 7 on the housing corresponding to the electrode assembly support area 4, ensuring that the first recess 6 and the first protrusion 7 do not generate additional dimensional increments in the height direction of the individual battery cell 15. For high-capacity batteries, especially in applications with stringent space requirements, this connection structure that does not increase height dimensions is particularly important. It allows a large-capacity battery to accommodate more individual batteries 15 within a limited space, or, while meeting the same battery capacity requirements, makes the overall large-capacity battery more compact and lightweight, facilitating device portability, installation, and layout optimization.

[0127] Since the shell in this embodiment is made of plastic, it can be integrally molded using injection molding, forming a shell with the first recess 6 and the first protrusion 7 (the shell here consists of a lower cover plate 3 and a cylindrical body 2). During injection molding, the dimensions of the mold cavity can be precisely controlled, ensuring high dimensional accuracy of the first recess 6 and the first protrusion 7 during molding, guaranteeing precise fit with other individual battery cells 15. Furthermore, because it is integrally molded, there is no issue of accumulated dimensional deviations due to the assembly process, ensuring the stability and consistency of the individual battery cell connections. This is beneficial for improving the overall performance and quality stability of the large-capacity battery, reducing problems such as poor connection and abnormal battery operation caused by dimensional mismatch. Simultaneously, in adjacent individual battery cells 15, after the first protrusion 7 of one individual battery cell 15 is embedded into the first recess 6 of another individual battery cell 15, the two can be fixedly connected by heat fusion. After the plastic is melted and cooled, it solidifies, fusing the two together to form a stable connection structure capable of withstanding significant mechanical stress. For example, when a large-capacity battery is subjected to external forces such as vibration, impact, or compression, it effectively prevents the connections between individual cells from loosening or detaching. This ensures the structural integrity and electrical connection stability of the large-capacity battery under complex operating conditions, thereby improving its safety and reliability and extending its lifespan. Furthermore, the hot-melt connection method has lower precision requirements; even with a certain degree of dimensional deviation, a good connection can be achieved through hot melting, reducing the cost of precision control during the production process.

[0128] from Figure 2 and Figure 3 As can be seen from the image, in this embodiment, the first recess 6 and the first protrusion 7 are respectively disposed on the first sidewall and the second sidewall, which are parallel to each other on the housing. In addition, two first recesses 6 may be provided on the first sidewall, and two corresponding first protrusions 7 may be provided on the second sidewall.

[0129] In some other embodiments, a first recess 6 and a first protrusion 7 may be provided on the first sidewall, and a first protrusion 7 and a first recess 6 may be provided on the second sidewall.

[0130] In this embodiment, when assembling a large-capacity battery, the operator can easily distinguish the correspondence between the first recess 6 and the first protrusion 7, and can quickly and accurately connect each individual battery cell 15. However, if there are both first recesses 6 and first protrusions 7 on the same side wall, the operator needs to be more careful in distinguishing which first recess 6 corresponds to which first protrusion 7 during assembly. If not careful, mismatch may occur, resulting in reduced assembly efficiency.

[0131] It should be noted that:

[0132] 1. The first sidewall mentioned above is composed of the first sidewall of the cylinder 2 and the first sidewall of the lower cover plate; the second sidewall mentioned above is composed of the second sidewall of the cylinder 2 and the second sidewall of the lower cover plate.

[0133] 2. The first and second sidewalls described above are parallel to each other and can both be parallel to the xz plane. When parallel to the xz plane, both the first protrusion 7 and the first recess 6 extend along the y direction. Alternatively, both the first and second sidewalls described above can be parallel to the yz plane. When parallel to the yz plane, both the first protrusion 7 and the first recess 6 extend along the x direction.

[0134] The following example mainly focuses on the first and second sidewalls being parallel to the yz plane.

[0135] from Figure 5 As can be seen, in this embodiment, the first recess 6 is a first blind hole 31 opened on the first side wall of the lower cover plate, that is, the opening end of the first blind hole 31 is located on the first side wall of the lower cover plate, and the bottom end 32 of the first blind hole is located in the electrode assembly support area 4. The first protrusion 7 is a first pair of connecting tubes 33 provided on the outer wall of the second side wall of the lower cover plate; the first pair of connecting tubes 33 is used to be embedded in the first blind hole 31 of another single cell 15 and fixedly connected.

[0136] In some other embodiments, the first recess 6 may also be employed Figure 6 The structure shown, namely the first recess 6, can be a sub-tube segment 10 disposed on the first side wall of the cylinder 2; the sub-tube segment 10 extends along the x-direction, with one end closed and the other end open; the closed end is located within the electrode assembly support area 4, and the open end penetrates through the first side wall of the cylinder and is located on the first side wall of the cylinder. The first protrusion 7 is a first pair of connecting pipes 33 disposed on the outer wall of the second side wall of the cylinder 2; the first pair of connecting pipes 33 is used to embed into the first blind hole 31 of another single cell 15 and to fix it in place.

[0137] In some other embodiments, the first protrusion 7 can also be a solid column, which has higher strength and can withstand greater tensile and compressive forces. However, compared to this embodiment, it is more difficult to create a through-hole channel in it that penetrates the inner cavity of the shell.

[0138] from Figure 4 and Figure 5 It can also be seen that this embodiment has multiple protrusions 12 arranged in an array on the inner surface of the lower cover plate 3. The tops of the protrusions 12 are used to support the electrode assembly, and the gaps between the protrusions 12 serve as electrolyte flow channels. The aforementioned multiple protrusions 12 can be arranged in a rectangular array or a ring array, etc.; the regularly arranged multiple protrusions 12 can provide stable and uniformly distributed support points for the electrode assembly, avoiding the situation where excessive local stress leads to deformation or damage of the electrode assembly. In addition, using the gaps between the protrusions 12 as electrolyte flow channels allows the electrolyte to be evenly distributed around the electrode assembly, ensuring that the electrodes in each part can fully contact the electrolyte.

[0139] Furthermore, during battery operation, if the temperature rises, the electrolyte stored in the electrolyte flow channel 28 can quickly absorb heat through heat transfer, dispersing the absorbed heat throughout the casing and dissipating it through the casing surface. This effectively prevents battery overheating, reduces the risk of thermal runaway, precisely regulates temperature, and maintains battery performance.

[0140] In addition, in this embodiment, both the first blind hole 31 and the first connecting pipe 33 are hollow structures. After being constructed into a high-capacity battery, under the action of external force, the area of ​​the second side wall of the lower cover plate enclosed by the bottom end 32 of the first blind hole and the first connecting pipe 33 will be hollow. Figure 5 The area shown in the middle circle (a) can be opened, immediately connecting the inner cavities of all the first blind holes 31 and the first connecting pipe 33, and further connecting them with the electrolyte areas of all individual battery cells 15, achieving electrolyte sharing. In this way, the differences that may have existed between individual battery cells 15 can be effectively improved, ensuring the consistency of each individual battery cell 15 during charging and discharging, extending the overall service life, and improving battery performance.

[0141] If adopted Figure 6 The structure shown, after being constructed into a high-capacity battery, under the action of external force, the closed end of the sub-tube segment 10 and the second side wall area of ​​the lower cover plate enclosed by the first pair of tubes 33 ( Figure 6 The area shown in the middle circle (a) can be opened, immediately connecting the inner cavities of all sub-tube segments 10 and the first pair of tubes 33, and further connecting them with the inner cavities of all individual cells 15. This can also improve the differences that may exist between individual cells 15, ensure the consistency of each individual cell 15 during charging and discharging, extend the overall service life, and improve the performance of the battery.

[0142] The above-mentioned external force generally refers to using appropriate tools to apply a certain force to the second side wall area of ​​the lower cover plate enclosed by the bottom end 32 of the first blind hole (or the closed end of the sub-pipe section 10) and the first connecting pipe 33, causing it to break and form an opening.

[0143] like Figure 7 and Figure 8 The diagram shown is a structural schematic of the upper cover plate 1 of the single cell 15 in this embodiment.

[0144] In this embodiment, a second recess 21 and a second protrusion 23 are provided on opposite sidewalls of the upper cover plate 1 as connecting members. When assembling a large-capacity battery, the second protrusion 23 of one single cell 15 can be inserted into the second recess 21 of another single cell 15 and fixedly connected. Under the action of external force, a channel can be opened in the second recess 21 and the second protrusion 23, and the channel communicates with the gas area inside the housing of the single cell 15.

[0145] In addition, the second recess 21 and the second protrusion 23 cooperate with the first protrusion 7 and the first recess 6 to connect adjacent single cells 15 from different positions, improve the stability of the single cell 15 in the large-capacity battery, make the structure of the entire large-capacity battery more compact and stable, effectively resist interference under various working conditions, and ensure the continuous, efficient and safe operation of the large-capacity battery.

[0146] In this embodiment, the second recess 21 and the second protrusion 23 are both located on opposite sidewalls of the upper cover plate 1, ensuring that the second recess 21 and the second protrusion 23 do not generate additional dimensional increases in the height direction of the individual battery cell 15. For large-capacity batteries, especially in applications with stringent space requirements, this connection structure that does not increase height dimensions is particularly important. It allows a large-capacity battery to accommodate more individual battery cells 15 within a limited space, or, while meeting the same battery capacity requirements, makes the overall large-capacity battery more compact and lightweight, facilitating device portability, installation, and layout optimization.

[0147] This embodiment employs injection molding to integrally form the upper cover plate 1 with the second recess 21 and the second protrusion 23. During injection molding, the dimensions of the mold cavity can be precisely controlled, ensuring high dimensional accuracy of the second recess 21 and the second protrusion 23 during molding, guaranteeing precise fit with other individual battery cells 15. Furthermore, since it is integrally molded, there is no issue of accumulated dimensional deviations due to the assembly process, ensuring the stability and consistency of the individual battery cell connections. This is beneficial for improving the overall performance and quality stability of the large-capacity battery, reducing problems such as poor connection and abnormal battery operation caused by dimensional mismatch. Simultaneously, in adjacent individual battery cells 15, after the second protrusion 23 of one individual battery cell 15 is inserted into the second recess 21 of another individual battery cell 15, 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 significant mechanical stress. For example, when the large-capacity battery is subjected to external forces such as vibration, impact, or compression, it effectively prevents the connection between the individual battery cells 15 from loosening or detaching, ensuring the structural integrity and electrical connection stability of the large-capacity battery under complex operating conditions, thereby improving the safety and reliability of the large-capacity battery and extending its service life. In addition, the hot-melt connection method has lower precision requirements. Even with a certain degree of dimensional deviation, a good connection can be achieved through hot-melt, which reduces the precision control cost in the production process.

[0148] from Figure 7 and Figure 8 As can be seen from the image, in this embodiment, the second recess 21 and the second protrusion 23 are respectively provided on the first sidewall and the second sidewall of the upper cover plate 1, which are parallel to each other. In addition, two second recesses 21 can be provided on the first sidewall 24 of the upper cover plate, and two second protrusions 23 are correspondingly provided on the second sidewall 25 of the upper cover plate.

[0149] In some other embodiments, a second recess 21 and a second protrusion 23 may be provided on the first sidewall 24 of the upper cover plate, and a second protrusion 23 and a second recess 21 may be provided on the second sidewall 25 of the upper cover plate.

[0150] In this embodiment, when assembling a large-capacity battery, the operator can easily distinguish the correspondence between the second recess 21 and the second protrusion 23, and can quickly and accurately connect each individual battery cell 15. However, if there are both second recesses 21 and second protrusions 23 on the same side wall, the operator needs to be more careful in distinguishing which second recess 21 corresponds to which second protrusion 23 during assembly. If not careful, mismatch may occur, resulting in reduced assembly efficiency.

[0151] It should be noted that the first sidewall 24 and the second sidewall 25 of the upper cover plate are parallel to each other and can both be parallel to the xz plane. When parallel to the xz plane, the second protrusion 23 and the second recess 21 both extend along the y direction. Alternatively, the first sidewall 24 and the second sidewall 25 of the upper cover plate can both be parallel to the yz plane. When parallel to the yz plane, the second protrusion 23 and the second recess 21 both extend along the x direction.

[0152] The following example mainly illustrates that the first side wall 24 and the second side wall 25 of the upper cover plate are parallel to the yz plane.

[0153] like Figure 9 As shown, in this embodiment, the second recess 21 is a second blind hole 26 formed on the first sidewall 24 of the upper cover plate, that is, the opening end of the second blind hole 26 is located on the first sidewall 24 of the upper cover plate. The inner cavity of the second blind hole 26 is used to accommodate the second protrusion 23 of another single cell 15, and is fixedly connected to the second protrusion 23 by means of heat fusion.

[0154] In some other embodiments, the second recess 21 may also be a groove 45 formed on the first sidewall 24 of the upper cover plate, or a similar structure.

[0155] from Figure 9 As can be seen from the diagram, the second blind hole 26 in this embodiment adopts a countersunk hole structure. The stepped surface 261 of the countersunk hole is used to mate with the end face of the second protrusion 23. When the second protrusion 23 is inserted into the second blind hole 26, the stepped surface and the end face of the second protrusion 23 are tightly fitted, limiting the second protrusion 23 in the axial direction. This effectively prevents unnecessary displacement of the second protrusion 23 in the axial direction, thereby avoiding problems such as loose connection and poor contact caused by displacement, and ensuring that the individual cells 15 maintain a stable connection state during long-term use of the large-capacity battery.

[0156] The second protrusion 23 is a second pair of connecting pipes 27 disposed on the second side wall 25 of the upper cover plate; the second pair of connecting pipes 27 is used to insert into the second blind hole 26 of another single cell 15 and is fixedly connected by heat fusion. The second pair of connecting pipes 27 adopts a hollow structure, which effectively reduces the overall weight while ensuring the connection function.

[0157] In some other embodiments, the second protrusion 23 can also be a solid column. A solid column has higher strength than the hollow structure of the second connecting pipe 27 and can withstand greater tensile and compressive forces. However, compared to this embodiment, it is more difficult to create a through channel in it that communicates with the inner cavity of the single battery cell 15 casing.

[0158] In this embodiment, there can be two second blind holes 26. Each second blind hole 26 extends along the x-direction, and the two second blind holes 26 are arranged along the y-direction and are located on the outside of the two polarity terminals 11, respectively. Correspondingly, there are also two second pairs of connectors 27, which correspond one-to-one with the two second blind holes 26. Each second pair of connectors 27 extends along the x-direction, and the two second pairs of connectors 27 are arranged along the y-direction and are located on the outside of the two polarity terminals 11, respectively.

[0159] From a stress perspective, the above arrangement ensures that when adjacent individual cells 15 are connected, and the large-capacity battery is subjected to complex external forces from different directions, the forces can be distributed relatively evenly to the corresponding parts of the battery through the two second connecting pipes 27 and the second blind hole 26, thus avoiding excessive local stress that could damage the connection structure or cause displacement of the individual cells 15.

[0160] Furthermore, in this embodiment, both the second blind hole 26 and the second connecting pipe 27 are hollow structures. After being constructed into a high-capacity battery, under external force, the inner cavities of the second blind hole 26 and the second connecting pipe 27 can be interconnected. By opening through holes 29 at the corresponding positions on the cover plate 1 along the interconnected path, all the inner cavities of the second blind holes 26 and the second connecting pipe 27 are immediately interconnected, and further interconnected with the gas regions of all individual battery cells 15, achieving gas balance (for ease of description, in this embodiment, a high-capacity battery in which the gas regions of all individual battery cells 15 are interconnected is defined as a high-capacity battery). In this way, the differences that may originally exist between individual battery cells 15 can be effectively improved, ensuring the consistency of each individual battery cell 15 during charging and discharging, extending the overall service life, and improving the performance of the high-capacity battery.

[0161] Specifically, to facilitate the connection between the inner cavity of the second blind hole 26 and the inner cavity of the second connecting pipe 27, such as Figure 9As shown, in this embodiment, a channel 28 communicating with the inner cavity of the second connecting pipe 27 is provided on the upper cover plate 1. The channel 28 is isolated from the inner cavity of the second blind hole 26 through the bottom end 262 of the second blind hole. At the same time, a through hole 29 communicating with the inner cavity of the channel 28 is provided on the upper cover plate 1, and a partition 210 is also required to be provided in the channel 28 to isolate the inner cavity of the single battery 15 from the external environment.

[0162] The aforementioned partition 210 and the bottom end 262 of the second blind hole have at least the following functions:

[0163] First, the function of preventing external substances from entering the interior of the single cell 15 before or during the construction of a large-capacity battery.

[0164] The separator 210 and the bottom of the second blind hole 262 play crucial roles in the use of the single cell 15. Before and during the construction of a large-capacity battery, the single cell 15 is in an independent state. If the internal environment of the battery is affected by external factors, its performance will be impaired. For example, if air from the external environment enters the battery through the second connector 27, channel 28, through hole 29 or the bottom of the second blind hole 262 and through hole 29, it may trigger an oxidation reaction, affecting the chemical reaction balance inside the battery; the entry of moisture may cause problems such as short circuits or electrode corrosion; the intrusion of other impurities will also damage the electrochemical system inside the battery.

[0165] This embodiment is specially designed with a partition 210 and a second blind hole 26 to create a robust barrier, ensuring that air, water and other impurities in the external environment cannot enter the individual battery 15 through the through hole 29 via the second connector 27 and the opening of the second blind hole 26.

[0166] To achieve this function, certain requirements are placed on the strength of the separator 210. It needs to have a certain structural strength and sealing performance to resist various external pressures and corrosion, thereby creating a stable and clean environment inside the individual battery 15 and ensuring that the battery performance is not adversely affected by external factors.

[0167] Secondly, the partition 210 and the bottom end 262 of the second blind hole can be opened by a package opening tool to achieve the function of gas communication;

[0168] After the large-capacity battery is assembled, a special unpacking tool is needed to open the separator 210 and the bottom of the second blind hole 262, thereby connecting the gas regions inside all the individual cells 15 and completing the assembly of the large-capacity battery.

[0169] To meet this functional requirement, the separator 210 and the bottom of the second blind hole 262 must be able to be opened by an unpacking tool. This requires that the separator 210 and the bottom of the second blind hole 262 be designed to be able to be opened smoothly by an unpacking tool, and that the opening process will not damage other parts of the high-capacity battery, ensuring that the integrity and functionality of the high-capacity battery are not affected.

[0170] In addition, such as Figure 2 , Figure 3 , Figure 7 and Figure 8 As shown, in this embodiment, a through groove 42 can also be formed on the upper surface of the upper cover plate 1, and the area of ​​the upper cover plate 1 corresponding to the bottom of the through groove 42 is regarded as a weak part. When thermal runaway occurs inside the single cell 15 and the internal pressure reaches a certain requirement, the thermal runaway flue gas breaks through the weak part to form an opening and is discharged from the opening of the weak part.

[0171] In some other embodiments, an annular groove may be formed on the upper cover plate 1, and the area enclosed by the annular groove may be used as a weak part.

[0172] from Figure 7 As can be seen from the image, in this embodiment, the through groove 42 penetrates the upper cover plate 1 along the x direction and is located between the two polarity terminals 11 of the upper cover plate 1.

[0173] From a thermal management perspective, the polar terminals 11 are usually the concentrated areas of heat generation in the battery. By placing the weak points near the two polar terminals 11, the heat generated by thermal runaway can be dissipated in a timely manner, effectively alleviating local high temperatures and optimizing the internal heat distribution of the battery.

[0174] In terms of structural layout, this arrangement makes the battery top cover 1 more compact and rational. Compared to placing the weakest part in other locations, it reduces interference with other functional areas of the battery, achieving a more efficient layout within a limited space.

[0175] In some other embodiments, the through slot 42 can also extend through the upper cover plate 1 along the length of the upper cover plate 1, avoiding the location of the polarity terminal 11.

[0176] The depth and width of the through groove 42 can be set according to specific needs to ensure that the area of ​​the upper cover plate 1 where the bottom of the through groove 42 is located can be opened under the set pressure.

[0177] However, it is important to note that the depth and width of the through-slot 42 should not be excessive. If the dimensions exceed a reasonable range, the through-slot 42 may deform due to insufficient strength when the battery has not experienced thermal runaway, thereby affecting battery performance. Therefore, during the design phase, it is necessary to comprehensively consider the various stresses that the top cover 1 will bear during normal battery operation, including internal pressure and external vibration. By rationally planning the corresponding dimensions of the through-slot 42, while ensuring the structural stability of the top cover 1 under normal operating conditions, it is also ensured that the through-slot 42 can reliably perform its explosion-venting function in the event of thermal runaway.

[0178] In this embodiment, the top cover 1 is made of plastic and can be integrally molded using injection molding to form a top cover 1 with a second recess, a second protrusion, and a through groove 42. The low density of the plastic material significantly reduces the overall weight of the battery. Simultaneously, thanks to the good plasticity of the plastic, the injection molding process allows for precise control of the mold cavity dimensions, ensuring high dimensional accuracy of the second recess and second protrusion during molding, guaranteeing precise fit with other individual battery cells 15. Furthermore, because it is integrally molded, there is no issue of accumulated dimensional deviations due to the assembly process, ensuring the stability and consistency of the individual battery cell connections. This is beneficial for improving the overall performance and quality stability of the large-capacity battery, reducing problems such as poor connection and abnormal battery operation caused by dimensional mismatch. Additionally, in adjacent individual battery cells 15, after the second protrusion of one individual battery cell 15 is inserted into the second recess of another individual battery cell 15, the two can be fixedly connected by heat fusion. After the plastic is melted and cooled, it solidifies, fusing the two together to form a stable connection structure capable of withstanding significant mechanical stress. For example, when a large-capacity battery is subjected to external forces such as vibration, impact, or compression, it effectively prevents the connections between individual cells from loosening or detaching. This ensures the structural integrity and electrical connection stability of the large-capacity battery under complex operating conditions, thereby improving its safety and reliability and extending its lifespan. Furthermore, the hot-melt connection method has lower precision requirements; even with a certain degree of dimensional deviation, a good connection can be achieved through hot melting, reducing the cost of precision control during the production process.

[0179] The one-piece molded through-slot 42 also avoids additional splicing gaps, ensuring the overall sealing of the top cover 1 and effectively preventing the intrusion of external impurities. 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.

[0180] Example 2

[0181] Unlike Example 1, as Figure 10 , Figure 11 and Figure 12As shown, in this embodiment, a sub-tube segment 10 is provided on the upper surface of the upper cover plate 1 as a connector. The inner cavity of the sub-tube segment is used to communicate with the inner cavity of the individual battery cell 15. By connecting the corresponding sub-tube segments of multiple individual batteries 15, a shared pipeline can be formed. In addition, connecting the sub-tube segments of multiple individual batteries 15 can also improve the stability of the individual battery cell 15 in the large-capacity battery, making the structure of the entire large-capacity battery more compact and stable, effectively resisting interference under various operating conditions, and ensuring the continuous, efficient, and safe operation of the large-capacity battery. In this embodiment, the sub-tube segment is set on a weak part. In some other embodiments, the sub-tube segment can be set in other positions on the upper cover plate.

[0182] The aforementioned sub-tube section 10 preferably adopts a hollow tube, whose internal hollow structure is beneficial to reducing the overall weight and can also serve as a shared channel; furthermore, it can seal both ends of the hollow tube, and at the same time, it has through holes 19 on the hollow tube and the upper cover plate 1, so that the inner cavity of the hollow tube can serve as a gas storage cavity, and the gas generated inside the battery can be stored in this space to prevent bulging.

[0183] Furthermore, when a high-capacity battery is constructed using individual cells 15 with this sub-tube structure, the two closed ends of the hollow tube can be opened under external force, instantly connecting the inner cavities of all sub-tubes and further connecting them with the gas regions within the inner cavities of all individual cells 15, achieving gas balance within each individual cell 15. This effectively mitigates potential differences between individual cells 15, ensuring consistency during charging and discharging, extending overall lifespan, and improving the performance of the high-capacity battery.

[0184] The above-mentioned external force generally refers to using appropriate tools to apply a certain force to the closed end, causing it to break and form an opening.

[0185] from Figures 10 to 12 As can be seen from the figure, the sub-pipe section 10 in this embodiment adopts a hollow pipe fitting. The hollow pipe fitting and the lower cover plate 3 have interconnected openings 19, and both ends of the hollow pipe fitting are closed ends (in this embodiment, the two sides of the hollow pipe fitting located at the openings 19 in the axial direction of the hollow pipe fitting are referred to as the two ends of the hollow pipe fitting); for ease of description, in this embodiment, the closed ends of the two ends of the hollow pipe fitting are defined as the first closed end and the second closed end, respectively.

[0186] This can be achieved in several ways. One feasible method is to set a sealing gasket or sealing plug inside or at the end of the hollow tube, thereby effectively blocking the channels at both ends of the hollow tube and forming a closed end. Alternatively, a sealing plate can be integrally formed inside the hollow tube, which can also achieve the purpose of sealing both ends of the hollow tube.

[0187] To facilitate the connection of adjacent hollow pipes, this embodiment uses a circular reducing pipe. The outer diameter of the first closed end of the reducing pipe is larger than the outer diameter of the second closed end. A third blind hole 18 extending axially is opened at the first closed end, and an upper cover plate 1 extends from the second closed end.

[0188] In a pair of adjacent hollow tubes, the second closed end of one hollow tube is inserted into the third blind hole 18 of the other hollow tube and fixed by heat fusion, thus connecting the two hollow tubes. The length of the second closed end extending out of the upper cover plate 1 and the depth of the third blind hole 18 can be adjusted to ensure that the two individual cells 15 are close together after connection.

[0189] Preferably, in this embodiment, the third blind hole 18 adopts a countersunk hole structure. The stepped surface 261 of the countersunk hole is used to mate with the end face of the second closed end of the hollow tube. When the second closed end of the hollow tube is inserted into the third blind hole 18, the stepped surface and the end face of the second closed end are tightly fitted, limiting the hollow tube in the axial direction. This effectively prevents unnecessary displacement of the hollow tube in the axial direction, thereby avoiding problems such as loose connection and poor contact caused by displacement, and ensuring that the individual cells 15 maintain a stable connection state during long-term use of the large-capacity battery.

[0190] When using the sub-tube segment with this structure, on the one hand, when multiple individual cells 15 are assembled, adjacent individual cells 15 can be stably connected with the help of the sub-tube segment, which greatly improves the stability of the individual cells 15 in the box, thereby making the structure of the entire large-capacity battery exhibit better stability and durability.

[0191] On the other hand, although the two ends of the sub-tube segment 10 are normally closed, under the specific action of external force, its two closed ends can be opened smoothly. Once the closed ends are opened, the inner cavities of all sub-tube segments are immediately connected, and further connected with the gas regions inside the inner cavities of all individual cells 15.

[0192] Similar to Embodiment 1, the top cover 1 in this embodiment is also made of plastic and can be integrally molded using injection molding to form the top cover 1 with the sub-tube segment 10 and the through groove 42. The low density of the plastic material significantly reduces the overall weight of the battery. Simultaneously, thanks to the good plasticity of the plastic, the injection molding process allows for precise control of the mold cavity dimensions, ensuring high dimensional accuracy of the sub-tube segment 10 during molding and guaranteeing precise fit with other individual battery cells 15. Furthermore, since it is integrally molded, there is no issue of accumulated dimensional deviations due to the assembly process, ensuring the stability and consistency of the connection between the individual battery cells 15. This is beneficial for improving the overall performance and quality stability of the large-capacity battery and reducing problems such as poor connection and abnormal battery operation caused by dimensional mismatch. Additionally, in adjacent individual battery cells 15, after the sub-tube segment 10 of one individual battery cell 15 is inserted into the third blind hole 18 of the sub-tube segment of another individual battery cell 15, the two can be fixedly connected by heat fusion. After the plastic is melted and cooled, it solidifies, fusing the two together to form a stable connection structure capable of withstanding significant mechanical stress. For example, when a large-capacity battery is subjected to external forces such as vibration, impact, or compression, it effectively prevents the connections between individual cells from loosening or detaching. This ensures the structural integrity and electrical connection stability of the large-capacity battery under complex operating conditions, thereby improving its safety and reliability and extending its lifespan. Furthermore, the hot-melt connection method has lower precision requirements; even with a certain degree of dimensional deviation, a good connection can be achieved through hot melting, reducing the cost of precision control during the production process.

[0193] The one-piece molded through-slot 42 also avoids additional splicing gaps, ensuring the overall sealing of the top cover 1 and effectively preventing the intrusion of external impurities. 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.

[0194] like Figure 13 As shown, the single battery 15 with the upper cover assembly of this embodiment includes a housing, which is formed by the cylindrical body 2, the lower cover plate 3, and the aforementioned upper cover plate 1. Except for the upper cover plate 1, which differs from that of Embodiment 1, the rest of the structure is the same as that of Embodiment 1, and will not be described again here.

[0195] Example 3

[0196] Unlike the embodiments described above, this embodiment, in order to further reduce costs, requires that the strength of each individual battery cell 15 casing meets certain requirements. 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. (Correspondingly, the strength of the weak points provided on it should also meet the strength requirements during the formation stage and the normal charge / discharge process.) During the formation stage and the normal charge / discharge stage, 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.

[0197] 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.

[0198] Under the premise of meeting the above strength requirements, in this embodiment, the thickness of the shell (cylinder 2, upper cover plate 1, and lower cover plate 3) is h, where h is less than h0, and h0 is the thickness of the plastic shell of a conventional single-cell battery 15; the thickness of the plastic shell of a conventional single-cell battery 15 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 15 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.

[0199] Example 4

[0200] Unlike the above embodiments, this embodiment has a groove 45 formed on the lower surface of the upper cover plate 1, and the area of ​​the upper cover plate 1 corresponding to the bottom of the groove 45 is a weak part.

[0201] Specifically, such as Figure 14 and Figure 15 As shown, Figure 14 Taking the connector from Embodiment 1 as an example, Figure 15 Taking the connector from Embodiment 2 as an example.

[0202] In this embodiment, the groove 45 extends along the x-direction, similar to embodiment 1, and the groove 45 is located between the two polar terminals 11.

[0203] The depth and width of the groove 45 can be set according to specific needs to ensure that the area of ​​the upper cover plate 1 where the bottom of the groove 45 is located can be opened under the set pressure.

[0204] However, it is also important to note that the depth and width of the groove 45 should not be too large. If the dimensions exceed a reasonable range, the groove 45 may deform due to insufficient strength when the battery has not experienced thermal runaway, thereby affecting battery performance. Therefore, during the design phase, it is necessary to comprehensively consider the various stresses that the top cover 1 will bear during normal battery operation, including internal pressure and external vibration. By rationally planning the corresponding dimensions of the groove 45, while ensuring the structural stability of the top cover 1 under normal operating conditions, it is also necessary to ensure that the groove 45 can reliably perform its explosion-proof function in the event of thermal runaway.

[0205] Compared to the example of opening a through groove 42 on the upper surface of the upper cover plate 1 in Example 1, this example can better maintain the flatness of the battery upper cover plate 1.

[0206] In addition, during normal operation of the single cell 15, the inner cavity of the groove 45 can serve as a gas storage cavity, where the gas generated inside the single cell 15 can be stored, thus reducing the degree of bulging of the single cell 15 casing.

[0207] Example 5

[0208] Unlike the above embodiments, this embodiment has a through hole 46 in the upper cover plate 1 along its width direction, forming a weak part.

[0209] Specifically, such as Figures 16 to 20 As shown, Figure 16 and Figure 17 Taking the connector from Embodiment 1 as an example, Figures 18 to 20 Taking the connector in Embodiment 2 as an example, the sub-pipe segment 10 is located inside the through hole 46.

[0210] This embodiment also uses a plastic cover plate 1, which can be integrally molded using injection molding process to form a cover plate 1 with a through hole 46.

[0211] As can be seen from the figure, in this embodiment, the through hole 46 extends through the upper cover plate 1 along the width direction of the upper cover plate 1 and is located between the two polarity terminals 11 of the upper cover plate 1.

[0212] In some other embodiments, a through hole 46 along the length of the upper cover plate 1 may be formed to create a weak point.

[0213] The cross-sectional shape and size of the through hole 46 can be set according to specific requirements to ensure that the area of ​​the upper cover plate 1 where the bottom of the through hole 46 is located can be opened under the set pressure.

[0214] However, it is also important to note that the through hole 46 should not be too large. If it exceeds a reasonable range, the through hole 46 may deform due to insufficient strength when the battery has not experienced thermal runaway, thus affecting battery performance. Therefore, during the design phase, it is necessary to comprehensively consider the various stresses that the top cover 1 will bear during normal battery operation, including internal pressure and external vibration. By rationally planning the corresponding dimensions of the through hole 46, while ensuring the structural stability of the top cover 1 under normal operating conditions, it is also necessary to ensure that the through hole 46 can reliably perform its explosion-venting function in the event of thermal runaway.

[0215] Compared to the weak point in Embodiment 1, this embodiment can also better maintain the flatness of the battery cover plate 1.

[0216] Example 6

[0217] This embodiment is a high-capacity battery, including a pressure-bearing housing 13 and 12 individual battery cells 15 arranged within the pressure-bearing housing 13 as described in the above embodiment. In other embodiments, the number of individual battery cells 15 can be adjusted according to actual needs.

[0218] Its structure is as follows Figures 21 to 27 As shown, Figure 22 and Figure 23 China and Israel adopt Figure 13 Taking the single cell 15 shown as an example, in adjacent single cells 15, the first connecting pipe 33 of one single cell 15 is embedded into the first blind hole 31 of the other single cell 15 and connected by heat fusion. One end of the sub-tube segment 10 of one single cell 15 is inserted into the third blind hole 18 on the sub-tube segment 10 of the other single cell 15 and connected by heat fusion.

[0219] Figure 24 To adopt Figure 2 Taking the single cell 15 shown as an example, in adjacent single cells, the first pair of connecting pipes 33 of one single cell 15 is embedded into the first blind hole 31 of another single cell 15 and connected by heat fusion. The second pair of connecting pipes 27 of one single cell 15 is inserted into the second blind hole 26 of another single cell 15 and connected by heat fusion.

[0220] Figure 25 To adopt Figure 14 Taking the single cell 15 corresponding to the top cover plate as an example, in adjacent single cells, the first pair of connecting pipes 33 of one single cell 15 is embedded into the first blind hole 31 of another single cell 15 and connected by heat fusion. The second pair of connecting pipes 27 of one single cell 15 is inserted into the second blind hole 26 of another single cell 15 and connected by heat fusion.

[0221] Figure 26 China and Israel adopt Figure 20Taking the single cell 15 shown as an example, in adjacent single cells 15, the first connecting pipe 33 of one single cell 15 is embedded into the first blind hole 31 of the other single cell 15 and connected by heat fusion. One end of the sub-tube segment 10 of one single cell 15 is inserted into the third blind hole 18 on the sub-tube segment 10 of the other single cell 15 and connected by heat fusion.

[0222] Figure 27 To adopt Figure 17 Taking the single cell 15 shown as an example, in adjacent single cells, the first pair of connecting pipes 33 of one single cell 15 is embedded into the first blind hole 31 of another single cell 15 and connected by heat fusion. The second pair of connecting pipes 27 of one single cell 15 is inserted into the second blind hole 26 of another single cell 15 and connected by heat fusion.

[0223] In this embodiment, appropriate tools are used to open the second sidewall area of ​​the lower cover plate defined by the bottom end 32 of the first blind hole and the first connecting pipe 33 of each individual battery cell 15, so that the inner cavities of all the first blind holes 31 and the inner cavities of the first connecting pipe 33 are connected, and further connected to the inner cavities of all the individual battery cells 15, so that the electrolyte in the inner cavities of all the individual battery cells 15 is shared, thereby obtaining a large-capacity battery. Based on the sharing of electrolyte, the differences that may originally exist between individual battery cells 15 are improved, ensuring the consistency of each individual battery cell 15 during the charging and discharging process, extending the overall service life, and improving the performance of the large-capacity battery.

[0224] The aforementioned tool should have a sharp head and a certain strength, such as a long steel needle. Specifically, the following process can be used to open the second sidewall area of ​​the lower cover plate enclosed by the bottom end 32 of the first blind hole of each individual battery 15 and the first connecting pipe 33: Along the x-direction, insert the tool into the first blind hole 31 of one of the outermost individual batteries 15, apply a pushing force, and open the second sidewall area of ​​the lower cover plate enclosed by the bottom end 32 of the first blind hole of each individual battery 15 and the first connecting pipe 33.

[0225] It should be noted that:

[0226] 1. To ensure that the inner cavity of each individual cell 15 in the large-capacity battery is not affected by the external environment, the second side wall area of ​​the lower cover plate enclosed by the first connecting pipe 33 of one of the two outermost individual cells 15 of the large-capacity battery does not need to be opened, and the opening of the first blind hole 31 of the other outermost individual cell 15 also needs to be sealed.

[0227] 2. In order to improve the regularity of the entire large-capacity battery structure, in this embodiment, the outermost single cell 15 can be cut off to expose the first pair of connecting pipes 33 that do not need to be connected. After cutting off, it is necessary to ensure the sealing of the casing of the single cell 15.

[0228] In this embodiment, the aforementioned tool is used to open the bottom 262 of the second blind hole of each individual battery cell 15 and the separator 210 (or the closed end of the sub-tube segment 10), so that the inner cavity of all the second blind holes 26 and the inner cavity of the second connecting pipe 27 are connected (or the inner cavity of all the sub-tube segments 10 are connected), and further connected with the gas region inside the cavity of all individual batteries 15, so that the gas inside the cavity of all individual batteries 15 is balanced, thereby obtaining a large-capacity battery. Based on the gas connection, the differences that may originally exist between individual batteries 15 are improved, ensuring the consistency of each individual battery 15 during the charging and discharging process, extending the overall service life, and improving the performance of the large-capacity battery.

[0229] against Figure 24 , Figure 25 and Figure 27 Specifically, the structure shown can be opened by the following process: insert a tool into the second blind hole 262 of one of the outermost single cells 15 along the x-direction and apply a pushing force to open the second blind hole bottom 262 and the separator 210 of each single cell 15.

[0230] It should be noted that:

[0231] 1. To ensure that the inner cavity of each individual cell 15 in the large-capacity battery is not affected by the external environment, one of the two outermost individual cells 15 of the large-capacity battery does not need to be opened, and the opening of the second blind hole 26 of the other outermost individual cell 15 also needs to be sealed.

[0232] 2. In order to improve the regularity of the entire large-capacity battery structure, in this embodiment, the outermost single cell 15 can be cut off to expose the second pair of connecting pipes 27 that do not need to be connected. After cutting off, it is necessary to ensure the sealing of the casing of the single cell 15.

[0233] against Figure 23 and Figure 26 The structure shown can be opened by the following process: insert a tool into the third blind hole of one of the outermost individual cells 15 along the x-direction and apply a pushing force to open the closed end of the sub-tube segment of each individual cell 15.

[0234] It should be noted that:

[0235] To ensure that the internal cavity of each individual cell 15 in the large-capacity battery is not affected by the external environment, the closed end of one of the two outermost individual cells 15 does not need to be opened, and the opening of the third blind hole 18 of the other outermost individual cell 15 also needs to be sealed.

[0236] When each individual cell 15 has a weak point at the top, a venting channel is formed between the weak point of each individual cell 15 and the pressure-bearing casing 13.

[0237] Figure 23 and Figure 24 In the middle, the weak part is the through groove 42. The through grooves 42 of each individual battery 15 are connected (or spliced) to form an explosion relief channel. This explosion relief channel is located between the weak part of each individual battery 15 and the pressure-bearing housing 13. Alternatively, a channel can be provided on the pressure-bearing housing 13. This channel covers the through grooves 42 of each individual battery 15 and forms an explosion relief channel with a larger cavity with the through grooves 42 of the individual battery 15.

[0238] Figure 25 In the middle, the weak part is the groove 45 opened on the lower surface of the upper cover plate. A channel needs to be set on the pressure-bearing housing 13. This channel covers the weak part of each individual battery 15 (the area of ​​the upper cover plate 1 corresponding to the bottom of the groove 45) and forms a venting channel between it and the weak part of the individual battery 15.

[0239] Figure 26 and Figure 27 In the middle, the weak part is the through hole 46 opened on the upper cover plate. The through holes 46 of each individual battery 15 are connected to form an explosion relief channel. This explosion relief channel is also located between the weak part (the bottom of the through hole 46) and the pressure-bearing shell 13.

[0240] like Figure 21 As shown, the pressure-bearing housing 13 is provided with an explosion relief part 16 corresponding to the explosion relief channel (the explosion relief part 16 here can also be called an explosion-proof part, explosion-proof port or explosion relief port, etc., and is usually provided with a pressure relief valve or explosion relief membrane, etc.). When the single cell 15 thermally runs away, the thermal runaway smoke breaks through the weak part, passes through the explosion relief channel, breaks through the explosion relief part 16 and is discharged from the pressure-bearing housing 13.

[0241] In the initial stage of thermal runaway, the thermal runaway fumes can be discharged in an orderly manner through the explosion venting channel, effectively preventing them from spreading to the large-capacity battery casing and thus preventing further deterioration of the thermal runaway situation.

[0242] The strength of the pressure-bearing casing 13 needs to meet the strength requirements of the casing during thermal runaway, meaning that the pressure-bearing casing 13 needs to have good strength. This design not only effectively resists the high-pressure impact during thermal runaway with the reinforced outer encapsulation casing, greatly improving the overall safety of the large-capacity battery; especially when plastic material is used as the casing of the internal individual cells 15, the pressure-bearing casing 13 can form a robust thermal barrier. Even in the extreme case where the casing of the individual cell 15 melts, it can effectively isolate high-temperature flames and harmful gases, preventing the spread of thermal runaway and improving the safety of the large-capacity battery after thermal runaway. In addition, when plastic material is used as the casing of the internal individual cells 15, an anti-permeability membrane can be provided between each individual cell 15 and the pressure-bearing casing 13 to prevent the electrolyte inside each individual cell 15 from seeping out.

[0243] Compared to other materials, the metal pressure-bearing housing 13 is more reliable in emergency situations such as thermal runaway. It 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-bearing housing 13 does not directly contact the electrolyte, so an iron, steel, or stainless steel housing can be used. Iron housings 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 housings 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 housings 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.

[0244] like Figure 28 and Figure 29 As shown, to adopt Figure 13 Taking the single battery 15 shown as an example, in this embodiment, a clearance hole 17 is provided on the top plate of the pressure-bearing housing 13 corresponding to the polarity terminal 11 of each single battery 15; the polarity terminal 11 of each single battery 15 extends out of the clearance hole 17; the top plate area of ​​the pressure-bearing housing 13 corresponding to the clearance hole 17 is fixedly sealed with the housing of the single battery 15.

[0245] To optimize the heat dissipation performance of the aforementioned high-capacity battery, this embodiment adds a heat exchange component 14 to the high-capacity battery to exchange heat with the polarity terminal 11. The polarity terminal 11 is a key component connecting the battery's internal and external components; during charging and discharging, current flows through the polarity terminal 11 into and out of the battery. When heat is generated inside the battery, heat dissipation through the polarity terminal 11 provides a relatively direct heat conduction path. Heat can be quickly conducted from inside the battery to the polarity terminal 11, and then dissipated from the polarity terminal 11 to the external environment. Furthermore, since the polarity terminal 11 is typically located at the positive and negative terminals of the battery, these areas are often where heat is concentrated during charging and discharging. By dissipating heat from the polarity terminal 11, the temperature of these key components can be reduced more effectively.

[0246] The heat exchange component can be a heat transfer tube; each polarity terminal 11 of the individual cell 15 is provided with a through groove or through hole for installing the heat transfer tube; the heat transfer tube is fixed in the through groove or through hole of each polarity terminal 11 of the individual cell 15. By using the heat transfer tube on the polarity terminal 11, the heat generated inside the battery is conducted to the heat transfer tube through the polarity terminal 11, and then the heat transfer tube dissipates the heat to achieve heat dissipation of the battery.

[0247] The heat exchange component can also be a heat exchange device, which is disposed on top of each individual battery cell 15. A polar terminal 11 penetrates the heat exchange device, with at least a portion of its structure located within the heat exchange device's inner cavity and in direct contact with the heat exchange medium. Another portion of the polar terminal 11 is located outside the heat exchange device, serving as an electrical connection. The sidewall of the polar terminal 11 is sealed to the heat exchange device. By employing a direct heat exchange method, a portion of the polar terminal 11 is directly placed within the heat exchange medium flow cavity (the inner cavity of the heat exchange device), allowing direct contact between the polar terminal 11 and the heat exchange medium. This achieves heat exchange for the polar terminal 11, resulting in a shorter heat exchange path. The heat exchange medium directly acts on the polar terminal 11, improving the utilization efficiency of the heat exchange medium and enhancing the battery's heat exchange efficiency.

[0248] In this embodiment, an insulating sealant layer can also be provided between each individual battery cell 15 and between each individual battery cell 15 and the pressure-bearing housing 13. The insulating sealant layer is mainly laid in the space between each individual battery cell 15 and the pressure-bearing housing 13, and the heat exchange components inside the pressure-bearing housing 13 are all located within the insulating sealant layer; when there is a gap between each individual battery cell 15, the insulating sealant liquid can also penetrate into the gap to form an insulating sealant layer.

[0249] It should be noted that no insulating sealant layer is installed inside the explosion venting channel.

[0250] In this embodiment, the insulating sealant layer has at least the following advantages:

[0251] 1. Prevent condensation;

[0252] During prolonged use, condensation will form on the surface of the heat exchange components due to the temperature difference between the inside and outside. When the condensation accumulates to a certain amount, it may cause a short circuit. By laying an insulating sealant layer to completely wrap the heat exchange components, the condensation on the surface of the heat exchange components can be protected from short circuits.

[0253] II. Further improve the stability of each individual battery cell 15 within the pressure-bearing casing 13;

[0254] The insulating sealant penetrates into the gaps between each individual cell 15 and between each individual cell 15 and the pressure-bearing housing 13, which can further improve the stability of each individual cell 15 within the pressure-bearing housing 13.

[0255] use Figure 28 and Figure 29 In the structure shown, an insulating sealant layer can also be laid on the top plate of the pressure-bearing shell 13, and the heat exchange component is located inside the insulating sealant layer. When condensation occurs on the surface of the heat exchange component, the battery short circuit can be prevented under the protection of the insulating sealant layer.

Claims

1. A casing for a single battery cell, characterized in that: It is composed of an upper cover plate, a cylindrical body, and a lower cover plate; the upper cover plate, the cylindrical body, and the lower cover plate are all made of plastic. Along the height direction, from bottom to top, the inner cavity of the housing is divided into an electrode assembly support area and an electrode assembly receiving area; A first recess and a first protrusion are provided on the housing area corresponding to the electrode assembly support area; wherein the first recess is used for the first protrusion on the housing of another single cell to be embedded and fixedly connected; under the action of external force, a channel can be opened in the first recess and the first protrusion, and the channel communicates with the electrolyte area inside the single cell housing. The top cover is equipped with a connector for connecting to the connector on the adjacent single cell. Under external force, a channel can be opened in the connector, which communicates with the gas area inside the single cell casing.

2. The housing for a single battery cell according to claim 1, characterized in that: The connector is a second recess and a second protrusion provided on opposite sidewalls of the upper cover plate; wherein the second recess is used for the second protrusion of another single battery cell to be embedded and fixedly connected, and under the action of external force, a channel can be opened in the second protrusion and the second recess, which communicates with the gas area inside the cavity of the single battery cell.

3. The housing for a single battery cell according to claim 2, characterized in that: The second recess is a second blind hole opened on the first side wall of the upper cover plate; the second protrusion is a second pair of connecting pipes provided on the outer wall of the second side wall of the upper cover plate; the second pair of connecting pipes are used to be embedded in the second blind hole of another single cell and fixedly connected; the first side wall of the upper cover plate and the second side wall of the upper cover plate are parallel to each other.

4. The housing for a single battery cell according to claim 3, characterized in that: The upper cover plate has a channel that communicates with the inner cavity of the second connector; a partition is provided in the channel, and a cavity is formed between the partition and the bottom end of the second blind hole. A through hole is provided in the upper cover plate area corresponding to the cavity for communicating with the inner cavity of the single cell. Under the action of external force, the separator and the bottom of the second blind hole can be opened, so that the inner cavity of the second connector, the inner cavity of the channel, and the inner cavity of the second blind hole are all connected to the inner cavity of the single cell.

5. The housing for a single battery cell according to claim 1, characterized in that: The connector is a sub-pipe segment set on the upper surface of the upper cover plate; the sub-pipe segment is a hollow pipe; the hollow pipe and the upper cover plate have interconnected openings, and the two ends of the hollow pipe are closed ends. Two closed ends are defined as the first closed end and the second closed end, respectively; a third blind hole extending axially is opened at the first closed end; the third blind hole is used for the insertion and fixed connection of the second closed end of another single cell hollow tube; under the action of external force, the first closed end and the second closed end of the hollow tube can be opened.

6. The housing for a single-cell battery according to any one of claims 1 to 5, characterized in that: The first recess is a first blind hole formed on the first side wall of the lower cover plate; the first protrusion is a first pair of connecting pipes provided on the outer wall of the second side wall of the lower cover plate; the first pair of connecting pipes are used to be embedded in the first blind hole of another single cell and fixedly connected; the first side wall of the lower cover plate and the second side wall of the lower cover plate are parallel to each other.

7. The housing for a single battery cell according to claim 6, characterized in that: The inner surface of the lower cover plate has multiple protrusions arranged in an array. The top of the protrusions is used to support the electrode assembly, and the gap between the protrusions serves as an electrolyte flow channel.

8. The housing for a single battery cell according to claim 7, characterized in that: Under the action of external force, the bottom end of the first blind hole and the second side wall area of ​​the lower cover plate defined by the first connecting pipe can be opened and connected to the electrolyte flow channel.

9. The housing for a single battery cell according to claim 1, characterized in that: The top cover plate has an integrally formed weak section; the strength of the weak section is less than the strength of the rest of the top cover plate. When a single cell experiences thermal runaway, the thermal runaway smoke breaks through the weak section and is discharged.

10. The housing for a single battery cell according to claim 1, characterized in that: Both the first recess and the first protrusion are integral parts with the cylinder or the lower cover plate; the first recess is used for the first protrusion of another single battery cell to be embedded and fixedly connected by heat fusion; the connector is integral with the upper cover plate; the connector is used for fixedly connecting with the connector of another single battery cell by heat fusion.

11. A single-cell battery, characterized in that: Includes the casing for a single-cell battery as described in any one of claims 1 to 10.

12. The single-cell battery according to claim 11, characterized in that: The shell strength is P, where P1≤P≤P2; where P1 is the strength requirement of the shell during the formation stage and the normal charging and discharging stage of the battery; and P2 is the strength requirement of the shell during the thermal runaway stage.

13. A high-capacity battery, characterized in that: It includes a pressure-bearing housing and n individual battery cells as described in claim 11 or 12 arranged within the pressure-bearing housing, where n is an integer greater than 1; In adjacent single cells, the first protrusion of one single cell is embedded into the first recess of another single cell and fixedly connected. The first protrusion and the first recess form a channel that penetrates the electrolyte area inside the cell housing. The connector of one single cell is fixedly connected to the connector of another single cell, and the connector has a channel that penetrates the gas area inside the cell housing. The pressure-bearing shell has the strength required for the shell during the thermal runaway stage, and the pressure-bearing shell is equipped with a venting section.

14. The high-capacity battery according to claim 13, characterized in that: An explosion relief channel is formed between the weakest part of each individual battery cell and the pressure-bearing casing; The pressure-bearing shell is equipped with a venting section corresponding to the venting channel; when a single cell experiences thermal runaway, the thermal runaway flue gas breaks through the weak part, passes through the venting channel, breaks through the venting section, and exits the pressure-bearing shell.

15. The high-capacity battery according to claim 13, characterized in that: The top plate of the pressure-bearing housing has clearance holes corresponding to the polarity terminals of each individual battery; the polarity terminals of each individual battery extend out of the clearance holes; the area of ​​the top plate of the pressure-bearing housing corresponding to the clearance holes is fixedly sealed to the individual battery housing.

16. The high-capacity battery according to claim 13, characterized in that: It also includes heat exchange components that exchange heat with the polarity terminals.

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