Single battery and high-capacity battery

Abstract

The utility model discloses a single battery and a high-capacity battery. A shell of the single battery is a plastic shell, and an electrolyte storage area for storing free electrolyte and an electrode assembly accommodating area for placing an electrode assembly are arranged in the shell; a concave part and a bulge are arranged on the side wall of the barrel body corresponding to the electrolyte storage area; wherein the concave part is used for inserting a bulge on another single battery and is fixedly connected with the bulge; under the action of external force, the side wall, defined by the protrusion, of the barrel and the concave part can be opened, and then the protrusion and the concave part are both communicated with the electrolyte storage area. The high-capacity battery composed of the single batteries is low in cost and light in weight, the free electrolyte stored in the electrolyte storage area in each single battery can rapidly absorb heat through heat transfer, the battery is effectively prevented from being overheated, the thermal runaway risk is reduced, meanwhile, gas balance and / or electrolyte sharing can be achieved between the single batteries, and the service life of the battery is prolonged. The consistency of each single battery in the charging and discharging process is ensured, and the overall service life is prolonged.

Description

Technical Field

[0001] This utility model belongs to the field of batteries, specifically a single cell battery 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-cell battery in the aforementioned patent includes a casing, a sealing assembly, and a finished battery. The finished battery is installed inside the casing, and the casing has an opening. The casing has a first through hole communicating with the opening, and a pipe 01 extending along the width or length of the casing. 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. By providing the first through hole and the pipe with the second through hole on the casing of the single-cell battery, a shared pipeline 02 can be formed through this pipeline when assembling a large-capacity battery. Moreover, by covering the finished battery with the casing, existing finished battery production lines can be used, and the finished battery can be put into production with slight modifications.

[0004] 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.

[0005] 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.

[0006] 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

[0007] In order to overcome the problems of high cost and heavy weight of existing large-capacity batteries, the first aspect of this utility model provides a single-cell battery.

[0008] A single cell includes a casing and electrode components; its improvement lies in:

[0009] The shell is a plastic shell, including a cylindrical body with open ends, an upper cover assembly fixedly sealed to the upper open end of the cylindrical body, and a lower cover assembly fixedly sealed to the lower open end of the cylindrical body.

[0010] The housing contains an electrolyte storage area and an electrode assembly housing area;

[0011] The side wall of the cylinder corresponding to the electrolyte storage area is provided with a recess and a protrusion; the recess is used for the protrusion on another single cell to be inserted and fixedly connected; under the action of external force, the side wall of the cylinder enclosed by the protrusion and the recess can be opened, thereby making the protrusion and the recess connected to the electrolyte storage area.

[0012] The single-cell battery of this invention fully utilizes the electrolyte storage area within its casing, which can store a large amount of free electrolyte. The electrolyte possesses a certain thermal conductivity; during battery operation, if the temperature rises, the free electrolyte stored in the storage area can rapidly absorb heat through heat transfer, dispersing the absorbed heat throughout the entire battery 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.

[0013] Furthermore, the electrolyte storage area and the electrode assembly housing area are interconnected, allowing the electrolyte to flow and diffuse freely throughout the entire casing. When the electrode assembly is in operation, electrolyte consumption can be replenished promptly, preventing localized drying, ensuring stable internal battery reactions, and improving charge / discharge performance.

[0014] In addition, when using this single cell to assemble a large-capacity battery, this invention can also use tools to open the cylindrical area and recess of each single cell, so that gas balance and / or electrolyte sharing can be achieved between the individual cells. The differences that may exist 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.

[0015] Furthermore, the casing component of the single battery provided by this utility model is made of plastic, which has advantages such as simple structure, low cost and light weight compared with the single battery with double casing used in the background art.

[0016] Furthermore, the strength of the aforementioned casing is P, where P1 ≤ P ≤ P2; where P1 represents the strength requirement of the casing during the formation stage and normal charge / discharge stages; and P2 represents the strength requirement of the casing during the thermal runaway stage. The aforementioned single-cell battery casing is a sealed casing made of plastic, serving as a containment cavity for the electrode components and electrolyte, and has a sealing function. Simultaneously, the strength of the sealed casing needs to meet the strength requirements of the casing during the formation stage and normal charge / discharge stages; that is, the sealed casing must have a certain 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.

[0017] Furthermore, this utility model can use injection molding to integrally form the recesses and protrusions on the shell components. The processing is simple. Since the recesses and protrusions are formed at the same time as the shell components, there is no problem of dimensional deviation caused by subsequent assembly. The precision is high, which can ensure that the recesses and protrusions of each individual battery can be precisely matched, which is beneficial to the mass production and quality control of large-capacity batteries.

[0018] Furthermore, the recesses and protrusions are connected via a heat-fusion process. During this process, the plastic material melts upon heating, and upon cooling and solidification, the materials of the recesses and protrusions fuse together to form a single, integrated structure, creating a very strong bond between them. This connection method can withstand significant tensile, compressive, and shear forces, effectively preventing loosening or separation of individual battery cells during use and ensuring the structural stability of high-capacity batteries. Simultaneously, heat-fusion connections have lower precision requirements; even with slight dimensional deviations in the recesses and protrusions during production, precise connections can still be achieved, greatly improving production efficiency.

[0019] The cylindrical body of this utility model has two first side walls and two second side walls, and the protrusions, recesses, and electrolyte storage areas are arranged in the following two ways:

[0020] The first method is as follows: the protrusion, the recess, and the electrolyte storage area are all set on the first side wall of the cylinder; specifically, the recess is a blind hole set on the first side wall, and the opening of the blind hole is flush with the outer surface of one of the second side walls, and the connecting pipe is set on the end face of the first side wall and the other second side wall that is flush with the outer surface; the electrolyte storage area is a hollow part, which is set on the surface of the first side wall near the inner cavity of the cylinder.

[0021] The second method is as follows: the protrusions and recesses are set on the second side wall of the cylinder. Specifically, a protrusion is set on the inner surface of one of the second side walls, and a blind hole is opened in the protrusion. The opening of the blind hole is flush with the outer surface of the second side wall. The area inside the cylinder corresponding to the height of the protrusion is the electrolyte storage area.

[0022] The protrusion is a connecting pipe disposed on the outer surface of another second sidewall.

[0023] Furthermore, in the second method described above, in order to better utilize the space inside the cylinder to divide the electrolyte storage area and the electrode assembly receiving area, the protrusion is closely attached to the inner surface of one of the first sidewalls. The cylinder also includes a partition parallel to the first sidewall. The partition is clamped between the protrusion and the other second sidewall, thereby dividing the inside of the cylinder into the electrolyte storage area and the electrode assembly receiving area. The partition has multiple hollow areas so that the electrolyte storage area and the electrode assembly receiving area are interconnected.

[0024] Furthermore, it also includes at least one support rib, each support rib being connected to the partition on one side and pressing against the first sidewall where the protrusion is in close contact with the other side. The presence of this support rib can, on the one hand, suppress the expansion of the electrode assembly, and on the other hand, increase the strength of the cylinder itself.

[0025] The second aspect of this utility model provides a high-capacity battery, including a housing and n individual batteries, where n is an integer greater than 1.

[0026] The strength of the enclosure meets the strength requirements of the shell during the thermal runaway stage, and the enclosure is equipped with an explosion vent.

[0027] In adjacent individual cells, the protrusion of one individual cell is inserted into the recess of another individual cell and fixedly connected by heat fusion. After the recess and protrusion of the adjacent individual cells are opened, the internal cavities of each individual cell are interconnected, and the recess and protrusion of the first and last individual cells must remain sealed with the internal cavity of the box.

[0028] The casing of this high-capacity battery is a pressure-bearing casing, and its strength needs to meet the strength requirements of the casing during the thermal runaway stage; that is, the pressure-bearing casing is required to have good strength to ensure that during the thermal runaway stage, the pressure-bearing casing can form a solid barrier, effectively isolate high-temperature flames and harmful gases, prevent the spread of thermal runaway, and improve the safety of the high-capacity battery after thermal runaway.

[0029] Furthermore, the top plate of the casing 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 casing corresponding to the clearance holes is fixedly sealed to the individual battery casing.

[0030] In this utility model, the polarity terminals of each individual battery extend out of the casing to facilitate electrical connection between individual batteries, as well as electrical connection between the large-capacity battery itself and external electrical equipment.

[0031] Meanwhile, in this invention, by using tools to open the cylindrical area and recessed part defined by the protrusion of each individual battery, gas balance and / or electrolyte sharing can be achieved between the individual batteries. The differences that may have existed can be effectively improved, ensuring the consistency of each individual battery during the charging and discharging process, extending the overall service life, and improving the performance of large-capacity batteries.

[0032] Furthermore, the portions of the polarity terminals of each individual battery cell that extend beyond the casing cooperate with the heat exchange components to achieve temperature control for each individual battery cell. During the operation of a large-capacity battery, heat easily accumulates at the polarity terminals due to current conduction. The heat exchange components can promptly remove this heat, ensuring that the polarity terminals remain within a suitable operating temperature range. This not only helps maintain the performance stability of the individual batteries within the large-capacity battery and reduces battery performance degradation caused by excessively high temperatures, but also further enhances the overall safety and reliability of the large-capacity battery, avoiding potential failures caused by localized overheating.

[0033] The beneficial effects of this utility model are:

[0034] The single-cell battery of this utility model uses a plastic casing, which enables the large-capacity battery constructed from it to have a lower cost and lighter weight.

[0035] Meanwhile, to improve the safety performance of the large-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 large-capacity battery.

[0036] Secondly, the single-cell battery in this invention fully utilizes the electrolyte storage area within its casing, which can store a large amount of free electrolyte. Since electrolyte has a certain thermal conductivity, during battery operation, if the temperature rises, the free electrolyte stored in the storage area can rapidly absorb heat through heat transfer, dispersing the absorbed heat throughout the entire battery 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.

[0037] Furthermore, the electrolyte storage area and the electrode assembly housing area are interconnected, allowing the electrolyte to flow and diffuse freely throughout the entire casing. When the electrode assembly is in operation, electrolyte consumption can be replenished promptly, preventing localized drying, ensuring stable internal battery reactions, and improving charge / discharge performance.

[0038] Furthermore, after the individual cells are connected by recesses and protrusions, this invention can also use tools to open the cylindrical side wall area and blind hole defined by the protrusions of each individual cell. In this way, gas balance and / or electrolyte sharing can be achieved between the individual cells, and the differences that may have existed 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. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the structure of a large-capacity battery in the background art;

[0040] Figure 2 This is a schematic diagram of a single battery cell;

[0041] Figure 3 for Figure 1 Horizontal sectional view;

[0042] Figure 4 This is a schematic diagram of the cylinder structure in Example 1;

[0043] Figure 5 This is a schematic diagram of the cylinder structure in Example 2. Figure 1 ;

[0044] Figure 6 This is a schematic diagram of the cylinder structure in Example 2. Figure 2 ;

[0045] Figure 7 This is a schematic diagram of a high-capacity battery.

[0046] The attached figures are labeled as follows:

[0047] 01-Pipeline, 02-Shared Pipeline, 1-Shell, 11-Cylinder, 111-First Side Wall, 112-Second Side Wall, 12-Upper Cover Assembly, 13-Lower Cover Assembly, 131-Boss, 132-Electrolyte Flow Channel, 14-Electrolyte Storage Area, 15-Electrode Assembly Reception Area, 2-Blind Hole, 3-Connecting Pipe, 4-Protrusion, 5-Partition, 6-Support Rib, 100-Single Cell, 200-Box, 300-Explosion Vent, 400-Heat Exchange Component. Detailed Implementation

[0048] To make the above-mentioned objectives, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0049] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0050] In the description of this utility model, it should be noted that the terms "top," "bottom," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model 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 this utility model. 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.

[0051] Example 1

[0052] This embodiment provides a single-cell battery 100, such as Figure 2 and 3 As shown, it includes a housing 1 and an electrode assembly;

[0053] The shell is made of plastic. The shell 1 includes a cylindrical body 11 with open ends, an upper cover assembly 12 fixedly sealed to the upper open end of the cylindrical body, and a lower cover assembly 13 fixedly sealed to the lower open end of the cylindrical body 11.

[0054] The housing 1 has an electrolyte storage area 14 and an electrode assembly receiving area 15; specifically, the electrolyte storage area 14 and the electrode assembly receiving area 15 are distributed according to the width direction or thickness direction of the single cell.

[0055] A recess and a protrusion are provided on the side wall of the cylinder 11 corresponding to the electrolyte storage area; the recess is used for the protrusion on another single cell to be inserted and fixedly connected; under the action of external force, the side wall of the cylinder enclosed by the protrusion and the recess can be opened, thereby making the protrusion and the recess connected to the electrolyte storage area.

[0056] In this embodiment, the single-cell battery fully utilizes the electrolyte storage area within its casing to store a large amount of free electrolyte. The electrolyte possesses a certain thermal conductivity; during battery operation, if the temperature rises, the free electrolyte stored in the storage area can rapidly absorb heat through heat transfer, dispersing the absorbed heat throughout the entire single-cell battery 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.

[0057] Furthermore, the electrolyte storage area and the electrode assembly housing area are interconnected, allowing the electrolyte to flow and diffuse freely throughout the entire casing. When the electrode assembly is in operation, electrolyte consumption can be replenished promptly, preventing localized drying, ensuring stable internal battery reactions, and improving charge / discharge performance.

[0058] In addition, when using this single cell to assemble a large-capacity battery, this invention can also use tools to open the cylindrical area and recess of each single cell, so that gas balance and / or electrolyte sharing can be achieved between the individual cells. The differences that may exist 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.

[0059] Furthermore, the casing component of the single battery provided by this utility model is made of plastic, which has advantages such as simple structure, low cost and light weight compared with the single battery with double casing used in the background art.

[0060] It should be noted that the plastic material selected in this utility model should have the following properties:

[0061] First, it must have sufficient strength to ensure the stability of the battery structure;

[0062] Second, it has chemical corrosion resistance and can resist the corrosion of electrolytes;

[0063] 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.

[0064] 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.

[0065] The plastic material used can be the same material used in existing plastic-cased single-cell batteries, or the plastic material disclosed in Chinese patents CN106543551A and CN106977894A.

[0066] In this embodiment, the lower cover assembly and the cylinder 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. Moreover, during the molding process, the material is evenly distributed and tightly bonded, resulting in a stronger connection between the lower cover assembly and the cylinder, and higher overall structural strength.

[0067] In this embodiment, the top cover assembly 12 and the cylinder 11 can be connected by a heat-sealing method. Heat-sealing ensures a continuous, uniform, and tight connection between the top cover and the cylinder, resulting in extremely high stability. External water, dust, and other impurities cannot enter the battery, providing excellent protection for the electrode assembly and ensuring the battery's performance and lifespan. Furthermore, the heat-sealing process is simple, and the parameters are easy to control.

[0068] like Figure 4 As shown, in this embodiment, the cylinder 1 includes two first sidewalls 111 and two second sidewalls 112, wherein the first sidewall 111 is the small end face of the cylinder and the second sidewall 112 is the large end face of the cylinder; a blind hole 2 (i.e., a recess) is provided on the end face of the first sidewall 111 that is flush with the outer surface of one of the second sidewalls 112, and at least one connecting pipe 3 (i.e., a protrusion) is provided on the end face of the first sidewall 11 that is flush with the outer surface of the other second sidewall 12, and a hollow portion is provided on the surface of the first sidewall near the inside of the cylinder 11, which serves as an electrolyte storage area 14.

[0069] Since the blind hole, the connecting pipe and the electrolyte storage area are all located on the first side wall 111 of the cylinder in this embodiment, the first side wall 111 is required to be thick. In order to save materials, when the cylinder is injection molded, the thickness of the other side walls is relatively thin except for the first side wall with the electrolyte storage area 14.

[0070] In other words, the connecting pipe 3 and the blind hole 2 are integrally formed on the first side wall 111. The so-called hollow part can be a through hole with an L-shaped cross-section, or it can be a large pit directly set on the inner surface of the first side wall.

[0071] Because the shell in this embodiment is made of plastic, the cylindrical body with blind holes and connecting pipes can be integrally molded using injection molding. During injection molding, the dimensions of the mold cavity can be precisely controlled, ensuring high dimensional accuracy of the blind holes and connecting pipes during molding, guaranteeing precise fit with other individual cells. 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 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 cells, after the connecting pipe of one cell is inserted into the blind hole of another cell, 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. When the large-capacity battery is subjected to external forces such as vibration, impact, and compression, it effectively prevents the connection between individual cells 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.

[0072] from Figure 2 and Figure 3 As can be seen from the figure, in this embodiment, at least one blind hole 2 and at least one connecting pipe 3 are respectively located on the two parallel end faces of the first sidewall 111.

[0073] In some other embodiments, at least one blind hole 2 and at least one connecting pipe 3 may be provided on one end face of the first sidewall 111, and at least one connecting pipe 3 and at least one blind hole 2 may be provided on the other end face of the first sidewall 111.

[0074] In this embodiment, when assembling large-capacity batteries, operators can easily distinguish the correspondence between blind holes and connecting pipes, enabling them to quickly and accurately connect the individual battery cells. However, when both blind holes and connecting pipes are present on the same sidewall, operators need to be more careful in distinguishing which blind hole corresponds to which connecting pipe during assembly. A slight oversight can lead to mismatches, resulting in reduced assembly efficiency.

[0075] Preferably, in order to further reduce costs, the strength of each individual battery casing in this embodiment 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. During the formation stage and the normal charge / discharge process, the battery undergoes a series of chemical reactions and physical changes. During this process, certain pressure and heat are generated inside the battery. The casing needs to have sufficient strength to withstand this pressure and heat to ensure the smooth progress of the formation process and the normal use of the battery.

[0076] 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.

[0077] Under the premise of meeting the above strength requirements, in this embodiment, the thickness of the shell 1 (cylinder, upper cover plate, and lower cover plate) is h, where h is less than h0, and h0 is the thickness of a traditional single-cell battery plastic shell; the thickness of a traditional single-cell battery plastic shell is typically 5-8 mm. In this embodiment, the shell thickness can be between 1-4 mm. By reducing the thickness of the shell of a traditional single-cell battery 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.

[0078] Preferably, in this embodiment, as Figure 3 As shown, for ease of processing and manufacturing, the cylinder 11 and the lower cover assembly 13 can be integrally formed. The inner surface of the lower cover assembly 13 is provided with multiple protrusions 131 arranged in an array. The top of the protrusions 131 is used to support the electrode assembly, and the gap between the protrusions 131 serves as an electrolyte flow channel 132.

[0079] The regularly arranged protrusions 131 provide stable and evenly distributed support points for the electrode assembly, preventing deformation or damage caused by excessive local stress. Furthermore, the gaps between the protrusions 131 serve as electrolyte flow channels 132, allowing the electrolyte to be evenly distributed around the electrode assembly, ensuring that all electrodes are in full contact with the electrolyte.

[0080] Example 2

[0081] This embodiment provides another type of single-cell battery, such as Figure 5 and Figure 6As shown, the single-cell battery structure differs from that of Embodiment 1 in that the recess and the protrusion are integrally formed on the second sidewall 112; its specific structure is as follows: a protrusion 4 is provided on the inner surface of one of the second sidewalls 112, and a blind hole 2 is opened in the protrusion 4. The opening of the blind hole 2 is flush with the outer surface of the second sidewall 112; the area inside the cylinder corresponding to the height of the protrusion 4 is the electrolyte storage area 14; the protrusion is a connecting pipe 3 provided on the outer surface of the other second sidewall 112.

[0082] Bumps have the following two forms:

[0083] The first type is a block structure with multiple protrusions 4 distributed along the height direction of the cylinder 11. Each protrusion 4 has a blind hole 2.

[0084] The second type is a strip-shaped structure, usually one, which extends along the height direction of the cylinder. Multiple blind holes 2 are opened on the protrusion 4 along the height direction.

[0085] Preferably, in this embodiment, in order to better utilize the space inside the cylinder 11 to divide the electrolyte storage area and the electrode assembly receiving area, the protrusion 4 is closely attached to the inner surface of one of the first sidewalls 111. The cylinder 11 also includes a partition 5 parallel to the first sidewall 111. The partition 5 is sandwiched between the protrusion 4 and the other second sidewall 112 to divide the inside of the cylinder 11 into an electrolyte storage area 14 and an electrode assembly receiving area 15. The partition 5 is provided with multiple hollow areas so that the electrolyte storage area and the electrode assembly receiving area are interconnected.

[0086] In addition to the partition 5, this embodiment may also preferably provide at least one supporting rib 6. Each supporting rib 6 is connected to the partition 5 on one side and presses against the first sidewall 111 where the protrusion 4 is in close contact with it on the other side. Each supporting rib 6 is provided with a through hole at the position corresponding to the blind hole 2. The presence of the supporting rib 6 can suppress the expansion of the electrode assembly on the one hand, and improve the strength of the cylinder itself on the other hand.

[0087] Example 3

[0088] Based on the single-cell batteries of Examples 1 and 2, this embodiment provides a high-capacity battery, such as... Figure 7 As shown, it includes a housing 200 and 12 individual battery cells 100. In other embodiments, the number of individual battery cells 100 can be adjusted according to actual needs.

[0089] The enclosure 200 is equipped with an explosion vent 300; all n individual batteries 100 are located inside the enclosure 200.

[0090] In adjacent individual cells 100, the protrusion of one individual cell 100 is inserted into the recess of another individual cell 100 and fixedly connected by heat fusion. After the recess and protrusion (i.e., blind hole 2 and connecting pipe 3) of the adjacent individual cells 100 are opened, the inner cavities of each individual cell are interconnected (i.e., the electrolyte storage areas of each individual cell 100 are interconnected), and the recess and protrusion of the first and last individual cells must be sealed with the inner cavity of the box (i.e., the blind hole 2 and connecting pipe 3 of the first and last individual cells 100 that are not involved in the interlocking connection).

[0091] It should be noted that:

[0092] 1. The blind hole 2 and connecting pipe 3 of the first and last single cells 100 that are not involved in the plug-in connection, wherein the connecting pipe 3 or blind hole 2 on the last single cell does not need to be opened, and the opening of the blind hole 2 or connecting pipe 3 of the first single cell is sealed. The sealing method can be to use a plug to achieve a seal with the inner cavity of the box by interference fit or hot melting and then inserting it into the blind hole or connecting pipe.

[0093] 2. In order to improve the regularity of the entire large-capacity battery and the energy density of the large-capacity battery, this embodiment can remove the connecting pipes that are not involved in the insertion in the first or last single cell in advance.

[0094] 3. If the blind hole 2 and the connecting pipe 3 are located near the lower open end of the cylinder 11, multiple individual cells 100 can be in one electrolyte system when the blind hole 2 and the connecting pipe 3 are opened; if the blind hole 2 and the connecting pipe 3 are located near the upper open end of the cylinder 11 (i.e., when the liquid level in the electrolyte storage area is lower than the height of the central axis of the blind hole and the connecting pipe), multiple individual cells 100 can be in one gas balance system when the blind hole 2 and the connecting pipe 3 are opened; if the blind hole 2 and the connecting pipe 3 are located near both the upper and lower open ends of the cylinder 11, multiple individual cells can be in one electrolyte system and one gas balance system simultaneously when both the blind hole 2 and the connecting pipe 3 are opened.

[0095] This embodiment uses the casing of the large-capacity battery as the core pressure-bearing casing. The strength of the casing needs to meet the strength requirements of the shell during thermal runaway, that is, the casing needs to have good strength. This design not only effectively resists the high-pressure impact during thermal runaway with the reinforced casing, greatly improving the overall safety of the large-capacity battery; especially when a less strong plastic shell is used as the inner individual cell shell, the casing can form a robust thermal barrier. Even in the extreme case of the individual cell shell melting, it can effectively isolate high-temperature flames and harmful gases, prevent the spread of thermal runaway, and improve the safety of the large-capacity battery after thermal runaway. In addition, when plastic material is used as the inner individual cell shell, an anti-seepage membrane can also be provided between each individual cell and the pressure-bearing casing to prevent the electrolyte inside each individual cell from seeping out.

[0096] Compared to other materials, metal pressure tanks are more reliable in emergencies such as thermal runaway. They can withstand greater impact and destructive forces, reducing the likelihood of accidents and protecting the safety of personnel and surrounding equipment. In this embodiment, the pressure tank does not directly contact the electrolyte, so an iron, steel, or stainless steel shell can be used. Iron shells offer advantages in strength and cost, making them a viable option in scenarios where cost is a primary concern and strength requirements are not particularly stringent. Steel shells offer relatively high strength, providing more reliable protection for the battery and are suitable for applications with high safety and structural strength requirements. Stainless steel shells not only possess good strength properties but also excellent corrosion resistance, making them ideal for battery applications facing humid or corrosive environments. This effectively extends battery life and ensures stable operation in complex environments.

[0097] In this embodiment, the top of the housing 200 is provided with clearance holes corresponding to the polarity terminals of each individual battery; the polarity terminals of each individual battery extend out of the corresponding clearance holes, and the polarity terminals and clearance holes are insulated and sealed. Extending the polarity terminals of the individual batteries out of the housing facilitates the electrical connection between individual batteries and the electrical connection between large-capacity batteries and external devices.

[0098] Of course, in some other embodiments, the polarity terminals of a single battery cell may not extend out of the casing.

[0099] Example 4

[0100] To optimize the heat dissipation performance of the large-capacity battery in Embodiment 3, this embodiment adds a heat exchange component 400 to the aforementioned large-capacity battery to exchange heat at the polarity terminals. As a key component connecting the battery's internal and external components, the polarity terminals allow current to flow in and out of the battery during charging and discharging. When heat is generated inside the battery, heat dissipation through the polarity terminals provides a relatively direct heat conduction path. Heat can be rapidly conducted from inside the battery to the polarity terminals, and then dissipated from the polarity terminals to the external environment. Furthermore, since the polarity terminals are 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 terminals, the temperature of these critical components can be reduced more effectively.

[0101] The heat exchange component 400 can be a heat transfer tube; each individual cell has a through slot or through hole on its polarity terminal for installing the heat transfer tube; the heat transfer tube is fixed in the through slot or through hole of each individual cell's polarity terminal. Using the heat transfer tube on the polarity terminal, the heat generated inside the cell is conducted through the polarity terminal to the heat transfer tube, and then the heat transfer tube dissipates the heat, thus achieving heat dissipation for the cell.

[0102] The heat exchange component 400 can also be a heat exchange device, which is disposed on top of each individual battery cell. A polar terminal 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's structure is located outside the heat exchange device, serving as an electrical connection. The sidewall of the polar terminal is sealed to the heat exchange device. This direct heat exchange method places a portion of the polar terminal's structure directly within the heat exchange medium's flow cavity (the inner cavity of the heat exchange device), allowing direct contact between the polar terminal and the heat exchange medium. This achieves heat exchange at the polar terminal, resulting in a shorter heat exchange path. The heat exchange medium directly acts on the polar terminal, improving the utilization efficiency of the heat exchange medium and enhancing the battery's heat exchange efficiency.

Claims

1. A single-cell battery, comprising a casing and an electrode assembly; characterized in that: The shell is a plastic shell, including a cylindrical body with open ends, an upper cover assembly fixedly sealed to the upper open end of the cylindrical body, and a lower cover assembly fixedly sealed to the lower open end of the cylindrical body. The housing contains an electrolyte storage area and an electrode assembly housing area; The side wall of the cylinder corresponding to the electrolyte storage area is provided with a recess and a protrusion; the recess is used for the protrusion on another single cell to be inserted and fixedly connected; under the action of external force, the side wall of the cylinder enclosed by the protrusion and the recess can be opened, thereby making the protrusion and the recess connected to the electrolyte storage area.

2. The single-cell battery according to claim 1, characterized in that: Both the recess and the protrusion are integral with the housing components; the recess is used for the protrusion of another single cell to be inserted and fixedly connected by heat fusion.

3. The single-cell battery according to claim 1, characterized in that: The strength of the single-cell battery casing is P, where P1≤P≤P2; where P1 is the strength requirement of the casing during the formation stage and the normal charging and discharging stage of the battery; and P2 is the strength requirement of the casing during the thermal runaway stage.

4. The single-cell battery according to any one of claims 1 to 3, characterized in that: The cylinder includes two first side walls and two second side walls; The recess is a blind hole provided on the first side wall, and the opening of the blind hole is flush with the outer surface of one of the second side walls. The connecting pipe is provided on the end face of the first side wall and the other second side wall that is flush with the outer surface. The electrolyte storage area is a hollow section, which is located on the surface of the first side wall near the inner cavity of the cylinder.

5. The single-cell battery according to any one of claims 1 to 3, characterized in that: The cylinder includes two first side walls and two second side walls; One of the second sidewalls has a protrusion on its inner surface, and a blind hole is formed in the protrusion. The opening of the blind hole is flush with the outer surface of the second sidewall. The area inside the cylinder corresponding to the height of the protrusion is the electrolyte storage area. The protrusion is a connecting pipe disposed on the outer surface of another second sidewall.

6. The single-cell battery according to claim 5, characterized in that: The protrusion is closely attached to the inner surface of one of the first sidewalls. The cylinder also includes a partition parallel to the first sidewall. The partition is clamped between the protrusion and the other second sidewall, thereby dividing the cylinder into an electrolyte storage area and an electrode assembly receiving area. The partition has multiple hollow areas so that the electrolyte storage area and the electrode assembly receiving area are interconnected.

7. The single-cell battery according to claim 6, characterized in that: It also includes at least one support rib, each support rib is connected to the partition on one side and abuts against the first sidewall where the protrusion is tightly attached on the other side, and each support rib is provided with a through hole at the position corresponding to the blind hole.

8. A high-capacity battery, comprising a housing and n individual battery cells as described in any one of claims 1 to 7, wherein n is an integer greater than 1; The strength of the enclosure meets the strength requirements of the shell during the thermal runaway stage, and the enclosure is equipped with an explosion vent. In adjacent individual cells, the protrusion of one individual cell is inserted into the recess of another individual cell and fixedly connected. After the recesses and protrusions of adjacent individual cells are opened, the internal cavities of each individual cell are interconnected. The recesses and protrusions of the first and last individual cells must remain sealed with the internal cavity of the box.

9. The high-capacity battery according to claim 8, characterized in that: The top plate of the casing 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 casing corresponding to the clearance holes is fixedly sealed to the individual battery casing.

10. The high-capacity battery according to claim 8 or 9, characterized in that: The portion of the polarity terminal of each individual battery cell that extends out of the housing cooperates with the heat exchange component to achieve temperature control of each individual battery cell.

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