Cylinder and shell for single battery, single battery and battery pack

Abstract

The invention belongs to the field of batteries, and particularly relates to a cylinder for a single battery, a shell, the single battery and a battery pack. And the heating problem of the single battery in the use process is relieved. The cylinder for the single battery comprises an electrode assembly accommodating cavity and an electrolyte storage cavity which are communicated with each other; the shell comprises the barrel, the single batteries comprise the shell, and the battery pack comprises the single batteries; at least one electrolyte storage cavity is arranged in the battery cylinder, the free electrolyte is stored in the electrolyte storage cavity, the electrolyte has certain heat conduction capability, and when the battery runs, if the temperature rises, the free electrolyte stored in the electrolyte storage cavity can quickly absorb heat through heat transfer and disperse the absorbed heat to the whole shell, so that the heat conduction capability of the battery is improved, and the service life of the battery is prolonged. And the light is emitted through the surface of the shell. The battery is effectively prevented from overheating, the thermal runaway risk is reduced, the temperature is accurately regulated and controlled, and the battery performance is maintained.

Description

Technical Field

[0001] This invention belongs to the field of batteries, specifically a cylindrical body, shell, single cell, and battery pack for a single battery. Background Technology

[0002] Individual battery cells heating up during use is a relatively common phenomenon. However, if not addressed promptly, the consequences can be very serious. When a battery cell heats up, the internal chemical reactions accelerate, generating even more heat. If this heat cannot be dissipated in time, the battery temperature will continue to rise. As the temperature continues to rise, the internal pressure of the battery will also gradually increase. In this situation, thermal runaway is highly likely to occur.

[0003] Thermal runaway can have a series of serious consequences. First, the battery may explode, releasing enormous amounts of energy and causing severe damage to surrounding people and equipment. Second, thermal runaway can also trigger a fire that spreads rapidly and is difficult to control, potentially leading to a serious safety accident. Summary of the Invention

[0004] The purpose of this invention is to provide a cylindrical body, housing, single cell, and battery pack for a single battery cell, thereby mitigating the heat generation problem of the single battery cell during use.

[0005] The first aspect of the present invention provides a cylindrical body for a single battery, characterized in that it includes a first chamber and at least one second chamber; the first chamber serves as an electrode assembly receiving chamber for mounting the electrode assembly; the second chamber serves as an electrolyte storage chamber for storing free electrolyte; wherein the first chamber and the second chamber are connected.

[0006] This invention provides at least one electrolyte storage chamber within a battery casing (with open ends). The electrolyte storage chamber is interconnected with the electrode assembly housing chamber. Free electrolyte is stored within the electrolyte storage chamber. This electrolyte possesses a certain thermal conductivity; during battery operation, if the temperature rises, the free electrolyte stored in the storage chamber can rapidly 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.

[0007] Furthermore, the electrolyte storage chamber and the electrode assembly housing chamber 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.

[0008] Furthermore, the aforementioned single-cell battery casing includes a separator that divides the inner cavity of the casing into a first chamber and a second chamber. The separator has multiple perforated areas that allow the first chamber and the second chamber to communicate with each other.

[0009] The inner cavity of the cylinder is divided into a first chamber and a second chamber by a partition. The electrode assembly is installed in the first chamber. The partition provides physical support for the electrode assembly, effectively maintaining its relative position and preventing displacement, shaking, or even damage due to external forces such as vibration or collision within the shell. Simultaneously, the perforated areas on the partition ensure the flow of electrolyte between the first and second chambers.

[0010] Furthermore, multiple stiffening ribs can be provided on the inner wall of at least one side wall of the cylinder, with the space between adjacent stiffening ribs serving as a second chamber. In addition to constructing the second chamber, these stiffening ribs can also provide additional structural support for the cylinder, enhancing its own strength and rigidity, effectively resisting external forces such as compression and collision, and further ensuring the safety of the electrode components inside the single battery cell.

[0011] To further optimize battery charge and discharge performance, multiple ribs are arranged on two parallel side walls of the cylinder, with the ribs on the two side walls being symmetrical. From the perspective of electrolyte distribution, the second chambers symmetrically arranged on opposite side walls ensure that the electrolyte permeates evenly from both sides into the electrode assembly during battery charge and discharge, greatly improving the uniformity of the internal reaction of the battery and further optimizing battery charge and discharge performance.

[0012] In terms of structural strength, multiple stiffening plates symmetrically arranged on opposite sidewalls can evenly distribute external forces, effectively reduce the risk of cylinder deformation, and significantly improve the reliability and durability of the battery.

[0013] Furthermore, the length direction of the cylinder is defined as the x-direction, the width direction as the y-direction, and the height direction as the z-direction; both side walls are parallel to the yz plane; each stiffener extends along the z-direction, and multiple stiffeners are arranged along the y-direction.

[0014] In terms of electrolyte distribution, uniform distribution in both height and width directions can be achieved, greatly improving the uniformity of the internal reaction of the battery and further optimizing the battery's charge and discharge performance. Regarding structural strength, it can effectively disperse external forces in all directions, resist casing bending and torsional deformation, and prevent internal short circuits. In terms of manufacturing process, the mold design is simple, the processing precision is easily controlled, improving production efficiency and reducing costs.

[0015] Furthermore, the battery includes a partition installed in the inner cavity of the cylinder, which divides the inner cavity into a first chamber and a second chamber. The partition has multiple hollow areas to allow the first chamber and the second chamber to communicate. In the second chamber, multiple stiffening plates are provided, which extend along the z-direction. The two sides of each stiffening plate abut against the inner wall of the cylinder and the partition, respectively. The combination of the stiffening plates and the partition can further improve the stability and reliability of the battery, while greatly improving the overall strength of the cylinder.

[0016] A second aspect of the present invention provides a housing for a single battery, which is formed by an upper cover plate, a cylindrical body and a lower cover plate, wherein the cylindrical body is the aforementioned cylindrical body for a single battery; the upper cover plate, the cylindrical body and the lower cover plate are all made of plastic.

[0017] Plastic materials are easy to process. For example, through processes such as injection molding, shells with complex shapes can be quickly manufactured, reducing manufacturing difficulty and cost, improving production efficiency, and facilitating large-scale production.

[0018] Furthermore, the inner wall 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.

[0019] 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.

[0020] Furthermore, the upper cover plate has a stepped structure along its edge. This stepped structure serves as a positioning structure for the open end of the cylinder and is sealed to the open end of the cylinder via heat fusion. The stepped structure along the edge of the upper cover plate positions the open end of the cylinder, ensuring precise and close assembly. The heat fusion seal is efficient and tight, preventing impurities from entering and protecting battery performance and lifespan.

[0021] 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.

[0022] The aforementioned single-cell battery casing is a sealed plastic casing that serves as a cavity for the electrode assembly 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 stage 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 stage. Compared to existing finished plastic-cased single-cell batteries, this single-cell battery has a lower cost.

[0023] A third aspect of the present invention provides a single-cell battery, characterized in that it includes the aforementioned casing for the single-cell battery.

[0024] A fourth aspect of the present invention provides a battery pack, characterized in that: it includes a pressure-bearing housing and n individual batteries as described above, wherein n is an integer greater than 1; the n individual batteries are arranged in the pressure-bearing housing; wherein the strength of the pressure-bearing housing meets the strength requirements of the casing during the thermal runaway stage, and the pressure-bearing housing is provided with a vent.

[0025] The outer casing of the battery pack of the present invention 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 battery pack after thermal runaway.

[0026] Furthermore, the aforementioned battery pack also includes a heat exchange component that exchanges heat with the polarity terminals.

[0027] During battery pack operation, heat can easily accumulate at the polarized terminals due to current conduction. Heat exchange components can promptly remove this heat, ensuring the polarized terminals remain within a suitable operating temperature range. This not only helps maintain the stable performance of individual cells within the battery pack and reduces performance degradation caused by excessive temperature, but also further enhances the overall safety and reliability of the battery pack, preventing potential malfunctions caused by localized overheating.

[0028] The beneficial effects of this invention are:

[0029] This invention incorporates at least one electrolyte storage chamber within the battery casing, which is interconnected with the electrode assembly housing chamber. Free electrolyte is stored within the storage chamber. This electrolyte possesses a certain thermal conductivity; during battery operation, if the temperature rises, the free electrolyte stored in the storage chamber can rapidly absorb heat through heat transfer, dispersing the absorbed heat throughout the casing and dissipating it through the casing surface. This not only effectively prevents localized overheating and reduces the risk of thermal runaway, significantly improving battery safety and reliability, but also precisely controls the battery's operating temperature, ensuring stable operation within a suitable temperature range and maintaining high battery performance. Furthermore, the interconnectedness of the electrolyte storage chamber and the electrode assembly housing chamber allows the electrolyte to flow and diffuse freely throughout the casing. During electrode assembly operation, the consumed electrolyte can be replenished promptly, effectively preventing localized areas from having excessively low electrolyte concentrations or drying out. This ensures the consistency and stability of the internal battery reactions, significantly improving the battery's charge and discharge performance. Attached Figure Description

[0030] Figure 1This is a first-view exploded structural diagram of the single battery casing in Example 1;

[0031] Figure 2 This is a partial structural diagram of the single battery casing in Example 1;

[0032] Figure 3 This is a second-view exploded structural diagram of the single-cell battery casing in Example 1;

[0033] Figure 4 This is a schematic diagram of the exploded structure of the single battery casing in Example 2;

[0034] Figure 5 This is a schematic diagram of the exploded structure of the single battery casing in Example 3;

[0035] Figure 6 This is a schematic diagram of the battery pack structure in Example 5;

[0036] Figure 7 This is a schematic diagram of the exploded structure of the battery pack in Example 5.

[0037] The attached figures are labeled as follows:

[0038] 1. Top cover plate; 11. Stepped structure; 2. Cylinder body; 3. Bottom cover plate; 31. Boss; 4. Partition plate; 5. First chamber; 6. Second chamber; 7. Rib plate; 8. Individual cell; 9. Pressure tank; 10. Heat exchange components; 12. Permeable membrane. Detailed Implementation

[0039] 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.

[0040] 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.

[0041] 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.

[0042] The present invention provides a cylindrical body for a single battery. Unlike conventional single battery cylindrical bodies, the present invention integrates a separate electrolyte storage cavity inside the cylindrical body. The electrolyte storage cavity stores free electrolyte, and the electrolyte storage cavity is interconnected with the electrode assembly receiving cavity.

[0043] For ease of description in this invention, the electrode assembly receiving cavity can be defined as the first chamber for installing the electrode assembly; and the electrolyte storage cavity can be defined as the second chamber for storing the free electrolyte.

[0044] The first and second chambers of this invention are interconnected, allowing the electrolyte to flow and diffuse freely throughout the casing. During electrode assembly operation, the electrolyte consumption can be replenished promptly, effectively preventing localized areas from becoming too low in electrolyte concentration or drying out. This ensures the consistency and stability of the internal battery reaction, significantly improving the battery's charge and discharge performance. Furthermore, the electrolyte possesses a certain thermal conductivity; if the temperature rises during battery operation, the electrolyte stored in the second chamber can rapidly absorb heat through heat transfer. Because the second and first chambers are interconnected, the electrolyte can transfer heat over a larger space, dispersing the absorbed heat throughout the casing and dissipating it through the casing surface. This effectively prevents localized overheating of the battery, reduces the risk of thermal runaway, greatly improves battery safety and reliability, and allows for precise control of the battery's operating temperature, ensuring stable operation within a suitable temperature range and maintaining high battery performance.

[0045] Meanwhile, integrating the first and second chambers into a single cylindrical structure reduces the number of components and assembly steps compared to having a separate electrolyte storage chamber outside the cylinder. This not only lowers the manufacturing process difficulty and cost but also improves production efficiency, facilitating large-scale industrial production.

[0046] This invention can employ various methods to form a first chamber and a second chamber within the inner cavity of the cylinder. For example, a partition can be installed inside the cylinder to divide the inner cavity into two types of chambers, serving as the first chamber and the second chamber, respectively. To ensure smooth flow of electrolyte between the two chambers, a perforated area needs to be provided on the partition to allow for communication between the two chambers. Alternatively, multiple ribs can be provided on the inner wall of at least one side wall of the cylinder, with the space between adjacent ribs serving as an electrolyte storage chamber.

[0047] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0048] Example 1

[0049] This embodiment is a single-cell battery, including a casing, the casing structure of which is as follows: Figure 1 As shown, it is composed of an upper cover plate 1, a cylinder 2, and a lower cover plate 3.

[0050] For ease of description, we define the length direction of the shell as the x-direction, the width direction as the y-direction, and the height direction as the z-direction.

[0051] As shown in the figure, this embodiment has two partitions 4 parallel to the yz plane inside the cylinder, dividing the inner cavity of the single battery casing (inner cavity of the cylinder) into three chambers. The two outer chambers are designated as the second chamber 6, and the middle chamber is designated as the first chamber 5. To ensure smooth flow of electrolyte between the first chamber 5 and the second chamber 6, multiple through holes are provided on the partitions 4 to achieve interconnection between the two chambers, allowing the free electrolyte stored in the second chamber 6 to flow freely throughout the entire casing.

[0052] The electrode assembly is installed in the first chamber 5, while the second chambers 6 on both sides store free electrolyte. When the electrode assembly is working, its consumption of electrolyte is replenished in a timely manner, effectively preventing localized electrolyte drying and ensuring the consistency and stability of the internal reaction of the battery, thereby significantly improving the battery's charge and discharge performance. Simultaneously, the through holes on the separator 4 ensure continuous and stable electrolyte flow between the first chamber 5 and the second chamber 6, maintaining the uniformity of electrolyte concentration inside the battery. When the battery heats up, the heat absorbed by the free electrolyte is dispersed to the casing through the through chambers and dissipated through the surface, effectively preventing overheating, reducing the risk of thermal runaway, precisely controlling temperature, and maintaining battery performance. Furthermore, the separators 4 on both sides of the electrode assembly effectively maintain the relative position of the electrode assembly, preventing displacement, shaking, or even damage due to external forces such as vibration and collision within the casing. The supporting effect of the separators 4 is particularly significant when the battery is used in complex vibration environments.

[0053] In other embodiments, the number and position of the partitions 4 can be adjusted according to actual needs. For example, a partition 4 parallel to the xz plane can be set inside the cylinder to divide the inner cavity of the cylinder into two chambers, which are respectively used as the first chamber 5 and the second chamber 6. Alternatively, four partitions 4 can be set inside the cylinder, two of which are parallel to the yz plane and the other two are parallel to the xz plane, dividing the inner cavity of the cylinder into five chambers, with the four outer chambers serving as the second chamber 6 and the middle chamber serving as the first chamber 5.

[0054] like Figure 2 As shown, this embodiment also has multiple protrusions 31 arranged in an array on the inner surface of the lower cover plate 3. The tops of the protrusions 31 are used to support the electrode assembly, and the gaps between the protrusions 31 serve as electrolyte flow channels. The aforementioned multiple protrusions 31 can be arranged in a rectangular array or a ring array, etc.; the regularly arranged multiple protrusions 31 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 31 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.

[0055] To reduce costs and battery weight, this embodiment uses a plastic casing. Plastic is also easy to process; for example, complex shapes can be quickly manufactured using injection molding. As in this embodiment, the lower cover 3, cylinder 2, and separator 4 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 lower cover 3 and 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. The upper cover 1 and cylinder 2 can be connected using a heat-sealing method. Figure 3 As shown, a stepped structure 11 can be provided along the edge of the upper cover plate 1 as a positioning structure for the open end of the cylinder 2. During assembly, this allows for a highly precise fit between the cylinder 2 and the upper cover plate 1, significantly improving assembly accuracy and efficiency while reducing the difficulty and error of manual operation. Subsequently, the open end of the cylinder 2 is sealed to the stepped structure 11 via heat fusion, a highly efficient and tight sealing method. During the heat fusion process, the plastic materials fuse together to form a seamless connection, effectively preventing external impurities and moisture from entering the battery.

[0056] It should be noted that the plastic material selected in this invention should have the following properties:

[0057] First, it must have sufficient strength to ensure the stability of the battery structure;

[0058] Second, it has chemical corrosion resistance and can resist the corrosion of electrolytes;

[0059] 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.

[0060] 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.

[0061] The plastic material used can be the same material used in existing plastic-cased single-cell batteries 8, or the plastic material disclosed in Chinese patents CN106543551A and CN106977894A.

[0062] In some other embodiments, a metal shell can also be used, with the partition 4 and the cylinder being separate parts, which are fixed to the inner cavity of the cylinder by welding or plugging.

[0063] Example 2

[0064] This embodiment is another type of single battery. Unlike embodiment 1, this embodiment has multiple stiffening plates 7 on the inner wall of at least one side wall of the cylinder, and the space between adjacent stiffening plates 7 is used as a second chamber 6.

[0065] The specific structure is as follows: Figure 4 As shown, in this embodiment, multiple ribs 7 are provided on the inner wall parallel to the yz plane. Each rib 7 extends along the z-direction, and the multiple ribs 7 are arranged along the y-direction. Based on the above ribs 7, firstly, multiple second chambers 6 can be constructed, and the ribs 7 extending along the z-direction can achieve rapid and uniform distribution of electrolyte in the height direction, ensuring that the electrode assembly can fully contact the electrolyte throughout the entire height range, avoiding reaction differences caused by uneven distribution of electrolyte in the height. The multiple ribs 7 arranged along the y-direction also allow the electrolyte to uniformly penetrate into the electrode assembly in the width direction, greatly improving the uniformity of the internal reaction of the battery and further optimizing the battery's charge and discharge performance. Secondly, it can enhance the strength of the cylindrical structure, thereby enhancing the strength of the shell structure, effectively dispersing external forces in various directions, resisting bending and torsional deformation, and preventing internal short circuits. Thirdly, the rib structure with a clear regularity in a specific direction makes mold design simpler, greatly simplifying the complexity of the mold, and making it easier to control the processing accuracy during production.

[0066] Preferably, in this embodiment, multiple stiffeners 7 are provided on both inner walls parallel to the yz plane, and the stiffeners 7 on the two inner walls are symmetrical to each other, thereby forming multiple symmetrical second chambers 6 on opposite side walls. The symmetrical arrangement of the second chambers 6 on opposite side walls can ensure that the electrolyte permeates into the electrode assembly uniformly from both sides during battery charging and discharging, greatly improving the uniformity of the internal reaction of the battery and further optimizing the battery charging and discharging performance.

[0067] In other embodiments, the number, position, and arrangement of the stiffeners 7 can be adjusted according to actual needs. For example, to further optimize the electrolyte distribution and improve the structural strength, multiple stiffeners 7 can be provided on all four inner walls of the cylinder, allowing the electrolyte to penetrate evenly into the electrode assembly from more directions, greatly improving the uniformity of electrolyte distribution, and enhancing the cylinder's ability to resist external forces in all directions. However, compared to this embodiment, its cylinder volume is larger.

[0068] Furthermore, the arrangement of the stiffening ribs 7 on the inner wall can also be adjusted. Besides the conventional parallel arrangement, the stiffening ribs 7 can also be arranged in a spiral or a staggered grid pattern. This arrangement creates a tight support network, ensuring smooth electrolyte flow while significantly improving the overall structural strength of the casing and effectively coping with complex external forces. By flexibly adjusting the number, position, and arrangement of the stiffening ribs 7, the battery casing can meet the diverse needs for battery performance and structural stability in different application scenarios.

[0069] Similar to Example 1, this example also uses a plastic shell. This allows for the injection molding process to form the lower cover plate 3, cylinder 2, and stiffening plate 7 in one piece, reducing production steps and shortening the production cycle.

[0070] Example 3

[0071] This embodiment is another type of single cell. Unlike Embodiments 1 and 2, this embodiment combines the separator 4 in Embodiment 1 and the stiffener 7 in Embodiment 2 to form a second chamber 6 on the inner wall of at least one side wall of the cylinder.

[0072] For details, please refer to [link / reference]. Figure 5 Similar to Embodiment 1, this embodiment has a partition 4 parallel to the yz plane inside the cylinder, which divides the inner cavity of the cylinder into a first chamber 5 and a second chamber 6. Figure 5Taking the addition of a partition 4 as an example, to ensure smooth flow of electrolyte between the first chamber 5 and the second chamber 6, multiple through holes are provided on the partition 4 to achieve interconnection between the two chambers, allowing the free electrolyte stored in the second chamber 6 to flow freely within the shell. Unlike Embodiment 1, this embodiment also provides multiple stiffening plates 7 in the second chamber 6. Each stiffening plate 7 extends along the z-direction, and the multiple stiffening plates 7 are arranged along the y-direction. The two sides of each stiffening plate 7 abut against the inner wall of the cylinder (parallel to the yz plane) and the partition 4, respectively.

[0073] In some other embodiments, similar to Embodiment 1, the number and position of the partitions 4 can be adjusted according to actual needs. Correspondingly, the number, position and arrangement of the stiffeners 7 can also be adjusted in the manner described in Embodiment 2.

[0074] Compared to Embodiment 1, the multiple reinforcing ribs 7 added to the second chamber 6 in this embodiment significantly enhance the support effect of the partition 4. Since each reinforcing rib 7 abuts against the inner wall of the cylinder (parallel to the yz plane) and the partition 4 on both sides, a stable support frame is formed. When the electrode assembly is subjected to vibration or external impact, the reinforcing ribs 7 can work in conjunction with the partition 4 to distribute the force across the entire shell structure, effectively reducing the risk of displacement of the electrode assembly under complex external force environments and improving the stability and reliability of the battery.

[0075] In addition, compared with Embodiment 1, this embodiment greatly improves the overall strength of the shell by adding multiple stiffening plates 7.

[0076] Compared to Embodiment 2, the partition 4 added in this embodiment defines a clear installation space for the electrode assembly, effectively preventing unnecessary shaking or displacement of the electrode assembly within the housing, and further improving the stability of the electrode assembly within the housing.

[0077] Example 4

[0078] Unlike the embodiments described above, this embodiment, in order to further reduce costs, requires that the strength of each individual battery casing meets certain requirements. However, this embodiment does not require the casing 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.

[0079] 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.

[0080] 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 traditional single-cell battery 8; the thickness of the plastic shell of a traditional single-cell battery 8 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 traditional single-cell battery 8 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.

[0081] Example 5

[0082] This embodiment is a battery pack, including a pressure-bearing housing 9 and 12 individual battery cells 8 as described in the above embodiment. In other embodiments, the number of individual battery cells 8 can be adjusted according to actual needs.

[0083] Its structure is as follows Figure 6 and Figure 7 As shown, the 12 individual battery cells 8 in the above embodiments are arranged inside the pressure-bearing housing 9. The pressure-bearing housing 9 is provided with an explosion vent. This explosion vent can also be referred to as an explosion vent section, explosion-proof vent, etc.

[0084] The strength of the pressure-bearing housing 9 needs to meet the strength requirements of the casing during thermal runaway, meaning that the pressure-bearing housing 9 needs to have good strength. This design not only effectively resists the high-pressure impact during thermal runaway with the reinforced outer casing, greatly improving the overall safety of the battery pack; especially when plastic material is used as the casing of the internal individual cells 8, the pressure-bearing housing 9 can form a robust thermal barrier. Even in the extreme case where the casing of the individual cell 8 melts, it can effectively isolate high-temperature flames and harmful gases, preventing the spread of thermal runaway and improving the safety of the battery pack after thermal runaway. In addition, when plastic material is used as the casing of the internal individual cells 8, an anti-seepage membrane 12 can be provided between each individual cell 8 and the pressure-bearing housing 9 to prevent the electrolyte inside each individual cell 8 from seeping out.

[0085] Compared to other materials, the metal pressure tank 9 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 personnel and surrounding equipment. In this embodiment, the pressure tank 9 does not directly contact the electrolyte, so an iron, steel, or stainless steel shell can be used. An iron shell offers advantages in strength and cost, making it a viable option in scenarios where cost is a primary concern and strength requirements are not particularly stringent. A steel shell provides relatively high strength, offering more reliable protection for the battery and is suitable for applications with high safety and structural strength requirements. A stainless steel shell not only possesses good strength properties but also excellent corrosion resistance, making it perform exceptionally well in battery applications that may face humid or corrosive environments. This effectively extends battery life and ensures stable operation in complex environments.

[0086] To optimize the heat dissipation performance of the battery pack, this embodiment may further include a heat exchange component 10 to exchange heat with the polarity terminals. As a crucial connection between 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 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.

[0087] The heat exchange component 10 is a heat transfer tube; each polarity terminal of the individual cell 8 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 of the individual cell 8. By using the heat transfer tube on the polarity terminal, the heat generated inside the battery is conducted to the heat transfer tube through the polarity terminal, and then the heat transfer tube dissipates the heat to achieve heat dissipation of the battery.

[0088] The heat exchange component 10 can also be a heat exchange device, which is disposed on top of each individual battery cell 8. 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, thus achieving heat exchange at the polar terminal. Compared to indirect heat exchange, this method has a shorter heat exchange path, and the heat exchange medium acts directly on the polar terminal, improving the utilization efficiency of the heat exchange medium and enhancing the battery's heat exchange efficiency.

Claims

1. A cylindrical body for a single-cell battery, characterized in that: It includes a first chamber and at least one second chamber; the first chamber serves as an electrode assembly receiving chamber for mounting the electrode assembly; the second chamber serves as an electrolyte storage chamber for storing free electrolyte; wherein the first chamber and the second chamber are connected.

2. The cylindrical body for a single battery according to claim 1, characterized in that: It includes a partition installed in the inner cavity of the cylinder, which divides the inner cavity of the cylinder into a first chamber and a second chamber. The partition has multiple hollow areas to allow the first chamber and the second chamber to communicate with each other.

3. The cylindrical body for a single battery according to claim 1, characterized in that: Multiple stiffening plates are provided on the inner wall of at least one side wall of the cylinder, and the space between adjacent stiffening plates is used as a second chamber.

4. The casing for a single-cell battery according to claim 3, characterized in that: Multiple stiffening ribs are symmetrically arranged on two parallel side walls of the cylinder; Define the length direction of the cylinder as the x-direction, the width direction as the y-direction, and the height direction as the z-direction; Both sidewalls are parallel to the yz plane; Each stiffener extends along the z-direction, and multiple stiffeners are arranged along the y-direction.

5. The cylindrical body for a single battery according to claim 1, characterized in that: It includes a partition installed in the inner cavity of the cylinder, which divides the inner cavity of the cylinder into a first chamber and a second chamber. The partition has multiple hollow areas to allow the first chamber and the second chamber to communicate with each other. In the second chamber, there are multiple stiffening plates that extend along the z-direction. The two sides of each stiffening plate abut against the inner wall of the cylinder and the partition, respectively.

6. A casing for a single battery cell, characterized in that: It is formed by an upper cover plate, a cylindrical body and a lower cover plate, wherein the cylindrical body is the single-cell battery cylindrical body as described in any one of claims 1 to 5; the upper cover plate, the cylindrical body and the lower cover plate are all made of plastic.

7. The housing for a single battery cell according to claim 6, characterized in that: The inner wall 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.

8. The housing for a single battery cell according to claim 7, characterized in that: The upper cover plate has a stepped structure along its edge. The stepped structure serves as a positioning structure for the open end of the cylinder and is sealed to the open end of the cylinder by heat fusion.

9. The housing for a single battery cell according to claim 6, 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.

10. A single-cell battery, characterized in that: Includes the casing for a single-cell battery as described in any one of claims 6 to 9.

11. A battery pack, characterized in that: It includes a pressure-bearing housing and n individual batteries as described in claim 10, where n is an integer greater than 1; n individual cells are arranged inside a pressure tank; the strength of the pressure tank meets the strength requirements of the casing during the thermal runaway stage, and the pressure tank is equipped with a vent.

12. The battery pack according to claim 11, characterized in that: It also includes heat exchange components that exchange heat with the polarity terminals.

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