Single battery assembly and battery module

Abstract

The utility model belongs to the field of batteries, and particularly relates to a single battery assembly and a battery module. The problems that an existing plastic shell battery is poor in safety during thermal runaway, harmful substances are easily released and the like are solved. The single battery assembly comprises a single battery and a pressure-bearing shell; the single batteries are plastic shell batteries; the single batteries are mounted in the pressure-bearing shell, and polarity terminals of the single batteries extend out of the pressure-bearing shell; wherein the strength of the pressure-bearing shell meets the requirement on the strength of the shell in a thermal runaway stage. According to the utility model, the double-layer shell is adopted, and the pressure-bearing shell has better strength, so that a thermal runaway stage is ensured, the structural integrity is kept, a firm barrier can be formed, and high-temperature substances, flames, possibly leaked electrolyte and the like in the battery are prevented from being directly exposed in an external environment, so that the risks of fire and explosion are greatly reduced, and the service life of the battery is prolonged. And the safety of the whole single battery assembly under extreme conditions is improved.

Description

Technical Field

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

[0002] In lithium-ion battery applications, the performance of the battery casing is crucial to the overall safety and stability of the battery. Currently, commonly used plastic-cased batteries exhibit numerous problems when facing thermal runaway. When thermal runaway occurs, the insufficient mechanical strength and temperature resistance of the plastic casing make it prone to deformation, cracking, and even melting. This can not only cause direct contact between the positive and negative electrodes inside the battery, leading to a short circuit and generating a large amount of heat that exacerbates thermal runaway, but may even cause dangerous situations such as fire and explosion. Furthermore, the decomposition of the plastic casing at high temperatures releases harmful substances, and the electrolyte inside the battery may also leak, further increasing the release of harmful substances and posing a serious threat to the surrounding environment and personnel safety. Summary of the Invention

[0003] The purpose of this invention is to provide a single-cell battery assembly and battery module that overcomes the problems of poor safety and easy release of harmful substances in existing plastic-cased batteries during thermal runaway.

[0004] The first aspect of this utility model provides a single-cell battery assembly, which is characterized in that it includes a single-cell battery and a pressure-bearing housing.

[0005] The individual battery is a plastic-cased battery;

[0006] The individual battery is installed inside the pressure-bearing housing, and the polarity terminal of the individual battery extends out of the pressure-bearing housing and is sealed to the pressure-bearing housing;

[0007] The strength of the pressure-bearing shell meets the strength requirements for the shell during the thermal runaway stage.

[0008] This invention employs a double-layer shell, specifically a pressure-bearing shell layered over the existing plastic shell of a plastic-cased battery. The strength of this pressure-bearing shell must meet the strength requirements of the shell during thermal runaway; that is, the pressure-bearing shell possesses superior strength to ensure that even if the internal plastic shell softens, deforms, cracks, or even melts during thermal runaway, the pressure-bearing shell can maintain structural integrity due to its high strength, effectively constraining the internal battery components and preventing short circuits caused by direct contact between the positive and negative electrodes. Simultaneously, the pressure-bearing shell also forms a robust barrier, preventing high-temperature substances, flames, and potentially leaking electrolyte from being directly exposed to the external environment, thereby significantly reducing the risk of fire and explosion and improving the safety of the entire single-cell battery assembly under extreme conditions.

[0009] Furthermore, the pressure-bearing casing is a metal casing. Metal casings typically possess high mechanical strength, enabling them to withstand significant pressure without easily deforming or being damaged. Simultaneously, metals exhibit excellent thermal conductivity, allowing them to rapidly dissipate heat generated inside the battery during thermal runaway, preventing excessive heat accumulation within the battery and helping to reduce the peak temperature inside, thus further mitigating the severity of thermal runaway.

[0010] Furthermore, the metal casing can be made of iron, steel, or stainless steel. By offering a variety of metal casing materials, it is possible to better adapt to the usage requirements of lithium-ion batteries in different fields and under different operating conditions, enabling a more optimized balance in terms of safety, performance, and cost for individual battery cells, battery modules, and other aspects, thus providing strong support for the wider application of lithium-ion battery technology.

[0011] Furthermore, the polar terminals of the individual cells are provided with through slots or through holes for mounting heat transfer tubes.

[0012] Since the individual battery cells have plastic casings, their heat dissipation performance is poor. This invention addresses this by improving heat dissipation by addressing the heat concentration at the battery's polar terminals. When heat is generated inside the battery, heat dissipation through the polar terminals provides a relatively direct heat conduction path. Heat can be rapidly conducted from inside the battery to the polar terminals, and then dissipated from the terminals to the external environment.

[0013] Specifically, this utility model provides through slots or through holes on the polar terminals for installing heat transfer tubes. After constructing a battery module based on this type of battery, the heat generated inside the battery is conducted to the heat transfer tubes through the polar terminals using the heat transfer tubes on the polar terminals, and then the heat transfer tubes dissipate the heat to achieve heat dissipation of the battery.

[0014] The design of through slots or holes allows for a larger contact area between the heat transfer tube and the polarity terminal. Compared to planar contact, this embedded contact method enables more efficient heat transfer between the heat transfer tube and the polarity terminal, improving heat exchange efficiency. Furthermore, the shape of the through slots or holes provides a certain degree of locking and fixing for the heat transfer tube, preventing displacement or loosening during use. Especially in vibrating or shaking operating environments, this fixing method ensures that the heat transfer tube and the polarity terminal maintain good contact at all times, guaranteeing the stability of heat exchange.

[0015] Furthermore, each polarity terminal is provided with a functional structure, which is used to increase the heat exchange area of ​​that part of the polarity terminal.

[0016] Furthermore, an impermeable membrane is provided between the individual battery cell and the pressure-bearing casing to prevent the electrolyte inside the individual battery cell from seeping outward.

[0017] The second aspect of this utility model provides a battery module, which is characterized in that it includes n of the above-mentioned single battery components, where n is an integer greater than 1.

[0018] Furthermore, the battery module also includes a heat exchange component that exchanges heat with the polarity terminals.

[0019] As a crucial component connecting the battery's internal structure to the external environment, the polarity terminals allow current to flow in and out of the battery during charging and discharging. When heat is generated inside the battery, the polarity terminals provide a relatively direct heat conduction path. Heat can be rapidly conducted from inside the battery to the polarity terminals, and then dissipated into the external environment from there.

[0020] 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.

[0021] Furthermore, the heat exchange component is a heat transfer tube; the heat transfer tube is fixed in the through slot or through hole of the polarity terminal of each individual battery module. By utilizing 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.

[0022] Furthermore, the heat exchange component is a heat exchange device, which is disposed on the top of each individual battery module; the polar terminal penetrates the heat exchange device, and at least a part of the structure of the polar terminal is located in the inner cavity of the heat exchange device and is in direct contact with the heat exchange medium; another part of the structure of the polar terminal is located outside the heat exchange device and serves as an electrical connection part; the side wall of the polar terminal is sealed with the heat exchange device.

[0023] By adopting a direct heat exchange method, part of the polar terminal structure is placed directly inside the heat exchange medium flow cavity (the inner cavity of the heat exchange device), so that the polar terminal is in direct contact with the heat exchange medium, thereby realizing heat exchange of the polar terminal. Compared with the indirect heat exchange method, it has a shorter heat exchange path. The heat exchange medium acts directly on the polar terminal, improving the utilization efficiency of the heat exchange medium and improving the heat exchange efficiency of the battery.

[0024] Furthermore, the functional structure of the polar terminal is located inside the heat exchanger, which can further improve the heat exchange effect.

[0025] The beneficial effects of this utility model are:

[0026] 1. Enhance security;

[0027] By adding a pressure-bearing casing that meets specific strength requirements, the possibility of fire, explosion, and other dangerous situations caused by thermal runaway of individual plastic-cased batteries is greatly reduced. In the event of thermal runaway, the pressure-bearing casing can withstand internal pressure changes and high temperatures, preventing internal short circuits and further deterioration of thermal runaway, thus providing a more reliable guarantee for battery safety during use.

[0028] 2. Reduce the risk of releasing harmful substances;

[0029] Because the pressure-bearing casing effectively isolates high-temperature flames and harmful gases, preventing the spread of thermal runaway, it also reduces the release of harmful substances from the plastic casing due to high-temperature decomposition. Simultaneously, it also helps to prevent leakage of the battery's internal electrolyte, further reducing the harm of hazardous substances to the environment and personnel, and effectively controlling the impact of the battery on the surrounding environment in the event of thermal runaway. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of a single battery module in Example 1;

[0031] Figure 2 This is a schematic diagram of the exploded structure of a single battery module in Example 1;

[0032] Figure 3 This is a schematic diagram of the structure of a single battery module in Example 2;

[0033] Figure 4 This is a schematic diagram of the battery module structure in Example 3;

[0034] Figure 5 This is an exploded view of the battery module in Example 3;

[0035] Figure 6 This is a schematic diagram of the battery module structure in Example 4;

[0036] Figure 7 This is a schematic diagram of the heat exchange tubes in Example 4;

[0037] Figure 8 This is a cross-sectional view of the heat exchanger tubes in Example 4;

[0038] Figure 9 This is a schematic diagram of the first exploded structure of the battery module in Example 5;

[0039] Figure 10 This is a schematic diagram of the second exploded structure of the battery module in Example 5;

[0040] Figure 11 This is a schematic diagram of the heat exchange sleeve in Example 5;

[0041] Figure 12This is a schematic diagram of the structure of another heat exchange sleeve in Example 5;

[0042] The attached figures are labeled as follows:

[0043] 1. Single cell assembly; 2. Single cell; 21. Polar terminal; 224. Through slot; 225. Annular groove; 3. Pressure-bearing shell; 4. Heat transfer tube; 5. Heat exchange fitting; 51. Through hole; 512. Bottom port; 513. Top port; 6. Heat exchange sleeve; 311. Hollow component; 312. Annular sealing plate; 313. First through hole; 314. Liquid inlet pipe; 315. Liquid outlet pipe. Detailed Implementation

[0044] 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.

[0045] 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.

[0046] In the description of this utility model, it should be noted that the terms "top" and "bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this utility model.

[0047] Example 1

[0048] like Figure 1 and Figure 2 As shown, the single-cell battery assembly 1 in this embodiment mainly consists of two parts: a single-cell battery 2 and a pressure-bearing housing 3.

[0049] Among them, cell 2 is a plastic-cased battery, which is consistent with the existing common plastic-cased battery type.

[0050] The individual battery 2 is installed inside the pressure-bearing housing 3, and the polar terminal 21 of the individual battery 2 extends out of the pressure-bearing housing 3 and is sealed with the pressure-bearing housing 3 to ensure that the battery can be electrically connected normally.

[0051] In addition, a waterproof membrane can be installed between the individual battery cell and the pressure-bearing casing to prevent the electrolyte inside the individual battery cell from seeping out.

[0052] The strength of the pressure-bearing casing 3 must meet the strength requirements of the casing during thermal runaway. Specifically, it must possess good strength performance so that even if the internal plastic shell softens, deforms, cracks, or even melts during thermal runaway, the pressure-bearing casing 3 can still act as a robust barrier, effectively confining the internal components of the battery. Simultaneously, it can effectively isolate high-temperature flames and harmful gases, preventing further spread of thermal runaway, thereby improving the safety of the entire single-cell battery assembly 1 under extreme conditions. At the same time, it also plays a role in preventing leakage of electrolyte inside the battery, further reducing the harm of hazardous substances to the environment and personnel, and effectively controlling the impact of the battery on the surrounding environment in the event of thermal runaway.

[0053] Compared to other materials, the metal pressure-bearing casing 3 is more reliable in emergency situations such as thermal runaway. It can withstand greater impact and destructive forces, reducing the likelihood of accidents and protecting the safety of personnel and surrounding equipment. Since the pressure-bearing casing 3 in this embodiment does not directly contact the electrolyte, an iron, steel, or stainless steel casing can be used. An iron casing 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 casing 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 casing not only possesses good strength properties but also excellent corrosion resistance, making it perform well in battery applications that may face humid or corrosive environments, effectively extending battery life and ensuring stable operation in complex environments. In other embodiments, an aluminum casing can also be used. Aluminum casings are lightweight, reducing the overall weight of the battery, making them a better choice for applications with strict weight requirements.

[0054] By offering a variety of metal casing options, this invention can better adapt to the usage requirements of lithium-ion batteries in different fields and under different working conditions, enabling the single cell 2 and battery module to achieve a more optimized balance in terms of safety, performance and cost.

[0055] Example 2

[0056] Based on Example 1, this embodiment provides through slots 224 or through holes for installing heat transfer tubes 4 on the two polar terminals 21.

[0057] For details, please refer to [link / reference]. Figure 3As shown in the figure, the polar terminal 21 in this embodiment is a cylindrical body, including a second end face, a first end face, and a side face (the second end face and the first end face are parallel to each other). The second end face is provided with an electrical connection area for connection with an external electrical connector, and the first end face is used for electrical connection with the electrode assembly inside the housing. A through groove 224 is provided on the side face (i.e., the opening of the through groove 224 is located on the side face), which serves as a mounting part for the heat transfer tube 4 to be installed.

[0058] In some other embodiments, a through hole may be provided on the side, that is, the opening of the through hole is located on the side.

[0059] In some other embodiments, the through groove 224 may also be formed on the second end face, that is, the opening of the through groove 224 is located on the second end face.

[0060] By creating through slots 224 and through holes on the side, compared to creating through slots 224 on the second end face, the heat transfer tube 4 has a larger contact area with the inner wall of the through slot 224, resulting in higher heat exchange efficiency. Furthermore, when the through slots 224 and through holes are located on the side, the entire area of ​​the second end face can be used as an electrical connection area. Two through slots 224 or through holes can also be provided on the side of the polarity terminal 21 simultaneously to increase the number of heat transfer tubes 4 and further improve heat exchange efficiency.

[0061] Furthermore, the through-slot 224 structure makes the heat transfer tube 4 easier to install compared to the through-hole structure. To further improve the ease of installation of the heat transfer tube 4, such as... Figure 3 As shown, in this embodiment, the openings of the through slots 224 on the two polarity terminals 21 face the same direction. This unidirectional orientation allows the heat transfer tube 4 to be installed along one direction, eliminating the need for complex adjustments and alignments by the operator in different directions. This significantly improves installation efficiency.

[0062] The cross-section of the through-slot 224 is C-shaped or U-shaped. The opening width of the C-shaped through-slot 224 is smaller than the widest part of the through-slot 224. This design is conducive to the interference fit of the heat transfer tube 4 in the through-slot 224. The arc formed by the two ends of the C-shaped through-slot 224 has natural tension, which is conducive to the tight fit of the heat transfer tube 4 in the through-slot 224. The cross-section of the U-shaped through-slot 224 is rectangular at the opening and semi-circular near the bottom of the slot. The size of the opening is slightly smaller than the widest part of the through-slot 224 and also slightly smaller than the outer diameter of the heat transfer tube 4. This design is also conducive to the interference fit of the heat transfer tube 4 in the through-slot 224 and to fixing the heat transfer tube 4 in the through-slot 224. The interference fit is mainly in the bottom area of ​​the slot with a semi-circular cross-section.

[0063] The horizontal cross-section of the polarity terminal 21 can be circular, rectangular, or racetrack-shaped. Different shapes of polarity terminals 21 can be selected according to different battery models, or other different shapes. These will not be listed exhaustively in this embodiment.

[0064] In this embodiment, the first end face of the polarity terminal 21 is close to the electrode assembly. Therefore, the first end face is closer to the internal electrode assembly of the battery, and the heat transfer pipe 4 should be positioned as close as possible to the first end face. This arrangement allows the heat transfer pipe 4 to be as close as possible to the inside of the battery for heat transfer.

[0065] Example 3

[0066] This embodiment is a battery module, which includes multiple single battery components 1 as described in the above embodiments.

[0067] Figure 4 Taking the 12 individual battery modules 1 in Embodiment 2 as an example, in other embodiments, the number of individual battery modules 1 can be adjusted according to actual needs. As can be seen from the figure, this embodiment also includes a heat transfer pipe 4. The heat generated inside the battery module can be conducted to the heat transfer pipe 4 through the polarity terminal 21, and then the heat transfer pipe 4 dissipates the heat, thereby achieving heat dissipation of the battery module.

[0068] In this embodiment, the heat transfer tube 4 is U-shaped and includes a first tube, a second tube, and a connecting tube. The first tube is fixed in the through groove 224 of the polar terminal 21 on one side of each individual battery assembly 1 in the battery module. The second tube is fixed in the through groove 224 of the polar terminal 21 on the other side of each individual battery assembly 1 in the battery module. The two ends of the connecting tube are respectively connected to the ports of the first tube and the second tube on the same side.

[0069] like Figure 5 As shown, when installing heat transfer tube 4, the first tube, the second tube, and the connecting tube can be pre-assembled into one unit. Then, the first tube and the second tube are inserted into the corresponding through slot 224 in the direction shown by the arrow in the figure. The installation process is simple and convenient, which improves the installation efficiency.

[0070] Example 4

[0071] This embodiment is another type of battery module. Unlike embodiment 3, it uses a different heat exchange component to exchange heat on the polar terminal 21.

[0072] from Figure 6As can be seen from the diagram, the heat exchange component in this embodiment includes two heat exchange tubes 5. The two heat exchange tubes 5 are respectively disposed on the polarity terminals 21 on different sides of the battery module. In order to improve the safety performance of the battery module, the heat exchange tubes 5 should not be energized. In this embodiment, heat exchange tubes 5 made of insulating material can be selected. In some other embodiments, the walls of the non-insulated heat exchange tubes 5 can be insulated, such as by spraying insulating paint or wrapping with insulating film. An insulating sealing gasket can also be added between the polarity terminal 21 and the heat exchange tubes 5 to achieve the above purpose.

[0073] The structure of heat exchanger tube 5 is as follows Figure 7 and Figure 8 As shown in the figure, the heat exchange tube 5 in this embodiment has 12 through holes 51. The 12 through holes 51 are arranged along the x-direction and correspond one-to-one with the polarity terminals 21 of each individual battery module 1. In some other embodiments, the number of through holes 51 can be adjusted according to the number of individual battery modules 1 in the battery module, and the arrangement of the through holes 51 can be adjusted according to the arrangement of the individual battery modules 1.

[0074] The aforementioned through hole 51 is a through hole 51 that penetrates the top plate and bottom plate of the heat exchange tube 5 and communicates with the inner cavity of the heat exchange tube 5. In this embodiment, after the heat exchange tube 5 is fixed to the top of the single battery assembly 1, the extension direction of the through hole 51 is consistent with the height direction (i.e., the z direction) of the single battery assembly 1. Therefore, it can be considered that the through hole 51 extends along the z direction.

[0075] In addition, when the heat exchange tube 5 is fixed on the top of the single cell assembly 1, the electrical connection part of the polar terminal 21 of each single cell assembly 1 passes through the bottom port 512 of the corresponding through hole 51 and extends out from the top port 513, and the polar terminal 21 is sealed with the hole wall of the through hole 51. The top port 513 here is the port near the electrical connection part of the polar terminal 21.

[0076] from Figure 6 As can be seen from the diagram, in this embodiment, the two heat exchange tubes 5 are respectively sleeved on the polarity terminals 21 on different sides of the battery module based on the through holes 51, and the two heat exchange tubes 5 are connected in series through connecting pipes. In some other embodiments, the two heat exchange tubes 5 can also be connected in parallel.

[0077] In addition, this embodiment can also provide a functional structure on the polarity terminal 21 to increase the heat exchange area of ​​that part of the polarity terminal 21.

[0078] For details, please refer to [link / reference]. Figure 1In this embodiment, at least two annular grooves 225 are formed on the sidewall of the polarity terminal 21. The two annular grooves 225 are arranged along the height direction of the polarity terminal 21, and each annular groove 225 extends circumferentially along the sidewall of the polarity terminal 21. The heat exchange area of ​​this part of the polarity terminal 21 can be increased by the two annular grooves 225. Placing the part with the functional structure in the heat exchange medium flow cavity can further improve the heat exchange effect.

[0079] In some other embodiments, the number of annular grooves 225, as well as the dimensions such as groove width and groove depth, can be adjusted as needed, specifically without affecting the conductivity of the polarity terminal 21.

[0080] In other embodiments, other structures can be processed on the polarity terminal 21 to increase the heat exchange area of ​​the polarity terminal 21. Such functional structures may include dot-shaped pits or protrusions on the sidewall of the polarity terminal 21, and may also include through holes on the polarity terminal 21 (heat dissipation teeth can be added along its axial direction in the through hole to further increase the heat exchange area in the through hole). Compared with the above functional structures, the annular groove 225 structure in this embodiment is easier to process and has a lower processing cost.

[0081] This embodiment adopts a direct heat exchange method, in which part of the structure of the polar terminal 21 is placed directly in the inner cavity of the heat exchange tube 5, so that the polar terminal 21 is in direct contact with the heat exchange medium, thereby realizing heat exchange of the polar terminal 21. Compared with the indirect heat exchange method (the heat exchange method of embodiment 3), it has a shorter heat exchange path. The heat exchange medium acts directly on the polar terminal 21, improving the utilization efficiency of the heat exchange medium and improving the heat exchange efficiency of the battery.

[0082] Example 5

[0083] This embodiment is another type of battery module. Unlike embodiment 3, it uses a different heat exchange component to exchange heat on the polar terminal 21.

[0084] Combination Figure 9 and Figure 10 As can be seen, the heat exchange component in this embodiment includes 24 heat exchange sleeves 6, which are respectively set around the 24 polar terminals 21.

[0085] The structure of heat exchange sleeve 6 is as follows Figure 11 As shown, it includes a hollow component 311 and an annular sealing plate 312; two first through holes 313 are opened on the side wall of the hollow component 311 to penetrate its inner cavity, which serve as liquid inlet and liquid outlet respectively; the annular sealing plate 312 is coaxial with the hollow component 311 and is sealed and fixed at the top of the hollow component 311.

[0086] Combination Figure 9As can be seen, the heat exchange sleeve 6 is sleeved around the polar terminal 21, forming an annular cavity between it and the side wall of the polar terminal 21 (which may have an annular groove 225). This annular cavity serves as a flow cavity for the heat exchange medium. The bottom end of the hollow component 311 is sealed and fixed to the polar terminal 21. The inner ring surface of the annular sealing plate 312 is sealed and fixed to the side wall of the polar terminal 21. At the same time, part of the structure of the polar terminal 21 extends out of the inner hole of the annular sealing plate 312, serving as the electrical connection part of the polar terminal 21.

[0087] This utility model does not specifically limit the cross-sectional shape of the hollow component 311. Generally, the cross-sectional shape of the hollow component 311 is adapted to the cross-sectional shape of the polar terminal 21. For example, when the cross-section of the polar terminal 21 is circular, the cross-section of the corresponding hollow component 311 is annular; when the cross-section of the polar terminal 21 is square, the cross-section of the corresponding hollow component 311 is square annular.

[0088] In this embodiment, the hollow component 311 and the annular sealing plate 312 are an integral part. In some other embodiments, the hollow component 311 and the annular sealing plate 312 can be separate parts, but the processing is more complicated than in this embodiment.

[0089] In this embodiment, the heat exchange sleeve 6 is made of rubber, which has a certain degree of elastic deformation. The bottom end of the hollow component 311 and the polar terminal 21 are tightly fitted together to achieve a sealed fixation. To improve the sealing reliability, insulating sealant can also be used for bonding. The inner ring surface of the annular sealing plate 312 and the side wall of the polar terminal 21 are sealed by a tight fit. In some other embodiments, an annular sealing ring can be added between the inner ring surface of the annular sealing plate 312 and the side wall of the polar terminal 21 to further improve the sealing performance.

[0090] In some other embodiments, the bottom end of the heat exchange sleeve 6 can also be sealed and fixed to the top cover of the single battery assembly 1 to ensure a seal between the hollow component 311 and the side wall of the polar terminal 21.

[0091] like Figure 9 As shown, in this embodiment, the heat exchange sleeves 6 of each individual battery module 1 located on the same side are connected to form two heat exchange channels on the top of the 12 individual battery modules 1. The two heat exchange channels can be connected in parallel or in series, and heat exchange is achieved based on the two heat exchange channels.

[0092] In this embodiment, as Figure 12 As shown, the heat exchange sleeve 6 may also include an inlet pipe 314 and an outlet pipe 315; the inlet pipe 314 and the outlet pipe 315 are both fixed on the side wall of the hollow component 311 and are respectively connected to the inlet and the outlet.

[0093] The hollow component 311, the annular sealing plate 312, the liquid inlet pipe 314 and the liquid outlet pipe 315 are integrated into one piece, and all of them are made of insulating material, preferably an insulating material with a certain degree of elastic deformation.

[0094] It should be noted that the inlet pipe 314 of one heat exchanger 6 and the outlet pipe 315 of the other heat exchanger 6 can be connected to each other to achieve communication between the two adjacent heat exchanger 6. Alternatively, a connecting pipe section can be used to connect the inlet pipe 314 of one heat exchanger 6 and the outlet pipe 315 of the other heat exchanger 6 to achieve communication between the two adjacent heat exchanger 6.

[0095] This embodiment can adopt the following two installation methods to fix the heat exchange component to each individual battery module 1:

[0096] Installation Method 1:

[0097] like Figure 9 As shown, each heat exchange sleeve 6 is fitted onto the corresponding polarity terminal 21 one by one. During the fitting process, adjacent heat exchange sleeves 6 are connected, and the top and bottom open ends of the heat exchange sleeve 6 are sealed to the side wall of the polarity terminal 21; finally, two heat exchange channels are formed.

[0098] Installation Method Two:

[0099] like Figure 10 As shown, firstly, the heat exchange sleeves 6 are connected to form two heat exchange channels. Then, each heat exchange channel is installed as a whole on top of the 12 individual battery modules 1. During the installation process, each heat exchange sleeve 6 of each heat exchange channel is fitted onto the corresponding polarity terminal 21 to complete the sealing between the open top end and the open bottom end of the heat exchange sleeve 6 and the side wall of the polarity terminal 21; finally, two heat exchange channels are formed.

[0100] By adopting a direct heat exchange method, part of the structure of the polar terminal 21 is placed directly in the inner cavity of the heat exchange sleeve 6, so that the polar terminal 21 is in direct contact with the heat exchange medium, thereby realizing heat exchange of the polar terminal 21. Compared with the indirect heat exchange method (the heat exchange method of Example 4), it has a shorter heat exchange path. The heat exchange medium acts directly on the polar terminal 21, improving the utilization efficiency of the heat exchange medium and improving the heat exchange efficiency of the battery.

Claims

1. A single-cell battery assembly, characterized in that: Includes individual battery cells and pressure-bearing casing; The individual battery is a plastic-cased battery; The individual battery is installed inside the pressure-bearing housing, and the polarity terminal of the individual battery extends out of the pressure-bearing housing and is sealed to the pressure-bearing housing; The strength of the pressure-bearing shell meets the strength requirements for the shell during the thermal runaway stage.

2. The single-cell battery assembly according to claim 1, characterized in that: The pressure-bearing shell is a metal shell.

3. The single-cell battery assembly according to claim 2, characterized in that: The metal casing is made of iron, steel, or stainless steel.

4. The single-cell battery assembly according to any one of claims 1 to 3, characterized in that: The polarity terminals of a single cell are provided with slots or holes for mounting heat transfer tubes.

5. The single-cell battery assembly according to any one of claims 1 to 3, characterized in that: Each individual battery cell has a functional structure on its polarity terminal, which is used to increase the heat exchange area of ​​that part of the polarity terminal.

6. The single-cell battery according to any one of claims 1 to 3, characterized in that: An impermeable membrane is provided between the individual battery cell and the pressure-bearing casing to prevent the electrolyte inside the individual battery cell from seeping out.

7. A battery module, characterized in that: It includes n single-cell battery modules as described in any one of claims 1 to 6, where n is an integer greater than 1.

8. The battery module according to claim 7, characterized in that: It also includes heat exchange components that exchange heat with the polarity terminals.

9. The battery module according to claim 8, characterized in that: The heat exchange component is a heat transfer tube; the heat transfer tube is fixed in the through slot or through hole of the polarity terminal of each individual battery module.

10. The battery module according to claim 8, characterized in that: The heat exchange component is a heat exchange device, which is located on top of each individual battery module; the polar terminal penetrates the heat exchange device, and at least a part of the structure of the polar terminal is located inside the heat exchange device and is in direct contact with the heat exchange medium; another part of the structure of the polar terminal is located outside the heat exchange device and serves as an electrical connection part; the side wall of the polar terminal is sealed with the heat exchange device.

11. The battery module according to claim 10, characterized in that: The part of the polarity terminal with a functional structure is located inside the heat exchanger.

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