Single battery assembly and battery module

Abstract

The invention belongs to the field of batteries, and particularly relates to a single battery assembly and a battery module. The problem of potential safety hazards caused by heating of the battery module is solved. The single battery assembly comprises a single battery and a heat exchange device; the heat exchange device is positioned at the top of the single battery; an inner cavity of the heat exchange device serves as a heat exchange medium flowing cavity; a polar terminal of the single battery penetrates through the heat exchange device, and at least part of the structure of the polar terminal is located in the heat exchange medium flowing cavity and is in direct contact with the heat exchange medium; and the other part of the structure of the polar terminal is positioned outside the heat exchange device and is used as an electric connection part. The battery module comprises the single battery assembly; the heat exchange devices of the adjacent single battery assemblies are communicated with each other, and a heat exchange channel is formed at the top of the battery module, so that heat exchange of the battery module is realized. The partial structure of the polar terminal is directly arranged in the heat exchange medium flowing cavity, so that the polar terminal is in direct contact with the heat exchange medium for heat exchange, a short heat exchange path is provided, and the heat exchange efficiency of the battery is improved.

Description

Technical Field

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

[0002] Battery modules generate heat during operation. Failure to dissipate heat in a timely manner can affect the performance and lifespan of the battery module, and may even lead to thermal runaway and safety hazards. Therefore, effective thermal management of battery modules is a key issue in ensuring their safe and stable operation. Summary of the Invention

[0003] The purpose of this invention is to provide a single-cell battery assembly and battery module to overcome the safety hazards caused by overheating of the battery module.

[0004] The first aspect of the present invention provides a single-cell battery assembly, including a single-cell battery and a heat exchange device; the heat exchange device is located on top of the single-cell battery, and the inner cavity of the heat exchange device serves as a heat exchange medium flow cavity; the polar terminal of the single-cell battery passes through the heat exchange device, and at least a portion of the structure of the polar terminal is located inside the heat exchange medium flow cavity and is in direct contact with the heat exchange medium; another portion of the structure of the polar terminal is located outside the heat exchange device and serves as an electrical connection portion.

[0005] This invention incorporates a heat exchange device on the top of a single battery cell. After constructing a battery module based on these single-cell battery components, the heat exchange devices of each individual battery cell can be connected to form a heat exchange channel on the top of the battery module for heat exchange. This heat exchange device primarily heats the polar terminals of the single battery cells where heat is concentrated. Furthermore, it employs a direct heat exchange method, placing a portion of the polar terminal structure directly within the heat exchange medium flow cavity, 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 compared to indirect heat exchange methods. The heat exchange medium directly acts on the polar terminal, improving the utilization efficiency of the heat exchange medium and thus enhancing the overall heat exchange efficiency of the battery.

[0006] The heat exchange device described above can adopt different structural forms, and the present invention provides at least the following four:

[0007] The first type of heat exchange device:

[0008] The heat exchange device includes two first heat exchange tubes, each of which includes a first tube body. The first tube body has a first channel and a second channel. The inner cavity of the first channel serves as a flow cavity for the heat exchange medium. The second channel is perpendicular to the first channel and communicates with the first channel.

[0009] Each single cell has two polarized terminals corresponding to two first heat exchange tubes; at least a portion of the structure of each polarized terminal is inserted into the first channel of the corresponding first heat exchange tube through the second channel and is in direct contact with the heat exchange medium in the first channel, while the other portion of the structure extends out of the second channel as an electrical connection part; the two ports of the second channel are sealed to the polarized terminals.

[0010] The second type of heat exchange device:

[0011] The heat exchange device includes a second heat exchange tube, which includes a second tube body. The second tube body has a first channel and two second channels. The inner cavity of the first channel serves as a flow cavity for the heat exchange medium. The second channel is perpendicular to the first channel and communicates with the first channel. The two polar terminals of the single cell correspond one-to-one with the two second channels. At least a portion of the structure of each polar terminal is inserted into the first channel of the second heat exchange tube through the corresponding second channel, and the other portion of the structure extends out of the second channel as an electrical connection part.

[0012] The two ports of the second channel are sealed with the polarity terminals.

[0013] In both of the above heat exchanger structures, at least a portion of the polar terminal structure can be located within the heat exchange medium flow chamber, directly contacting the heat exchange medium to achieve effective heat dissipation.

[0014] Furthermore, two annular grooves can be formed along the circumference of the polarity terminal, and the two annular grooves are arranged along the z-direction; each of the two annular grooves is embedded with an O-ring seal, and the outer rings of the two O-ring seals are pressed against the two ports of the second channel respectively, so as to achieve a seal between the two ports of the second channel and the polarity terminal.

[0015] The third type of heat exchange device:

[0016] The heat exchange device includes two third heat exchange tubes, each corresponding to one of the two polarity terminals of a single cell.

[0017] The third heat exchange tube is a half tube with an clearance hole on its wall; the third heat exchange tube is fastened and sealed to the top cover of the single cell; the space between the third heat exchange tube and the top cover of the single cell serves as a flow chamber for the heat exchange medium.

[0018] At least a portion of the polar terminal of a single cell is located within the heat exchange medium flow chamber, while another portion extends out of the clearance hole corresponding to the third heat exchange tube, serving as an electrical connection portion.

[0019] The polarity terminal is sealed to the corresponding clearance hole.

[0020] The fourth type of heat exchange device:

[0021] The heat exchange device includes a fourth heat exchange tube, which is a half tube. Two clearance holes are opened on the tube wall of the half tube, and the two clearance holes correspond one-to-one with the two polarity terminals of the single cell.

[0022] The fourth heat exchange tube is fastened and sealed to the upper cover plate of the single cell; the space formed between the fourth heat exchange tube and the upper cover plate of the single cell serves as a flow cavity for the heat exchange medium.

[0023] At least a portion of the structure of the two polar terminals of a single cell is located inside the heat exchange medium flow chamber, and the other portion of the structure extends out of the corresponding clearance hole as an electrical connection part;

[0024] The polarity terminal is sealed to the corresponding clearance hole.

[0025] In the third and fourth heat exchange devices mentioned above, at least part of the structure of the polar terminal and at least part of the structure of the top cover plate of the single cell are in direct contact with the heat exchange medium, resulting in better heat exchange performance.

[0026] Furthermore, the heat exchange device is made of electrically insulating materials, which can minimize the occurrence of short circuits.

[0027] Furthermore, an opening mechanism can be provided on the bottom cover of the individual battery cell. When constructing a large-capacity battery based on this type of individual battery cell, the electrolyte of each individual battery cell can be connected by opening the opening mechanism, thereby achieving the effect of electrolyte sharing.

[0028] Furthermore, connecting pipe sections can be connected to the inlet and / or outlet ends of the heat exchanger. These connecting pipe sections allow for the connection of heat exchangers between adjacent individual cells.

[0029] A second aspect of the present invention provides a battery module, including the above-mentioned single-cell battery assembly; the heat exchange devices of adjacent single-cell battery assemblies are interconnected, forming a heat exchange channel at the top of the battery module to realize heat exchange of the battery module.

[0030] Furthermore, the first heat exchange pipes of adjacent single-cell battery modules located on the same side are interconnected through connecting pipe sections.

[0031] Furthermore, the third heat exchange pipes of adjacent single-cell battery modules located on the same side are interconnected through connecting pipe sections.

[0032] The beneficial effects of this invention are:

[0033] This invention incorporates a heat exchange device on the top of a single battery cell. After constructing a battery module based on these single-cell battery components, the heat exchange devices of each individual battery cell can be connected to form a heat exchange channel on the top of the battery module for heat exchange. This heat exchange device primarily heats the polar terminals of the single battery cells where heat is concentrated. Furthermore, it employs a direct heat exchange method, placing a portion of the polar terminal structure directly within the heat exchange medium flow cavity, 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 compared to indirect heat exchange methods. The heat exchange medium directly acts on the polar terminal, improving the utilization efficiency of the heat exchange medium and thus enhancing the overall heat exchange efficiency of the battery. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of a single battery module in Example 1;

[0035] Figure 2a This is a cross-sectional view of a single battery module from Example 1;

[0036] Figure 2b This is another cross-sectional view of the single-cell battery assembly of Example 1;

[0037] Figure 3 This is a partial cross-sectional view of the first heat exchange tube in Example 1;

[0038] Figure 4 This is a schematic diagram of the battery module structure in Example 1;

[0039] Figure 5 This is a partial cross-sectional view of the connection between adjacent first heat exchanger pipes in Example 1;

[0040] Figure 6 This is a partial cross-sectional view of the first heat exchange tubes connected to adjacent first heat exchange tubes in Example 1.

[0041] Figure 7 This is a schematic diagram of the structure of a single battery module in Example 2;

[0042] Figure 8a This is a cross-sectional view of a single-cell battery assembly in Example 2;

[0043] Figure 8b This is another cross-sectional view of the single-cell battery assembly of Example 2;

[0044] Figure 9 This is a cross-sectional view of another single-cell battery assembly in Example 2;

[0045] Figure 10 This is a schematic diagram of the battery module structure in Example 2;

[0046] Figure 11This is a schematic diagram of the structure of a single-cell battery assembly in Example 3;

[0047] Figure 12 This is a schematic diagram of another single-cell battery assembly in Example 3;

[0048] Figure 13 This is a cross-sectional view of another single-cell battery assembly in Example 3;

[0049] Figure 14 This is an exploded view of another single-cell battery assembly in Example 3;

[0050] Figure 15 This is a cross-sectional view of the third type of single-cell battery assembly in Example 3;

[0051] Figure 16 This is a partial cross-sectional view of the connection between adjacent first heat exchanger pipes in Example 3;

[0052] Figure 17 This is a partial cross-sectional view of the connection between adjacent first heat exchanger tubes using the first tube and the second tube in Example 3.

[0053] Figure 18 This is a schematic diagram of the structure of a single-cell battery assembly in Example 4;

[0054] Figure 19 This is a schematic diagram of another single-cell battery assembly in Example 4;

[0055] The attached figures are labeled as follows:

[0056] 1. Heat exchanger; 2. Single cell; 21. Polar terminal; 211. Electrical connection; 22. Unpacking part; 23. O-ring seal; 3. First heat exchanger fitting; 31. First tube body; 32. First channel; 33. Second channel; 4. Second heat exchanger fitting; 41. Second tube body; 5. Third heat exchanger fitting; 51. Third tube body; 52. Clearance hole; 53. Sealing plate; 6. Fourth heat exchanger fitting; 7. Insulating sealant layer; 8. Top cover plate; 9. Explosion relief part; 10. Explosion relief branch pipe; 11. Liquid injection port; 12. L-shaped connecting rib; 13. Cylinder; 14. U-shaped connecting rib; 26. Connecting pipe section; 27. First pipe; 28. Second pipe. Detailed Implementation

[0057] 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.

[0058] 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.

[0059] 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.

[0060] To improve the heat dissipation performance of a battery module (also known as a battery pack), this invention discloses a single-cell battery assembly and a battery module constructed based on such a single-cell battery assembly. The single-cell battery assembly includes a single cell and a heat exchange device. The heat exchange device is used to achieve heat exchange, and its inner cavity serves as a flow cavity for the heat exchange medium. Here, heat exchange can be understood as heat dissipation or heating. When the temperature of the battery module is higher than a set threshold, the battery module is cooled by introducing a lower-temperature heat exchange medium into the heat exchange device. When the temperature of the battery module is lower than the set threshold, the battery module is heated by introducing a higher-temperature heat exchange medium into the heat exchange device. By controlling the temperature of the heat exchange medium, it can be ensured that the battery module always operates at the normal operating temperature.

[0061] This invention places a heat exchange device on top of a single battery cell. The polar terminal of the single battery cell passes through the heat exchange device, with at least a portion of the polar terminal located inside the heat exchange device and in direct contact with the heat exchange medium. The other portion of the polar terminal is located outside the heat exchange device, serving as an electrical connection. After constructing a battery module based on this type of single battery cell assembly, the heat exchange devices of each single battery cell assembly can be connected to form a heat exchange channel on top of the battery module for heat exchange.

[0062] This invention primarily uses a heat exchange device to exchange heat at the polar terminals of individual battery cells where heat is concentrated. Simultaneously, it employs a direct heat exchange method, placing a portion of the polar terminal structure directly within the heat exchange medium flow chamber, 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 compared to indirect heat exchange methods. The heat exchange medium directly acts on the polar terminal, improving the utilization efficiency of the heat exchange medium and thus enhancing the battery's heat exchange efficiency.

[0063] Heat exchange devices with different structural forms can be used. The following describes the heat exchange devices and single battery modules with different heat exchange devices in detail with reference to the accompanying drawings and specific embodiments.

[0064] Example 1

[0065] This embodiment is a first type of single-cell battery assembly, including a single-cell battery 2 and a heat exchange device 1, wherein the heat exchange device 1 includes two first heat exchange tubes 3. Specifically, as follows... Figure 1 and Figure 2a The figures shown are a schematic diagram and a cross-sectional view of the single-cell battery module in this embodiment.

[0066] In this embodiment, the single-cell battery 2 takes a prismatic battery as an example, including an outer shell, an electrode assembly located inside the outer shell, and an electrolyte. The outer shell is formed by an upper cover assembly, a cylindrical body, and a lower cover assembly. The upper cover assembly includes an upper cover plate and two terminals 21 with opposite polarities disposed on the upper cover plate. The lower cover assembly includes a lower cover plate, and may also be provided with an opening piece 22 on the lower cover plate. This opening piece 22 can detach from the lower cover plate under external force or the action of the electrolyte, and form a through hole in the lower cover plate that penetrates the inner cavity of the outer shell. The opening piece 22 adopts an existing structure, such as the opening piece 22 disclosed in Chinese Patent CN221327991U, the sealing device disclosed in Chinese Patent CN117476997A, and the opening device disclosed in CN117477117A.

[0067] In addition, this embodiment may also provide a similar opening component 22 on the upper cover plate, which is located between the two polarity terminals 21.

[0068] Figure 3 This is a partial cross-sectional view of the first heat exchanger tube 3 in this embodiment. As can be seen from the figure, the first heat exchanger tube 3 in this embodiment includes a first tube body 31, and the first tube body 31 is provided with a first channel 32 and a second channel 33.

[0069] This invention does not specifically limit the cross-sectional shape of the first tube body 31. Since the first heat exchange tube 3 in this embodiment is placed on top of the planar single-cell battery 2, considering structural regularity, from... Figure 1 As can be seen from the image, the first tube body 31 in this embodiment is a rectangular tube. In some other embodiments, a circular tube or other structural forms of tube may also be used.

[0070] The aforementioned first channel 32 is a channel opened along the length of the first tube body 31. The inner cavity of the first channel 32 serves as a flow cavity for the heat exchange medium, and the two ends of the first channel 32 serve as the inlet and outlet ends of the first heat exchange tube 3, respectively. Sealing plates can also be fixed to the two ends of the first channel 32, with openings on the sealing plates serving as the inlet and outlet ends of the first heat exchange tube 3.

[0071] The aforementioned second channel 33 allows part of the structure of the polar terminal 21 to pass through. It is a channel that penetrates the wall of the first tube body 31 and communicates with the first channel 32. In this embodiment, the second channel 33 is perpendicular to the first channel 32.

[0072] In addition, in the z-direction (the height direction of a single cell), the size of the second channel 33 is smaller than the size of the corresponding polarity terminal 21, ensuring that the top of the polarity terminal 21 extends out of the second channel 33 as an electrical connection part 211.

[0073] In this embodiment, the shapes of the two ports of the second channel 33 are adapted to the cross-sectional shape of the polar terminal 21. The two ports of the second channel 33 are circular, and the cross-section of the polar terminal 21 is also circular. The diameter of the two ports of the second channel 33 is slightly larger than the outer diameter of the polar terminal 21. In other embodiments, the shapes of the two ports of the second channel 33 and the cross-sectional shape of the polar terminal 21 may be different, as long as it is ensured that the polar terminal 21 can be inserted into the second channel 33.

[0074] from Figure 1 and Figure 2a As can be seen from the diagram, in this embodiment, the two first heat exchange tubes 3 are respectively sleeved on different polarity terminals 21 based on the second channel 33. Part of the structure of the polarity terminal 21 is located inside the first channel 32, and part of the structure is located outside the first channel 32, serving as an electrical connection part 211;

[0075] It should be noted that:

[0076] 1. Since the polarity terminal 21 of this invention is in direct contact with the heat exchange medium, an ideal heat exchange medium should possess good insulation, high specific heat capacity and thermal conductivity, good flame retardant properties, low cost, suitable operating temperature, long service life, and non-corrosiveness. In this invention, the heat exchange medium is a common insulating heat exchange medium in the prior art, which may be, but is not limited to, insulating oil and fluorinated liquid;

[0077] 2. The first heat exchange tube 3 is located on top of the single cell 2 (it may or may not be in contact with the top of the single cell 2) and is easy to contact with the polar terminal 21 of the single cell 2.

[0078] When the first heat exchange tube 3 comes into contact with the top of the single cell 2, if the polar terminal 21 is electrically connected to the top of the single cell 2 through the first heat exchange tube 3, it will cause a short circuit. Therefore, it is necessary to insulate the first heat exchange tube 3 from the top (top cover) of the single cell 2, or to insulate the first heat exchange tube 3 from the polar terminal 21. Of course, it is also possible to insulate the first heat exchange tube 3 from both the top of the single cell 2 and the polar terminal 21. That is, as long as the polar terminal 21 cannot be electrically connected to the top of the single cell 2 through the first heat exchange tube 3, it is sufficient.

[0079] The above insulation can usually be achieved in the following ways:

[0080] 2.1 By selecting the first heat exchange tube 3 made of insulating material, insulation can be achieved between the first heat exchange tube 3 and the top of the single cell 2 and the polarity terminal 21;

[0081] 2.2. The problem can be overcome by adding an insulating pad, insulating film, or insulating varnish between the top of the individual battery 2 and the first heat exchange tube 3, which uses a non-insulating material. Alternatively, an insulating pad, insulating film, or insulating varnish can be added to the inner bottom surface of the first heat exchange tube 3 (the side of the first heat exchange tube 3 closest to the top of the individual battery 2). Insulation treatment can also be applied to the tube wall of the first heat exchange tube 3, such as spraying insulating varnish or wrapping with an insulating film. An insulating sealing gasket can also be added between the polarity terminal 21 and the first heat exchange tube 3. Of course, for safety, multiple insulation methods can be combined to overcome this problem.

[0082] In this embodiment, insulation between the first heat exchange tube 3 and the polar terminal 21 and the top of the single cell 2 is achieved by using an insulating material for the first heat exchange tube 3.

[0083] Furthermore, since the heat exchange medium flows inside the first heat exchange tube 3, the sealing performance of the first heat exchange tube 3 is particularly important. To ensure the sealing performance of the first heat exchange tube 3, from Figure 2a As can be seen, in this embodiment, two annular grooves extending circumferentially are formed on each polarity terminal 21, and the two annular grooves are arranged along the z direction; and O-rings 23 are embedded in the two annular grooves. The outer rings of the two O-rings 23 are pressed against the two ports of the second channel 33 respectively, so as to achieve sealing and improve the stability of the first heat exchange tube 3.

[0084] In some other embodiments, when a metal heat exchange tube 3 is used, the polar terminal 21 and the top port of the second channel 33 can be sealed by welding (the top port mentioned here is the port near the electrical connection part 211 of the polar terminal 21, and the stability of the first heat exchange tube 3 on the polar terminal can be further improved by welding); an insulating pad is added between the first heat exchange tube 3 and the top of the single cell 2 to achieve insulation between the first heat exchange tube 3 and the top of the single cell 2.

[0085] To further improve the stability of the first heat exchange tube 3 on a single cell, such as Figure 2bAs shown, in this embodiment, an L-shaped connecting rib can be added between the first heat exchange tube 3 and the individual battery cylinder. The horizontal plate of the L-shaped connecting rib is fixedly connected to the first heat exchange tube 3, and the vertical plate of the L-shaped connecting rib is fixedly connected to the individual battery cylinder. The specific connection method can be selected according to the material of the first heat exchange tube 3. For example, in this embodiment, the first heat exchange tube 3 is made of insulating material, so the L-shaped connecting rib can be fixedly connected to the first heat exchange tube 3 and the individual battery cylinder by screws; when the first heat exchange tube 3 is made of metal, the L-shaped connecting rib can be fixedly connected to the first heat exchange tube 3 and the individual battery cylinder by welding.

[0086] When constructing a battery module using the single battery assembly of this embodiment, the first heat exchange tube 3 of each single battery located on the same side can be connected to form two heat exchange channels on the top of the battery module. The two heat exchange channels can be connected in parallel or in series to realize the heat exchange of the battery module.

[0087] It should be noted that a connecting pipe segment 26 can be connected to either the inlet or outlet end of the first heat exchanger tube 3. Taking the connection at the inlet end as an example, one connecting pipe segment 26 of the first heat exchanger tube 3 can be inserted into the outlet end of another first heat exchanger tube 3 to achieve communication between two adjacent first heat exchanger tubes 3. The connection point between the connecting pipe segment 26 and the other first heat exchanger tube 3 needs to be sealed. Figure 5 As shown. Connecting pipe sections can also be connected to the inlet and outlet of each first heat exchanger tube 3. For ease of description, the two connecting pipe sections are defined as the first pipe 27 and the second pipe 28, respectively. In two adjacent first heat exchanger tubes 3, the first pipe 27 of one first heat exchanger tube 3 and the second pipe 28 of the other first heat exchanger tube 3 are mutually sealed and inserted, as shown. Figure 6 .

[0088] The opening piece 22 of the lower cover of each individual battery can also be opened, and the inner cavity of all individual batteries can be connected by a hollow component to achieve electrolyte sharing, reduce the differences between individual batteries, and optimize the cycle performance of the battery module.

[0089] The opening piece 22 of the cover plate of each individual battery can be opened, and the inner cavity of all individual batteries can be connected by another hollow component to achieve gas sharing, gas balance, and further optimize the cycle performance of the battery module.

[0090] Example 2

[0091] This embodiment is a second type of single-cell battery assembly. Unlike embodiment 1, this embodiment uses a second heat exchange tube 4 as a heat exchange device 1.

[0092] Specifically, such as Figure 7 The diagram shown is a structural schematic of a single battery module in this embodiment.

[0093] The structure of the single cell 2 in this embodiment is the same as that in embodiment 1, and will not be described again here.

[0094] Unlike the first heat exchanger tube 3 in Embodiment 1, the second heat exchanger tube 4 in this embodiment is provided with two second channels 33, specifically as follows: Figure 7 and Figure 8a As shown, it includes a second tube body 41, which has a first channel 32 and two second channels 33. The two second channels 33 correspond one-to-one with the polarity terminals 21 of the single cell 2. That is, in this embodiment, the partial structures of the two polarity terminals 21 are located in the same first channel 32.

[0095] In this embodiment, sealing plates can be added to both ends of the first channel 32, and holes can be made in the sealing plates to serve as the inlet and outlet ends of the second heat exchange tube 4, respectively.

[0096] The second heat exchange tube 4 is disposed on the top of the single cell 2, and each polarity terminal 21 is inserted into the corresponding second channel 33, and the electrical connection part 211 of the polarity terminal 21 extends out of the second channel 33.

[0097] It should be noted that, unlike the first heat exchange tube 3, the second heat exchange tube 4 is easy to contact the polarity terminals 21 of different polarities of the same single cell 2 at the same time. Therefore, the second heat exchange tube 4 must be insulated from the polarity terminals 21 to prevent the two polarity terminals 21 of different polarities from conducting through the second heat exchange tube 4, which would cause a short circuit. When the second heat exchange tube 4 is insulated from the polarity terminals 21, the polarity terminals 21 also cannot conduct electricity with the top of the single cell 2 through the second heat exchange tube 4.

[0098] Insulation between the second heat exchange tube 4 and the polarity terminal 21 can be achieved in the following ways:

[0099] 1. By selecting the second heat exchange tube 4 made of insulating material, insulation between the second heat exchange tube 4 and the polarity terminal 21 can be achieved;

[0100] 2. The second heat exchange tube 4 is made of non-insulating material, and an insulating sealing gasket is added between the polarity terminal 21 and the second heat exchange tube 4; the tube wall of the second heat exchange tube 4 is insulated, such as by spraying insulating paint or wrapping with insulating film; for safety reasons, multiple insulation methods can be used in combination with the above methods to avoid short circuits.

[0101] This embodiment also uses a second heat exchange tube 4 with an insulating medium to achieve insulation between the second heat exchange tube 4 and the polarity terminal 21. For example... Figure 8a As shown, the sealing method between each polarity terminal 21 and the two ports of the second channel 33 is the same as in Embodiment 1, and will not be repeated here.

[0102] To improve the stability of the second heat exchange tube 4 on the individual battery, this embodiment can adopt a method similar to that in Embodiment 1, that is, an L-shaped connecting rib is added between the second heat exchange tube 4 and the individual battery casing. The horizontal plate of the L-shaped connecting rib is fixedly connected to the second heat exchange tube 4, and the vertical plate of the L-shaped connecting rib is fixedly connected to the individual battery casing. This embodiment can also use a U-shaped connecting rib, such as... Figure 8b As shown, the U-shaped connecting rib is inverted and attached to the second heat exchange tube 4, with its two sides fixedly connected to the opposite sidewalls of the individual battery cell. The specific connection method can be selected based on the material of the second heat exchange tube 4. For example, in this embodiment, the second heat exchange tube 4 is made of insulating material, so the U-shaped connecting rib and the individual battery cell can be fixedly connected using screws; when a metal second heat exchange tube 4 is used, the U-shaped connecting rib and the individual battery cell can be fixedly connected using welding.

[0103] Furthermore, unlike Embodiment 1, in this embodiment, after the second heat exchange tube 4 is placed on top of the individual battery, its projection basically covers the upper cover of the individual battery. If the explosion vent (also called explosion vent, explosion-proof part, explosion-proof port, etc.) is placed on the upper cover of the individual battery, and the gap between the second heat exchange tube 4 and the upper cover is too small, or even non-existent, the thermal runaway flue gas may not be able to be discharged in time due to the obstruction of the second heat exchange tube 4, posing a certain safety hazard. In this embodiment, this problem can be solved by the following two solutions:

[0104] Option 1: Adjust the position of the explosion vent to avoid the second heat exchange tube 4. For example, the explosion vent can be set in the lower cover plate.

[0105] Option 2: Figure 9 As shown, another clearance channel perpendicular to the first channel is opened in the second heat exchange tube; the clearance channel corresponds to the explosion venting part 9 of the upper cover plate; an explosion venting branch pipe 10 is provided on the upper cover plate 8, one end of the explosion venting branch pipe 10 is sealed to the upper cover plate area around the explosion venting part 9, and the other end passes through the clearance channel and extends out.

[0106] Similarly, if the injection port is located below the second heat exchanger tube 4, making injection inconvenient, then the injection port should also be avoided from the second heat exchanger tube 4. It can be located at the edge of the upper cover plate, such as... Figure 9 As shown. Additionally, due to the obstruction of the second heat exchange tube, it is not convenient to install an opening device on the upper cover plate in this embodiment.

[0107] Similar to Example 1, when constructing a battery module using the individual cells of this example, the second heat exchange tubes 4 of each individual cell can be connected, such as... Figure 10As shown (the specific connection method can be connected with the first heat exchange tube 3 in Embodiment 1), a heat exchange channel is formed on the top of the battery module, and heat exchange of the battery module is realized based on the heat exchange channel. The opening piece of the lower cover of each individual battery can be opened, and the inner cavity of all individual batteries can be connected by a hollow component to realize electrolyte sharing, reduce the difference between individual batteries, and optimize the cycle performance of the battery module.

[0108] Example 3

[0109] This embodiment is a third type of single-cell battery assembly. Unlike embodiment 1, this embodiment uses two third heat exchange tubes 5 as heat exchange devices 1, and the two third heat exchange tubes 5 correspond one-to-one with the two polarity terminals 21 of the single-cell battery 2.

[0110] Specifically, such as Figure 11 , Figure 12 and Figure 13 As shown, Figure 11 and Figure 12 These are schematic diagrams of two different sized single-cell battery modules in this embodiment. Figure 13 for Figure 12 The cross-sectional view corresponding to the single battery module shown;

[0111] in Figure 11 The single cell 2 shown is the same as the above embodiment, and will not be described again here. Figure 13 The single cell 2 is relatively large, and its terminals are elongated. The rest of the structure is the same as in the above embodiment.

[0112] In this embodiment, the third heat exchange tube 5 is a half tube. The half tube can be understood as dividing the whole tube into two halves along the axial direction, and each half is a half tube.

[0113] Similarly, since the top cover plate in this embodiment is a rectangular plate, for structural regularity, the third heat exchange tube 5 is a half-tube with a rectangular cross-section, and a clearance hole 52 is opened on the tube wall of the third heat exchange tube 5 (see Figure 14 The electrical connection portion 211 of the polarity terminal 21 extends out.

[0114] Combination Figure 14 As shown, when fixing the third heat exchanger tube 5 to the upper cover plate, it needs to be snapped onto the upper cover plate and sealed to it. The space between the third heat exchanger tube 5 and the upper cover plate serves as the heat exchange medium flow chamber. Part of the structure of the polarity terminal 21 is located within the heat exchange medium flow chamber. The electrical connection portion 211 of the polarity terminal 21 extends out of the clearance hole 52, and the polarity terminal 21 is sealed to the clearance hole 52. A sealing plate 53 can be fixed to the two open ends opposite to the half-pipe, and an opening can be made in the sealing plate 53 as the inlet end and the outlet end.

[0115] Compared to the first heat exchanger 3 and the second heat exchanger 4, the heat exchange medium in the third heat exchanger 5 can also directly contact the upper cover plate and act directly on the upper cover plate, resulting in a better heat exchange effect.

[0116] It should be noted that:

[0117] 1. Since the polar terminal 21 of this invention is in direct contact with the heat exchange medium, an ideal heat exchange medium should possess characteristics such as good insulation, high specific heat capacity and thermal conductivity, good flame retardancy, low cost, suitable operating temperature, long service life, and non-corrosiveness. In this invention, the insulating heat exchange medium is a common insulating heat exchange medium in the prior art, which can be, but is not limited to, insulating oil and fluorinated liquid.

[0118] 2. The third heat exchange tube 5 is easily in contact with the polarity terminal 21, and the third heat exchange tube 5 is in direct contact with the upper cover plate. If the third heat exchange tube 5 is conductive, the positive and negative polarity terminals 21 of the same single cell 2 will be directly connected through the third heat exchange tube 5, resulting in a short circuit. Therefore, the third heat exchange tube 5 is preferably made of insulating material. When a non-insulating material is used, an insulating sealing ring can be added between the polarity terminal 21 and the third heat exchange tube 5 to overcome this problem. Alternatively, the third heat exchange tube 5 can be insulated, such as by spraying insulating paint or wrapping with an insulating film. For safety, multiple insulation methods can be combined to overcome this problem.

[0119] In this embodiment, an insulating third heat exchange tube 5 is selected. Two third heat exchange tubes 5 are respectively fastened to the upper cover plate area where the two polarity terminals 21 are located. In order to ensure that the electrical connection part 211 of the polarity terminal 21 can pass smoothly through the clearance hole 52 on the third heat exchange tube 5, the orthographic projection area of ​​the clearance hole 52 in the xy plane needs to be slightly larger than the orthographic projection area of ​​the corresponding electrical connection part 211 of the polarity terminal 21 in the xy plane. In the z direction, the vertical distance between the bottom end of the polarity terminal 21 and the top plate of the third heat exchange tube 5 needs to be smaller than the size of the polarity terminal 21. This ensures that the electrical connection part 211 of the corresponding polarity terminal 21 can pass smoothly through the corresponding clearance hole 52.

[0120] Typically, the shape of the clearance hole 52 is adapted to the cross-sectional shape of the electrical connection portion 211 of the polarity terminal 21. If the clearance hole 52 is a circular hole and the cross-section of the electrical connection portion 211 of the polarity terminal 21 is circular, then the diameter of the clearance hole 52 needs to be slightly larger than the outer diameter of the electrical connection portion 211 of the polarity terminal 21. If the clearance hole 52 is a square hole and the cross-section of the electrical connection portion 211 of the polarity terminal 21 is square, then the area of ​​the clearance hole 52 needs to be slightly larger than the cross-sectional area of ​​the electrical connection portion 211 of the polarity terminal 21. Of course, the shape of the clearance hole 52 may not be adapted to the cross-sectional shape of the electrical connection portion 211 of the polarity terminal 21, as long as it is ensured that the electrical connection portion 211 of the polarity terminal 21 can pass smoothly through the corresponding clearance hole 52 and achieve a seal between the two.

[0121] When a liquid heat exchange medium is used, the sealing performance of the third heat exchange pipe fitting 5 is particularly important. To ensure the sealing performance of the third heat exchange pipe fitting 5, from Figure 15 As can be seen, in this embodiment, a stepped structure is provided along the circumference of each polarity terminal 21. When the electrical connection portion 211 of the polarity terminal 21 extends out of the clearance hole 52, the area of ​​the third heat exchange tube 5 around the clearance hole 52 is sealed and pressed against the stepped surface. In addition, an insulating sealant layer 7 can be laid on the stepped surface, and the area of ​​the third heat exchange tube 5 around the clearance hole 52 is pressed onto the insulating sealant layer 7. At the same time, the insulating sealant penetrates into the gap between the clearance hole 52 and the polarity terminal 21, thereby achieving a seal between the polarity terminal 21 and the clearance hole 52. In some other embodiments, an O-ring 23 can also be fitted between the polarity terminal 21 and the clearance hole 52 to achieve a seal between them.

[0122] An annular groove can be provided on the upper cover plate, and an annular protrusion matching the annular groove can be provided on the open end face of the third heat exchange tube 5. The annular protrusion is inserted into the annular groove, and sealant is applied to the mating part to achieve sealing and fixing of the third heat exchange tube 5 and the upper cover plate.

[0123] In some other embodiments, a third heat exchange tube 5 made of metal can be selected. In order to ensure the insulation between the polar terminal 21 and the clearance hole 52, an O-ring can be added between them to achieve both insulation and sealing. The third heat exchange tube 5 and the upper cover plate can be sealed and fixed by welding.

[0124] Similar to Example 1, when constructing a battery module using the individual cells in this example, the third heat exchange tubes 5 of each individual cell can be connected to form two heat exchange channels on the top of the battery module. The two heat exchange channels can be connected in parallel or in series, and the heat exchange of the battery module is achieved based on the two heat exchange channels.

[0125] It should be noted that a connecting pipe segment 26 can be connected to either the inlet or outlet end of the third heat exchanger fitting 5. Taking the connection at the inlet end as an example, one connecting pipe segment 26 of the third heat exchanger fitting 5 can be inserted into the outlet end of another third heat exchanger fitting 5 to achieve communication between the two adjacent third heat exchanger fittings 5. The connection point between the connecting pipe segment 26 and the other third heat exchanger fitting 5 needs to be sealed. Figure 16 As shown. Connecting pipe sections can also be connected to the inlet and outlet of each third heat exchanger 5. For ease of description, the two connecting pipe sections are defined as the first pipe 27 and the second pipe 28, respectively. In two adjacent third heat exchanger 5s, the first pipe 27 of one third heat exchanger 5 and the second pipe 28 of the other third heat exchanger 5 are mutually sealed and inserted, as shown. Figure 17 .

[0126] The packaging can be opened by opening the bottom cover of each individual battery cell, and a hollow component can be used to connect the internal cavities of all individual batteries, enabling electrolyte sharing, reducing the differences between individual batteries, and optimizing the cycle performance of the battery module. The packaging can also be opened by opening the top cover of each individual battery cell, and another hollow component can be used to connect the internal cavities of all individual batteries, enabling gas sharing, achieving gas balance, and further optimizing the cycle performance of the battery module.

[0127] Example 4

[0128] This embodiment is the fourth type of single-cell battery module. Unlike embodiment 3, this embodiment uses a fourth heat exchange tube 6 as the heat exchange device, and the specific structure is as follows: Figure 18 and Figure 19 As shown.

[0129] The structure of cell 2 in this embodiment is the same as that in embodiment 3, and will not be described again here.

[0130] Unlike the third heat exchange tube 5 in Embodiment 3, the fourth heat exchange tube 6 in this embodiment has two clearance holes 52 on its tube wall, and the two clearance holes 52 correspond one-to-one with the two polarity terminals 21 of the single cell.

[0131] In this embodiment, the structures of the two polar terminals 21 are located within the same heat exchange medium flow chamber. Alternatively, sealing plates can be added to both ends of the fourth heat exchange tube 6, with openings in the sealing plates serving as the inlet and outlet ends of the fourth heat exchange tube 6, respectively.

[0132] In this embodiment, the fourth heat exchange tube 6 made of insulating material is selected. The sealing method between each polarity terminal 21 and the clearance hole 52 is the same as in embodiment 3, and will not be repeated here. The sealing method between the fourth heat exchange tube 6 and the upper cover plate is also the same as in embodiment 3, and will not be repeated here.

[0133] This embodiment can adopt a structure similar to that of Embodiment 2, adjusting the position of the explosion vent (or adding an explosion vent branch pipe) and the injection port so that the fourth heat exchange pipe 6 does not affect the normal use of the explosion vent and the injection port. Similarly, due to the obstruction of the fourth heat exchange pipe 6, it is not convenient to install an opening device on the upper cover plate.

[0134] Similar to the above embodiments, when constructing a battery module using the individual cells in this embodiment, the fourth heat exchange tubes 6 of each individual cell can be connected to form a heat exchange channel at the top of the battery module, and the heat exchange of the battery module can be realized based on the heat exchange channel.

[0135] The packaging can be opened by opening the bottom cover of each individual battery cell, and a hollow component can be used to connect the inner cavities of all individual batteries, so as to achieve electrolyte sharing, reduce the differences between individual batteries, and optimize the cycle performance of the battery module.

Claims

1. A monobloc battery assembly characterized by: The battery cell and the heat exchange device are included. The heat exchange device is located on the top of the battery cell, and the inner cavity of the heat exchange device serves as a flow cavity of the heat exchange medium. At least part of the structure of the polar terminal of the battery cell is located in the flow cavity of the heat exchange medium and directly contacts with the heat exchange medium. The other part of the structure of the polar terminal is located outside the heat exchange device and serves as an electrical connection part.

2. The monobloc cell assembly of claim 1, wherein: The heat exchange device includes two first heat exchange pipe fittings, each of which includes a first pipe body, and the first pipe body is provided with a first channel and a second channel. The two polar terminals of the battery cell correspond to the two first heat exchange pipe fittings. The two ports of the second channel are sealed from the polar terminals.

3. The monobloc cell assembly of claim 1, wherein: The heat exchange device includes a second heat exchange pipe fitting, which includes a second pipe body provided with a first channel and two second channels. The inner cavity of the first channel serves as a flow cavity of the heat exchange medium. The second channel is perpendicular to the first channel and penetrates the first channel. The two polar terminals of the battery cell correspond to the two second channels. The two ports of the second channel are sealed from the polar terminals.

4. The single cell assembly of claim 2 or 3, wherein: Two annular grooves are formed along the circumference of the polar terminal and arranged along the z direction.

5. The monobloc cell assembly of claim 1, wherein: Two O-shaped sealing rings are embedded in the two annular grooves, and the outer rings of the two O-shaped sealing rings are pressed against the two ports of the second channel. The heat exchange device includes two third heat exchange pipe fittings corresponding to the two polar terminals of the battery cell. The third heat exchange pipe fitting is a half pipe provided with an avoiding hole on the wall thereof. The third heat exchange pipe fitting is buckled and sealed on the upper cover plate of the battery cell.

6. The monobloc cell assembly of claim 1, wherein: At least part of the structure of the polar terminal of the battery cell is located in the flow cavity of the heat exchange medium, and the other part of the structure of the polar terminal extends out of the avoiding hole of the corresponding third heat exchange pipe fitting and serves as an electrical connection part. The polar terminal is sealed from the corresponding avoiding hole. The heat exchange device includes a fourth heat exchange pipe fitting, which is a half pipe provided with two avoiding holes corresponding to the two polar terminals of the battery cell. The fourth heat exchange pipe fitting is buckled and sealed on the upper cover plate of the battery cell.

7. The monobloc cell assembly of claim 1, wherein: At least part of the structure of the polar terminal of the battery cell is located in the flow cavity of the heat exchange medium, and the other part of the structure of the polar terminal extends out of the corresponding avoiding hole and serves as an electrical connection part.

8. The monobloc cell assembly of claim 1, wherein: The polar terminal is sealed from the corresponding avoiding hole.

9. The monobloc cell assembly of claim 1, wherein: The material of the heat exchange device is an electrically insulating material. An unpacking piece is arranged on the lower cover plate of the battery cell. A connecting pipe section is connected to the inlet end and / or outlet end of the heat exchange device.

10. A battery module, characterized by: The single cell assembly comprises the heat exchange device of any one of claims 1 to 9; the heat exchange devices of adjacent single cell assemblies are communicated with each other.

11. The battery module of claim 10, wherein: The first heat exchange pipe fittings of the adjacent single cell assemblies located on the same side are communicated with each other through the connecting pipe segments.

12. The battery module of claim 10, wherein: The third heat exchange pipe fittings of the adjacent single cell assemblies located on the same side are communicated with each other through the connecting pipe segments.

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