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 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; a functional structure is arranged on the single battery polarity terminal and is used for increasing the heat exchange area of the single battery polarity terminal; 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; the polarity terminal penetrates through the heat exchange device, and the part provided with the functional structure is located in the heat exchange medium flowing cavity. 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] The utility model belongs to the field of batteries, in particular to a single battery assembly and a battery module. Background Art

[0002] Battery modules generate heat during operation. Failure to dissipate heat promptly can impact their performance and service life, and may even lead to thermal runaway, posing a safety hazard. Therefore, effective thermal management of battery modules is crucial for ensuring their safe and stable operation. Summary of the Invention

[0003] The purpose of the utility model is to provide a single battery assembly and a battery module, which can overcome the safety hazard caused by heating of the battery module.

[0004] A first aspect of the present invention provides a single cell assembly, comprising a single cell and a heat exchange device;

[0005] A functional structure is provided on the polarity terminal of the single battery, which is used to increase the heat exchange area of ​​the polarity terminal;

[0006] The heat exchange device is located on the top of the single battery, and the inner cavity of the heat exchange device serves as the heat exchange medium flow cavity;

[0007] The polarity terminals of the single battery pass through the heat exchange device, and the side walls of the extreme terminals are sealed from the heat exchange device; the part of the polarity terminal with a functional structure is located in the heat exchange medium flow cavity and is in direct contact with the heat exchange medium; the other part of the polarity terminal structure is located outside the heat exchange device and serves as an electrical connection part.

[0008] This utility model installs a heat exchange device on top of a single cell. After constructing a battery module based on this single cell assembly, the heat exchange devices of each single cell assembly can be connected to form a heat exchange channel on top of the battery module to exchange heat for the battery module. This heat exchange device mainly exchanges heat for the polarity terminals of the single cell, where heat is more concentrated. At the same time, it uses a direct heat exchange method, placing part of the structure of the polarity terminal directly within the heat exchange medium flow cavity, so that the polarity terminal and the heat exchange medium are in direct contact, achieving heat exchange at the polarity terminal. Compared with indirect heat exchange methods, this method has a shorter heat exchange path, and the heat exchange medium directly acts on the polarity terminal, which improves the utilization efficiency of the heat exchange medium and the heat exchange efficiency of the battery.

[0009] At the same time, without affecting the conductive performance of the polarity terminal, a functional structure is set on the polarity terminal to increase the heat exchange area of ​​the polarity terminal. The part with the functional structure is placed in the heat exchange device to exchange heat with the heat exchange medium. Compared with the polarity terminal without a functional structure, it has a larger heat exchange area, thereby achieving a better heat exchange effect.

[0010] Furthermore, the functional structure comprises n first annular grooves, where n is an integer greater than or equal to 1; each first annular groove extends circumferentially along the side of the polarity terminal, and the n first annular grooves are arranged along the height direction of the polarity terminal. The annular grooves are easy to process, resulting in a lower cost for the polarity terminal.

[0011] Furthermore, the functional structure can also be a through-hole provided on the polarity terminal, the through-hole penetrating the polarity terminal along the x-direction. A plurality of dividing ribs can also be provided on the inner wall of the through-hole; the plurality of dividing ribs are evenly distributed along the circumference of the through-hole, and each dividing rib extends axially along the through-hole. By providing dividing ribs within the through-hole, the contact area between the heat exchange medium and the polarity terminal can be further increased, thereby increasing the heat exchange area and further improving the heat exchange effect. In addition, the plurality of dividing ribs are evenly distributed along the circumference of the through-hole, so that the temperature uniformity of each part of the polarity terminal is better. Each dividing rib extends axially along the through-hole, without affecting the fluidity of the heat transfer medium within the through-hole.

[0012] The heat exchange device can adopt different structural forms. The present invention provides at least the following four types:

[0013] The first heat exchange device:

[0014] The heat exchange device includes two first heat exchange pipes, each of which includes a first pipe body, wherein a first channel and a second channel are provided in the first pipe body; the inner cavity of the first channel serves as a heat exchange medium flow cavity; the second channel is perpendicular to the first channel and is in communication with the first channel;

[0015] The two polarity terminals of the single battery correspond one-to-one to the two first heat exchange tubes; the portion of each polarity terminal with a functional structure is inserted into the first channel of the corresponding first heat exchange tube through the second channel, directly contacting the heat exchange medium in the first channel, and the other portion of the structure extends out of the second channel to serve as an electrical connection portion; the two ports of the second channel are sealed from the polarity terminals.

[0016] The second heat exchange device:

[0017] The heat exchange device includes a second heat exchange tube, which includes a second tube body. The second tube body is provided with 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 is connected to the first channel. The two polarity terminals of the single battery correspond to the two second channels one by one. The portion of each polarity terminal provided with a functional structure 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 to serve as an electrical connection portion.

[0018] The two ports of the second channel are sealed with the polarity terminals.

[0019] In the above two heat exchange device structures, the parts of the polarity terminals provided with functional structures can be located in the heat exchange medium flow cavity, in direct contact with the heat exchange medium, thereby achieving effective heat dissipation.

[0020] The third heat exchange device:

[0021] The heat exchange device includes two third heat exchange pipes, and the two third heat exchange pipes correspond one to one with the two polarity terminals of the single battery;

[0022] The third heat exchange pipe is a half pipe with an avoidance hole formed on the wall of the half pipe; the third heat exchange pipe is buckled and sealed on the upper cover of the single cell; the space formed between the third heat exchange pipe and the upper cover of the single cell serves as a heat exchange medium flow chamber;

[0023] The functional structure of the polarity terminal of the single battery is located in the heat exchange medium flow cavity, and the other part of the structure extends out of the avoidance hole corresponding to the third heat exchange pipe to serve as the electrical connection part;

[0024] The polarity terminals and the corresponding avoidance holes are sealed.

[0025] The fourth heat exchange device:

[0026] The heat exchange device includes a fourth heat exchange pipe, which is a half pipe. Two avoidance holes are opened on the wall of the half pipe. The two avoidance holes correspond to the two polarity terminals of the single battery one by one.

[0027] The fourth heat exchange pipe is buckled and sealed on the upper cover of the single cell; the space formed between the fourth heat exchange pipe and the upper cover of the single cell serves as a heat exchange medium flow cavity;

[0028] The functional structures of the two polarity terminals of the single battery are both located in the heat exchange medium flow cavity, and the other part of the structure extends out of the corresponding avoidance hole to serve as the electrical connection part;

[0029] The polarity terminals and the corresponding avoidance holes are sealed.

[0030] In the third and fourth heat exchange devices described above, part of the structure of the polarity terminals and the portion of the single cell upper cover plate provided with the functional structure are in direct contact with the heat exchange medium, thus achieving a better heat exchange effect.

[0031] Furthermore, the heat exchange device is made of electrically insulating material, which can avoid short circuit problems to the greatest extent.

[0032] Furthermore, an opening piece may be provided on the lower cover of the single cell. When a large-capacity battery is constructed based on such single cells, the opening piece may be opened to connect the electrolytes of the individual cells, thereby achieving an electrolyte sharing effect.

[0033] Furthermore, a connecting pipe section may be connected to the inlet and / or outlet of the heat exchange device, so that the heat exchange devices of adjacent single cells can be connected based on the connecting pipe section.

[0034] The second aspect of the present invention provides a battery module, comprising the above-mentioned single battery assembly; the heat exchange devices of adjacent single battery assemblies are interconnected through connecting pipe sections, forming a heat exchange channel on the top of the battery module to achieve heat exchange of the battery module.

[0035] The beneficial effects of the utility model are:

[0036] This utility model installs a heat exchange device on top of a single cell. After constructing a battery module based on this single cell assembly, the heat exchange devices of each single cell assembly can be connected to form a heat exchange channel on top of the battery module to exchange heat for the battery module. This heat exchange device mainly exchanges heat for the polarity terminals of the single cell, where heat is more concentrated. At the same time, it uses a direct heat exchange method, placing part of the structure of the polarity terminal directly within the heat exchange medium flow cavity, so that the polarity terminal and the heat exchange medium are in direct contact, achieving heat exchange at the polarity terminal. Compared with indirect heat exchange methods, this method has a shorter heat exchange path, and the heat exchange medium directly acts on the polarity terminal, which improves the utilization efficiency of the heat exchange medium and the heat exchange efficiency of the battery.

[0037] At the same time, without affecting the conductive performance of the polarity terminal, a functional structure is set on the polarity terminal to increase the heat exchange area of ​​the polarity terminal. The part with the functional structure is placed in the heat exchange device to exchange heat with the heat exchange medium. Compared with the polarity terminal without a functional structure, it has a larger heat exchange area, thereby achieving a better heat exchange effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic structural diagram of a single battery assembly according to Example 1;

[0039] Figure 2a is a cross-sectional view of a single cell assembly of Example 1;

[0040] Figure 2b is another cross-sectional view of the single cell assembly of Example 1;

[0041] Figure 3 is a partial cross-sectional view of the first heat exchange pipe member in Example 1;

[0042] Figure 4 Schematic diagram of the structure of the battery module in Example 1;

[0043] Figure 5 A partial cross-sectional view of connecting adjacent first heat exchange pipe members using connecting pipe sections in Example 1;

[0044] Figure 6A partial cross-sectional view of connecting adjacent first heat exchange pipe members using a first pipe and a second pipe in Example 1;

[0045] Figure 7 is a cross-sectional view of a single cell in Example 2;

[0046] Figure 8 is a cross-sectional view of the upper cover assembly in Example 2;

[0047] Figure 9 This is a schematic structural diagram of a single cell assembly according to Example 3;

[0048] Figure 10a is a cross-sectional view of a single cell assembly of Example 3;

[0049] Figure 10b is another cross-sectional view of the single cell assembly of Example 3;

[0050] Figure 11 is a cross-sectional view of another single battery assembly of Example 3;

[0051] Figure 12 This is a schematic structural diagram of the battery module of Example 3;

[0052] Figure 13 This is a schematic structural diagram of a single battery assembly according to Example 4;

[0053] Figure 14 is a cross-sectional view of a single cell assembly in Example 4;

[0054] Figure 15 is a cross-sectional view of a third single cell assembly according to Example 4;

[0055] Figure 16 A partial cross-sectional view of connecting adjacent first heat exchange pipe members using connecting pipe segments in Example 4;

[0056] Figure 17 A partial cross-sectional view of connecting adjacent first heat exchange pipe members using a first pipe and a second pipe in Example 4;

[0057] Figure 18 This is a schematic structural diagram of a single battery assembly according to Example 5;

[0058] The accompanying drawings are denoted as follows:

[0059] 1. Heat exchange device; 2. Single battery; 21. Polarity terminal; 211. Electrical connection part; 22. Opening piece; 23. O-ring; 24. Through hole; 25. First annular groove; 29. ​​Partition rib; 3. First heat exchange pipe; 31. First pipe body; 32. First channel; 33. Second channel; 4. Second heat exchange pipe; 41. Second pipe body; 5. Third heat exchange pipe; 52. Avoidance hole; 53. Sealing plate; 6. Fourth heat exchange pipe; 7. Insulating sealant layer; 8. Upper cover; 9. Explosion venting part; 10. Explosion venting branch pipe; 11. Liquid filling port; 12. L-shaped connecting rib; 13. Cylinder; 14. U-shaped connecting rib; 26. Connecting pipe section; 27. First pipe; 28. Second pipe. DETAILED DESCRIPTION

[0060] To make the above-mentioned purposes, features, and advantages of the present invention more clearly understood, the following detailed description of the specific embodiments of the present invention is given in conjunction with the accompanying drawings. It is obvious that the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in this field without creative work should fall within the scope of protection of the present invention.

[0061] In the following description, many specific details are set forth to facilitate 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 may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0062] In the description of this utility model, it should be noted that the terms "top," "bottom," and so on, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first, second, third, fourth, etc." are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0063] In order to improve the heat dissipation performance of a battery module (also referred to as a battery pack), the utility model discloses a single cell assembly and a battery module constructed based on such a single cell assembly, the single cell assembly comprising a single cell and a heat exchange device; a functional structure is provided on the polarity terminal of the single cell, the functional structure being used to increase the heat exchange area of ​​the polarity terminal; the heat exchange device is used to achieve heat exchange, and its inner cavity serves as a heat exchange medium flow cavity; the heat exchange here 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 heat exchange medium with a lower temperature 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 heat exchange medium with a higher temperature 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 a normal operating temperature.

[0064] This utility model places a heat exchanger on top of a single cell. The polarity terminals of the single cell extend through the heat exchanger. The functional structure of the polarity terminals is located inside the heat exchanger, in direct contact with the heat exchange medium. The other portion of the polarity terminals is located outside the heat exchanger, serving as an electrical connection. When a battery module is constructed based on this type of single cell assembly, the heat exchangers of each single cell assembly can be connected, forming a heat exchange channel at the top of the battery module to exchange heat within the battery module.

[0065] This utility model uses a heat exchange device to primarily exchange heat at the polarity terminals of the single battery cells, where heat is most concentrated. Simultaneously, a direct heat exchange method is employed, placing a portion of the polarity terminal structure directly within the heat exchange medium flow cavity, allowing direct contact between the polarity terminal and the heat exchange medium. This achieves heat exchange at the polarity terminal. Compared to indirect heat exchange methods, this method has a shorter heat exchange path, with the heat exchange medium acting directly on the polarity terminal, increasing the utilization efficiency of the heat exchange medium and improving the heat exchange efficiency of the battery. Furthermore, compared to polarity terminals without functional structures, this method has a larger heat exchange area, resulting in better heat exchange results.

[0066] Heat exchange devices of different structural forms may be used. The heat exchange devices and single cell assemblies with different heat exchange devices are described in detail below with reference to the accompanying drawings and specific embodiments.

[0067] Example 1

[0068] This embodiment is a first type of single cell assembly, comprising a single cell 2 and a heat exchange device 1, wherein the heat exchange device 1 comprises two first heat exchange pipes 3. Figure 1 and Figure 2a 2 and 3 are a schematic structural diagram and a cross-sectional view of the single cell assembly of this embodiment.

[0069] The single cell 2 in this embodiment is a square-shell battery, which includes an outer shell, an electrode assembly and an electrolyte located inside the outer shell. The outer shell is formed by an upper cover assembly, a cylinder and a lower cover assembly.

[0070] The upper cover assembly includes an upper cover plate and two polarity terminals 21 with opposite polarities arranged on the upper cover plate.

[0071] In this embodiment, the polarity terminal 21 is cylindrical, with two first annular grooves 25 defined on its side. These grooves run along the height of the polarity terminal 21, each extending circumferentially along the side of the polarity terminal 21. The two first annular grooves increase the heat exchange area of ​​this portion of the polarity terminal 21. When placed within the interior of the heat exchange device 1, this portion has a larger heat exchange area than a polarity terminal 21 with smooth sides, resulting in a better heat exchange effect.

[0072] In some other embodiments, the number of the first annular grooves 25 and their dimensions such as groove width and groove depth can be adjusted as required, specifically on the premise that the conductive performance of the polarity terminal 21 is not affected.

[0073] In some other embodiments, other structures can be processed on the polarity terminal 21 to increase the heat exchange area of ​​the polarity terminal 21. For the convenience of description, in the present invention, the structures that can increase the heat exchange area of ​​the polarity terminal 21 are collectively referred to as functional structures; such functional structures can include dot-shaped pits, protrusions, etc. located on the side of the polarity terminal 21; compared with the above-mentioned functional structures, the first annular groove 25 structure of this embodiment is easy to process and has a lower processing cost.

[0074] In addition, the present invention does not limit the cross-sectional shape of the polarity terminal 21 . For example, unlike this embodiment, in some other embodiments, a column with a rectangular cross-section may be used as the polarity terminal 21 .

[0075] In this embodiment, an opening member 22 may be further provided on the upper cover, located between the two polarity terminals 21. Such an opening member 22 can be separated from the upper cover by an external force or electrolyte, thereby forming a through hole in the upper cover that penetrates the inner cavity of the outer shell. The opening member 22 may employ an existing structure, such as the opening member 22 disclosed in Chinese Patent CN221327991 U, the sealing device disclosed in Chinese Patent CN117476997A, or the opening device disclosed in CN117477117A.

[0076] The lower cover assembly includes a lower cover plate, and a similar opening piece 22 can also be set on the lower cover plate. Under the action of external force or electrolyte, such an opening piece 22 can be separated from the lower cover plate and form a through hole in the lower cover plate that penetrates the inner cavity of the outer shell.

[0077] Figure 3 3 is a partial cross-sectional view of the first heat exchange pipe 3 of this embodiment. As can be seen from the figure, the first heat exchange pipe 3 of this embodiment includes a first pipe body 31, and a first channel 32 and a second channel 33 are provided in the first pipe body 31.

[0078] The utility model 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 the top of the planar single battery 2, considering the structural regularity, Figure 1 As can be seen from the figure, the first tube body 31 of this embodiment is a rectangular tube. In other embodiments, a circular tube or a tube of other structural forms may also be used.

[0079] The first channel 32 is a channel extending along the length of the first tube body 31. The interior of the first channel 32 serves as a flow chamber for the heat exchange medium, and the ends of the first channel 32 serve as the inlet and outlet of the first heat exchange tube 3, respectively. Sealing plates may be fixed to the ends of the first channel 32, with openings formed in the sealing plates serving as the inlet and outlet of the first heat exchange tube 3.

[0080] The second passage 33 is for the portion of the polarity terminal 21 with the functional structure to pass through. It is a passage that penetrates the wall of the first tube body 31 and is connected to the first passage 32 . In this embodiment, the second passage 33 is perpendicular to the first passage 32 .

[0081] In addition, in the z direction (height direction of the single battery), 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 as the electrical connection portion 211 extends out of the second channel 33 .

[0082] In this embodiment, the shapes of the two ports of the second channel 33 are adapted to the cross-sectional shape of the polarity terminal 21. The two ports of the second channel 33 are circular in shape, the cross-sectional shape of the polarity terminal 21 is also circular, and the diameter of the two ports of the second channel 33 is slightly larger than the outer diameter of the polarity terminal 21. In other embodiments, the shapes of the two ports of the second channel 33 and the cross-sectional shape of the polarity terminal 21 can be different, as long as the polarity terminal 21 can be inserted into the second channel 33.

[0083] from Figure 1 and Figure 2a As can be seen in the figure, in this embodiment, the two first heat exchange tubes 3 are respectively mounted on different polarity terminals 21 based on the second channel 33. The functional 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 the electrical connection portion 211;

[0084] It should be noted that:

[0085] 1. Because the polarity terminal 21 of the present invention is in direct contact with the heat exchange medium, the ideal heat exchange medium should have good insulation, high specific heat capacity and thermal conductivity, good flame retardancy, low cost, suitable operating temperature, long life, and non-corrosive properties. In the present invention, the 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;

[0086] 2. The first heat exchange pipe 3 is located on the top of the single battery 2 (it may or may not be in contact with the top of the single battery 2);

[0087] When the first heat exchange tube 3 is in contact with the polarity terminal 21 and the top of the single cell 2 at the same time, if the polarity terminal 21 is electrically connected to the top of the single cell 2 through the first heat exchange tube 3, a short circuit will occur. Therefore, it is necessary to insulate the first heat exchange tube 3 from the top of the single cell 2 (upper cover), or to insulate the first heat exchange tube 3 from the polarity 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 polarity terminal 21. That is, it is sufficient to ensure that the polarity terminal 21 cannot be electrically connected to the top of the single cell 2 through the first heat exchange tube 3.

[0088] The above insulation can usually be achieved in the following ways:

[0089] 2.1. The first heat exchange pipe 3 is made of insulating material to achieve insulation between the first heat exchange pipe 3 and the top of the single battery 2 and the polarity terminal 21;

[0090] 2.2. If the first heat exchange tube 3 is made of a non-insulating material, this problem can be overcome by adding an insulating pad, insulating film, or insulating paint between the top of the single cell 2 and the first heat exchange tube 3. This problem can also be overcome by adding an insulating pad, insulating film, or insulating paint to the inner bottom surface of the first heat exchange tube 3 (the surface of the first heat exchange tube 3 inside the first heat exchange tube 3 close to the top of the single cell 2). The wall of the first heat exchange tube 3 can also be insulated, such as by spraying insulating paint or wrapping it with insulating film. This problem can also be overcome by adding an insulating sealing gasket between the polarity terminal 21 and the first heat exchange tube 3. Of course, for the sake of safety, the above methods can be combined to adopt multiple insulation methods to overcome this problem.

[0091] In this embodiment, the first heat exchange tube 3 made of insulating material is used to achieve insulation between the first heat exchange tube 3 and the polarity terminal 21 and the top of the single battery 2 .

[0092] In addition, since the heat exchange medium flows in the first heat exchange pipe 3, the sealing performance of the first heat exchange pipe 3 is particularly important. In order to ensure the sealing performance of the first heat exchange pipe 3, Figure 2aIt can be seen that in this embodiment, two annular grooves extending along the circumference of each polarity terminal 21 are provided, and the two annular grooves are arranged along the z direction; and O-rings 23 are embedded in the two annular grooves, and the outer rings of the two O-rings 23 are respectively pressed against the two ports of the second channel 33, thereby achieving sealing and improving the stability of the first heat exchange pipe 3.

[0093] In some other embodiments, when a first heat exchange tube 3 made of metal is used, the sealing between the polarity terminal 21 and the top port of the second channel 33 can be achieved by welding (the top port mentioned here is the port close to the electrical connection part 211 of the polarity terminal 21, and the welding method can further improve the stability of the first heat exchange tube 3 on the polarity terminal); 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.

[0094] In order to further improve the stability of the first heat exchange tube 3 on the single battery, Figure 2b As shown, in this embodiment, L-shaped connecting ribs 12 can be added between the first heat exchange tube 3 and the cell body. 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 cell body. The specific connection method can be selected based on the material of the first heat exchange tube 3. For example, in this embodiment, the first heat exchange tube 3 is made of an insulating material, so the L-shaped connecting rib, the first heat exchange tube 3, and the cell body can be fixedly connected using screws. When the first heat exchange tube 3 is made of metal, the L-shaped connecting rib, the first heat exchange tube 3, and the cell body can be fixedly connected using welding.

[0095] like Figure 4 As shown, when a battery module is constructed using the single cell assembly of this embodiment, the first heat exchange pipe 3 of each single cell 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 achieve heat exchange of the battery module based on the two heat exchange channels.

[0096] It should be noted that a connecting pipe section 26 can be connected to the inlet end or the outlet end of the first heat exchange pipe 3. Taking the inlet end as an example, the connecting pipe section 26 of one first heat exchange pipe 3 can be inserted into the outlet end of another first heat exchange pipe 3 to achieve communication between two adjacent first heat exchange pipes 3, and the connection position between the connecting pipe section 26 and the other first heat exchange pipe 3 needs to be sealed, such as Figure 5As shown. It is also possible to connect the connecting pipe sections at the liquid inlet and the liquid outlet of each first heat exchange pipe member 3. For the convenience 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 exchange pipe members 3, the first pipe 27 of one first heat exchange pipe member 3 and the second pipe 28 of the other first heat exchange pipe member 3 are sealed and plugged into each other. Figure 6 .

[0097] The unpacking member 22 of the lower cover of each single cell can also be opened, and the inner cavity of all the single cells can be connected by a hollow member to achieve electrolyte sharing, reduce the differences between the single cells, and optimize the cycle performance of the battery module;

[0098] The unpacking piece 22 of each single cell upper cover can also be opened, and the inner cavities of all single cells can be connected by another hollow component to achieve gas sharing and gas balance, thereby further optimizing the cycle performance of the battery module.

[0099] Example 2

[0100] Different from the first embodiment, the present embodiment has a through hole 24 penetrating the polarity terminal 21, which serves as a functional structure to increase the heat exchange area between the polarity terminal 21 and the heat exchange medium. Figure 7 and Figure 8 As can be seen, in this embodiment, taking one through hole 24 as an example, the cross-sectional area of ​​through hole 24 can be maximized without affecting the conductivity of polarity terminal 21, thereby increasing the heat exchange area and improving the heat exchange effect. In other embodiments, two or more through holes 24 may be provided, specifically, without affecting the conductivity of polarity terminal 21.

[0101] In this embodiment, the central axis of the through hole 24 is parallel to the plane of the upper cover plate 8. In other embodiments, the extension line of the central axis of the through hole 24 may have a certain angle with the upper cover plate 8, and the angle does not need to be equal to 90°.

[0102] In order to further optimize the heat exchange effect, this embodiment can also set four dividing ribs 29 in the through hole 24. The four dividing ribs 29 are evenly distributed along the circumference of the through hole 24, and each dividing rib 29 extends axially along the through hole 24; based on the four dividing ribs 29, the contact area between the heat exchange medium and the polarity terminal 21 can be increased, that is, the heat exchange area is increased, and the heat exchange effect can be effectively improved.

[0103] In some other embodiments, the number and arrangement of the dividing ribs 29 can be adjusted according to the size of the channel, without affecting the circulation of the heat exchange medium.

[0104] The heat exchange device and the coordination relationship between the heat exchange device and the single battery are the same as those in Example 1 and will not be described again here.

[0105] Example 3

[0106] This embodiment is a second type of single cell assembly. Different from the above embodiment, this embodiment adopts a second heat exchange pipe 4 as the heat exchange device 1 .

[0107] Specific as Figure 9 , which is a schematic structural diagram of a single battery assembly according to this embodiment;

[0108] The structure of the single cell 2 in this embodiment is the same as that in the above embodiment, which will not be described in detail here. The following figures take the single cell in embodiment 1 as an example for description.

[0109] Different from the first heat exchange pipe 3 in embodiment 1, the second heat exchange pipe 4 in this embodiment is provided with two second channels 33, specifically as follows: Figure 9 and Figure 10a As shown, it includes a second tube body 41, in which a first channel 32 and two second channels 33 are provided; the two second channels 33 correspond one-to-one to the polarity terminals 21 of the single battery 2; that is, in this embodiment, the functional structure of the two polarity terminals 21 are both located in the same first channel 32.

[0110] In this embodiment, sealing plates may be added at both ends of the first channel 32 , and holes may be opened in the sealing plates to serve as the inlet and outlet ends of the second heat exchange pipe 4 , respectively.

[0111] The second heat exchange tube 4 is disposed on the top of the single battery 2 . Each polarity terminal 21 is inserted into the corresponding second channel 33 , and the electrical connection portion 211 of the polarity terminal 21 extends out of the second channel 33 .

[0112] It should be noted that, unlike the first heat exchange tube 3, the second heat exchange tube 4 can easily contact the polarity terminals 21 of different polarities of the same single battery 2 at the same time. Therefore, the second heat exchange tube 4 must be insulated from the polarity terminals 21 to prevent two polarity terminals 21 of different polarities from being connected through the second heat exchange tube 4, causing a short circuit; when the second heat exchange tube 4 is insulated from the polarity terminal 21, the polarity terminal 21 cannot be electrically connected to the top of the single battery 2 through the second heat exchange tube 4.

[0113] The insulation between the second heat exchange pipe 4 and the polarity terminal 21 can be achieved in the following manner:

[0114] 1. The second heat exchange pipe 4 is made of insulating material to achieve insulation between the second heat exchange pipe 4 and the polarity terminal 21;

[0115] 2. Use a non-insulated second heat exchange tube 4 and add an insulating sealing gasket between the polarity terminal 21 and the second heat exchange tube 4. Insulate the tube wall of the second heat exchange tube 4, such as spraying insulating paint or wrapping it with insulating film. For safety reasons, you can combine the above methods and use multiple insulation methods to avoid short circuits.

[0116] This embodiment also uses the second heat exchange pipe 4 of insulating medium to achieve insulation between the second heat exchange pipe 4 and the polarity terminal 21. Figure 10a As shown, the sealing method between each polarity terminal 21 and the two ports of the second channel 33 is the same as that in embodiment 1, and will not be repeated here.

[0117] In order to improve the stability of the second heat exchange pipe 4 on the single cell, this embodiment can adopt a method similar to that of embodiment 1, that is, an L-shaped connecting rib is added between the second heat exchange pipe 4 and the single cell cylinder 13, the horizontal plate of the L-shaped connecting rib is fixedly connected to the second heat exchange pipe 4, and the vertical plate of the L-shaped connecting rib is fixedly connected to the single cell cylinder 13. This embodiment can also adopt a U-shaped connecting rib 14, such as Figure 10b As shown, the U-shaped connecting rib is inverted onto the second heat exchange pipe 4, and the two side edges of the U-shaped connecting rib are fixedly connected to the opposite side walls of the single cell barrel. The specific connection method can be selected based on the material of the second heat exchange pipe 4. For example, in this embodiment, the second heat exchange pipe 4 is made of an insulating material, so the U-shaped connecting rib and the single cell barrel can be fixedly connected using screws. If the second heat exchange pipe 4 is made of metal, the U-shaped connecting rib and the single cell barrel can be fixedly connected using welding.

[0118] In addition, unlike Example 1, in this embodiment, after the second heat exchange pipe 4 is arranged on the top of the single cell, its projection basically covers the upper cover of the single cell. If the explosion venting part (the explosion venting part may also be referred to as the explosion venting port, explosion-proof part, explosion-proof port, etc.) is arranged on the upper cover of the single cell, and the gap between the second heat exchange pipe 4 and the upper cover is too small or even does not exist, the thermal runaway flue gas may not be removed in time under the obstruction of the second heat exchange pipe 4, posing a certain safety hazard. In this embodiment, such problems can be solved by the following two solutions:

[0119] Solution 1: Adjust the position of the explosion vent so that it avoids the second heat exchange pipe 4. For example, the explosion vent can be set on the lower cover plate.

[0120] Option 2: If Figure 11 As shown, another avoidance channel perpendicular to the first channel is opened in the second heat exchange pipe member; the avoidance channel corresponds to the explosion relief portion 9 of the upper cover plate; an explosion relief branch pipe 10 is provided on the upper cover plate 8, one end of the explosion relief branch pipe 10 is sealedly connected to the upper cover plate area around the explosion relief portion 9, and the other end passes through the avoidance channel and extends out;

[0121] Similarly, if the liquid injection port 11 is located below the second heat exchange pipe 4, it will be inconvenient to inject liquid. Therefore, the liquid injection port 11 should also be set away from the second heat exchange pipe 4 and can be set at the edge of the upper cover plate, such as Figure 11 In addition, in this embodiment, due to the obstruction of the second heat exchange pipe, it is not convenient to set the unpacking piece on the upper cover plate.

[0122] Similar to Example 1, when the battery module is constructed using the single cells of this embodiment, the second heat exchange pipes 4 of each single cell can be connected, such as Figure 12 As shown (the specific connection method can be connected to the first heat exchange pipe 3 in Example 1), a heat exchange channel is formed at the top of the battery module, and heat exchange of the battery module is achieved through the heat exchange channel. The packaging piece of the lower cover of each single battery can be opened, and the inner cavity of all single batteries can be connected through a hollow component to achieve electrolyte sharing, reduce the differences between single batteries, and optimize the cycle performance of the battery module.

[0123] Example 4

[0124] This embodiment is a third type of single cell assembly. Different from the first embodiment, this embodiment uses two third heat exchange tubes 5 as the heat exchange device 1 . The two third heat exchange tubes 5 correspond one-to-one to the two polarity terminals 21 of the single cell 2 .

[0125] Specific as Figure 13 and Figure 14 As shown,

[0126] in Figure 13 The single battery 2 shown is the same as that in the above embodiment and will not be described again here.

[0127] The third heat exchange tube 5 in this embodiment is a half tube. Here, the half tube can be understood as dividing the entire tube into two halves along the axial direction, and each half is a half tube.

[0128] As above, since the upper cover plate of this embodiment is a rectangular plate, for the sake of structural regularity, the third heat exchange pipe 5 adopts a half pipe with a rectangular cross section, and an avoidance hole 52 is opened on the pipe wall of the third heat exchange pipe 5 (see FIG. Figure 14 ), for the electrical connection portion 211 of the polarity terminal 21 to extend.

[0129] When securing the third heat exchange pipe 5 to the upper cover, it needs to be buckled onto the upper cover and sealed securely to the upper cover. The space between the third heat exchange pipe 5 and the upper cover serves as a heat exchange medium flow chamber. The functional 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 through the avoidance hole 52, and the polarity terminal 21 and the avoidance hole 52 are sealed. Sealing plates 53 can be secured to the two opposing open ends of the half-tube, with openings formed in the sealing plate 53 serving as the inlet and outlet.

[0130] Compared with the first heat exchange pipe 3 and the second heat exchange pipe 4, the heat exchange medium in the third heat exchange pipe 5 can also directly contact with the upper cover plate and directly act on the upper cover plate, thereby achieving a better heat exchange effect.

[0131] It should be noted that:

[0132] 1. Because the polarity terminal 21 of the present invention is in direct contact with the heat exchange medium, the ideal heat exchange medium should possess excellent insulation, high specific heat capacity and thermal conductivity, good flame retardancy, low cost, suitable operating temperature, long life, and be non-corrosive. In the present invention, the insulating heat exchange medium is a common insulating heat exchange medium in the prior art, including, but not limited to, insulating oil and fluorinated liquid.

[0133] 2. If the third heat exchange tube 5 contacts the polarity terminal 21 and is in direct contact with the upper cover plate, and the third heat exchange tube 5 is conductive, the positive and negative polarity terminals 21 of the same single battery 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 an insulating material. If a non-insulating material is used, an insulating seal 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 it with insulating film. To be on the safe side, a combination of the above methods can be used to overcome this problem.

[0134] In this embodiment, a third heat exchange tube 5 made of insulating material is selected, and two third heat exchange tubes 5 are respectively buckled on the upper cover area where the two polarity terminals 21 are located. In order to ensure that the electrical connection portion 211 of the polarity terminal 21 can smoothly pass through the avoidance hole 52 on the third heat exchange tube 5, the orthographic projection area of ​​the avoidance hole 52 in the xy plane needs to be slightly larger than the orthographic projection area of ​​the electrical connection portion 211 of the corresponding polarity terminal 21 in the xy plane, and 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; to ensure that the electrical connection portion 211 of the corresponding polarity terminal 21 can smoothly pass through the corresponding avoidance hole 52.

[0135] Typically, the shape of the avoidance hole 52 matches the cross-sectional shape of the electrical connection portion 211 of the polarity terminal 21. If the avoidance hole 52 is a round hole and the cross-sectional shape of the electrical connection portion 211 of the polarity terminal 21 is circular, then the diameter of the avoidance hole 52 needs to be slightly larger than the outer diameter of the electrical connection portion 211 of the polarity terminal 21. If the avoidance hole 52 is a square hole and the cross-sectional shape of the electrical connection portion 211 of the polarity terminal 21 is square, then the area of ​​the avoidance 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 avoidance hole 52 does not need to match the cross-sectional shape of the electrical connection portion 211 of the polarity terminal 21. It is only necessary to ensure that the electrical connection portion 211 of the polarity terminal 21 can smoothly pass through the corresponding avoidance hole 52 and that a seal can be achieved between the two.

[0136] When the heat exchange medium is liquid, the sealing performance of the third heat exchange pipe 5 is particularly important. 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 avoidance hole 52, the area of ​​the third heat exchange tube 5 surrounding the avoidance hole 52 is sealed and pressed against the stepped surface. Furthermore, an insulating sealant layer 7 can be laid on the stepped surface, and the area of ​​the third heat exchange tube 5 surrounding the avoidance hole 52 is pressed against the insulating sealant layer 7. Simultaneously, the insulating sealant penetrates the gap between the avoidance hole 52 and the polarity terminal 21, thereby achieving a seal between the polarity terminal 21 and the avoidance hole 52. In other embodiments, an O-ring 23 can be provided between the polarity terminal 21 and the avoidance hole 52 to achieve a seal between the two.

[0137] 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 surface of the third heat exchange pipe 5. The annular protrusion is inserted into the annular groove, and sealant is applied to the matching position to achieve sealing and fixation of the third heat exchange pipe 5 and the upper cover plate.

[0138] In some other embodiments, a third heat exchange pipe 5 made of metal can be selected. In order to ensure the insulation between the polarity terminal 21 and the avoidance hole 52, an O-shaped insulating sealing ring can be added between the two to achieve insulation and sealing between the two; the third heat exchange pipe 5 and the upper cover plate can be sealed and fixed by welding.

[0139] Similar to Example 1, when constructing a battery module using the single cells of this embodiment, the third heat exchange pipe 5 of each single 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 to achieve heat exchange of the battery module based on the two heat exchange channels.

[0140] It should be noted that a connecting pipe section 26 can be connected to the inlet or outlet end of the third heat exchange pipe 5. Taking the inlet end as an example, the connecting pipe section 26 of one third heat exchange pipe 5 can be inserted into the outlet end of another third heat exchange pipe 5 to achieve communication between two adjacent third heat exchange pipes 5, and the connection position between the connecting pipe section 26 and the other third heat exchange pipe 5 needs to be sealed, such as Figure 16 As shown. It is also possible to connect the connecting pipe sections at the liquid inlet and liquid outlet of each third heat exchange pipe 5. For the convenience 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 exchange pipes 5, the first pipe 27 of one third heat exchange pipe 5 and the second pipe 28 of the other third heat exchange pipe 5 are sealed and plugged into each other. Figure 17 .

[0141] The unpacking piece on each cell's lower cover can be opened, and the inner cavities of all cells can be connected using a hollow component, enabling electrolyte sharing, reducing differences between cells, and optimizing the battery module's cycling performance. The unpacking piece on each cell's upper cover can also be opened, and the inner cavities of all cells can be connected using another hollow component, enabling gas sharing and achieving gas balance, further optimizing the battery module's cycling performance.

[0142] Example 5

[0143] This embodiment is a fourth type of single cell assembly. Different from the fourth embodiment, this embodiment uses a fourth heat exchange pipe 6 as a heat exchange device. The specific structure is as follows: Figure 18 shown.

[0144] The structure of the single battery 2 in this embodiment is the same as that in the above embodiment, and will not be described again here.

[0145] Different from the third heat exchange tube 5 in the fourth embodiment, the fourth heat exchange tube 6 in this embodiment is provided with two avoidance holes 52 on its tube wall. The two avoidance holes 52 correspond to the two polarity terminals 21 of the single battery cells respectively.

[0146] In this embodiment, the functional structures of the two polarity terminals 21 are both located in the same heat exchange medium flow cavity. In this embodiment, sealing plates can be added at both ends of the fourth heat exchange pipe 6, and holes are opened in the sealing plates to serve as the inlet and outlet of the fourth heat exchange pipe 6 respectively.

[0147] This embodiment uses a fourth heat exchange tube 6 made of insulating material. The sealing method between each polarity terminal 21 and the avoidance hole 52 is the same as that in Example 4 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 that in Example 4 and will not be repeated here.

[0148] This embodiment can adopt a structure similar to that of Example 3, adjusting the explosion vent (or adding an explosion vent branch) and the position of the liquid injection port so that the fourth heat exchange pipe 6 does not affect the normal use of the explosion vent and the liquid injection port. Similarly, due to the obstruction of the fourth heat exchange pipe 6, it is not convenient to install the opening device on the upper cover.

[0149] Similar to the above embodiment, when constructing a battery module using the single cells of this embodiment, the fourth heat exchange pipes 6 of the single cells can be connected to form a heat exchange channel on the top of the battery module to achieve heat exchange of the battery module based on the heat exchange channel.

[0150] The unpacking piece of the lower cover of each single cell can be opened, and the inner cavity of all single cells can be connected by a hollow component to achieve electrolyte sharing, reduce the differences between each single cell, and optimize the cycle performance of the battery module.

Claims

1. A single battery assembly, characterized in that: Including single battery and heat exchange device; A functional structure is provided on the polarity terminal of the single battery, which is used to increase the heat exchange area of ​​the polarity terminal; The heat exchange device is located on the top of the single battery, and the inner cavity of the heat exchange device serves as the heat exchange medium flow cavity; The polarity terminals of the single battery pass through the heat exchange device, and the side walls of the extreme terminals are sealed from the heat exchange device; the part of the polarity terminal with a functional structure is located in the heat exchange medium flow cavity and is in direct contact with the heat exchange medium; the other part of the polarity terminal structure is located outside the heat exchange device and serves as an electrical connection part.

2. The single battery assembly according to claim 1, characterized in that: The functional structure is n first annular grooves, where n is an integer greater than or equal to 1; Each first annular groove extends circumferentially along a side surface of the polarity terminal, and the n first annular grooves are arranged along a height direction of the polarity terminal.

3. The single battery assembly according to claim 1, wherein: The functional structure is at least one through hole provided on the polarity terminal, and the through hole penetrates the polarity terminal along the x direction.

4. The single battery assembly according to claim 3, characterized in that: The inner wall of the through hole is provided with a plurality of dividing ribs; the plurality of dividing ribs are evenly distributed along the circumference of the through hole, and each dividing rib extends along the axial direction of the through hole.

5. The single cell assembly according to any one of claims 1 to 4, characterized in that: The heat exchange device includes two first heat exchange pipes, each of which includes a first pipe body, and a first channel and a second channel are provided in the first pipe body; The inner cavity of the first channel serves as a heat exchange medium flow cavity; the second channel is perpendicular to the first channel and is connected to the first channel; The two polarity terminals of the single battery correspond one to one with the two first heat exchange tubes; the portion of each polarity terminal provided with the functional structure is inserted into the first channel of the corresponding first heat exchange tube through the second channel, and the other portion of the structure extends out of the second channel to serve as an electrical connection portion; The two ports of the second channel are sealed with the polarity terminals.

6. The single cell battery assembly according to any one of claims 1 to 4, characterized in that: The heat exchange device includes a second heat exchange pipe, the second heat exchange pipe includes a second pipe body, and the second pipe body is provided with a first channel and two second channels; The inner cavity of the first channel serves as a heat exchange medium flow cavity; the second channel is perpendicular to the first channel and is connected to the first channel; The two polarity terminals of the single battery correspond to the two second channels one by one; the portion of each polarity terminal provided with a functional structure 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 to serve as an electrical connection portion; The two ports of the second channel are sealed with the polarity terminals.

7. The single cell battery assembly according to any one of claims 1 to 4, characterized in that: The heat exchange device includes two third heat exchange pipes, and the two third heat exchange pipes correspond one to one with the two polarity terminals of the single battery; The third heat exchange pipe is a half pipe with an avoidance hole formed on the wall of the half pipe; the third heat exchange pipe is buckled and sealed on the upper cover of the single cell; the space formed between the third heat exchange pipe and the upper cover of the single cell serves as a heat exchange medium flow chamber; The functional structure of the polarity terminal of the single battery is located in the heat exchange medium flow cavity, and the other part of the structure extends out of the avoidance hole corresponding to the third heat exchange pipe to serve as the electrical connection part; The polarity terminals and the corresponding avoidance holes are sealed.

8. The single cell battery assembly according to any one of claims 1 to 4, characterized in that: The heat exchange device includes a fourth heat exchange pipe, which is a half pipe. Two avoidance holes are opened on the wall of the half pipe. The two avoidance holes correspond to the two polarity terminals of the single battery one by one. The fourth heat exchange pipe is buckled and sealed on the upper cover of the single cell; the space formed between the fourth heat exchange pipe and the upper cover of the single cell serves as a heat exchange medium flow cavity; The functional structure of the single battery polarity terminal is located in the heat exchange medium flow cavity, and the other part of the structure extends out of the corresponding avoidance hole to serve as the electrical connection part; The polarity terminals and the corresponding avoidance holes are sealed.

9. The single battery assembly according to claim 1, characterized in that: The heat exchange device is made of electrically insulating material.

10. The single battery assembly according to claim 1, characterized in that: An opening piece is provided on the lower cover of the single battery.

11. The single battery assembly according to claim 1, characterized in that: The inlet end and / or the outlet end of the heat exchange device are connected with a connecting pipe section.

12. A battery module, characterized in that: The invention comprises a single cell assembly according to any one of claims 1 to 11; the heat exchange devices of adjacent single cell assemblies are interconnected via a connecting pipe section.

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