Pole component, cover plate assembly, battery monomer and battery module

Abstract

The invention relates to the technical field of batteries, in particular to a pole assembly, a cover plate assembly, a battery monomer and a battery module. The pole assembly comprises a pole, the pole comprises a pole body and a through hole penetrating through the pole body, the through hole penetrates through the pole body in the first direction, the distance between the top wall of the through hole and the upper surface of the pole body is larger than 0, and the distance between the top wall of the through hole and the upper surface of the pole body is larger than 0. The distance between the bottom wall of the through hole and the lower surface of the pole body is greater than 0; the cooling pipe is arranged in the through hole in a penetrating mode, and a cooling medium is contained in the cooling pipe; the first direction is parallel to the width direction of the cover plate comprising the pole assembly. The problem that the temperature is too high during rate charging and discharging of the battery cell can be effectively relieved, and the cooling efficiency of the pole can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a pole assembly, a cover plate assembly, a battery cell and a battery module. Background Art

[0002] In a battery, the pole refers to the part where the positive and negative poles inside the battery are connected to the external circuit. The pole is usually made of metal. When the battery is charged and discharged at a high rate, the large current will cause the battery cell to generate high temperature, especially the structural parts of the battery cover, including the pole, pole ear and other parts. The highest temperature of the battery cell appears in this area. Even if the size of this part of the structural parts is increased, it will not have a good effect, because the volume / weight of this part of the structural parts is too small and the specific heat capacity is small. If you want to completely reduce the temperature of the structural parts, you must find a way to take the generated heat out. If the heat cannot be dissipated in time, it will greatly shorten the life of the battery and may even cause serious safety hazards.

[0003] In the related art, a water cooling structure is set on the large surface, bottom surface or side surface of the battery cell to dissipate heat, so as to take out the temperature of the electrode group and keep the electrode group at a low temperature, and then the high temperature of the structural parts is transferred to the electrode group in the low temperature area. However, these methods are usually only applicable to the case where the charge and discharge rate is not particularly large. At a larger rate, such as above 6C, the high temperature generated on the structural parts will not have time to transfer heat to the electrode group, and the temperature of the structural parts will still remain high. Therefore, how to quickly dissipate the heat generated by the structural parts is a technical problem that needs to be solved in this field. Summary of the invention

[0004] In view of this, the present invention aims to solve one of the technical problems in the related art to at least a certain extent. To this end, the present invention provides a pole assembly, a cover plate assembly, a battery cell and a battery module, which can alleviate the excessive temperature of the battery cell during charging and discharging, and improve the pole cooling efficiency.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] According to a first aspect of the present application, the present application provides a pole assembly, the pole assembly comprising:

[0007] A pole, the pole comprising a pole body and a through hole penetrating the pole body, the through hole penetrating the pole body along a first direction, a distance between a top wall of the through hole and an upper surface of the pole body being greater than 0, and a distance between a bottom wall of the through hole and a lower surface of the pole body being greater than 0;

[0008] A cooling pipe, the cooling pipe is inserted into the through hole, and a cooling medium is contained in the cooling pipe;

[0009] The first direction is parallel to the width direction of the cover plate including the pole assembly.

[0010] In addition, the pole assembly according to the present application may further have the following additional technical features:

[0011] In some embodiments, the distance between the top wall of the through hole and the upper surface of the pole body is a, and the a satisfies: 2 mm ≤ a ≤ 5 mm.

[0012] In some embodiments, the distance between the bottom wall of the through hole and the lower surface of the pole body is b, and the b satisfies: 1.5 mm ≤ b ≤ 5 mm.

[0013] In some embodiments, a gap space is provided between the inner wall of the through hole and the outer wall of the cooling tube, a filling medium is provided in the gap space, and the thermal conductivity of the filling medium is ≥ 400 W / (m·K).

[0014] In some embodiments, the filling medium includes at least one of carbon nanotube glue or silver glue.

[0015] In some embodiments, the pole includes an upper pole and a lower pole. The pole body of the lower pole includes a columnar portion and a plate portion. The through hole is provided in the columnar portion; the plate portion is disposed around the bottom edge of the columnar portion and is connected to the columnar portion, and the size of the outer contour of the plate portion is larger than the size of the outer contour of the columnar portion; the upper pole is connected to the outside of the columnar portion.

[0016] In some embodiments, the upper pole is provided with a groove corresponding to the through hole. The opening of the groove faces downward, and the groove is provided on both end faces of the inlet and outlet of the through hole.

[0017] According to a second aspect of the present application, the present application provides a cover assembly, and the cover assembly includes:

[0018] A cover plate provided with a pole hole;

[0019] The aforementioned pole assembly, at least a part of the pole in the pole assembly penetrates through the pole hole, and the through hole in the pole and the cooling tube penetrating through the through hole are both located above the upper surface of the cover plate.

[0020] In some of these embodiments, the cover assembly further includes a first plastic part, a second plastic part, and a seal; the first plastic part, the second plastic part, and the seal are all provided with pole post holes for the pole post to pass through; the first plastic part is arranged on one side of the cover along the thickness direction, and the second plastic part is arranged on the other side of the cover along the thickness direction; the seal is arranged between the pole post body and the pole post hole and is adapted to seal-connect the pole post and the cover.

[0021] According to the third aspect of the present application, the present application provides a battery cell, which includes:

[0022] a battery core;

[0023] the aforementioned cover assembly, which is arranged at one end or both ends of the battery cell, and the pole post is electrically connected to the battery core.

[0024] According to the fourth aspect of the present application, the present application provides a battery module, which includes a plurality of the aforementioned battery cells;

[0025] The plurality of battery cells are arranged in a row along the first direction;

[0026] The through holes on each of the battery cells are arranged correspondingly, and the cooling pipe sequentially passes through the through holes on each of the battery cells along the first direction.

[0027] Implementing the technical solution of the present invention has at least the following beneficial effects:

[0028] In the embodiment of the present application, the provided pole post assembly includes a cooling pipe. By providing a through hole penetrating the pole post body on the pole post body, the cooling pipe can be passed through the through hole, and the pole post can be dissipated heat by using the cooling medium in the cooling pipe, which can quickly dissipate the heat at the pole post. In the present application, by providing a through hole on the pole post body and installing the cooling pipe in the through hole, the pole post is cooled specifically by the cooling pipe, improving the cooling efficiency of the battery, quickly taking away the heat generated by the structural member, enabling the battery including the pole post assembly to support high-rate charge and discharge, meeting the heat dissipation requirements of high-rate charge and discharge, and being beneficial to improving the service life of the battery.

[0029] In the preferred embodiment of the present application, by making the distance between the top wall of the through hole and the upper surface of the pole post body within an appropriate range and making the distance between the bottom wall of the through hole and the lower surface of the pole post body within an appropriate range, it is possible to avoid the problem that during internal welding, the penetration depth is easily penetrated into the through hole, causing deformation of the insert block or welding explosion holes, and it is also possible to avoid the problem that the height of the pole post is too high, which is not conducive to capacity improvement, and at the same time, the material consumption of the pole post is large and the cost is increased.

[0030] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings

[0031] Figure 1 The figure shows a schematic structural diagram of a battery module provided by an embodiment of the present invention;

[0032] Figure 2 The figure shows a schematic structural diagram of a cover assembly provided by an embodiment of the present invention;

[0033] Figure 3 The figure shows an exploded view of a cover assembly provided by an embodiment of the present invention;

[0034] Figure 4 The figure shows a front view of a cover assembly provided by an embodiment of the present invention;

[0035] Figure 5 is Figure 4 a schematic diagram of the A-A cross-section in ;

[0036] Figure 6 is Figure 4 a schematic diagram of the B-B cross-section in ;

[0037] Figure 7 is Figure 5 an enlarged schematic diagram of the pole column area in ;

[0038] Figure 8 is Figure 5 an enlarged schematic diagram of the pole column area after assembly with the cooling pipe in ;

[0039] Figure 9 The figure shows a schematic diagram of the actual temperature rise of a battery cell provided by Comparative Example 3 of the present invention;

[0040] Figure 10 The figure shows a schematic diagram of the actual temperature rise of a battery cell provided by Comparative Example 4 of the present invention;

[0041] Figure 11 The figure shows a schematic diagram of the actual temperature rise of a battery cell provided by Embodiment 1 of the present invention.

[0042] Description of the Reference Numerals:

[0043] 10 - Cover assembly;

[0044] 100 - Pole column;

[0045] 101 - Upper pole column; 102 - Lower pole column; 121 - Column body part; 122 - Plate body part; 103 - Pole column body; 104 - Through hole; 105 - Groove; 106 - Cooling pipe; 107 - Filling medium;

[0046] 110 - Cover plate; 111 - Terminal post hole;

[0047] 120 - First plastic part;

[0048] 130 - Second plastic part;

[0049] 140 - Seal;

[0050] 20 - Battery cell;

[0051] 30 - Battery single body;

[0052] 40 - Battery module. Detailed implementation manners

[0053] The following further elaborates the present application in combination with specific embodiments. It should be understood that these embodiments of the present application are only used to illustrate the present application and not to limit the scope of the present application.

[0054] Hereinafter, the implementation manners of the terminal post assembly, cover plate assembly, battery single body, battery module, etc. of the present application specifically disclosed will be described in detail with appropriate reference to the accompanying drawings. However, there may be cases where unnecessary detailed descriptions are omitted. For example, there are cases where detailed descriptions of well-known matters and repeated descriptions of actually identical structures are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter recited in the claims.

[0055] If there is no special description, all the implementation manners and optional implementation manners of the present application can be combined with each other to form a new technical solution.

[0056] If there is no special description, all the technical features and optional technical features of the present application can be combined with each other to form a new technical solution.

[0057] As analyzed in the background art, when the battery is charged and discharged at high rates, the temperature of the structural parts including the terminal post is relatively high, and it is difficult for the heat to dissipate. In the case of high rates such as above 6C, the high temperature generated on the structural parts simply has no time to transfer to the electrode group, and the temperature of the structural parts will still remain high. Therefore, the key to solving this problem is to find a way to quickly take away the heat generated by the structural parts. However, the prior art lacks a technical solution for effectively cooling the terminal post. Therefore, the present invention provides a terminal post assembly to solve the problem of excessive temperature during the rate charge and discharge of the battery cell. In view of this, the present application provides a terminal post assembly, as well as a cover plate assembly, a battery single body, and a battery module including the terminal post assembly. The following will describe the present application in detail.

[0058] Figure 1 It is a structural schematic diagram of a battery module. Figure 2It is a schematic structural diagram of the cover assembly, Figure 3 and is an exploded view of the cover assembly; Figure 4 is a front view of the cover assembly; Figure 5 is Figure 4 a schematic diagram of the A-A cross-section in;

[0059] Figure 6 is Figure 4 a schematic diagram of the B-B cross-section in; Figure 7 is Figure 5 an enlarged schematic diagram of the terminal post area in; Figure 8 is Figure 5 an enlarged schematic diagram of the terminal post area after being assembled with the cooling pipe in.

[0060] In the embodiment of the present application, by changing the cooling method of the terminal post and performing targeted cooling on the terminal post, the heat generated by the structural member can be quickly taken away, thereby alleviating the problem of excessive temperature during the high-rate charge and discharge of the battery cell, and improving the cooling efficiency.

[0061] The solution of the embodiment of the present application may but is not limited to include the battery cell 30 or the battery module 40 or the battery pack, and may also be applied to an electrical device including the battery cell 30 and the battery module 40 or the battery pack. By changing the cooling method of the terminal post 100, the battery terminal post assembly can support high-rate charge and discharge, thereby improving the service life of the battery cell 30 and the battery module 40 or the battery pack.

[0062] When applying the battery cell 30 and the battery module 40 or the battery pack including the terminal post assembly of the present application to an electrical device, the electrical device is a device that uses electrical energy as an energy source and realizes corresponding functions by consuming electrical energy. Exemplarily, the electrical device may be but is not limited to a vehicle, a ship, an aircraft, or an energy storage system, etc., and the vehicle may be, for example, an electric vehicle, an electric car, an electric motorcycle, etc.

[0063] In the embodiment of the present application, the battery pack may include a box body and a battery module 40 arranged in the box body. The box body refers to a structure having an accommodation space, and the battery module 40 is accommodated in the box body. The number of battery modules 40 is one or more. One or more battery modules 40 are arranged in the box body. The type of the box body is not limited. The box body may be a frame-shaped box body, a disk-shaped box body, or a box-shaped box body, etc.

[0064] Refer to Figure 1As shown, in some embodiments, the present application provides a battery module 40, which includes a plurality of battery cells 30, that is, the number of battery cells 30 can be multiple. The multiple battery cells 30 can be connected in series, parallel, or in a combined series-parallel manner. The combined series-parallel connection means that there are both series and parallel connections among the multiple battery cells 30. The multiple battery cells 30 can be directly connected in series, parallel, or in a combined series-parallel manner, and then the battery module 40 formed by the multiple battery cells 30 is placed in a battery box. The battery module 40 can also include other structures. For example, the battery module 40 can also include a busbar component for realizing the electrical connection among the multiple battery cells 30.

[0065] The battery cell 30 refers to the basic unit that can realize the mutual conversion between chemical energy and electrical energy.

[0066] In the embodiments of the present application, the battery cell 30 can be a secondary battery. A secondary battery refers to a battery cell 30 that can be activated by charging after discharging to continue use. The embodiments of the present application do not limit the specific type of the battery cell 30. The battery cell 30 can be, for example, a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium-metal battery, a sodium-metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-cadmium battery, etc., and the present application does not limit this.

[0067] Optionally, the battery module 40 is formed by arranging a plurality of battery cells 30 in a set direction, such as the first direction. The multiple battery cells 30 are connected together in series or parallel to form a battery module 40. Series connection means connecting the positive and negative electrodes of the battery cells 30 in sequence to increase the voltage of the battery module 40; while parallel connection means connecting the positive and positive electrodes and the negative and negative electrodes of the battery cells 30 together to increase the current capacity of the battery module 40. By different series-parallel connection methods, battery modules 40 with different voltages and current capacities can be formed to meet different power requirements.

[0068] It should be noted that in this article, the first direction can be understood as the thickness direction of the battery cell 30, or can be understood as the width direction of the cover plate 110 in the battery cell 30.

[0069] In the battery module 40 of the present application, the multiple battery cells 30 are arranged along the first direction.

[0070] Reference Figure 1-2 As shown, in some embodiments, the present application provides a battery cell 30, which includes a housing, a battery core 20 disposed in the housing, and a cover plate assembly 10 hermetically connected to the housing. The cover plate assembly 10 in the battery cell 30 can be disposed at one end or both ends of the battery cell 30, and the terminal post 100 in the cover plate assembly 10 is electrically connected to the battery core 20.

[0071] The above-mentioned housing is provided with a receiving cavity. The battery cell 20 is disposed in the receiving cavity. The cover assembly 10 can be disposed at one end of the housing. For example, if the cover assembly 10 is disposed on the top of the housing, the cover assembly 10 is used to close the receiving cavity, and the cover assembly 10 and the housing can protect the battery cell 20.

[0072] Optionally, the above-mentioned housing is of a square structure or other shapes; the housing can be made of materials such as aluminum, aluminum alloy or plastic, etc., and no limitation is made thereto.

[0073] Optionally, the above-mentioned battery cell 20 includes a positive electrode, a negative electrode and a separator. The separator is disposed between the positive electrode and the negative electrode. The specific structure of the battery cell 20 or the materials of the positive and negative electrodes and the separator in the embodiments of the present application are not limited.

[0074] Reference Figure 2-8 As shown, in some embodiments, the present application provides a cover assembly 10. The cover assembly 10 includes a cover plate 110 and a pole column assembly. The cover plate 110 is provided with a pole column hole 111. The pole column hole 111 can penetrate the upper and lower surfaces of the cover plate 110. The pole column 100 in the pole column assembly is matched with the pole column hole 111. For example, at least a part of the pole column 100 in the pole column assembly is disposed in the pole column hole 111.

[0075] The above-mentioned cover plate 110 includes a first side surface and a second side surface which are oppositely arranged. The first side surface can be the upper surface, and the second side surface can be the lower surface. The two ends of the pole column hole 111 respectively penetrate the first side surface and the second side surface.

[0076] It should be noted that in practical applications, the first side surface is usually the outer side surface of the cover plate 110, that is, the side of the cover plate 110 away from the battery cell 20, and the second side surface is usually the inner side surface of the cover plate 110, that is, the side of the cover plate 110 close to the battery cell 20.

[0077] In some embodiments, the cover assembly 10 may further include a first plastic part 120, a second plastic part 130 and a sealing part 140; that is, the cover assembly 10 may include a cover plate 110, a first plastic part 120, a second plastic part 130, a sealing part 140 and a pole column assembly.

[0078] Optionally, the above-mentioned cover plate 110 is a bright aluminum plate.

[0079] The specific structures and connection settings of the components of the cover assembly 10 will be further described below.

[0080] Reference Figure 2-8As shown, in some embodiments, the present application provides a terminal assembly, which includes a terminal 100 and a cooling tube 106. Among them, the terminal 100 includes a terminal body 103 and a through hole 104 penetrating the terminal body 103. The through hole 104 penetrates the terminal body 103 along a first direction. The distance between the top wall of the through hole 104 and the upper surface of the terminal body 103 is greater than 0, and the distance between the bottom wall of the through hole 104 and the lower surface of the terminal body 103 is greater than 0. The cooling tube 106 is disposed in the through hole 104, and a cooling medium is accommodated in the cooling tube 106. The first direction is parallel to the width direction of the cover plate 110 including the terminal assembly.

[0081] In the present application, the terminal 100 is provided with a through hole 104, which penetrates the terminal body 103 along a first direction. This first direction is parallel to the width direction of the cover plate 110, that is, the thickness direction of the battery cell 20. At least a part of the cooling tube 106 can be disposed in the through hole 104, and a cooling medium can be accommodated in the cooling tube 106.

[0082] Thus, by providing the through hole 104 in the terminal 100 and installing the cooling tube 106 in the through hole 104, heat transfer can occur between the terminal 100, the cooling tube 106, and the cooling medium. To achieve the cooling of the terminal 100, the cooling medium should be maintained at a relatively low temperature. The heat generated by the terminal 100 is transferred to the cooling medium, thereby quickly dissipating the heat at the terminal 100. In view of the problem that more heat is generated at the terminal 100 and it is not easy to dissipate, the present application specifically cools the terminal 100 by disposing the cooling tube 106 in the through hole 104 of the terminal 100, so that the terminal 100 is quickly cooled, improving the cooling efficiency of the battery. The heat generated by the structural member can be quickly taken away, enabling the battery including the terminal assembly to support high-rate charge and discharge and meet the heat dissipation requirements of high-rate charge and discharge, which is beneficial to improving the service life of the battery.

[0083] Optionally, the cooling medium in the cooling tube 106 can be a liquid material. The cooling medium being a liquid material means that the cooling medium remains in a liquid state throughout the heat dissipation process. Using a liquid material as the cooling medium belongs to the liquid cooling heat dissipation method. By keeping the cooling medium within a relatively low temperature range, the heat generated by the terminal 100 is absorbed. The liquid cooling medium can be water, oil, or other liquids with a relatively large specific heat capacity. Preferably, the present application uses water with a relatively low cost as the cooling medium.

[0084] In addition, in other embodiments, the cooling medium can also be a gaseous material, a phase change material, etc., which is not limited herein.

[0085] Optionally, a cooling medium source, such as a water source, may be provided in the battery module 40. A cooling medium inlet and a cooling medium outlet may be respectively provided at both ends of the cooling pipe 106. The cooling medium inlet is used for the flowing cooling medium to flow into the cooling pipe 106, and the cooling medium outlet is used for the flowing cooling medium to flow out of the cooling pipe 106. The cooling medium continuously flows in the cooling pipe 106, and the temperature difference between the cooling medium and the pole column 100 always exists, so the heat transfer rate will not decrease, and the cooling effect of the flowing cooling medium on the pole column 100 is better. Specifically, when in use, taking water as the cooling medium as an example, the cooling medium inlets and the cooling medium outlets of each cooling pipe 106 are respectively communicated with the water source, so that the cooling of the pole column 100 by the cooling water (or circulating water) can be realized.

[0086] In the present application, there is a certain distance between the top wall of the through hole 104 and the upper surface of the pole column body 103, and there is a certain distance between the bottom wall of the through hole 104 and the lower surface of the pole column body 103.

[0087] In some embodiments, the distance between the top wall of the through hole 104 and the upper surface of the pole column body 103 is a (refer to the a marked in Figure 7 ). It should be understood that if the distance a is too small, that is, the distance between the top wall of the through hole 104 and the upper surface of the pole column body 103 is too small, it will cause the penetration depth of the bar welding on the upper surface of the pole column 100 to easily reach the through hole 104, resulting in the deformation of the insert block and the welding explosion hole, reducing the strength of the pole column 100. If the distance a is too large, that is, the distance between the top wall of the through hole 104 and the upper surface of the pole column body 103 is too large, it will cause the height of the pole column 100 to be too high, which is not conducive to the improvement of the capacity, and at the same time, the material consumption of the pole column 100 is too large, resulting in too high cost.

[0088] Therefore, in the embodiments of the present application, the distance a is limited within the following range: 2 mm ≤ a ≤ 5 mm. In this way, the above problems caused by the distance a being too large or too small can be effectively avoided.

[0089] In some embodiments, the distance a can specifically be selected as 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc.

[0090] In some embodiments, the distance between the bottom wall of the through hole 104 and the lower surface of the pole column body 103 is b (refer to Figure 7As marked in b). It should be understood that if the distance b is too small, that is, the distance between the bottom wall of the through hole 104 and the lower surface of the pole column body 103 is too small, it will cause the penetration depth to easily penetrate into the through hole 104 when internally welding the tab or connecting piece, resulting in the deformation of the insert block and the explosion of the welding hole. If the distance b is too large, that is, the distance between the bottom wall of the through hole 104 and the lower surface of the pole column body 103 is too large, it will cause the height of the pole column 100 to be too high, which is not conducive to the improvement of capacity. At the same time, the material consumption of the pole column 100 is relatively large, resulting in a relatively high cost.

[0091] Therefore, in the embodiments of the present application, the distance b is limited within the following range: 1.5 mm ≤ b ≤ 5 mm. In this way, the above problems caused by the distance b being too large or too small can be effectively avoided.

[0092] In some embodiments, the distance b can specifically be selected as 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc.

[0093] Thus, by making the distance between the top wall of the through hole 104 and the upper surface of the pole column body 103 within the above suitable range and making the distance between the bottom wall of the through hole 104 and the lower surface of the pole column body 103 within the above suitable range, it is possible to avoid the problem that the penetration depth easily penetrates into the through hole 104 during internal welding, resulting in the deformation of the insert block and the explosion of the welding hole. It is also possible to avoid the problem that the height of the pole column 100 is too high, which is not conducive to capacity improvement, and at the same time, the material consumption of the pole column 100 is large and the cost is increased.

[0094] In the present application, the cooling pipe 106 passes through the through hole 104, but the cooling pipe 106 needs to be in insulating contact with the pole column body 103. Therefore, in some embodiments, a gap space is provided between the inner wall of the through hole 104 and the outer wall of the cooling pipe 106, and a filling medium 107 is provided in the gap space, and the thermal conductivity of the filling medium 107 ≥ 400 W / (m·K).

[0095] The outer diameter of the above-mentioned cooling pipe 106 is smaller than the size of the through hole 104, so that there is a gap space between the inner wall of the through hole 104 and the outer wall of the cooling pipe 106. A filling medium 107 is arranged in this gap space. On the one hand, it can play an insulating role, and on the other hand, it can also play a heat-conducting role. The thermal conductivity of the filled filling medium 107 needs to meet not less than 400 W / (m·K). This is because the through hole 104 is arranged in the part of the pole 100 that is internally soft-connected to the battery cell 20. This part will be connected to the soft connection of aluminum material (positive electrode side) or copper material (negative electrode side) by welding or other means. The thermal conductivity of aluminum material is generally 250 W / (m·K), and the thermal conductivity of copper material is generally 400 W / (m·K). Therefore, if the cooling pipe 106 is to play a role in rapid cooling, the high temperature generated by the pole 100 must be transferred to the cooling pipe 106 part quickly and preferentially. This requires the heat to quickly pass through the filling medium 107 and be transferred to the cooling pipe 106. Furthermore, by arranging the filling medium 107 with a thermal conductivity ≥ 400 W / (m·K) between the cooling pipe 106 and the pole body 103, the above requirements can be met, the cooling pipe 106 can play a role in rapid cooling, and the cooling pipe 106 can be in insulated contact with the pole body 103.

[0096] Optionally, the filling medium 107 includes but is not limited to at least one of carbon nanotube glue or silver glue. For example, the filling medium 107 can be selected as carbon nanotube glue, or silver glue, or a combination of carbon nanotube glue and silver glue.

[0097] The above-mentioned carbon nanotube glue and silver glue are both insulating materials with high thermal conductivity. Among them, carbon nanotubes have more excellent thermal conductivity. Therefore, the filling medium 107 in this application is preferably carbon nanotube glue.

[0098] In some embodiments, the pole 100 includes an upper pole 101 and a lower pole 102. The pole body 103 of the lower pole 102 includes a column body part 121 and a plate body part 122. The column body part 121 is provided with a through hole 104; the plate body part 122 is arranged around the bottom edge of the column body part 121 and is connected to the column body part 121. The size of the outer contour of the plate body part 122 is larger than the size of the outer contour of the column body part 121; the upper pole 101 is connected to the outside of the column body part 121.

[0099] In an embodiment of the present application, the terminal post 100 includes an upper terminal post 101 and a lower terminal post 102. The upper terminal post 101 is connected to the lower terminal post 102. The lower terminal post 102 includes a terminal post body 103 and a through hole 104 penetrating the terminal post body 103. Further, the lower terminal post 102 includes a columnar portion 121 and a plate portion 122. At least a part of the columnar portion 121 is usually disposed in the terminal post hole 111 of the cover plate 110. The plate portion 122 is connected to the columnar portion 121, and the plate portion 122 is located inside the cover plate 110 (i.e., the side of the cover plate close to the battery cell). The columnar portion 121 is provided with the above-mentioned through hole 104. In the cover plate assembly 10, the through hole 104 is located outside the cover plate 110 (the through hole 104 is above the upper surface of the cover plate 110), that is, the through hole 104 protrudes from the upper surface of the cover plate 110.

[0100] The above-mentioned plate portion 122 can also be referred to as a base. The plate portion 122 is disposed around the bottom edge of the columnar portion 121 and is connected to the columnar portion 121. The size of the outer contour of the plate portion 122 is larger than the size of the outer contour of the columnar portion 121. The plate portion 122 can be used to connect the tab or the adapter plate.

[0101] Optionally, in the lower terminal post 102, the plate portion 122 and the columnar portion 121 can be integrally formed, that is, the plate portion 122 and the columnar portion 121 can be an integral structure.

[0102] Optionally, the upper terminal post 101 can be disposed outside the columnar portion 121 of the lower terminal post 102, and the size of the upper terminal post 101 is larger than the sizes of the plate portion 122 and the columnar portion 121. For example, the upper terminal post 101 can be provided with an opening that cooperates with the columnar portion 121, and the upper terminal post 101 and the columnar portion 121 can be connected by fitting through the opening.

[0103] Optionally, the upper terminal post 101 and the lower terminal post 102 can be connected by welding, riveting, riveting + welding, etc. By the connection between the upper terminal post 101 and the lower terminal post 102, the various intermediate components in the cover plate assembly 10 can be pressed and fixed.

[0104] It should be noted that in practical applications, the upper surface of the terminal post formed after the upper terminal post 101 and the lower terminal post 102 are connected can be used to connect the bus bar. The lower surface of the terminal post formed after the upper terminal post 101 and the lower terminal post 102 are connected, that is, the lower surface of the plate portion 122 can be used to directly connect the tab of the battery cell 20 (or can also be indirectly connected to the tab of the battery cell through an adapter plate). In this way, the terminal post 100 can realize the electrical connection between the tab of the battery cell 20 and the bus bar.

[0105] In some embodiments, the upper terminal post 101 is provided with a groove 105 corresponding to the through hole 104. The opening of the groove 105 faces downward, and grooves 105 are provided on both end faces of the inlet and outlet of the through hole 104.

[0106] In order to enable the cooling pipe 106 to pass through the through hole 104, it is necessary to provide a through hole 104 or a groove 105 in the upper pole column 101; the through hole 104 or the groove 105 in the upper pole column 101 needs to correspond to the through hole 104 of the lower pole column 102, so that after the upper pole column 101 and the lower pole column 102 are assembled to form the pole column 100, the cooling pipe 106 can pass through the through hole 104.

[0107] In the cover assembly 10 including the pole column assembly of the present application, the cover plate 110, the first plastic part 120, the second plastic part 130 and the seal 140 are all provided with pole column holes 111 for the pole column 100 to pass through, for example, the pole column hole 111 for the column body part 121 of the lower pole column 102 to pass through.

[0108] The above-mentioned first plastic part 120 can also be called the first insulating part or the upper insulating part, and the second plastic part 130 can also be called the second insulating part or the lower insulating part. The first plastic part 120 is arranged on one side of the cover plate 110 in the thickness direction, and the second plastic part 130 is arranged on the other side of the cover plate 110 in the thickness direction. For example, the first plastic part 120 is arranged on the upper side of the cover plate 110, and the second plastic part 130 is arranged on the lower side of the cover plate 110. The column body part 121 of the lower pole column 102 can pass through the second plastic part 130, the cover plate 110 and the first plastic part 120 in sequence; and the through hole 104 in the lower pole column 102 is located outside the first plastic part 120, that is, the through hole 104 in the lower pole column 102 protrudes relative to the first plastic part 120. Further, the first plastic part 120 can be arranged between the upper pole column 101 and the cover plate 110. Optionally, the outer diameter of the first plastic part 120 can be adapted to the outer diameter of the upper pole column 101.

[0109] It should be understood that the first plastic part 120 is padded between the upper pole column 101 and the cover plate 110, which can play an insulating role, prevent electrical connection between the upper pole column 101 and the cover plate 110, and avoid short circuit of the battery.

[0110] In addition, the first plastic part 120 and the second plastic part 130 can limit the pole column 100 in the height direction of the pole column 100, avoid the pole column 100 from moving up or down, and improve the assembly stability of the pole column 100.

[0111] In the cover assembly 10 including the pole column assembly of the present application, the seal 140 can be an O-ring. The seal 140 can be sleeved on the pole column 100, such as on the column body portion 121 of the lower pole column 102, and the seal 140 is located between the column body portion 121 and the pole column hole 111. Optionally, the seal 140 in the embodiment of the present application can be a seal 140 with an "L"-shaped cross-section. By applying pressure to the seal member through the plate body portion 122 of the lower pole column 102 and the cover plate 110, the seal 140 can play a sealing role between the plate body portion 122 and the cover plate 110, preventing foreign objects from entering the battery cell 20 and preventing the electrolyte inside the battery cell 20 from leaking to the outside.

[0112] In the cover assembly 10 including the pole column assembly of the present application, along the length direction of the cover plate 110, a first pole column and a second pole column are arranged at intervals, such as a positive pole column and a negative pole column, and both the positive pole column and the negative pole column can adopt the pole column 100 provided in any of the above embodiments of the present application. One cooling pipe 106 can penetrate through the through hole 104 opened in the positive pole column, and another cooling pipe 106 can penetrate through the through hole 104 opened in the negative pole column; alternatively, one cooling pipe 106 can cool the positive pole column and the negative pole column of the same battery at the same time.

[0113] In the battery module 40 including the pole column assembly of the present application, when a plurality of battery cells 30 are arranged along the first direction, the through holes 104 on each battery cell 30 are correspondingly arranged and communicated with each other, and the cooling pipe 106 sequentially passes through the through holes 104 on each battery cell 30 along the first direction. That is, the battery cells 20 of the pole column 100 provided with the through hole 104 and the battery cells 20 are arranged along the thickness direction of the battery cell 20, and the through holes 104 of the pole columns 100 of each battery cell 20 are also communicated with each other. The cooling pipe 106 passes through the through holes 104 of the pole columns 100 of each battery cell 20 to connect each battery cell 20.

[0114] In the battery module 40 of the present application, one cooling pipe 106 can be arranged in contact with a plurality of pole columns 100. As an example, one cooling pipe 106 can cool the pole columns 100 on the same side of a plurality of batteries in the same battery module 40 at the same time. For example, one cooling pipe 106 is used to cool the positive pole columns on the same side of a plurality of batteries in the same battery module 40 at the same time, and another cooling pipe 106 is used to cool the negative pole columns on the same side of a plurality of batteries in the same battery module 40 at the same time. A plurality of pole columns 100 share the same cooling pipe 106, and other cooling structures (such as a cooling water source, a water pump, etc.) matching the cooling pipe 106 can also share a set, simplifying the system structure. Alternatively, in other embodiments, one cooling pipe 106 can also be used to cool the positive pole column and the negative pole column of the same battery module 40 at the same time.

[0115] The present application will be further described below in conjunction with specific embodiments and comparative examples.

[0116] Example 1

[0117] The battery cell 30 includes: a housing, a battery core 20 disposed within the housing, and a cover assembly 10 sealingly connected to the housing; wherein, the cover assembly 10 includes a cover plate 110, a first plastic part 120, a second plastic part 130, a sealing member 140, and a terminal assembly. The terminal assembly includes a terminal 100 and a cooling tube 106. The terminal 100 includes a terminal body 103 and a through hole 104 extending through the terminal body 103 along a first direction. The cooling tube 106 is disposed within the through hole 104, and a cooling medium is accommodated within the cooling tube 106.

[0118] A water cooling structure is further provided on any side of the battery cell 30.

[0119] In this embodiment, the distance a between the top wall of the through hole 104 and the upper surface of the terminal body 103 is 2 mm; the distance b between the bottom wall of the through hole 104 and the lower surface of the terminal body 103 is 1.5 mm.

[0120] Example 2

[0121] This embodiment is substantially the same as Example 1, except that:

[0122] The distance a between the top wall of the through hole 104 and the upper surface of the terminal body 103 is 2.5 mm;

[0123] The distance b between the bottom wall of the through hole 104 and the lower surface of the terminal body 103 is 2 mm.

[0124] Example 3

[0125] This embodiment is substantially the same as Example 1, except that:

[0126] The distance a between the top wall of the through hole 104 and the upper surface of the terminal body 103 is 3 mm;

[0127] The distance b between the bottom wall of the through hole 104 and the lower surface of the terminal body 103 is 3.5 mm.

[0128] Example 4

[0129] This embodiment is substantially the same as Example 1, except that:

[0130] The distance a between the top wall of the through hole 104 and the upper surface of the terminal body 103 is 4 mm;

[0131] The distance b between the bottom wall of the through hole 104 and the lower surface of the terminal body 103 is 4 mm.

[0132] Example 5

[0133] This embodiment is basically the same as Embodiment 1, except that:

[0134] The distance a between the top wall of the through hole 104 and the upper surface of the pole column body 103 is 5 mm;

[0135] The distance b between the bottom wall of the through hole 104 and the lower surface of the pole column body 103 is 5 mm.

[0136] Comparative Example 1

[0137] This comparative example is basically the same as Embodiment 1, except that:

[0138] The distance a between the top wall of the through hole 104 and the upper surface of the pole column body 103 is 1.5 mm;

[0139] The distance b between the bottom wall of the through hole 104 and the lower surface of the pole column body 103 is 1 mm.

[0140] Comparative Example 2

[0141] This comparative example is basically the same as Embodiment 1, except that:

[0142] The distance a between the top wall of the through hole 104 and the upper surface of the pole column body 103 is 6 mm;

[0143] The distance b between the bottom wall of the through hole 104 and the lower surface of the pole column body 103 is 6 mm.

[0144] Comparative Example 3 (fully adiabatic)

[0145] In the battery cell of this comparative example, no water cooling structure is provided on any side of the battery cell, and no holes are opened in the pole column, that is, the above-mentioned pole column cooling structure is not provided.

[0146] Comparative Example 4 (only side water cooling)

[0147] In the battery cell of this comparative example, no holes are opened in the pole column, that is, the above-mentioned pole column cooling structure is not provided.

[0148] Performance result characterization

[0149] 1. Characterize the battery cells of the above-mentioned Embodiments 1-5 and Comparative Examples 1-2, and characterize whether the specific numerical settings of the above a and b are appropriate through actual welding tests; for example, in the preparation process of the battery cell, use welding to connect the cover assembly and other structures. During the welding operation, if the depth of the molten pool does not reach the through hole, the insert block has no deformation, and there is no explosion hole in the welding, it means that the set value of a or b is OK.

[0150] The results are shown in Tables 1 and 2 below.

[0151] Table 1

[0152]

[0153]

[0154] Table 2

[0155]

[0156] 2. Perform a temperature rise test on the battery cells of the above-mentioned Example 1 and Comparative Examples 3-4, including: arranging temperature sensing wires outside the battery, continuously charging the battery at a constant rate until it is fully charged, and monitoring and recording the temperature conditions at different positions (such as the positive electrode terminal, negative electrode terminal, positive electrode tab, negative electrode tab, large surface, etc.).

[0157] The test results are as Figures 9 to 11 and shown in Table 3 below.

[0158] Table 3

[0159]

[0160] It should be noted that in Table 3, the temperature thresholds of the positive electrode structural member and the negative electrode structural member are 65 °C, and the temperature threshold of the electrode group is 68 °C. The temperature threshold of the structural member is set to 65 °C because the service life of the structural member, especially components such as the seal and the upper plastic part, will be significantly reduced after exceeding 65 °C. The temperature threshold of the electrode group is set to 68 °C mainly because the electrolyte inside the battery cell will decompose and the cycle performance / service life of the battery cell will decline when the temperature exceeds this value.

[0161] From Figures 9 to 11 and Table 3, it can be seen that in Comparative Example 1, complete adiabaticity, that is, no cooling treatment method is adopted, resulting in too high battery temperature. In Comparative Example 2, the side water cooling method is adopted. Only relying on side water cooling, although the battery temperature can be reduced by nearly 20 °C, the temperature of the structural member is basically the same as that of the electrode group, and it is still at a relatively high temperature, not meeting the bad temperature threshold requirements. In Example 1 of the present application, on the basis of side water cooling, a pole cooling scheme is added, further reducing the temperature, especially the temperature of the structural member, by a further 7-9 °C, so as to meet the temperature rise requirements of the battery.

[0162] The parts not detailed in the present invention are well-known technologies to those skilled in the art.

[0163] The basic principles of the present invention have been described above in connection with specific embodiments. However, it should be noted that the advantages, benefits, effects, etc. mentioned in the present invention are only examples and not limitations. It cannot be considered that these advantages, benefits, effects, etc. are essential for each embodiment of the present invention. In addition, the above-disclosed specific details are only for the purpose of illustration and facilitating understanding, rather than limitations. The above details do not limit the present invention to necessarily adopt the above specific details for implementation.

[0164] It should be noted that the term "and / or" or " / " used herein is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The singular forms "a", "the", and "said" used in the embodiments of the present invention and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0165] In the description of the embodiments of the present application, the orientation or positional relationship indicated by technical terms such as "length", "width", "inner", "outer", "top", "bottom", "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed, operated, or used in a specific orientation. Therefore, it should not be construed as a limitation to the embodiments of the present application.

[0166] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "install", "connect", "couple", "fix", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can also be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0167] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A terminal component, characterized in that, The pole assembly includes: A pole (100), the pole (100) includes a pole body (103) and a through hole (104) penetrating the pole body (103), the through hole (104) penetrates the pole body (103) along a first direction, the distance between the top wall of the through hole (104) and the upper surface of the pole body (103) is greater than 0, and the distance between the bottom wall of the through hole (104) and the lower surface of the pole body (103) is greater than 0; A cooling pipe (106), the cooling pipe (106) is disposed in the through hole (104), and a cooling medium is accommodated in the cooling pipe (106); The first direction is parallel to the width direction of the cover plate including the pole assembly.

2. The pole column assembly according to claim 1, wherein, The distance between the top wall of the through hole (104) and the upper surface of the pole body (103) is a, and the a satisfies: 2mm ≤ a ≤ 5mm; And / or, the distance between the bottom wall of the through hole (104) and the lower surface of the pole body (103) is b, and the b satisfies: 1.5mm ≤ b ≤ 5mm.

3. The pole column assembly according to claim 1, wherein A gap space is provided between the inner wall of the through hole (104) and the outer wall of the cooling pipe (106), and a filling medium (107) is provided in the gap space, and the thermal conductivity of the filling medium (107) ≥ 400W / (m·K).

4. The terminal assembly according to claim 3, characterized in that, The filling medium (107) includes at least one of carbon nanotube glue or silver glue.

5. The pole assembly according to any one of claims 1 to 4, characterized in that The pole (100) includes an upper pole (101) and a lower pole (102), the pole body (103) of the lower pole (102) includes a columnar part (121) and a plate part (122), and the through hole (104) is provided in the columnar part (121); The plate part (122) is disposed around the bottom edge of the columnar part (121) and is connected to the columnar part (121), and the size of the outer contour of the plate part (122) is greater than the size of the outer contour of the columnar part (121); The upper pole (101) is connected to the outside of the columnar part (121).

6. The pole assembly according to claim 5, wherein, The upper pole (101) is provided with a groove (105) corresponding to the through hole (104), the opening of the groove (105) faces downward, and the groove (105) is provided on both end faces of the inlet and outlet of the through hole (104).

7. A cover assembly, characterized in that, The cover plate assembly (10) includes: A cover plate (110), the cover plate (110) is provided with a pole hole (111); The pole assembly according to any one of claims 1 to 6, at least a part of the pole (100) in the pole assembly penetrates into the pole hole (111), and the through hole (104) in the pole (100) and the cooling pipe (106) disposed in the through hole (104) are both above the upper surface of the cover plate (110).

8. The cover assembly according to claim 7, characterized in that, The cover plate assembly (10) further includes a first plastic part (120), a second plastic part (130) and a seal (140); The first plastic part (120), the second plastic part (130) and the seal (140) are all provided with a pole hole (111) for the pole column (100) to pass through; The first plastic part (120) is arranged on one side of the cover plate (110) in the thickness direction, and the second plastic part (130) is arranged on the other side of the cover plate (110) in the thickness direction; the seal (140) is arranged between the pole column body (103) and the pole hole (111), and is adapted to seal and connect the pole column (100) and the cover plate (110).

9. A battery cell, characterized in that, The battery cell (30) includes: a battery core (20); The cover plate assembly (10) according to any one of claims 7 to 8, which is arranged at one end or both ends of the battery cell (30), and the pole column (100) is electrically connected to the battery core (20).

10. A battery module, characterized in that, The battery module (40) includes a plurality of battery cells (30) as claimed in claim 9; The plurality of battery cells (30) are arranged in a row along the first direction; The through holes (104) on each of the battery cells (30) are arranged correspondingly, and the cooling pipe (106) sequentially passes through the through holes (104) on each of the battery cells (30) along the first direction.

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