A battery pack and thermal management system

Abstract

The application provides a battery pack and a thermal management system. The battery pack comprises a box, a battery cell module, a first pipeline, a liquid inlet pipe and a liquid return pipe. The box has an accommodating cavity formed therein. The battery cell module comprises a plurality of stacked battery cells, and is installed in the accommodating cavity. The first pipeline is attached to the battery cell module. One end of the liquid inlet pipe extends to between adjacent battery cells or beside the battery cells. One end of the liquid return pipe extends to between adjacent battery cells or beside the battery cells. The other end of one of the first pipeline, the liquid inlet pipe and the liquid return pipe is in communication. The battery cells and the first pipeline are immersed in the cooling liquid and arranged close to the battery cells, so that the cooling effect on the battery cells is improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a battery pack and thermal management system. Background Technology

[0002] With the rapid development of battery technology, the cells inside the battery pack generate heat when the battery pack is working. Some existing technologies cool the cells by immersing them in coolant. However, immersion cooling regulates the overall temperature of all components in the battery pack and cannot precisely cool the cells, resulting in poor cooling effect. Summary of the Invention

[0003] In view of this, this application provides a battery pack that solves the problem that when the battery cells are submerged in coolant for cooling, precise cooling of the cell location is impossible, resulting in poor cooling performance. This application also provides a thermal management system including the above-mentioned battery pack.

[0004] To achieve the above objectives, this application provides the following technical solution:

[0005] A battery pack, comprising:

[0006] The box-shaped enclosure has an internal cavity for receiving contents.

[0007] A battery cell module includes multiple stacked battery cells, and the battery cell module is installed in the receiving cavity;

[0008] The first conduit is attached to the battery cell module;

[0009] The liquid inlet pipe extends at one end to the space between adjacent battery cells or to the side of the battery cell;

[0010] The return pipe extends at one end to the space between adjacent cells or to the side of the cell;

[0011] The first conduit is connected to the other end of one of the inlet pipe and the return pipe. Optionally, a second conduit is also included, which is attached to the battery cell module and is connected to the other end of the other of the inlet pipe and the return pipe.

[0012] Optionally, in the first direction, the first conduit is disposed on one side of the receiving cavity and covers part of the battery cell module, the second conduit includes a first unit and a second unit disposed on the other side of the receiving cavity and covers the remaining part of the battery cell module, and the first unit is arranged around the first conduit.

[0013] Optionally, the first pipeline and / or the second pipeline are arranged in a mesh pattern.

[0014] Optionally, the first pipeline and / or the second pipeline are disposed on the top of the explosion-proof valve of the battery cell, and at least part of the first pipeline and / or the second pipeline disposed in relation to the explosion-proof valve is a heat-fusion pipe.

[0015] Optionally, in the second direction,

[0016] The inlet pipe is located in the middle of the cell module, and at least two return pipes are provided, located at the two ends of the cell module respectively; or,

[0017] At least two inlet pipes are provided, located at opposite ends of the battery cell module, and the return pipe is located in the middle of the battery cell module; or,

[0018] The liquid inlet pipe is located at one end of the battery cell module, and the liquid return pipe is located at the other end of the battery cell module.

[0019] Optionally, it also includes a crossbeam located in the middle of the housing and dividing the receiving cavity into two mounting cavities, with each mounting cavity containing the battery cell module. The liquid inlet pipe is located near the crossbeam, and the liquid return pipe is located at the end of the housing away from the crossbeam.

[0020] Optionally, in the third direction, the receiving cavity is divided into a first zone, a second zone, and a third zone in sequence;

[0021] The area of ​​the battery cell module covered by the first conduit and / or the second conduit in the first area is M, the area of ​​the battery cell module covered by the first conduit and / or the second conduit in the second area is N, and the area of ​​the battery cell module covered by the first conduit and / or the second conduit in the third area is P, wherein M, N and P satisfy: M > P, M > N.

[0022] Optionally, the cross-section of the first pipeline and / or the second pipeline is flat, the width of the pipeline is b, the height of the pipeline is h, and 10mm≤b≤150mm, 2.5mm≤h<10mm.

[0023] Optionally, the first pipeline and / or the second pipeline are provided with a resistance-reducing section, and the flow cross-sectional area of ​​the resistance-reducing section is larger than the flow cross-sectional area of ​​the remaining parts of the first pipeline and / or the second pipeline.

[0024] Optionally, in the direction of the cell height, the outlet of the inlet pipe and the inlet of the return pipe are both lower than the top edge of the cell, wherein the length of the inlet pipe extending into the receiving cavity is less than half the height of the cell, and the length of the return pipe extending into the receiving cavity is greater than or equal to half the height of the cell and less than the height of the cell.

[0025] Optionally, a cover may be included, which is integrated with the first conduit and / or the second conduit.

[0026] Optionally, multiple inlet pipes and return pipes are provided, and they are all uniformly arranged along the direction of the battery cell stacking, and the gaps between adjacent battery cells form a through flow channel.

[0027] Optionally, the first pipeline includes a connection portion that connects to the plurality of liquid inlet pipes, wherein the flow cross-sectional area of ​​the connection portion is larger than the flow cross-sectional area of ​​the rest of the first pipeline.

[0028] Optionally, it includes a main liquid inlet connected to the first pipeline and a main liquid return port connected to the second pipeline, wherein the main liquid inlet and the main liquid return port are located on the power-connected side of the housing.

[0029] A thermal management system includes a circulation pump, a radiator, an expansion tank, a throttle valve, and a battery pack as described in any one of the above, wherein,

[0030] The circulation pump is connected to the first pipeline of the battery pack;

[0031] One end of the radiator is connected to the second pipeline of the battery pack, and the other end is connected to the circulation pump;

[0032] One end of the expansion tank is connected to the battery pack, and the other end is connected to the circulation pump; and / or, one end of the expansion tank is connected to the radiator, and the other end is connected to the circulation pump;

[0033] The throttle valve is disposed between the expansion tank and the radiator, and / or between the expansion tank and the battery pack.

[0034] The battery pack provided in this application, by attaching a first conduit to the cell module and connecting the first conduit to either the inlet pipe or the return pipe, allows the first conduit to initially cool the cells in the cell module when the coolant flows through it. Furthermore, the inlet pipe injects coolant into the cavity containing the cells, where the coolant cools the cells through contact. The coolant is then discharged through the return pipe. This solution improves the cooling effect of the cells by combining coolant immersion in the cells with the proximity of the first conduit to the cells. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0036] Figure 1 This is an exploded view of the battery pack provided in this embodiment;

[0037] Figure 2 This is the front view of the exploded view;

[0038] Figure 3 A 3D model of the hidden box and lid;

[0039] Figure 4 A top view showing the concealed box and lid;

[0040] Figure 5 This is a front view showing the concealed box and lid.

[0041] Figure 6 A bottom view showing the concealed bottom plate of the enclosure;

[0042] Figure 7 This is a schematic diagram of a thermal management system.

[0043] exist Figures 1-7 middle:

[0044] 1-Box body, 2-Battery cell module, 3-First pipeline, 4-Inlet pipe, 5-Return pipe, 6-Second pipeline, 7-Crossbeam, 8-Cover body, 9-Main inlet, 10-Main return port, 11-Circulation pump, 12-Radiator, 13-Expansion tank, 14-Throttle valve, 15-Battery pack;

[0045] 201 - Battery cell, 301 - Connector, 601 - Resistance reduction section;

[0046] 2011 - Explosion-proof valve. Detailed Implementation

[0047] This application provides a battery pack. This application also provides a thermal management system including the above-described battery pack.

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] like Figures 1 to 7 As shown, this application embodiment provides a battery pack 15, which is an integral unit assembled from multiple battery modules for storing and providing electrical energy. It mainly includes a housing 1, cell modules 2, a first pipeline 3, an inlet pipe 4, and a return pipe 5. The housing 1 has an internal cavity. The cell module 2 includes multiple stacked cells 201, which are installed within the cavity and located inside the housing 1. The cell 201 is the most basic component of the battery, typically an electrochemical device encapsulated in a metal casing. The housing 1 provides installation space for the cell module 2. The first pipeline 3 is fitted to the cell module 2 and serves as a flow channel for the heat exchange medium. The first pipe 3 is attached to the battery cell module 2. When the heat exchange medium in the first pipe 3 flows, it will cool the battery cell 201 through heat conduction. One end of the liquid inlet pipe 4 extends between adjacent battery cells 201 or to the side of battery cells 201, and one end of the liquid return pipe 5 extends between adjacent battery cells 201 or to the side of battery cells 201. The liquid inlet pipe 4 is used to inject the heat exchange medium into the box 1 where the battery cell module 2 is installed, and the liquid return pipe 5 is used to discharge the heat exchange medium in the box 1, thereby realizing the circulation of the heat exchange medium in the box 1 to cool the battery cell 201.

[0050] In this configuration, the first pipe 3 is connected to the other end of either the inlet pipe 4 or the return pipe 5. For example, when the first pipe 3 is connected to the inlet pipe 4, the heat exchange medium first enters the first pipe 3. During the flow of the heat exchange medium in the first pipe 3, since the first pipe 3 is in contact with the battery cell 201, the heat exchange medium flowing in the first pipe 3 initially cools the battery cell 201. Then, the heat exchange medium flows from the inlet pipe 4 to the housing 1 where the battery cell 201 is located. The heat exchange medium contacts the battery cell 201 in the housing 1 again, cooling the battery cell 201. Then, the return pipe 5 discharges the heat exchange medium, thus completing one flow cycle of the heat exchange medium in this manner. When the first pipe 3 is connected to the return pipe 5, the heat exchange medium... First, the heat exchange medium enters the housing 1 containing the battery cell 201 through the inlet pipe 4. The heat exchange medium comes into contact with the battery cell 201 and performs an initial cooling of the battery cell 201 in the housing 1. Then, the heat exchange medium enters the first pipeline 3 through the return pipe 5. Although this part of the heat exchange medium has performed an initial cooling of the battery cell 201, the temperature of the heat exchange medium does not rise much, or the temperature of the heat exchange medium may be lower than the temperature of the battery cell 201. Then, the heat exchange medium in the housing 1 will flow to the first pipeline 3 through the return pipe 5. Since the first pipeline 3 is in contact with the battery cell 201, the heat exchange medium flowing in the first pipeline 3 will cool the battery cell 201 again. This completes one flow cycle of the heat exchange medium in this way.

[0051] Here, the heat exchange medium flowing in the first pipe 3 is not limited to any particular type. It can be a coolant, a cooling gas (a gas with a temperature lower than that of the battery cell 201), or a mixture of both, as long as it can cool the battery cell 201. Correspondingly, the heat exchange medium flowing in the inlet pipe 4 and the return pipe 5 is the same as that flowing in the first pipe 3; it can be a coolant, a cooling gas, or a mixture of both.

[0052] It should be noted that the bonding between the first conduit 3 and the cell module 2 not only includes the two being tightly bonded without any other structure in between, allowing the first conduit 3 to cool the cell 201 in the cell module 2 through heat conduction, but also includes the first conduit 3 being bonded to the cell module 2 through thermally conductive adhesive, or other thermally conductive components being placed between the first conduit 3 and the cell module 2. Here, the bonding between the first conduit 3 and the cell module 2 means that heat conduction can occur between the cell module 2 and the first conduit 3, and the first conduit 3 can cool the cell module 2.

[0053] It should also be noted that one end of the liquid inlet pipe 4 extends between adjacent battery cells 201 or beside battery cells 201, so that the heat exchange medium cools the battery cells 201 immediately, thereby improving the cooling effect of the heat exchange medium on the battery cells 201; one end of the liquid return pipe 5 extends between adjacent battery cells 201 or beside battery cells 201. Preferably, the liquid inlet pipe 4 and the liquid return pipe 5 are arranged in the housing 1 between different battery cells 201 or beside different battery cells 201, and the liquid return pipe 5 is used to discharge the heat exchange medium after cooling the battery cells 201 out of the housing 1.

[0054] It should also be noted that one end of the inlet pipe 4 refers to the outlet end of the heat exchange medium, and the other end of the inlet pipe 4 refers to the inlet end of the heat exchange medium. One end of the return pipe 5 refers to the inlet pipe 4 of the heat exchange medium, and the other end of the return pipe 5 refers to the outlet end of the heat exchange medium.

[0055] The battery pack 15 with the above structure, by attaching the first pipe 3 to the cell module 2 and connecting the first pipe 3 to one of the inlet pipe 4 and the return pipe 5, allows the heat exchange medium to initially cool the cell 201 in the cell module 2 when it flows in the first pipe 3. Furthermore, the inlet pipe 4 injects the heat exchange medium into the housing 1 containing the cell 201, where the heat exchange medium cools the cell 201 through contact. The heat exchange medium is then discharged through the return pipe 5. This solution improves the cooling effect of the cell 201 by combining the immersion of the cell 201 in the heat exchange medium with the proximity of the first pipe 3 to the cell 201.

[0056] It should be noted that in the following embodiments, the heat exchange medium is a coolant as an example.

[0057] Furthermore, in some embodiments, the battery pack 15 further includes a second conduit 6, which is attached to the cell module 2 and connected to the other end of either the inlet pipe 4 or the return pipe 5. Specifically, based on the first conduit 3 being connected to the other end of either the inlet pipe 4 or the return pipe 5, the second conduit 6 is connected to the other end of either the inlet pipe 4 or the return pipe 5. Wherein, the first conduit 3 can be the inlet pipe 4, in which case the second conduit 6 is the return pipe 5; or the first conduit 3 can be the return pipe 5, in which case the second conduit 6 is the inlet pipe 4. Thus, the first conduit 3 and the second conduit 6 can be configured in three ways: the battery pack 15 can only have either the inlet pipe 4 or the return pipe 5, as described in the above embodiments; the battery pack 15 can also have both the inlet pipe 4 and the return pipe 5.

[0058] For example, the first pipe 3 is the inlet pipe 4, and the second pipe 6 is the return pipe 5. In this way, both the first pipe 3 and the second pipe 6 are in contact with the battery cell module 2. At this time, when the first pipe 3 is connected to the inlet pipe 4 and the second pipe 6 is connected to the return pipe 5, the coolant first enters the first pipe 3. During the flow of the coolant in the first pipe 3, since the first pipe 3 is in contact with the battery cell 201, the coolant flowing in the first pipe 3 will initially cool the battery cell 201. Then the coolant flows from the inlet pipe 4 to the housing 1 where the battery cell 201 is located. The coolant will cool the battery cell 201 in the housing 1 again. After that, the coolant is guided to the second pipe 6 by the return pipe 5. The coolant flowing in the second pipe 6 will cool the battery cell 201 again, thus completing one coolant flow cycle.

[0059] With this configuration, the coolant flows sequentially through the first pipe 3, the inlet pipe 4, the battery cell 201, the return pipe 5, and the second pipe 6, increasing the flow path of the coolant, increasing the number of times the coolant contacts the battery cell 201, increasing the number of times the battery cell 201 is cooled, and further improving the cooling effect on the battery cell 201.

[0060] It should also be noted that the inlet pipe 4 and the return pipe 5 can be tubular structures, or they can be inlet holes or return holes opened on the first pipe 3 and the second pipe 6.

[0061] It should also be noted that the arrangement of the first conduit 3 and the second conduit 6 is not unique. An exemplary arrangement could be as follows: both the first conduit 3 and the second conduit 6 could be located at the top of the cell module 2 (see [link to relevant documentation]). Figures 1-6 The first pipe 3 is located at the top of the cell module 2, and the second pipe 6 is located at the bottom of the cell module 2; the first pipe 3 is located at the bottom of the cell module 2, and the second pipe 6 is located at the top of the cell module 2; both the first pipe 3 and the second pipe 6 are located at the bottom of the cell module 2.

[0062] In some embodiments, in a first direction, a first conduit 3 is disposed on one side of the receiving cavity and covers a portion of the battery cell module 2, and a second conduit 6 includes a first unit and a second unit disposed on the other side of the receiving cavity and covers the remaining portion of the battery cell module 2, and the first unit is arranged around the first conduit 3. Specifically, taking the first pipe 3 as the coolant inlet pipe 4 and the second pipe 6 as the coolant return pipe 5 as an example, the first pipe 3 definitely covers a larger area of ​​the cell module 2, and its cooling effect on the cell module 2 is better. However, considering the volume of the internal cavity of the battery pack 15 and the setting position of the second pipe 6, if the first pipe 3 covers all the cell modules 2 in the cavity, the second pipe 6 cannot be reasonably arranged, or in other words, multiple second pipes 6 need to be set, which is inconvenient for the overall planning and setting of the battery pack 15. In addition, in the process of cooling the cell 201 through heat conduction and the coolant contact cooling of the cell 201 by the first pipe 3 and / or the second pipe 6, contact cooling plays a dominant role. Therefore, the first pipe 3 is set on one side of the cavity and covers part of the cell module 2. The second pipe 6 includes a first unit and a second unit set on the other side of the cavity and covers the remaining part of the cell module 2. The first unit is arranged around the first pipe 3. This configuration improves the rationality of the layout of the first pipeline 3 and the second pipeline 6 in the battery pack 15, and facilitates the arrangement of the total liquid inlet 9 connected to the first pipeline 3 and the total liquid return outlet 10 connected to the second pipeline 6, making the overall layout of the battery pack 15 more compact and improving the energy density of the battery pack 15.

[0063] It should be noted that the first direction can be along the time axis. Figure 1 The direction indicated by the double-headed arrow A can also be along... Figure 1 The direction indicated by the double-headed arrow B can also be a direction between directions A and B.

[0064] In some embodiments, the first pipe 3 and / or the second pipe 6 are arranged in a mesh pattern. Specifically, in a typical battery pack 15, multiple cell modules 2 are arranged side by side or in an array, and each cell module 2 is formed by stacking multiple cells 201. Here, the first pipe 3 and / or the second pipe 6 are arranged in a mesh structure. Preferably, the layout of the pipes in the first pipe 3 and the second pipe 6 is the same as the arrangement direction of the cells 201. In this way, when the coolant flows in the first pipe 3 and the second pipe 6, the contact area between the first pipe 3 and the second pipe 6 and the cells 201 can be increased, thereby improving the cooling effect on the cells 201.

[0065] Specifically, the first pipeline 3 and / or the second pipeline 6 are arranged in a mesh pattern, which means that the pipelines are arranged in a rectangular, star-shaped, triangular, polygonal, or fan-shaped array, or the first pipeline 3 and / or the second pipeline 6 each include multiple interconnected sub-pipelines, and the multiple sub-pipelines are arranged in a mesh pattern.

[0066] In some embodiments, the first conduit 3 and / or the second conduit 6 are disposed on the top of the explosion-proof valve 2011 of the battery cell 201, and at least part of the first conduit 3 and / or the second conduit 6 disposed on the explosion-proof valve 2011 are heat-fused conduits. Specifically, multiple battery cells 201 are stacked to form a battery cell module 2. Part of the first pipe 3 and / or the second pipe 6 is located on top of the explosion-proof valve 2011 of the battery cell 201. The first pipe 3 and / or the second pipe 6, which are aligned with the explosion-proof valve 2011, are heat-fusible pipes. Heat-fusible pipes are pipes that melt when heated. In the event of a thermal runaway fault in the battery, the high-temperature and high-pressure gas-liquid mixture inside the battery will rush out of the explosion-proof valve 2011. Since the heat-fusible pipe is aligned with the explosion-proof valve 2011, the high-temperature and high-pressure gas will melt the heat-fusible pipe, and the coolant in the first pipe 3 and / or the second pipe 6 will flow out, thereby rapidly cooling the battery cell 201 that has experienced thermal runaway. This achieves rapid cooling of the faulty battery cell 201, improves the safety of the battery pack 15, and also prevents the battery cell 201 that has experienced thermal runaway from affecting the normal operation of other battery cells 201, thus ensuring the normal use of the battery pack 15.

[0067] It should be noted that at least part of the first pipeline 3 and / or the second pipeline 6 of the aligned explosion-proof valve 2011 are heat-fusion pipes. The aligned configuration includes not only the heat-fusion pipe and the explosion-proof valve 2011... Figure 1 The alignment direction indicated by the double-headed arrow A also includes situations where the two align in the same direction. In other words, when the cell 201 experiences thermal runaway and high-temperature, high-pressure gas is ejected from the explosion-proof valve 2011, it is sufficient to ensure that the hot melt tube can melt immediately to precisely cool down the cell 201 that has experienced thermal runaway.

[0068] In addition, the first pipe 3 and / or the second pipe 6 may also be located at the bottom of the explosion-proof valve 2011 of the battery cell 201.

[0069] In some embodiments, in the second direction, the liquid inlet pipe 4 is located in the middle of the cell module 2, and at least two liquid return pipes 5 are provided, respectively located at both ends of the cell module 2; or, at least two liquid inlet pipes 4 are provided, respectively located at both ends of the cell module 2, and the liquid return pipe 5 is located in the middle of the cell module 2; or, the liquid inlet pipe 4 is located at one end of the cell module 2, and the liquid return pipe 5 is located at the other end of the cell module 2.

[0070] Specifically, when the inlet pipe 4 is located in the middle of the cell module 2 and the return pipe 5 is located at both ends of the cell module 2, the coolant enters the middle of the cell module 2 from the inlet pipe 4 and flows from the middle to both ends, thus cooling all the cells 201 in the cell modules 2 of the housing 1. When the inlet pipe 4 is located at both ends of the cell module 2 and the return pipe 5 is located in the middle of the cell module 2, the coolant enters the ends of the cell module 2 from the inlet pipe 4, cooling... The coolant flows from both ends of the cell module 2 to the center, thus cooling all the cells 201 in the cell modules 2 of the housing 1. When the inlet pipe 4 is located at one end of the cell module 2 and the return pipe 5 is located at the other end of the cell module 2, the coolant enters from the inlet pipe 4 at one end of the cell module 2 and flows from one end to the other end, again cooling all the cells 201 in the cell modules 2 of the housing 1. This cooling system effectively cools all the cells 201 inside the housing 1, improving the cooling effect of the coolant on the cells 201.

[0071] It should be noted that the middle part of the cell module 2 refers to the middle part of all cell modules 2 inside the housing 1, and correspondingly, the two ends of the cell module 2 refer to the two ends of all cell modules 2 inside the housing 1.

[0072] It should also be noted that the second direction can be the same as or different from the first direction. The second direction can be... Figure 1 The direction indicated by the double-headed arrow A can also be the direction indicated by the double-headed arrow B, or the direction located between the double-headed arrow A and the double-headed arrow B.

[0073] In some embodiments, the battery pack 15 further includes a crossbeam 7 located in the middle of the housing 1 and dividing the receiving cavity into two mounting cavities, each of which a cell module 2 is mounted. An inlet pipe 4 is positioned near the crossbeam 7, and a return pipe 5 is located at the end of the housing 1 away from the crossbeam 7. Specifically, in Figure 1 In the direction indicated by the double-headed arrow A, i.e., along the length of the housing 1, due to the large span of the receiving cavity, a crossbeam 7 is installed in the middle region of the receiving cavity to improve the overall structural stability of the housing 1. The middle region of the receiving cavity is located at the same position as the middle of all the battery cell modules 2. The liquid inlet pipe 4 is positioned close to the crossbeam 7, which divides the receiving cavity into two chambers. Therefore, two sets of liquid inlet pipes 4 are installed, allowing the liquid inlet pipes 4 to cool the battery cell modules 2 in each of the two chambers respectively. Figure 1In the direction indicated by the bidirectional arrow A, the liquid inlet pipe 4 is located in the middle of all the battery cell modules 2. Since the heat dissipation effect of the battery cell 201 in the middle is the worst, the temperature in the middle of the box 1 is the highest. The liquid inlet pipe 4 is located close to the crossbeam 7, so that the coolant can cool down the battery cell 201 in the middle of the box 1 as soon as possible, thereby further improving the cooling effect of the battery cell 201. Moreover, setting the liquid inlet pipe 4 close to the crossbeam 7 also facilitates the fixing of the liquid inlet pipe 4. Fixing the liquid inlet pipe 4 to the crossbeam 7 improves the stability of the liquid inlet pipe 4 structure.

[0074] It should be noted that since most of the space inside the housing 1 is occupied by the cell module 2, the middle part of the housing 1 and the middle part of the cell module 2 can be considered to be the same location.

[0075] Furthermore, in the third direction, the cavity is divided into a first zone, a second zone, and a third zone in sequence; the area covered by the first conduit 3 and / or the second conduit 6 in the first zone is M, the area covered by the first conduit 3 and / or the second conduit 6 in the second zone is N, and the area covered by the first conduit 3 and / or the second conduit 6 in the third zone is P, wherein M, N, and P satisfy: M > P, M > N. In the above-described implementation, the coverage area of ​​the first pipe 3 and / or the second pipe 6 on the battery cell module 2 in the middle of the receiving cavity is maximized. Based on the liquid inlet pipe 4 being set in the middle of the housing 1, in order to further improve the cooling effect on the battery cell 201 inside the housing 1, the coverage area of ​​the first pipe 3 and / or the second pipe 6 on the battery cell 201 in the middle of the housing 1 is greater than the coverage area on the battery cell 201 at the end of the housing 1. In other words, more of the first pipe 3 and / or the second pipe 6 are arranged in the middle of the housing 1. In this way, through heat conduction between the first pipe 3 and / or the second pipe 6 and the battery cell 201, the cooling effect on the battery cell 201 is further improved.

[0076] It should be noted that the third direction can be either the same as the first direction and / or the second direction, or it can be a different direction. Specifically, the third direction can be along... Figure 1 The direction indicated by the double-headed arrow A can also be along... Figure 1 The direction indicated by the double-headed arrow B can also be a direction between directions A and B.

[0077] It should also be noted that the coverage area of ​​the first conduit 3 and / or the second conduit 6 on the battery cell 201 in the middle of the housing 1 is greater than the coverage area of ​​the battery cell 201 at the end of the housing 1. This includes both the arrangement of the first conduit 3 and / or the second conduit 6 in the middle of the housing 1 being more dense when the cross-sectional areas of the first conduit 3 and / or the second conduit 6 are equal, and the cross-sectional area of ​​the conduit in the middle of the housing 1 being greater than the cross-sectional area at other positions of the housing 1 when the cross-sectional areas of the first conduit 3 and / or the second conduit 6 are not equal.

[0078] In some embodiments, the cross-section of the first conduit 3 and / or the second conduit 6 is flat, the width of the conduit is b, the height of the conduit is h, and 11mm ≤ b ≤ 150mm, 2.5mm ≤ h < 11mm. Specifically, setting the cross-section of the first conduit 3 and / or the second conduit 6 to be flat can increase the contact area between the first conduit 3 and / or the second conduit 6 and the battery cell 201, thereby ensuring the cooling efficiency of the battery cell 201. Moreover, since the cross-section of the first conduit 3 and / or the second conduit 6 is flat, it can reduce the amount of heat in the battery pack 15. Figure 1 The dimensions in the direction of the double-headed arrow C reduce the size of the non-discharge cells, thereby increasing the energy density of the battery.

[0079] It should be noted that when the first pipe 3 and / or the second pipe 6 are along Figure 1 When arranged in the direction indicated by the double-headed arrow A, the width of the pipe refers to the width of the pipe within... Figure 1 The dimension in the direction of the double-headed arrow B; when the first pipe 3 and / or the second pipe 6 are along Figure 1 When arranged in the direction indicated by the double-headed arrow B, the width of the pipe refers to the width of the pipe within... Figure 1 The dimension in the direction of the double-headed arrow A; while the height of the pipe refers to the pipe's position in the direction of the double-headed arrow A. Figure 1 The dimension in the direction of the double-headed arrow C.

[0080] Preferably, 11mm≤b≤30mm and 2.5mm≤h≤4mm are used to set the width and height of the pipes in the first pipe 3 and / or the second pipe 6 within this range, which can further make the flow channels more densely arranged while ensuring the flow speed of the flow channels.

[0081] Specifically, the width of the pipes in the first pipe 3 and / or the second pipe 6 can be 11mm, 15mm, 20mm, 25mm, 30mm, 50mm, 90mm, 110mm, 130mm, or 150mm, and the height of the pipes in the first pipe 3 and / or the second pipe 6 can be 2.5mm, 2.9mm, 3mm, 3.2mm, 3.5mm, 3.9mm, 4mm, 6mm, 9mm, or 11mm.

[0082] In some embodiments, the first pipe 3 and / or the second pipe 6 are provided with a resistance-reducing section 601, and the flow cross-sectional area of ​​the resistance-reducing section 601 is larger than the flow cross-sectional area of ​​the remaining parts of the first pipe 3 and / or the second pipe 6. Specifically, the resistance-reducing section 601 can be provided in the first pipe 3, in the second pipe 6, or both in the first pipe 3 and the second pipe 6. When the flow cross-sectional area is the same at each position in the first pipe 3 and / or the second pipe 6, the flow resistance of the coolant in the first pipe 3 and / or the second pipe 6 is uniform. By making the cross-sectional area of ​​the resistance-reducing section 601 larger than the flow cross-sectional area of ​​the remaining parts of the first pipe 3 and / or the second pipe 6, the resistance-reducing section 601 can alleviate the flow resistance of the coolant in the remaining parts of the first pipe 3 and / or the second pipe 6, thereby increasing the flow velocity of the coolant in the first pipe 3 and / or the second pipe 6, and further improving the cooling effect of the coolant on the battery cell 201.

[0083] It should be noted that the flow cross-sectional area refers to the cross-sectional area of ​​a pipe or channel involving fluid flow.

[0084] Furthermore, taking the setting of a resistance-reducing part 601 in the second pipeline 6 as an example, there are multiple resistance-reducing parts 601, and a groove is set between adjacent resistance-reducing parts 601 to avoid the first pipeline 3. This setting can improve the rationality of the layout of the first pipeline 3 and the second pipeline 6, and increase the coverage area of ​​the first pipeline 3 and / or the second pipeline 6 on the cell module 2 within the limited area of ​​the accommodating cavity, so as to improve the cooling effect on the cell 201.

[0085] In some embodiments, in the direction of the height of the cell 201, the outlet of the inlet pipe 4 and the inlet of the return pipe 5 are both lower than the top edge of the cell 201. The length of the inlet pipe 4 extending into the receiving cavity is less than half the height of the cell 201, and the length of the return pipe 5 extending into the receiving cavity is greater than or equal to half the height of the cell 201 and less than the height of the cell 201. Specifically, one end of the inlet pipe 4 extends between adjacent cells 201 or beside the cell 201, and the other end of the inlet pipe 4 is connected to the first conduit 3. One end of the return pipe 5 extends between adjacent cells 201 or beside the cell 201, and the other end of the return pipe 5 is connected to the second conduit 6. Preferably, one end of the inlet pipe 4 extends between adjacent cells 201, and the return pipe 5 extends beside the cell 201 (see [link to relevant documentation]). Figures 3-5In this way, the liquid entering through the inlet pipe 4 can quickly flow to each battery cell 201, thereby achieving precise cooling of the battery cell 201. Furthermore, the outlet of the inlet pipe 4 and the inlet of the return pipe 5 are both lower than the top edge of the battery cell 201, and the size of the inlet pipe 4 is less than half the height of the battery cell 201. Taking the height of the battery cell 201 as H as an example, the outlet of the inlet pipe 4 is located at position 0 to 0.5H of the battery cell 201, while the size of the return pipe 5 is greater than or equal to half the height of the battery cell 201 and less than the height of the battery cell 201. The inlet of the return pipe 5 is located at position 0.5H to H of the battery cell 201, and the outlet of the inlet pipe 4 is lower than the inlet of the return pipe 5. This allows the coolant to cool more parts of the battery cell 201, thereby improving the cooling effect of the coolant on the battery cell 201.

[0086] It should be noted that the height direction of cell 201 refers to... Figure 1 The direction indicated by the double-headed arrow C.

[0087] In addition, the outlet of the liquid inlet pipe 4 can be higher than the top edge of the battery cell 201 or flush with the top edge of the battery cell 201; the liquid inlet pipe 4 can be an inlet opened on the first pipe 3, and the liquid return pipe 5 can be a liquid return hole opened on the second pipe 6. In this case, the first pipe 3 is located at the top of the battery cell module 2, and the second pipe 6 is located at the bottom of the battery cell module 2.

[0088] In some embodiments, the battery pack 15 includes a cover 8, which is integrated with a first conduit 3 and / or a second conduit 6. Specifically, the cover 8 is used to cover the housing 1 on which the cell module 2 is disposed. Here, the first conduit 3 and / or the second conduit 6 are integrated with the cover 8. This configuration can reduce the size of the battery pack 15 in the height direction, thereby increasing the overall energy density of the battery pack 15. Moreover, integrating the cover 8 with the first conduit 3 and / or the second conduit 6 reduces the number of components in the battery pack 15, thereby improving the installation efficiency of the battery pack 15.

[0089] In addition, the first pipe 3 and the second pipe 6 can also be configured in other ways, for example: the bottom plate of the housing 1 is integrated with the first pipe 3 and / or the second pipe 6; one of the first pipe 3 and the second pipe 6 is integrated with the cover 8; and the other of the first pipe 3 and the second pipe 6 is integrated with the bottom plate of the housing 1.

[0090] Furthermore, in some embodiments, multiple inlet pipes 4 and return pipes 5 are provided, and they are all uniformly arranged along the stacking direction of the battery cells 201, and a through flow channel is formed in the gap between adjacent battery cells 201. Specifically, multiple inlet pipes 4 and return pipes 5 are provided. This increases the rate at which coolant flows from the first pipe 3 to the housing 1, and also increases the rate at which coolant flows back to the housing 1 after cooling the battery cells 201, thus increasing the coolant circulation speed. Furthermore, the inlet pipes 4 and return pipes 5 are evenly arranged in the direction of the battery cells 201 stacking. This arrangement ensures that when the coolant enters the housing 1, it is more evenly distributed in the battery cells 201, thereby uniformly cooling the battery cells 201 and further improving the cooling efficiency of the battery cells 201. Moreover, the coolant flows along the evenly arranged inlet pipes 4 to the battery cells 201 located at different positions in the housing 1, enabling the coolant to cool the battery cells 201 at different positions, thereby improving the cooling effect of the battery cells 201. Furthermore, the gaps between adjacent battery cells 201 form flow channels for coolant. The coolant flows within the housing 1, precisely cooling the battery cells 201 during its flow, thus improving cooling efficiency. The return pipe 5 is also evenly arranged along the stacking direction of the battery cells 201, allowing for rapid recovery of the coolant flowing between the cells, thereby improving coolant circulation efficiency.

[0091] It should be noted that the stacking direction of cell 201 is... Figure 1 The direction indicated by the double-headed arrow B.

[0092] Of course, you can also set only one liquid inlet pipe 4 and one liquid return pipe 5, or set multiple liquid inlet pipes 4 and one liquid return pipe 5, or set multiple liquid return pipes 5 and one liquid inlet pipe 4, so as to achieve cooling of the battery cell 201.

[0093] Furthermore, multiple liquid inlet pipes 4 are evenly arranged along the stacking direction of the battery cells 201, and in Figure 1 Two sets of inlet pipes are arranged in the direction of the bidirectional arrow A. Preferably, the inlet pipe 4 is arranged in the middle along the direction shown by the bidirectional arrow A. In this way, the two sets of inlet pipes 4 cool the battery cell module 2 located on both sides of the inlet pipe 4, which further improves the cooling efficiency of the coolant on the battery cell 201.

[0094] In addition, the multiple inlet pipes 4 and multiple return pipes 5 can be arranged in other directions, such as between the bidirectional arrow B and the bidirectional arrow A, or in a direction perpendicular to the stacking of the battery cells 201.

[0095] In some embodiments, the first pipeline 3 includes a connecting portion 301 connected to a plurality of inlet pipes 4, wherein the flow cross-sectional area of ​​the connecting portion 301 is larger than the flow cross-sectional area of ​​the rest of the first pipeline 3. Specifically, the connecting portion 301 is connected to a plurality of inlet pipes 4, preferably the connecting portion 301 is along... Figure 1 The components, arranged in the direction indicated by the bidirectional arrow A, are positioned in the middle of all the battery cell modules 2. This facilitates the cooling of the battery cell 201 by the coolant flowing from the inlet pipe 4. Furthermore, the flow cross-sectional area of ​​the connecting part 301 is larger than that of the rest of the first pipe 3. This allows the connecting part 301 to collect the flow from multiple pipes, thereby ensuring a continuous supply of coolant from the inlet pipe 4 to the housing 1 where the battery cell 201 is located. In addition, the large flow cross-sectional area of ​​the connecting part 301 reduces the flow resistance of the coolant when flowing in the first pipe 3, thereby increasing the flow velocity of the coolant.

[0096] In addition, the second pipeline 6 may also include a reflux section (not shown in the figure) connected to multiple return pipes 5. The flow cross-sectional area of ​​the reflux section is larger than the flow cross-sectional area of ​​the rest of the second pipeline 6. The reflux section has a similar function to the connection section 301 mentioned above, and will not be described again here.

[0097] In some embodiments, the battery pack 15 includes a main inlet 9 connected to the first pipe 3 and a main return port 10 connected to the second pipe 6. The main inlet 9 and the main return port 10 are located on the power-connected side of the housing 1. Specifically, taking the first pipe 3 as the coolant inlet pipe 4 and the second pipe 6 as the coolant return pipe 5 as an example, the main inlet 9 connected to the first pipe 3 and the main return port 10 connected to the second pipe 6 are provided to achieve coolant circulation. Furthermore, the main inlet 9 and the main return port 10 are located on the power-connected side of the housing 1. Since the power-connected side of the battery pack 15 has cable interfaces and other components, this arrangement integrates the main inlet 9 and the main return port 10 with the other power-connected components, making the overall layout more reasonable. It eliminates the need to reserve space for the main inlet 9 and the main return port 10 in other locations, making the layout of the battery pack 15 more streamlined and improving the energy density of the battery pack 15.

[0098] A thermal management system includes a circulation pump 11, a radiator 12, an expansion tank 13, a throttle valve 14, and a battery pack 15 as described above. The circulation pump 11 is connected to a first conduit 3 of the battery pack 15; one end of the radiator 12 is connected to a second conduit 6 of the battery pack 15, and the other end is connected to the circulation pump 11; one end of the expansion tank 13 is connected to the battery pack 15, and the other end is connected to the circulation pump 11; and / or, one end of the expansion tank 13 is connected to the radiator 12, and the other end is connected to the circulation pump 11; the throttle valve 14 is disposed between the expansion tank 13 and the radiator 12, and / or between the expansion tank 13 and the battery pack 15.

[0099] Specifically, the circulation pump 11 is connected to the first pipe 3 of the battery pack 15, or more specifically, the circulation pump 11 is connected to the main inlet 9 via a connecting pipe. It applies pressure to the coolant to direct it to the first pipe 3, and then delivers it through the inlet pipe 4 to the housing 1 containing the battery cells 201. The radiator 12 is connected to both the circulation pump 11 and the second pipe 6. The radiator 12 acts on the coolant flowing from the second pipe 6 to cool it. The coolant is then pressurized by the circulation pump 11 and flows back to the first pipe 3, forming a circulation of coolant flow to cool the battery cells 201 inside the battery pack 15. Furthermore, an expansion tank 13 is installed between the battery pack 15 and the circulation pump 11, and / or between the radiator 12 and the expansion tank 13. The expansion tank 13 discharges gas from the cooling system to facilitate the flow of coolant into the housing 1. Furthermore, a throttle valve 14 is provided between the expansion tank 13 and the radiator 12, and between the expansion tank 13 and the battery pack 15, to control the flow rate of coolant entering the housing 1 and the flow rate of coolant leaving the housing 1, thereby achieving regulation of the coolant flow rate.

[0100] Furthermore, the thermal management system includes the aforementioned battery pack 15. The beneficial effects of the thermal management system brought by the battery pack 15 are described above and will not be repeated here.

[0101] The block diagrams of devices, apparatuses, devices, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0102] It should also be noted that in the apparatus, equipment, and methods of this application, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered as equivalent solutions of this application.

[0103] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0104] It should be understood that the qualifiers “first,” “second,” “third,” “fourth,” “fifth,” and “sixth” used in the description of the embodiments of this application are only used to more clearly illustrate the technical solutions and are not intended to limit the scope of protection of this application.

[0105] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A battery pack, characterized in that, include: The box-shaped enclosure has an internal cavity for receiving contents. A battery cell module includes multiple stacked battery cells, and the battery cell module is installed in the receiving cavity; The first pipeline is in contact with the battery cell module, and the heat exchange medium flows through the first pipeline to exchange heat with the battery cell module. The second pipeline is in contact with the battery cell module, and the heat exchange medium flows through the second pipeline to exchange heat with the battery cell module. The liquid inlet pipe extends at one end to the space between adjacent cells or to the side of the cells. The liquid inlet pipe is used to introduce the heat exchange medium into the housing, and the cells in the housing are in contact with the heat exchange medium. The return pipe extends at one end to the space between adjacent cells or to the side of the cells, and is used to discharge the heat exchange medium inside the housing. The first conduit is connected to the other end of one of the inlet pipe and the return pipe, and the second conduit is connected to the other end of the other of the inlet pipe and the return pipe. In a first direction, the first conduit is disposed on one side of the receiving cavity and covers part of the battery cell module. The second conduit includes a first unit and a second unit disposed on the other side of the receiving cavity and covers the remaining part of the battery cell module, and the first unit is arranged around the first conduit. The first conduit and / or the second conduit are provided with a resistance-reducing section, and the flow cross-sectional area of ​​the resistance-reducing section is larger than the flow cross-sectional area of ​​the remaining parts of the first conduit and / or the second conduit. The second conduit has multiple resistance-reducing sections, and a groove is provided between adjacent resistance-reducing sections to avoid the first conduit. In the direction of the battery cell height, the outlet of the inlet pipe and the inlet of the return pipe are both lower than the top edge of the battery cell.

2. The battery pack according to claim 1, characterized in that, The first pipeline and / or the second pipeline are arranged in a mesh pattern.

3. The battery pack according to claim 1, characterized in that, The first pipeline and / or the second pipeline are disposed on the top of the explosion-proof valve of the battery cell, and at least part of the first pipeline and / or the second pipeline disposed in the explosion-proof valve are heat-fusion pipes.

4. The battery pack according to claim 1, characterized in that, In the second direction, The inlet pipe is located in the middle of the cell module, and at least two return pipes are provided, located at the two ends of the cell module respectively; or, At least two inlet pipes are provided, located at opposite ends of the battery cell module, and the return pipe is located in the middle of the battery cell module; or, The liquid inlet pipe is located at one end of the battery cell module, and the liquid return pipe is located at the other end of the battery cell module.

5. The battery pack according to claim 4, characterized in that, It also includes a crossbeam, which is located in the middle of the housing and divides the receiving cavity into two mounting cavities, and each mounting cavity is respectively equipped with the battery cell module. The liquid inlet pipe is located near the crossbeam, and the liquid return pipe is located at the end of the housing away from the crossbeam.

6. The battery pack according to claim 1, characterized in that, The first conduit and / or the second conduit cover a larger area of ​​the battery cell in the middle of the housing than the area of ​​the battery cell at the end of the housing.

7. The battery pack according to claim 1, characterized in that, The first pipeline and / or the second pipeline have a flat cross-section, the width of the pipeline is b, the height of the pipeline is h, and 10mm≤b≤150mm, 2.5mm≤h<10mm.

8. The battery pack according to claim 1, characterized in that, The length of the inlet pipe extending into the receiving cavity is less than half the height of the battery cell, and the length of the return pipe extending into the receiving cavity is greater than or equal to half the height of the battery cell and less than the height of the battery cell.

9. The battery pack according to claim 1, characterized in that, Includes a cover, which is integrated with the first conduit and / or the second conduit.

10. The battery pack according to claim 1, characterized in that, Multiple inlet pipes and return pipes are provided, and they are evenly arranged along the direction of the battery cell stacking, with a through flow channel formed in the gap between adjacent battery cells.

11. The battery pack according to claim 1, characterized in that, The first pipeline includes a connection portion that connects to the plurality of liquid inlet pipes, and the flow cross-sectional area of ​​the connection portion is larger than the flow cross-sectional area of ​​the rest of the first pipeline.

12. The battery pack according to claim 1, characterized in that, It includes a main liquid inlet connected to the first pipeline and a main liquid return port connected to the second pipeline, wherein the main liquid inlet and the main liquid return port are located on the power-connected side of the housing.

13. A thermal management system, characterized in that, Includes a circulation pump, a radiator, an expansion tank, a throttle valve, and a battery pack as described in any one of claims 1-12, wherein, The circulation pump is connected to the first pipeline of the battery pack; One end of the radiator is connected to the second pipeline of the battery pack, and the other end is connected to the circulation pump; One end of the expansion tank is connected to the battery pack, and the other end is connected to the circulation pump; or, one end of the expansion tank is connected to the radiator, and the other end is connected to the circulation pump. The throttle valve is located between the expansion tank and the radiator, or between the expansion tank and the battery pack.

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