Battery pack

Abstract

The application discloses a battery pack, and belongs to the technical field of batteries. The battery pack comprises a battery module, a box body and an exhaust assembly. The box body is provided with a top wall, a bottom wall and side walls. The top wall and the bottom wall are respectively located on opposite sides of the side walls. The top wall, the bottom wall and the side walls cooperatively enclose a containing cavity. The battery module is located in the containing cavity. The top wall is provided with a gas-permeable hole. The exhaust assembly is arranged on the top wall and located in the containing cavity. The exhaust assembly covers the gas-permeable hole. The exhaust assembly is in airflow communication with the containing cavity and the gas-permeable hole. The gas-permeable hole is used for exhausting the containing cavity by using a gas-permeable piece. The exhaust assembly is arranged in the containing cavity, so that the exhaust assembly is prevented from protruding from the outer surface of the box body, thereby avoiding interference with the installation of the battery pack.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more particularly to a battery pack. Background Technology

[0002] In submersible battery packs, a cooling medium is placed inside the pack, and the battery modules are immersed in the cooling medium, allowing for heat exchange between the cooling medium and the battery modules. In related technologies, to prevent excessive internal pressure in the battery pack, an venting assembly is typically installed on the casing. However, to ensure proper venting, the venting assembly is usually mounted on the outer surface of the casing. This results in the venting assembly protruding from the outer surface of the casing, which can interfere with the installation of the battery pack. Utility Model Content

[0003] One objective of this application is to provide a battery pack that prevents the venting assembly from protruding from the outer surface of the housing, thereby avoiding interference with the installation of the battery pack and at least partially solving the aforementioned technical problems.

[0004] To achieve the above objectives, this application provides a battery pack, comprising: Battery module; The housing has a top wall, a bottom wall, and side walls. The top wall and bottom wall are located on opposite sides of the side walls. The top wall, bottom wall, and side walls work together to enclose a cavity, in which the battery module is located. The top wall is provided with ventilation holes. An exhaust assembly is disposed on the top wall and located within the receiving cavity. The exhaust assembly covers the vent hole, and the airflow of the exhaust assembly connects the receiving cavity and the vent hole.

[0005] Optionally, the exhaust assembly includes a vent, a mounting element, and a seal. The mounting element is connected to the top wall, one side of the seal abuts against the mounting element, and the opposite side of the seal abuts against the top wall. The vent is connected to the mounting element, and the seal is disposed around the outer periphery of the vent.

[0006] Optionally, the mounting element has a first opening, the seal has a second opening, the first opening communicates with the receiving cavity, the second opening communicates with the vent, and the vent is exposed within the first and second openings.

[0007] Optionally, the mounting element has a first opening and a positioning step, the positioning step surrounding the edge of the first opening, at least a portion of the vent extends into the positioning step and is connected to the bottom surface of the positioning step.

[0008] Optionally, the mounting element has a first mounting hole, and the seal has a second mounting hole; The battery pack also includes a first fixing member and a first connecting member. The first fixing member is connected to the housing, and the first connecting member passes through a first mounting hole and a second mounting hole. The first connecting member is connected to the first fixing member, and at least a portion of the first fixing member protrudes from the side of the housing opposite to the receiving cavity; or, The battery pack also includes a second fixing member and a second connecting member. The second fixing member is connected to the housing and passes through the first mounting hole and the second mounting hole. The second connecting member is connected to the second fixing member and the second fixing member protrudes into the receiving cavity.

[0009] Optionally, the enclosure has multiple vent holes, the top wall has a vent section, all vent holes are located in the vent section, and the sealing element surrounds the outer periphery of the vent section.

[0010] Optionally, the battery pack also includes an explosion-proof valve disposed on the side wall, with the explosion-proof valve located at the top of the side wall.

[0011] Optionally, the battery pack includes a cooling assembly, which includes an inlet pipe and a drain pipe communicating with the receiving cavity. The side wall has an inlet and a drain port. The inlet is connected to the inlet pipe, and the drain port is connected to the drain pipe. The horizontal height of the drain port is not lower than the horizontal height of the inlet and the horizontal height of the drain port is not lower than the maximum horizontal height of the battery module.

[0012] Optionally, the battery pack also includes an explosion-proof valve, with the drain outlet at a height not lower than that of the explosion-proof valve.

[0013] Optionally, the battery pack also includes an explosion-proof valve, the opening pressure of which is lower than the rupture pressure of the vent.

[0014] In the battery pack of this application embodiment, the vent hole uses an exhaust assembly to exhaust air from the receiving cavity. By placing the exhaust assembly inside the receiving cavity, the exhaust assembly can be prevented from protruding from the outer surface of the housing, thereby avoiding interference with the installation of the battery pack. Attached Figure Description To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0016] Figure 1 This is a schematic diagram of the overall structure of the battery pack in an exemplary embodiment of this disclosure; Figure 2 yes Figure 1 Sectional view at point AA; Figure 3 yes Figure 1 Exploded view of the battery pack; Figure 4 yes Figure 3 A partial schematic diagram; Figure 5 yes Figure 1 Sectional view at point BB.

[0017] Explanation of reference numerals in the attached figures: 1. Battery module; 2. Box body; 21. Receiving cavity; 22. Vent hole; 23. Top wall; 231. Vent section; 24. Bottom wall; 25. Side wall; 251. Liquid inlet; 252. Liquid outlet; 3. Exhaust assembly; 31. Ventilation element; 32. Mounting element; 321. First opening; 322. Positioning step; 323. Bottom surface of step; 324. First mounting hole; 33. Sealing element; 331. Second opening; 332. Second mounting hole; 4. Cooling components; 41. Liquid inlet pipe; 42. Liquid drain pipe; 5. First fastener; 6. Explosion-proof valve. Detailed Implementation

[0018] 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 a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0019] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0020] See Figure 1 and Figure 2 This application provides a battery pack, including a battery module 1, a housing 2, and an exhaust assembly 3.

[0021] In this embodiment, both the battery module 1 and the exhaust assembly 3 are connected to the housing 2, thus realizing the installation of the battery module 1 and the exhaust assembly 3.

[0022] In some embodiments, in conjunction with reference Figure 3 As shown, the box 2 has a top wall 23, a bottom wall 24 and a side wall 25. The top wall 23 and the bottom wall 24 are located on opposite sides of the side wall 25. The top wall 23, the bottom wall 24 and the side wall 25 work together to enclose the receiving cavity 21.

[0023] In this embodiment, the side wall 25 is connected between the bottom wall 24 and the top wall 23. The bottom wall 24 and the top wall 23 are sealed to the side wall 25, thereby improving the sealing performance of the receiving cavity 21.

[0024] In some embodiments, the battery module 1 is located within the receiving cavity 21.

[0025] In this embodiment, the battery module 1 is placed inside the receiving cavity 21 to avoid the battery module 1 being affected by external environmental factors.

[0026] In some embodiments, the battery pack includes a cooling assembly 4, which includes an inlet pipe 41 and an outlet pipe 42 communicating with the receiving cavity 21.

[0027] In this embodiment, the cooling component 4 includes a cooling source. The cooling source and the receiving cavity 21 can circulate a cooling medium (e.g., liquid) through an inlet pipe 41 and a drain pipe 42. When the cooling medium comes into contact with the battery module 1, it can cool and reduce the temperature of the battery module 1, thus realizing an immersion battery pack.

[0028] In some embodiments, the top wall 23 is provided with ventilation holes 22.

[0029] In this embodiment, after liquid cooling medium is injected into the receiving cavity 21, when the receiving cavity 21 contains gas, the gas will accumulate at the top of the receiving cavity 21, that is, at the top wall 23. The vent 22 is provided on the top wall 23 to facilitate the gas at the top of the receiving cavity 21 to be discharged from the vent 22.

[0030] In some embodiments, the exhaust assembly 3 is disposed on the top wall 23 and covers the vent 22.

[0031] In this embodiment, the exhaust assembly 3 is disposed on the top wall 23, thereby covering the vent 22. After the exhaust assembly 3 covers the vent 22, it can prevent the liquid cooling medium from flowing out of the receiving cavity 21 from the vent 22.

[0032] In some embodiments, the exhaust assembly 3 is in airflow communication with the receiving cavity 21 and the vent 22.

[0033] In this embodiment, the exhaust assembly 3 includes a vent 31. The vent 31 provides airflow communication between the receiving cavity 21 and the vent hole 22.

[0034] In this embodiment, the exhaust assembly 3 (e.g., the vent 31) can only achieve airflow communication between the receiving cavity 21 and the vent 22, while the liquid cooling medium is difficult to pass through the exhaust assembly 3 (e.g., the vent 31), that is, the liquid cooling medium is difficult to flow out of the receiving cavity 21 from the vent 22, thereby avoiding the loss of cooling medium as much as possible.

[0035] In this embodiment, after the exhaust component 3 (e.g., the vent 31) achieves airflow communication between the receiving cavity 21 and the vent 22, the receiving cavity 21 and the external environment of the battery pack are balanced, thus avoiding the pressure difference between the battery pack and the external environment from affecting the normal operation of the battery pack.

[0036] In some embodiments, the exhaust assembly 3 is located within the receiving cavity 21.

[0037] In this embodiment, the exhaust assembly 3 is located inside the receiving cavity 21, which can prevent the exhaust assembly 3 from being affected by external environmental factors and ensure the safety of the exhaust assembly 3.

[0038] In this embodiment, the vent 22 uses the exhaust assembly 3 (i.e., the vent 31) to exhaust the cavity 21. By placing the exhaust assembly 3 inside the cavity 21, the exhaust assembly 3 can be prevented from protruding from the outer surface of the housing 2, thereby avoiding interference with the installation of the battery pack.

[0039] In some embodiments, in conjunction with reference Figure 2 and Figure 3 As shown, the exhaust assembly 3 includes a mounting member 32 and a sealing member 33.

[0040] In this embodiment, both the mounting component 32 and the sealing component 33 are located within the receiving cavity 21, preventing them from protruding from the outer surface of the housing 2 and thus avoiding interference with the installation of the battery pack. Furthermore, this also prevents the mounting component 32 and the sealing component 33 from being affected by external environmental factors, improving their safety.

[0041] In some embodiments, the mounting element 32 is connected to the top wall 23.

[0042] In this embodiment, the mounting component 32 can be detachably connected to the top wall 23, for example, by bolting, to facilitate the installation of the exhaust assembly 3.

[0043] In some embodiments, one side of the seal 33 abuts against the mounting member 32, and the opposite side of the seal 33 abuts against the top wall 23.

[0044] In this embodiment, after the mounting component 32 is connected to the top wall 23, the sealing component 33 abuts against the mounting component 32 and the top wall 23 to seal the space between the mounting component 32 and the top wall 23.

[0045] In some embodiments, the vent 31 is connected to the mounting member 32.

[0046] In this embodiment, the breathable component 31 and the mounting component 32 are sealed together, for example, the breathable component 31 is bonded to the mounting component 32.

[0047] In some embodiments, the seal 33 is disposed around the outer periphery of the gas permeable member 31.

[0048] In this embodiment, after the gas permeable member 31 is connected to the mounting member 32, the seal 33 is arranged around the peripheral edge of the gas permeable member 31, which can seal the peripheral edge of the gas permeable member 31 and prevent the liquid cooling medium from flowing out through the gas vent 22.

[0049] In some embodiments, with further reference to Figure 3 and Figure 4 as shown, the mounting member 32 has a first opening 321.

[0050] In this embodiment, the mounting member 32 has a "loop" shaped structure.

[0051] In some embodiments, the seal 33 has a second opening 331.

[0052] In this embodiment, the seal 33 has a "loop" shaped structure.

[0053] In some embodiments, with further reference to Figure 2 as shown, the first opening 321 is in communication with the receiving cavity 21.

[0054] In this embodiment, the first opening 321 is in communication with the receiving cavity 21, so that air flow communication can be achieved between the receiving cavity 21 and the first opening 321.

[0055] In some embodiments, the second opening 331 is in communication with the gas vent 22.

[0056] In this embodiment, the second opening 331 is in communication with the gas vent 22, so that air flow communication can be achieved between the gas vent 22 and the second opening 331.

[0057] In some embodiments, the gas permeable member 31 is exposed inside the first opening 321 and the second opening 331.

[0058] In this embodiment, one side (for example, the lower side) of the gas permeable member 31 is exposed toward the receiving cavity 21 through the first opening 321, and the opposite side (for example, the upper side) of the gas permeable member 31 is exposed toward the gas vent 22 through the second opening 331, so that air flow communication can be achieved between the receiving cavity 21 and the gas vent 22 via the gas permeable member 31.

[0059] Exemplarily, when the receiving cavity 21 has a positive pressure relative to the external environment, the gas in the receiving cavity 21 sequentially passes through the first opening 321, the gas permeable member 31, and the second opening 331, and then flows from the gas vent 22 to the external environment. When the receiving cavity 21 has a negative pressure relative to the external environment, the gas in the external environment sequentially passes through the second opening 331, the gas permeable member 31, and the first opening 321, and then flows into the receiving cavity 21.

[0060] Exemplarily, the mounting member 32 may be a plastic part or a sheet metal part, that is, the material of the mounting member 32 may be plastic or metal. The material of the sealing member 33 may be an oil-resistant rubber material, such as an acrylate rubber material.

[0061] In some embodiments, with further reference to Figure 4 as shown, the mounting member 32 is provided with a positioning step 322, and the positioning step 322 is disposed around the edge of the first opening 321.

[0062] In this embodiment, the positioning step 322 is disposed along the peripheral edge of the first opening 321, that is, it is a closed structure in the shape of a Chinese character "kou".

[0063] In some embodiments, at least part of the gas permeable member 31 extends into the positioning step 322.

[0064] In this embodiment, the gas permeable member 31 achieves positioning and docking with the mounting member 32 by extending into the positioning step 322.

[0065] In some embodiments, the gas permeable member 31 is connected to the step bottom surface 323 of the positioning step 322.

[0066] In this embodiment, the gas permeable member 31 is bonded to the step bottom surface 323, which improves the sealing performance of the gas permeable member 31 at the edge of the first opening 321, thereby improving the sealing performance between the gas permeable member 31 and the mounting member 32.

[0067] Exemplarily, with further reference to Figure 2 as shown, one side of the gas permeable member 31 is connected to the step bottom surface 323 of the positioning step 322, and the opposite side of the gas permeable member 31 abuts against the sealing member 33, ensuring the sealing performance at the peripheral edge of the gas permeable member 31.

[0068] In some embodiments, with further reference to Figure 4 as shown, the mounting member 32 is provided with a first mounting hole 324, and the sealing member 33 is provided with a second mounting hole 332.

[0069] In this embodiment, the first mounting holes 324 are in one-to-one correspondence with the second mounting holes 332.

[0070] In some embodiments, with reference to Figure 5 as shown, the battery pack further comprises a first fixing member 5 and a first connecting member (not shown in the figure).

[0071] In some embodiments, the first fixing member 5 is connected to the box body 2.

[0072] In this embodiment, the first fixing member 5 and the box body 2 are welded to each other, which improves the connection strength between the two.

[0073] In some embodiments, the first connector passes through the first mounting hole 324 and the second mounting hole 332.

[0074] In this embodiment, by inserting the first connector through the first mounting hole 324 and the second mounting hole 332, the offset of the mounting member 32 and the sealing member 33 along the radial direction of the first connector can be limited, thereby improving the installation strength and mechanical reliability of the vent member 31. This prevents the vent member 31 from falling off due to vibration, and consequently prevents the liquid cooling medium from leaking from the vent hole 22.

[0075] In some embodiments, the first connector is connected to the first fastener 5.

[0076] In this embodiment, the first fixing member 5 is detachably connected to the first connecting member, for example, by a threaded connection. After the first connecting member is connected to the first fixing member 5, the first connecting member abuts against the side of the mounting member 32 away from the seal member 33, which can limit the offset of the mounting member 32 and the seal member 33 along the axial direction of the first connecting member.

[0077] In some embodiments, at least a portion of the first fastener 5 protrudes from the side of the housing 2 away from the receiving cavity 21.

[0078] In this embodiment, the first fixing member 5 protrudes from the outer surface of the housing 2, which avoids the first fixing member 5 occupying the internal space of the receiving cavity 21, and also avoids the first fixing member 5 being too close to the battery module 1, thus improving the safety of the battery pack.

[0079] For example, such as Figure 5 The first fixing member 5 has an internal thread, and the first connecting member can be a bolt, thereby realizing the threaded connection between the first fixing member 5 and the first connecting member.

[0080] In other embodiments, threaded holes (e.g., blind holes) can be made on the housing 2 to directly connect the first connector to the threaded hole, thereby eliminating the need for the first fastener 5.

[0081] In some embodiments not shown, the battery pack further includes a second fastener and a second connector.

[0082] In some embodiments not shown, the second fastener is connected to the housing 2.

[0083] In this embodiment, the second fastener is welded to the housing 2, which improves the connection strength between the two.

[0084] In some embodiments not shown, the second fastener passes through the first mounting hole 324 and the second mounting hole 332.

[0085] In this embodiment, by inserting the second fastener through the first mounting hole 324 and the second mounting hole 332, the offset of the mounting member 32 and the sealing member 33 along the radial direction of the second fastener can be limited, thereby improving the installation strength and mechanical reliability of the vent member 31. This prevents the vent member 31 from falling off due to vibration, and consequently prevents the liquid cooling medium from leaking from the vent hole 22.

[0086] In some embodiments not shown, the second connector is connected to the second fastener.

[0087] In this embodiment, the second fixing member and the second connecting member are detachably connected, for example, by a threaded connection. After the second fixing member and the second connecting member are connected, the second connecting member abuts against the side of the mounting member 32 away from the seal member 33, which can limit the offset of the mounting member 32 and the seal member 33 along the axial direction of the second fixing member.

[0088] In some embodiments not shown, the second fastener protrudes toward the receiving cavity 21.

[0089] In this embodiment, the second fixing member protrudes into the receiving cavity 21, reducing the protrusion on the surface of the housing 2 and improving the convenience of battery pack installation.

[0090] For example, the second fastener has external threads, such as a bolt. The second connector has internal threads, such as a nut.

[0091] In some embodiments, continue to refer to Figure 3 and Figure 4 As shown, the box body 2 has multiple ventilation holes 22, and the top wall 23 has a ventilation section 231. All ventilation holes 22 are located in the ventilation section 231.

[0092] In this embodiment, the vent 22 is provided on the top wall 23 (e.g., the vent 231) to facilitate the emptying of the gas inside the receiving cavity 21.

[0093] In this embodiment, the arrangement of multiple vent holes 22, compared to a single vent hole with the same area, satisfies the air permeability requirement while improving the structural strength of the housing 2 (e.g., the top wall 23), ensuring the strength requirements of the housing 2. Therefore, during the storage or use of the battery pack, if bolts or foreign objects fall into the vent holes 22, they will not puncture the venting element 31 covering the vent holes 22.

[0094] In this embodiment, the vent 22 is provided on the top wall 23 (e.g., the vent 231), and the exhaust assembly 3 is located in the receiving cavity 21. This reduces the protrusion on the outer surface of the top wall 23, thereby reducing the space occupied by the battery pack in the vertical direction and saving the space occupied by the battery pack in the Z direction of the vehicle.

[0095] In this embodiment, multiple vent holes 22 are evenly arranged on the vent 231 to achieve uniform exhaust while improving the strength of the vent 231 and ensuring the structural strength of the top wall 23.

[0096] For example, the vent 231 is positioned on the top wall 23 to avoid the pressure relief valve on the top of the battery cell, thus preventing damage to the vent 31 when the pressure relief valve releases pressure and improving the safety of the battery pack.

[0097] In some embodiments, the seal 33 surrounds the outer periphery of the vent 231.

[0098] In this embodiment, the sealing element 33 surrounds the periphery of all the vent holes 22 (i.e., the vent portion 231), thereby enabling a single vent element 31 to shield all the vent holes 22 and ensure the sealing of the periphery of the vent portion 231, preventing liquid cooling medium from flowing out of the vent holes 22.

[0099] For example, the horizontal height of the sidewall 25 is higher than the horizontal height of the battery module 1, ensuring that the battery module 1 is completely submerged in the liquid cooling medium.

[0100] In some embodiments, continue to refer to Figure 1 and Figure 3 As shown, the battery pack also includes an explosion-proof valve 6, which is disposed on the side wall 25.

[0101] In this embodiment, the explosion-proof valve 6 is installed on the side wall 25 to prevent hot gas and particulate matter from being ejected upwards into the passenger compartment during thermal runaway, thereby reducing the danger of battery pack thermal runaway.

[0102] In this embodiment, since the vent 22 is located on the top wall 23 and the explosion-proof valve 6 is located on the side wall 25, the explosion-proof valve 6 is lower than the vent 22. Even if the vent 31 breaks, the liquid cooling medium can only be discharged from the explosion-proof valve 6 and cannot be discharged from the vent 22.

[0103] In some embodiments, the explosion-proof valve 6 is located on top of the sidewall 25.

[0104] In this embodiment, the explosion-proof valve 6 is located at the top of the side wall 25, which can reduce the loss of liquid cooling medium during thermal runaway, thereby using the cooling medium to cool down and extinguish the fire during thermal runaway.

[0105] In some embodiments, continue to refer to Figure 1 and Figure 3 As shown, the side wall 25 has a liquid inlet 251 and a liquid outlet 252. The liquid inlet 251 is connected to the liquid inlet pipe 41, and the liquid outlet 252 is connected to the liquid outlet pipe 42.

[0106] For example, the inlet 251 and the outlet can be located on the same side of the side wall 25, and the explosion-proof valve 6 can be located on the other side of the side wall 25.

[0107] In some embodiments, the horizontal height of the drain port 252 is not lower than the horizontal height of the inlet port 251.

[0108] In this embodiment, the horizontal height of the drain port 252 is higher than that of the inlet port 251, realizing the bottom liquid inlet and top liquid outlet of the receiving cavity 21. This allows the liquid cooling medium to be filled to a certain height before being discharged from the drain port 252, increasing the heat exchange time between the liquid cooling medium and the battery module 1 and ensuring sufficient heat exchange between the battery module 1 and the cooling medium.

[0109] In this embodiment, since the vent 22 is located on the top wall 23 and the drain port 252 is located on the side wall 25, the drain port 252 is lower than the vent 22. Thus, when the cooling component 4 circulates the cooling medium with the receiving cavity 21, it can exhaust the gas in the receiving cavity 21, thereby avoiding surge impact caused by the presence of gas in the receiving cavity 21.

[0110] In some embodiments, the horizontal height of the drain port 252 is not lower than the maximum horizontal height of the battery module 1.

[0111] In this embodiment, the horizontal height of the drain port 252 is higher than the maximum horizontal height of the battery module 1, ensuring that the liquid cooling medium completely submerges the battery module 1, and that sufficient heat exchange can occur between the battery module 1 and the cooling medium.

[0112] In some embodiments, the horizontal height of the drain port 252 is not lower than the horizontal height of the explosion-proof valve 6.

[0113] In this embodiment, the horizontal height of the drain port 252 is higher than that of the explosion-proof valve 6, which facilitates the emptying of the gas in the containment cavity 21 and reduces the accumulation of gas at the top of the containment cavity 21.

[0114] In this embodiment, after the explosion-proof valve 6 has finished draining the liquid, the liquid level in the receiving cavity 21 is lower than the drain port 252. It is necessary to close the explosion-proof valve 6 and re-inject the cooling medium in order to achieve the circulation of the cooling medium. This avoids the circulation of the cooling medium without closing the explosion-proof valve 6, and ensures that the cooling medium circulates while the receiving cavity 21 is sealed, thereby improving the safety of the battery pack.

[0115] In some embodiments, the opening pressure of the explosion-proof valve 6 is lower than the rupture pressure of the vent 31.

[0116] In this embodiment, the pressure resistance of the venting component 31 is much higher than the burst pressure of the explosion-proof valve 6. Utilizing the pressure difference between the venting component 31 and the explosion-proof valve 6, the explosion-proof valve 6 first opens to drain liquid and vent gas, and then the gas is released through the venting component 31. Then, the explosion-proof valve 6 is closed, the cooling assembly 4 is turned on to circulate and dissipate heat from the cooling medium, and the remaining gas is discharged through the venting component 31, achieving a stepped, segmented improvement in safety performance during thermal runaway.

[0117] For example, when thermal runaway occurs in battery module 1, the venting rate of the vent 31 is lower than the gas generation rate of thermal runaway, causing a sharp increase in pressure within the containment cavity 21. When the pressure reaches the burst pressure of the explosion-proof valve 6, the explosion-proof valve 6 opens to release pressure. Since the pressure release rate of the explosion-proof valve 6 is greater than the gas generation rate of thermal runaway, the hot gas in the containment cavity 21 is rapidly discharged from the explosion-proof valve 6, causing the pressure within the containment cavity 21 to decrease. During this process, the vent 31 does not reach the burst pressure, thus maintaining normal operation.

[0118] For example, during the depressurization process of the explosion-proof valve 6, since the explosion-proof valve 6 is located at the top of the side wall 25, when the liquid level in the receiving cavity 21 drops below the explosion-proof valve 6, the liquid cooling medium will no longer be discharged. The gas in the receiving cavity 21 can continue to be discharged through the explosion-proof valve 6.

[0119] For example, when the pressure inside the containment cavity 21 drops to the closing value of the explosion-proof valve 6, the explosion-proof valve 6 closes, thereby stopping the pressure relief. The remaining gas inside the containment cavity 21 can continue to slowly discharge through the vent 31 at the top. At this time, the cooling assembly 4 controls the circulation of the cooling medium. After circulating inside the containment cavity 21, the cooling medium dissipates heat, ensuring the safety of the battery pack. Furthermore, opening the cooling assembly 4 after the explosion-proof valve 6 stops depressurizing avoids the cooling assembly 4 being affected by the impact of high-temperature, high-pressure gas, thus preventing the cooling medium from leaking from the explosion-proof valve 6 during the pressure relief process. Opening the cooling assembly 4 when the explosion-proof valve 6 is closed reduces the leakage of the cooling medium inside the containment cavity 21. For example, the explosion-proof valve 6 can be spring-loaded and selectively open and close according to the pressure inside the receiving cavity 21.

[0120] For example, the cooling medium can be an insulating oil-based liquid, such as a hydrocarbon, ether, or ester liquid.

[0121] For example, the breathable component 31 can be a membrane structure with good mechanical properties, such as tensile strength and high tensile strength. The breathable component 31 can be made of oil-resistant material, such as polytetrafluoroethylene (PTFE), which can be expanded polytetrafluoroethylene (ePTFE).

[0122] For example, the vent 31 can effectively prevent external air, salt spray, dust and other substances from entering the receiving cavity 21, and can also prevent the liquid cooling medium in the receiving cavity 21 from permeating outward.

[0123] For example, the vent 31 can also quickly balance the pressure gradient (i.e., the pressure difference between the battery pack and the external environment) caused by changes in temperature, environment, and altitude. For instance, when the internal pressure of the receiving cavity 21 is high, gas can be vented outward through the vent 31. This achieves safe venting and balances the internal pressure of the battery pack, preventing damage to components caused by pressure fluctuations. Furthermore, balancing the internal pressure of the battery pack also avoids thermal expansion problems. When the housing 2 expands or contracts with temperature changes, causing pressure fluctuations, gas can be promptly discharged, preventing leakage or damage to the cooling medium and improving the safety and reliability of the system.

[0124] For example, the vent 31 prevents the cooling medium from leaking to the outside of the battery pack during the exhaust process, reducing the risk of safety hazards and environmental pollution. Utilizing the slow-permeability of the vent 31, the gas inside the containment cavity can be discharged from the vent 22 by the injection pressure of the cooling assembly 4.

[0125] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0126] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0127] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0128] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A battery pack, characterized in that, include: Battery module; The housing has a top wall, a bottom wall, and side walls. The top wall and the bottom wall are located on opposite sides of the side walls. The top wall, the bottom wall, and the side walls cooperate to form a receiving cavity. The battery module is located in the receiving cavity. The top wall is provided with ventilation holes. An exhaust assembly is disposed on the top wall and located within the receiving cavity, the exhaust assembly covers the vent hole, and the exhaust assembly provides airflow communication between the receiving cavity and the vent hole.

2. The battery pack as described in claim 1, characterized in that, The exhaust assembly includes a venting component, a mounting component, and a sealing component. The mounting component is connected to the top wall, one side of the sealing component abuts against the mounting component, and the opposite side of the sealing component abuts against the top wall. The venting component is connected to the mounting component, and the sealing component is disposed around the outer periphery of the venting component.

3. The battery pack as described in claim 2, characterized in that, The mounting element has a first opening, the sealing element has a second opening, the first opening communicates with the receiving cavity, the second opening communicates with the vent hole, and the vent element is exposed within the first opening and the second opening.

4. The battery pack as described in claim 2, characterized in that, The mounting member has a first opening and a positioning step, the positioning step surrounding the edge of the first opening, at least a portion of the vent extends into the positioning step and is connected to the bottom surface of the positioning step.

5. The battery pack as described in claim 2, characterized in that, The mounting element has a first mounting hole, and the sealing element has a second mounting hole; The battery pack further includes a first fixing member and a first connecting member. The first fixing member is connected to the housing, and the first connecting member passes through the first mounting hole and the second mounting hole. The first connecting member is connected to the first fixing member, and at least a portion of the first fixing member protrudes from the side of the housing opposite to the receiving cavity; or, The battery pack also includes a second fixing member and a second connecting member. The second fixing member is connected to the housing and passes through the first mounting hole and the second mounting hole. The second connecting member is connected to the second fixing member and the second fixing member protrudes into the receiving cavity.

6. The battery pack as described in claim 2, characterized in that, The housing has multiple vent holes, the top wall has a vent section, all the vent holes are located in the vent section, and the sealing element surrounds the outer periphery of the vent section.

7. The battery pack as described in claim 1, characterized in that, The battery pack also includes an explosion-proof valve, which is disposed on the side wall and located at the top of the side wall.

8. The battery pack as claimed in claim 1, characterized in that, The battery pack also includes a cooling assembly, which includes an inlet pipe and an outlet pipe communicating with the receiving cavity. The side wall has an inlet port and an outlet port. The inlet port is connected to the inlet pipe, and the outlet port is connected to the outlet pipe. The horizontal height of the outlet port is not lower than the horizontal height of the inlet port, and the horizontal height of the outlet port is not lower than the maximum horizontal height of the battery module.

9. The battery pack as described in claim 8, characterized in that, The battery pack also includes an explosion-proof valve, and the horizontal height of the drain port is not lower than the horizontal height of the explosion-proof valve.

10. The battery pack as claimed in claim 2, characterized in that, The battery pack also includes an explosion-proof valve, the opening pressure of which is lower than the rupture pressure of the venting element.

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