Venting assembly, battery module, and battery pack

Abstract

The present application discloses a venting assembly, comprising: a venting member, a plurality of gas guide members, and a plurality of gas baffles. The gas guide members are arranged in a venting cavity of the venting member and correspond to gas inlets; the gas baffles are arranged at exits of the gas guide members; when the gas baffles are at a first position, the gas baffles block openings of the corresponding gas guide members; when the gas baffles are at a second position, the gas baffles unblock the openings of the corresponding gas guide members, and the gas baffles cut off a flow path of the venting cavity. The venting assembly of the present application aims to solve the problem that high-temperature substances in venting assemblies are prone to accumulation during thermal runaway of cells, and achieves constraint and guidance of flow of the high-temperature substances and gas to specified directions, so that the high-temperature substances and gas are rapidly vented and are not prone to accumulation, thereby avoiding further thermal runaway of adjacent cells. The present application also discloses a battery module and a battery pack.

Description

An exhaust assembly, a battery module, and a battery pack.

[0001] This application claims priority to Chinese Patent Application No. 202411991992.9, filed with the Chinese Patent Office on December 31, 2024, entitled “An Exhaust Assembly, a Battery Module and a Battery Pack”, the entire contents of which are incorporated herein by reference.

[0002] Technical Field

[0003] This application relates to the field of battery technology, and in particular to an exhaust assembly, a battery module, and a battery pack. Background Technology

[0004] Battery modules typically consist of multiple cells. When a cell experiences thermal runaway, it generates a large amount of high-temperature gas and substances, which can even cause a fire in severe cases. To ensure safety, a venting assembly is required within the battery module. This assembly can expel the high-temperature gas to the outside environment when a cell experiences thermal runaway, thereby reducing the internal temperature of the battery module and preventing heat spread, thus avoiding thermal runaway in more adjacent cells.

[0005] For example, Chinese patent CN2022103325014 uses an exhaust assembly to discharge high-temperature gas through a unified second channel, and also sets up a one-way valve to isolate the gas, making it less likely for other cells to affect thermal runaway. However, its guiding performance is poor, and high-temperature substances tend to accumulate in the exhaust assembly, especially in the area near the sealing end of the exhaust assembly, so its thermal runaway management is still not perfect. Technical solutions

[0006] This application provides an exhaust assembly designed to address the problem of high-temperature substances accumulating inside the exhaust assembly when a battery cell experiences thermal runaway. It utilizes a built-in air guide to divert the flow and an exhaust baffle to cut off the flow path of the exhaust chamber, thereby constraining and guiding the flow of high-temperature substances and gases in a designated direction. This allows the high-temperature substances and gases to be discharged quickly and prevents them from accumulating, thus avoiding further thermal runaway in adjacent battery cells.

[0007] The technical solution adopted in this application to solve its problem is:

[0008] An exhaust assembly for use in a battery module comprising multiple battery cells, comprising:

[0009] The exhaust component has an exhaust chamber inside it. The exhaust component is also provided with at least one exhaust outlet hole communicating with the exhaust chamber and multiple exhaust inlets communicating with the exhaust chamber. The multiple exhaust inlets are arranged sequentially in the direction toward the exhaust outlet hole. Each exhaust inlet is configured to introduce high-temperature substances and gases discharged from the battery cell.

[0010] Multiple air guides are provided in the exhaust chamber. At least some exhaust inlets are provided with air guides. The air guides open in the direction of the exhaust outlet and connect the corresponding exhaust inlets to the exhaust chamber.

[0011] Multiple exhaust baffles are movably disposed at the opening of the air guide component. The exhaust baffles have a first position and a second position. When the exhaust baffle is in the first position, the exhaust baffle blocks the opening of the corresponding air guide component. High-temperature substances and gases flowing from the air guide component to the exhaust chamber can drive the corresponding exhaust baffle to switch from the first position to the second position. When the exhaust baffle is in the second position, the exhaust baffle opens the opening of the corresponding air guide component and cuts off the flow path of the exhaust chamber.

[0012] The second aspect of this application provides a battery module comprising multiple battery cells and the above-mentioned venting assembly, wherein the explosion-proof valve of each battery cell corresponds to a venting inlet of the venting assembly.

[0013] A third aspect of this application provides a battery pack that incorporates the battery module described above. Beneficial effects

[0014] Implementing this application will have the following beneficial effects:

[0015] When a cell experiences thermal runaway, high-temperature substances and gases are introduced through the corresponding exhaust inlet. These substances and gases push the corresponding exhaust baffle to a second position, opening the outlet of the gas guide. The gas guide leads the high-temperature substances and gases into the exhaust chamber and rapidly flows towards the exhaust outlet. The exhaust baffle cuts off the flow path within the exhaust chamber, ensuring the high-temperature gas can only flow forward (towards the exhaust outlet), thus preventing it from affecting the normal cells downstream. Furthermore, during the forward flow of the high-temperature substances and gases, the exhaust baffle at the front end is in its first position, preventing them from flowing into the front exhaust inlet and affecting the normal cells there. This prevents the high-temperature substances and gases from flowing into other exhaust inlets, protecting other cells from their influence. Additionally, the rapid outward discharge of high-temperature gas carries away high-temperature substances, preventing accumulation and further thermal runaway. Other beneficial effects will be illustrated in the specific embodiments. Attached Figure Description

[0016] Figure 1 is a schematic diagram of the structure of the battery module according to an embodiment of this application;

[0017] Figure 2 is an exploded view of the exhaust assembly according to an embodiment of this application;

[0018] Figure 3 is a magnified view of part A shown in Figure 2;

[0019] Figure 4 is one of the schematic diagrams of the working state of the exhaust assembly according to an embodiment of this application;

[0020] Figure 5 is a second schematic diagram of the working state of the exhaust assembly according to an embodiment of this application;

[0021] Figure 6 is a partial enlarged cross-sectional view of the exhaust assembly according to an embodiment of this application.

[0022] Implementation methods of this application

[0023] Referring to Figures 1 and 2, this application discloses an exhaust assembly 100 applied in a battery module. The battery module includes the exhaust assembly 100 and multiple battery cells 200. Each battery cell 200 is equipped with an explosion-proof valve 201. The exhaust assembly 100 collects and guides the high-temperature substances and gases ejected from the battery cell 200 during thermal runaway, preventing further thermal runaway and aiming to solve the problem of high-temperature substances easily accumulating inside the exhaust assembly 100 when the battery cell 200 experiences thermal runaway. This application also discloses a battery pack using this battery module.

[0024] In this embodiment, the exhaust assembly 100 includes an exhaust component 1, multiple air guides 2, and multiple exhaust baffles 3. An exhaust chamber 13 is formed within the exhaust component 1. The exhaust component 1 is also provided with at least one exhaust outlet 14 communicating with the exhaust chamber 13 and multiple exhaust inlets 15 communicating with the exhaust chamber 13. The multiple exhaust inlets 15 are arranged sequentially in the direction towards the exhaust outlet 14. The explosion-proof valve 201 of each battery cell 200 corresponds to a specific exhaust inlet 15. Each exhaust inlet 15 is configured to introduce high-temperature substances and gases discharged from the battery cell 200. Air guides 2 are disposed within the exhaust chamber 13, with at least some exhaust inlets 15 corresponding to air guides 2. The air guides 2 open towards the exhaust outlet 14, connecting the corresponding exhaust inlets 15 to the exhaust chamber 13. The openings of the multiple air guides 2 face the same direction. All of them face the exhaust outlet 14, so that the high-temperature substances and gases in the exhaust chamber 13 flow in the same direction, avoiding backflow and improving flow smoothness and safety. The exhaust baffle 3 is movably disposed at the opening of the air guide 2. The exhaust baffle 3 has a first position and a second position. When the exhaust baffle 3 is in the first position, the exhaust baffle 3 blocks the opening of the corresponding air guide 2, and the exhaust baffle 3 plays a protective role. The high-temperature substances and gases flowing from the air guide 2 to the exhaust chamber 13 can drive the corresponding exhaust baffle 3 to switch from the first position to the second position. When the exhaust baffle is in the second position, the exhaust baffle 3 opens the opening of the corresponding air guide 2 and cuts off the flow path of the exhaust chamber 13, so that the high-temperature substances and gases can only flow to the exhaust outlet 14 and cannot flow to the closed end.

[0025] The outer side of the exhaust component 1 is provided with multiple protrusions 16, each protrusion 16 corresponding to an exhaust inlet 15. Each protrusion 16 is designed to fit against the outer periphery of the explosion-proof valve 201 of the battery cell 200 to better guide the high-temperature substances and gases discharged from the battery cell 200 and reduce the risk of leakage. Of course, the connection between the exhaust component 100 and the explosion-proof valve 201 of the battery cell 200 can also adopt other methods such as indirect connection, which are not limited here.

[0026] As a specific example, referring to Figure 2, and in conjunction with Figures 4 and 5, the exhaust component 1 is roughly elongated, with one end closed and the other end having an exhaust outlet 14. There are thirteen exhaust inlets 15, arranged sequentially along the length of the exhaust component 1. There are twelve air guides 2 and twelve exhaust baffles 3, with the air guide 2 and exhaust baffle 3 not located at the exhaust inlet 15 closest to the closed end. It should be noted that the number of air guides 2 and exhaust baffles 3 can be less than or equal to the number of exhaust inlets 15; this is not limited here. Furthermore, the number of air guides 2, exhaust baffles 3, and exhaust inlets 15 can be chosen in other ways as needed. The exhaust inlets 15 and exhaust outlets 14 can be any shape, such as circular, elliptical, rectangular, or rhomboid. This application does not limit the specific shape of the exhaust inlets 15 or the exhaust outlets 14.

[0027] Referring to Figure 4 or Figure 5 and taking the direction shown in Figure 4 or Figure 5 as reference, the sealing end is located on the left (defined as the rear end), the exhaust outlet 14 is located on the right (defined as the front end), the multiple exhaust inlets 15 are defined from left to right as exhaust inlet No. 1, exhaust inlet No. 2, ..., exhaust inlet No. N, the multiple air guides 2 are defined from left to right as air guide No. 1, air guide No. 2, ..., air guide No. M, and the multiple exhaust baffles 3 are defined from left to right as exhaust baffle No. 1, exhaust baffle No. 2, ..., exhaust baffle No. M. During use, for example, as shown in Figure 4, when the cell 200 corresponding to the second exhaust inlet experiences thermal runaway, high-temperature substances and gases are introduced from the second exhaust inlet. The high-temperature substances and gases push the first exhaust baffle to the second position to open the outlet of the first air guide. The first exhaust baffle also cuts off the flow path of the exhaust chamber 13. The first air guide guides the high-temperature substances and gases into the exhaust chamber 13 and quickly flows towards the exhaust outlet 14 (i.e., towards the front end). Since the first exhaust baffle cuts off the flow path of the exhaust chamber 13 and blocks the channel to the sealing end, the high-temperature substances and gases cannot flow and accumulate towards the first exhaust inlet (i.e., cannot flow towards the rear end), thus not affecting the normal cell 200 near the sealing end of the exhaust component 1. During the process of the high-temperature substances and gases flowing towards the front end, the second to M exhaust baffles located on the right side of the second exhaust inlet are in the first position, which can prevent the high-temperature substances and gases from flowing from the third exhaust inlet to the N exhaust inlet and affecting the normal cell 200 near the exhaust outlet 14. During use, for example as shown in Figure 5, when the cell 200 corresponding to the first exhaust port experiences thermal runaway, high-temperature substances and gases are introduced from the first exhaust port. Since the first exhaust port is closest to the sealing end, the high-temperature substances and gases can quickly flow towards the exhaust port 14 (i.e., towards the front end). During the process of the high-temperature substances and gases flowing towards the front end, all the exhaust baffles 3 located on the right side of the first exhaust port are in the first position, which can prevent the high-temperature substances and gases from flowing from the second exhaust port to the Nth exhaust port and affecting other normal cells 200.

[0028] Thus, the exhaust assembly 100 provided in this application uses the built-in air guide 2 for air diversion and the exhaust baffle 3 to cut off the flow path of the exhaust chamber 13, thereby constraining and guiding the flow of high-temperature substances and gases in a specified direction. This can prevent high-temperature substances and gases from flowing to other exhaust inlets 15 and protect other battery cells 200 from the influence of high-temperature substances and gases. Furthermore, when high-temperature gases are rapidly discharged outward, they can carry high-temperature substances with them and discharge them quickly, preventing accumulation and avoiding further thermal runaway.

[0029] Understandably, in other preferred embodiments, the exhaust component 1 may also be provided with two exhaust outlets 14, which are respectively provided at both ends of the exhaust component 1. In this case, the air guide 2 at part of the exhaust inlet 15 opens toward one of the exhaust outlets 14, and the air guide 2 at the other part of the exhaust inlet 15 opens toward the other exhaust outlet 14. Alternatively, the exhaust chamber 13 may be provided with multiple exhaust chambers, each exhaust chamber 13 having an exhaust outlet 14 and multiple exhaust inlets 15, forming a unidirectional flow path in each exhaust chamber 13.

[0030] To further improve the flow guiding and sealing effects, in some embodiments, when the exhaust baffle 3 is in the first position, the extending direction of the exhaust baffle 3 is inclined relative to the arrangement direction of the multiple exhaust inlets (in the unidirectional flow exhaust chamber 13, specifically, it is inclined relative to the direction from the closed end of the exhaust chamber 13 to the exhaust outlet 14). At this time, the exhaust baffle 3 is configured to guide the high-temperature substances and gases in the exhaust chamber 13 to flow towards the exhaust outlet 14, and the high-temperature substances and gases in the exhaust chamber 13 push against the exhaust baffle 3 to maintain the first position; for example, as shown in Figure 4, during the process of the high-temperature substances and gases flowing towards the front end, the high-temperature substances and gases will push against the second exhaust baffle to block the passage. Similarly, by sequentially pushing the channels of the third exhaust inlet, other exhaust baffles 3 block the channels of their corresponding exhaust inlets 15. This prevents high-temperature substances and gases from flowing to other exhaust ports, thus avoiding contact with the explosion-proof valves 201 of other battery cells 200 at the front end of the flow path. This protects the other battery cells 200 from the influence of high-temperature substances and gases. Finally, when the high-temperature substances and gases from the thermal runaway battery cell 200 are introduced into the exhaust assembly 100 through the corresponding exhaust inlet 15, they can only flow along a path that avoids other exhaust inlets 15 and are ejected from the exhaust outlet 14. Moreover, the inclined arrangement of the exhaust baffles 3 can better guide the high-temperature substances and gases to flow towards the exhaust outlet 14, making their flow smoother and faster. At this time, the exhaust baffles 3 have both a blocking function and a guiding function.

[0031] To better isolate the effects of high-temperature substances and gases on the normal battery cell 200, the opening of the venting component 2 is offset relative to the exhaust inlet 15. When the exhaust baffle 3 is in the first position, it isolates the corresponding exhaust inlet 15 from the flow path of the exhaust chamber 13, so that in the event of thermal runaway of a battery cell 200, high-temperature substances and gases will not flow above the explosion-proof valve 201 of the front-end normal battery cell 200. Specifically, the venting component 2 forms a semi-closed structure in the exhaust chamber 13. When the exhaust baffle 3 is in the first position to block the outlet of the venting component 2, the venting component 2 and the exhaust baffle 3 isolate an independent island area inside the exhaust chamber 13. The exhaust inlet 15 is located in this independent island area to form spatial isolation.

[0032] Referring to Figures 2 and 3, in this embodiment, the exhaust component 1 includes a base 11 and a cover plate 12. The base 11 and the cover plate 12 are made of high-temperature resistant insulating material, which is composed of silicon, boron and various metal oxides. The base 11 and the cover plate 12 are connected and form an exhaust chamber 13. An exhaust inlet 15 is provided on the bottom wall 111 of the base 11. An exhaust outlet 14 can be provided between the base 11 and the cover plate 12, or it can be provided on the base 11 or the cover plate 12. The air guide component 2 is fixed to the base 11 or the cover plate 12. When the base 11 and the cover plate 12 are connected, the base 11 and the cover plate 12 seal both sides of the air guide component 2, making the air guide component 2 a semi-closed structure. The exhaust baffle 3 is preferably pivotally connected between the base 11 and the cover plate 12 and is arranged corresponding to the outlet of the air guide component 2.

[0033] It should be noted that the base 11 and the cover plate 12 can be connected by using high-temperature resistant adhesive or by welding. No limitation is made on the connection method of the base 11 and the cover plate 12 here.

[0034] Referring to Figure 3, the air guide 2 is integrally connected to the bottom wall 111 of the base 11 and is arranged around the exhaust inlet 15. The cover plate 12 abuts against the air guide 2 for sealing. The first end of the air guide 2 is connected to one side wall of the base 11, and the second end of the air guide 2 has a gap with one side wall of the base 11 to form an opening. In this way, high-temperature substances and gases flow on one side of the air guide 2, which ensures that the exhaust baffle 3 will not be breached, thus affecting the normal operation of the battery cell 200.

[0035] Referring to Figures 4 and 5, multiple air guides 2 are arranged in a staggered manner. In two adjacent air guides 2, when one air guide 2 is connected to one side wall of the base 11, the other air guide 2 is connected to the other side wall of the base 11. Specifically, as shown in Figure 4, the first end of the first air guide is connected to the first side wall 112 of the base 11, and the second end of the first air guide has a gap with the first side wall 112 of the base 11 to form an opening. The first end of the second air guide is connected to the second side wall 113 of the base 11, and the second end of the second air guide has a gap with the second side wall 113 of the base 11 to form an opening. The third, fourth, ..., and M air guides are arranged in a staggered manner in this way. This arrangement facilitates the linear arrangement of multiple exhaust inlets 15 on the base 11, ensuring that the opening of each air guide 2 is not obstructed by adjacent air guides 2. The flow path of the exhaust chamber 13 is serpentine, improving the smoothness of the flow of high-temperature substances and gases within the exhaust chamber 13. A first guide surface 21 and a second guide surface 22 are provided at the connection between the first end of the air guide 2 and the side wall of the base 11. The first guide surface 21 and the second guide surface 22 are arranged opposite to each other. The first guide surface 21 is located on the outer side of the first end of the air guide 2, while the second guide surface 22 is located on the inner side of the first end of the air guide 2. The first guide surface 21 is configured to guide the flow of high-temperature substances and gases in the exhaust chamber 13.

[0036] Referring to Figures 3 and 4, in this embodiment, the first end of the exhaust baffle 3 is pivotally connected to the second end of the corresponding air guide 2. In the first position, the second end of the exhaust baffle 3 abuts against the side wall of the base 11 to block the opening of the air guide 2. In the second position, the second end of the exhaust baffle 3 abuts against the outer side of the adjacent air guide 2 to cut off the flow path of the exhaust chamber 13. Specifically, as shown in Figure 4, high-temperature substances and gases are introduced from the second exhaust inlet. When the first exhaust baffle is opened, the first exhaust baffle rotates upward and abuts against the outer side of the second air guide, thereby blocking the channel to the sealing end. As shown in Figure 5, high-temperature substances and gases are introduced from the first exhaust inlet. During the flow of the high-temperature substances and gases towards the exhaust outlet 14, the first exhaust baffle is pushed downward and rotates against the first side wall 112 of the base 11, thereby blocking the channel to the second exhaust inlet.

[0037] Referring to Figures 3 and 6, to facilitate the installation of the exhaust baffle 3, a rotating shaft 131 is provided at the first end of the exhaust baffle 3. The bottom wall 111 of the base 11 is provided with a first shaft hole 114 corresponding to the rotating shaft 131, and the cover plate 12 is provided with a second shaft hole 121 corresponding to the rotating shaft 131. The two ends of the rotating shaft 131 are respectively inserted into the first shaft hole 114 and the second shaft hole 121. In this way, when the base 11 and the cover plate 12 are connected, the exhaust baffle 3 can be clamped and the exhaust baffle can be rotated normally. The outer circumferential side of the rotating shaft 131 is in contact with the second end of the air guide 2. The fit clearance between the outer circumferential side of the rotating shaft 131 and the second end of the air guide 2 is preferably controlled at 0.2±0.1mm to ensure the sealing effect and not affect the rotation of the exhaust baffle.

[0038] It should be noted that the exhaust baffle 3 can also adopt an elastic deformation or one-time deformation structure, that is, when the battery cell 200 experiences thermal runaway, the corresponding exhaust baffle 3 can be blown open and deformed to the second position; or, the exhaust baffle 3 can also adopt other structures that can change between the first position and the second position, as long as the design requirements are met.

Claims

1. An exhaust assembly, applied to a battery module comprising multiple battery cells, comprising: An exhaust device is provided, wherein an exhaust chamber is formed within the exhaust device, and the exhaust device is further provided with at least one exhaust outlet hole communicating with the exhaust chamber and multiple exhaust inlets communicating with the exhaust chamber. The multiple exhaust inlets are arranged sequentially in the direction toward the exhaust outlet hole, and each exhaust inlet is configured to introduce high-temperature substances and gases discharged from the battery cell. Multiple air guides are provided in the exhaust chamber. At least some of the exhaust inlets are correspondingly provided with air guides. The air guides open in the direction of the exhaust outlet and connect the corresponding exhaust inlets to the exhaust chamber. Multiple exhaust baffles are provided, each exhaust baffle being movably disposed at an opening of the air guide member. Each exhaust baffle has a first position and a second position. When the exhaust baffle is in the first position, it blocks the corresponding opening of the air guide member. The high-temperature substances and gases flowing from the air guide to the exhaust chamber can drive the corresponding exhaust baffle to switch from the first position to the second position. When the exhaust baffle is in the second position, the exhaust baffle opens the opening of the corresponding air guide and cuts off the flow path of the exhaust chamber.

2. The exhaust assembly according to claim 1, wherein when the exhaust baffle is in the first position, the extending direction of the exhaust baffle is inclined relative to the arrangement direction of the plurality of exhaust inlets.

3. The exhaust assembly according to claim 1, wherein the opening of the air guide is eccentrically disposed relative to the exhaust inlet, and the exhaust baffle isolates the corresponding exhaust inlet from the flow path of the exhaust chamber when the exhaust baffle is in the first position.

4. The exhaust assembly according to any one of claims 1 to 3, wherein the exhaust component includes a base and a cover plate, the base and the cover plate are connected and form the exhaust chamber, the exhaust inlet is disposed on the bottom wall of the base, the air guide is integrally connected to the bottom wall of the base and disposed around the exhaust inlet, the cover plate abuts and seals against the air guide, the first end of the air guide is connected to a side wall of the base, and the second end of the air guide has a gap with a side wall of the base to form an opening.

5. The exhaust assembly according to claim 4, wherein a plurality of the air guides are arranged alternately in sequence, and in two adjacent air guides, when one of the air guides is connected to one of the side walls of the base, the other air guide is connected to the other side wall of the base.

6. The exhaust assembly according to claim 5, wherein the first end of the exhaust baffle is pivotally connected to the second end of the corresponding air guide member, and in the first position, the second end of the exhaust baffle abuts against the side wall of the base to block the opening of the air guide member, and in the second position, the second end of the exhaust baffle abuts against the outer side of the adjacent air guide member to cut off the flow path of the exhaust chamber.

7. The exhaust assembly according to claim 6, wherein the first end of the exhaust baffle is provided with a rotating shaft, the bottom wall of the base is provided with a first shaft hole corresponding to the rotating shaft, the cover plate is provided with a second shaft hole corresponding to the rotating shaft, the two ends of the rotating shaft are respectively inserted into the first shaft hole and the second shaft hole, and the outer circumferential side of the rotating shaft is in contact with the second end of the air guide.

8. The exhaust assembly according to claim 5, wherein the flow path of the exhaust chamber is serpentine.

9. The exhaust assembly according to claim 4, wherein a first guide surface and a second guide surface are provided at the connection between the first end of the air guide and the side wall of the base, and the first guide surface and the second guide surface are arranged opposite to each other.

10. The exhaust assembly according to claim 1, wherein the outer side of the exhaust component is further provided with a plurality of protrusions, each of the protrusions being provided with a corresponding exhaust inlet hole, and each of the protrusions being configured to fit against the outer periphery of the explosion-proof valve of the battery cell.

11. A battery module comprising a plurality of battery cells and an exhaust assembly as described in any one of claims 1 to 10, wherein the explosion-proof valve of each battery cell corresponds to an exhaust inlet of the exhaust assembly.

12. A battery pack having the battery module as described in claim 11.

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