Battery pack explosion-proof valve and battery pack

Abstract

The utility model provides a kind of battery pack explosion-proof valve and battery pack, it is related to battery technical field, including valve body, valve cover, elastic member, electromagnetic drive assembly and control unit, exhaust passage is equipped on valve body;Valve cover is movably arranged on valve body, for sealing or opening exhaust passage;Elastic member is used to provide the preload of valve cover to keep sealing exhaust passage;Electromagnetic drive assembly includes coil and magnetic member, magnetic member is fixedly connected with valve cover, coil keeps relative position fixed with valve body, coil is configured to generate magnetic force after being energized, drive magnetic member to drive the valve cover to move to coil direction against the preload of elastic member, to open exhaust passage and keep open state;Control unit is used to detect battery pack thermal runaway parameter, and drive signal is sent to coil in response to the parameter detected this. The explosion-proof valve can maintain the sustained unobstructed of exhaust passage during the whole pressure relief process, significantly improve the thermal runaway safety performance of battery pack.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery pack explosion-proof valve and a battery pack. Background Technology

[0002] With the rapid development of new energy technologies, battery packs, as core energy storage components, are widely used in electric vehicles, energy storage systems, and other electric devices. To ensure the safety of battery packs during use, explosion-proof valves are usually installed on their outer casings to release internal overpressure gases in a timely manner in the event of abnormal conditions such as thermal runaway, preventing the battery pack from exploding or being structurally damaged due to a sudden increase in pressure.

[0003] Currently, most explosion-proof valves commonly used in battery packs are spring valves, which generally include a guide rod, spring, piston, and vent hole on the valve body. The working principle of this type of explosion-proof valve is as follows: when the internal gas pressure of the battery pack rises to a set threshold due to thermal runaway or other reasons, the piston is subjected to gas pressure, overcoming the spring preload and causing displacement. This displacement drives the guide rod to move, opening the vent hole and allowing the high-temperature gas and medium to escape, thus achieving the pressure relief function.

[0004] However, such spring-based explosion-proof valves have significant shortcomings in practical use. Because the spring constantly applies a restoring force in the closing direction, during the depressurization process, as the internal pressure of the battery pack gradually decreases, the pressure acting on the piston correspondingly decreases. The spring then pushes the piston back, causing the exhaust channel gap to narrow or even close prematurely. This phenomenon interrupts the depressurization process, preventing the complete removal of residual high-temperature flammable gases from the battery pack, thus maintaining the risk of combustion or explosion and affecting the safety and reliability of the entire battery system. Utility Model Content

[0005] In view of this, this utility model proposes a battery pack explosion-proof valve and a battery pack to solve the problem that the pressure relief process of the existing spring valve structure is interrupted, resulting in high-pressure gas not being able to be completely discharged from the inside of the battery pack.

[0006] The technical solution of this utility model is implemented as follows: On the one hand, this utility model provides a battery pack explosion-proof valve, comprising: The valve body is used to install on the battery pack and has an exhaust passage. A valve cover is movably mounted on the valve body and is used to seal or open the exhaust passage; An elastic element, connecting the valve cover and the valve body, is used to provide a preload force to the valve cover to keep it sealed in the exhaust passage; An electromagnetic drive assembly includes a coil and a magnetic component. The magnetic component is fixedly connected to the valve cover, and the coil is fixed in a relative position to the valve body. The coil is configured to generate magnetic force after being energized, driving the magnetic component to move the valve cover against the preload of the elastic component toward the coil, thereby opening the exhaust passage and keeping it open. A control unit is used to detect battery pack thermal runaway parameters and send a drive signal to the coil in response to the detected parameters.

[0007] Based on the above technical solution, preferably, it also includes a housing, which is fixedly connected to the valve body, the coil is fixedly disposed inside the housing, and the housing is provided with several vent holes.

[0008] Based on the above technical solution, preferably, an installation bracket is provided inside the exhaust channel, and the elastic element is coaxially disposed between the valve body and the valve cover. One end of the elastic element is fixedly connected to the installation bracket, and the other end is fixedly connected to the valve cover.

[0009] Based on the above technical solution, preferably, the valve cover is a cylindrical structure with one end open, the elastic element is fixedly connected to the inner end face of the valve cover, the open end of the valve cover abuts against the end face of the valve body, and the magnetic element is coaxially fixed to the end of the valve cover away from the valve body.

[0010] Based on the above technical solution, preferably, the outer diameter of the valve cover is larger than the inner diameter of the exhaust channel, and the valve body end face is provided with a sealing element that connects to the opening end of the valve cover.

[0011] Based on the above technical solution, preferably, the outer wall of the valve cover is provided with a guide portion along its axial direction, and the end face of the valve body has a guide rail that cooperates with the guide portion.

[0012] Based on the above technical solution, preferably, a filter screen is provided on the exhaust channel.

[0013] Based on the above technical solution, preferably, the control unit includes a detection module and a controller. The detection module is used to detect the thermal runaway parameters of the battery pack. The signal output terminal of the detection module is electrically connected to the signal input terminal of the controller. The control output terminal of the controller is electrically connected to the coil and is used to respond to the thermal runaway parameters and send a drive signal to the coil.

[0014] Based on the above technical solution, preferably, the sensor control unit is fixedly installed inside the housing.

[0015] Secondly, this utility model proposes a battery pack, including a housing and a battery pack explosion-proof valve as described in the first aspect, which is disposed in the housing. The housing has an installation hole, and the valve body is fixedly disposed in the installation hole.

[0016] The present invention has the following advantages over the prior art: (1) The battery pack explosion-proof valve disclosed in this utility model achieves rapid response and opening of the explosion-proof valve in the early stage of thermal runaway by actively detecting thermal runaway parameters and triggering signals by the control unit, combined with a highly reliable opening mechanism driven by electromagnetic force. It also maintains the continuous unobstructed exhaust channel throughout the entire depressurization process, and finally completely solves the technical problem of traditional explosion-proof valves closing prematurely due to reliance on gas pressure changes, resulting in depressurization interruption, and significantly improves the thermal runaway safety performance of the battery pack.

[0017] (2) By providing a guide portion along the axial direction on the outer wall of the valve cover, and providing a guide rail that cooperates with the guide portion on the end face of the valve body, the valve cover can move coaxially relative to the valve body when it moves relative to the valve body through the cooperation of the guide portion and the guide rail, thereby improving the reliability of the entire explosion-proof valve pressure relief opening and sealing process. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a first-view exploded view of the battery pack explosion-proof valve disclosed in this utility model. Figure 2 This is a second-view exploded view of the battery pack explosion-proof valve disclosed in this utility model. Figure 3 This is a three-dimensional structural diagram of the battery pack explosion-proof valve disclosed in this utility model; Figure 4 This is a schematic diagram of the planar structure of the battery pack explosion-proof valve disclosed in this utility model; Figure 5 for Figure 4 Planar sectional view at point AA; Figure 6 This is a schematic diagram of the assembly structure of the battery pack housing and the battery pack explosion-proof valve disclosed in this utility model. Figure label: 1. Valve body; 11. Exhaust passage; 12. Mounting bracket; 13. Guide rail; 14. Filter screen; 2. Valve cover; 21. Guide part; 3. Elastic element; 4. Electromagnetic drive assembly; 41. Coil; 42. Magnetic element; 5. Control unit; 6. Housing; 61. Vent hole; M. Seal; 7. Housing; 71. Mounting hole. Detailed Implementation

[0020] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0021] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0022] In the description of the embodiments of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model based on the specific circumstances.

[0023] In the description of the embodiments of this utility model, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this utility model.

[0024] Furthermore, 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0025] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0026] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the applicability of other processes and / or the use of other materials.

[0027] like Figure 1 As shown, combined with Figure 2-5 This utility model discloses a battery pack explosion-proof valve, which includes a valve body 1, a valve cover 2, an elastic element 3, an electromagnetic drive assembly 4, and a control unit 5.

[0028] The valve body 1 forms the basic structure of the explosion-proof valve. It is equipped with an exhaust channel 11, which provides a path for the discharge of high-temperature and high-pressure gas. At the same time, the valve body 1 serves as a mounting base to fix the entire explosion-proof valve to the battery pack, ensuring communication with the internal space of the battery pack.

[0029] The valve cover 2 is movably mounted on the valve body 1. Its core function is to seal or open the exhaust passage 11, maintaining the airtightness of the battery pack under normal conditions and providing an opening for gas release under abnormal conditions.

[0030] The elastic element 3 is connected between the valve cover 2 and the valve body 1. It provides a continuous preload force to keep the valve cover 2 sealed to the exhaust passage 11 under normal conditions. This design ensures the sealing requirements of the battery pack under normal operating conditions and prevents unnecessary media leakage.

[0031] The electromagnetic drive assembly 4 consists of a coil 41 and a magnetic component 42. The magnetic component 42 is fixedly connected to the valve cover 2 and can be a permanent magnet. The coil 41 is fixed in a relative position to the valve body 1. The characteristic of this assembly is that the coil 41 can generate magnetic force when energized. This magnetic force acts on the magnetic component 42 and drives the valve cover 2 to move as a whole. This displacement directly overcomes the preload force of the elastic component 3, thereby realizing the opening of the exhaust channel 11. After opening, it can remain in a normally open state to ensure that the high temperature and high pressure gas inside the battery pack can be completely released through the exhaust channel 11.

[0032] The control unit 5, acting as the triggering mechanism for the entire system, is responsible for detecting and responding to the thermal runaway parameters of the battery pack. By detecting changes in the internal state of the battery pack, it automatically sends a drive signal to the coil 41 when an anomaly is detected, thereby activating the electromagnetic drive component 4. This design means that the opening of the explosion-proof valve no longer depends on changes in internal pressure, but responds by detecting direct parameters of thermal runaway, fundamentally changing the working mechanism of traditional explosion-proof valves.

[0033] The battery pack explosion-proof valve disclosed in this utility model achieves rapid response and opening of the explosion-proof valve in the early stage of thermal runaway by actively detecting and signal triggering thermal runaway parameters through the control unit 5, combined with a highly reliable opening mechanism driven by electromagnetic force. It also maintains the continuous unobstructed flow of the exhaust channel 11 throughout the entire depressurization process, thus completely solving the technical problem of traditional explosion-proof valves closing prematurely due to reliance on air pressure changes, which leads to depressurization interruption. This significantly improves the thermal runaway safety performance of the battery pack.

[0034] As one implementation, the control unit 5 includes a detection module and a controller. The detection module is used to detect battery pack thermal runaway parameters. Specifically, the detection module includes one or more of a temperature sensor, a smoke sensor, and a pressure sensor to detect temperature, smoke, and gas pressure. These parameters are important parameters affecting battery pack thermal runaway.

[0035] The signal output terminal of the detection module is electrically connected to the signal input terminal of the controller, and the control output terminal of the controller is electrically connected to the coil 41, used to respond to thermal runaway parameters and send a drive signal to the coil 41. The controller receives thermal runaway parameters in real time. When the thermal runaway parameters reach the preset threshold of the controller, the controller will send a drive signal to the coil 41, thereby energizing the coil 41.

[0036] In this embodiment, the controller can be an STM32G031K8T6 microcontroller from STMicroelectronics. This chip connects to the signal output of the detection module via its GPIO pins to acquire sensor data; simultaneously, it connects to the gate of a switching MOSFET via another GPIO pin, with the source and drain of the MOSFET connected in series in the coil's power supply circuit. When the microcontroller determines, based on its internal hardware comparator, that the input signal exceeds a preset level, its output pin will output a high-level signal to turn on the MOSFET, thereby controlling the power supply to the coil. The entire control logic is implemented through hardware circuitry and does not rely on software program execution.

[0037] To maintain the relative position of the coil 41 and the valve body 1, and to ensure that the valve body 1, valve cover 2, elastic element 3, and electromagnetic drive assembly 4 form an independent module, the battery pack explosion-proof valve in this embodiment also includes a housing 6. The housing 6 and the valve body 1 are fixedly connected. Specifically, the housing 6 and the valve body 1 can be connected by threads, bolts, or snap-fit ​​connections. An installation space is formed between the housing 6 and the valve body 1, thereby accommodating the valve cover 2, elastic element 3, and electromagnetic drive assembly 4 within the installation space. The coil 41 is fixedly disposed inside the housing 6. Thus, the coil 41 maintains its relative position with the valve body 1 with the help of the housing 6. When the coil 41 is energized, it generates a magnetic force that attracts the magnetic element 42, driving the valve cover 2 to move away from the valve body 1, disengaging the valve cover 2 from the valve body 1, and ensuring that gas can be discharged from inside the battery pack through the exhaust channel 11 to the outside of the explosion-proof valve.

[0038] Since the outer casing 6 is open at one end, after it is fixedly connected to the valve body 1, the gas inside the battery pack cannot enter the installation space formed by the outer casing 6 and the valve body 1. Therefore, in this embodiment, a number of vent holes 61 are provided on the outer casing 6. Thus, the high-pressure and high-temperature gas inside the battery pack enters the installation space through the vent holes 61. When the exhaust channel 11 is opened, the high-pressure and high-temperature gas can be discharged in time.

[0039] In this embodiment, a through hole is provided at the center of the surface of the valve body 1, which constitutes an exhaust channel 11. In order to achieve coaxial connection between the elastic element 3, the valve body 1, and the valve cover 2, an installation bracket 12 is provided inside the exhaust channel 11. The installation bracket 12 is composed of multiple reinforcing ribs, which are evenly fixed inside the exhaust channel 11. One end of the multiple reinforcing ribs is fixedly connected to the valve body 1, and the end of the multiple reinforcing ribs facing the exhaust channel 11 is fixedly connected, thereby providing a mounting base for the elastic element 3.

[0040] In the actual assembly process, one end of the elastic element 3 is fixedly connected to the center of the mounting bracket 12, and the other end is fixedly connected to the valve cover 2. Through the pre-tightening force of the elastic element 3, the valve cover 2 is pulled towards the valve body 1, thereby realizing the contact between the valve cover 2 and the valve body 1 and sealing the exhaust passage 11.

[0041] In some implementations, the valve cover 2 is a cylindrical structure with one end open, the elastic element 3 is fixedly connected to the inner end face of the valve cover 2, and the open end of the valve cover 2 abuts against the end face of the valve body 1.

[0042] By setting the valve cover 2 as a cylindrical structure, it is convenient to accommodate the elastic element 3 inside the accommodating space formed by the valve cover 2 and the valve body 1. The open end of the valve cover 2 covers the outside of the exhaust passage 11, and the exhaust passage 11 is blocked by the abutment between the open end of the valve cover 2 and the end face of the valve body 1.

[0043] The magnetic component 42 is coaxially fixed to the end of the valve cover 2 away from the valve body 1. This allows the valve cover 2 to move coaxially relative to the valve body 1 when pulled by magnetic force. This avoids the problem that the direction of force on the elastic component 3 is not coaxial with the direction of magnetic pull, which would prevent the valve cover 2 from effectively sealing with the valve body 1 after the gas is depressurized, resulting in a misalignment of the seal.

[0044] In this embodiment, the outer diameter of the valve cover 2 is larger than the inner diameter of the exhaust channel 11. Therefore, the open end of the valve cover 2 covers the outside of the exhaust channel 11, and a sealing element M connected to the open end of the valve cover 2 is provided on the end face of the valve body 1. When no pressure relief operation is performed, under the pre-tightening force of the elastic element 3, the valve cover 2 is pulled by the elastic element 3, causing the open end of the valve cover 2 and the sealing element M on the end face of the valve body 1 to be squeezed, achieving a reliable sealing fit and preventing external media from entering the battery pack through the connection between the valve body 1 and the valve cover 2.

[0045] Since the valve cover 2 is connected to the valve body 1 through the elastic element 3, although the elastic element 3, the valve cover 2 and the valve body 1 are coaxial, after the valve cover 2 is depressurized and the coil 41 is de-energized, the elastic element 3 will instantly reset the valve cover 2 due to the pre-tightening force. However, since the elastic element 3 is a flexible element, the valve cover 2 and the valve body 1 will not be coaxial at the moment of reset, which will lead to the problem of poor sealing between the valve cover 2 and the valve body 1 to a certain extent.

[0046] Therefore, in this embodiment, a guide portion 21 is provided on the outer wall of the valve cover 2 along its axial direction, and the end face of the valve body 1 has a guide rail 13 that cooperates with the guide portion 21. With this configuration, when the valve cover 2 moves relative to the valve body 1, the guide portion 21 and the guide rail 13 can cooperate to keep the valve cover 2 moving coaxially relative to the valve body 1, thereby improving the reliability of the entire explosion-proof valve pressure relief opening and sealing process.

[0047] As one implementation, a filter screen 14 is provided on the exhaust passage 11. This filter screen 14 can prevent large external particles from entering the explosion-proof valve, especially to prevent these large particles from falling into the connection between the valve body 1 and the valve cover 2, which would cause poor sealing between the valve cover 2 and the valve body 1, thereby improving the sealing reliability of the battery pack.

[0048] As one implementation, the control unit 5 is fixedly installed inside the housing 6, thereby enabling multiple components to be assembled to form a complete battery pack explosion-proof valve, making the battery pack explosion-proof valve an independent module, which facilitates direct assembly operations during battery pack production.

[0049] This embodiment also discloses a battery pack, as shown in the attached drawing. Figure 6 As shown, the device includes a housing 7 and a battery pack explosion-proof valve installed inside the housing 7. The housing 7 has a mounting hole 71, and the valve body 1 is fixed to the mounting hole 71. Other components of the battery pack explosion-proof valve are located inside the housing 7. The control unit 5 inside the battery pack explosion-proof valve monitors the thermal runaway parameters inside the housing 7 in real time. When the thermal runaway trigger condition is reached, the electromagnetic drive component 4 is activated, thereby quickly opening the exhaust channel 11. When the electromagnetic force is maintained, the exhaust channel 11 can be kept open, thereby fully releasing the high-pressure gas inside the battery pack and improving the safety performance of the battery pack.

[0050] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A battery pack explosion-proof valve, characterized in that, include: A valve body (1) is used to be installed on a battery pack, and an exhaust channel (11) is provided on the valve body (1); A valve cover (2) is movably disposed on the valve body (1) for sealing or opening the exhaust passage (11); The elastic element (3) connects the valve cover (2) and the valve body (1) and provides a preload force to the valve cover (2) to keep it sealed in the exhaust passage (11); The electromagnetic drive assembly (4) includes a coil (41) and a magnetic element (42). The magnetic element (42) is fixedly connected to the valve cover (2). The coil (41) is fixed in a relative position to the valve body (1). The coil (41) is configured to generate magnetic force after being energized, driving the magnetic element (42) to move the valve cover (2) against the preload of the elastic element (3) toward the coil (41) to open the exhaust passage (11). The control unit (5) is used to detect the thermal runaway parameters of the battery pack and send a drive signal to the coil (41) in response to the detected parameters.

2. The battery pack explosion-proof valve as described in claim 1, characterized in that: It also includes a housing (6), which is fixedly connected to the valve body (1), and the coil (41) is fixedly disposed inside the housing (6). The housing (6) is provided with several vent holes (61).

3. The battery pack explosion-proof valve as described in claim 1, characterized in that: An installation bracket (12) is provided inside the exhaust channel (11). The elastic element (3) is coaxially disposed between the valve body (1) and the valve cover (2). One end of the elastic element (3) is fixedly connected to the installation bracket (12), and the other end is fixedly connected to the valve cover (2).

4. The battery pack explosion-proof valve as described in claim 3, characterized in that: The valve cover (2) is a cylindrical structure with one end open. The elastic element (3) is fixedly connected to the inner end face of the valve cover (2). The open end of the valve cover (2) abuts against the end face of the valve body (1). The magnetic element (42) is coaxially fixed to the end of the valve cover (2) away from the valve body (1).

5. The battery pack explosion-proof valve as described in claim 4, characterized in that: The outer diameter of the valve cover (2) is larger than the inner diameter of the exhaust channel (11), and the valve body (1) end face is provided with a sealing element (M) that is connected to the opening end of the valve cover (2).

6. The battery pack explosion-proof valve as described in claim 4, characterized in that: The outer wall of the valve cover (2) is provided with a guide portion (21) along its axial direction, and the end face of the valve body (1) has a guide rail (13) that cooperates with the guide portion (21).

7. The battery pack explosion-proof valve as described in claim 3, characterized in that: A filter screen (14) is provided on the exhaust channel (11).

8. The battery pack explosion-proof valve as described in claim 1, characterized in that: The control unit (5) includes a detection module and a controller. The detection module is used to detect the thermal runaway parameters of the battery pack. The signal output terminal of the detection module is electrically connected to the signal input terminal of the controller. The control output terminal of the controller is electrically connected to the coil (41) to respond to the thermal runaway parameters and send a drive signal to the coil (41).

9. The battery pack explosion-proof valve as described in claim 2, characterized in that: The control unit (5) is fixedly installed inside the housing (6).

10. A battery pack, comprising a housing (7), characterized in that, It also includes a battery pack explosion-proof valve as described in any one of claims 1 to 9, which is disposed in the housing (7), wherein the housing (7) has an installation hole (71) and the valve body (1) is fixedly disposed in the installation hole (71).

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