Explosion-proof valve, battery and gas pressure control method

Abstract

The invention relates to the technical field of battery safety, in particular to an anti-explosion valve, a battery and a gas pressure control method.The anti-explosion valve comprises a valve body, a sealing assembly and a switching assembly, and the valve body is provided with an anti-explosion channel. At least one part of the sealing assembly is located in the anti-explosion channel and can move in the extending direction of the anti-explosion channel. The switching assembly is connected with the sealing assembly, and the switching assembly is configured to be capable of driving the sealing assembly according to the gas pressure value of the inlet of the anti-explosion channel so that the sealing assembly can seal or unseal the anti-explosion channel. The safety of the battery can be improved.

Description

Technical Field

[0001] The present application relates to the field of battery safety technology, and in particular to an explosion-proof valve, a battery, and a gas pressure control method. Background Art

[0002] A battery is a component used to provide functions for other components, generally generating electrical energy through an internal chemical reaction, and supplying these components.

[0003] A battery generally includes a containing cavity, an electrolyte and an electrode. The electrolyte generates electrical energy by interacting with the electrode.

[0004] In the related art, the electrolyte will generate gas when the battery is working. The gas heats up in the closed containing cavity, which is prone to thermal runaway, so the safety is relatively low. Summary of the invention

[0005] In view of this, the present application provides an explosion-proof valve, a battery, and a gas pressure control method to improve their safety.

[0006] Specifically, the following technical solutions are included:

[0007] A first aspect of the present application provides an explosion-proof valve, the explosion-proof valve comprising a valve body, a sealing assembly and a switching assembly, wherein:

[0008] The valve body has an explosion-proof passage.

[0009] At least a portion of the sealing assembly is located in the explosion-proof passage and is movable along an extension direction of the explosion-proof passage.

[0010] The switching component is connected to the sealing component, and the switching component is configured to drive the sealing component according to the gas pressure value at the inlet of the explosion-proof channel, so that the sealing component can seal or unseal the explosion-proof channel.

[0011] Optionally, the sealing assembly includes a push rod having a sealing surface at one end, the orthographic projection of the outlet of the explosion-proof channel on the projection plane is located within the orthographic projection of the sealing surface on the projection plane, and the projection plane is a plane perpendicular to the extension direction of the explosion-proof channel.

[0012] Optionally, the sealing assembly includes a sealing portion, the sealing portion is located on a side of the sealing surface facing the explosion-proof passage, the sealing portion surrounds the push rod and is annular, and the sealing portion is used to abut against the valve body.

[0013] Optionally, the switching assembly further comprises a spring, wherein the spring is connected to the sealing surface so as to apply a restoring force to the sealing surface to return to the explosion-proof passage when the sealing surface unseals the explosion-proof passage.

[0014] Optionally, the switching component includes a coil, and the coil and the sealing component are arranged in sequence along the extension direction of the explosion-proof channel, and the coil is used to apply a magnetic force to the sealing component to unseal the explosion-proof channel.

[0015] Optionally, the sealing assembly has an iron core at one end facing the coil.

[0016] Optionally, the switching component includes a pressure sensor and a control module, the control module is electrically connected to the pressure sensor and the coil, and the pressure sensor is used to monitor the gas pressure value at the entrance of the explosion-proof channel.

[0017] A second aspect of the present application provides a battery, comprising a housing and an explosion-proof valve as described in the above technical solution, wherein the housing has a containing cavity, and an entrance of the explosion-proof passage is connected to the containing cavity.

[0018] A third aspect of the present application provides a gas pressure control method, wherein the gas pressure control method uses the battery described in the above technical solution, comprising:

[0019] Obtaining a gas pressure value of the containing chamber;

[0020] The magnitude relationship between the gas pressure value and the set value is determined, and according to the magnitude relationship, the switching component is controlled to drive the sealing component to seal or unseal the explosion-proof passage.

[0021] Optionally, the determining the magnitude relationship between the gas pressure value and a set value, and controlling the switching component to drive the sealing component to seal or unseal the explosion-proof passage according to the magnitude relationship, specifically includes:

[0022] If the gas pressure value is greater than or equal to the first set value and less than the second set value, and the temperature change of the accommodating chamber reaches the third set value and the voltage of the battery reaches the fourth set value, the switching component is controlled to drive the sealing component to unseal the explosion-proof channel until the gas pressure value is less than the first set value and lasts for a first set time;

[0023] If the gas pressure value is greater than the second set value, the switching component is controlled to drive the sealing component to unseal the explosion-proof passage until the gas pressure value is less than the first set value and lasts for a first set time.

[0024] The beneficial effects of the technical solution provided by the embodiment of the present application include at least: the explosion-proof channel of the valve body can allow gas to enter from the inlet and leave from the outlet to reduce the gas pressure at the inlet. The sealing component that can move along the extension direction of the explosion-proof channel can cooperate with the explosion-proof channel to achieve the sealing and unsealing of the explosion-proof channel. The switching component uses the sealing component to unseal and seal the explosion-proof channel according to the gas pressure value at the inlet of the explosion-proof channel, which is conducive to improving the adaptability of the explosion-proof valve to the working conditions inside the battery, thereby reducing the occurrence of thermal runaway of the battery and improving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 A schematic diagram of the structure of an explosion-proof valve provided in an embodiment of the present application;

[0027] Figure 2 A schematic flow chart of a pressure control method provided in an embodiment of the present application;

[0028] Figure 3 A schematic diagram of a flow chart of a method for determining a size relationship provided in an embodiment of the present application;

[0029] Figure 4 A schematic diagram of an automobile workflow provided by an embodiment of the present application;

[0030] Figure 5 A schematic diagram of the operation of an electrical component of an automobile provided in an embodiment of the present application.

[0031] The reference numerals in the figures represent respectively:

[0032] 1. Valve body; 100. Explosion-proof passage;

[0033] 2. Sealing assembly; 21. Push rod; 211. Sealing surface; 22. Sealing part; 23. Iron core;

[0034] 3. Switching assembly; 31. Spring; 32. Coil.

[0035] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0037] The directional nouns involved in the embodiments of the present application, such as "upper", "lower", "side", etc., are generally represented by Figure 1 The relative relationship of the orientation shown in the figure is used as the basis, and these orientation terms are used only to more clearly describe the relationship between structures, not to describe absolute orientation. When the product is placed in different postures, the orientation may change, for example, "up" and "down" may be interchangeable.

[0038] Unless otherwise defined, all technical terms used in the embodiments of the present application have the same meanings as commonly understood by those of ordinary skill in the art.

[0039] In order to make the technical solutions and advantages of the present application more clear, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0040] The first aspect of the present application provides an explosion-proof valve, such as Figure 1 As shown, the explosion-proof valve includes a valve body 1, a sealing component 2 and a switching component 3, wherein:

[0041] The valve body 1 has an explosion-proof passage 100 .

[0042] At least a portion of the sealing assembly 2 is located in the explosion-proof passage 100 and is movable along the extension direction of the explosion-proof passage 100 .

[0043] The switching component 3 is connected to the sealing component 2 , and the switching component 3 is configured to drive the sealing component 2 according to the gas pressure value at the inlet of the explosion-proof passage 100 , so that the sealing component 2 seals or unseals the explosion-proof passage 100 .

[0044] It is understandable that the explosion-proof channel 100 of the valve body 1 can allow gas to enter from the inlet and leave from the outlet to reduce the gas pressure at the inlet. The sealing component 2 that can move along the extension direction of the explosion-proof channel 100 can cooperate with the explosion-proof channel 100 to achieve the sealing and unsealing of the explosion-proof channel 100. The switching component 3 uses the sealing component 2 to unseal and seal the explosion-proof channel 100 according to the gas pressure value at the inlet of the explosion-proof channel 100, which is conducive to improving the adaptability of the explosion-proof valve to the working conditions inside the battery, thereby reducing the occurrence of thermal runaway of the battery and improving safety.

[0045] In an embodiment of the present application, the switching component 3 can periodically monitor the gas pressure value at the entrance of the explosion-proof channel 100. Every time a gas pressure value is obtained, the sealing component 2 is driven according to its size, so that the sealing component 2 is in a state of sealing the explosion-proof channel 100 or unsealing the explosion-proof channel 100.

[0046] In the embodiment of the present application, when the gas pressure value is greater than a preset value, the sealing component 2 can seal the explosion-proof channel 100, etc., and when the gas pressure value is less than the preset value, the sealing component 2 can unseal the explosion-proof channel 100.

[0047] In the embodiment of the present application, the sealing component 2 can seal and unseal the explosion-proof passage 100 by changing the amount of the portion extending into the explosion-proof passage 100 .

[0048] In the embodiment of the present application, the sealing assembly 2 can seal the explosion-proof passage 100 by sealing the exit, the entrance or other internal positions of the explosion-proof passage 100 .

[0049] In the embodiment of the present application, when the gas in the explosion-proof passage 100 can enter from the inlet and leave from the outlet, it can be considered that the sealing assembly 2 unseals the explosion-proof passage 100.

[0050] In some of the embodiments of this application, Figure 1 As shown, the sealing assembly 2 includes a push rod 21, one end of which has a sealing surface 211, the orthographic projection of the outlet of the explosion-proof passage 100 on the projection plane is located within the orthographic projection of the sealing surface 211 on the projection plane, and the projection plane is a plane perpendicular to the extension direction of the explosion-proof passage 100.

[0051] It can be understood that the orthographic projection of the outlet of the explosion-proof channel 100 on the projection plane is located within the orthographic projection of the sealing surface 211 on the projection plane, so that when the sealing surface 211 covers the outlet, the explosion-proof channel 100 can be sealed, which is beneficial for the electrolyte in the battery to react and generate electricity; when the sealing surface 211 is separated from the outlet, the explosion-proof channel 100 can be unsealed, which is beneficial for excess gas at the entrance to leave through the explosion-proof channel 100, thereby reducing the gas pressure value at the entrance.

[0052] In some of the embodiments of this application, Figure 1 As shown, the sealing assembly 2 includes a sealing portion 22 , which is located on the side of the sealing surface 211 facing the explosion-proof passage 100 , and the sealing portion 22 surrounds the push rod 21 to be annular, and is used to abut against the valve body 1 .

[0053] It can be understood that the sealing portion 22 can fill the gap between the sealing surface 211 and the circumferential position of the entrance of the explosion-proof channel 100 on the valve body 1 by deformation. After filling, the gas will be interfered when leaving the explosion-proof channel 100 from the outlet of the explosion-proof channel 100, which is beneficial to improve the sealing performance of the sealing surface 211 to the explosion-proof channel 100.

[0054] In the embodiment of the present application, the sealing portion 22 may be a sealing ring.

[0055] In some of the embodiments of this application, Figure 1 As shown, the switching assembly 3 further includes a spring 31 , which is connected to the sealing surface 211 so as to apply a restoring force to the sealing surface 211 to return to the explosion-proof passage 100 when the sealing surface 211 unseals the explosion-proof passage 100 .

[0056] It is understandable that the spring 31 can maintain the position stability of the sealing component 2 and guide the sealing component 2, which is conducive to the axial movement of the sealing component 2 along the spring 31 to achieve the sealing and unsealing of the explosion-proof passage 100. The spring 31 is also conducive to the sealing component 2 maintaining the sealing state of the explosion-proof passage 100. At the same time, after the switching component 3 drives the sealing component 2 to unseal the explosion-proof passage 100, the reset force generated by the spring 31 can be used to keep the sealing state of the explosion-proof passage 100.

[0057] In addition, when the switching component 3 utilizes other signals, such as electrical signals, to drive the sealing component 2, due to the hysteresis of this type of control method, if the pressure at the inlet position rises too quickly, it may easily cause the explosion-proof valve to fail. Therefore, the spring 31 can react quickly when the above situation occurs, so that the sealing component 2 can unseal the explosion-proof channel 100 to allow gas to be discharged.

[0058] In some of the embodiments of this application, Figure 1 As shown, the switching component 3 includes a coil 32 , and the coil 32 and the sealing component 2 are sequentially arranged along the extension direction of the explosion-proof passage 100 . The coil 32 is used to apply a magnetic force to the sealing component 2 to unseal the explosion-proof passage 100 .

[0059] It can be understood that when the gas pressure value at the entrance of the explosion-proof channel 100 is greater than the set value, the coil 32 can generate magnetic force, which drives the sealing component 2 to unseal the explosion-proof channel 100, thereby improving the adaptability of the explosion-proof valve to the working conditions inside the battery, thereby reducing the thermal runaway of the battery.

[0060] In the embodiment of the present application, the coil 32 is magnetized when energized, and the magnetized coil 32 generates a magnetic force on the sealing component 2, so that the sealing component 2 can overcome the elastic force from the spring 31 and move toward the exit of the explosion-proof channel 100, thereby unsealing the explosion-proof channel 100; when the coil 32 is de-energized, the magnetic force disappears, and the spring 31 recovers elastically, pulling the sealing component 2 back toward the entrance of the explosion-proof channel 100, thereby sealing the explosion-proof channel 100.

[0061] In the embodiment of the present application, the coil 32 can be located in the explosion-proof channel 100 to drive the sealing component 2, or it can be located in the valve body 1 and separated from the explosion-proof channel 100, and drive the sealing component 2. The coil 32 can also be located outside the valve body 1 and drive the sealing component 2.

[0062] In some of the embodiments of this application, Figure 1 As shown, the sealing assembly 2 has an iron core 23 at one end facing the coil 32 .

[0063] It can be understood that the iron core 23 is conducive to the repulsion and attraction of the magnetic force of the coil 32, so as to achieve the driving effect on the sealing component 2, and the sealing component 2 can achieve the sealing and unsealing of the explosion-proof channel 100.

[0064] In some embodiments of the present application, the switching component 3 includes a pressure sensor and a control module. The control module is electrically connected to the pressure sensor and the coil 32 . The pressure sensor is used to monitor the gas pressure value at the entrance of the explosion-proof channel 100 .

[0065] It is understandable that the gas pressure value obtained by the pressure sensor can be used by the control module to determine the gas pressure at the entrance of the explosion-proof channel 100, and drive the sealing component 2 according to the actual situation to achieve unsealing and sealing of the explosion-proof channel 100.

[0066] A second aspect of the present application provides a battery, which includes a housing and an explosion-proof valve as described in the above technical solution, wherein the housing has a receiving cavity, and an entrance of the explosion-proof passage 100 is connected to the receiving cavity.

[0067] It can be understood that, due to the use of the explosion-proof valve of the above embodiment, the battery of the present application has the same technical effects as the above embodiment, which will not be described in detail here.

[0068] In the embodiment of the present application, the switching component 3 includes a pressure sensor and a BMS (battery management system), the BMS is electrically connected to the pressure sensor and the coil 32, and the pressure sensor is used to monitor the gas pressure value at the entrance of the explosion-proof passage 100. The switching component 3 includes a coil 32, and the coil 32 and the sealing component 2 are sequentially arranged along the extension direction of the explosion-proof passage 100, and the coil 32 is used to apply a magnetic force to the sealing component 2 to unseal the explosion-proof passage 100. The switching component 3 also includes a spring 31, and the spring 31 is connected to the sealing surface 211 to apply a reset force to the sealing surface 211 to return to the explosion-proof passage 100 when the sealing surface 211 unseals the explosion-proof passage 100.

[0069] In the embodiment of the present application, the pressure sensor periodically wakes itself up and continuously monitors the pressure change in the accommodation chamber. Under normal circumstances, the pressure in the accommodation chamber is 1 standard atmospheric pressure, which is about 101KPa. After thermal runaway occurs, a large amount of gas is instantly generated in the accommodation chamber, and the gas pressure rises sharply. At this time, the pressure sensor detects that the pressure exceeds the set threshold, and will send a wake-up signal to the BMS to wake up the BMS. After the BMS is awakened by the pressure sensor, it sends a request signal to the pressure sensor, establishes a communication connection with the pressure sensor, and reads the gas pressure value. After the detected gas pressure value exceeds the threshold set by the BMS, the BMS determines that the battery pack has indeed thermal runaway according to the detected voltage or temperature change. Then, it outputs a low-level signal through the control hardware circuit. The low-level signal is connected to one end of the coil 32, and the other end of the coil 32 is externally connected to the 12V DC power supply system. The explosion-proof valve coil 32 is energized to generate electromagnetic suction, forcing the electronic explosion-proof valve to be fully opened, and the gas in the accommodation chamber is discharged to reduce the pressure of the battery.

[0070] When the battery is in normal condition, the pressure sensor will automatically wake up at regular intervals to check the gas pressure in the battery pack. When the gas pressure is normal, the BMS will not wake up. At this time, the BMS does not pass current to the coil 32, and does not generate a magnetic field and thus a magnetic force. Therefore, under the tension of the spring 31, the explosion-proof valve is in a completely closed state, isolating the accommodating cavity from the outside world.

[0071] Once thermal runaway occurs, the pressure sensor detects abnormal pressure and wakes up the BMS. The BMS immediately reads the gas pressure value to continuously monitor the pressure value in the bag. After the pressure value exceeds the first alarm threshold, the voltage and temperature values ​​are detected to reach the alarm threshold, or the pressure value is directly detected to exceed the second alarm threshold, the electronic explosion-proof valve is controlled to open and discharge the gas, and a thermal runaway alarm fault is issued to the BMS. The vehicle also issues an audible and visual alarm to remind passengers to stay away from the vehicle immediately. Among them, the first alarm threshold ranges from 104 to 110KPa, and the second alarm threshold ranges from greater than 110KPa.

[0072] If the pressure inside the battery pack continues to decrease after the explosion-proof valve is opened, and the pressure value is lower than the alarm threshold set by the BMS, if the battery pack pressure does not rise again within 1 minute, the BMS automatically enters a dormant state and disconnects the power supply of the electronic explosion-proof valve, so that the electronic explosion-proof valve closes naturally under the tension of its own spring 31 to maintain isolation between the inside and outside of the battery pack.

[0073] Taking into account the impact of the system's false alarm of valve opening, the alarm threshold of the pressure sensor can be divided into two levels. Level 1 is when the gas pressure value is ≥104KPa. At this time, the pressure sensor wakes up the BMS, and the BMS detects whether the voltage and temperature values ​​reach the alarm threshold. If both conditions are met, it is determined that the battery has thermal runaway, and the drive coil 32 is used to unseal the explosion-proof channel 100; Level 2 is when the gas pressure value is greater than 110KPa. At this time, it is determined that the battery has thermal runaway, and the drive coil 32 is used to unseal the explosion-proof channel 100, and a thermal runaway fault is reported at the same time.

[0074] The third aspect of the present application provides a gas pressure control method, such as Figure 2 As shown, the gas pressure control method applies the battery of the above technical solution, including:

[0075] Obtaining the gas pressure value of the containing chamber;

[0076] The magnitude relationship between the gas pressure value and the set value is determined, and the switching component 3 is controlled to drive the sealing component 2 to seal or unseal the explosion-proof passage 100 according to the magnitude relationship.

[0077] It is understandable that the gas pressure value can represent the pressure situation in the accommodation chamber. Generally, the larger the gas pressure value, the greater the gas pressure in the accommodation chamber. By judging the relationship between the gas pressure value and the set value, it can be used to judge whether there is a risk of thermal runaway in the accommodation chamber. This is conducive to the sealing component 2 to unseal or seal the explosion-proof channel 100 according to the actual situation, thereby reducing the thermal runaway of the battery.

[0078] In some of the embodiments of this application, Figure 3 As shown, judging the magnitude relationship between the gas pressure value and the set value, and controlling the switching component 3 to drive the sealing component 2 to seal or unseal the explosion-proof channel 100 according to the magnitude relationship, specifically includes:

[0079] If the gas pressure value is greater than or equal to the first set value and less than the second set value, and the temperature change of the accommodating chamber reaches the third set value and the voltage of the battery reaches the fourth set value, the switching component 3 is controlled to drive the sealing component 2 to unseal the explosion-proof channel 100 until the gas pressure value is less than the first set value and lasts for the first set time;

[0080] If the gas pressure value is greater than the second set value, the switching component 3 is controlled to drive the sealing component 2 to unseal the explosion-proof passage 100 until the gas pressure value is less than the first set value and lasts for a first set time.

[0081] It is understandable that the amount of gas released by the electrolyte in the accommodating chamber is different, and the explosion-proof valve needs to have a corresponding control strategy to reduce the consumption of the electrolyte. Among them, the amount of gas can be judged by the gas pressure value. When the gas pressure value is greater than or equal to the first set value and less than the second set value, it means that although the amount of gas in the accommodating chamber is large, it may be caused by the battery being under high load. At this time, it is necessary to judge whether the battery has deviated from its normal working range by the temperature change and the voltage. In this way, the explosion-proof channel 100 can be unsealed in time, and it is also beneficial to reduce the loss of electrolyte. If the gas pressure value is greater than the second set value, it means that the battery is more likely to be in thermal runaway, and the risk of explosion and combustion is greater. At this time, unsealing the explosion-proof channel 100 in time is beneficial to improve its safety.

[0082] In the embodiment of the present application, the first setting value may be 104 KPa, and the second setting value may be 110 KPa.

[0083] In the embodiment of the present application, in order to improve the sealing effect of the explosion-proof channel 100, the gas pressure value in the accommodating chamber can be monitored after it is unsealed. If the gas pressure value continues to drop below the first set value and lasts for more than 1 minute, the explosion-proof channel 100 is sealed in time by the switching component 3 to reduce the electrolyte consumption rate.

[0084] In the embodiment of the present application, the first set time may be 1 minute.

[0085] In the embodiment of the present application, the switching component 3 includes a coil 32, and the coil 32 and the sealing component 2 are sequentially arranged along the extension direction of the explosion-proof passage 100, and the coil 32 is used to apply a magnetic force to the sealing component 2 to unseal the explosion-proof passage 100. The switching component 3 includes a pressure sensor and a BMS (battery management system), and the BMS is electrically connected to the pressure sensor and the coil 32, and the pressure sensor is used to monitor the gas pressure value at the entrance of the explosion-proof passage 100. The switching component 3 also includes a spring 31, and the spring 31 is connected to the sealing surface 211 to apply a reset force to the sealing surface 211 to return to the explosion-proof passage 100 when the sealing surface 211 unseals the explosion-proof passage 100.

[0086] In the embodiments of the present application, Figure 4As shown, the pressure sensor periodically wakes itself up and continuously monitors the pressure changes in the containment chamber. Under normal circumstances, the pressure in the containment chamber is 1 standard atmospheric pressure, which is about 101KPa. After thermal runaway occurs, a large amount of gas is instantly generated in the containment chamber, and the gas pressure rises sharply. At this time, the pressure sensor detects that the pressure exceeds the set threshold, and will send a wake-up signal to the BMS to wake up the BMS. After the BMS is awakened by the pressure sensor, it sends a request signal to the pressure sensor, establishes a communication connection with the pressure sensor, and reads the gas pressure value. After the detected gas pressure value exceeds the threshold set by the BMS, the BMS determines that the battery pack has indeed experienced thermal runaway based on the detected voltage or temperature change. Then, it outputs a low-level signal through the control hardware circuit. The low-level signal is connected to one end of the coil 32, and the other end of the coil 32 is connected to an external 12V DC power supply system. The explosion-proof valve coil 32 is energized to generate electromagnetic suction, forcing the electronic explosion-proof valve to be fully opened, and the gas in the containment chamber is discharged to reduce the pressure of the battery.

[0087] When the battery is in normal condition, the pressure sensor will automatically wake up at regular intervals to check the gas pressure in the battery pack. When the gas pressure is normal, the BMS will not wake up. At this time, the BMS does not pass current to the coil 32, and does not generate a magnetic field and thus a magnetic force. Therefore, under the tension of the spring 31, the explosion-proof valve is in a completely closed state, isolating the accommodating cavity from the outside world.

[0088] Once thermal runaway occurs, the pressure sensor detects abnormal pressure and wakes up the BMS. The BMS immediately reads the gas pressure value to continuously monitor the pressure value in the bag. After the pressure value exceeds the first alarm threshold, the voltage and temperature values ​​are detected to reach the alarm threshold, or the pressure value is directly detected to exceed the second alarm threshold, the electronic explosion-proof valve is controlled to open and discharge the gas, and a thermal runaway alarm fault is issued to the BMS. The vehicle also issues an audible and visual alarm to remind passengers to stay away from the vehicle immediately. Among them, the first alarm threshold ranges from 104 to 110KPa, and the second alarm threshold ranges from greater than 110KPa.

[0089] If the pressure inside the battery pack continues to decrease after the explosion-proof valve is opened, and the pressure value is lower than the alarm threshold set by the BMS, if the battery pack pressure does not rise again within 1 minute, the BMS automatically enters a dormant state and disconnects the power supply of the electronic explosion-proof valve, so that the electronic explosion-proof valve closes naturally under the tension of its own spring 31 to maintain isolation between the inside and outside of the battery pack.

[0090] Taking into account the impact of the system's false alarm of valve opening, the alarm threshold of the pressure sensor can be divided into two levels. Level 1 is when the gas pressure value is ≥104KPa. At this time, the pressure sensor wakes up the BMS, and the BMS detects whether the voltage and temperature values ​​reach the alarm threshold. If both conditions are met, it is determined that the battery has thermal runaway, and the drive coil 32 is used to unseal the explosion-proof channel 100; Level 2 is when the gas pressure value is greater than 110KPa. At this time, it is determined that the battery has thermal runaway, and the drive coil 32 is used to unseal the explosion-proof channel 100, and a thermal runaway fault is reported at the same time.

[0091] In the embodiments of the present application, Figure 5 As shown, the car may include a power supply that is connected to the coil, the BMS, and the pressure sensor to power the three.

[0092] In the present application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. The term "plurality" refers to two or more than two, unless otherwise clearly defined.

[0093] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the present application disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only.

[0094] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. An explosion-proof valve, characterized in that: The explosion-proof valve comprises a valve body (1), a sealing component (2) and a switching component (3), wherein: The valve body (1) has an explosion-proof passage (100); At least a portion of the sealing assembly (2) is located in the explosion-proof passage (100) and is movable along the extension direction of the explosion-proof passage (100); The switching component (3) is connected to the sealing component (2), and the switching component (3) is configured to drive the sealing component (2) according to the gas pressure value at the entrance of the explosion-proof passage (100), so that the sealing component (2) seals or unseals the explosion-proof passage (100).

2. The explosion-proof valve according to claim 1, characterized in that: The sealing assembly (2) comprises a push rod (21), one end of the push rod (21) having a sealing surface (211), the orthographic projection of the outlet of the explosion-proof passage (100) on a projection plane is located within the orthographic projection of the sealing surface (211) on the projection plane, and the projection plane is a plane perpendicular to the extension direction of the explosion-proof passage (100).

3. The explosion-proof valve according to claim 2, characterized in that: The sealing assembly (2) comprises a sealing portion (22), the sealing portion (22) being located on a side of the sealing surface (211) facing the explosion-proof passage (100), the sealing portion (22) surrounding the push rod (21) and being annular, and the sealing portion (22) being used for abutting against the valve body (1).

4. The explosion-proof valve according to claim 2, characterized in that: The switching assembly (3) further comprises a spring (31), wherein the spring (31) is connected to the sealing surface (211) so as to apply a reset force to the sealing surface (211) to return to the explosion-proof passage (100) when the sealing surface (211) unseals the explosion-proof passage (100).

5. The explosion-proof valve according to any one of claims 1 to 4, characterized in that: The switching component (3) comprises a coil (32), wherein the coil (32) and the sealing component (2) are arranged in sequence along the extension direction of the explosion-proof passage (100), and the coil (32) is used to apply a magnetic force to the sealing component (2) to unseal the explosion-proof passage (100).

6. The explosion-proof valve according to claim 5, characterized in that: The sealing component (2) has an iron core (23) at one end facing the coil (32).

7. The explosion-proof valve according to claim 5, characterized in that: The switching component (3) comprises a pressure sensor and a control module, wherein the control module is electrically connected to the pressure sensor and the coil (32), and the pressure sensor is used to monitor the gas pressure value at the entrance of the explosion-proof passage (100).

8. A battery, characterized in that: The battery comprises a shell and an explosion-proof valve as claimed in any one of claims 1 to 7, wherein the shell has a containing cavity, and the inlet of the explosion-proof channel (100) is connected to the containing cavity.

9. A gas pressure control method, characterized in that: The gas pressure control method is applied to the battery according to claim 8, comprising: Obtaining a gas pressure value of the containing chamber; The magnitude relationship between the gas pressure value and the set value is determined, and according to the magnitude relationship, the switching component (3) is controlled to drive the sealing component (2) to seal or unseal the explosion-proof passage (100).

10. The gas pressure control method according to claim 9, characterized in that: The determining of the magnitude relationship between the gas pressure value and the set value, and controlling the switching component (3) to drive the sealing component (2) to seal or unseal the explosion-proof passage (100) according to the magnitude relationship, specifically comprises: If the gas pressure value is greater than or equal to the first set value and less than the second set value, and the temperature change of the accommodating chamber reaches a third set value and the voltage of the battery reaches a fourth set value, the switching component (3) is controlled to drive the sealing component (2) to unseal the explosion-proof passage (100) until the gas pressure value is less than the first set value and lasts for a first set time; If the gas pressure value is greater than the second set value, the switching component (3) is controlled to drive the sealing component (2) to unseal the explosion-proof passage (100) until the gas pressure value is less than the first set value and lasts for a first set time.

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