Air pressure switch, power distribution module, battery pack and thermal runaway alarm method of battery pack

Abstract

The invention relates to the technical field of air pressure switches, in particular to an air pressure switch, a power distribution module, a battery pack and a thermal runaway alarm method of the battery pack. At least part of the diaphragm assembly is conductive, the diaphragm assembly divides an inner cavity of the shell into a first cavity and a second cavity which are separated from each other, and the shell is provided with a first vent hole communicating the first cavity with the outside of the shell; the number of the connecting terminals is at least one, and the connecting terminals are arranged in the second cavity; and the diaphragm assembly is configured to move along with the air pressure difference between the first chamber and the second chamber, so that the conductive part of the diaphragm assembly is in contact with or separated from the connecting terminal. According to the air pressure switch provided by the invention, the detection sensitivity of the air pressure switch is improved, and the accuracy of pressure detection alarm is further improved.

Description

Technical Field

[0001] The present application relates to the technical field of air pressure switches, and in particular to an air pressure switch, a power distribution module, a battery pack, and a thermal runaway alarm method for a battery pack. Background Art

[0002] Sensors such as pneumatic pressure switches are important pressure sensors and actuators, widely used in various fields. Pneumatic pressure switches in related technologies typically include a pressure sensor, a core rod driven by the pressure sensor, a supporting structure that cooperates with the core rod, a transmission structure, a connecting structure, and other components. This makes the internal assembly of the pneumatic pressure switch relatively complex, and the core rod encounters significant resistance from the mating components when moving, resulting in relatively poor pressure sensing sensitivity. Such pneumatic pressure switches are more suitable for environments with large pressure differences, but are not suitable for pressure environments that require high sensing sensitivity and accuracy. Summary of the Invention

[0003] In view of the above problems, the present application provides an air pressure switch, a power distribution module, a battery pack and a thermal runaway alarm method for a battery pack, which helps to improve the detection sensitivity of the air pressure switch and thereby improve the accuracy of the air pressure detection alarm.

[0004] In a first aspect, the present application provides an air pressure switch, comprising: a housing; a diaphragm assembly, at least a portion of which is conductive, the diaphragm assembly dividing the inner cavity of the housing into a first chamber and a second chamber that are isolated from each other, the housing being provided with a first vent hole connecting the first chamber and the outside of the housing; a connecting terminal, at least one of which is arranged in the second chamber; the diaphragm assembly being constructed to move with the air pressure difference between the first chamber and the second chamber so that the conductive part of the diaphragm assembly contacts or separates from the connecting terminal.

[0005] In one possible embodiment, there are at least two connecting terminals, at least two of which are spaced apart in the second chamber, and at least two of which are respectively used to connect to an external circuit. When the diaphragm assembly moves with the air pressure difference between the first chamber and the second chamber, at least two of the connecting terminals can contact or separate from the conductive part of the diaphragm assembly.

[0006] In one possible embodiment, the diaphragm assembly includes: a conductive member, which is arranged on the side of the diaphragm assembly facing the second chamber, and the diaphragm assembly can deform under a preset pressure to drive the conductive member to move so as to contact or separate from at least two of the connecting terminals.

[0007] In a possible embodiment, the diaphragm assembly further includes: a deformable diaphragm, which is an elastic member, connected to the conductive member, and used to separate the first chamber and the second chamber, and the deformable diaphragm is constructed to deform with the air pressure difference between the first chamber and the second chamber.

[0008] In a possible embodiment, the air pressure switch further includes: an elastic return member, wherein when the diaphragm assembly moves, the diaphragm assembly abuts against the elastic return member, and the elastic return member is used to provide a force to the diaphragm assembly toward one side of the first chamber.

[0009] In a possible embodiment, the elastic return member is arranged in the first chamber and / or the second chamber, one end of the elastic return member is connected to the outer shell, and the other end cooperates with the diaphragm assembly to apply a return force to the diaphragm assembly in the opposite direction of the air pressure force.

[0010] In one possible embodiment, the housing includes: a first shell, the first shell having a first inner cavity, the diaphragm assembly is arranged in the first shell, and the diaphragm assembly divides the first inner cavity into a first sub-cavity and a second sub-cavity distributed along a first direction, wherein the first sub-cavity constitutes the first chamber, and the second sub-cavity constitutes part of the second chamber.

[0011] In a possible embodiment, the housing further includes: a second shell, the first shell and the second shell are connected along a first direction, the second shell has a second inner cavity, and the second sub-cavity and the second inner cavity are interconnected and together constitute the second chamber.

[0012] In a possible embodiment, one end of the first shell facing the second shell is formed as an opening, and the first vent is provided on a shell wall of the first shell opposite to the opening.

[0013] In a possible implementation, a communication port is provided on a side wall of the second shell facing the first shell, and the communication port connects the second sub-cavity and the second inner cavity.

[0014] In a possible implementation manner, a portion of the structure of the connecting terminal is provided in the second shell and extends from the opening into the second sub-cavity.

[0015] In a possible implementation manner, the shell is further provided with a second vent hole communicating with the second chamber and the outside of the shell.

[0016] In a possible implementation, the air pressure switch further includes: a breathable membrane covering the second vent hole and / or the first vent hole.

[0017] In a possible implementation manner, the volume of the second chamber is greater than the volume of the first chamber.

[0018] In a possible implementation, the conductive portion of the diaphragm assembly is configured as a conductive member, and when the air pressure in the first chamber and the second chamber is balanced, the conductive member and the connection terminal are spaced apart.

[0019] In one possible embodiment, the second chamber is provided with an elastic return member. When the air pressures in the first chamber and the second chamber are balanced, the distance between the conductive member and the connecting terminal is X, the elastic coefficient of the elastic return member is K, the area of ​​the surface of the diaphragm assembly facing the second chamber is S, and when the conductive member contacts the connecting terminal, the air pressure difference between the first chamber and the second chamber is , , X, K, S satisfy: .

[0020] In the second aspect, the present application provides a power distribution module, comprising: a detection circuit, which is suitable for connecting to a power supply outside the power distribution module; the above-mentioned air pressure switch, which is arranged in the detection circuit, and the detection circuit is constructed to generate a signal change when the diaphragm assembly of the air pressure switch is connected to or disconnected from the connection terminal; a chip unit, which is arranged in the detection circuit, and is used to detect the signal change of the detection circuit to detect whether an abnormality occurs.

[0021] In a possible embodiment, the chip unit includes: an SBC chip connected to the power supply; a main control chip connected to the SBC chip, and the SBC chip is used to power the main control chip; the air pressure switch is arranged between the power supply and the SBC chip to control the on and off between the power supply and the SBC chip.

[0022] In a possible embodiment, the power distribution module further includes: a resistance element, which is connected in series with the air pressure switch and then in parallel with the two ends of the power supply, and the main control chip is connected in parallel with the resistance element to collect the voltage across the two ends of the resistance element; the main control chip issues a thermal runaway alarm instruction when the voltage across the two ends of the resistance element is greater than or equal to a preset voltage value.

[0023] In a possible implementation manner, the preset voltage value is 6V-18V.

[0024] In a third aspect, the present application provides a battery pack, comprising: a box body having a accommodating cavity; a battery module disposed in the accommodating cavity; the above-mentioned power distribution module, and / or the above-mentioned air pressure switch, wherein the first vent of the air pressure switch is connected to the accommodating cavity.

[0025] In a possible embodiment, the accommodating cavity includes: a battery cavity and a power distribution cavity, the battery cavity and the power distribution cavity are connected to each other, the battery cavity is suitable for arranging the battery module, and the power distribution cavity is suitable for arranging the power distribution module.

[0026] In a fourth aspect, the present application provides a thermal runaway alarm method for a battery pack, comprising the following steps: determining that the air pressure switch is turned on; the SBC chip supplies power to the main control chip; the main control chip obtains the voltage value across the resistance element; when the voltage value exceeds a preset voltage value, the main control chip issues a thermal runaway alarm instruction.

[0027] The air pressure switch, power distribution module, battery pack, and thermal runaway alarm method for the battery pack provided by the present application use a diaphragm assembly to separate the inner cavity of the housing into a first chamber and a second chamber. The diaphragm assembly moves under the action of the air pressure difference between the first chamber and the second chamber to control the contact or separation of the diaphragm assembly and the connection terminal, thereby realizing the perception of pressure changes. Compared with the air pressure switch in the related art that uses many components such as a pressure sensing element, a core rod driven by the pressure sensing element, and a support structure that cooperates with the core rod, the diaphragm assembly of this solution has a simpler structure, and the resistance and constraints from other structures on the movement of the diaphragm assembly are greatly reduced, which can improve the sensitivity and accuracy of the diaphragm assembly in sensing pressure, and is more suitable for pressure environments that require high sensing sensitivity to pressure fluctuations.

[0028] Furthermore, when the air pressure switch is used as a circuit switch for the battery pack, since the air pressure switch can directly sense the air pressure changes in the battery pack, when the battery experiences thermal runaway and causes the air pressure to change, the diaphragm assembly can connect to the connection terminal and promptly transmit the signal to the external circuit to feedback the status of the battery pack.

[0029] In addition, the working mode of the air pressure switch is not affected by whether the battery pack is in the charging and / or discharging state. Even if the battery pack is in a dormant period, the air pressure switch can sense and respond to the air pressure changes in the battery pack in a timely manner, which is conducive to ensuring the alarm accuracy and safety of the battery pack in the entire cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0031] Figure 1 Schematic diagram of the structure of the air pressure switch provided in this application Figure 1 ;

[0032] Figure 2 Schematic diagram of the structure of the air pressure switch provided in this application Figure 2 ;

[0033] Figure 3 A circuit diagram of the power distribution module provided for this application;

[0034] Figure 4 A schematic diagram of the structure of the battery pack provided for this application;

[0035] Figure 5 This is a flow chart of the thermal runaway alarm method for the battery pack provided in this application.

[0036] Description of reference numerals:

[0037] 1-Battery pack;

[0038] 10-box; 11-accommodation cavity; 111-battery cavity; 112-distribution cavity;

[0039] 20-battery module;

[0040] 30-power distribution module; 31-air pressure switch; 32-SBC chip; 33-main control chip; 34-resistance element;

[0041] 311 - housing; 3111 - first chamber; 3112 - second chamber; 3113 - first vent; 3114 - first shell; 3114a - first inner chamber; 3114b - open port; 3114a1 - first sub-chamber; 3114a2 - second sub-chamber; 3115 - second shell; 3115a - second inner chamber; 3115b - communication port; 3116 - second vent; 3116a - breathable membrane;

[0042] 312-diaphragm assembly; 3121-deformable diaphragm; 3122-conductive member;

[0043] 313-connection terminal;

[0044] 314-Elastic reset element.

[0045] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0046] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0047] Sensors such as pneumatic pressure switches are important pressure sensors and actuators, widely used in various fields. Pneumatic pressure switches in related technologies typically include a pressure sensor, a core rod driven by the pressure sensor, a supporting structure that cooperates with the core rod, a transmission structure, a connecting structure, and other components. This makes the internal assembly of the pneumatic pressure switch relatively complex, and the core rod encounters significant resistance from the mating components when moving, resulting in relatively poor pressure sensing sensitivity. Such pneumatic pressure switches are more suitable for environments with large pressure differences or large pressure fluctuations, but are not suitable for pressure environments with relatively small pressure fluctuations that require higher sensing sensitivity and accuracy.

[0048] In view of this, the present application provides an air pressure switch, a power distribution module, a battery pack, and a thermal runaway alarm method for the battery pack. The diaphragm assembly moves under the influence of the air pressure difference between the first chamber and the second chamber to control the contact or separation between the diaphragm assembly and the connection terminal, thereby realizing the perception of pressure changes. Furthermore, the diaphragm assembly of this solution has a relatively simple structure, and the air pressure switch has fewer internal components. The resistance and constraints imposed on the diaphragm assembly by other structures are greatly reduced, which can improve the sensitivity and accuracy of the diaphragm assembly in sensing pressure, making it more suitable for pressure environments that require high sensitivity to pressure fluctuations.

[0049] It can be understood that the air pressure switch provided in this application can be applied to ternary lithium battery power systems, lithium iron phosphate battery power systems, etc.

[0050] For ease of description, the first direction may refer to the Y direction, or the first direction may refer to the moving direction of the diaphragm assembly, and the second direction may refer to the X direction.

[0051] Reference below Figure 1 、 Figure 2 The air pressure switch 31 provided in the embodiment of the present application includes a housing 311 , a diaphragm assembly 312 and a connecting terminal 313 .

[0052] The housing 311 supports and protects the diaphragm assembly 312 and connection terminals 313 within the air pressure switch 31. Furthermore, the housing 311 provides mounting space for the diaphragm assembly 312 and connection terminals 313. The housing 311 has an interior cavity. The diaphragm assembly 312 can be disposed within the interior cavity, dividing the interior cavity of the housing 311 into a first chamber 3111 and a second chamber 3112, which are isolated from each other.

[0053] The diaphragm assembly 312 may be a conductive member; alternatively, a portion of the diaphragm assembly 312 may be conductive. A first vent 3113 is also provided on the housing 311. The first vent 3113 can connect the first chamber 3111 with the exterior of the housing 311. The exterior of the housing 311 refers to the interior space of the battery pack 1 outside the air pressure switch 31. That is, the first vent 3113 can connect the first chamber 3111 with the interior space of the battery pack 1. In this way, changes in the air pressure inside the battery pack 1 can affect the air pressure in the first chamber 3111 and the second chamber 3112. The diaphragm assembly 312 is constructed to move with the air pressure difference between the first chamber 3111 and the second chamber 3112. Furthermore, after the air pressures in the first chamber 3111 and the second chamber 3112 are balanced, the diaphragm assembly 312 can be reset.

[0054] Optionally, the diaphragm assembly 312 can be a multi-layer composite structure diaphragm. For example, the diaphragm assembly 312 can be composed of a layer of elastic rubber membrane and a layer of metal foil. The elastic rubber membrane can provide good elastic deformation ability, while the metal foil can play a role in conducting electricity and enhancing structural strength. When the air pressure difference acts on the diaphragm assembly 312, the elastic rubber membrane can deform, thereby driving the metal foil to move, thereby changing the on-off state of the connecting terminal 313. Moreover, after the air pressure in the first chamber 3111 and the second chamber 3112 is balanced, the diaphragm assembly 312 can be reset under the elastic force of the elastic rubber membrane. This multi-layer composite structure can adjust the materials of each layer and the thickness and performance of each layer according to actual needs to optimize the response sensitivity and stability of the diaphragm assembly 312. Of course, the present application is not limited to this, and the specific materials and characteristics of the diaphragm assembly 312 can be set according to the product usage scenario.

[0055] Furthermore, a connection terminal 313 may be provided within the second chamber 3112. This connection terminal 313 is a conductive terminal, meaning that it can serve as the circuit connection structure of the air pressure switch 31 and connect to an external circuit. There is at least one connection terminal 313, meaning there can be one or more connection terminals, with "more" meaning two or more. The diaphragm assembly 312 is configured to move in response to the air pressure difference between the first chamber 3111 and the second chamber 3112, so that the conductive portion of the diaphragm assembly 312 contacts or separates from the connection terminal 313.

[0056] It is understandable that since the diaphragm assembly 312 has a conductive portion, and the connection terminals 313 can also serve as a circuit connection structure on the air pressure switch 31 for connecting to an external circuit, when the air pressure switch 31 of this embodiment is used as a circuit switch, the connection method between the air pressure switch 31 and the external circuit can be selected according to the number of connection terminals 313. For example, as follows:

[0057] When the air pressure switch 31 is provided with a connection terminal 313, both the connection terminal 313 and the conductive portion of the diaphragm assembly 312 can be used to connect to an external circuit. The conductive portion of the diaphragm assembly 312 (referred to below as the conductive member 3122) can be directly connected to one electrode of the external circuit. The connection terminal 313 can be directly connected to another electrode of the external circuit. In this way, when the diaphragm assembly 312 moves toward the connection terminal 313 due to the pressure difference between the first chamber 3111 and the second chamber 3112, the conductive portion of the diaphragm assembly 312 can contact the connection terminal 313 to form a pathway. When the pressures are balanced, the diaphragm assembly 312 can separate from the connection terminal 313 to isolate the circuit.

[0058] Alternatively, if the air pressure switch 31 is provided with at least two connection terminals 313, using the connection terminals 313 as an example, the two connection terminals 313 can be spaced apart in the second chamber 3112. The two connection terminals 313 can be connected to different electrodes of the external circuit. In this way, when the diaphragm assembly 312 moves in response to the air pressure difference between the first chamber 3111 and the second chamber 3112, the diaphragm assembly 312 can contact or separate from the two connection terminals 313, thereby connecting or disconnecting the external circuit connected to the two connection terminals 313.

[0059] The connection terminal 313 can be designed in a needle or column shape. To ensure that the connection terminal 313 does not loosen due to vibration, impact, or other factors during the operation of the air pressure switch 31, a fixing structure such as a thread or a snap can be provided on the connection terminal 313. For example, one end of the connection terminal 313 can have an external thread that can be screwed onto the inner wall of the second chamber 3112.

[0060] The air pressure switch 31 of the embodiment of the present application uses a diaphragm assembly 312 to separate the inner cavity of the housing 311 into a first chamber 3111 and a second chamber 3112. The diaphragm assembly 312 moves under the action of the air pressure difference between the first chamber 3111 and the second chamber 3112 to control the contact or separation between the diaphragm assembly 312 and the connecting terminal 313, thereby realizing the perception of pressure changes. Compared with the air pressure switch in the related art that uses a pressure sensing element, a core rod driven by the pressure sensing element, a supporting structure that cooperates with the core rod, and many other components, the diaphragm assembly 312 of this solution has a simpler structure and a smaller number of components inside the air pressure switch 31. The resistance and constraints on the movement of the diaphragm assembly 312 from other structures are greatly reduced, which can improve the sensitivity and accuracy of the diaphragm assembly 312 in sensing pressure, and is more suitable for pressure environments that require high sensing sensitivity to pressure fluctuations.

[0061] Furthermore, when the air pressure switch 31 is used as a circuit switch of the battery pack, since the air pressure switch 31 can directly sense the air pressure changes in the battery pack 1, when the battery has thermal runaway and causes the air pressure to change, the diaphragm assembly 312 can connect to the connection terminal 313 to promptly transmit the signal to the external circuit to feedback the status of the battery pack.

[0062] In addition, the working mode of the air pressure switch 31 is not affected by whether the battery pack is in a charging and / or discharging state. Even if the battery pack is in a dormant period, the air pressure switch 31 can sense and respond to the air pressure changes in the battery pack in a timely manner, which is beneficial to ensure the alarm accuracy and safety of the battery pack in the entire cycle.

[0063] In one possible embodiment, the diaphragm assembly 312 includes a conductive member 3122. The conductive member 3122 may be disposed on a side of the diaphragm assembly 312 facing the second chamber 3112. The diaphragm assembly 312 can deform under a preset pressure to move the conductive member 3122, thereby allowing the conductive member 3122 to contact or separate from the at least two connection terminals 313.

[0064] In one possible embodiment, the diaphragm assembly 312 further includes a deformable diaphragm 3121. The deformable diaphragm 3121 can be used to separate the inner cavity of the housing 311 to divide the inner cavity into a first chamber 3111 and a second chamber 3112. The deformable diaphragm 3121 is constructed to deform with the air pressure difference between the first chamber 3111 and the second chamber 3112. A conductive member 3122 can be provided on the deformable diaphragm 3121. The conductive member 3122 can be provided on the side of the deformable diaphragm 3121 facing the second chamber 3112. During the deformation process, the deformable diaphragm 3121 can drive the conductive member 3122 to move to achieve contact and separation with the connecting terminal 313. Optionally, the conductive member 3122 can be a sheet-like structure to increase the contact area with the connecting terminal 313, reduce the contact resistance, and make the circuit conduction more stable. A groove structure can also be provided on the conductive member 3122. The groove structure corresponds to the connection terminal 313 to achieve a tight connection and avoid poor contact.

[0065] In one possible embodiment, the elastic return member 314 can be provided in the first chamber 3111 or the second chamber 3112. In addition, one end of the elastic return member 314 is connected to the outer shell 311. The other end of the elastic return member 314 elastically cooperates with the diaphragm assembly 312 to apply a return force on the diaphragm assembly 312 in the opposite direction of the air pressure force. By providing the elastic return member 314, when the air pressure in the first chamber 3111 and the second chamber 3112 is balanced, that is, when the battery pack does not have thermal runaway, the elastic return member 314 is conducive to keeping the diaphragm assembly 312 in place, and also avoids the diaphragm assembly 312 from contacting the connecting terminal 313 due to unexpected factors other than thermal runaway.

[0066] For example, the elastic return member 314 can be disposed within the first chamber 3111. Furthermore, one end of the elastic return member 314 is connected to the housing 311, and the other end of the elastic return member 314 is connected to the diaphragm assembly 312. In this way, when the diaphragm assembly 312 moves due to the pressure difference between the first chamber 3111 and the second chamber 3112, the elastic return member 314 can provide a pulling force to the diaphragm assembly 312 toward the first vent 3113.

[0067] Alternatively, the elastic return member 314 can be arranged in the second chamber 3112. In addition, one end of the elastic return member 314 can be connected to the housing 311, and the other end of the elastic return member 314 can be in free contact with the diaphragm assembly 312. That is, when the air pressure is balanced, the other end of the elastic return member 314 can be spaced apart from the diaphragm assembly 312. Only when the diaphragm assembly 312 moves with the air pressure difference between the first chamber 3111 and the second chamber 3112 does the other end of the elastic return member 314 come into contact with the diaphragm assembly 312. In addition, after the diaphragm assembly 312 moves with the air pressure difference between the first chamber 3111 and the second chamber 3112, the elastic return member 314 can provide a thrust to the diaphragm assembly 312 toward the first vent 3113.

[0068] In one possible embodiment, the housing 311 includes a first housing 3114 and a second housing 3115. The first housing 3114 and the second housing 3115 are arranged along a first direction and are interconnected. Furthermore, the first housing 3114 has a first inner cavity 3114a, and the second housing 3115 has a second inner cavity 3115a. The diaphragm assembly 312 may be disposed within the first housing 3114. In this manner, the diaphragm assembly 312 can separate the first inner cavity 3114a of the first housing 3114 into a first sub-cavity 3114a1 and a second sub-cavity 3114a2. The first sub-cavity 3114a1 and the second sub-cavity 3114a2 are also arranged along the first direction.

[0069] Among them, the first sub-cavity 3114a1 can serve as the first chamber 3111. The second sub-cavity 3114a2 and the second inner cavity 3115a are interconnected and together serve as the second chamber 3112. The volume of the second chamber 3112 is greater than the volume of the first chamber 3111. Furthermore, the volume of the second chamber 3112 is much greater than the volume of the first chamber 3111. That is, regardless of whether the diaphragm assembly 312 moves, the volume of the second chamber 3112 is greater than the volume of the first chamber 3111. Optionally, the first shell 3114 and the second shell 3115 can be connected by threads or snaps. The shape of the first inner cavity 3114a can correspond to the diaphragm assembly 312 to facilitate the movement of the diaphragm assembly 312 within the first inner cavity 3114a.

[0070] In one possible embodiment, in order to communicate with the external environment, a first air vent 3113 is provided on the first shell 3114. In order to communicate with the second shell 3115, an opening 3114b is provided on the first shell 3114. The opening 3114b can be provided at one end of the first shell 3114 facing the second shell 3115. The first air vent 3113 can be provided on the shell wall at the other end of the first shell 3114. The first air vent 3113 and the opening 3114b are relatively distributed along the first direction. The size of the first air vent 3113 can be related to factors such as the sensitivity and response speed of the diaphragm assembly 312, the volume of the first chamber 3111 and the second chamber 3112, etc. The size of the first air vent 3113 can be determined according to actual needs and is not limited by this application.

[0071] In one possible embodiment, a communication port 3115b is provided on the second housing 3115. Specifically, the communication port 3115b is provided on a side wall of the second housing 3115 facing the first housing 3114. The communication port 3115b corresponds to the opening 3114b, so that the communication port 3115b can connect the second sub-cavity 3114a2 with the second inner cavity 3115a.

[0072] It is understood that the second sub-cavity 3114a2 and the second inner cavity 3115a, as components of the second chamber 3112, may experience some local pressure differences. The presence of the communication port 3115b can balance these local pressure differences to a certain extent, preventing local pressures from being too high or too low. The corresponding arrangement of the communication port 3115b and the opening 3114b ensures that the pressure from the second chamber 3112 is more uniform during the movement of the diaphragm assembly 312, reducing abnormal stress or deformation of the diaphragm assembly 312 caused by local pressure imbalances. When the diaphragm assembly 312 moves in response to the pressure difference, the design of the communication port 3115b and the opening 3114b ensures that the pressure from the second chamber 3112 is applied to the diaphragm assembly 312 in a more stable manner, improving the reliability and consistency of the diaphragm assembly 312's operation, thereby ensuring that the connection terminal 313 of the air pressure switch 31 can accurately perform the conduction or isolation operation according to the movement of the diaphragm assembly 312.

[0073] In one possible embodiment, the connecting terminal 313 may be disposed in the second shell 3115. Alternatively, a partial structure of the connecting terminal 313 may be disposed in the second shell 3115. Specifically, the connecting terminal 313 may be relatively disposed along the second direction in the second shell 3115. Furthermore, one end of the connecting terminal 313 may extend from the opening 3114b into the second sub-cavity 3114a2. Optionally, the connecting terminal 313 may include a main body and a connecting portion. The main body of the connecting terminal 313 may be disposed on the inner wall of the second shell 3115 to ensure the stability of the connecting terminal 313. For example, the main body of the connecting terminal 313 may be fixed by providing a slot on the inner wall of the second shell 3115 or using a fastening screw to withstand various mechanical stresses generated by the battery pack 1 during use.

[0074] To ensure a smooth connection with an external circuit, the main body of the connecting terminal 313 can extend out of the second housing 3115, exposing a portion of the main body outside the second housing 3115. This facilitates connection with external wires, circuit boards, or other electrical components. One end of the connecting portion of the connecting terminal 313 is connected to the main body, while the other end can extend through the communication port 3115b of the second housing 3115 and into the second sub-cavity 3114a2 through the opening 3114b. This ensures that the diaphragm assembly 312 can contact the first chamber 3111 and the second chamber 3112 when a pressure differential is generated between the first chamber 3111 and the second chamber 3112.

[0075] In one possible embodiment, the housing 311 is further provided with a second vent hole 3116. The second vent hole 3116 can be disposed on the wall of the second housing 3115 at an end opposite the communication opening 3115b. The second vent hole 3116 can connect the second chamber 3112 with the exterior of the housing 311. Optionally, the second vent hole 3116 can be smaller than the first vent hole 3113.

[0076] It will be appreciated that since the first vent 3113 in the first housing 3114 connects the first chamber 3111 with the outside world (the interior of the battery pack 1), and the second vent 3116 in the second housing 3115 connects the second chamber 3112 with the outside world (the interior of the battery pack 1), when the air pressure inside the battery pack 1 changes, the air pressure inside the battery pack 1 acts on the first chamber 3111 and the second chamber 3112, respectively. Because the second vent 3116 is smaller than the first vent 3113, the air pressure in the second chamber 3112 adjusts relatively slowly. This difference creates a pressure differential between the first chamber 3111 and the second chamber 3112, compared to the first chamber 3111. When thermal runaway occurs within the battery pack 1, the first chamber 3111 can quickly sense changes in external air pressure through the first vent 3113, while the second chamber 3112 adjusts its air pressure relatively slowly through the smaller second vent 3116. This results in a pressure differential between the first chamber 3111 and the second chamber 3112. The formation and duration of this pressure differential can be adjusted based on the size of the second vent 3116, allowing the diaphragm assembly 312 to deform in a more controllable manner, thereby triggering the conduction or isolation operation of the connection terminal 313, thereby improving the accuracy of the air pressure switch 31's response to air pressure changes.

[0077] In one possible embodiment, the air pressure switch 31 further includes a breathable membrane 3116a. The breathable membrane 3116a can cover the second vent 3116 and / or the first vent 3113. For example, when the first vent 3113 is in communication with the exterior of the housing 311, the breathable membrane 3116a can cover the second vent 3116; when the second vent 3116 is in communication with the exterior of the housing 311, the breathable membrane 3116a can cover the first vent 3113. The breathable membrane 3116a can be a waterproof breathable membrane. Alternatively, the breathable membrane 3116a can be a polytetrafluoroethylene (PTFE) breathable membrane, an expanded polytetrafluoroethylene (EPTFE) breathable membrane, or the like. Thus, by providing the breathable membrane 3116a, the air intake rate of the adjacent chamber can be slowed, thereby ensuring a pressure difference between the first chamber 3111 and the second chamber 3112.

[0078] In the specific implementation process, the design criteria of the air pressure switch 31 need to meet the following criteria: On the one hand, when the battery undergoes thermal runaway, the gas generated will cause the air pressure in the battery pack 1 to rise. At this time, the air pressure difference on both sides of the air pressure switch 31 must reach the conduction threshold to achieve the corresponding function. On the other hand, when the car is traveling from a low altitude to a high altitude, it will also cause the air pressure in the battery pack 1 to rise. However, in this case, the air pressure switch 31 should not be turned on to avoid false alarms. It is worth noting that the air pressure increase caused by thermal runaway and altitude changes is different in rate, and the design of the air pressure switch 31 can take advantage of this difference to achieve its reliable performance.

[0079] Specifically, experimental data shows that when the batteries in battery pack 1 experience thermal runaway, the gases generated by the batteries can increase the air pressure in battery pack 1 by at least 5kPa within 3 seconds. In contrast, when a car is traveling from a low altitude to a high altitude, assuming a 10° road slope and a vehicle speed of 100km / h, it takes 144s for the air pressure in battery pack 1 to increase by 5kPa. Based on the aforementioned differences in the rate of change of air pressure, when designing the air pressure switch 31, it is necessary to ensure that when the air pressure increases at a rate of 5kPa / 3s, the air pressure switch 31 can conduct; and when the air pressure increases at a rate of 5kPa / 144s, the air pressure switch 31 remains disconnected, thereby achieving accurate monitoring and response to battery thermal runaway.

[0080] In a possible implementation, when the air pressures in the first chamber 3111 and the second chamber 3112 are kept in a balanced state, the conductive member 3122 may be spaced apart from the connection terminal 313 .

[0081] In one possible embodiment, when the air pressure in the first chamber 3111 and the second chamber 3112 is kept in a balanced state, there is a gap between the conductive member 3122 and the connecting terminal 313. The gap between the conductive member 3122 and the connecting terminal 313 can be represented by X. The elastic coefficient of the elastic return member 314 can be K. The area of ​​the surface of the side of the diaphragm assembly 321 facing the second chamber 3112 can be S. When there is an air pressure difference between the first chamber 3111 and the second chamber 3112, so that the conductive member 3122 contacts the connecting terminal 313, the air pressure difference between the first chamber 3111 and the second chamber 3112 can be . Further lower, X, K, S, satisfy: . Wherein, the range of ΔP1 can be 2.5kPa-4kPa. Optionally, That is, when the pressure difference between the first chamber 3111 and the second chamber 3112 reaches 3 kPa, the conductive member 3122 may contact the connection terminal 313 .

[0082] In one possible embodiment, the volume of the first chamber 3111 may be V1. The aperture of the first vent 3113 may be R1. The volume of the second chamber 3112 may be V2. The aperture of the second vent 3116 may be R2. The air permeability of the air permeable membrane 3116a may be W. Wherein, V1, R1, V2, R2, and W satisfy the following relationship:

[0083] ,

[0084] Wherein, Pe(t,f) is the law of change of air pressure over time when the ambient air pressure increases to the target pressure within the first preset time. t represents the first preset time. f represents the rate of change of air pressure when it increases by 5 kPa within 3 seconds. C1 represents the integral constant of the first chamber. C2 represents the integral constant of the second chamber. The numerical range of m is 2≤m≤60. For example, m can be 2, 3, 4, 6, 8, 10, 20, 30, 40, 50 or 60. Of course, the present application is not limited to this. The numerical range of m can be selected according to the environment.

[0085] V1, R1, V2, R2 and W also satisfy the following relationship:

[0086] ,

[0087] Where Pe(t,s) is the temporal variation of the ambient pressure when the ambient pressure increases to the target pressure within the second preset time. t represents the second preset time. s represents the rate of change of the pressure when the pressure increases by 5 kPa in 144 seconds. C1 represents the integration constant of the first chamber. C2 represents the integration constant of the second chamber.

[0088] In this way, the air pressure switch 31 is ensured to accurately monitor and respond to battery thermal runaway, avoiding false alarms caused by normal air pressure fluctuations such as altitude changes.

[0089] In one possible embodiment, if the second housing 3115 is provided with a second vent hole 3116, the first preset time may be 2 seconds to 10 seconds. For example, the first preset time may be 2 seconds, 3 seconds, 4 seconds, 5 seconds, 6 seconds, 7 seconds, 8 seconds, 9 seconds, or 10 seconds. The second preset time may be 120 seconds to 160 seconds. For example, the second preset time may be 120 seconds, 130 seconds, 140 seconds, 150 seconds, or 160 seconds. The target pressure may be 3 kPa to 7 kPa. For example, the target pressure may be 3 kPa, 4 kPa, 5 kPa, 6 kPa, or 7 kPa. If the second housing 3115 is not provided with a second vent hole 3116, the first preset time may be 2 seconds to 10 seconds. For example, the first preset time may be 2 seconds, 3 seconds, 4 seconds, 5 seconds, 6 seconds, 7 seconds, 8 seconds, 9 seconds, or 10 seconds. The target pressure may be 3 kPa to 7 kPa. For example, the target pressure may be 3 kPa, 4 kPa, 5 kPa, 6 kPa, or 7 kPa. The specific values ​​of the first preset time, the second preset time, and the target pressure may be determined according to actual needs and are not limited in this application.

[0090] Further, refer to Figure 3The present application provides a power distribution module 30, comprising a detection circuit, the above-mentioned air pressure switch 31 and a chip unit. The detection circuit is suitable for connecting to a power source outside the power distribution module 30. Among them, the air pressure switch 31 can be arranged in the detection circuit. In this way, the detection circuit can generate a signal change when the diaphragm assembly 312 of the air pressure switch 31 is connected or disconnected from the connection terminal 313. The chip unit can also be arranged in the detection circuit. The chip unit can detect the signal change of the detection circuit to detect whether an abnormality occurs, and the abnormality here includes thermal runaway.

[0091] In one possible implementation, the chip unit may include a system basis chip (SBC) and a main control chip 33. Hereinafter, the term "SBC" refers to the system basis chip. The SBC chip 32 may be connected to a power source external to the power distribution module 30. Furthermore, the SBC chip 32 may be connected to the main control chip 33. The SBC chip 32 is used to supply power to the main control chip 33. To control the connection between the power source and the SBC chip 32, a gas pressure switch 31 may be provided between the power source and the SBC chip 32.

[0092] It is understood that the aforementioned air pressure switch 31 can be positioned between the power supply and the SBC chip 32 to control the connection between the power supply and the SBC chip 32. When the air pressure within the battery pack 1 is within a normal range, the air pressure switch 31 is in an off state, severing the circuit between the power supply and the SBC chip 32 and preventing current from flowing. However, if the battery pack 1 experiences thermal runaway, causing the air pressure to change, the air pressure switch 31 will be on, establishing a path between the power supply and the SBC chip 32, allowing current to flow through the air pressure switch 31.

[0093] In one possible embodiment, the power distribution module 30 further includes a resistor element 34. The resistor element 34 can be connected in series with the air pressure switch 31 and then connected in parallel to both ends of the power supply. At the same time, the main control chip 33 can be connected in parallel with the resistor element 34 to collect the voltage across the resistor element 34. The main control chip 33 can issue a thermal runaway alarm instruction when the voltage across the resistor element 34 is greater than or equal to a preset voltage value. Optionally, the preset voltage value is 6V-18V. For example, the preset voltage value can be 6V, 7V, 8V, 9V, 10V, 11V, 12V, 13V, 14V, 15V, 16V, 17V, or 18V. The preset voltage value can be determined based on the actual usage scenario, and this application does not impose any restrictions.

[0094] During the specific implementation process, when the air pressure switch 31 is turned on, current will pass through the resistor element 34, and due to the presence of the resistor, a voltage will be generated at both ends of the resistor element 34. The main function of the resistor element 34 is to convert the on / off state of the air pressure switch 31 into a measurable voltage signal. The change in the voltage at both ends of the resistor element 34 provides a monitorable physical quantity for the subsequent main control chip 33. The main control chip 33 monitors the voltage at both ends of the resistor element 34, and then determines the on / off state of the air pressure switch 31, thereby inferring whether thermal runaway has occurred in the battery pack 1. In addition, the main control chip 33 can issue a thermal runaway alarm instruction when the voltage at both ends of the resistor element 34 is greater than or equal to a preset voltage value.

[0095] Furthermore, when the air pressures in the first chamber 3111 and the second chamber 3112 are relatively balanced, the air pressure switch 31 is in an off state, the circuit in which the air pressure switch 31 is located is blocked, no current flows through the resistor 34, and the voltage across it is zero. When the battery pack 1 experiences thermal failure, resulting in an air pressure difference between the first chamber 3111 and the second chamber 3112, and the air pressure difference reaches a preset threshold, and the rate of change of the air pressure reaches a preset condition, the air pressure switch 31 turns on, forming a path in the circuit in which the air pressure switch 31 is located, and current flows through the resistor 34. Due to the resistance of the resistor 34, when current passes through it, a voltage is generated across the resistor 34. The voltage change across the resistor 34 can convert the mechanical structural change of the air pressure switch 31 (the change in the on / off state) into a monitorable electrical signal (the voltage across the resistor 34). The main control chip 33 can continuously monitor the voltage across the resistor element 34. Once it detects that the voltage across the resistor element 34 exceeds a preset voltage value, indicating that the air pressure switch 31 has been turned on, the main control chip 33 will issue a thermal runaway alarm instruction.

[0096] It can be understood that the series design of the air pressure switch 31 and the resistor element 34, combined with the power supply logic of the SBC chip 32 and the main control chip 33, enables power-free thermal runaway detection. This functionality also allows thermal runaway detection during the battery pack 1's dormant period. Specifically, when the battery pack 1 is operating normally, the air pressure switch 31 is physically isolated due to the balanced air pressure between the internal and external chambers, thereby disconnecting the circuit between the power supply and the SBC chip 32, leaving the detection circuit in a zero-current, zero-power state. When the battery pack 1 experiences thermal runaway, the sudden change in internal air pressure triggers the air pressure switch 31 to conduct. Current flows through the air pressure switch 31 and the series resistor element 34, generating a voltage signal. The main control chip 33 monitors this voltage in real time and compares it with a preset threshold. Once the threshold is exceeded, an alarm is triggered. The entire process activates the circuit only when the battery pack 1 experiences an abnormality, utilizing the mechanical response characteristics of air pressure instead of continuous electronic monitoring. This not only avoids continuous energy loss in the detection circuit but also prevents missed detections during system dormancy. That is, traditional electronic detectors or sensors require continuous power supply. When the system is dormant, the electronic detectors or sensors may be in a closed state, making it impossible to perform thermal runaway detection. Figure 4 The present application also provides a battery pack 1, comprising a case 10, a battery module 20 and the above-mentioned power distribution module 30. The case 10 is provided with a accommodating cavity 11. The battery module 20 and the above-mentioned power distribution module 30 can both be arranged in the accommodating cavity 11. The above-mentioned air pressure switch 31 can be provided in the power distribution module 30. Moreover, the first air vent 3113 of the air pressure switch 31 can be in communication with the accommodating cavity 11. Alternatively, the first air vent 3113 and the second air vent 3116 of the air pressure switch 31 can both be in communication with the accommodating cavity 11.

[0097] Alternatively, the battery pack 1 of the present application may further include a housing 10, a battery module 20, the aforementioned power distribution module 30 and / or the aforementioned air pressure switch 31. The housing 10 is provided with a housing chamber 11. The battery module 20, the aforementioned power distribution module 30, and the air pressure switch 31 may all be disposed within the housing chamber 11. That is, the air pressure switch 31 may also be disposed outside the power distribution module 30. Furthermore, the first air vent 3113 of the air pressure switch 31 may be in communication with the housing chamber 11. Alternatively, the first air vent 3113 and the second air vent 3116 of the air pressure switch 31 may both be in communication with the housing chamber 11. In one possible embodiment, the housing chamber 11 includes a battery chamber 111 and a power distribution chamber 112. The battery module 20 may be disposed within the battery chamber 111. The power distribution module 30 may be disposed within the power distribution chamber 112. Furthermore, the battery chamber 111 and the power distribution chamber 112 are in communication with each other. Alternatively, the air pressure switch 31 may be disposed within the battery chamber 111. Alternatively, the gas pressure switch 31 may be disposed within the power distribution cavity 112. Alternatively, the first housing 3114 of the gas pressure switch 31 may be disposed within the battery cavity 111, and the second housing 3115 of the gas pressure switch 31 may be disposed within the power distribution cavity 112. Still further, the first housing 3114 of the gas pressure switch 31 may be disposed within the power distribution cavity 112, and the second housing 3115 of the gas pressure switch 31 may be disposed within the battery cavity 111.

[0098] Further, refer to Figure 5 The present application also provides a thermal runaway alarm method for a battery pack 1, comprising the following steps:

[0099] S1. Determine whether the air pressure switch 31 is turned on.

[0100] In the specific implementation process, whether the air pressure switch 31 is turned on or off depends on the air pressure conditions in the battery pack 1. Under normal circumstances, the air pressure in the battery pack 1 is in a relatively stable state, the air pressure between the first chamber 3111 and the second chamber 3112 is balanced, and the air pressure switch 31 is in the disconnected state. However, when the battery pack 1 experiences thermal runaway, a large amount of gas will be generated, causing the air pressure in the battery pack 1 to rise rapidly. This change in air pressure will break the air pressure balance between the first chamber 3111 and the second chamber 3112, causing the diaphragm assembly 312 therein to move accordingly. As the air pressure difference increases, the diaphragm assembly 312 will be displaced. When a certain displacement is reached, the conductive member 3122 contacts the connecting terminal 313, so that the circuit where the air pressure switch 31 is located is connected, thereby realizing the transition from the disconnected state to the on state.

[0101] Alternatively, the conduction of the air pressure switch 31 can be determined by monitoring whether current flows in a circuit connected in series with the air pressure switch 31. Alternatively, an auxiliary status detection pin can be provided on the air pressure switch 31. When the air pressure switch 31 is on, the pin outputs a specific level signal to determine whether the air pressure switch 31 is on.

[0102] S2 , the SBC chip 32 supplies power to the main control chip 33 .

[0103] In a specific implementation, the air pressure switch 31 can be connected in series between the power supply and the SBC chip 32. This way, when the air pressure switch 31 is in the off state, the circuit between the power supply and the SBC chip 32 is severed, preventing the SBC chip 32 from receiving power from the power supply. When the air pressure switch 31 is on, a circuit is established between the power supply and the SBC chip 32, allowing the SBC chip 32 to operate normally. Simultaneously, the power output pin of the SBC chip 32 is connected to the power input pin of the main control chip 33. Thus, when the air pressure switch 31 is on, the SBC chip 32 can provide a stable operating power supply to the main control chip 33.

[0104] S3 . The main control chip 33 obtains the voltage value across the resistor 34 .

[0105] In a specific implementation, after the main control chip 33 is powered and activated by the SBC chip 32, it monitors the voltage across the resistor 34 when the gas pressure switch 31 is in the on state. The main control chip 33 uses its built-in analog acquisition module to acquire the voltage across the resistor 34. During the acquisition process, the main control chip 33 uses a preset sampling frequency and resolution to ensure the accuracy and real-time nature of the collected data. For example, depending on the response time requirements and sensitivity to voltage changes, a higher sampling frequency (e.g., more than 100 samples per second) can be set while ensuring sufficient resolution (e.g., 12 bits or higher) to accurately measure the voltage changes across the resistor 34. Furthermore, the main control chip 33 performs a range check on the collected voltage value to ensure it is within a reasonable range. If the measured value exceeds the expected range, it may indicate a circuit anomaly. The main control chip 33 can then take appropriate error handling measures, such as logging an error or issuing an error signal to the system.

[0106] S4. When the voltage value exceeds the preset voltage value, the main control chip 33 issues a thermal runaway alarm instruction.

[0107] In specific implementations, the preset voltage value is determined based on the design and experimental testing of the battery pack 1. This preset voltage value is related to various factors, including the characteristics of the battery pack 1, the performance of the gas pressure switch 31, and the parameters of the resistor 34. For example, based on the battery type, size of the battery pack 1, the conduction characteristics of the gas pressure switch 31, and the resistance of the resistor 34, the voltage at which thermal runaway of the battery pack 1 is considered to have occurred can be determined through experimental and theoretical calculations. Therefore, this application does not impose any restrictions on the preset voltage value.

[0108] The thermal runaway alarm method for a battery pack 1 provided in this embodiment utilizes a main control chip 33 to monitor the voltage across a resistor 34, accurately reflecting the on / off state of the gas pressure switch 31 in the form of a voltage signal. This allows for accurate and reliable monitoring of the status of the battery pack 1. Furthermore, by initially setting the gas pressure switch 31 to the off state, misoperation, false alarms, and unnecessary energy consumption can be avoided, ensuring more reliable operation of the entire battery power system under both normal and abnormal conditions.

[0109] In the description of the embodiments of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to a fixed connection, an indirect connection via an intermediate medium, internal communication between two components, or an interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on specific circumstances.

[0110] In the embodiments of the present application, any device or element referred to or implied must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the embodiments of the present application. In the description of the embodiments of the present application, the meaning of "plurality" is two or more, unless otherwise specifically specified.

[0111] The terms "first," "second," "third," "fourth," and so on (if any) in the description and claims of the embodiments of the present application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein, for example, can be implemented in an order other than those illustrated or described herein.

[0112] In addition, the terms "comprises" and "having" and any variations thereof are intended to cover a non-exclusive inclusion. For example, a process, method, system, product or apparatus that includes a series of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, product or apparatus.

[0113] The term "plurality" in this document refers to two or more. The term "and / or" in this document simply describes an association between related objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone.

[0114] It will be understood that the various numerical numbers involved in the embodiments of the present application are merely distinctions for the convenience of description and are not intended to limit the scope of the embodiments of the present application.

[0115] It can be understood that in the embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0116] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present application that follow the general principles of the present application and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0117] It should be understood that the present application is not limited to the exact structure 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 air pressure switch (31), characterized in that: include: Shell (311); a diaphragm assembly (312), at least a portion of the diaphragm assembly (312) being electrically conductive, the diaphragm assembly (312) dividing the inner cavity of the housing (311) into a first chamber (3111) and a second chamber (3112) that are isolated from each other, and a first vent hole (3113) communicating with the first chamber (3111) and the outside of the housing (311) being provided on the housing (311); a connecting terminal (313), there being at least one connecting terminal (313), and the connecting terminal (313) being arranged in the second chamber (3112); The diaphragm assembly (312) is configured to move in response to the air pressure difference between the first chamber (3111) and the second chamber (3112), so that the conductive portion of the diaphragm assembly (312) contacts or separates from the connecting terminal (313).

2. The gas pressure switch (31) according to claim 1, characterized in that There are at least two connecting terminals (313), and at least two of the connecting terminals (313) are spaced apart in the second chamber (3112). The at least two connecting terminals (313) are respectively used to connect to an external circuit. When the diaphragm assembly (312) moves with the pressure difference between the first chamber (3111) and the second chamber (3112), the at least two connecting terminals (313) can contact or separate from the conductive part of the diaphragm assembly (312).

3. The gas pressure switch (31) according to claim 2, characterized in that The diaphragm assembly (312) comprises: a conductive member (3122), wherein the conductive member (3122) is arranged on a side of the diaphragm assembly (312) facing the second chamber (3112), and the diaphragm assembly (312) can be deformed under a preset pressure to drive the conductive member (3122) to move, so as to contact or separate from at least two of the connecting terminals (313).

4. The gas pressure switch (31) according to claim 3, characterized in that The diaphragm assembly (312) further includes: a deformable diaphragm (3121), wherein the deformable diaphragm (3121) is an elastic member, the deformable diaphragm (3121) is connected to the conductive member (3122), and is used to separate the first chamber (3111) and the second chamber (3112), and the deformable diaphragm (3121) is configured to deform in response to the air pressure difference between the first chamber (3111) and the second chamber (3112).

5. The gas pressure switch (31) according to claim 1, characterized in that Also includes: An elastic return member (314), when the diaphragm assembly (312) moves, the diaphragm assembly (312) abuts against the elastic return member (314), and the elastic return member (314) is used to provide a force to the diaphragm assembly (312) toward one side of the first chamber (3111).

6. The gas pressure switch (31) according to claim 5, characterized in that The elastic return member (314) is provided in the first chamber (3111) and / or the second chamber (3112), one end of the elastic return member (314) is connected to the housing (311), and the other end cooperates with the diaphragm assembly (312) to apply a return force opposite to the direction of the air pressure force to the diaphragm assembly (312).

7. The gas pressure switch (31) according to claim 1, characterized in that The housing (311) comprises: a first shell (3114), the first shell (3114) having a first inner cavity (3114a), the diaphragm assembly (312) being provided in the first shell (3114), the diaphragm assembly (312) dividing the first inner cavity (3114a) into a first sub-cavity (3114a1) and a second sub-cavity (3114a2) distributed along a first direction, The first sub-cavity (3114a1) constitutes the first chamber (3111), and the second sub-cavity (3114a2) constitutes part of the second chamber (3112).

8. The gas pressure switch (31) according to claim 7, characterized in that The housing (311) further comprises: a second shell (3115), the first shell (3114) and the second shell (3115) are connected along a first direction, and the second shell (3115) has a second inner cavity (3115a). The second sub-cavity (3114a2) and the second inner cavity (3115a) are interconnected and together constitute the second chamber (3112).

9. The gas pressure switch (31) according to claim 8, characterized in that One end of the first shell (3114) facing the second shell (3115) is formed as an opening (3114b). The first vent hole (3113) is provided on a shell wall at one end of the first shell (3114) opposite to the opening (3114b).

10. The gas pressure switch (31) according to claim 9, characterized in that A communication port (3115b) is provided on a shell wall of the second shell (3115) facing the first shell (3114), and the communication port (3115b) connects the second sub-cavity (3114a2) and the second inner cavity (3115a).

11. The gas pressure switch (31) according to claim 9, characterized in that Part of the structure of the connecting terminal (313) is provided in the second housing (3115), and extends from the opening (3114b) into the second sub-cavity (3114a2).

12. The gas pressure switch (31) according to any one of claims 1 to 11, characterized in that The housing (311) is also provided with a second vent hole (3116) communicating with the second chamber (3112) and the outside of the housing (311).

13. The gas pressure switch (31) according to claim 12, characterized in that Also includes: A breathable membrane (3116a) covers the second vent hole (3116) and / or the first vent hole (3113).

14. The gas pressure switch (31) according to claim 13, characterized in that The volume of the second chamber (3112) is greater than the volume of the first chamber (3111).

15. The gas pressure switch (31) according to claim 12, characterized in that The conductive portion of the diaphragm assembly (312) is configured as a conductive member (3122). When the air pressures in the first chamber (3111) and the second chamber (3112) are balanced, the conductive member (3122) and the connecting terminal (313) are spaced apart.

16. The gas pressure switch (31) according to claim 15, characterized in that The second chamber (3112) is provided with an elastic return member (314). When the air pressures in the first chamber (3111) and the second chamber (3112) are balanced, the distance between the conductive member (3122) and the connecting terminal (313) is X, the elastic coefficient of the elastic return member (314) is K, the area of ​​the surface of the side of the diaphragm assembly (312) facing the second chamber (3112) is S, and when the conductive member (3122) contacts the connecting terminal (313), the air pressure difference between the first chamber (3111) and the second chamber (3112) is , , X, K, S satisfy: .

17. A power distribution module (30), characterized in that: include: a detection circuit, the detection circuit being adapted to be connected to a power source external to the power distribution module (30); The air pressure switch (31) according to any one of claims 1 to 16, arranged in the detection circuit connection, the detection circuit being configured to generate a signal change when the diaphragm assembly (312) of the air pressure switch (31) is connected to or disconnected from the connection terminal; The chip unit is provided in the detection circuit and is used to detect signal changes of the detection circuit to detect whether an abnormality occurs.

18. The power distribution module (30) according to claim 17, characterized in that The chip unit includes: An SBC chip (32) connected to the power supply; A main control chip (33) is connected to the SBC chip (32), and the SBC chip (32) is used to supply power to the main control chip (33); The air pressure switch (31) is provided between the power supply and the SBC chip (32) to control the on-off between the power supply and the SBC chip (32).

19. The power distribution module (30) according to claim 18, characterized in that Also includes: A resistance element (34) is connected in series with the air pressure switch (31) and then connected in parallel to both ends of the power supply. The main control chip (33) is connected in parallel with the resistance element (34) to collect the voltage across both ends of the resistance element (34); The main control chip (33) issues a thermal runaway alarm instruction when the voltage across the two ends of the resistance element (34) is greater than or equal to a preset voltage value.

20. The power distribution module (30) according to claim 19, characterized in that The preset voltage value is 6V-18V.

21. A battery pack (1), characterized in that: include: A box body (10) having a receiving cavity (11); A battery module (20) is disposed in the accommodating cavity (11); The power distribution module (30) according to any one of claims 17 to 20, and / or the air pressure switch (31) according to any one of claims 1 to 16, wherein the first vent hole (3113) of the air pressure switch (31) is in communication with the accommodating cavity (11).

22. The battery pack (1) according to claim 21, characterized in that The accommodating cavity (11) comprises: a battery cavity (111) and a power distribution cavity (112); the battery cavity (111) and the power distribution cavity (112) are communicated with each other; the battery cavity (111) is suitable for arranging the battery module (20); and the power distribution cavity (112) is suitable for arranging the power distribution module (30).

23. A thermal runaway alarm method for a battery pack, characterized in that: The following steps are involved: Confirm that the air pressure switch (31) is conducting; The SBC chip (32) supplies power to the main control chip (33); The main control chip (33) obtains the voltage value across the resistor element (34); When the voltage value exceeds a preset voltage value, the main control chip (33) issues a thermal runaway alarm instruction.

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