A battery pack fire extinguishing system and control method

Abstract

This application discloses a battery pack fire extinguishing system and control method, relating to the field of automotive technology. The battery pack fire extinguishing system includes a driving component and a nitrogen separation device. The nitrogen separation device is mounted on the battery pack and includes a nitrogen separation assembly, a nitrogen transmission channel, and a nitrogen control switch. The driving component is connected to the nitrogen separation assembly to separate nitrogen from the air. The nitrogen transmission channel is connected at both ends to the nitrogen separation assembly and the cavity of the battery pack, respectively. The nitrogen control switch is located on the nitrogen transmission channel. When the nitrogen control switch is turned on, the nitrogen transmission channel transmits the nitrogen separated by the nitrogen separation assembly into the battery pack. The technical solution of this application enables rapid cooling of the battery cells within the cavity, improving fire extinguishing efficiency, while simultaneously saving water resources.

Description

Technical Field

[0001] This application relates to, but is not limited to, the field of automotive technology, and in particular to a battery pack fire extinguishing system and control method. Background Technology

[0002] Battery packs power electric vehicles, but they are prone to thermal runaway, which can cause spontaneous combustion of the vehicle. Related technologies use large amounts of water to extinguish the fire.

[0003] However, most of the battery packs are located at the bottom of the passenger compartment, so water cannot be sprayed directly into the battery pack. The temperature of the battery cells cannot be reduced quickly, and the cells continue to thermally run away until all the cells thermally run away, causing the entire car to burn. This wastes a lot of water resources and has low fire extinguishing efficiency. Summary of the Invention

[0004] This application provides a battery pack fire extinguishing system and control method, which can quickly reduce the temperature of the battery cells, improve fire extinguishing efficiency, and save water resources.

[0005] To achieve the above objectives, the technical solution of this application embodiment is implemented as follows:

[0006] This application provides a battery pack fire extinguishing system, which includes a driving component and a nitrogen separation device. The nitrogen separation device is disposed on the battery pack and includes a nitrogen separation component, a nitrogen transmission channel, and a nitrogen control switch. The driving component is connected to the nitrogen separation component to separate nitrogen from the air. The two ends of the nitrogen transmission channel are respectively connected to the nitrogen separation component and the cavity of the battery pack. The nitrogen control switch is disposed on the nitrogen transmission channel. When the nitrogen control switch is turned on, the nitrogen transmission channel is used to transmit the nitrogen separated by the nitrogen separation component to the cavity of the battery pack.

[0007] The battery pack fire extinguishing system provided in this application embodiment, because the driving component is connected to the nitrogen separation component, separates nitrogen from the air. Simultaneously, the nitrogen control switch is turned on, and at this time, the nitrogen in the air is transmitted to the cavity of the battery pack through the nitrogen transmission channel. The nitrogen inside the battery pack cavity isolates the battery cells from oxygen, thus enabling the battery cells to cool down rapidly and extinguish the fire quickly, improving fire extinguishing efficiency. Compared to related technologies that use large amounts of water for fire extinguishing, where water cannot reach the inside of the battery pack and the battery cell temperature cannot be reduced quickly, leading to thermal runaway, the technical solution provided in this application, by setting up a nitrogen separation component to separate nitrogen from the air and transmit the separated nitrogen to the cavity of the battery pack through the nitrogen transmission channel, cools the battery cells inside the battery pack and isolates them from oxygen. This rapidly reduces the temperature of the battery cells, improves fire extinguishing efficiency, and saves water resources.

[0008] In one possible implementation provided in this application embodiment, the nitrogen separation assembly includes a cylinder, an adsorbent, and a piston rod. The two ends of the nitrogen transmission channel are respectively connected to the cylinder and the cavity of the battery pack. The adsorbent is disposed in the cylinder and is used to adsorb oxygen under a first pressure range. The driving member is connected to the piston rod to drive the piston rod to slide relative to the cylinder. When the pressure in the cylinder is greater than or equal to the minimum value of the first pressure range, the nitrogen control switch is opened, and the nitrogen in the cylinder is transmitted to the cavity of the battery pack through the nitrogen transmission channel.

[0009] In one possible implementation provided in this application embodiment, the adsorbent's oxygen adsorption performance is positively correlated with the pressure value. When the pressure inside the cylinder is equal to the maximum value of the first pressure range, the nitrogen control switch is turned on, and the nitrogen inside the cylinder is transmitted to the cavity of the battery pack through the nitrogen transmission channel.

[0010] In one possible implementation provided in this application embodiment, the nitrogen separation component includes a cam, the outer wall of the cam abuts against the end of the piston rod away from the cylinder, and a drive member is connected to the cam shaft of the cam to drive the cam to rotate around the cam shaft.

[0011] In one possible implementation provided in this application embodiment, the nitrogen separation device further includes an air transmission channel, an air control switch, an oxygen transmission channel, and an oxygen control switch. The first ends of both the air transmission channel and the oxygen transmission channel are connected to the cylinder body, and the second ends are connected to the outside. The air control switch is set on the air transmission channel, and the oxygen control switch is set on the oxygen transmission channel. The adsorbent is used to release oxygen in the second pressure range. The maximum value of the second pressure range is less than the minimum value of the first pressure range. When the pressure inside the cylinder body is less than or equal to the maximum value of the second pressure range, both the air control switch and the oxygen control switch are opened, and air enters the cylinder body through the air transmission channel, while oxygen is discharged through the oxygen transmission channel.

[0012] In one possible implementation provided in this application embodiment, the oxygen release performance of the adsorbent is negatively correlated with the pressure value. When the pressure inside the cylinder is equal to the minimum value of the second pressure range, both the air control switch and the oxygen control switch are turned on, air enters the cylinder through the air transmission channel, and oxygen is discharged through the oxygen transmission channel.

[0013] In one possible implementation provided in this application embodiment, the nitrogen separation device includes a fan module and a transmission mechanism. The transmission mechanism is connected to the rotating shaft and camshaft of the fan module respectively to drive the fan module to rotate. Along the movement direction of the piston rod, the position of the second end of the oxygen transmission channel is higher than the position of the second end of the air transmission channel.

[0014] In one possible implementation provided in this application embodiment, the battery pack fire extinguishing system includes a position detection device, which is disposed on a piston rod to detect the position of the piston rod within the cylinder.

[0015] In one possible implementation of this application embodiment, the battery pack fire extinguishing system includes a control device, which is electrically connected to a position detection device, a nitrogen control switch, an oxygen control switch, and an air control switch, respectively. The control device controls the opening and closing of the nitrogen control switch, the oxygen control switch, and the air control switch according to the detection result of the position detection device.

[0016] Secondly, the control method for the battery pack fire extinguishing system provided in the embodiments of this application includes:

[0017] In response to the fire suppression requirements of the battery pack, the nitrogen separation component separates nitrogen from the air;

[0018] The nitrogen control switch is turned on, transferring the nitrogen separated by the nitrogen separation component to the cavity of the battery pack.

[0019] The control method for the battery pack fire extinguishing system provided in this application is applicable to the battery pack fire extinguishing system provided in any embodiment of the first aspect, and therefore has the same technical effects. That is, it can quickly reduce the temperature of the battery cells, improve fire extinguishing efficiency, and save water resources.

[0020] In one possible implementation provided in this application embodiment, the nitrogen separation assembly includes a cylinder, an adsorbent, and a piston rod. The two ends of the nitrogen transmission channel are respectively connected to the cylinder and the cavity of the battery pack. The adsorbent is disposed in the cylinder and is used to adsorb oxygen under a first pressure range. The piston rod slides relative to the cylinder.

[0021] The method of controlling the nitrogen control switch to open and transferring the nitrogen separated by the nitrogen separation component to the cavity of the battery pack includes:

[0022] When the pressure inside the cylinder is greater than or equal to the minimum value of the first pressure range, the nitrogen control switch is opened to transfer the nitrogen in the cylinder to the cavity of the battery pack.

[0023] In one possible implementation provided in this application embodiment, the adsorbent's ability to adsorb oxygen is positively correlated with the pressure value;

[0024] When the pressure inside the cylinder is greater than or equal to the minimum value of the first pressure range, the nitrogen control switch is opened to transfer nitrogen from the cylinder to the battery pack cavity. The methods include:

[0025] When the pressure inside the cylinder equals the maximum value of the first pressure range, the nitrogen control switch is opened to transfer the nitrogen inside the cylinder to the cavity of the battery pack.

[0026] In one possible implementation provided in this application embodiment, the nitrogen separation device further includes an air transmission channel, an air control switch, an oxygen transmission channel, and an oxygen control switch. The first ends of both the air transmission channel and the oxygen transmission channel are connected to the cylinder body, and the second ends are connected to the outside. The air control switch is located on the air transmission channel, and the oxygen control switch is located on the oxygen transmission channel. The adsorbent is used to release oxygen in a second pressure range, where the maximum value of the second pressure range is less than the minimum value of the first pressure range. The method includes:

[0027] When the pressure inside the cylinder is less than or equal to the maximum value of the second pressure range, the air control switch and oxygen control switch are opened, air enters the cylinder, and oxygen is discharged from the cylinder.

[0028] In one possible implementation provided in this application embodiment, the adsorbent's ability to release oxygen is negatively correlated with the pressure value;

[0029] When the pressure inside the cylinder is less than or equal to the maximum value of the second pressure range, the air control switch and oxygen control switch are opened, allowing air to enter the cylinder. Methods for venting oxygen from the cylinder include:

[0030] When the pressure inside the cylinder equals the minimum value of the second pressure range, both the air control switch and the oxygen control switch are turned on, allowing air to enter the cylinder and oxygen to be expelled from it. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a battery pack fire suppression system installed in a car, provided in an embodiment of this application.

[0032] Figure 2 This is a schematic diagram of the structure of the nitrogen separation device provided in the embodiments of this application;

[0033] Figure 3 This is a schematic diagram of the internal structure of the nitrogen separation device provided in the embodiments of this application;

[0034] Figure 4 This is a cross-sectional schematic diagram of the nitrogen separation device provided in the embodiments of this application;

[0035] Figure 5 This is one of the partial cross-sectional schematic diagrams of the nitrogen separation device provided in the embodiments of this application;

[0036] Figure 6 This is a second cross-sectional schematic diagram of the nitrogen separation device provided in the embodiments of this application;

[0037] Figure 7 This is the third cross-sectional schematic diagram of the nitrogen separation device provided in the embodiments of this application;

[0038] Figure 8Fourth cross-sectional schematic diagram of the nitrogen separation device provided in the embodiments of this application;

[0039] Figure 9 Fifth cross-sectional schematic diagram of the nitrogen separation device provided in the embodiments of this application;

[0040] Figure 10 Sixth schematic cross-sectional view of the nitrogen separation device provided in the embodiments of this application;

[0041] Figure 11 This is a partial structural schematic diagram of a nitrogen separation device provided in the embodiments of this application;

[0042] Figure 12 One of the flowcharts for the control method of the battery pack fire extinguishing system provided in the embodiments of this application;

[0043] Figure 13 A second flowchart illustrating the control method of the battery pack fire extinguishing system provided in this application embodiment;

[0044] Figure 14 The third flowchart of the control method for the battery pack fire extinguishing system provided in the embodiments of this application;

[0045] Figure 15 Flowchart four of the control methods for the battery pack fire extinguishing system provided in the embodiments of this application;

[0046] Figure 16 The fifth flowchart is a control method for a battery pack fire extinguishing system provided in the embodiments of this application.

[0047] Figure Labels

[0048] 1-Automobile; 11-Battery pack; 2-Battery pack fire extinguishing system; 21-Drive component; 211-Motor; 212-High voltage power supply; 22-Nitrogen separation device; 221-Nitrogen separation assembly; 2211-Cylinder block; 2212-Adsorbent; 2213-Piston rod; 2214-Cam; 222-Nitrogen transmission channel; 223-Air transmission channel; 224-Oxygen transmission channel; 225-Fan module; 226-Transmission mechanism; 227-Position detection device; 228-Control device. Detailed Implementation

[0049] It should be noted that, unless otherwise specified, the embodiments and technical features in the embodiments of this application can be combined with each other, and the detailed descriptions in the specific implementation should be understood as explanations of the purpose of this application and should not be regarded as undue limitations on this application.

[0050] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the specific technical solutions of this application will be further described in detail below with reference to the accompanying drawings of the embodiments of this application. The following embodiments are used to illustrate this application, but are not intended to limit the scope of this application.

[0051] In the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more.

[0052] Furthermore, in the embodiments of this application, directional terms such as "upper," "lower," "left," and "right" are defined relative to the positions in which the components are schematically placed in the accompanying drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and can change accordingly depending on the position of the components in the accompanying drawings.

[0053] In the embodiments of this application, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium.

[0054] In embodiments of this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0055] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0056] Please refer to Figure 1This application provides a vehicle 1. It should be noted that the vehicle 1 mentioned in this application can refer to large vehicles, small vehicles, and special vehicles, etc. For example, according to the vehicle type, the vehicle 1 in this application can refer to a sedan, an off-road vehicle, a multi-purpose vehicle (MPV), or other vehicle types.

[0057] The battery pack 11 is one of the most important parts of the electric vehicle 1. The battery pack 11 mainly consists of battery cells, insulation layers, cooling systems, battery management systems, and fireproof housings. The battery cells are the core of providing power, but when the electric vehicle 1 experiences thermal runaway, causing the vehicle 1 to spontaneously combust, since most of the battery pack 11 is located at the bottom of the passenger compartment of the vehicle 1, water cannot be directly sprayed into the cavity of the battery pack 11, and the temperature of the battery cells cannot be reduced quickly. The battery cells continue to experience thermal runaway until all the battery cells have experienced thermal runaway, causing the entire vehicle 1 to burn out.

[0058] Therefore, please refer to Figure 1 , Figure 2 and Figure 3 This application provides a battery pack fire extinguishing system 2, which includes a driving component 21 and a nitrogen separation device 22. The nitrogen separation device 22 is disposed on the battery pack 11 and includes a nitrogen separation component 221, a nitrogen transmission channel 222, and a nitrogen control switch. The driving component 21 is connected to the nitrogen separation component 221 to separate nitrogen from the air. The two ends of the nitrogen transmission channel 222 are respectively connected to the nitrogen separation component 221 and the cavity of the battery pack 11. The nitrogen control switch is disposed on the nitrogen transmission channel 222. When the nitrogen control switch is turned on, the nitrogen transmission channel 222 is used to transmit the nitrogen separated by the nitrogen separation component 221 to the cavity of the battery pack 11.

[0059] The battery pack fire extinguishing system 2 provided in this application embodiment is connected to the nitrogen separation component 221. The nitrogen separation component 221 separates nitrogen from the air. At the same time, the nitrogen control switch is turned on. At this time, the nitrogen in the air is transmitted to the cavity of the battery pack 11 through the nitrogen transmission channel 222. The nitrogen in the cavity of the battery pack 11 isolates the battery cells in the cavity from oxygen. In this way, the battery cells can be cooled down quickly and the fire can be extinguished quickly, thus improving the fire extinguishing efficiency.

[0060] It should be noted that the drive component 21 can be a combination of the high-voltage power supply 212 and the motor 211 of the electric vehicle 1. The high-voltage power supply 212 drives the motor 211 to operate, and the operation of the motor 211 drives the nitrogen separation component 221 to separate nitrogen from the air. Alternatively, the drive component 211 can be a backup low-power high-voltage power supply 212 installed on the vehicle 1. When the low-power high-voltage power supply 212 receives a fire extinguishing signal, it drives the motor 211 to operate, and the operation of the motor 211 drives the nitrogen separation component 221 to separate nitrogen from the air. Of course, the drive component 21 can also be of other types of structures, and this application embodiment does not limit the type of drive component 21.

[0061] Furthermore, the principle applied by the nitrogen separation component 221 in separating nitrogen from the air can be the pressure swing adsorption nitrogen generation principle; it can also be the cryogenic air separation nitrogen generation principle; or it can also be the membrane air separation nitrogen generation principle. This application embodiment does not limit the principle applied by the nitrogen separation component 221 in separating air. In one possible implementation method provided in this application embodiment, the principle applied by the nitrogen separation component 221 in separating air is the pressure swing adsorption nitrogen generation principle.

[0062] The pressure swing adsorption (PSA) nitrogen generation principle utilizes carbon molecular sieves as the adsorbent. Carbon molecular sieves exhibit a significant difference in adsorption rates for oxygen and nitrogen; in a short time, the adsorption rate for oxygen is much higher than that for nitrogen. This characteristic is used to achieve oxygen-nitrogen separation. The oxygen adsorption capacity of the carbon molecular sieve decreases with decreasing pressure, and desorption (release of oxygen from the carbon molecular sieve) is completed when the pressure is lowered. The nitrogen-oxygen adsorption separation pressure is typically selected between 0.6 and 0.8 MPa, while the commonly used operating pressure of the air conditioning compressor (high-pressure component) in automobile 1 is 1.3 to 1.7 MPa. Therefore, a miniaturized device can be implemented in automobile 1 to extinguish thermal runaway in electric vehicle 1.

[0063] Specifically, please refer to Figure 1 , Figure 4 , Figure 5 and Figure 6 The nitrogen separation assembly 221 includes a cylinder 2211, an adsorbent 2212, and a piston rod 2213. The two ends of the nitrogen transmission channel 222 are connected to the cylinder 2211 and the cavity of the battery pack 11, respectively. The adsorbent 2212 is disposed inside the cylinder 2211 and is used to adsorb oxygen under a first pressure range. The driving component 21 is connected to the piston rod 2213 to drive the piston rod 2213 to slide relative to the cylinder 2211. When the pressure inside the cylinder 2211 is greater than or equal to the minimum value of the first pressure range, the nitrogen control switch is opened, and the nitrogen in the cylinder 2211 is transmitted to the cavity of the battery pack 11 through the nitrogen transmission channel 222. The adsorbent 2212 is the carbon molecular sieve described in the above embodiment.

[0064] It should be noted that the pressure inside cylinder 2211 changes with the position of piston rod 2213 inside cylinder 2211, but the pressure range inside cylinder 2211 should overlap with the first pressure range at least. This ensures that the pressure inside cylinder 2211 is greater than or equal to the minimum value of the first pressure range. At this time, adsorbent 2212 adsorbs oxygen in the first pressure range. When the nitrogen control switch is turned on, the nitrogen in cylinder 2211 is transferred to the cavity of battery pack 11 through nitrogen transmission channel 222 to isolate the battery cells inside the cavity of battery pack 11 from oxygen, thereby achieving the purpose of cooling and fire extinguishing.

[0065] Based on this, the oxygen adsorption performance of adsorbent 2212 is positively correlated with the pressure value, that is, the higher the pressure value, the stronger the oxygen adsorption performance of adsorbent 2212. In this embodiment, the oxygen adsorption performance of adsorbent 2212 is positively correlated with the pressure value. When the pressure in cylinder 2211 is equal to the maximum value of the first pressure range, the nitrogen control switch is turned on, and the nitrogen in cylinder 2211 is transmitted to the cavity of battery pack 11 through nitrogen transmission channel 222.

[0066] Compared to when the pressure inside cylinder 2211 equals the minimum value of the first pressure range, the oxygen control switch is turned on, and the nitrogen in cylinder 2211 is transferred to the cavity of battery pack 11 through nitrogen transmission channel 222. When the pressure inside cylinder 2211 equals the maximum value of the first pressure range, the nitrogen control switch is turned on, and the nitrogen transmitted through nitrogen transmission channel 222 is purer and can more effectively isolate the battery cells in the cavity of battery pack 11 from oxygen, achieving the purpose of cooling and extinguishing fire.

[0067] Please refer to Figure 1 , Figure 7 , Figure 8 and Figure 9 In addition to being directly connected to the piston rod 2213 to drive the piston rod 2213 to slide relative to the cylinder 2211 and change the pressure inside the cylinder 2211 to separate nitrogen from the air, the driving member 21 can also indirectly drive the piston rod 2213 to slide relative to the cylinder 2211, changing the pressure inside the cylinder 2211 to separate nitrogen from the air. For example, the nitrogen separation assembly 221 includes a cam 2214, the outer wall of which abuts against the end of the piston rod 2213 away from the cylinder 2211. The driving member 21 is connected to the camshaft of the cam 2214 to drive the cam 2214 to rotate around the camshaft, thereby driving the piston rod 2213 to slide relative to the cylinder 2211 and change the pressure inside the cylinder 2211.

[0068] Specifically, the cam 2214 may include a convex portion and a concave portion. When the end of the piston rod 2213 away from the cylinder body 2211 abuts against the concave portion of the cam 2214, the pressure inside the cylinder body 2211 is small. When the drive member 21 drives the cam shaft, causing the cam 2214 to rotate from the concave portion to the convex portion, the end of the piston rod 2213 away from the cylinder body 2211 moves toward one side of the cylinder body 2211, and the pressure inside the cylinder body 2211 increases. When the pressure inside the cylinder body 2211 is greater than or equal to the minimum value of the first pressure range, the nitrogen control switch is opened, and the nitrogen in the cylinder body 2211 is transmitted to the cavity of the battery pack 11 through the nitrogen transmission channel 222.

[0069] Here, the nitrogen control switch can be located at one end of the nitrogen transmission channel 222 near the cylinder 2211. When the nitrogen control switch is turned on, the end of the nitrogen transmission channel 222 near the cylinder 2211 is open, and nitrogen from the cylinder 2211 can enter the nitrogen transmission channel 222 and then be transmitted to the cavity of the battery pack 11. Alternatively, the nitrogen control switch can be located at the end of the nitrogen transmission channel 222 away from the cylinder 2211 and near the battery pack 11. When the nitrogen control switch is turned on, the end of the nitrogen transmission channel 222 away from the cylinder 2211 and near the battery pack 11 is open, and nitrogen from the nitrogen transmission channel 222 can be transmitted to the cavity of the battery pack 11. In addition, the nitrogen control switch can be located at any position between the two ends of the nitrogen transmission channel 222. This embodiment of the application does not limit the location of the nitrogen control switch.

[0070] Based on this, the embodiments of this application do not limit the type of nitrogen control switch. The nitrogen control switch can be a plate-like structure. When the nitrogen control switch is closed, the plate-like structure abuts against at least one end of the nitrogen transmission channel 222, so that at least one end of the nitrogen transmission channel 222 is closed. The nitrogen control switch can also be a clamping structure. When the nitrogen switch is closed, the clamping structure clamps onto the outer wall of the nitrogen transmission channel 222 to block the path of the nitrogen transmission channel 222. Of course, the nitrogen control switch can also be other structures.

[0071] Because nitrogen from the air is transferred to the cavity of the battery pack 11 through nitrogen transmission channel 222, the nitrogen content in the air is low and cannot continuously extinguish the fire in the cavity of the battery pack 11. Therefore, the nitrogen separation device also includes an air transmission channel 223, an air control switch, an oxygen transmission channel 224, and an oxygen control switch. The first ends of both the air transmission channel 223 and the oxygen transmission channel 224 are connected to the cylinder 2211, and the second ends are connected to the outside. The air control switch is located on the air transmission channel 223, and the oxygen control switch is located on the oxygen transmission channel 224. The adsorbent 2212 is used to release oxygen in the second pressure range. The maximum value of the second pressure range is less than the minimum value of the first pressure range. When the pressure inside the cylinder 2211 is less than or equal to the maximum value of the second pressure range, both the air control switch and the oxygen control switch are opened, allowing air to enter the cylinder 2211 through the air transmission channel 223 and oxygen to exit through the oxygen transmission channel 224. In this way, fresh air can continuously enter the cylinder 2211, further separating nitrogen from the air to achieve a continuous fire extinguishing effect.

[0072] Since the oxygen release performance of adsorbent 2212 is negatively correlated with the pressure value, in order to enable adsorbent 2212 to completely release the adsorbed oxygen, when the pressure inside cylinder 2211 is equal to the minimum value of the second pressure range, both the air control switch and the oxygen control switch are turned on. Air enters cylinder 2211 through air transmission channel 223, and oxygen is discharged through oxygen transmission channel 224. In this way, nitrogen separation device 22 can continue to separate the air entering cylinder 2211 through air transmission channel 223, and the separated nitrogen is transmitted to the cavity of battery pack 11 through nitrogen transmission channel 222.

[0073] Here, the air control switch can be located at the first end of the air transmission channel 223 near the cylinder 2211. When the air control switch is turned on, the end of the air transmission channel 223 near the cylinder 2211 is open, and outside air can enter the air transmission channel 223 and then the cylinder 2211. The air control switch can also be located at the second end of the air transmission channel 223 that is connected to the outside. When the air control switch is turned on, the second end of the air transmission channel 223 is open, and outside air can enter the cylinder 2211. In addition, the air control switch can also be located at any position between the two ends of the air transmission channel 223. The embodiments of this application do not limit the position of the air control switch.

[0074] Based on this, the embodiments of this application do not limit the type of air control switch. The air control switch can be a plate-like structure. When the air control switch is closed, the plate-like structure abuts against at least one end of the first end and the second end of the air transmission channel 223, so that at least one end of the air transmission channel 223 is closed. The air control switch can also be a clamping structure. When the air control switch is closed, the clamping structure clamps onto the outer wall of the air transmission channel 223 to block the path of the air transmission channel 223. Of course, the air control switch can also be other structures.

[0075] Similarly, the oxygen control switch can be located at the first end of the oxygen transmission channel 224 near the cylinder 2211. When the oxygen control switch is turned on, the end of the oxygen transmission channel 224 near the cylinder 2211 is open, and oxygen in the cylinder 2211 can enter the oxygen transmission channel 224 and then be discharged to the outside. The oxygen control switch can also be located at the second end of the oxygen transmission channel 224 that is connected to the outside. When the oxygen control switch is turned on, the second end of the oxygen transmission channel 224 is open, and oxygen in the oxygen transmission channel 224 can be discharged to the outside through the second end. In addition, the oxygen control switch can also be located at any position between the two ends of the oxygen transmission channel 224. The embodiments of this application do not limit the position of the oxygen control switch.

[0076] Based on this, the embodiments of this application do not limit the type of oxygen control switch. The oxygen control switch can be a plate-like structure. When the oxygen control switch is closed, the plate-like structure abuts against at least one end of the first end and the second end of the oxygen transmission channel 224, so that at least one end of the oxygen transmission channel 224 is in a closed state. The oxygen control switch can also be a clamping structure. When the oxygen control switch is closed, the clamping structure clamps onto the outer wall of the oxygen transmission channel 224 to block the path of the oxygen transmission channel 224. Of course, the oxygen control switch can also be other structures.

[0077] Please refer to Figure 1 , Figure 4 , Figure 10 and Figure 11To increase the rate at which outside air enters the cylinder 2211 and the rate at which oxygen released by the adsorbent 2212 exits the cylinder 2211, in one embodiment of this application, the nitrogen separation device further includes a fan module 225 and a transmission mechanism 226. The transmission mechanism 226 is connected to the rotating shaft of the fan module 225 and the shaft of the cam 2214, respectively, to drive the fan module 225 to rotate, causing air to flow at the second ends of the air transmission channel 223 and the oxygen transmission channel 224. Furthermore, along the direction of movement of the piston rod 2213, the position of the second end of the oxygen transmission channel 224 is higher than the position of the second end of the air transmission channel 223. This arrangement, analogous to an aircraft wing structure, increases the flow rate of gas above the second end of the oxygen transmission channel 224, reduces the pressure, and causes oxygen to be drawn out of the cylinder 2211, accelerating the rate of oxygen exiting the cylinder 2211 and the rate of air entering the cylinder 2211.

[0078] Please refer to this. Figure 1 , Figure 2 and Figure 3 It should be further noted that the transmission mechanism 226 can be a transmission shaft type, which drives the fan module 225 to rotate by setting several transmission shafts; the transmission mechanism 226 can also be a gear type, which drives the fan module 225 to rotate by setting several gears to mesh; the transmission mechanism 226 can also be a belt drive type. This application embodiment does not limit the type of transmission mechanism 226, as long as it satisfies the requirement that the camshaft drives the fan module 225 to rotate through the transmission mechanism 226.

[0079] To obtain the real-time position of the piston rod 2213 within the cylinder 2211, and thus the pressure within the cylinder 2211 and the current state of the nitrogen separation device 22, in one possible implementation provided in this application, the battery pack fire extinguishing system 2 includes a position detection device 227. The position detection device 227 is disposed on the piston rod 2213 to detect the position of the piston rod 2213 within the cylinder 2211. Since sensors have advantages such as strong adaptability to harsh environments, impact resistance, high stability, and high reliability, they can also be disposed on the cam 2214 to detect the position of the cam 2214. For example, the position detection device 227 is a position sensor. Of course, the position detection device 227 can also be other types of devices; this embodiment of the application does not limit this.

[0080] Based on this, in order to facilitate the opening and closing of the air control switch, oxygen control switch and nitrogen control switch according to the pressure of cylinder 2211, in one possible implementation method provided in this application embodiment, the battery pack fire extinguishing system 2 includes a control device 228. The control device 228 is electrically connected to the position detection device 227, the nitrogen control switch, the oxygen control switch and the air control switch respectively. The control device 228 controls the opening and closing of the nitrogen control switch, the oxygen control switch and the air control switch according to the detection result of the position detection device 227.

[0081] Of course, the control device 228 may include a controller and a control panel. The controller is electrically connected to the position detection device 227, the nitrogen control switch, the oxygen control switch, and the air control switch, respectively. The control panel is electrically connected to the controller. The user can control the opening and closing of the nitrogen control switch, the oxygen control switch, and the air control switch by operating the control panel according to the detection structure of the position detection device 227. For example, the control panel may be a touch screen control panel, but it may also be other types of control panels. This application embodiment does not limit this.

[0082] In addition, please refer to Figure 1 , Figure 3 and Figure 12 This application also provides a control method for a battery pack fire suppression system, which includes steps S1 to S2, specifically:

[0083] Step S1: In response to the fire extinguishing requirement of battery pack 11, nitrogen separation component 221 separates nitrogen from the air;

[0084] Step S2: Control the nitrogen control switch to open, and transfer the nitrogen separated by the nitrogen separation component 221 to the cavity of the battery pack 11.

[0085] This allows the battery cells to cool down quickly, extinguish the fire rapidly, and improve fire extinguishing efficiency.

[0086] Secondly, in response to the fire extinguishing needs of the battery pack 11, such as when the temperature of the battery pack 11 rises to a predetermined temperature, the nitrogen separation component 221 separates nitrogen from the air; or, when the smoke concentration inside the cavity of the battery pack 11 rises to a predetermined concentration, the nitrogen separation component 221 separates nitrogen from the air; the embodiments of this application do not limit the specific factors that respond to the fire extinguishing needs of the battery pack 11.

[0087] Further, please refer to Figure 1 , Figure 3 and Figure 13The nitrogen separation assembly 221 includes a cylinder 2211, an adsorbent 2212, and a piston rod 2213. The two ends of the nitrogen transmission channel 222 are connected to the cylinder 2211 and the battery pack 11, respectively. The adsorbent 2212 is disposed inside the cylinder 2211 and is used to adsorb oxygen under a first pressure range. The piston rod 2213 slides relative to the cylinder 2211. Step S2 controls the nitrogen control switch to open, transmitting the nitrogen separated by the nitrogen separation assembly 221 to the cavity of the battery pack 11. Specifically:

[0088] Step S21: When the pressure inside the cylinder 2211 is greater than or equal to the minimum value of the first pressure range, the nitrogen control switch is opened to transfer the nitrogen inside the cylinder 2211 to the cavity of the battery pack 11.

[0089] Furthermore, please refer to Figure 1 , Figure 3 and Figure 14 The oxygen adsorption capacity of adsorbent 2212 is positively correlated with the pressure value. Step S21, when the pressure inside cylinder 2211 is greater than or equal to the minimum value of the first pressure range, controls the nitrogen control switch to open, transferring the nitrogen inside cylinder 2211 to the cavity of battery pack 11. Specifically:

[0090] Step S211: When the pressure inside cylinder 2211 is equal to the maximum value of the first pressure range, the nitrogen control switch is opened to transfer the nitrogen inside cylinder 2211 to the cavity of battery pack 11.

[0091] In some other embodiments provided in this application, please refer to Figure 1 , Figure 3 and Figure 15 The nitrogen separation device also includes an air transmission channel 223, an air control switch, an oxygen transmission channel 224, and an oxygen control switch. The first ends of both the air transmission channel 223 and the oxygen transmission channel 224 are connected to the cylinder 2211, and the second ends are connected to the outside. The air control switch is located on the air transmission channel 223, and the oxygen control switch is located on the oxygen transmission channel 224. The adsorbent 2212 is used to release oxygen in the second pressure range. The maximum value of the second pressure range is less than the minimum value of the first pressure range. The control method of the battery pack fire extinguishing system 2 also includes step S3, specifically:

[0092] Step S3: When the pressure inside cylinder 2211 is less than or equal to the maximum value of the second pressure range, control the air control switch and oxygen control switch to open, air enters cylinder 2211, and oxygen inside cylinder 2211 is discharged.

[0093] Further, please refer to Figure 1 , Figure 3 and Figure 16 The ability of adsorbent 2212 to release oxygen is negatively correlated with the pressure value. In step S3, when the pressure inside cylinder 2211 is less than or equal to the maximum value of the second pressure range, the air control switch and oxygen control switch are opened, air enters cylinder 2211, and oxygen is discharged from cylinder 2211. This includes step S31: When the pressure inside cylinder 2211 is equal to the minimum value of the second pressure range, both the air control switch and oxygen control switch are opened, air enters cylinder 2211, and oxygen is discharged from cylinder 2211.

[0094] Specifically, in one specific embodiment provided in this application, the initial state of the nitrogen separation component 221 is referenced to... Figure 5 At this time, the air control switch, nitrogen control switch, and oxygen control switch are all in the off state;

[0095] When the driving component 21 triggers the oxygen separation assembly to start working, the cam 2214 shaft rotates clockwise, referring to... Figure 6 During this process, the air control switch, nitrogen control switch, and oxygen control switch remain in the closed state. The piston rod 2213 slides relative to the cylinder 2211, compressing the air inside the cylinder 2211. Oxygen in the air begins to be adsorbed into the adsorbent 2212. The process continues until... Figure 7 In this state, the air is compressed to its minimum volume until it moves to... Figure 8 Before the condition was reached, the cylinder block 2211 was under pressure and a large amount of oxygen was adsorbed.

[0096] exist Figure 8 At this critical moment, the nitrogen control switch is turned on. With cylinder 2211 under high pressure, the nitrogen inside cylinder 2211 is rapidly discharged through nitrogen transmission channel 222 into the thermally runaway battery pack 11 for fire suppression, until the system reaches its critical state. Figure 9 Before the fire starts, the nitrogen control switch remains open, and the nitrogen in cylinder 2211 is discharged into the thermally runaway battery pack 11 through nitrogen transmission channel 222 for fire suppression. Alternatively, the nitrogen control switch can be closed based on the position sensor when the cam 2214 has traveled three-quarters of its stroke, to prevent excessive pressure reduction, oxygen release, and mixing with the nitrogen, which would affect the fire suppression effect.

[0097] exist Figure 9 At this state, the air control switch and oxygen control switch are open, while the nitrogen control switch remains closed, and operation continues until... Figure 10 In this state, the pressure inside cylinder 2211 decreases, the oxygen adsorbed by adsorbent 2212 is released, fresh air enters cylinder 2211 through air transmission channel 223, and the oxygen in cylinder 2211 is discharged to the atmosphere through oxygen transmission channel 224.

[0098] Until it runs to Figure 5 The system returns to its initial state, with the air control switch, oxygen control switch, and nitrogen control switch all in the off state. This cycle repeats to extinguish the fire in the battery pack 11 chamber.

[0099] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A battery pack fire extinguishing system, characterized in that, include: Drive components; A nitrogen separation device is provided, which is installed on a battery pack. The nitrogen separation device includes a nitrogen separation component, a nitrogen transmission channel, and a nitrogen control switch. A driving component is connected to the nitrogen separation component to separate nitrogen from the air. The two ends of the nitrogen transmission channel are respectively connected to the nitrogen separation component and the cavity of the battery pack. The nitrogen control switch is installed on the nitrogen transmission channel. When the nitrogen control switch is turned on, the nitrogen transmission channel is used to transmit the nitrogen separated by the nitrogen separation component to the cavity of the battery pack. The nitrogen separation assembly includes a cylinder, an adsorbent, and a piston rod. The two ends of the nitrogen transmission channel are respectively connected to the cylinder and the cavity of the battery pack. The adsorbent is disposed in the cylinder and is used to adsorb oxygen under a first pressure range. The driving member is connected to the piston rod to drive the piston rod to slide relative to the cylinder. When the pressure in the cylinder is greater than or equal to the minimum value of the first pressure range, the nitrogen control switch is turned on, and the nitrogen in the cylinder is transmitted to the cavity of the battery pack through the nitrogen transmission channel. The nitrogen separation assembly includes a cam, the outer wall of which abuts against the end of the piston rod away from the cylinder, and the drive member is connected to the camshaft of the cam to drive the cam to rotate around the camshaft.

2. The battery pack fire extinguishing system according to claim 1, characterized in that, The adsorbent's ability to adsorb oxygen is positively correlated with the pressure value. When the pressure inside the cylinder is equal to the maximum value of the first pressure range, the nitrogen control switch is turned on, and the nitrogen inside the cylinder is transmitted to the cavity of the battery pack through the nitrogen transmission channel.

3. The battery pack fire extinguishing system according to claim 1, characterized in that, The nitrogen separation device further includes an air transmission channel, an air control switch, an oxygen transmission channel, and an oxygen control switch. The first ends of both the air transmission channel and the oxygen transmission channel are connected to the cylinder, and the second ends are connected to the outside. The air control switch and the oxygen control switch are located on the air transmission channel. The adsorbent is used to release oxygen in a second pressure range. The maximum value of the second pressure range is less than the minimum value of the first pressure range. When the pressure inside the cylinder is less than or equal to the maximum value of the second pressure range, both the air control switch and the oxygen control switch are opened, allowing air to enter the cylinder through the air transmission channel and oxygen to be discharged through the oxygen transmission channel.

4. The battery pack fire extinguishing system according to claim 3, characterized in that, The oxygen release performance of the adsorbent is negatively correlated with the pressure value. When the pressure inside the cylinder is equal to the minimum value of the second pressure range, both the air control switch and the oxygen control switch are turned on, the air enters the cylinder through the air transmission channel, and the oxygen is discharged through the oxygen transmission channel.

5. The battery pack fire extinguishing system according to claim 4, characterized in that, The nitrogen separation device includes a fan module and a transmission mechanism. The transmission mechanism is connected to the rotating shaft of the fan module and the camshaft respectively to drive the fan module to rotate. Along the movement direction of the piston rod, the position of the second end of the transmission channel is higher than the position of the second end of the air transmission channel.

6. The battery pack fire extinguishing system according to claim 1, characterized in that, It includes a position detection device, which is disposed on the piston rod to detect the position of the piston rod within the cylinder.

7. The battery pack fire extinguishing system according to claim 6, characterized in that, The device includes a control unit, which is electrically connected to the position detection device, the nitrogen control switch, the oxygen control switch, and the air control switch, respectively. The control unit controls the opening and closing of the nitrogen control switch, the oxygen control switch, and the air control switch based on the detection result of the position detection device.

8. A control method for a battery pack system according to any one of claims 1 to 7, characterized in that, include: In response to the fire suppression requirements of the battery pack, the nitrogen separation component separates nitrogen from the air; The nitrogen control switch is turned on, and the nitrogen separated by the nitrogen separation component is transferred to the cavity of the battery pack.

9. The control method according to claim 8, characterized in that, The nitrogen separation assembly includes a cylinder, an adsorbent, and a piston rod. The two ends of the nitrogen transmission channel are respectively connected to the cylinder and the cavity of the battery pack. The adsorbent is disposed in the cylinder and is used to adsorb oxygen under a first pressure range. The piston rod slides relative to the cylinder. A method for controlling the nitrogen control switch to open and transferring the nitrogen separated by the nitrogen separation component to the cavity of the battery pack includes: When the pressure inside the cylinder is greater than or equal to the minimum value of the first pressure range, the nitrogen control switch is opened to transfer the nitrogen in the cylinder to the cavity of the battery pack.

10. The control method according to claim 9, characterized in that, The adsorbent's ability to adsorb oxygen is positively correlated with the pressure value; When the pressure inside the cylinder is greater than or equal to the minimum value of the first pressure range, the method of controlling the nitrogen control switch to open and transferring nitrogen from the cylinder to the cavity of the battery pack includes: When the pressure inside the cylinder is equal to the maximum value of the first pressure range, the nitrogen discharge control is opened to transfer the nitrogen inside the cylinder to the cavity of the battery pack.

11. The control method according to claim 9, characterized in that, The nitrogen separation device further includes an air transmission channel, an air control switch, an oxygen transmission channel, and an oxygen control switch. The first ends of both the air transmission channel and the oxygen transmission channel are connected to the cylinder body, and the second ends are connected to the outside. The air control switch is located on the air transmission channel, and the oxygen control switch is located on the oxygen transmission channel. The adsorbent is used to release oxygen in a second pressure range, where the maximum value of the second pressure range is less than the minimum value of the first pressure range. The method includes: When the pressure inside the cylinder is less than or equal to the maximum value of the second pressure range, the air control switch and the oxygen control switch are opened, air enters the cylinder, and oxygen is discharged from the cylinder.

12. The control method according to claim 11, characterized in that, The ability of the adsorbent to release oxygen is negatively correlated with the pressure value; When the pressure inside the cylinder is less than or equal to the maximum value of the second pressure range, the air control switch and the oxygen control switch are opened, air enters the cylinder, and the method for venting oxygen from the cylinder includes: When the pressure inside the cylinder is equal to the minimum value of the second pressure range, both the air control switch and the oxygen control switch are turned on, allowing air to enter the cylinder and oxygen to be discharged from the cylinder.

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