A device and control method for suppressing abnormal fires in lithium batteries during civil aviation flights.

Abstract

This invention relates to the field of aviation safety technology, and discloses a suppression device and control method for abnormal lithium battery fires in civil aviation. The device includes an openable, closable box-shaped suppression isolator, which consists of a flame-retardant intermediate layer, a metal partition inner layer, and a plastic outer layer. An integrated detection component monitors temperature, smoke, and characteristic gases. An extinguishing agent release component includes an aerosol extinguishing agent generator and a perfluorohexanone coolant storage tank. The control system performs graded early warning and linkage control based on multi-sensor data regarding thermal runaway intensity and lithium battery capacity. A fire-resistant sealed bag is connected to the isolator via a pressure relief valve to achieve directional emission of harmful gases. Through automatic detection, graded response, two-stage fire extinguishing cooling, and closed-loop feedback regulation, open flames can be quickly extinguished in a confined environment and reignition prevented, while simultaneously avoiding the spread of toxic fumes, thus improving the safety and efficiency of handling high-altitude lithium battery fires.

Description

Technical Field

[0001] This invention relates to the field of aviation safety technology, and in particular to a device and control method for suppressing abnormal fires in lithium batteries during civil aviation. Background Technology

[0002] With the widespread use of lithium-ion battery-containing electronic devices such as smartphones, tablets, laptops, and power banks, the risk of fires caused by lithium-ion batteries during civil aviation transportation has increased significantly. Lithium-ion battery fires are characterized by their sudden onset, intense combustion, high re-ignition rate, and potential release of toxic fumes and jet flames. In the confined cabin environment at 10,000 meters altitude, handling these fires is extremely difficult, seriously threatening the safety of the aircraft and passengers. Currently, standard procedures for responding to lithium-ion battery fires in the cabin mainly rely on flight attendants using water or Class A fire extinguishers for cooling and extinguishing, and using fireproof bags for physical isolation. These methods suffer from delayed response, incomplete handling, and high secondary risks. To improve the automation and intelligence of the response, existing Chinese invention patent CN11883... The 1280A discloses "a safety system and control method for early warning and suppression of thermal disasters of lithium batteries in flight". This technical solution uses an early warning system to monitor temperature and gas change data in the lithium battery compartment online to issue early warnings and links with the fire extinguishing system to extinguish fires, thus achieving active early warning and automatic suppression. However, this solution is only applicable to cargo holds, and its fire extinguishing process is completely open, making personnel susceptible to exposure to high-temperature and toxic environments and air exposure. The fire extinguishing methods for lithium batteries of different capacities are relatively simple, resulting in incomplete fire extinguishing and a high risk of reignition, making it unsuitable for ordinary civil aviation scenarios. Summary of the Invention

[0003] This application discloses a suppression device and control method for abnormal fires in lithium batteries in civil aviation, in order to solve the technical problems of poor environmental adaptability and single fire extinguishing method in related technologies.

[0004] To solve the above problems, the present invention adopts the following technical solution:

[0005] The first aspect of this application provides a suppression device for abnormal fires in lithium batteries during civil aviation operations, installed inside the passenger cabin of a civil aircraft. The device includes a suppression isolator and an integrated detection assembly mounted on the suppression isolator. The suppression isolator is an openable box-shaped structure, including a flame-retardant intermediate layer, a metal partition inner layer, and a plastic outer layer. A feedback module is embedded within the suppression isolator, and an RFID tag reader is externally mounted to identify the capacity of the runaway lithium battery. The integrated detection assembly includes a temperature sensor, a smoke sensor, and a special gas sensor for online monitoring of lithium battery thermal runaway characteristic signals. The suppression isolator also includes a fire extinguishing agent release assembly, comprising a fire extinguishing agent release... The device includes a fire extinguishing agent generator and a coolant storage tank, each connected to a solenoid valve. A fire-resistant sealing bag is installed outside the suppression isolation body, connected to the suppression isolation body via a pressure relief valve. The bag contains a double-layer adsorption and purification module, comprising an outer activated carbon layer and an inner metal mesh layer. The suppression device also includes a control system, which is signal-connected to the integrated detection component, the RFID tag reader, and the fire extinguishing agent release component. It is equipped with a graded alarm and a fire extinguishing agent release controller, based on warning levels and lithium battery capacity logic. The graded alarm is electrically connected to the fire extinguishing agent release controller.

[0006] In a preferred embodiment, the special gas sensor includes a hydrogen fluoride sensor and a carbon monoxide sensor.

[0007] In a preferred embodiment, the feedback module includes a temperature sensor and a pressure sensor, and the feedback module is connected to the control system signal for real-time acquisition of temperature and pressure data within the suppression isolation body.

[0008] In a preferred embodiment, the extinguishing agent generator contains an aerosol extinguishing agent, and the coolant storage tank contains perfluorohexanone, with polyethylene glycol derivatives added as an anticoagulant.

[0009] In a preferred embodiment, the lithium batteries are divided into low-capacity and high-capacity groups based on their capacity. The low-capacity group consists of lithium batteries with a capacity of ≤100Wh, while the high-capacity group consists of lithium batteries with a capacity of 100Wh-160Wh. The warning level classification logic of the control system divides the risk of thermal runaway of the lithium batteries into four-level warning, three-level warning, two-level warning, and one-level warning. The fire extinguishing agent release controller is configured with four-level release rules, three-level release rules, two-level release rules, and one-level release rules corresponding to the warning levels, as well as release rules configured according to the lithium battery capacity. The fire extinguishing agent release rules corresponding to the warning levels have higher priority than the release rules configured according to the lithium battery capacity.

[0010] In a preferred embodiment, an elastic flame-retardant strip is provided along the edge of the opening and closing portion of the suppression isolator, and the elastic flame-retardant strip is made of fluororubber.

[0011] In a preferred embodiment, the integrated detection component is further configured with a cabin zoning early warning unit, which divides the cabin into a seating area, a luggage rack area, and a lavatory area, and calibrates monitoring thresholds for each area separately.

[0012] In a preferred embodiment, the extinguishing agent release assembly is further provided with an emergency activation mechanism, which includes a mechanical pull ring disposed on the side of the suppression isolator, the mechanical pull ring being mechanically connected to the solenoid valve of the extinguishing agent release assembly; the pressure relief valve of the fire-resistant sealing bag is also provided with a manual opening knob.

[0013] The second aspect of this application provides a control method for a suppression device for abnormal fires in lithium batteries in civil aviation, comprising the following steps: S1, continuously collecting temperature, smoke concentration, and special gas concentration data of the target area inside the aircraft through the integrated detection component, and performing interference filtering on the collected data; S2, the control system analyzes the interference-filtered monitoring data based on a preset warning level classification logic, identifies the risk of thermal runaway of the lithium battery, and outputs a graded warning result; S3, if the control system confirms a fire, immediately activates a buzzer alarm, and maintenance personnel place the dangerous lithium battery into the sealed space of the suppression isolator. S4, the extinguishing agent release controller calls the extinguishing agent matching release rule according to the warning level and the capacity of the runaway lithium battery, and controls the extinguishing agent release component to first release the corresponding dose of aerosol extinguishing agent to extinguish the open flame, and then release the corresponding dose of coolant for continuous cooling; at the same time, the harmful gases and extinguishing agent vapors in the suppression isolation body are discharged into the fire-resistant sealed bag through the pressure relief valve; S5, the feedback module in the suppression isolation body collects the temperature and pressure data in the isolation body in real time and feeds it back to the control system. If the temperature does not drop to the safety threshold, the control system controls the extinguishing agent release component to release coolant.

[0014] In a preferred embodiment, the control system warning level judgment in step S2 also incorporates cabin environmental air pressure data: if the integrated detection component detects that the cabin air pressure is below 80 kPa, the temperature warning threshold is lowered by 5°C-8°C to adapt to the characteristic of lithium battery thermal runaway temperature occurring earlier under low air pressure conditions.

[0015] The technical solution adopted in this invention can achieve the following beneficial effects:

[0016] This application provides a suppression device and control method for abnormal lithium battery fires in civil aviation. By setting up an openable, three-layered suppression isolation structure, it achieves rapid containment of the burning battery and effective sealing of the high-temperature, high-pressure environment. Combined with integrated detection components for multi-parameter fusion monitoring of temperature, smoke, and characteristic gases, it can accurately identify anomalies in the early stages of thermal runaway. Utilizing a two-stage release system containing aerosol extinguishing agent and perfluorohexanone coolant, it first chemically interrupts the combustion chain reaction to quickly extinguish the open flame, and then continuously vaporizes and absorbs heat to deeply cool the battery cell and dilute the oxygen concentration, effectively preventing reignition. The control system intelligently adjusts the release strategy based on graded early warning and lithium battery capacity fire extinguishing logic, and achieves closed-loop regulation through a feedback module. Smoke is directed into a fire-resistant sealed bag via a pressure relief valve to avoid contaminating the cabin air. This solves the problems of slow response, poor environmental adaptability, incomplete fire extinguishing, high risk of reignition, and personnel exposure associated with existing technologies, significantly improving the safety, automation level, and reliability of handling lithium battery fires in civil aviation. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an overall structural block diagram of a device for suppressing abnormal fires in lithium batteries during civil aviation, as disclosed in some embodiments of this application.

[0019] Figure 2 This is a schematic diagram of the structure of a suppression isolator in a suppression device for abnormal fires in lithium batteries in civil aviation, as disclosed in some embodiments of this application;

[0020] Figure 3 This is a first-view cross-sectional view of a suppression isolator in a suppression device for abnormal fires in lithium batteries in civil aviation, as disclosed in some embodiments of this application;

[0021] Figure 4 This is a second-view cross-sectional view of a suppression isolator in a suppression device for abnormal fires in lithium batteries in civil aviation, as disclosed in some embodiments of this application;

[0022] Figure 5 This application discloses a schematic diagram of the structure of a fire extinguishing agent release component in a device for suppressing abnormal fires in lithium batteries in civil aviation.

[0023] Figure 6This is a flowchart illustrating the steps of a control method for a device used to suppress abnormal fires in lithium batteries during civil aviation, as disclosed in some embodiments of this application.

[0024] In the picture:

[0025] 1. A device for suppressing abnormal fires in lithium batteries during civil aviation flights;

[0026] 10. Suppression barrier; 11. Integrated detection assembly; 12. Extinguishing agent release assembly; 13. Control system; 14. Fire-resistant sealing bag;

[0027] 100. Flame-retardant intermediate layer; 101. Inner layer of metal partition; 102. Outer layer of plastic; 103. Feedback module; 104. Elastic flame-retardant strip; 105. RFID tag reader; 110. Cabin area warning unit; 120. Emergency activation mechanism; 140. Pressure relief valve; 141. Activated carbon layer; 142. Metal mesh frame layer;

[0028] 1400. Manually turn on the knob. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0030] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0031] With the widespread use of portable electronic devices in civil aviation, lithium-ion battery-containing electronic products such as smartphones, tablets, laptops, and power banks have become potential fire hazards in passenger cabins. Once a lithium battery experiences thermal runaway, it can cause violent combustion, flame ejection, and the release of large amounts of toxic fumes and heat. In the confined environment of a passenger cabin at 10,000 meters altitude, handling such situations is extremely difficult and poses a significant safety threat. Currently, emergency response relies mainly on flight attendants manually identifying the fire and using water-based fire extinguishers or fire bags. This approach suffers from delayed response, incomplete extinguishing, and a high rate of reignition. Furthermore, existing solutions for handling thermal runaway lithium batteries during flight are often only applicable to cargo holds, leaving passenger cabins vulnerable to the risk of personnel exposure to high temperatures, flames, and harmful gases. Especially if the fire is not identified in its early stages, the optimal response time can be missed, leading to escalation and seriously endangering flight safety and passenger lives.

[0032] The following is in conjunction with the appendix Figures 1 to 6 This application provides a detailed description of a device and control method for suppressing abnormal fires in lithium batteries during civil aviation, through specific embodiments and application scenarios.

[0033] Please refer to Figures 1-5 This application provides a device 1 for suppressing abnormal fires in lithium batteries during civil aviation operations. Installed inside a civil aviation cabin, it includes a suppression isolator 10 and an integrated detection assembly 11 mounted on the suppression isolator 10. The suppression isolator 10 is an openable box-shaped structure, including a flame-retardant intermediate layer 100, a metal partition inner layer 101, and a plastic outer layer 102. A feedback module 103 is embedded within the suppression isolator 10, and an RFID tag reader 105 is installed externally to identify the capacity of the runaway lithium battery. The integrated detection assembly 11 includes a temperature sensor, a smoke sensor, and a special gas sensor for online monitoring of lithium battery thermal runaway characteristic signals. A fire extinguishing agent release assembly 12 is also installed within the suppression isolator 10. The device includes a fire extinguishing agent generator and a coolant storage tank, each connected to a solenoid valve. A fire-resistant sealed bag 14 is installed outside the suppression isolation body 10, which is connected to the suppression isolation body 10 through a pressure relief valve 140. A double-layer adsorption purification module is installed inside the bag, including an outer activated carbon layer 141 and an inner metal mesh layer 142. The suppression device 1 for abnormal fires in lithium batteries in civil aviation also includes a control system 13, which is connected to the integrated detection component 11, the RFID tag reader 105 and the fire extinguishing agent release component 12. It is equipped with a graded alarm and a fire extinguishing agent release controller with logic divided according to the warning level and the lithium battery capacity. The graded alarm and the fire extinguishing agent release controller are electrically connected.

[0034] Understandably, the suppression device 1 for abnormal lithium battery fires in civil aviation integrates physical isolation, multi-parameter sensing, intelligent control, chemical fire extinguishing and thermal management, and targeted collection of hazardous products to achieve rapid response and closed-loop handling of abnormal lithium battery fires. The suppression isolation body 10, as the core load-bearing structure, provides mechanical protection and a thermal barrier; its box-shaped, openable design facilitates the rapid placement and sealing of hazardous sources. The integrated detection component 11 is deployed within the device body, which is installed in a specific area of ​​the cabin. It can capture in real time the temperature anomalies, visible smoke, and characteristic decomposition gases released in the early stages of lithium battery thermal runaway, improving detection sensitivity. The fire extinguishing agent release component 12 incorporates high-efficiency fire extinguishing and continuous cooling components, which can work synergistically in enclosed spaces to quickly extinguish open flames and suppress deep thermal runaway reactions. The control system 13, as the central unit, receives data input from the detection system and performs risk assessment and classification. The system responds to the strategy and drives the actuators. The fire-resistant sealing bag 14 establishes a fluid channel with the suppression isolator 10 through the pressure relief valve 140. While maintaining stable internal pressure, it guides high-temperature flue gas and fire extinguishing byproducts into the dedicated fire-resistant sealing bag to prevent pollutants from spreading to the cabin environment. At the same time, the activated carbon layer 141 and the metal mesh layer 142 in the double-layer adsorption purification module inside the fire-resistant sealing bag 14 can adsorb most of the toxic substances released by the runaway lithium battery and evaporated during the fire extinguishing stage in the suppression isolator 10, reducing the contact between personnel and toxic substances after fire extinguishing, and ensuring that toxic substances do not leak out to the greatest extent possible, thus ensuring the safety of personnel in the civil aviation cabin.

[0035] Specifically, when not in use, the fire-resistant sealed bag is folded inside the strip on the suppression insulator 10 for easy storage.

[0036] Specifically, because civil aviation requires passengers to undergo security checks before flight, all portable lithium battery devices inspected during the security check must comply with relevant regulations and 3C certification. Currently available smartphones, tablets, and laptops have built-in power capacities of less than 100Wh due to battery safety standards, classifying them as low-capacity lithium batteries. Furthermore, according to civil aviation regulations, portable power banks are strictly limited to a battery capacity of 160Wh. Power banks with a capacity greater than 100Wh require prior notification from passengers. In this embodiment, these are high-capacity lithium batteries. Therefore, security personnel can directly affix RFID tags to high-capacity power banks during security checks, while other devices are left untagged. This facilitates identification by the RFID tag reader 105 on the suppression isolator 10, allowing for rapid identification of the lithium battery capacity group and subsequent fire suppression logic judgment. Since the reading distance of the RFID tag reader 105 is typically 0.3-0.5 meters, the tag can be read simultaneously when the flight attendant places the lithium battery into the suppression isolator 10.

[0037] Specifically, the aforementioned components are organically linked through electrical signals, fluid pathways, and mechanical structures. For example, when the integrated detection component 11 detects a composite signal in the target area that matches the trend of lithium battery thermal runaway, the control system 13 immediately activates the graded alarm to issue an audible and visual warning, prompting the crew to take intervention measures. After the dangerous lithium battery is manually transferred to the suppression isolator 10 and sealed, the control system 13 automatically starts the extinguishing agent release procedure according to the preset logic. At this time, the solenoid valves at the front end of the extinguishing agent generator and coolant storage tank are opened in a controlled manner, releasing the extinguishing medium sequentially or proportionally. Simultaneously, the pressure and temperature changes inside the device are monitored in real time by the embedded feedback module 103 and transmitted back to the control system 13, forming a closed-loop control. If the system determines that there is still a risk of reignition, a supplementary release mechanism can be triggered. During this process, when the pressure rises due to the expansion of the gas generated by the reaction, the pressure relief valve 140 is automatically opened, guiding the smoke into the fire-resistant sealed bag 14, ensuring that the overall operation is safe and controllable.

[0038] It should be noted that, through the above technical solution, this application realizes an integrated treatment process from fire detection to isolation, suppression, cooling, and pollution control. Due to the use of a multi-layered box-type suppression and isolation body 10 with a flame-retardant intermediate layer 100, a metal partition inner layer 101, and a plastic outer layer 102, the thermal insulation, impact resistance, and flame-retardant capability of the structure are significantly enhanced. It can maintain integrity in high-temperature environments and effectively limit the spread of fire. The flame-retardant intermediate layer 100 is preferably zirconium-containing aluminosilicate needle-punched blanket insulation cotton. A composite detection system integrating temperature, smoke, and special gas sensors improves the accuracy of identifying early signs of lithium battery thermal runaway and reduces the false alarm rate. The combination of a fire extinguishing agent generator and a coolant storage tank enables both rapid suffocation extinguishing and prolonged deep cooling, cutting off the thermal runaway chain reaction path. The control system 13 coordinates alarm and extinguishing actions based on graded early warning logic, improving the intelligence level of the response. The combined use of the fire-resistant sealing bag 14, the pressure relief valve 140, and the double-layer adsorption purification module ensures the safe and directional emission of harmful gases, avoiding secondary pollution. The entire device can be deployed in the existing cabin environment without complex modifications. It is easy to operate, highly automated, and significantly reduces the risk of flight attendants directly contacting hazardous sources, thereby improving the safety and reliability of handling in-flight lithium battery fires.

[0039] Furthermore, special gas sensors include hydrogen fluoride sensors and carbon monoxide sensors.

[0040] Understandably, the special gas sensor is a key component in the integrated detection assembly 11 used to identify the characteristic toxic gases released in the early stages of thermal runaway in lithium batteries. During thermal runaway, the internal electrolyte (such as lithium hexafluorophosphate LiPF6) of a lithium battery reacts with trace amounts of moisture to generate hydrogen fluoride (HF), while the cathode material (such as lithium cobalt oxide, nickel-manganese-cobalt ternary materials, etc.) decomposes at high temperatures, releasing toxic gases such as carbon monoxide (CO). These gases are highly corrosive and toxic, and can usually be detected within seconds to tens of seconds before an open flame appears. Therefore, they can serve as important chemical markers for determining whether a lithium battery has entered the irreversible thermal runaway stage. By configuring dedicated sensors with high selectivity and sensitivity to HF and CO, the system's ability to identify real lithium battery fires can be significantly improved, avoiding misjudging ordinary smoke in civil aviation cabins (such as water vapor, dust, or aerosols generated by food heating) as battery thermal runaway events. Since hydrogen fluoride and carbon monoxide are unique decomposition products of lithium battery material systems, their co-occurrence characteristics are highly specific. Therefore, by introducing these two types of sensors, the system can distinguish lithium battery anomalies from other types of smoke events from a chemical perspective without relying on visual observation, significantly reducing the false alarm rate, improving the overall intelligence level and operational reliability of the device, and thus solving the technical problem of delayed response and improper handling caused by existing cabin fire handling methods that rely on manual judgment.

[0041] Specifically, the suppression isolation body 10 can be arranged in key areas of the cabin (such as under the luggage rack or near the seat back air vents) to form a spatial coverage network. This allows for trend prediction and location alarms based on the abnormal rising trend of HF and CO concentrations in the local air, even if the lithium battery is not immediately placed inside the suppression isolation body 10. The control system 13 performs fusion analysis on multi-channel gas data according to a preset algorithm. When the concentrations of the two gases simultaneously exceed the dynamic threshold and are accompanied by a sudden temperature rise, it is determined to be a high-confidence lithium battery thermal runaway event, triggering subsequent response procedures.

[0042] Specifically, in this embodiment, the hydrogen fluoride sensor uses the EC Sense TB420-EC4-HF smart hydrogen fluoride sensor module, with a detection range of 0-10ppm and a resolution of up to 0.01ppm; the carbon monoxide sensor uses the EC Sense DS4-CO smart carbon monoxide sensor, with a detection range of 0-100ppm and a resolution of 0.1ppm, which meets the requirements of ordinary lithium battery runaway scenarios in civil aviation.

[0043] Furthermore, the feedback module 103 includes a temperature sensor and a pressure sensor. The feedback module 103 is connected to the control system 13 for real-time acquisition of temperature and pressure data within the suppression isolation body 10.

[0044] Specifically, the feedback module 103 includes a temperature sensor and a pressure sensor, which are integrated at key monitoring locations within the internal space of the suppression isolator 10 to dynamically sense the thermodynamic state in a closed environment. The temperature sensor is used to detect real-time temperature changes within the cavity of the suppression isolator 10, while the pressure sensor is used to detect the upward trend of internal gas pressure, suitable for capturing instantaneous pressurization processes caused by battery eruption, electrolyte vaporization, or fire extinguishing agents.

[0045] Optionally, the temperature sensor is configured with multiple measuring points to form a distributed temperature measurement network, located near the battery placement area, the aerosol diffusion path, and the coolant outlet, thereby enabling spatial temperature gradient analysis. The pressure sensor is set in the gas accumulation area at the top or side to facilitate the capture of the maximum pressure peak. The temperature sensor can be a platinum resistance thermometer (Pt100 or Pt1000), a thermocouple, or a digital semiconductor temperature sensor, and can be packaged in a high-temperature resistant and interference-resistant manner, such as a ceramic package or a stainless steel sheath structure. The pressure sensor can be a piezoresistive or capacitive microelectromechanical system (MEMS) sensor, which has good long-term stability and vibration resistance, and is suitable for the complex operating conditions during aircraft flight. The specific model is not limited in this embodiment. The above sensors are arranged on the inner wall of the suppression isolation body near the bottom or middle area, avoiding the direct injection channel to prevent misreading caused by the impact of the extinguishing agent, while effectively reflecting the overall temperature and pressure trend.

[0046] Understandably, the feedback module 103, composed of temperature and pressure sensors, and connected to the control system 13, can continuously acquire thermodynamic state information within the confined space. This solves the problem of rigid response strategies caused by the lack of internal state perception in traditional devices, improves the controllability and thoroughness of the fire suppression process, effectively prevents the risk of reignition, and enhances the overall safety margin.

[0047] Furthermore, the extinguishing agent generator contains an aerosol extinguishing agent, the coolant storage tank contains perfluorohexanone, and polyethylene glycol derivatives are added as anticoagulants.

[0048] Specifically, aerosol fire extinguishing agents are used to quickly extinguish open flames in lithium batteries. Their mechanism of action mainly relies on the synergistic effect of solid particles and gaseous products, releasing a large amount of inert gas and free radical capturing substances in a very short time, interrupting the combustion chain reaction, and achieving a highly efficient and oxygen-free fire extinguishing effect. At the same time, perfluorohexanone, as a clean and environmentally friendly inert gas coolant, has excellent vaporization heat absorption performance and electrical insulation properties. It can rapidly vaporize and absorb a large amount of heat after release, penetrating deep into the battery module for deep cooling, while reducing the local oxygen concentration and forming a continuous inert environment, effectively suppressing the risk of reignition. Furthermore, in order to further improve the reliability of the system in high-altitude and low-temperature environments, this embodiment adds polyethylene glycol derivatives as anti-condensing agents to perfluorohexanone. Polyethylene glycol derivatives have good low-temperature fluidity and chemical stability, which can significantly reduce the crystallization tendency of perfluorohexanone, preventing it from undergoing phase transitions or crystal precipitation during the aircraft's cruise phase, thereby avoiding failures such as pipeline blockage and valve jamming.

[0049] Specifically, the extinguishing agent and coolant are stored in separate sealed chambers and released in stages through solenoid valves: first, the aerosol extinguishing agent generator is triggered to suppress the initial fire; then, the coolant injection program is started based on internal feedback signals to achieve long-term temperature control; the two complement each other in function, with the former focusing on instantaneous fire extinguishing capability and the latter emphasizing continuous thermal management capability, together forming a multi-level protection system that achieves efficient suppression and prevention of reignition of lithium battery thermal runaway fires.

[0050] Furthermore, lithium batteries are divided into low-capacity and high-capacity groups based on their capacity. The low-capacity group consists of lithium batteries with a capacity of ≤100Wh, while the high-capacity group consists of lithium batteries with a capacity of 100Wh-160Wh. The warning level classification logic of the control system 13 divides the risk of thermal runaway of lithium batteries into four-level warning, three-level warning, two-level warning, and one-level warning. The fire extinguishing agent release controller is configured with four-level release rules, three-level release rules, two-level release rules, and one-level release rules corresponding to the warning level, as well as release rules configured according to the lithium battery capacity. The fire extinguishing agent release rules corresponding to the warning level have higher priority than the release rules configured according to the lithium battery capacity.

[0051] Specifically, the four-level warning level classification logic and agent dosage matching rules of the control system 13 are as follows: Level 4 release rules: temperature exceeds 60℃ (the upper limit of lithium battery operating temperature), no smoke or special gases, no release of aerosol fire extinguishing agent, and release of 5% of the total amount of modified perfluorohexanone;

[0052] Level 3 release rules: Temperature exceeds the self-heating temperature of lithium battery, CO ≤ 25 PPM, no release of aerosol fire extinguishing agent, release of 20% of the total amount of modified perfluorohexanone;

[0053] Secondary release rules: If the temperature exceeds the lithium battery valve opening temperature, or HF ≤ 10 PPM and 25 PPM < CO ≤ 100 PPM, 50% of the total aerosol extinguishing agent and 50% of the total modified perfluorohexanone will be released.

[0054] Level 1 Release Rule: If an open flame, high concentration of smoke, or HF > 10 PPM or CO > 100 PPM is detected, release 100% of the total amount of aerosol extinguishing agent and 80% of the total amount of modified perfluorohexanone, and maintain the inert environment for ≥ 30 minutes.

[0055] It should be noted that for lithium batteries of different capacities, low-capacity lithium batteries have relatively low combustion intensity, open flame duration ≤2 minutes, relatively low reignition rate, and low release of toxic gases; high-capacity lithium batteries have relatively high combustion intensity, open flame duration 3-5 minutes, relatively high reignition rate, and are prone to producing explosive fragments; the thermal runaway process of low-capacity and high-capacity lithium batteries is different, therefore it is necessary to formulate specific fire extinguishing rules according to portable lithium batteries of different capacities.

[0056] Specifically, for low-capacity lithium batteries, no aerosol fire extinguishing agent is released, but 30% of modified perfluorohexanone is released; for high-capacity lithium batteries, 50% of aerosol fire extinguishing agent is released, and 80% of modified perfluorohexanone is released.

[0057] It should be noted that the priority of the extinguishing agent release rule corresponding to the warning level is higher than the release rule configured according to the lithium battery type. This means that in actual application, the total amount range of the basic agent is first determined by the four-level release rule. The agent is released according to the initial internal temperature and pressure conditions. After the release under the four-level release rule is completed, the agent is continuously released or replenished according to the lithium battery type release rule. For example, when a high-capacity lithium battery experiences thermal runaway, and its thermal runaway is in the four-level or three-level warning stage, after it is placed in the suppression isolation body 10, the extinguishing agent is first released according to the four-level or three-level release rule. After the extinguishing agent under this rule is released, the extinguishing agent under the high-capacity lithium battery release rule is continuously released to ensure that the lithium battery will not reignite, completely isolate the risk, and improve the utilization rate of the extinguishing agent.

[0058] As can be understood, as mentioned above, high-capacity lithium batteries are tagged with RFID tags during security checks and can be directly identified by the RFID tag reader 105 on the isolation body 10. After identification, the control system matches the release rules for high-capacity lithium batteries; while unidentified lithium batteries are automatically classified as low-capacity lithium batteries, and the control system matches the release rules for low-capacity lithium batteries.

[0059] Understandably, the mapping relationship between the aforementioned warning levels and release rules establishes a "risk level - response intensity" matching mechanism, enabling the system to accurately invoke corresponding response strategies based on the stage of fire development. This avoids overreaction while ensuring safety, improving the intelligence level and resource utilization efficiency of emergency response. At the same time, it provides clear operational guidelines for crew members, allowing them to take corresponding measures such as observation, preparation for isolation, or immediate response based on the warning level. This effectively solves the technical problems of erroneous activation of small risks or delayed response to large risks caused by the uniform response mode in existing technologies.

[0060] Furthermore, an elastic flame-retardant strip 104 is provided along the edge of the opening and closing part of the isolation body 10, and the elastic flame-retardant strip 104 is made of fluororubber.

[0061] Specifically, fluororubber is a high-performance synthetic rubber with excellent high-temperature resistance: long-term operating temperature can reach above 200℃, short-term resistance to 300℃, excellent chemical stability, and good mechanical strength and resilience.

[0062] Understandably, the introduction of an elastic element with high-reliability sealing capability into the dynamic opening and closing structure of the isolation body 10, and the use of the stable performance of fluororubber material under extreme conditions, solves the technical problem that traditional sealing materials are prone to failure in high-temperature and corrosive environments, leading to a decline in sealing performance. This significantly enhances the device's ability to isolate flames, smoke and harmful gases caused by thermal runaway of lithium batteries, ensuring the safety and effectiveness of the air disposal process.

[0063] Furthermore, the integrated detection component 11 is also equipped with a cabin zoning early warning unit 110, which divides the cabin into a seating area, a luggage rack area, and a lavatory area, and calibrates the monitoring thresholds for each area separately.

[0064] Specifically, the cabin, as a special environment with dense crowds and clearly defined spatial divisions within a civil aircraft, requires the installation of the suppression device 1 for abnormal lithium battery fires in civil aviation in the seating area, overhead bins, and lavatory areas. Each area exhibits significantly different environmental parameters during daily use, including temperature and humidity, airflow distribution, frequency of passenger activity, and equipment storage habits. For example, the overhead bins, being in a closed state and frequently used for storing electronic devices, may have higher internal temperatures due to sunlight or self-heating from the equipment. The seating area, where passengers frequently use electronic devices placed in seat pockets or near armrests, poses a risk of localized hotspots. The lavatory area, with its high humidity, short ventilation cycle, and tendency for smoke to accumulate, but typically lacking a high-temperature source, is prone to false alarms or missed alarms if a uniform monitoring threshold is used.

[0065] As an optional implementation, in the luggage rack area, due to the relatively high ambient temperature and the presence of normal heat sources, the alarm threshold of the temperature sensor can be appropriately increased by 2℃-5℃ to avoid false alarms caused by sunlight or equipment standby heat; at the same time, the smoke concentration threshold remains unchanged to ensure that real fires are not missed; in the seating area, considering the frequent operation of electronic devices by passengers, the system can be set with a dynamic response mechanism, so that when multiple adjacent seats are detected to have slight temperature rises in a short period of time, a low-level warning can be activated even if a single threshold is not reached; while in the restroom area, the response threshold of the smoke sensor is reduced and the sensitivity to brief high-concentration smoke pulses is enhanced to quickly detect possible illegal smoking or small appliance fires, while a humidity compensation algorithm is used to eliminate water vapor interference.

[0066] Specifically, when an alarm is triggered in the overhead luggage compartment, the system prioritizes advising flight attendants to move the equipment into the containment barrier 10; when an alarm is triggered in the seating area, the system activates the lighting and voice prompts in that area to guide passengers and flight attendants to safety; and when an alarm is triggered in the lavatory area, the system reminds flight attendants to enter the lavatory area to assess the situation.

[0067] Understandably, this embodiment achieves refined monitoring of abnormal lithium battery fires in civil aviation. Different cabin areas have different environmental characteristics and risk types. If a uniform and fixed monitoring threshold is used, it is difficult to balance sensitivity and anti-interference capabilities in various scenarios, which can easily lead to false alarms or delayed responses. However, by introducing regional early warning units and calibrating the monitoring thresholds for each area, the system can dynamically adjust the judgment criteria according to the actual usage characteristics of different areas, thereby effectively reducing the false alarm rate caused by non-fire factors and improving the accuracy of identifying real fires. Therefore, the technical means provided in this embodiment enhance the environmental adaptability and intelligence level of the integrated detection component 11, reducing unnecessary emergency response burden while ensuring flight safety, and improving the efficiency of cabin crew and the passenger experience.

[0068] Furthermore, the extinguishing agent release assembly 12 is also provided with an emergency activation mechanism 120, which includes a mechanical pull ring located on the side of the suppression isolation body 10. The mechanical pull ring is mechanically connected to the solenoid valve of the extinguishing agent release assembly 12. The pressure relief valve 140 of the fire-resistant sealing bag 14 is also equipped with a manual opening knob 1400.

[0069] Specifically, by setting up a purely mechanical operating device independent of the electronic control system 13, the availability of the system under extreme failure conditions is enhanced. Among them, the emergency start mechanism 120 provides a direct start method that does not rely on electricity and signal transmission when the automatic control system 13 fails, ensuring that the fire extinguishing function can still be activated. The mechanical pull ring is set on the side of the suppression isolator 10 for easy identification and access by the operator. The mechanical pull ring forms a mechanical linkage with the solenoid valve of the fire extinguishing agent release assembly 12 through rigid or flexible transmission components such as steel cables, connecting rods or push rods. When the operator applies a pulling force, it can directly overcome the preload of the spring inside the solenoid valve and force open the valve channel, thereby releasing the aerosol fire extinguishing agent and coolant. The pressure relief valve 140 on the fireproof sealing bag 14 is equipped with a manual opening knob 1400, which allows the operator to actively control the timing of pressure release according to the site conditions, avoiding the risk of structural rupture caused by excessive internal pressure in the isolator due to the failure of the automatic pressure relief logic.

[0070] Understandably, through the above design, this embodiment enables key fire extinguishing and venting actions to be completed manually even in the event of power outages, control unit failures, or other electronic system anomalies. Because of the mechanical pull ring connected to the solenoid valve, the extinguishing agent release can be triggered manually even if the control system 13 fails to send an opening signal. Furthermore, because the pressure relief valve 140 is equipped with a manual opening knob 1400, the accumulated high-temperature smoke can be actively discharged to the fire-resistant sealing bag 14, preventing pressure buildup and secondary hazards. Thus, the problem of the entire fire extinguishing function being paralyzed due to a single point of failure in the electronic system, as seen in existing technologies, is solved, improving the device's adaptability and emergency response success rate in complex aviation environments.

[0071] Please refer to Figure 6 Another embodiment of the present invention also provides a control method for using a suppression device for abnormal fires in lithium batteries in civil aviation as described in the above embodiments, comprising the following steps:

[0072] Step S1: Continuously collect temperature, smoke concentration and special gas concentration data of the target area inside the aircraft through integrated detection components, and perform interference filtering on the collected data;

[0073] Integrated detection components are deployed in key areas of the cabin, such as under seats, inside overhead bins, and near lavatory vents, to monitor changes in environmental conditions in real time. Temperature sensors employ high-precision thermistors or infrared temperature measurement modules with a sampling frequency of at least 1Hz, capable of capturing sudden increases in local temperature. Smoke sensors are photoelectric or ionization detectors used to identify abnormal increases in particulate matter concentration. Special gas sensors include hydrogen fluoride and carbon monoxide detection units, which are highly specific due to their status as typical products of lithium battery electrolyte decomposition. These three types of sensors work together to form a multi-dimensional monitoring network. The collected data is converted from analog to digital before being input into the control system. To avoid false triggering caused by environmental fluctuations (such as temperature fluctuations due to perfume, food vapors, or human activity), the control system incorporates digital filtering algorithms, such as moving average filtering, Kalman filtering, or wavelet denoising, to eliminate instantaneous spikes and periodic interference signals, retaining accurate trend data.

[0074] Step S2: Based on the preset warning level classification logic, the control system analyzes the monitoring data after interference filtering, identifies the risk of lithium battery thermal runaway, and outputs graded warning results.

[0075] Step S3: If the control system confirms a fire, immediately activate the buzzer alarm, and the maintenance personnel place the dangerous lithium battery into the sealed space of the suppression isolator and seal it.

[0076] The buzzer alarm is installed on the top of the device's casing and can be linked to the cabin public address system to issue a voice prompt, ensuring that flight attendants can quickly locate the danger. Upon alarm triggering, flight attendants do not need to immediately extinguish the fire; instead, they move the burning equipment to a containment enclosure located in a designated area of ​​the cabin. This containment enclosure is a box-shaped, openable structure composed of a flame-retardant middle layer, a metal inner layer, and a plastic outer layer, possessing high-temperature resistance and impact resistance. The opening and closing edges are equipped with elastic flame-retardant strips made of fluororubber, which, together with a locking mechanism, achieve a near-sealed seal to prevent flame leakage. This step achieves physical isolation between personnel and the hazardous source, significantly reducing the risk of personnel exposure, while creating a closed working environment for subsequent automatic fire suppression.

[0077] Step S4: The extinguishing agent release controller calls the extinguishing agent matching release rule according to the warning level and the capacity of the runaway lithium battery, and controls the extinguishing agent release component to first release the corresponding dose of aerosol extinguishing agent to extinguish the open flame, and then release the corresponding dose of coolant for continuous cooling; at the same time, it inhibits the harmful gases and extinguishing agent vapors in the isolation body from being discharged into the fire-resistant sealed bag through the pressure relief valve.

[0078] Specifically, the pressure relief valve is located at the top of the suppression isolation body. It automatically opens when the internal pressure exceeds the set limit, specifically 1.5 times the atmospheric pressure, guiding the high-temperature flue gas and chemical vapors into the connected fire-resistant sealed bag. The bag is approximately 800mm×330mm×200mm in size and is made of multi-layer aluminum foil composite material, which can withstand temperatures above 300℃. At the same time, it is equipped with a double-layer adsorption and purification module inside to effectively prevent toxic gases from escaping back into the cabin.

[0079] Step S5: The feedback module inside the isolation chamber collects temperature and pressure data in real time and feeds it back to the control system. If the temperature does not drop to the safety threshold, the control system controls the fire extinguishing agent release component to release coolant.

[0080] The feedback module integrates temperature and pressure sensors, located inside the suppression isolator near the load center, with a sampling interval of 0.5-1 seconds. Data is transmitted to the control system via wired or wireless means. The safety threshold is set at 60°C, indicating that the battery cell has escaped the critical range of thermal runaway. The control system continuously monitors the feedback data. If the temperature is still higher than the threshold after the predetermined cooling cycle, or if a temperature rebound trend occurs, it is determined that the cooling is insufficient or there is an internal short circuit that continues to generate heat. The supplementary cooling program is then initiated, releasing an appropriate amount of perfluorohexanone again. This closed-loop feedback mechanism realizes the dynamic control process for specific fire situations, ensuring a stable and reliable final state and completely eliminating the risk of reignition.

[0081] Understandably, this embodiment implements a lithium battery fire control method integrating multi-source sensing, intelligent classification, sequential execution, and dynamic feedback. Interference filtering improves the quality of raw data and enhances the accuracy of risk identification; graded early warning and matching release rules optimize firefighting resource scheduling, balancing response speed and agent utilization; sealed isolation and directional smoke extraction protect cabin air quality; and a feedback adjustment mechanism establishes a closed-loop control system, ensuring the thoroughness and safety of the response. This method is applicable to various civil aircraft cabin environments and can also be extended to lithium battery safety management in enclosed transportation scenarios such as high-speed rail and subways.

[0082] Furthermore, in step S2, the control system's warning level judgment also incorporates cabin air pressure data. If the integrated detection component detects that the cabin air pressure is below 80 kPa, the temperature warning threshold is lowered by 5°C-8°C to adapt to the characteristic of lithium battery thermal runaway temperature occurring earlier under low air pressure conditions.

[0083] Specifically, when identifying the risk of thermal runaway in lithium batteries, the control system not only relies on data collected by temperature, smoke, and characteristic gas sensors, but also introduces ambient air pressure as a dynamic correction parameter. 80 kPa corresponds to atmospheric pressure at an altitude of approximately 6000 meters, while the cruising altitude of civil aircraft is typically between 9000 and 12000 meters, corresponding to an air pressure range of 26-32 kPa. Therefore, when the cabin air pressure is detected to be below 80 kPa, it indicates that the aircraft has entered the high-altitude flight phase. At this time, the electrolyte evaporation clamps inside the lithium battery and the increased activity of the motors lead to a significant decrease in the thermal runaway initiation temperature compared to sea level conditions. By setting an air pressure-based compensation mechanism, the warning lag caused by a fixed threshold is avoided.

[0084] It should be noted that, in this document, 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. Unless otherwise specified, 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.

[0085] Furthermore, it should be noted that the scope of the methods and apparatus in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

[0086] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A device for suppressing abnormal fires in lithium batteries during civil aviation operations, installed inside the passenger cabin of a civil aircraft, characterized in that, The device includes a suppression isolator and an integrated detection assembly mounted on the suppression isolator. The suppression isolator is an openable box-shaped structure, comprising a flame-retardant intermediate layer, a metal separator inner layer, and a plastic outer layer. A feedback module is embedded within the suppression isolator, and an RFID tag reader is mounted externally to identify the capacity of the runaway lithium battery. The integrated detection assembly includes a temperature sensor, a smoke sensor, and a special gas sensor for online monitoring of lithium battery thermal runaway characteristic signals. The suppression isolation body is also equipped with a fire extinguishing agent release assembly, including a fire extinguishing agent generator and a coolant storage tank, and the fire extinguishing agent generator and the coolant storage tank are respectively connected to a solenoid valve; The suppression and isolation body is provided with a fire-resistant sealing bag, which is connected to the suppression and isolation body through a pressure relief valve. The fire-resistant sealing bag is provided with a double-layer adsorption and purification module inside, including an outer activated carbon layer and an inner metal mesh layer. The suppression device also includes a control system, which is signal-connected to the integrated detection component, the RFID tag reader, and the fire extinguishing agent release component. The control system is equipped with a graded alarm and a fire extinguishing agent release controller with logic divided according to warning level and lithium battery capacity. The graded alarm is electrically connected to the fire extinguishing agent release controller.

2. The suppression device according to claim 1, characterized in that, The special gas sensors include a hydrogen fluoride sensor and a carbon monoxide sensor.

3. The suppression device according to claim 1, characterized in that, The feedback module includes a temperature sensor and a pressure sensor. The feedback module is connected to the control system signal and is used to collect temperature and pressure data within the suppression isolation body in real time.

4. The suppression device according to claim 1, characterized in that, The extinguishing agent generator contains an aerosol extinguishing agent, and the coolant storage tank contains perfluorohexanone, with added polyethylene glycol derivatives as an anticoagulant.

5. The suppression device according to claim 1, characterized in that, Lithium batteries are divided into low-capacity and high-capacity groups based on their capacity. The low-capacity group consists of lithium batteries with a capacity of ≤100Wh, while the high-capacity group consists of lithium batteries with a capacity of 100Wh-160Wh. The warning level classification logic of the control system divides the risk of thermal runaway of lithium batteries into four-level warning, three-level warning, two-level warning, and one-level warning. The fire extinguishing agent release controller is configured with four-level release rules, three-level release rules, two-level release rules, and one-level release rules corresponding to the warning levels, as well as low-capacity release rules and high-capacity release rules configured according to the lithium battery capacity. The fire extinguishing agent release rules corresponding to the warning levels have higher priority than the release rules configured according to the lithium battery capacity.

6. The suppression device according to claim 1, characterized in that, The edge of the opening and closing part of the isolation body is provided with an elastic flame-retardant strip, which is made of fluororubber.

7. The suppression device according to claim 1, characterized in that, The integrated detection component is also equipped with a cabin zoning early warning unit, which divides the cabin into a seating area, a luggage rack area, and a lavatory area, and calibrates monitoring thresholds for each area separately.

8. The suppression device according to claim 1, characterized in that, The extinguishing agent release assembly is also equipped with an emergency activation mechanism, which includes a mechanical pull ring located on the side of the suppression isolator. The mechanical pull ring is mechanically connected to the solenoid valve of the extinguishing agent release assembly. The pressure relief valve of the fire-resistant sealing bag is also equipped with a manual opening knob.

9. A control method for a suppression device for abnormal fires in lithium batteries during civil aviation as described in any one of claims 1-8, characterized in that, Includes the following steps: S1, continuously collect temperature, smoke concentration and special gas concentration data of the target area inside the aircraft through the integrated detection component, and perform interference filtering processing on the collected data; S2, the control system analyzes the monitoring data after interference filtering based on the preset early warning level classification logic, identifies the risk of thermal runaway of lithium battery and outputs graded early warning results; S3, if the control system confirms a fire, immediately activate the buzzer alarm, and the maintenance personnel place the dangerous lithium battery into the sealed space of the suppression isolator and seal it; S4, the extinguishing agent release controller calls the extinguishing agent matching release rule according to the warning level and the capacity of the runaway lithium battery, and controls the extinguishing agent release component to first release the corresponding dose of aerosol extinguishing agent to extinguish the open flame, and then release the corresponding dose of coolant for continuous cooling; at the same time, the harmful gases and extinguishing agent vapors in the suppression isolation body are discharged into the fire-resistant sealing bag through the pressure relief valve; S5, the feedback module inside the isolation chamber collects temperature and pressure data inside the isolation chamber in real time and feeds it back to the control system. If the temperature does not drop to the safety threshold, the control system controls the fire extinguishing agent release component to release coolant.

10. The control method according to claim 9, characterized in that, The control system warning level judgment in step S2 also incorporates cabin air pressure data: if the integrated detection component detects that the cabin air pressure is below 80 kPa, the temperature warning threshold is lowered by 5°C-8°C to adapt to the characteristic of lithium battery thermal runaway temperature occurring earlier under low air pressure conditions.

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