Fuel cell active explosion suppression method and system based on membrane health state early warning

Abstract

The invention discloses a fuel cell active explosion suppression method and system based on membrane health state early warning. The method comprises the following steps: receiving proton exchange membrane health state parameters monitored by an online electrochemical impedance spectroscopy diagnosis system; determining a risk level based on the parameters and a preset threshold; when the risk level is a dangerous level, an emergency explosion suppression linkage control sequence is automatically triggered, and the sequence firstly sends an instruction to an electrical safety subsystem to cut off a fuel cell stack main circuit and discharge energy to eliminate an ignition source; and then an instruction is sent to the explosion suppressant storage and injection subsystem, a high-speed electromagnetic valve is started, an explosion suppressant is injected into a cathode air flow path of the fuel cell stack, and an explosion suppression atmosphere is established. Predictive early warning and active protection are deeply fused, the safety normal form is fundamentally innovated from'fire extinguishing after leakage 'to'explosion suppression before damage', and the problem of active explosion suppression of hydrogen and oxygen intermingling is effectively solved.

Description

Technical Field

[0001] This application relates to the field of fuel cell safety technology, and in particular to a method and system for active explosion suppression of fuel cells based on membrane health status early warning. Background Technology

[0002] The commercialization of proton exchange membrane fuel cells has always been limited by their most fatal internal safety hazard—"hydrogen-oxygen crosstalk." When the proton exchange membrane suffers microscopic damage due to chemical degradation or mechanical stress, hydrogen and oxygen gases mix, creating an explosive atmosphere inside the fuel cell stack. This atmosphere can trigger a catastrophic deflagration upon contact with a catalyst.

[0003] The inventors recognized that existing technologies for preventing hydrogen-oxygen cross-contamination have fundamental logical flaws: the system is passive, the response is delayed, and it lacks foresight. The core issue lies in the deep separation between the two major systems of safety protection and health diagnosis. Specifically, this manifests as follows:

[0004] 1. Security protection is based on post-event awareness and cannot achieve pre-event prevention.

[0005] Current mainstream solutions rely on installing hydrogen concentration sensors in hydrogen pipelines or fuel cell stack compartments. This approach is essentially "leak detection" rather than "risk warning." The sensors only trigger an alarm after hydrogen has penetrated the damaged membrane and leaked into the external gas space. At this point, the membrane inside the fuel cell stack has already ruptured, an explosive atmosphere has formed, and the system is at the critical point of an accident. This consequence-based protection mode is destined to always lag behind the occurrence of risks, unable to intervene in the early stages of safety hazards, and fundamentally loses the ability to prevent deflagration accidents.

[0006] 2. The security system is isolated and disconnected from early warning capabilities.

[0007] Existing fire protection solutions are mostly standalone systems with single functions, creating significant technical barriers compared to front-end technologies capable of early diagnosis (such as online electrochemical impedance spectroscopy). Online EIS, through continuous monitoring of the proton exchange membrane's health status, can predictively assess the risk of membrane damage, making it the ideal "sentinel" for initiating active protection. However, due to a lack of deeply integrated design and interfaces, advanced warning signals cannot be seamlessly and rapidly translated into precise protective actions. This results in the current safety system only being able to provide passive "post-accident remediation" after an accident, unable to utilize existing warning information to automatically and proactively implement explosion suppression measures before the risk reaches a critical threshold, thus failing to achieve a paradigm shift towards "prevention." Summary of the Invention

[0008] This application provides a method and system for active explosion suppression of fuel cells based on membrane health status early warning, aiming to solve the problem that existing technologies cannot actively suppress explosions before the risk of hydrogen-oxygen cross-contamination occurs due to delayed protection timing and disconnection from the early warning system.

[0009] Firstly, a method for active explosion suppression of fuel cells based on membrane health status early warning is provided, including:

[0010] Receive health status parameters of the proton exchange membrane in the fuel cell stack from the online electrochemical impedance spectroscopy diagnostic system;

[0011] Based on the health status parameters and preset thresholds, the current risk level is determined;

[0012] If the risk level is hazardous, the emergency explosion suppression linkage control sequence will be automatically triggered and executed, including:

[0013] Send a command to the electrical safety subsystem to disconnect the main circuit of the fuel cell stack and release energy;

[0014] A command is sent to the explosion suppressant storage and injection subsystem to open the high-speed solenoid valve and inject the explosion suppressant into the cathode air flow path of the fuel cell stack.

[0015] Optionally, the above scheme also includes, after the explosion suppression linkage control sequence is executed, putting the fuel cell stack into a safety latching state, which can only be restarted after manual reset.

[0016] Optionally, in the above scheme, when executing the linkage control sequence, the main circuit is first cut off and the discharge energy is released, and then the explosion suppressant is injected.

[0017] Optionally, in the above scheme, the explosion suppressant is a clean explosion suppressant that does not damage the proton exchange membrane.

[0018] Optionally, in the above scheme, determining the current risk level based on the health status parameters and a preset threshold specifically includes:

[0019] Note level: When the health status parameter is lower than the first threshold, log the information and send a maintenance reminder;

[0020] Warning level: When the health status parameter is less than the second threshold, or the remaining lifetime is less than the first time threshold, a command is sent to the fuel cell controller (FCU) to limit the maximum output power of the fuel cell stack to a preset level;

[0021] Hazard Level: When the health status parameter is less than the third threshold, or the remaining lifespan is less than the second time threshold, or the electrochemical impedance spectroscopy characteristic parameter undergoes a sudden change that exceeds the preset range, the emergency explosion suppression linkage control sequence will be immediately triggered and executed.

[0022] Secondly, a fuel cell active explosion suppression system based on membrane health status early warning is provided, including:

[0023] An online electrochemical impedance spectroscopy diagnostic system is used to continuously monitor the health status of the proton exchange membrane in a fuel cell stack and output health status parameters and remaining lifetime parameters.

[0024] A safety linkage controller, communicatively connected to the online electrochemical impedance spectroscopy diagnostic system, is used to receive the health status and remaining lifetime parameters and make decisions based on a preset risk level threshold. This includes: receiving health status parameters of the proton exchange membrane of the fuel cell stack continuously monitored by the online electrochemical impedance spectroscopy diagnostic system; determining the current risk level based on the health status parameters and the preset threshold; and automatically triggering and executing an emergency explosion suppression linkage control sequence if the risk level is dangerous. The emergency explosion suppression linkage control sequence includes: sending a command to the electrical safety subsystem to cut off the main circuit of the fuel cell stack and release energy; and sending a command to the explosion suppressant storage and injection subsystem to open the high-speed solenoid valve and inject the explosion suppressant into the cathode air path of the fuel cell stack.

[0025] The explosion suppressant storage and injection subsystem is communicatively connected to the safety linkage controller and is used to inject the explosion suppressant into the cathode air flow path of the fuel cell stack in response to the instructions of the safety linkage controller.

[0026] The electrical safety subsystem is communicatively connected to the safety linkage controller and is used to respond to the instructions of the safety linkage controller to cut off the main circuit of the fuel cell stack and release energy.

[0027] Optionally, in the above scheme, the explosion suppressant storage and injection subsystem includes:

[0028] A dedicated explosion suppressant storage tank is used to store liquid explosion suppressant, which is a clean explosion suppressant that does not damage the proton exchange membrane;

[0029] A high-speed solenoid valve, the inlet of which is connected to the outlet of the dedicated explosion suppressant storage tank via a pipeline;

[0030] A fine atomizing nozzle is connected to the outlet of the high-speed solenoid valve and is installed in the cathode air inlet pipe of the fuel cell stack.

[0031] Optionally, in the above scheme, the internal structure of the dedicated explosion suppressant storage tank adopts a gas-liquid separation design.

[0032] Optionally, in the above scheme, the electrical safety subsystem includes:

[0033] A main circuit fast circuit breaker is connected in series on the main output bus of the fuel cell stack to disconnect the main circuit of the fuel cell stack.

[0034] An active energy discharge circuit is connected in parallel with the output terminal of the fuel cell stack via a switching element to consume the electrical energy stored inside the stack.

[0035] Optionally, in the above scheme, the safety linkage controller is configured to execute the following linkage sequence: first control the operation of the electrical safety subsystem, and then control the operation of the explosion suppressant storage and injection subsystem.

[0036] Compared with the prior art, this application has at least the following beneficial effects:

[0037] Based on further analysis and research of existing technical problems, this application recognizes that existing technologies suffer from the problem of being unable to proactively suppress explosions before the risk of hydrogen-oxygen crosstalk occurs due to delayed protection timing and disconnection from early warning systems. By deeply coupling the very early membrane health warning (EIS) with the explosion suppression actuator, a safety closed loop of "prediction-decision-protection" is constructed. Following the millisecond-level precise timing control of "eliminating the ignition source first, and then establishing the explosion suppression atmosphere," a fundamental protective effect is achieved by proactively establishing an explosion suppression environment in key areas inside the fuel cell stack at the initial stage of hydrogen-oxygen crosstalk caused by membrane damage, thereby curbing the risk of deflagration in its infancy.

[0038] This application also has at least the following technical effects:

[0039] 1. A fundamental transformation in the safety system: It has achieved a paradigm shift from "fire suppression after leakage" to "explosion suppression before damage", curbing the most fatal safety hazard of hydrogen-oxygen cross-contamination in its infancy and providing crucial safety assurance for the commercialization of fuel cells.

[0040] 2. Seamless integration of early warning and protection: Through deep integration with the online EIS diagnostic system, safety protection actions are based on accurate and forward-looking membrane health status assessment, achieving a perfect combination of "intelligent early warning" and "precise protection", solving the problems of "ineffective" or "delayed response" in traditional fire protection systems.

[0041] 3. Scientific and Breakthrough Aspects of Knock Suppressant Selection: The successful application of fluorinated ketone formulations such as perfluorohexanone to the specific scenario of fuel cell knock suppression overcomes the technical bias held by those skilled in the art due to their poor performance in lithium battery fire suppression. The unique advantages of this type of formulation in terms of gas-phase knock suppression mechanism and material compatibility were clarified, providing the optimal agent selection for solving the problem of internal deflagration in fuel cells.

[0042] 4. High reliability and coordination of system response: The millisecond-level linkage control timing design ensures the strict sequence and extremely high execution speed of the two key actions of "eliminating ignition sources" and "establishing explosion suppression atmosphere", forming a synergistic multiplier effect of "electrical safety" and "chemical explosion suppression", which greatly improves the probability of successful protection.

[0043] 5. Achieving both economic benefits and availability: It avoids catastrophic damage to core components of the fuel cell stack caused by hydrogen-oxygen crossfire, saving high replacement costs. The explosion suppressant used is clean and residue-free, and the dosage is small, which prevents disasters while maximizing asset protection. Even if the protection is triggered, only resetting and replenishing the explosion suppressant is required, rather than replacing the entire fuel cell stack. Attached Figure Description

[0044] Figure 1 This is a flowchart illustrating an active explosion suppression method for fuel cells based on membrane health status early warning, provided as an embodiment of this application.

[0045] Figure 2 This is a block diagram of the module architecture of an active explosion suppression system for fuel cells based on membrane health status early warning, provided as an embodiment of this application. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0047] In the description of this application: unless otherwise stated, the terms "first," "second," "third," etc., are intended to distinguish the objects they refer to and do not have any special meaning in terms of technical connotation (e.g., they should not be construed as an emphasis on importance or order). Expressions such as "comprising," "including," and "having" also mean "not limited to" (certain units, components, materials, steps, etc.).

[0048] Based on the shortcomings and existing technical biases in the aforementioned technical background, the purpose of this application is to provide a novel active explosion suppression system and method for fuel cells, aiming to fundamentally solve the active protection problem of hydrogen-oxygen crosstalk. The specific objectives of the invention are as follows:

[0049] 1. Achieve a closed loop from "early warning" to "protection": Provide a system and method that can seamlessly integrate with online EIS diagnostic systems. Based on the predictive judgment of proton exchange membrane health status (SOH), it automatically and proactively triggers protective actions when the risk reaches a critical threshold, forming a complete safety closed loop.

[0050] 2. Achieve precise explosion suppression: By injecting a small amount of highly efficient explosion suppressant into the cathode air flow path, an explosion suppression atmosphere is established in the key areas inside the fuel cell stack before the hydrogen-oxygen mixture encounters an ignition source, preventing deflagration from occurring, rather than extinguishing the fire afterward.

[0051] 3. Solve the problem of selecting explosion suppressant: Select and verify a special explosion suppressant that is non-toxic, non-corrosive, residue-free, and non-conductive to core materials such as proton exchange membranes and platinum catalysts, to ensure that the explosion suppression action itself will not cause secondary damage to the fuel cell stack.

[0052] 4. Overcoming technical bias: Clearly demonstrate that although fluorinated ketone cleaners such as perfluorohexanone have limited effectiveness in extinguishing deep-seated fires such as those in lithium batteries, their gas-phase explosion suppression mechanism and excellent material compatibility make them particularly suitable for suppressing hydrogen-oxygen deflagration inside fuel cells, providing a new technical approach for this field.

[0053] 5. Improve system response speed and reliability: Design millisecond-level linkage control timing to coordinate the injection of explosion suppressant with electrical safety measures such as safe power-off of fuel cell stack and energy release, ensuring that protective actions are rapid, reliable and orderly.

[0054] In some embodiments, a method for active explosion suppression of fuel cells based on membrane health status early warning is provided, including:

[0055] Receive health status parameters of the proton exchange membrane in the fuel cell stack from the online electrochemical impedance spectroscopy diagnostic system;

[0056] Based on the health status parameters and preset thresholds, the current risk level is determined;

[0057] If the risk level is hazardous, the emergency explosion suppression linkage control sequence will be automatically triggered and executed, including:

[0058] Send a command to the electrical safety subsystem to disconnect the main circuit of the fuel cell stack and release energy;

[0059] A command is sent to the explosion suppressant storage and injection subsystem to open the high-speed solenoid valve and inject the explosion suppressant into the cathode air flow path of the fuel cell stack.

[0060] In some embodiments, a fuel cell active explosion suppression method based on membrane health status early warning is provided. This method is executed by a safety linkage controller, and its core lies in constructing an automated safety closed loop of "prediction-decision-protection". The method includes:

[0061] Receive health status parameters (e.g., state of health (SOH) and remaining lifetime (RUL) of the fuel cell stack proton exchange membrane from the online electrochemical impedance spectroscopy diagnostic system.

[0062] Based on the health status parameters and preset thresholds, the current risk level is determined;

[0063] If the risk level is dangerous, the emergency explosion suppression linkage control sequence will be automatically triggered and executed.

[0064] Crucially, the emergency explosion suppression linkage control sequence follows the fundamental safety logic of "eliminating the ignition source first, then establishing the explosion suppression atmosphere," ensuring that the risk of ignition is minimized to the greatest extent possible when the explosion suppressant is injected. This sequence specifically includes:

[0065] First, an instruction is sent to the electrical safety subsystem to cut off the main circuit of the fuel cell stack at a speed of microseconds, and simultaneously activate the active energy discharge circuit, aiming to completely eliminate potential ignition sources caused by electrical energy inside the stack.

[0066] Subsequently, after confirming that electrical safety actions have been initiated, a command is sent to the explosion suppressant storage and injection subsystem to open the high-speed solenoid valve, atomizing the liquid explosion suppressant (preferably perfluorohexanone) and precisely injecting it into the cathode airflow path of the fuel cell stack. The explosion suppressant rapidly diffuses with the airflow to the membrane electrode area inside the stack, establishing a non-flammable safety barrier in advance in areas where hydrogen-oxygen mixtures may exist through a combination of physical dilution and chemical inhibition.

[0067] In this embodiment, when executing the linkage control sequence, the main circuit is first cut off and the discharge energy is released, and then the explosion suppressant is injected.

[0068] Through the aforementioned orderly and rapid coordinated control, this method achieves a seamless connection between risk prediction of membrane health status and proactive protective actions, thereby enabling intervention before hydrogen-oxygen cross-contamination leads to deflagration, and realizing a fundamental transformation from post-event remediation to pre-event prevention.

[0069] In some embodiments, after the explosion suppression linkage control sequence is completed, the fuel cell stack is put into a safety latch state, which can only be restarted after manual reset.

[0070] In some embodiments, to ensure the absolute safety of the system after the explosion suppression action is triggered and to prevent secondary risks caused by blind restarting due to unresolved faults, the method further includes a safety state management process: after the explosion suppression linkage control sequence is executed, the safety linkage controller issues a state latch command to put the fuel cell stack into a safety latch state. In this state, the main circuit of the fuel cell stack remains disconnected, and the system refuses to respond to any automatic or remote start requests. The latch state can only be released and the fuel cell stack allowed to restart after a manual reset operation is performed by professional personnel on-site to confirm that the potential hazard has been eliminated.

[0071] In some embodiments, the explosion suppressant is a clean explosion suppressant that does not damage the proton exchange membrane. In some embodiments, the explosion suppressant may be perfluorohexanone or a mixture of perfluorohexanone and an inert gas.

[0072] Regarding the selection of explosion suppressants, this application addresses the specific requirements for internal protection of fuel cell stacks, overcoming the inherent defects and technical biases of traditional fire extinguishing agents. In traditional solutions: while fine water mist / water-based fire extinguishing agents offer good cooling effects, their conductive properties can cause short circuits in the stack, and moisture may impact and dilute the membrane electrode assembly, causing secondary damage; while ABC / BC type dry powder fire extinguishing agents have strong extinguishing capabilities, their strong corrosiveness and difficult-to-remove residues can lead to the complete scrapping of the entire valuable fuel cell stack; and some clean gas fire extinguishing agents, such as traditional halon alternatives, lack sufficient verification of compatibility with membrane electrode materials.

[0073] Crucially, those skilled in the art, based on their experience of "poor performance" in extinguishing deep-seated solid fires such as those involving ternary lithium batteries, are prone to developing a technical bias that "perfluorohexanone is not applicable to this field." This application, however, recognizes that the essence of suppressing explosions in fuel cell hydrogen-oxygen interlocking is to inhibit gas-phase deflagration, not to extinguish deep-seated solid fires. Perfluorohexanone possesses excellent gas-phase explosion suppression mechanisms, superior electrical insulation and material compatibility, and can rapidly evaporate without residue, perfectly meeting the unique need to establish a pre-explosion-suppressing atmosphere within a precision fuel cell stack. Therefore, this application explicitly selects perfluorohexanone or its mixture with an inert gas as a dedicated explosion suppressant. This not only scientifically solves the selection problem but also breaks through the cognitive barriers that have long constrained the development of this field.

[0074] Perfluorohexanone is a liquid at room temperature, making it easy to store and precisely spray. It is non-conductive and non-corrosive, and after effective explosion suppression, it rapidly vaporizes and evaporates without leaving any residue. This ensures that the explosion suppression action does not cause secondary damage to core components of the fuel cell stack, such as the proton exchange membrane and platinum catalyst. Crucially, perfluorohexanone's superior gas-phase explosion suppression efficiency, through a dual mechanism of chemically interrupting the chain reaction and physically diluting the oxygen concentration, effectively suppresses the potentially explosive hydrogen-oxygen atmosphere that may form in the cathode flow path. This overcomes the technical bias held by those skilled in the art regarding its poor performance in extinguishing deep solid fires in lithium batteries, providing a basis for its application in the novel scenario of fuel cell gas-phase explosion suppression.

[0075] In some embodiments, determining the current risk level based on the health status parameters and a preset threshold specifically includes:

[0076] Note level: When the health status parameter is lower than the first threshold, log the information and send a maintenance reminder;

[0077] Warning level: When the health status parameter is less than the second threshold, or the remaining lifetime is less than the first time threshold, a command is sent to the fuel cell controller (FCU) to limit the maximum output power of the fuel cell stack to a preset level;

[0078] Hazard Level: When the health status parameter is less than the third threshold, or the remaining lifespan is less than the second time threshold, or the electrochemical impedance spectroscopy characteristic parameter undergoes a sudden change that exceeds the preset range, the emergency explosion suppression linkage control sequence will be immediately triggered and executed.

[0079] In some embodiments, this application achieves progressive and refined control over membrane degradation risk by setting multiple risk levels, thereby ensuring system availability while ensuring safety. The specific determination mechanism is as follows:

[0080] Note level: When the health status parameter is less than the first threshold (e.g., SOH < 90%), the system determines that the membrane has initial signs of degradation. At this time, the system logs and sends a maintenance reminder to prompt preventive checks, while the system continues to operate normally.

[0081] Warning Level: When the health status parameter is less than the second threshold (e.g., SOH < 80%), or the remaining lifetime is less than the first time threshold (e.g., RUL < 100 hours), the system determines that the risk of membrane rupture has increased significantly. To reduce operating stress, slow down the degradation process, and buy time for remediation, a command is sent to the fuel cell controller (FCU) to limit the maximum output power of the fuel cell stack to a preset level (e.g., 80% of the rated power).

[0082] Hazard Level: When the health status parameter is less than the third threshold (e.g., SOH < 70%), or the remaining lifetime is less than the second time threshold (e.g., RUL < 24 hours), or the electrochemical impedance spectroscopy characteristic parameter undergoes a sudden change exceeding the preset range, the system determines that the membrane is on the verge of failure, and the risk of hydrogen-oxygen crosstalk is imminent. At this time, the emergency explosion suppression linkage control sequence is immediately triggered and executed, initiating the highest level of active safety protection.

[0083] In this embodiment, the "preset range" of the hazard level is not a fixed value, but a dynamic or static threshold determined based on one or more of the following factors:

[0084] Based on historical statistical data: The preset range can be determined by long-term collection and statistical analysis of impedance parameter data of the same type of fuel cell stack during normal aging. For example, this range can be set to 3 to 5 times the average rate of change under normal aging rate, or set outside the mean of historical data ± 3 times the standard deviation. When the parameter change exceeds this statistical boundary, it is judged as an abnormal mutation.

[0085] The preset range is related to the physical failure threshold: it can be determined by linking the abrupt change in electrochemical impedance to the critical state of actual hydrogen-oxygen crosstalk in the membrane through bench testing. For example, experiments have shown that when the ohmic resistance increases by more than 10% within 24 hours, the probability of membrane failure exceeds 90%. Therefore, the "preset range" can be defined as "a change rate exceeding 10% within 24 hours".

[0086] Model-based prediction: The preset range can be predictively set based on a fuel cell degradation model. The system predicts the normal evolution trajectory of parameters in real time based on the current operating state and initial performance. When the actual measured value deviates significantly from the predicted trajectory (e.g., deviation exceeds 15%), it is determined to be "out of preset range".

[0087] The execution entity in this embodiment is the safety linkage controller. The core decision-making mechanism of this application is the hierarchical risk assessment and millisecond-level linkage control algorithm embedded in the safety linkage controller. The controller parses the data packets sent by the EIS system through the CAN bus in real time and classifies the risk level according to SOH and RUL, as shown in Table 1.

[0088]

[0089] When the risk level is Level 3, the controller executes the following irreversible emergency sequence. This sequence is triggered by a hardware interrupt, ensuring the highest priority.

[0090] T0 (Trigger Time): The controller confirms the Level 3 status.

[0091] T0+<1ms: A signal is sent through the digital output port to disconnect the main circuit fast circuit breaker.

[0092] T0+1ms: A signal is sent to close the switch of the active energy discharge circuit and begin energy discharge.

[0093] T0+5ms: After confirming that the electrical action has been performed, the high-speed solenoid valve is opened. The solenoid valve remains open for a preset time T_inject (e.g., 2.0 seconds) to inject a precise dose of the detonator.

[0094] Continuous monitoring: The controller continuously monitors the stack voltage until it is confirmed that the voltage is below the 36V safety threshold.

[0095] Action completed: Sends a confirmation message to the host computer that "the explosion suppression action has been completed" and enters the safety latch state, waiting for manual reset.

[0096] In some embodiments, a fuel cell active explosion suppression system based on membrane health status early warning is provided, comprising:

[0097] An online electrochemical impedance spectroscopy diagnostic system is used to continuously monitor the health status of the proton exchange membrane in a fuel cell stack and output health status parameters and remaining lifetime parameters.

[0098] A safety linkage controller, communicatively connected to the online electrochemical impedance spectroscopy diagnostic system, is used to receive the health status and remaining lifetime parameters and make decisions based on a preset risk level threshold. This includes: receiving health status parameters of the proton exchange membrane of the fuel cell stack continuously monitored by the online electrochemical impedance spectroscopy diagnostic system; determining the current risk level based on the health status parameters and the preset threshold; and automatically triggering and executing an emergency explosion suppression linkage control sequence if the risk level is dangerous. The emergency explosion suppression linkage control sequence includes: sending a command to the electrical safety subsystem to cut off the main circuit of the fuel cell stack and release energy; and sending a command to the explosion suppressant storage and injection subsystem to open the high-speed solenoid valve and inject the explosion suppressant into the cathode air path of the fuel cell stack.

[0099] The explosion suppressant storage and injection subsystem is communicatively connected to the safety linkage controller and is used to inject the explosion suppressant into the cathode air flow path of the fuel cell stack in response to the instructions of the safety linkage controller.

[0100] The electrical safety subsystem is communicatively connected to the safety linkage controller and is used to respond to the instructions of the safety linkage controller to cut off the main circuit of the fuel cell stack and release energy.

[0101] In some embodiments, the safety linkage controller is configured to execute the following linkage sequence: first control the operation of the electrical safety subsystem, and then control the operation of the explosion suppressant storage and injection subsystem.

[0102] This system, deeply coupled with an online electrochemical impedance spectroscopy (EIS) diagnostic system, forms a complete "prediction-decision-protection" closed loop. Its core lies in automatically and rapidly executing explosion suppression actions based on the membrane health status (SOH) and risk level output by the EIS diagnostic system.

[0103] The working principle of this application is based on the core ideas of "predictive risk-driven" and "multiple security mechanism synergy".

[0104] 1. Risk Perception and Decision-Making Principles: The online EIS diagnostic system, acting as the "sensory organ" of this application, continuously monitors the health status of the proton exchange membrane. Its output SOH and RUL are direct indicators for quantifying risk. The safety linkage controller, acting as the "brain," determines whether to activate the explosion suppression procedure based on preset risk level thresholds.

[0105] 2. Mechanism of Action of the Explosion Suppressant: This application innovatively selects fluorinated ketone-based clean explosion suppressants such as perfluorohexanone. Its mechanism of action is dual:

[0106] Chemical inhibition: In the combustion chain reaction, perfluorohexanone decomposes at high temperatures, effectively capturing the gases produced during combustion. , , Free radicals interrupt the chain reaction.

[0107] Physical effects: It rapidly vaporizes and absorbs a large amount of heat, lowering the temperature of the reaction zone; at the same time, its vapor can dilute the oxygen concentration.

[0108] 3. Key Innovative Insights: Unlike extinguishing deep thermal runaway fires in lithium batteries, this application aims to establish an explosion-suppressing atmosphere within a closed cathode channel before the deflagration of the hydrogen-oxygen mixture. In this scenario, perfluorohexanone's gas-phase explosion suppression efficiency and material compatibility advantages are fully utilized, thereby overcoming the technical biases held by those skilled in the art due to its poor performance in lithium battery applications.

[0109] 4. Principle of safely eliminating ignition sources: Almost simultaneously with the injection of the explosion suppressant, the system cuts off the external circuit through a fast circuit breaker and rapidly consumes the electrical energy stored in the double electric layer inside the fuel cell stack through an active energy discharge circuit, completely eliminating the "electric ignition source" inside the fuel cell stack. Working in synergy with the explosion suppressant, it completely destroys the combustion conditions.

[0110] In some embodiments, referring to Table 2, the anti-knock agent storage and injection subsystem includes:

[0111] A dedicated explosion suppressant storage tank is used to store liquid explosion suppressant, which is a clean explosion suppressant that does not damage the proton exchange membrane;

[0112] A high-speed solenoid valve, the inlet of which is connected to the outlet of the dedicated explosion suppressant storage tank via a pipeline;

[0113] A fine atomizing nozzle is connected to the outlet of the high-speed solenoid valve and is installed in the cathode air inlet pipe of the fuel cell stack.

[0114] In some embodiments, the interior of the dedicated explosion suppressant storage tank employs a gas-liquid separation design.

[0115]

[0116] In some embodiments, referring to Table 3, the electrical safety subsystem includes:

[0117] A main circuit fast circuit breaker is connected in series on the main output bus of the fuel cell stack to disconnect the main circuit of the fuel cell stack.

[0118] An active energy discharge circuit is connected in parallel with the output terminal of the fuel cell stack via a switching element to consume the electrical energy stored inside the stack.

[0119]

[0120] In some embodiments, the steps of the active explosion suppression method for fuel cells based on membrane health status early warning provided in this application are described in conjunction with the active explosion suppression system for fuel cells based on membrane health status early warning provided in the above embodiments.

[0121] Step 1: Continuous Monitoring and Diagnosis. The online EIS system diagnoses the fuel cell stack at a set cycle (e.g., every 5 minutes), updates the SOH and RUL values, and broadcasts them via the CAN bus.

[0122] Step Two: Risk Decision-Making. The safety linkage controller monitors the CAN bus to obtain the latest SOH and RUL. The controller's internal decision-making algorithm determines the current risk level based on preset thresholds.

[0123] Step 3: Tiered Response. If it is Level 1 or 2, perform actions such as issuing a warning, recording, or suggesting power reduction. If it jumps to Level 3, immediately interrupt the current task and enter the emergency explosion suppression procedure.

[0124] Step Four: Emergency Explosion Suppression Interlock. The controller strictly follows the sequence of "power off and energy release first, then explosion suppression injection" to send commands to each actuator. The explosion suppressant is injected into the cathode air path and enters the fuel cell stack with the airflow, creating an explosion suppression atmosphere in the membrane electrode area. Electrical energy is rapidly released, eliminating the ignition source.

[0125] Step 5: Status Feedback and System Lockout. After the action is completed, the system will provide status feedback and lock out. The fuel cell system can only be restarted after on-site inspection and reset by a qualified professional.

[0126] Compared with existing technologies, this application has the following outstanding innovative features:

[0127] (1) Methodological innovation: It pioneered the "active explosion suppression based on predictive membrane health diagnosis" safety paradigm, which transformed fire safety actions from "post-event remediation" to "pre-event prevention", thus achieving inherent safety.

[0128] (2) Breakthrough in technology selection and overcoming of bias: Perfluorohexanone and other fluorinated ketone cleaning agents are clearly selected as fuel cell-specific anti-knock agents, and an in-depth principle analysis of their applicability in this scenario is provided: their gas phase anti-knock mechanism and excellent material compatibility make them particularly suitable for suppressing hydrogen-oxygen deflagration inside fuel cells, thereby overcoming the technical bias of those skilled in the art due to their poor performance in lithium battery fires, and opening up new fields for the application of this type of preparation.

[0129] (3) Depth of system integration: The system has achieved deep coupling and millisecond-level linkage of the three major subsystems: “EIS early warning system”, “dedicated explosion suppression system” and “electrical safety system”, and has built a cross-domain, collaborative, and in-depth defense system.

[0130] (4) Innovation of application scenarios: A new application path of injecting the explosion suppressant into the cathode air flow path is proposed, which utilizes the air flow to achieve rapid and uniform distribution of the explosion suppressant and directly act on the core risk area.

[0131] (5) Precision of control strategy: A linkage control sequence with a nanosecond delay was designed, strictly following the safety logic of "eliminating the ignition source first and then establishing the explosion suppression atmosphere", which ensures the efficiency and reliability of the protective action and avoids secondary risks that may be caused by improper action sequence.

[0132] Example 1

[0133] Active explosion suppression application of on-board fuel cell systems. This embodiment uses a commercial fuel cell city bus as an application scenario to describe the implementation method of the system in detail.

[0134] (1) System integration and installation:

[0135] Hardware setup:

[0136] Explosion suppressant storage tank: A 300mL aluminum alloy pressure-resistant tank is selected and installed on a special bracket in the fuel cell compartment, close to the cathode air intake pipe.

[0137] Injection Unit: The high-speed solenoid valve (model: SMCVDW20) is directly installed at the tank outlet and connected to the atomizing nozzle via a φ6mm PTFE pipe. The nozzle (model: SprayingSystems1 / 4G-SS+) is welded at a 45° angle to an aluminum pipe approximately 15cm after the cathode air filter and before the fuel cell inlet.

[0138] Electrical safety module: A high-power solid-state relay (model: VishayVOW112) is connected in series in the main positive bus, close to the fuel cell stack output terminal. An energy discharge resistor network (resistance value 2.2Ω, power 5kW) is connected in parallel across the fuel cell stack via a MOSFET switch (model: InfineonIPA95R1K2P5).

[0139] Controller: The safety linkage controller (developed based on the NXPS32K144 microcontroller) and the fuel cell controller (FCU) are installed together in the electronic control box in the front compartment of the vehicle.

[0140] (2) Software configuration:

[0141] Risk assessment and linkage control algorithms are embedded in the safety linkage controller.

[0142] Set risk thresholds: SOH < 80% (Level 1), SOH < 70% (Level 2), SOH < 60% or RUL < 24h (Level 3).

[0143] The injection time of the explosion suppressant is configured to be 2.0 seconds, and the expected injection dose is approximately 40 mL.

[0144] (3) Work process:

[0145] When the vehicle is driving normally, the EIS diagnostic system performs an online diagnostic every 5 minutes.

[0146] When the system detects that the SOH of a certain fuel cell stack has continued to drop to 58% due to membrane water management imbalance, the EIS system will issue a message with a risk level of Level 3 via the CAN bus.

[0147] The safety linkage controller completes the decision within 10ms and executes it according to the preset sequence:

[0148] t=0ms: The solid-state relay cuts off the main circuit.

[0149] t=1ms: Close the MOSFET switch of the energy discharge circuit.

[0150] t=5ms: The high-speed solenoid valve is activated and remains in operation for 2000ms.

[0151] After being atomized, the perfluorohexanone anti-knock agent enters the fuel cell stack along with the cathode air, and the stack voltage is discharged from 380V to below 30V within 500ms.

[0152] The system triggered an audible and visual alarm and displayed "Safety system activated, please contact service immediately" on the dashboard. The vehicle entered limp mode and must be inspected and reset by authorized personnel on-site before it can be restarted.

[0153] Example 2

[0154] Active explosion suppression application in stationary hydrogen energy storage power stations. This example uses a 1MW containerized hydrogen energy storage power station as an application scenario.

[0155] System integration and installation:

[0156] (1) Hardware layout:

[0157] Since the power plant contains four 250kW fuel cell stack modules, each module is equipped with an independent explosion suppressant injection unit, but they share a central control cabinet.

[0158] Explosion suppressant storage tank: A 5L stainless steel common storage tank is used, which is connected to 4 solenoid valves through a pressure reducing valve and a distributor.

[0159] Injection Unit: An atomizing nozzle is installed on the cathode inlet branch pipe of each fuel cell module. Explosion-proof solenoid valves (model: Burkert6213) are selected.

[0160] Electrical safety: Each fuel cell stack module is equipped with an independent solid-state circuit breaker and a bleed resistor, which are controlled by a central controller.

[0161] (2) Software configuration:

[0162] Advanced diagnostic and control software runs on a central industrial control computer (based on an Intel i7 processor), integrating more complex AI models.

[0163] Set more conservative thresholds: SOH < 85% (Level 1), SOH < 75% (Level 2), SOH < 68% or RUL < 48h (Level 3).

[0164] It integrates with the power plant energy management system (EMS) to enable predictive maintenance scheduling.

[0165] (3) Work process:

[0166] The power station uses off-peak electricity at night for "electricity-to-hydrogen" conversion and generates "hydrogen-to-electricity" during the day.

[0167] The central diagnostic system found that the SOH of the #3 fuel cell module decreased linearly from 82% to 66% within two weeks, and the high-frequency peak area of ​​the DRT increased by 15%, with a RUL calculated to be 36 hours.

[0168] The system determined the risk to be Level 3 and sent an alarm to EMS while executing the explosion suppression linkage sequence.

[0169] EMS automatically adjusted the power generation plan, took the #3 fuel cell stack offline, and generated a work order to notify the maintenance team to prepare to replace the fuel cell stack.

[0170] Explosion suppression prevents potential operational failures, while predictive maintenance avoids unplanned downtime, improving the overall operational efficiency of the power plant.

[0171] In some embodiments, a safety linkage controller is provided for active explosion suppression of fuel cells, wherein the controller performs the steps of the method described in the above embodiments.

[0172] In some embodiments, a fuel cell device is provided, including a fuel cell stack, the device further including the system described in the above embodiments.

[0173] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A method for active explosion suppression of fuel cells based on membrane health status early warning, characterized in that, include: Receive health status parameters of the proton exchange membrane in the fuel cell stack from the online electrochemical impedance spectroscopy diagnostic system; Based on the health status parameters and preset thresholds, the current risk level is determined; If the risk level is hazardous, the emergency explosion suppression linkage control sequence will be automatically triggered and executed, including: Send a command to the electrical safety subsystem to disconnect the main circuit of the fuel cell stack and release energy; A command is sent to the explosion suppressant storage and injection subsystem to open the high-speed solenoid valve and inject the explosion suppressant into the cathode air flow path of the fuel cell stack.

2. The method according to claim 1, characterized in that, It also includes, after the explosion suppression linkage control sequence is completed, putting the fuel cell stack into a safety latching state, which can only be restarted after manual reset.

3. The method according to claim 1, characterized in that, When executing the linkage control sequence, the main circuit is first cut off and the discharge energy is released, and then the explosion suppressant is injected.

4. The method according to claim 1, characterized in that, The explosion suppressant is a clean explosion suppressant that does not damage the proton exchange membrane.

5. The method according to claim 1, characterized in that, The determination of the current risk level based on the health status parameters and preset thresholds specifically includes: Note level: When the health status parameter is lower than the first threshold, log the information and send a maintenance reminder; Warning level: When the health status parameter is less than the second threshold, or the remaining lifetime is less than the first time threshold, a command is sent to the fuel cell controller (FCU) to limit the maximum output power of the fuel cell stack to a preset level; Hazard Level: When the health status parameter is less than the third threshold, or the remaining lifespan is less than the second time threshold, or the electrochemical impedance spectroscopy characteristic parameter undergoes a sudden change that exceeds the preset range, the emergency explosion suppression linkage control sequence will be immediately triggered and executed.

6. A fuel cell active explosion suppression system based on membrane health status early warning, characterized in that, include: An online electrochemical impedance spectroscopy diagnostic system is used to continuously monitor the health status of the proton exchange membrane in a fuel cell stack and output health status parameters and remaining lifetime parameters. A safety linkage controller, communicatively connected to the online electrochemical impedance spectroscopy diagnostic system, is used to receive the health status and remaining lifetime parameters and make decisions based on a preset risk level threshold. This includes: receiving health status parameters of the proton exchange membrane of the fuel cell stack continuously monitored by the online electrochemical impedance spectroscopy diagnostic system; determining the current risk level based on the health status parameters and the preset threshold; and automatically triggering and executing an emergency explosion suppression linkage control sequence if the risk level is dangerous. The emergency explosion suppression linkage control sequence includes: sending a command to the electrical safety subsystem to cut off the main circuit of the fuel cell stack and release energy; and sending a command to the explosion suppressant storage and injection subsystem to open the high-speed solenoid valve and inject the explosion suppressant into the cathode air path of the fuel cell stack. The explosion suppressant storage and injection subsystem is communicatively connected to the safety linkage controller and is used to inject the explosion suppressant into the cathode air flow path of the fuel cell stack in response to the instructions of the safety linkage controller. The electrical safety subsystem is communicatively connected to the safety linkage controller and is used to respond to the instructions of the safety linkage controller to cut off the main circuit of the fuel cell stack and release energy.

7. The system according to claim 6, characterized in that, The anti-knock agent storage and injection subsystem includes: A dedicated explosion suppressant storage tank is used to store liquid explosion suppressant, which is a clean explosion suppressant that does not damage the proton exchange membrane; A high-speed solenoid valve, the inlet of which is connected to the outlet of the dedicated explosion suppressant storage tank via a pipeline; A fine atomizing nozzle is connected to the outlet of the high-speed solenoid valve and is installed in the cathode air inlet pipe of the fuel cell stack.

8. The system according to claim 7, characterized in that, The internal structure of the dedicated explosion suppressant storage tank adopts a gas-liquid separation design.

9. The system according to claim 6, characterized in that, The electrical safety subsystem includes: A main circuit fast circuit breaker is connected in series on the main output bus of the fuel cell stack to disconnect the main circuit of the fuel cell stack. An active energy discharge circuit is connected in parallel with the output terminal of the fuel cell stack via a switching element to consume the electrical energy stored inside the stack.

10. The system according to claim 6, characterized in that, The safety linkage controller is configured to execute the following linkage sequence: First, control the operation of the electrical safety subsystem, and then control the operation of the explosion suppressant storage and injection subsystem.

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