Airtight structure of flow battery and airtight detection method thereof

Abstract

The invention relates to the field of batteries, and provides an airtight structure of a flow battery and an airtight detection method thereof. The airtight structure of the flow battery comprises an electric pile module, the electric pile module comprises at least one single battery, and electrolyte is accommodated in the single battery; an inner sealing strip and an outer sealing strip are arranged on the single battery, and a closed gas chamber is defined between the inner sealing strip and the outer sealing strip; the pressure control unit is communicated with the gas chamber and is used for supplying a sealing medium to the gas chamber and maintaining the pressure of the sealing medium to be higher than that of the electrolyte so as to form a pressure gradient barrier; and the voltage monitoring module is used for monitoring the voltage of at least one single battery. According to the airtight structure of the flow battery, an efficient and reliable sealing effect can be realized, the accuracy and sensitivity of leakage detection are greatly improved, and the types of inner leakage and outer leakage can be accurately distinguished and the leakage position can be positioned according to a voltage fluctuation mode and air pressure change characteristics.

Description

Technical Field

[0001] This invention relates to the field of batteries, and provides a gas-tight structure for a flow battery and a method for detecting its gas-tightness. Background Technology

[0002] In the widespread application of flow batteries, ensuring their operational safety and reliability is paramount. As a key technology for large-scale energy storage systems, leakage has become a critical factor affecting the performance and safety of these systems. Leakage can lead to electrolyte loss, performance degradation, and even environmental pollution and safety accidents. Therefore, developing efficient and reliable leakage detection technologies is a crucial step in ensuring the safe operation of flow batteries.

[0003] Currently, mainstream leak detection methods include direct observation, pressure monitoring, flow monitoring, electrolyte composition monitoring, and gas detection. Direct observation is the most basic method, simple to operate and inexpensive, but its ability to detect concealed leaks and low-flow-rate seepage is limited, and detection is difficult. Pressure monitoring and flow monitoring can achieve quantitative detection, but both have significant limitations in practical applications. For example, fluctuations in ambient temperature and interference from pump pulsations can affect the accuracy of the detection results. Electrolyte composition monitoring and gas detection have high sensitivity, but the corresponding equipment is expensive and requires specialized operation. Furthermore, long analysis cycles, susceptibility to environmental conditions, and ineffectiveness against non-volatile leaks also limit their widespread application. Summary of the Invention

[0004] This invention provides an airtight structure for a flow battery to address the shortcomings of insufficient airtightness in related technologies.

[0005] This invention also provides an airtightness detection method.

[0006] A first aspect of the present invention provides a hermetically sealed structure for a flow battery, comprising: A fuel cell stack module, the fuel cell stack module comprising at least one single cell, the single cell containing an electrolyte; The single battery is provided with an inner sealing strip and an outer sealing strip, and a closed gas chamber is defined between the inner sealing strip and the outer sealing strip; A pressure control unit, which is connected to the gas chamber, is used to supply a sealing medium to the gas chamber and maintain the pressure of the sealing medium higher than the pressure of the electrolyte to form a pressure gradient barrier. A voltage monitoring module is provided for monitoring the voltage of at least one of the single batteries.

[0007] According to one embodiment of the present invention, the sealing medium is an inert gas.

[0008] According to one embodiment of the present invention, the sealing medium is water.

[0009] According to one embodiment of the present invention, the device further includes a conductivity meter, wherein the pressure control unit includes a circuit for circulating water, and the conductivity meter is disposed in the circuit for monitoring the conductivity of the water.

[0010] According to one embodiment of the present invention, the fuel cell stack module includes a plurality of stacked individual cells; The gas chambers of the multiple individual cells are interconnected through gas channels to form a total sealed medium channel that runs through the stack module.

[0011] According to one embodiment of the present invention, the pressure control unit includes a sealing medium source, a pressure regulating valve, and a controller; The controller is used to control the opening of the pressure regulating valve according to the monitored pressure of the sealing medium, so as to maintain the pressure of the sealing medium higher than the pressure of the electrolyte.

[0012] A second aspect of the present invention provides a method for detecting the airtightness of the airtight structure of a flow battery as described above, comprising: The pressure control unit supplies a sealing medium to the gas chamber and maintains the pressure of the sealing medium at a level higher than that of the electrolyte. The voltage of at least one of the single batteries is monitored in real time using the voltage monitoring module. The pressure control unit monitors the pressure of the sealing medium in the gas chamber in real time. Based on the monitored voltage changes of the individual cells and the pressure changes of the sealing medium, it is determined whether there is a leak in the fuel cell stack module.

[0013] According to an embodiment of the present invention, the step of determining whether the fuel cell module has a leak includes: When abnormal fluctuations in the voltage of the single battery are detected, and the pressure of the sealing medium continues to drop, it is determined that an internal leakage of electrolyte has occurred.

[0014] According to one embodiment of the present invention, the airtightness detection method for the flow battery further includes: The single cell exhibiting abnormal voltage fluctuations was identified as the location of the leak.

[0015] According to an embodiment of the present invention, the step of determining whether the fuel cell module has a leak includes: When the voltage of all individual cells remains stable and the pressure of the sealing medium continues to decrease, it is determined that electrolyte leakage has occurred.

[0016] According to the first aspect of the present invention, the flow battery provides an airtight structure in which a pressure control unit continuously supplies a sealing medium and dynamically adjusts the pressure to maintain a stable pressure gradient barrier in the gas chamber that is always higher than the electrolyte pressure. Through pressure sensing and adjustment, a dynamic balance is formed, which can adapt to minor fluctuations in the electrolyte pressure and maintain a constant pressure barrier against the electrolyte. Compared to traditional static seals, this dynamic gas pressure seal can actively resist the leakage tendency of the electrolyte, effectively preventing electrolyte leakage into the gas chamber or to the outside, significantly improving the sealing efficiency and long-term reliability, and meeting the sealing requirements for long-term operation of the flow battery. The voltage monitoring module and the pressure control unit provide two core parameters: single-cell voltage and gas chamber pressure. Subsequent leak detection can be achieved by collaboratively analyzing the changing characteristics of these two parameters: if the single-cell voltage fluctuates abnormally while the gas chamber pressure continues to decrease, it can be accurately determined that there is internal electrolyte leakage; if all single-cell voltages remain stable, but only the gas chamber pressure continues to decrease, it can be accurately determined that there is external electrolyte leakage. This dual-parameter collaborative analysis mode completely solves the problem of misjudgment caused by single-parameter monitoring, significantly improving the accuracy of leak detection. Simultaneously, the sensitivity of voltage to electrolyte mixing and the rapid response of pressure to seal failure enable the system to capture minute signal changes in the early stages of a leak, significantly improving detection sensitivity. Furthermore, it can accurately distinguish leak types based on parameter change patterns, providing a basis for locating the leak. The pressure control unit and voltage monitoring module can form a complete closed-loop control system with subsequent control units: the pressure control unit automatically maintains the pressure gradient, the voltage monitoring module automatically collects voltage data, and the control unit automatically analyzes parameters and determines the leak, achieving fully automated operation from real-time monitoring and intelligent judgment to pressure compensation.

[0017] According to the second aspect of the present invention, the airtightness detection method for the airtight structure of a flow battery continuously supplies a sealing medium and maintains a pressure higher than that of the electrolyte through a pressure control unit. The resulting pressure gradient barrier is not a static seal, but rather dynamically adjusts the supply according to real-time pressure changes, always maintaining an active blocking effect on the electrolyte. This dynamic adjustment mode can adapt to the small fluctuations in electrolyte pressure during the operation of the flow battery, avoiding the seal failure caused by pressure imbalance in static seals, fundamentally improving the long-term reliability of the seal, and providing a stable basic sealing environment for subsequent leak detection. The coordinated implementation of voltage monitoring and pressure monitoring solves the limitations of single-parameter monitoring: voltage data can accurately reflect whether electrolyte mixing has occurred, and pressure data can directly reflect whether the seal has failed. By comprehensively analyzing the change characteristics of the two types of data, the type of leak can be effectively distinguished, avoiding misjudgments such as the inability to determine the direction of leak due to relying solely on pressure data or the inability to identify external leaks due to relying solely on voltage data. At the same time, the sensitivity of voltage to electrolyte mixing and the rapid response of pressure to seal failure enable the system to capture minute data changes in the early stages of leakage, significantly improving the sensitivity of leak detection. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in this 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 some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic perspective view of a single battery provided by the present invention.

[0020] Figure 2 This is a schematic diagram of the fuel cell stack provided by the present invention.

[0021] Figure 3 This is a schematic diagram of the airtightness testing method with water as the sealing medium provided by the present invention.

[0022] Figure label: 100. Single cell; 102. Inner sealing strip; 104. Outer sealing strip; 106. Gas chamber; 108. Conductivity meter; 110. Sealing medium source; 112. Pressure regulating valve. Detailed Implementation

[0023] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0024] like Figures 1 to 3As shown, a first aspect embodiment of the present invention provides a hermetically sealed structure for a flow battery, comprising: A fuel cell module, comprising at least one single cell 100, wherein the single cell 100 contains an electrolyte. The single battery 100 is provided with an inner sealing strip 102 and an outer sealing strip 104, and a closed gas chamber 106 is defined between the inner sealing strip 102 and the outer sealing strip 104. The pressure control unit is connected to the gas chamber 106 and is used to supply the sealing medium to the gas chamber 106 and maintain the pressure of the sealing medium higher than the pressure of the electrolyte to form a pressure gradient barrier. Voltage monitoring module, used to monitor the voltage of at least one single cell 100.

[0025] According to the first aspect of the present invention, the flow battery provides an airtight structure in which a pressure control unit continuously supplies a sealing medium and dynamically adjusts the pressure to maintain a stable pressure gradient barrier in the gas chamber 106 that is always higher than the electrolyte pressure. Through pressure sensing and adjustment, a dynamic balance is formed, which can adapt to minor fluctuations in the electrolyte pressure and maintain a constant pressure barrier against the electrolyte. Compared to traditional static seals, this dynamic gas pressure seal can actively resist the leakage trend of the electrolyte, effectively preventing electrolyte leakage into the gas chamber 106 or to the outside, significantly improving the efficiency and long-term reliability of the seal, and meeting the sealing requirements for long-term operation of the flow battery. The voltage monitoring module and the pressure control unit provide two core parameters: the voltage of a single cell 100 and the pressure of the gas chamber 106. Leakage detection can be achieved by synergistically analyzing the changing characteristics of these two parameters: if the voltage of a single cell 100 fluctuates abnormally while the pressure of the gas chamber 106 continues to decrease, it can be accurately determined that there is internal electrolyte leakage; if the voltage of all single cells 100 remains stable, but the pressure of the gas chamber 106 continues to decrease, it can be accurately determined that there is external electrolyte leakage. This dual-parameter collaborative analysis mode completely solves the problem of misjudgment caused by single-parameter monitoring, significantly improving the accuracy of leak detection. Simultaneously, the sensitivity of voltage to electrolyte mixing and the rapid response of pressure to seal failure enable the system to capture minute signal changes in the early stages of a leak, significantly improving detection sensitivity. Furthermore, it can accurately distinguish leak types based on parameter change patterns, providing a basis for locating the leak. The pressure control unit and voltage monitoring module can form a complete closed-loop control system with subsequent control units: the pressure control unit automatically maintains the pressure gradient, the voltage monitoring module automatically collects voltage data, and the control unit automatically analyzes parameters and determines the leak, achieving fully automated operation from real-time monitoring and intelligent judgment to pressure compensation.

[0026] Please continue reading Figures 1 to 3The fuel cell stack module, as the core energy generation unit of the flow battery, includes at least one single cell 100. Each single cell 100 has an independent enclosed containment space specifically for containing electrolyte, ensuring that the electrolyte is stably stored inside the single cell 100 and does not come into contact with the outside. The structural design of the single cell 100 is adapted to the storage and reaction requirements of the electrolyte. An inner sealing strip 102 and an outer sealing strip 104 are fixedly arranged along a predetermined contour on its outer periphery or the outer edge of the electrolyte containment space. The inner sealing strip 102 is close to the electrolyte containment space and is arranged directly around the outer periphery of the electrolyte containment space to initially prevent the electrolyte from diffusing outward. The outer sealing strip 104 is located outside the inner sealing strip 102, maintaining a certain distance from the inner sealing strip 102, and also extends along the contour of the single cell 100. Both ends of the inner sealing strip 102 and the outer sealing strip 104 are closed by a sealing connection, forming a closed gas chamber 106 without openings. The gas chamber 106 surrounds the outside of the electrolyte containing space, forming a protective layer, which provides a carrier for the subsequent filling of the sealing medium and pressure maintenance.

[0027] The pressure control unit, serving as the core for supplying and regulating the sealing medium, is connected to the gas chamber 106 via a sealed pipeline. Both ends of the sealed pipeline are sealed to the medium output port of the pressure control unit and the medium input port of the gas chamber 106, respectively, ensuring no leakage of the sealing medium during transmission. The pressure control unit has functions for storing, transporting, and regulating the sealing medium, continuously supplying it to the gas chamber 106. Simultaneously, the pressure control unit incorporates a pressure sensing component that monitors the pressure of the sealing medium within the gas chamber 106 in real time and dynamically adjusts the medium supply through its own regulating components, always maintaining the pressure of the sealing medium higher than the pressure of the electrolyte inside the single cell 100, thus creating a stable pressure gradient barrier within the gas chamber 106.

[0028] The voltage monitoring module includes a voltage detection component and a data transmission component. The voltage detection component establishes an electrical connection with at least one individual cell 100 in the fuel cell stack module. If the fuel cell stack module contains multiple individual cells 100, a corresponding voltage detection point can be configured for each individual cell 100 to ensure that voltage data of each individual cell 100 can be collected. The voltage detection component collects the voltage signal of the individual cell 100 in real time, and the data transmission component transmits the collected voltage data to the control or analysis unit of the flow battery in real time. This provides crucial voltage signal evidence for subsequent judgment of whether there is a leak in the fuel cell stack module by combining pressure data, avoiding misjudgment of the leak type due to relying solely on pressure data.

[0029] According to one embodiment of the present invention, the sealing medium is an inert gas.

[0030] In one embodiment of the present invention, the airtight structure of the flow battery uses an inert gas as the sealing medium. The inner sealing strip 102 and outer sealing strip 104 of the single cell 100 are arranged along the edge, parallel to each other and spaced a certain distance apart, jointly defining a closed annular gas chamber 106. This chamber surrounds the electrolyte-containing area of ​​the single cell 100, has no openings, and has good sealing performance. The pressure control unit is sealed to the gas chamber 106 via a pipe. After the inert gas is output from the sealing medium source 110, it enters the gas chamber 106 through the pressure regulating valve 112. The pressure control unit has a built-in pressure sensor that collects the inert gas pressure data in the gas chamber 106 in real time and transmits it to the controller. The controller dynamically adjusts the opening of the pressure regulating valve 112 according to a preset pressure difference (the sealing medium pressure is higher than the electrolyte pressure), continuously replenishing the inert gas, maintaining the pressure stability in the gas chamber 106, and forming a stable pressure gradient barrier. The detection probe of the voltage monitoring module is connected to the electrode of each single cell 100 to collect the voltage signal of the single cell 100 in real time and transmit it synchronously to the system control center to form a collaborative monitoring with the pressure data.

[0031] Inert gas, as a sealing medium, is chemically stable and does not react with the electrolyte. The controller maintains a stable pressure gradient higher than that of the electrolyte by adjusting the pressure regulating valve 112 in real time, forming an efficient and reliable sealing barrier that effectively prevents electrolyte from leaking inward or outward, thereby improving the stability and durability of the seal.

[0032] The system employs dual-parameter monitoring of voltage and gas pressure. When there is internal electrolyte leakage, the electrolyte inside the single cell 100 mixes, causing abnormal voltage fluctuations. Simultaneously, the internal leakage consumes the inert gas in the gas chamber 106, leading to a continuous pressure drop. Conversely, when there is external electrolyte leakage, the electrolyte inside the single cell 100 remains unmixed, and the voltage remains stable, but the pressure in the gas chamber 106 continuously decreases due to the leakage of the sealing medium. By analyzing the changing characteristics of these two parameters, the accuracy and sensitivity of leak detection are significantly improved, accurately distinguishing between internal and external leaks and resolving the misjudgment problem associated with single-parameter detection.

[0033] The pressure control unit, consisting of a sealing medium source 110, a pressure regulating valve 112, a controller, and a voltage monitoring module, forms a complete closed-loop control system. Each component is modularly designed, operates independently, and shares data in real time. The controller automatically compensates for inert gas based on pressure data, and the control center automatically analyzes dual-parameter data to determine leakage, achieving full automation from monitoring and assessment to compensation. The modular design allows each functional unit to be maintained or upgraded individually, ensuring overall system reliability while reducing maintenance costs.

[0034] According to one embodiment of the present invention, the sealing medium is water.

[0035] In one embodiment of the present invention, the airtight structure of the flow battery uses water as the sealing medium. The gas chamber 106 defined by the inner sealing strip 102 and the outer sealing strip 104 of a single cell 100 is a closed cavity structure, which is sealed and connected to the water circulation loop of the pressure control unit. The water circulation loop of the pressure control unit includes a water pump, a pipe, and a water storage container. The water pump delivers water from the water storage container to the gas chamber 106, and a pressure monitoring element is installed on the pipe to collect water pressure data in real time. The controller adjusts the output power of the water pump according to the monitored pressure data to maintain the water pressure in the gas chamber 106 continuously higher than the electrolyte pressure, forming a liquid pressure gradient barrier. The voltage monitoring module continuously collects the voltage data of each single cell 100 and transmits it synchronously with the pressure data to the system control center to collaboratively complete leak detection. Water, as a sealing medium, is non-chemically corrosive and immiscible with the electrolyte, ensuring a safe and stable sealing process.

[0036] Dynamic air pressure sealing technology extends to liquid pressure control. By adjusting the water pump power through the controller, a stable pressure gradient of water is maintained, resulting in better sealing of the liquid medium and forming a highly efficient and reliable pressure barrier. This effectively prevents electrolyte leakage, adapts to sealing requirements under different working conditions, and improves the adaptability of the sealing system.

[0037] The system employs dual-parameter monitoring of voltage and water pressure, taking into account the physical properties of water. When internal leakage occurs, electrolyte intrusion into the water medium causes abnormal voltage fluctuations in a single cell (100V), while the water pressure continuously decreases due to medium mixing or leakage. In the case of external leakage, the voltage remains stable while the water pressure drops. This dual-parameter synergistic analysis significantly improves the accuracy and sensitivity of leak detection, precisely distinguishing between internal and external leaks and overcoming the limitation of single pressure monitoring in determining the type of leak.

[0038] The water circulation loop, pressure control components, and voltage monitoring module adopt a modular design, forming a complete closed-loop control system. The water pump, pressure monitoring element, and controller automatically complete pressure compensation, and the control center automatically analyzes parameter data to determine leakage, achieving fully automated operation. Each module is assembled independently, allowing for individual maintenance of the water circulation loop or voltage monitoring module. Upgrades can be performed by replacing corresponding components, ensuring system reliability while facilitating maintenance and upgrades.

[0039] According to one embodiment of the present invention, a conductivity meter 108 is also included. The pressure control unit includes a loop for circulating water, and the conductivity meter 108 is disposed in the loop for monitoring the conductivity of the water.

[0040] In one embodiment of the present invention, the airtight structure of the flow battery, based on water as the sealing medium, adds a conductivity meter 108. The circulating water circuit of the pressure control unit includes a water storage container, a circulating pump, an inlet pipe, a return pipe, and valves. The inlet pipe and the return pipe are respectively sealed to both ends of the gas chamber 106, forming a closed loop. The conductivity meter 108 is installed on the return pipe and connected in series with the circulating loop to monitor the conductivity data of the circulating water in real time. The circulating pump drives water to flow continuously between the loop and the gas chamber 106. The pressure monitoring element collects the pressure data of the circulating water. The controller adjusts the power of the circulating pump and the valve opening according to the pressure data to maintain the water pressure higher than the electrolyte pressure. The voltage monitoring module collects the voltage data of a single cell 100. The detection data of the conductivity meter 108, the pressure monitoring element, and the voltage monitoring module are all transmitted to the system control center for collaborative leakage detection.

[0041] Dynamic air pressure sealing technology achieves continuous circulation and pressure stability of water medium through a circulating water circuit. The flowing water forms a dynamic pressure gradient barrier, resulting in a more uniform sealing effect. This avoids seal failure caused by local pressure imbalance of static water medium, thus improving the reliability and longevity of the seal.

[0042] The system monitors voltage, water pressure, and conductivity in tandem. In addition to the two parameters, conductivity data is added. When there is internal leakage of the electrolyte, the mixing of the electrolyte with the circulating water will cause a significant change in conductivity. Combined with abnormal voltage fluctuations and water pressure drops, the sensitivity and accuracy of leak detection are further improved, accurately distinguishing between internal and external leaks, and capturing minute changes in the early stages of leakage earlier.

[0043] According to one embodiment of the present invention, the fuel cell stack module includes a plurality of stacked single cells 100; The gas chambers 106 of multiple single cells 100 are interconnected through gas channels to form a total sealed medium channel that runs through the stack module.

[0044] In one embodiment of the present invention, the fuel cell stack module is composed of multiple individual cells 100 arranged sequentially along the stacking direction. Each individual cell 100 has an inner sealing strip 102 and an outer sealing strip 104 defining an independent gas chamber 106. Corresponding positions of the gas chambers 106 of adjacent individual cells 100 are provided with communication ports. The gas channel is a tubular structure, sealingly connecting the communication ports of adjacent individual cells 100, so that the gas chambers 106 of all individual cells 100 are interconnected, forming a total sealing medium channel running through the entire fuel cell stack module. A pressure control unit is sealed to one end of the total sealing medium channel, supplying sealing medium into the total channel, which is then evenly distributed to the gas chambers 106 of each individual cell 100. The controller adjusts the supply amount according to the pressure data in the total channel, maintaining a consistent pressure in all gas chambers 106 that is higher than the electrolyte pressure. A voltage monitoring module is equipped with an independent detection probe for each individual cell 100, collecting voltage data from each individual cell 100 to achieve full-coverage monitoring.

[0045] Dynamic gas pressure sealing technology achieves pressure synchronization of multiple single-cell 100 gas chambers 106 through the main channel of sealing medium. The controller adjusts the supply of sealing medium to form a uniform and stable pressure gradient barrier in all single-cell 100 areas, avoiding sealing failure caused by pressure imbalance of a single cell and improving the overall sealing reliability of the multi-cell stack.

[0046] The voltage monitoring module independently monitors each individual cell 100. Combined with the pressure data from the overall channel, when an internal leak occurs in a single cell 100, its voltage fluctuates abnormally, while the voltages of other cells remain stable. Simultaneously, the overall channel pressure continuously decreases. The leak location can be accurately pinpointed by identifying the cell number associated with the voltage fluctuation. In the case of an external leak, all cell voltages remain stable, with only the pressure decreasing. This dual-parameter collaborative analysis significantly improves the accuracy and location precision of leak detection in multi-cell stacks, resolving the difficulty in distinguishing the location of leaks in multiple cells.

[0047] According to one embodiment of the present invention, the pressure control unit includes a sealing medium source 110, a pressure regulating valve 112, and a controller; The controller is used to control the opening of the pressure regulating valve 112 according to the monitored pressure of the sealing medium, so as to maintain the pressure of the sealing medium higher than the pressure of the electrolyte.

[0048] In one embodiment of the present invention, the pressure control unit comprises a sealing medium source 110, a pressure regulating valve 112, a controller, and a pressure sensor. The sealing medium source 110 is connected to the input end of the pressure regulating valve 112 via a pipeline, and the output end of the pressure regulating valve 112 is connected to the gas chamber 106 or the main sealing medium channel via a pipeline. The pressure sensor is installed on a pipeline near the gas chamber 106 to collect the pressure data of the sealing medium in real time and transmit it to the controller via a data line. The controller has a built-in preset pressure threshold. It compares the real-time pressure data with the threshold. When the pressure is lower than the threshold, the controller issues a command to increase the opening of the pressure regulating valve 112 to increase the supply of sealing medium; when the pressure is higher than the threshold, it decreases the valve opening to decrease the supply, forming a dynamic pressure regulation closed loop. The pressure data and the voltage data from the voltage monitoring module are synchronized to the system control center in real time for collaborative leakage detection.

[0049] Dynamic air pressure sealing technology achieves precise dynamic adjustment of the sealing medium pressure through real-time linkage between the controller and the pressure regulating valve 112, maintains a stable pressure gradient barrier, avoids damage to the sealing strip due to excessive pressure or failure of the seal due to excessive pressure, improves the reliability and stability of the seal, and adapts to the sealing requirements under different working conditions.

[0050] The pressure data from the pressure control unit and the voltage data from the voltage monitoring module form a dual-parameter collaborative monitoring system. The pressure data transmitted by the controller reflects the sealing status in real time, while the voltage data reflects whether the electrolyte is mixed. By analyzing the timing and characteristics of the changes in both, the accuracy of leak detection is greatly improved, and the types of internal and external leaks can be accurately distinguished, thus overcoming the limitations of single-parameter detection.

[0051] A second aspect of the present invention provides a method for detecting the airtightness of the airtight structure of a flow battery as described above, comprising: The pressure control unit supplies the sealing medium to the gas chamber 106 and maintains the pressure of the sealing medium at a level higher than that of the electrolyte. The voltage of at least one single battery 100 is monitored in real time using a voltage monitoring module. The pressure control unit monitors the pressure of the sealing medium in the gas chamber 106 in real time. Based on the monitored voltage changes of single cell 100 and the pressure changes of the sealing medium, it is determined whether there is a leak in the fuel cell stack module.

[0052] According to the second aspect of the present invention, the airtightness detection method for the airtight structure of a flow battery continuously supplies a sealing medium and maintains a pressure higher than that of the electrolyte through a pressure control unit. The resulting pressure gradient barrier is not a static seal, but rather dynamically adjusts the supply according to real-time pressure changes, always maintaining an active blocking effect on the electrolyte. This dynamic adjustment mode can adapt to the small fluctuations in electrolyte pressure during the operation of the flow battery, avoiding the seal failure caused by pressure imbalance in static seals, fundamentally improving the long-term reliability of the seal, and providing a stable basic sealing environment for subsequent leak detection. The coordinated implementation of voltage monitoring and pressure monitoring solves the limitations of single-parameter monitoring: voltage data can accurately reflect whether electrolyte mixing has occurred, and pressure data can directly reflect whether the seal has failed. By comprehensively analyzing the change characteristics of the two types of data, the type of leak can be effectively distinguished, avoiding misjudgments such as the inability to determine the direction of leak due to relying solely on pressure data or the inability to identify external leaks due to relying solely on voltage data. At the same time, the sensitivity of voltage to electrolyte mixing and the rapid response of pressure to seal failure enable the system to capture minute data changes in the early stages of leakage, significantly improving the sensitivity of leak detection.

[0053] The general steps of the airtightness detection method for the airtightness structure of the flow battery provided in the second aspect embodiment of the present invention are as follows: The pressure control unit is activated. This unit establishes a stable connection with the gas chamber 106 via a pre-set sealed conduit. It first slowly delivers a sealing medium into the gas chamber 106, ensuring the medium evenly fills the entire chamber and expelling any residual air. During the medium delivery process, the pressure sensing component built into the pressure control unit continuously collects the pressure data of the sealing medium within the gas chamber 106 and feeds this data back to the regulating component inside the unit in real time. The regulating component dynamically adjusts the supply rate and quantity of the sealing medium based on the feedback pressure data: when the pressure is detected to be lower than the electrolyte pressure, the supply quantity is increased to raise the pressure; when the pressure is detected to be higher than the electrolyte pressure and reaches a stable range, the current supply quantity is maintained or slightly adjusted to ensure that the pressure of the sealing medium remains consistently higher than the electrolyte pressure, forming a stable pressure gradient barrier that prevents electrolyte leakage into the gas chamber 106 or the external space.

[0054] The voltage monitoring module is activated, and its voltage detection component establishes a reliable electrical connection with at least one individual cell 100 in the fuel cell stack module. The voltage detection component continuously captures the voltage signal of the individual cell 100 in real-time acquisition mode, and transmits the acquired voltage data to the flow battery's control and analysis unit in real time via its built-in data transmission component. During monitoring, the connection between the voltage detection component and the individual cell 100 is kept stable to avoid voltage data distortion caused by loose connections, ensuring that the voltage state of the individual cell 100 is accurately reflected.

[0055] While the pressure control unit maintains the pressure of the sealing medium, its built-in pressure sensing component switches to continuous monitoring mode. It is no longer solely used for pressure regulation but instead collects real-time pressure change data of the sealing medium within the gas chamber 106. The collected pressure data and voltage data from the voltage monitoring module are synchronously transmitted to the control and analysis unit, forming a dual data stream of voltage and pressure. The acquisition time points of the two types of data correspond to each other, ensuring that a time-series correlation can be established during subsequent analysis and avoiding judgment errors caused by data asynchrony.

[0056] After receiving the real-time transmitted voltage and pressure data, the control analysis unit performs trend analysis on the two types of data respectively: For voltage data, the system determines whether abnormal fluctuations occur; for pressure data, it determines whether a continuous decrease occurs. Subsequently, the control analysis unit combines the changes in both types of data to make a comprehensive judgment: if abnormal fluctuations in the voltage of a single cell 100 are detected, and the sealing medium pressure continues to decrease, it indicates that the electrolyte may have breached the inner sealing strip 102 and entered the gas chamber 106, indicating a leak in the fuel cell stack module; if the voltage of a single cell 100 remains stable, but the sealing medium pressure continues to decrease, it indicates that the sealing medium has breached the outer sealing strip 104 and leaked to the outside, also indicating a leak in the fuel cell stack module; if both types of data remain stable, the fuel cell stack module is determined to be leak-free.

[0057] According to one embodiment of the present invention, the step of determining whether a fuel cell module has a leak includes: When abnormal fluctuations in the voltage of a single cell 100 are detected, and the pressure of the sealing medium continues to drop, it is determined that an internal electrolyte leak has occurred.

[0058] In one embodiment of the present invention, the airtightness detection method for a flow battery determines electrolyte internal leakage according to the following process: A pressure control unit continuously supplies a sealing medium to the gas chamber 106, maintaining a pressure higher than the electrolyte pressure. A pressure sensor collects sealing medium pressure data at a preset frequency, and a voltage monitoring module simultaneously collects voltage data from each individual cell 100. The two collection frequencies are consistent to ensure data timing correspondence. After receiving the pressure and voltage data, the system control center performs fluctuation analysis on the voltage data. When the voltage data change amplitude exceeds a preset stable range within a certain time period, it is determined to be an abnormal voltage fluctuation. Simultaneously, trend analysis is performed on the pressure data. When the pressure data shows a downward trend for multiple consecutive collection cycles without rebound, it is determined to be a continuous pressure decrease. When both judgment conditions are met simultaneously, the system control center automatically outputs the judgment result of electrolyte internal leakage and triggers a corresponding early warning signal.

[0059] The dynamic pressure sealing technology maintains a pressure gradient barrier, causing the sealing medium pressure to continuously decrease when internal leakage occurs. This provides a clear pressure signal for leak detection, and the dynamic pressure change ensures the identifiability of the leak signal, improving the reliability of the synergy between sealing and detection.

[0060] The time-series synergistic analysis of voltage and pressure parameters reflects electrolyte mixing through abnormal voltage fluctuations and leakage of the sealing medium through continuous pressure decline. The joint judgment of the two parameters greatly improves the accuracy and sensitivity of internal leakage detection, avoids misjudgment caused by fluctuation of a single parameter, and solves the problem of difficulty in distinguishing between internal and external leakage.

[0061] According to one embodiment of the present invention, the airtightness detection method for a flow battery further includes: The single cell 100 that experienced abnormal voltage fluctuations was identified as the leak location.

[0062] In one embodiment of the present invention, after determining that there is an internal leak in the electrolyte, the airtightness detection method for the flow battery further determines the location of the leak: the voltage monitoring module assigns a unique identification number to each individual cell 100, and synchronously associates the corresponding identification number information when collecting voltage data, transmitting it to the system control center. The system control center compares and analyzes the voltage data of all individual cells 100 one by one, and filters out individual cells 100 with abnormal voltage fluctuations; the identification number of this individual cell 100 corresponds to the leak location. If the voltage of multiple individual cells 100 fluctuates abnormally at the same time, the system further accurately locates the individual cell 100 with the initial leak based on the timing of the pressure drop and the order of the voltage fluctuations, combined with the stacking position of the individual cells 100 and the connectivity of the gas chamber 106. The location result is displayed through the system interface and triggers a targeted warning.

[0063] The uniform pressure gradient formed by the dynamic air pressure sealing technology ensures that when internal leakage occurs, only the single cell 100 at the leakage location will experience electrolyte mixing, and the abnormal voltage fluctuations are clearly targeted, providing a basis for locating the leakage location. The dynamic maintenance of pressure ensures that the leakage signal does not spread, improving the accuracy of the location.

[0064] The independent numbering and dual-parameter collaborative analysis of the voltage monitoring module can directly pinpoint the leak location by identifying the single cell number 100 based on abnormal voltage fluctuations. This solves the problem of difficulty in determining the leak location within a multi-cell stack, significantly improving the efficiency and accuracy of leak location and providing a clear basis for rapid repair.

[0065] According to one embodiment of the present invention, the step of determining whether a fuel cell module has a leak includes: When the voltage of all individual cells 100 remains stable and the pressure of the sealing medium continues to drop, it is determined that electrolyte leakage has occurred.

[0066] In one embodiment of the present invention, the airtightness detection method for a flow battery determines electrolyte leakage according to the following process: a pressure control unit continuously supplies a sealing medium and maintains the pressure higher than the electrolyte pressure; a pressure sensor collects sealing medium pressure data in real time; a voltage monitoring module collects voltage data from all individual cells 100; and the data is synchronously transmitted to the system control center. The system control center performs stability analysis on the voltage data of all individual cells 100. If the variation range of all voltage data within a preset time period does not exceed the stable range, it is determined that the voltage remains stable. At the same time, a trend analysis is performed on the pressure data. If the pressure data decreases for several consecutive collection cycles without compensation and recovery, it is determined that the pressure is continuously decreasing. When both determination conditions are met simultaneously, the system control center automatically outputs the determination result of electrolyte leakage and triggers an external leakage warning signal, indicating that the external seal of the sealing system has failed.

[0067] The dynamic pressure sealing technology maintains a pressure gradient barrier, allowing the sealing medium to leak directly to the outside when an external leak occurs. The pressure continues to drop without electrolyte mixing, and the voltage remains stable. The dynamic changes in pressure provide a clear signal for external leak detection, improving the reliability of external leak detection.

[0068] The comparative analysis of voltage and pressure parameters, by stabilizing the voltage of all single cells at 100V to rule out the possibility of internal leakage, and confirming the sealing failure by continuously decreasing pressure, significantly improves the accuracy of external leakage detection, avoids misjudgment of external and internal leakage, and solves the defect that single pressure detection cannot distinguish the type of leakage.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hermetically sealed structure for a flow battery, characterized in that, include: A fuel cell stack module, the fuel cell stack module including at least one single cell (100), the single cell (100) containing an electrolyte; The single battery (100) is provided with an inner sealing strip (102) and an outer sealing strip (104), and a closed gas chamber (106) is defined between the inner sealing strip (102) and the outer sealing strip (104). A pressure control unit, which is connected to the gas chamber (106), is used to supply a sealing medium to the gas chamber (106) and maintain the pressure of the sealing medium higher than the pressure of the electrolyte to form a pressure gradient barrier. A voltage monitoring module for monitoring the voltage of at least one of the single cells (100).

2. The hermetic structure of the flow battery according to claim 1, characterized in that, The sealing medium is an inert gas.

3. The hermetic structure of the flow battery according to claim 1, characterized in that, The sealing medium is water.

4. The hermetic structure of the flow battery according to claim 3, characterized in that, It also includes a conductivity meter (108), the pressure control unit includes a loop for circulating water, and the conductivity meter (108) is disposed in the loop for monitoring the conductivity of the water.

5. The hermetic structure of the flow battery according to claim 1, characterized in that, The stack module includes multiple stacked single cells (100). The gas chambers (106) of the multiple single cells (100) are interconnected by gas channels to form a total sealed medium channel through the stack module.

6. The hermetic structure of the flow battery according to claim 1, characterized in that, The pressure control unit includes a sealing medium source (110), a pressure regulating valve (112), and a controller; The controller is used to control the opening of the pressure regulating valve (112) according to the monitored pressure of the sealing medium, so as to maintain the pressure of the sealing medium higher than the pressure of the electrolyte.

7. A method for detecting the airtightness of the airtight structure of a flow battery as described in any one of claims 1 to 6, characterized in that, include: The pressure control unit supplies a sealing medium to the gas chamber (106) and maintains the pressure of the sealing medium at a level higher than that of the electrolyte. The voltage of at least one of the single batteries (100) is monitored in real time using the voltage monitoring module. The pressure control unit monitors the pressure of the sealing medium in the gas chamber (106) in real time. Based on the monitored voltage changes of the single cell (100) and the pressure changes of the sealing medium, it is determined whether there is a leak in the fuel cell module.

8. The airtightness testing method for a flow battery according to claim 7, characterized in that, The step of determining whether the fuel cell module has a leak includes: When abnormal fluctuations in the voltage of the single cell (100) are detected, and the pressure of the sealing medium continues to drop, it is determined that an internal leakage of electrolyte has occurred.

9. The airtightness testing method for a flow battery according to claim 8, characterized in that, The airtightness testing method for the flow battery also includes: The single cell (100) experiencing abnormal voltage fluctuations was identified as the leak location.

10. The airtightness testing method for a flow battery according to claim 7, characterized in that, The step of determining whether the fuel cell module has a leak includes: When the voltage of all individual cells (100) remains stable and the pressure of the sealing medium continues to decrease, it is determined that electrolyte leakage has occurred.

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