A bromine leak warning system and method for zinc-bromine flow batteries

Abstract

This invention belongs to the field of electrochemical energy storage safety technology and discloses a bromine leakage early warning system and method for zinc-bromine flow batteries. The system includes a negative pressure sealed chamber, a micro-pressure differential monitoring unit, and an early warning control unit. The negative pressure sealed chamber is a hollow sealed chamber structure used to provide a sealed micro-negative pressure space for key components in the target battery that are prone to bromine leakage. The micro-pressure differential monitoring unit is used to monitor the pressure difference between the inside of the negative pressure sealed chamber and the external atmospheric pressure in real time. The early warning control unit is electrically connected to the micro-pressure differential monitoring unit and is used to receive the pressure difference data, determine whether bromine leakage has occurred based on preset pressure change criteria, and generate a leakage early warning signal or linkage control command. This invention indirectly and proactively determines bromine leakage events by monitoring the internal pressure changes of the negative pressure sealed chamber, without the need for monitoring bromine gas. It has the advantages of simple structure, rapid response, high reliability, and low cost.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical energy storage safety technology, and specifically relates to a bromine leakage early warning system and method for zinc-bromine flow batteries. Background Technology

[0002] With the rapid development of the new energy industry, large-scale energy storage technology has become a key support for the efficient utilization of renewable energy (such as solar and wind power). Among them, zinc-bromine flow batteries are one of the most promising large-scale energy storage technologies due to their moderate energy density, relatively low cost, and long cycle life.

[0003] The core working principle of a zinc-bromine flow battery is to store and release electrical energy through the redox reaction of zinc and bromide ions in the electrolyte. The electrolyte is mainly composed of zinc salts, bromide salts, and elemental bromine and polybrominates as active materials. In practical applications of zinc-bromine flow batteries, the elemental bromine and polybrominates in the electrolyte are highly corrosive and toxic. If the battery compartment seal fails, the pipeline is damaged, or the joint is loose, electrolyte leakage will occur, causing elemental bromine and polybrominates to come into direct contact with equipment components, resulting in corrosion damage. At the same time, they may volatilize to form bromine vapor, causing pollution and safety problems to the surrounding environment.

[0004] Currently, common bromine leak detection methods mainly rely on bromine gas concentration sensors installed inside the battery compartment. These sensors monitor the concentration of bromine vapor in real time, triggering an alarm when the concentration reaches a preset threshold, thus alerting personnel to address the leak promptly. However, this method generally suffers from delayed early warning response, high maintenance costs, and an inability to provide early warning for minor leaks, thus failing to meet the safety requirements for large-scale applications of zinc-bromine flow batteries. Specifically, existing monitoring methods rely on bromine gas concentration sensors to capture the volatilized bromine vapor after a leak, requiring the bromine vapor to diffuse to the sensor probe before triggering an alarm, resulting in a significant delay in early warning response. Secondly, bromine vapor can poison or corrode the sensor probe, leading to decreased sensitivity or even failure, resulting in low reliability and high maintenance costs. Furthermore, multi-point sensor deployment systems are complex, expensive, and unable to provide early warning for minor leaks. Therefore, there is an urgent need for a faster, more reliable, simpler, and lower-cost bromine leak early warning solution. Summary of the Invention

[0005] To address the technical problems existing in the prior art, this invention provides a bromine leakage early warning system and method for zinc-bromine flow batteries, which solves the technical problems that monitoring methods generally suffer from delayed early warning response, high maintenance costs, and inability to meet the requirements for early warning of minute leaks.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention provides a bromine leakage early warning system for zinc-bromine flow batteries, comprising a negative pressure sealed chamber, a micro-pressure differential monitoring unit, and an early warning control unit; The negative pressure sealed chamber is a hollow sealed chamber structure used to provide a sealed micro-negative pressure space for key components in the target battery that are prone to bromine leakage. The micro-pressure differential monitoring unit is used to monitor the pressure difference between the inside of the negative pressure sealed chamber and the external atmospheric pressure in real time. The early warning control unit is electrically connected to the micro differential pressure monitoring unit, and is used to receive pressure difference data, determine whether bromine leakage has occurred according to the preset pressure change criteria, and generate a leakage early warning signal or linkage control command; wherein, the linkage control command is used to trigger the target battery to perform an emergency shutdown action.

[0007] Furthermore, the key components in the target battery that are prone to bromine leakage include the battery stack, electrolyte circulation pipeline, pump and valve assembly, or storage tank.

[0008] Furthermore, the micro-differential pressure monitoring unit employs a micro-differential pressure sensor; wherein, the high-pressure side measuring port of the micro-differential pressure sensor is connected to the interior of the negative pressure sealed chamber, and the low-pressure side measuring port of the micro-differential pressure sensor is connected to the outside atmosphere.

[0009] Furthermore, it also includes a pressure regulating device, which is connected to the negative pressure sealed chamber; wherein the pressure regulating device is used to establish and maintain a micro-negative pressure state inside the negative pressure sealed chamber.

[0010] Furthermore, the pressure regulating device employs an induced draft fan or a normally open exhaust valve.

[0011] Furthermore, the early warning control unit includes a data processing module, a leakage detection module, and an early warning execution module; The data processing module is used to filter and calculate the received pressure difference data to obtain the real-time pressure difference value and the rate of change of pressure difference. The leakage detection module is used to compare the real-time pressure difference or the rate of change of pressure difference with a preset pressure change criterion to obtain a pressure change comparison result. The early warning execution module is used to determine whether a bromine leak has occurred based on the pressure change comparison results, and to generate a leak warning signal or linkage control command.

[0012] Furthermore, the preset pressure change criteria include preset early warning thresholds and preset alarm linkage thresholds; The preset warning threshold is set based on the rate of change of pressure difference inside the negative pressure sealed chamber during normal operation of the zinc-bromine flow battery. The preset alarm linkage threshold is set based on the absolute pressure value inside the negative pressure sealed chamber during normal operation of the zinc-bromine flow battery.

[0013] Furthermore, the preset alarm linkage threshold is the pressure difference corresponding to the pressure difference between the inside of the negative pressure sealed chamber and the external atmospheric pressure.

[0014] The present invention also provides a bromine leakage early warning method for zinc-bromine flow batteries, utilizing the aforementioned bromine leakage early warning system for zinc-bromine flow batteries; The bromine leakage early warning method for zinc-bromine flow batteries includes: Real-time monitoring of the pressure difference between the inside of the negative pressure sealed chamber and the external atmospheric pressure; Based on pressure difference data and according to preset pressure change criteria, it determines whether bromine leakage has occurred and generates a leakage warning signal or linkage control command; among which, the linkage control command is used to trigger the target battery to perform an emergency shutdown action.

[0015] Furthermore, the preset pressure change criteria include preset early warning thresholds and preset alarm linkage thresholds; The preset warning threshold is set based on the rate of change of pressure difference inside the negative pressure sealed chamber during normal operation of the zinc-bromine flow battery. The preset alarm linkage threshold is set based on the absolute pressure value inside the negative pressure sealed chamber during normal operation of the zinc-bromine flow battery.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: The bromine leak warning system for zinc-bromine flow batteries provided by this invention indirectly and proactively detects bromine leaks by monitoring changes in the internal pressure of a negative pressure sealed chamber. This eliminates the need to monitor the leaking bromine gas, offering advantages such as simple structure, rapid response, high reliability, and low cost. Specifically, by setting up a negative pressure sealed chamber, key components in the zinc-bromine flow battery prone to bromine leaks are enclosed within a slightly negative pressure space. A micro-pressure difference monitoring unit captures real-time changes in the pressure difference between the inside of the negative pressure sealed chamber and the external atmospheric pressure, and combines this with preset criteria from the warning control unit to achieve leak detection and warning. Compared to existing monitoring methods that rely on bromine gas concentration sensors, this system does not need to wait for bromine vapor to diffuse to the sensor probe after a leak; instead, it can detect minute leaks through minute changes in the slightly negative pressure state of the chamber, completely solving the problem of delayed warning response. Furthermore, since the monitored object is the pressure difference, it avoids the poisoning and corrosion of the sensor probe by bromine vapor, significantly improving monitoring reliability, reducing maintenance costs, and eliminating the need for multiple sensor placements. This results in a simpler system structure and lower cost, effectively meeting the safety warning requirements for large-scale applications of zinc-bromine flow batteries.

[0017] The bromine leakage early warning method for zinc-bromine flow batteries provided by this invention possesses all the advantages of the aforementioned bromine leakage early warning system for zinc-bromine flow batteries. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A perspective view of the bromine leak warning system for a zinc-bromine flow battery provided in Example 1; Figure 2 This is a structural block diagram of the bromine leakage early warning system for a zinc-bromine flow battery provided in Example 1; Figure 3 The flowchart is for the bromine leakage early warning method for zinc-bromine flow batteries provided in Example 2.

[0020] The components include: 1. Negative pressure sealed chamber; 2. Micro-pressure differential monitoring unit; 3. Early warning control unit; 4. Pressure regulating device; 100. Key components in the target battery that are prone to bromine leakage; 31. Data processing module; 32. Leakage judgment module; 33. Early warning execution module. Detailed Implementation

[0021] To make the technical problems, technical solutions, and beneficial effects solved by this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0022] Before describing the specific embodiments of this application, some of the technical terms involved in the embodiments of this application are explained as follows: Micro-negative pressure refers to a negative pressure state where the pressure value is slightly lower than the external atmospheric pressure and the pressure fluctuation is within a preset stable range. Its negative pressure difference is small, which can achieve sealing protection while avoiding damage to the key components of the target battery due to excessive negative pressure, and is suitable for the operating conditions of zinc-bromine flow batteries.

[0023] Slight positive pressure refers to a positive pressure state where the pressure value is slightly higher than the external atmospheric pressure and the pressure fluctuation is within a preset safe range. Its positive pressure difference is small and mainly occurs in scenarios where bromine leakage intensifies, leading to the failure of negative pressure sealing chambers. It serves as a key indicator for judging the severity of leakage.

[0024] The present invention provides a bromine leakage early warning system for zinc-bromine flow batteries, comprising a negative pressure sealed chamber 1, a micro-pressure differential monitoring unit 2, and an early warning control unit 3.

[0025] The negative pressure sealed chamber 1 is a hollow sealed chamber structure used to provide a sealed micro-negative pressure space for the key component 100 in the target battery that is prone to bromine leakage.

[0026] The micro-pressure difference monitoring unit 2 is used to monitor the pressure difference data between the inside of the negative pressure sealed chamber 1 and the external atmospheric pressure in real time.

[0027] The early warning control unit 3 is electrically connected to the micro pressure difference monitoring unit 2, and is used to receive pressure difference data, determine whether bromine leakage has occurred according to the preset pressure change criteria, and generate a leakage early warning signal or linkage control command; wherein, the linkage control command is used to trigger the target battery to perform an emergency shutdown action.

[0028] Optionally, it also includes a pressure regulating device 4, which is connected to the negative pressure sealed chamber 1; wherein, the pressure regulating device 4 is used to establish and maintain a micro-negative pressure state inside the negative pressure sealed chamber 1.

[0029] In the above embodiments, by monitoring the internal pressure changes of the negative pressure sealed chamber 1, the traditional passive monitoring mode of detecting bromine vapor after leakage is transformed into an active early warning mechanism that captures pressure anomalies before leakage, so as to indirectly and proactively determine bromine leakage events without monitoring the leaked bromine gas.

[0030] Specifically, the negative pressure sealed chamber 1 maintains a stable negative pressure state during normal operation. Once the seal fails or the pipeline is damaged, external air will rush in instantly instead of bromine vapor escaping. The pressure difference change propagates at the speed of sound waves, and the micro-pressure difference monitoring unit 2 can capture pressure fluctuations in milliseconds, completely eliminating the waiting time for bromine vapor to diffuse to the sensor probe and realizing immediate early warning of leakage. Secondly, the micro-pressure difference monitoring unit 2 only senses pressure changes and does not need to directly contact corrosive bromine vapor, fundamentally avoiding the problem of probe poisoning failure, significantly improving system reliability and greatly extending the maintenance cycle. Furthermore, the single-point micro-pressure difference monitoring unit 2 can cover the integrity of the entire negative pressure sealed chamber 1, eliminating the need for multiple bromine gas sensors, significantly reducing hardware costs and system complexity. At the same time, the micro-negative pressure environment itself constitutes a physical barrier against bromine leakage, and even if damage occurs, it can suppress the escape of bromine vapor, taking into account the dual functions of monitoring and early warning and safety protection. Thus, with a minimalist architecture, it achieves early detection and rapid response to minor leaks, effectively meeting the safety requirements of large-scale deployment of zinc-bromine flow batteries.

[0031] The following specific embodiments further illustrate the bromine leakage early warning system for zinc-bromine flow batteries provided by the present invention: Example 1 As attached Figure 1-2 As shown, this embodiment 1 provides a bromine leakage early warning system for a zinc-bromine flow battery, including a negative pressure sealed chamber 1, a micro-pressure differential monitoring unit 2, and an early warning control unit 3; a key component 100 in the target battery that is prone to bromine leakage is disposed inside the negative pressure sealed chamber 1; the micro-pressure differential monitoring unit 2 is installed on the negative pressure sealed chamber 1, and the output terminal of the micro-pressure differential monitoring unit 2 is connected to the input terminal of the early warning control unit 3.

[0032] The negative pressure sealed chamber 1 is a hollow sealed chamber structure, used to provide a sealed micro-negative pressure space for the key component 100 in the target battery that is prone to bromine leakage, so as to seal the key component 100 in the target battery that is prone to bromine leakage entirely in its internal space.

[0033] Optionally, the key component 100 in the target battery that is prone to bromine leakage includes a battery stack, an electrolyte circulation pipeline, a pump and valve assembly, or a storage tank. It should be noted that the battery stack is the core area of ​​the electrolyte reaction, the electrolyte circulation pipeline is the electrolyte delivery channel, the pump and valve assembly is the weakest link in the seal, and the storage tank is the core of electrolyte storage. In this embodiment 1, the key component 100 in the target battery that is prone to bromine leakage is set to include a battery stack, an electrolyte circulation pipeline, a pump and valve assembly, or a storage tank. This allows the negative pressure sealing chamber 1 to be precisely focused on high-risk areas without the need to seal the entire battery compartment, significantly reducing the design, manufacturing, and installation costs of the sealing chamber. At the same time, precise coverage of key components ensures that the micro-differential pressure monitoring unit 2 can more directly and quickly capture pressure changes caused by leakage, further improving the early warning sensitivity of small leaks and avoiding warning delays caused by excessively large monitoring ranges. This specifically solves the shortcomings of existing monitoring schemes, such as system complexity, high cost, and insufficient warning targeting.

[0034] Preferably, the negative pressure sealed chamber 1 is made of a bromine-resistant material; wherein, the bromine-resistant material is, for example, polypropylene (PP), polyvinylidene fluoride (PVDF) or fiberglass, and is designed to encapsulate the easily leaking core components of the zinc-bromine flow battery as a whole, forming an independent space with good airtightness.

[0035] Explanatory, the micro-negative pressure space refers to a sealed space provided for key components in zinc-bromine flow batteries that are prone to bromine leakage. The internal pressure is slightly lower than the external atmospheric pressure, and the pressure fluctuation is within a preset stable range. Its core function is to achieve sealed protection for key components. It can quickly generate identifiable pressure changes when a small bromine leak occurs, providing conditions for early warning, and can also avoid damage to key components of the target battery due to excessive negative pressure, adapting to the actual operating conditions of zinc-bromine flow batteries.

[0036] The micro-pressure differential monitoring unit 2 is used to monitor the pressure difference data between the inside of the negative pressure sealed chamber 1 and the external atmospheric pressure in real time; optionally, the micro-pressure differential monitoring unit 2 adopts a micro-pressure differential sensor; wherein, the high-pressure side measuring port of the micro-pressure differential sensor is connected to the inside of the negative pressure sealed chamber 1, and the low-pressure side measuring port of the micro-pressure differential sensor is connected to the outside atmosphere.

[0037] It should be noted that by directly connecting the high-pressure side of the micro differential pressure sensor to the interior of the negative pressure sealed chamber 1, while the low-pressure side is connected to the external atmosphere, the pressure difference between the inside and outside of the negative pressure sealed chamber can be measured in real time and continuously without contact with bromine vapor. This fundamentally avoids the poisoning and corrosion problems of bromine vapor on the sensor probe, significantly improving the reliability and service life of the micro differential pressure monitoring unit 2 and reducing maintenance costs. At the same time, it ensures that the acquisition of pressure difference data is not affected by irrelevant external factors, resulting in higher measurement accuracy. It can capture subtle pressure changes caused by minute leaks, further optimizing the early warning effect and solving the technical problems of low reliability, high maintenance costs, and insufficient accuracy in detecting minute leaks in existing sensors. Preferably, the accuracy of the micro differential pressure sensor is ±0.5%FS.

[0038] The early warning control unit 3 is used to receive pressure difference data, determine whether bromine leakage has occurred based on preset pressure change criteria, and generate a leakage early warning signal or linkage control command; specifically, the early warning control unit 3 includes a data processing module 31, a leakage judgment module 32, and an early warning execution module 33.

[0039] The data processing module 31 is used to filter and calculate the received pressure difference data to obtain the real-time pressure difference value and the rate of change of pressure difference; optionally, the process of filtering and calculating the received pressure difference data is as follows: First, a moving average filtering algorithm is used to filter the pressure difference data collected in real time by the micro-pressure difference monitoring unit 2 to obtain filtered pressure difference data. The length of the preset sliding window is set, and the arithmetic mean of the original pressure difference data within the window is taken to eliminate abnormal data points caused by external instantaneous interference or small fluctuations of the sensor. Preferably, the length of the preset sliding window is 5-10 sampling periods.

[0040] Next, calculations are performed based on the filtered pressure difference data to obtain the real-time pressure difference value and the rate of change of pressure difference. The real-time pressure difference value is the pressure difference data corresponding to the current sampling period after filtering. The rate of change of pressure difference is calculated from the filtered pressure difference data of two adjacent sampling periods. The calculation process for the rate of change of pressure difference is as follows:

[0041] in, The rate of change of pressure difference; This is the filtered pressure difference data for the current sampling period; This is the filtered pressure difference data from the previous sampling period; This is the time interval between two adjacent sampling periods.

[0042] The leakage judgment module 32 is used to compare the real-time pressure difference or the rate of change of pressure difference with a preset pressure change criterion to obtain a pressure change comparison result; wherein, the preset pressure change criterion includes a preset early warning threshold and a preset alarm linkage threshold.

[0043] Specifically, the process of comparing the real-time pressure difference or the rate of change of pressure difference with a preset pressure change criterion includes: comparing the rate of change of pressure difference with a preset warning threshold; and comparing the real-time pressure difference with a preset alarm linkage threshold.

[0044] Optionally, the preset warning threshold is set based on the rate of change of pressure difference inside the negative pressure sealed chamber 1 during normal operation of the zinc-bromine flow battery; the preset alarm linkage threshold is set based on the absolute pressure value inside the negative pressure sealed chamber 1 during normal operation of the zinc-bromine flow battery; preferably, the preset alarm linkage threshold is the pressure difference value corresponding to the pressure inside the negative pressure sealed chamber 1 being equal to the external atmospheric pressure; for example, the preset alarm linkage threshold is 0 Pa, which means that the pressure inside the negative pressure sealed chamber 1 rises from negative pressure to the external atmospheric pressure or slightly positive pressure.

[0045] The system employs a dual pressure change criterion system, employing preset warning thresholds and preset alarm linkage thresholds. Both criteria are based on chamber pressure parameters during normal battery operation, ensuring the rationality and relevance of the judgments to actual operating conditions. The warning threshold, set based on the rate of pressure change, can detect minor leaks in their early stages, before significant absolute changes in chamber pressure, by observing abnormal pressure change rates, thus addressing the core deficiency of delayed warnings in existing solutions. The alarm linkage threshold, set based on absolute pressure values, can promptly trigger higher-level alarms and linkage controls when the leak worsens or chamber pressure abnormally rises, enabling tiered handling of leaks. This avoids missed detections of minor leaks and prevents equipment damage and environmental pollution caused by untimely handling of serious leaks, further enhancing the scientific rigor and safety of the monitoring system's warning mechanism.

[0046] The early warning execution module 33 is used to determine whether a bromine leak has occurred based on the pressure change comparison results, and to generate a leak early warning signal or a linkage control command; wherein, the linkage control command is used to trigger the target battery to perform an emergency shutdown action.

[0047] The specific implementation process is as follows: If the pressure change comparison result is: the rate of change of pressure difference is greater than or equal to the preset warning threshold, but the real-time pressure difference is less than the preset alarm linkage threshold, then it is determined that there is a potential leakage risk and a first-level warning signal is generated.

[0048] If the pressure change comparison result is: the rate of change of pressure difference is greater than or equal to the preset warning threshold, and the real-time pressure difference is greater than or equal to the preset alarm linkage threshold, then a leakage risk is determined, a secondary warning signal is generated, and a linkage control command is generated and sent to the battery management system (BMS) of the target battery to trigger the battery management system to perform an emergency shutdown operation.

[0049] The system includes an explanatory first-level warning signal for early indication of decreased sealing performance or minor leaks; a second-level warning signal and linkage control command for confirming serious leaks and triggering an emergency response; optionally, the warning control unit 3 further includes an audible and visual alarm module connected to the warning execution module 33 for responding to the first-level or second-level warning signal with sound or light signals.

[0050] It is worth noting that the early warning control unit 3 is divided into three functional modules: a data processing module 31, a leak judgment module 32, and an early warning execution module 33. This modular division of labor for monitoring data processing, leak judgment, and early warning execution improves the operational stability and maintainability of the early warning control unit 3. Specifically, the filtering process of the data processing module 31 can eliminate interference signals in the pressure difference data, ensuring data accuracy. The calculation of the pressure difference change rate can capture the pressure change trend in the early stage of leakage, providing data support for early warning. The leak judgment module 32 can accurately distinguish between normal pressure fluctuations and pressure changes caused by bromine leakage through multi-parameter comparison, reducing the probability of misjudgment. The early warning execution module 33 can generate different early warning signals or linkage control commands based on the judgment results, realizing graded early warning and emergency response. This solves the defects of low early warning accuracy and inability to achieve graded response in existing monitoring schemes, further improving the practicality and safety of the monitoring system.

[0051] Secondly, the alarm linkage threshold is set to the pressure difference between the internal pressure of the negative pressure sealed chamber 1 and the external atmospheric pressure, which represents the pressure difference when the internal pressure of the negative pressure sealed chamber 1 rises to the external atmospheric pressure or a preset slight positive pressure. This aligns with the actual evolution of bromine leakage. When a bromine leak occurs and the leakage is significant, outside air will be drawn in due to the negative pressure of the chamber. Simultaneously, the evaporation of the leaked electrolyte will cause the chamber pressure to gradually rise until it reaches the external atmospheric pressure or even a slight positive pressure. At this point, the leak is quite serious, and emergency response must be triggered immediately. This threshold setting accurately corresponds to the severity of the leak, ensuring timely triggering of linkage control commands. It avoids unnecessary emergency shutdowns that could affect normal battery operation and allows for rapid response when the leak worsens, preventing large-scale bromine vapor evaporation from polluting the environment and corroding equipment. This solves the problems of inaccurate linkage control triggering and the inability to balance operational stability and safety protection in existing monitoring solutions.

[0052] Furthermore, the alarm linkage threshold is set to the pressure difference between the internal pressure of the negative pressure sealed chamber 1 and the external atmospheric pressure. In this case, the alarm linkage threshold can be set to 0 Pa, which facilitates accurate setting and calibration, reducing the debugging difficulty of the monitoring system. At the same time, 0 Pa serves as the dividing point between negative and positive pressure, clearly distinguishing the severity of the leak. Specifically, when the chamber pressure drops from negative pressure to below 0 Pa, it is in a normal slightly negative pressure state. When the pressure rises back to 0 Pa or above, it indicates that the leak has caused the chamber's negative pressure to fail, and there is a significant risk of bromine vapor volatilization. At this point, triggering emergency shutdown and other linkage controls can quickly cut off the leak source and minimize the losses caused by the leak. This specific numerical setting makes the triggering standard of linkage control clearer and more uniform, improving the versatility and accuracy of the monitoring system, avoiding the problem of untimely or false linkage caused by ambiguous thresholds, and further adapting to the standardization requirements of large-scale application of zinc-bromine flow batteries.

[0053] This embodiment 1 also provides another implementation method, specifically: The bromine leakage early warning system for zinc-bromine flow batteries further includes a pressure regulating device 4; the pressure regulating device 4 is connected to the negative pressure sealed chamber 1, and the pressure regulating device 4 is used to establish and maintain a micro-negative pressure state inside the negative pressure sealed chamber 1; preferably, the pressure value of the micro-negative pressure state is -30Pa to -100Pa.

[0054] Explained, by setting up the pressure regulating device 4, a micro-negative pressure state can be actively established and stably maintained inside the negative pressure sealed chamber 1, ensuring that the internal pressure of the chamber is always within the preset stable range, eliminating the interference of the external environment and battery operating conditions on the chamber pressure, ensuring the stability and accuracy of the data collected by the micro-pressure differential monitoring unit 2, and avoiding false alarms or missed alarms; at the same time, the stable micro-negative pressure environment allows the chamber pressure to quickly produce a identifiable change when a minor leak occurs, further improving the response speed of early warning, and specifically solving the defects of insufficient early warning reliability and susceptibility to external interference in existing monitoring schemes, providing a stable pressure basis for the accurate monitoring of bromine leaks.

[0055] Optionally, the pressure regulating device 4 adopts an induced draft fan or a normally open exhaust valve. In this embodiment 1, the pressure regulating device 4 adopts an induced draft fan or a normally open exhaust valve, which can actively maintain a stable micro-negative pressure state inside the chamber during normal system operation. This ensures that in the event of any leakage, external air will first be drawn into the interior of the negative pressure sealed chamber 1, causing a change in pressure characteristics, which can then be monitored. It should be noted that the induced draft fan and normally open exhaust valve have the characteristics of simple structure, low manufacturing cost, convenient installation, and low maintenance workload, which can effectively control the cost of the entire monitoring system and meet the needs of large-scale application of zinc-bromine flow batteries. Among them, the induced draft fan can actively adjust the negative pressure of the chamber to adapt to the sealing and protection requirements under different working conditions and ensure the stability of the negative pressure state. The normally open exhaust valve can achieve passive exhaust and pressure stabilization, with a simpler structure, requiring no additional power, further reducing energy consumption and maintenance costs.

[0056] Working principle: The bromine leakage early warning system for zinc-bromine flow batteries described in Example 1 operates on the following principle: The critical components most prone to bromine leakage in the zinc-bromine flow battery, such as the battery stack, electrolyte circulation pipeline, pump valve assembly, or storage tank, are encapsulated in a negative pressure sealed chamber supported by bromine corrosion-resistant material. Airflow between the inside and outside of the negative pressure sealed chamber is strictly restricted. Air is actively and slowly expelled from the chamber via a pressure regulating device (such as an induced draft fan or a normally open exhaust valve), maintaining a stable micro-negative pressure state where the internal pressure is slightly lower than the external atmospheric pressure. Preferably, the internal pressure of the chamber is maintained at -50 Pa.

[0057] When there is no bromine leakage, the chamber is well sealed, and the pressure regulating device maintains the internal pressure at a preset negative pressure value. The micro-pressure differential monitoring unit continuously reads a stable negative pressure value. When any bromine or electrolyte leak occurs in the battery components inside the chamber (whether it is a slow seepage or a rapid spray), the leak point is equivalent to opening an additional air inlet on the chamber. Since the chamber is under negative pressure, outside air will be immediately and rapidly drawn into the chamber through this additional air inlet (i.e., the leak point), which will directly cause the pressure inside the chamber to rise rapidly and tend to balance with the external atmospheric pressure.

[0058] The early warning control unit analyzes the micro-pressure difference monitoring unit in real time and performs graded judgments based on preset pressure change criteria. When the rate of change of the monitored pressure difference exceeds the preset early warning threshold, for example, if the pressure difference rises rapidly from -50Pa to -30Pa within 10 seconds, it indicates that a trace amount of gas is continuously entering. This indicates that there may be slow leakage or very small leakage caused by aging of the seals, triggering a first-level early warning signal (such as flashing yellow light on the control panel or software pop-up). At this time, bromine may not have actually leaked or the concentration may be extremely low, but maintenance personnel have received the inspection prompt and can arrange preventive maintenance. If the bromine leak is significant and a large amount of external air is drawn in, the pressure inside the chamber will continue to rise until it reaches the same level as the ambient atmospheric pressure (0 Pa) or even turns into a slightly positive pressure. That is, if the real-time pressure difference is greater than or equal to the preset alarm linkage threshold, a serious leak is confirmed. At this time, bromine vapor may have already begun to escape from the leak point, which will immediately trigger a secondary alarm signal (such as a high-frequency audible and visual alarm) and simultaneously send an emergency shutdown linkage control command to the battery management system. After receiving the linkage control command, the battery management system will immediately stop the electrolyte circulation pump and close the relevant valves to physically cut off the leak source and prevent the accident from escalating.

[0059] The bromine leakage early warning system for zinc-bromine flow batteries described in Example 1 indirectly and proactively determines leakage events by monitoring changes in the pressure of the sealed chamber. It does not require direct monitoring of bromine gas and has the advantages of simple structure, rapid response, high reliability, and low cost.

[0060] Example 2 This embodiment 2 provides a bromine leakage early warning method for zinc-bromine flow batteries, utilizing the bromine leakage early warning system for zinc-bromine flow batteries described in embodiment 1 above; as shown in the attached... Figure 3 As shown, a bromine leakage early warning method for zinc-bromine flow batteries includes the following steps: Step S1: Use the pressure regulating device 4 to regulate and maintain the pressure of the negative pressure sealed chamber 1, so that a slight negative pressure state is formed and maintained inside the negative pressure sealed chamber 1. Preferably, the pressure value of the slight negative pressure state is -30Pa to -100Pa.

[0061] Step S2: The pressure difference data inside and outside the negative pressure sealed chamber 1 is continuously and in real time collected by the micro pressure difference monitoring unit 2, and the pressure difference data is sent to the early warning control unit 3.

[0062] Step S3: The early warning control unit 3 receives the pressure difference data collected in real time by the micro pressure difference monitoring unit 2, and determines whether bromine leakage has occurred based on the preset pressure change criteria, and generates a leakage early warning signal or linkage control command.

[0063] The specific implementation process is as follows: The data processing module 31 is used to filter and calculate the received pressure difference data to obtain the real-time pressure difference value and the rate of change of pressure difference. The leakage judgment module 32 is used to compare the real-time pressure difference value or the rate of change of pressure difference with the preset pressure change criterion to obtain the pressure change comparison result. The early warning execution module 33 is used to determine whether bromine leakage has occurred based on the pressure change comparison result, and to generate a leakage early warning signal or linkage control command.

[0064] Explanatoryly, if the rate of pressure change exceeds the preset warning threshold, a potential leakage risk is determined, and a first-level warning signal is generated; if the real-time pressure difference exceeds the preset alarm linkage threshold, indicating that the pressure inside the chamber has risen back to atmospheric pressure or above, a leakage risk is determined, a second-level warning signal is generated and issued, and a linkage control command is sent to the battery management system (BMS) to trigger an emergency shutdown, such as stopping the circulation pump or closing valve operations, to curb the leakage at the source.

[0065] Engineering example illustration: In this engineering example, a 5kW zinc-bromine flow battery module is used as an example to illustrate the bromine leakage early warning system described in this invention.

[0066] In this project example, the negative pressure sealed chamber is integrally molded from 8mm thick PP board, completely enclosing the 5kW zinc-bromine flow battery module stack and all external circulation pipelines and valves inside the negative pressure sealed chamber; the negative pressure sealed chamber has observation windows and wire sealing joints; the micro differential pressure sensor has a range of ±500Pa and an accuracy of ±0.5%FS, and is installed on the chamber wall of the negative pressure sealed chamber; the high-pressure side measuring port of the micro differential pressure sensor is connected to the middle of the chamber through an air pipe, while the low-pressure side measuring port is connected to the external ambient atmosphere.

[0067] The signal from the differential pressure sensor is connected to the early warning control unit; the early warning control unit adopts an industrial PLC.

[0068] A DC centrifugal induced draft fan is used as a pressure regulating device and is installed at the exhaust port on the top of the chamber. After the system is started, the speed of the induced draft fan is adjusted to keep the internal pressure of the negative pressure sealed chamber stable at -50Pa.

[0069] The early warning control unit has preset early warning thresholds and alarm linkage thresholds as preset pressure change criteria. When the rate of change of pressure difference is greater than the preset early warning threshold and lasts for 10 seconds, it is determined that there is a potential leakage risk and generates a first-level early warning signal, such as a flashing yellow indicator light. When the real-time pressure difference in the cabin is detected to be greater than or equal to 0 Pa, it is determined to be a second-level alarm, which drives the on-site audible and visual alarm to sound. At the same time, a passive closing signal is sent to the battery BMS through the relay dry contact. After receiving this signal, the BMS executes the emergency shutdown procedure.

[0070] Simulated testing process: In this project example, a simulated leak test was conducted on the system. The test results showed that when a tiny leak was artificially created inside the chamber, the system triggered a first-level warning within 3 seconds. When the leak expanded, the pressure rose back to 0 Pa within 8 seconds, triggering a second-level alarm and shutdown linkage. The entire process of warning and preliminary handling was completed before the bromine vapor concentration reached the alarm threshold of traditional sensors, fully demonstrating its advanced nature and reliability.

[0071] The bromine leakage early warning system and method for zinc-bromine flow batteries described in this invention indirectly and proactively determines the leakage event by monitoring changes in the pressure of the sealed chamber, without the need for direct detection of bromine gas. It has the advantages of simple structure, rapid response, high reliability, and low cost. In particular, by directly monitoring the physical pressure changes caused by the leakage, the response speed reaches the second level, which is much faster than sensors that rely on gas diffusion, thereby achieving ultra-early warning and featuring advanced response and high sensitivity.

[0072] This invention employs physical pressure monitoring, avoiding the problems of chemical sensors being susceptible to poisoning, drift, and failure. It operates stably and requires almost no maintenance. The entire system consists of only a negative pressure sealed chamber, a micro-pressure differential monitoring unit, and an early warning control unit. The hardware cost and maintenance complexity are far lower than those of multi-point gas detection systems. By using dual criteria of pressure difference change rate and real-time pressure difference value, it effectively distinguishes between normal fluctuations and actual leaks, virtually eliminating false alarms. Once a leak is confirmed, it can automatically interlock and shut down, achieving closed-loop safety control from monitoring to handling, thus improving the inherent safety level of the system.

[0073] The above embodiments are merely one of the implementation methods for achieving the technical solution of the present invention. The scope of protection claimed by the present invention is not limited to this embodiment, but also includes any variations, substitutions and other implementation methods that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention.

Claims

1. A bromine leak early warning system for a zinc-bromine flow battery, characterized in that, It includes a negative pressure sealed chamber (1), a micro pressure difference monitoring unit (2), and an early warning control unit (3); The negative pressure sealed chamber (1) is a hollow sealed chamber structure used to provide a closed micro negative pressure space for the key component (100) in the target battery that is prone to bromine leakage; The micro-pressure difference monitoring unit (2) is used to monitor the pressure difference data between the inside of the negative pressure sealed chamber (1) and the external atmospheric pressure in real time; The early warning control unit (3) is electrically connected to the micro pressure difference monitoring unit (2) and is used to receive pressure difference data, determine whether bromine leakage has occurred according to the preset pressure change criteria, and generate a leakage early warning signal or linkage control command; wherein, the linkage control command is used to trigger the target battery to perform an emergency shutdown action.

2. A bromine leak early warning system for a zinc-bromine flow battery according to claim 1, wherein, The key components (100) in the target battery that are prone to bromine leakage include the battery stack, electrolyte circulation pipeline, pump and valve assembly or storage tank.

3. A bromine leak early warning system for a zinc-bromine flow battery according to claim 1, wherein, The micro differential pressure monitoring unit (2) uses a micro differential pressure sensor; wherein, the high-pressure side measuring port of the micro differential pressure sensor is connected to the interior of the negative pressure sealed chamber (1), and the low-pressure side measuring port of the micro differential pressure sensor is connected to the outside atmosphere.

4. The bromine leak early warning system for a zinc-bromine flow battery of claim 1, wherein, It also includes a pressure regulating device (4), which is connected to the negative pressure sealed chamber (1); wherein the pressure regulating device (4) is used to establish and maintain a micro negative pressure state inside the negative pressure sealed chamber (1).

5. A bromine leakage early warning system for a zinc-bromine flow battery according to claim 1, characterized in that, The pressure regulating device (4) adopts an induced draft fan or a normally open exhaust valve.

6. A bromine leakage early warning system for a zinc-bromine flow battery according to claim 1, characterized in that, The early warning control unit (3) includes a data processing module (31), a leakage judgment module (32), and an early warning execution module (33). The data processing module (31) is used to filter and calculate the received pressure difference data to obtain the real-time pressure difference value and the rate of change of pressure difference. The leakage judgment module (32) is used to compare the real-time pressure difference or pressure difference change rate with the preset pressure change criterion to obtain the pressure change comparison result; The early warning execution module (33) is used to determine whether a bromine leak has occurred based on the pressure change comparison results, and to generate a leak warning signal or linkage control command.

7. A bromine leakage early warning system for a zinc-bromine flow battery according to claim 1, characterized in that, The preset pressure change criteria include preset warning thresholds and preset alarm linkage thresholds; The preset warning threshold is set based on the rate of change of pressure difference inside the negative pressure sealed chamber (1) during normal operation of the zinc-bromine flow battery. The preset alarm linkage threshold is set based on the absolute pressure value inside the negative pressure sealed chamber (1) during normal operation of the zinc-bromine flow battery.

8. A bromine leakage early warning system for a zinc-bromine flow battery according to claim 7, characterized in that, The preset alarm linkage threshold is the pressure difference between the inside of the negative pressure sealed chamber (1) and the atmospheric pressure of the external environment when they are equal.

9. A method for early warning of bromine leakage in a zinc-bromine flow battery, characterized in that, Using the bromine leakage early warning system for zinc-bromine flow batteries as described in any one of claims 1-9; The bromine leakage early warning method for zinc-bromine flow batteries includes: Real-time monitoring of the pressure difference between the inside of the negative pressure sealed chamber (1) and the external atmospheric pressure; Based on pressure difference data and according to preset pressure change criteria, it determines whether bromine leakage has occurred and generates a leakage warning signal or linkage control command; among which, the linkage control command is used to trigger the target battery to perform an emergency shutdown action.

10. A method for bromine leakage early warning in a zinc-bromine flow battery according to claim 9, characterized in that, The preset pressure change criteria include preset warning thresholds and preset alarm linkage thresholds; The preset warning threshold is set based on the rate of change of pressure difference inside the negative pressure sealed chamber (1) during normal operation of the zinc-bromine flow battery. The preset alarm linkage threshold is set based on the absolute pressure value inside the negative pressure sealed chamber (1) during normal operation of the zinc-bromine flow battery.

Images