Zinc-bromine flow battery fault identification method, system and equipment based on hydrogen leakage and medium

Abstract

The invention belongs to the technical field of flow battery energy storage, and discloses a zinc-bromine flow battery fault identification method, system and device based on hydrogen leakage and a medium, the identification method comprises the following steps: obtaining an actually measured pH value of an electrolyte in a negative electrode liquid storage tank of a zinc-bromine flow battery; based on a pH-SOC standard curve, according to the charge state value of the current charge and discharge state, obtaining a corresponding standard pH value; calculating the pH deviation between the actually measured pH value and a standard pH value; if the pH deviation is within a set threshold range, the zinc-bromine flow battery system has a hydrogen leakage fault, otherwise, the zinc-bromine flow battery system is normal. By comparing the actually measured pH value with the deviation of the standard curve in real time, the abnormal hydrogen evolution reaction can be quickly identified, the early warning and active protection of the hydrogen evolution side reaction of the zinc-bromine flow battery are realized, and the method is suitable for battery health management of a large-scale energy storage system.

Description

Technical Field

[0001] The present invention belongs to the technical field of liquid flow battery energy storage, and in particular relates to a method, system, equipment and medium for identifying zinc-bromine liquid flow battery faults based on hydrogen leakage. Background Art

[0002] Zinc-bromine flow batteries experience significant voltage polarization during charge and discharge, leading to high overvoltage during charging and a tendency to trigger the hydrogen evolution side reaction. The triggering condition for the hydrogen evolution side reaction is that the negative electrode potential during charging is lower than -0.414 V vs. Standard Hydrogen Electrode (SHE) (pH = 7), causing the following reaction to occur:

[0003] 2H2O+2e - →H2↑+2OH -

[0004] Each mol of H2 generated causes the pH of the electrolyte to increase by 1.0-1.5 units.

[0005] There are two main redox reaction pairs involved in zinc-bromine flow batteries: the redox reaction of bromine on the positive electrode (Br2 / Br - ) kinetics were slow (electrode potential was 1.087 V vs. SHE), while the negative electrode zinc deposition reaction (Zn 2+ / Zn) at a faster rate (electrode potential of -0.763V vs. SHE). This electrochemical polarization difference results in a larger overpotential during charging (above 200mV), causing the negative electrode potential to deviate significantly from the equilibrium state at the end of charging, resulting in hydrogen evolution side reaction. In addition, commercial zinc-bromine flow batteries generally use carbon-plastic bipolar plates with a conductivity of only 10-20S / cm, which is much lower than the graphite felt of all-vanadium flow batteries (above 100S / cm). Ohmic polarization further exacerbates energy loss. When the charging potential exceeds the critical value, a hydrogen evolution reaction occurs on the negative electrode side: 2H2O+2e - →H2↑+2OH - The triggering potential of this reaction is related to the pH of the electrolyte, and the weakly acidic environment of the zinc-bromine battery electrolyte further reduces the hydrogen evolution overpotential threshold, making it easy for polarization accumulation to break through the reaction threshold.

[0006] The side reaction of hydrogen evolution can cause multiple damages to battery performance and life. (1) OH generated by the reaction - Will break the hydrolysis balance of ZnBr2 ( K a =1.2×10 -9 ), resulting in a significant increase in the pH of the electrolyte. In addition, the alkaline environment promotes the deposition of Zn(OH)2 colloids and reduces the Zn 2+Effective concentration and cause imbalance in the chemical valence of the electrolyte. (2) High pH environment (pH>5.5) will accelerate the growth of zinc dendrites. Uneven zinc deposition can easily pierce the diaphragm, resulting in a significant increase in the risk of short circuits in the battery. (3) Hydrogen bubbles generated during hydrogen evolution will adhere to the electrode surface, forming an "air film" that hinders ion transmission, resulting in a decrease in charge transfer efficiency and capacity degradation.

[0007] The current battery management system (BMS) of zinc-bromine flow batteries has not yet established an effective detection mechanism for hydrogen evolution failures and mainly relies on status assessment methods with high hysteresis.

[0008] Currently, the state of charge (SOC) is estimated by the ampere-hour integration method (accuracy ±10%), and the battery health status is evaluated based on the capacity retention rate (which requires statistics after more than 100 cycles). However, these methods cannot locate specific faults such as hydrogen evolution in real time, and it is difficult to distinguish the specific causes of capacity decay (such as hydrogen evolution, loss of active substances, diaphragm aging, etc.).

[0009] In addition, sensor-based detection solutions have significant defects: hydrogen sensors cost as much as 2,000 yuan per set, and the fuel cell structure needs to be modified, resulting in poor engineering compatibility; therefore, existing technologies lack a highly reliable early warning method for hydrogen evolution failures, and there is an urgent need to achieve accurate identification and active control of failures through innovative detection mechanisms. Summary of the Invention

[0010] To address the problem that zinc-bromine flow batteries are prone to electrolyte pH imbalance caused by hydrogen evolution side reactions during charge and discharge, which is difficult to accurately monitor, the present invention aims to provide a zinc-bromine flow battery fault identification method, system, equipment, and medium based on hydrogen leakage, which can achieve early warning of hydrogen evolution reactions, fault level differentiation, and active protection, thereby improving battery cycle life and energy storage system safety.

[0011] In order to achieve the above object, the technical solution adopted by the present invention is:

[0012] A method for identifying zinc-bromine flow battery faults based on hydrogen leakage comprises the following steps:

[0013] Obtain the measured pH value of the electrolyte in the negative electrode storage tank of the zinc-bromine flow battery;

[0014] Based on the pH-SOC standard curve, the corresponding standard pH value is obtained according to the state of charge value of the current charge and discharge state;

[0015] Calculating the pH deviation between the measured pH value and the standard pH value;

[0016] If the pH deviation is within the set threshold range, a hydrogen leakage fault occurs in the zinc-bromine flow battery system; otherwise, the zinc-bromine flow battery system is normal.

[0017] A further improvement of the present invention is that the pH-SOC standard curve is established by the following method:

[0018] The zinc-bromine flow battery was charged and discharged, and the pH value of the electrolyte corresponding to different states of charge was recorded;

[0019] The pH values ​​of the electrolyte corresponding to the different states of charge are fitted to generate a pH-SOC standard curve.

[0020] A further improvement of the present invention is that the zinc-bromine flow battery is subjected to charge and discharge cycles at a rated current density of 20% to 50%.

[0021] A further improvement of the present invention is that the pH values ​​of the electrolyte corresponding to the different charge states are fitted using a cubic spline interpolation method.

[0022] A further improvement of the present invention is that when a hydrogen leakage fault occurs in the zinc-bromine liquid flow battery system, if the pH deviation ΔpH satisfies 0.5≤ΔpH<1.0, it is a first-level fault and an alarm is issued; if 1.0≤ΔpH<1.5, it is a second-level fault; if ΔpH≥1.5, it is a third-level fault. In the case of a second-level fault or a third-level fault, the battery is power controlled.

[0023] A further improvement of the present invention is that, in case of a first-level fault, the charging program is started with a delay of 5 to 10 minutes and a remote alarm is issued. In case of a second-level fault, the charging power is reduced to 50% to 70% of the rated value after 2 to 5 minutes. In case of a third-level fault, the charging circuit is cut off after 1 to 2 minutes and an alarm signal is issued.

[0024] A further improvement of the present invention is that the measured pH value of the electrolyte in the negative electrode storage tank of the zinc-bromine flow battery is obtained by a pH sensor.

[0025] A zinc-bromine flow battery fault identification system based on hydrogen leakage, comprising a measured pH value acquisition module, a standard pH value acquisition module, a data processing module and a hydrogen leakage fault determination module;

[0026] A measured pH value acquisition module is used to obtain the measured pH value of the electrolyte in the negative electrode storage tank of the zinc-bromine flow battery;

[0027] A standard pH value acquisition module is used to obtain the corresponding standard pH value according to the state of charge value of the current charge and discharge state based on the pH-SOC standard curve;

[0028] A data processing module is used to calculate the pH deviation between the measured pH value and the standard pH value;

[0029] The hydrogen leakage fault judgment module is used to determine if a hydrogen leakage fault occurs in the zinc-bromine liquid flow battery system if the pH deviation is within a set threshold range; otherwise, the zinc-bromine liquid flow battery system is normal.

[0030] An electronic device comprises a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for identifying zinc-bromine flow battery faults based on hydrogen leakage is implemented.

[0031] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method for identifying zinc-bromine flow battery faults based on hydrogen leakage is implemented.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] In the present invention, by comparing the deviation of the measured pH value with the standard curve in real time, abnormal hydrogen evolution reactions can be quickly identified, achieving early warning and active protection of hydrogen evolution side reactions in zinc-bromine flow batteries. This method is suitable for battery health management of large-scale energy storage systems and overcomes the defects of high hysteresis and insufficient accuracy of existing zinc-bromine flow battery fault detection technologies.

[0034] Furthermore, the present invention uses a bromine-resistant pH sensor to collect the pH value of the electrolyte in the negative electrode storage tank. This is low-cost and requires no modification to the fuel cell stack structure, addressing the shortcomings of existing detection solutions and providing a new, low-cost, highly compatible approach for hydrogen evolution fault detection. By comparing the measured pH value with the standard pH value and calculating the deviation to identify hydrogen leakage faults, this provides an indirect but accurate early warning of the hydrogen evolution side reaction, addressing the shortcomings of existing hysteresis-based state assessment methods and overcoming the high cost and poor engineering compatibility of existing hydrogen sensors.

[0035] Furthermore, a pH-SOC standard curve was established at 20%-50% of the rated current density, which can accurately reflect the dynamic relationship between pH value and state of charge (SOC) during normal charging and discharging.

[0036] Furthermore, the present invention proposes a three-level fault control strategy. This strategy uses a sliding window algorithm to suppress noise interference and classifies fault levels according to ΔpH thresholds (Level 1 fault: 0.5 ≤ ΔpH < 1.0; Level 2 fault: 1.0 ≤ ΔpH < 1.5; Level 3 fault: ΔpH ≥ 1.5). The strategy then dynamically adjusts charging power or disconnects the circuit accordingly. For example, a Level 1 fault triggers charging delay and remote alarm, a Level 2 fault reduces power to 50%-70%, and a Level 3 fault directly disconnects the charging circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0038] Figure 1 This is a control logic diagram of a zinc-bromine flow battery fault identification method based on hydrogen leakage according to the present invention;

[0039] Figure 2 The continuous pH-SOC curve is generated by using the cubic spline interpolation method in Example 1;

[0040] Figure 3 This is a battery performance diagram of Example 1;

[0041] Figure 4 This is a battery performance diagram of Comparative Example 1;

[0042] Figure 5 Schematic diagram of the zinc-bromine flow battery fault identification system based on hydrogen leakage of the present invention. DETAILED DESCRIPTION

[0043] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0044] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0045] Explanation of terms in this invention:

[0046] Controller Area Network bus: Controller Area Network, CAN;

[0047] Battery Management System: Battery Management System, BMS.

[0048] Battery state of charge: State of Charge, SOC.

[0049] The charge overpotential of zinc-bromine flow batteries is caused by the following factors:

[0050] The kinetics of the bromine redox reaction at the positive electrode is slow, while the zinc deposition reaction rate at the negative electrode is fast;

[0051] The conductivity of carbon plastic bipolar plates is lower than 10-20S / cm, resulting in significant ohmic polarization.

[0052] See also Figure 1 In order to solve the problem of charging overpotential of zinc-bromine liquid flow batteries, the present invention provides a zinc-bromine liquid flow battery fault identification method based on hydrogen leakage, comprising the following steps:

[0053] Step 1: pH sensor deployment;

[0054] Use a commercially available pH sensor with an accuracy of ±0.01 pH and a response time of <10 seconds. The pH sensor is a bromine-resistant solid-state electrode (e.g., Honeywell's Durafet II pH electrode) consisting of a housing and an electrode body positioned within it. The pH sensor should be vertically embedded in the center of the bottom of the zinc-bromine flow battery's negative electrode reservoir, 5 to 20 mm from the tank bottom to prevent sediment from depositing and affecting detection accuracy. Ensure that the pH sensor axis is parallel to the flow direction to ensure adequate electrolyte flow across the electrode surface. Automatic calibration is preferably performed monthly, switching between pH 4.00 (25°C) and pH 7.00 (25°C) standard buffer solutions and the electrolyte circuit using a three-way valve. Calibration should occur every 30 minutes.

[0055] Step 2: Establish a standard curve

[0056] Battery assembly: Select an effective area of ​​100 to 200 cm 2A zinc-bromine flow cell was assembled using carbon-plastic bipolar plates as electrodes and a commercial polyethylene porous membrane as a separator. The electrolyte composition includes ZnBr2, KCl, and a complexing agent (optionally tetrabutylammonium bromide, hexadecyltrimethylammonium bromide, or 1-methyl-1-ethylpyrrolidone bromide). The ZnBr2 concentration in the electrolyte is 1.5-2.5 mol / L, the KCl concentration is 2.5-3.5 mol / L, and the complexing agent concentration is 0.3-0.6 mol / L. The positive and negative electrolyte volumes are both 250-350 mL, and the circulation flow rate is 400-600 mL / min. The pH sensor is vertically embedded in the center of the bottom of the negative electrode reservoir, 10 mm from the bottom of the tank.

[0057] Data testing: The zinc-bromine flow battery was charged and discharged using a battery testing system, with the charge and discharge current density set at 4-10 mA / cm 2 (20% to 50% rated current density), charging time is 4 hours, and discharge cut-off voltage is 0.5 V. During the 5th to 10th cycle, the pH value is measured at different states of charge (10% to 20% steps) during three consecutive charging processes, namely SOC = 0%, SOC = 20%, SOC = 40%, SOC = 60%, SOC = 80%, and SOC = 100%. The average pH value at each SOC point is calculated, and a continuous pH-SOC standard curve is generated using the cubic spline interpolation method. The curve is stored in the Flash memory of the STM32 microcontroller (STMicroelectronics Microcontroller) as a standard curve database.

[0058] In the present invention, charging is performed at 20% to 50% of the rated current density, which can avoid hydrogen evolution caused by overpotential and ensure that the measured pH value only reflects the Zn content in the normal charging process. 2+ Hydrolysis equilibrium ( ).

[0059] Step 3: Real-time fault detection and control

[0060] The pH sensor collects the pH value of the electrolyte in the negative electrode storage tank of the zinc-bromine flow battery at a frequency of 1 to 5 times per minute. Each collection lasts for 5 seconds. Ten sample values ​​are averaged to filter out noise to obtain the measured pH value. The standard pH value under the corresponding SOC is obtained through the pH-SOC standard curve. Based on the measured pH value and the standard pH value, the sliding window algorithm is used to calculate the pH deviation. The calculation formula is:

[0061]

[0062] Where ΔpH avg is the average value of pH deviation, i is the ergodic variable (1≤i≤3), n is the number of samples, n=10, pH 实测,i is the pH value collected for the i-th time, pH标准,i The standard pH value corresponding to the SOC at the time of the i-th acquisition is used to suppress accidental interference through the sliding window algorithm. When the average pH deviation of two consecutive windows is ΔpH avg When the value is greater than or equal to the threshold, a response is triggered and a control action is performed. The three-level control actions are shown in Table 2.

[0063] Table 2 Three-level control actions

[0064]

[0065]

[0066] See also Figure 5 The zinc-bromine flow battery fault identification system based on hydrogen leakage includes a measured pH value acquisition module, a standard pH value acquisition module, a data processing module, a hydrogen leakage fault determination module, and further includes an alarm module and a power regulation module;

[0067] A measured pH value acquisition module is used to obtain the measured pH value of the electrolyte in the negative electrode storage tank of the zinc-bromine flow battery;

[0068] A standard pH value acquisition module is used to obtain the corresponding standard pH value according to the state of charge value of the current charge and discharge state based on the pH-SOC standard curve;

[0069] A data processing module is used to calculate the pH deviation between the measured pH value and the reference pH value. The data processing module has a processing delay of less than 10ms. The communication interface interacts with the BMS main controller in real time via an RS485 bus or a CAN bus. Alternatively, the data processing module can be integrated into the battery management system.

[0070] The hydrogen leakage fault judgment module is used to determine if a hydrogen leakage fault occurs in the zinc-bromine liquid flow battery system if the pH deviation is within a set threshold range. Specifically, if the pH deviation ΔpH satisfies 0.5≤ΔpH<1.0, it is a level one fault; if 1.0≤ΔpH<1.5, it is a level two fault; if ΔpH≥1.5, it is a level three fault; otherwise, the zinc-bromine liquid flow battery system is normal.

[0071] The alarm module is used to issue an audible and visual alarm when a level 1 fault occurs. The alarm module is connected to the BMS or can be integrated into the BMS.

[0072] The power regulation module is used to control battery power in the event of a secondary or tertiary fault. It supports 0-100% rated power regulation with a resolution of 0.1% and a response time of less than 500ms. It is connected to the battery management system or can be integrated into the battery management system.

[0073] Furthermore, the present invention realizes early warning and active protection of hydrogen evolution side reaction in zinc-bromine flow batteries through the collaboration of low-cost pH sensors and battery management systems, which is suitable for battery health management of large-scale energy storage systems.

[0074] Example 1

[0075] This embodiment 1 provides a method for identifying zinc-bromine flow battery faults based on hydrogen leakage, comprising the following steps:

[0076] Step 1: Battery system assembly

[0077] The stack structure adopts an effective area of ​​150cm 2 A single cell was assembled using a carbon-plastic composite bipolar plate (conductivity 15 S / cm) and a commercial polyethylene porous membrane (50 μm thick) as the separator. The positive and negative electrode reservoirs each had a capacity of 300 mL, and the circulation pump flow rate was set at 500 mL / min.

[0078] The electrolyte formula is 1.8 mol / L ZnBr2+3.0 mol / L KCl+0.4 mol / L tetrabutylammonium bromide (complexing agent), the initial pH is 3.2, and the electrolyte temperature is controlled at 25±2°C.

[0079] The pH sensor uses a commercially available platinum black-modified carbon nanotube electrode. The sensor is vertically embedded in the center of the bottom of the negative electrode reservoir, 10 mm from the bottom. It is automatically calibrated monthly using a three-way valve (pH 4.00 and 7.00 buffer solutions, with a 30-minute calibration cycle).

[0080] Step 2: Establishment of pH-SOC standard curve

[0081] Use 50% rated current (10mA / cm 2 , 1.5A) to charge the zinc-bromine flow battery to avoid the hydrogen evolution side reaction. When the cycle charge and discharge reached the 8th cycle, the pH values ​​at different SOC points during the three charging processes were collected. The data are shown in Table 3:

[0082] Table 3 Different SOC corresponding pH

[0083]

[0084]

[0085] The pH-SOC standard curve is generated by cubic spline interpolation and stored in the STM32 microcontroller. The pH-SOC standard curve is as follows: Figure 2 shown.

[0086] Step 3: High current density charging, real-time fault detection and control

[0087] At a current density exceeding the rated value of 40 mA / cm2 Charging at 6A, real-time negative electrode pH is collected at a sampling frequency of 3 times / minute, with an average of 10 samples taken each time. When charging to SOC = 85%, the measured pH is 4.3 (the pH-SOC standard curve corresponds to pH = 3.75), and ΔpH is calculated as |4.3 - 3.75| = 0.55, triggering a Level 1 fault: an alarm signal is sent to the BMS via RS485.

[0088] If not handled in time, when SOC = 90%, the pH rises to 4.9 (standard pH = 3.87), ΔpH = 1.37, triggering a secondary fault: the power regulation module reduces the charging power to 20% of the rated value (0.6A).

[0089] Step 4: Battery cycle test

[0090] The battery after the above test is subjected to a charge and discharge cycle test with a charge and discharge current density of 20mA / cm 2 , cycle test 30 times, record the discharge capacity of the flow battery in each cycle, and calculate the capacity retention rate of each cycle. The calculation formula is:

[0091]

[0092] Battery performance Figure 3 As shown in the figure, the capacity retention rate can reach 90.1% after 30 cycles.

[0093] Comparative Example 1

[0094] This comparative example 1 provides a zinc-bromine flow battery fault identification method based on hydrogen leakage, comprising the following steps:

[0095] Step 1: Battery system assembly

[0096] The stack structure adopts an effective area of ​​150cm 2 A single cell was assembled using a carbon-plastic composite bipolar plate (conductivity 15 S / cm) and a commercial polyethylene porous membrane (50 μm thick) as the separator. The positive and negative electrode reservoirs each had a capacity of 300 mL, and the circulation pump flow rate was set at 500 mL / min.

[0097] The electrolyte formula is 1.8 mol / L ZnBr2+3.0 mol / L KCl+0.4 mol / L tetrabutylammonium bromide (complexing agent), the initial pH is 3.2, and the electrolyte temperature is controlled at 25±2°C.

[0098] Step 2: High current density charging test

[0099] At a current density exceeding the rated value of 40 mA / cm 2 (6A) Charge to 100% SOC.

[0100] Step 3: Battery cycle test

[0101] The battery after the above test is subjected to a charge and discharge cycle test with a charge and discharge current density of 20mA / cm 2 , cycle test 30 times, record the discharge capacity of the flow battery in each cycle, calculate the capacity retention rate of each cycle, and the battery performance is as follows Figure 4 As shown in Figure 2, the capacity retention rate after 30 cycles is only 26.0%.

[0102] It can be seen from Example 1 and Comparative Example 1 that the method of the present invention is effective in suppressing electrolyte imbalance and extending battery life.

[0103] This embodiment achieves early warning and precise control of hydrogen evolution failures through dynamic pH-SOC mapping and a three-level control strategy. The accuracy of the battery fault identification method can be further optimized by adjusting the current density, complexing agent type, or sensor calibration cycle according to actual needs.

[0104] All relevant contents of each step involved in the embodiment of the zinc-bromine liquid flow battery fault identification method based on hydrogen leakage can be referred to the functional description of the functional modules corresponding to the zinc-bromine liquid flow battery fault identification system based on hydrogen leakage in the embodiment of the present invention, and will not be repeated here.

[0105] In one embodiment of the present invention, an electronic device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for identifying zinc-bromine flow battery faults based on hydrogen leakage is implemented.

[0106] In one embodiment of the present invention, a computer-readable storage medium is provided, specifically a computer-readable storage medium (Memory). The computer-readable storage medium is a memory device in a computer device for storing programs and data. It is understandable that the computer-readable storage medium here can include both built-in storage media in the computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space that stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space. These instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the zinc-bromine liquid flow battery fault identification method based on hydrogen leakage in the above embodiment.

[0107] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0108] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0109] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0110] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0111] 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 it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A method for identifying faults in zinc-bromine flow batteries based on hydrogen leakage, characterized in that: The following steps are involved: Obtain the measured pH value of the electrolyte in the negative electrode storage tank of the zinc-bromine flow battery; Based on the pH-SOC standard curve, the corresponding standard pH value is obtained according to the state of charge value of the current charge and discharge state; Calculating the pH deviation between the measured pH value and the standard pH value; If the pH deviation is within the set threshold range, a hydrogen leakage fault occurs in the zinc-bromine flow battery system; otherwise, the zinc-bromine flow battery system is normal.

2. The method for identifying zinc-bromine flow battery faults based on hydrogen leakage according to claim 1, characterized in that: The pH-SOC standard curve was established by the following method: The zinc-bromine flow battery was charged and discharged, and the pH value of the electrolyte corresponding to different states of charge was recorded; The pH values ​​of the electrolyte corresponding to the different states of charge are fitted to generate a pH-SOC standard curve.

3. The zinc-bromine flow battery fault identification method based on hydrogen leakage according to claim 2, characterized in that: The zinc-bromine flow battery was charged and discharged at a current density of 20% to 50% of the rated current density.

4. The zinc-bromine flow battery fault identification method based on hydrogen leakage according to claim 2, characterized in that: The pH values ​​of the electrolyte corresponding to the different charge states are fitted using the cubic spline interpolation method.

5. The zinc-bromine flow battery fault identification method based on hydrogen leakage according to claim 1, characterized in that: When a hydrogen leakage fault occurs in the zinc-bromine flow battery system, if the pH deviation ΔpH satisfies 0.5≤ΔpH<1.0, it is a level 1 fault and an alarm is issued. If 1.0≤ΔpH<1.5, it is a level 2 fault. If ΔpH≥1.5, it is a level 3 fault. In the case of a level 2 or level 3 fault, the battery power is controlled.

6. The method for identifying zinc-bromine flow battery faults based on hydrogen leakage according to claim 5, characterized in that: In case of a level 1 fault, the charging program will be started after a delay of 5 to 10 minutes and a remote alarm will be issued. In case of a level 2 fault, the charging power will be reduced to 50%-70% of the rated value after 2 to 5 minutes. In case of a level 3 fault, the charging circuit will be cut off after 1 to 2 minutes and an alarm signal will be issued.

7. The method for identifying zinc-bromine flow battery faults based on hydrogen leakage according to claim 5, characterized in that: The measured pH value of the electrolyte in the negative electrode storage tank of the zinc-bromine flow battery is obtained by a pH sensor.

8. A zinc-bromine flow battery fault identification system based on hydrogen leakage, characterized in that: It includes a measured pH value acquisition module, a standard pH value acquisition module, a data processing module and a hydrogen leakage fault judgment module; A measured pH value acquisition module is used to obtain the measured pH value of the electrolyte in the negative electrode storage tank of the zinc-bromine flow battery; A standard pH value acquisition module is used to obtain the corresponding standard pH value according to the state of charge value of the current charge and discharge state based on the pH-SOC standard curve; A data processing module is used to calculate the pH deviation between the measured pH value and the standard pH value; The hydrogen leakage fault judgment module is used to determine if a hydrogen leakage fault occurs in the zinc-bromine liquid flow battery system if the pH deviation is within a set threshold range; otherwise, the zinc-bromine liquid flow battery system is normal.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the zinc-bromine flow battery fault identification method based on hydrogen leakage as described in any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method for identifying zinc-bromine flow battery faults based on hydrogen leakage according to any one of claims 1 to 7 is implemented.

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