A real-time monitoring method and system for hydrogen evolution reaction in a flow battery

Abstract

The present invention relates to a real-time monitoring method and system for hydrogen evolution reaction of a liquid flow battery, the method comprising: obtaining real-time data in a battery management system; using simultaneous equations to calculate the concentration of hydrogen ions in a positive electrode electrolyte in a liquid flow battery; calculating the equilibrium potential of the negative electrode according to the equilibrium potential of the positive electrode according to the concentration of hydrogen ions in the positive electrode electrolyte; calculating the equilibrium potential of the negative electrode hydrogen evolution reaction according to the equilibrium potential of the negative electrode hydrogen evolution reaction; calculating the concentration of hydrogen ions in the negative electrode electrolyte according to the equilibrium potential of the negative electrode hydrogen evolution reaction; calculating the amount of hydrogen ion substance used for hydrogen evolution according to the concentration of hydrogen ions in the negative electrode electrolyte and the simultaneous equations; calculating the amount of hydrogen gas precipitated according to the amount of hydrogen ion substance used for hydrogen evolution. The present invention establishes an electrochemical calculation formula through BMS real-time data, does not need a gas concentration sensor to monitor the gas phase concentration, thereby reducing costs and improving system real-time performance, and the monitoring results are not affected by operating condition fluctuations, thereby improving data reliability.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid flow batteries, and in particular to a real-time monitoring method and system for hydrogen evolution reaction in liquid flow batteries. Background Art

[0002] In liquid flow batteries, the positive and negative electrodes of all-vanadium liquid flow batteries both use acid solutions containing vanadium ions of different valence states as electrolytes. During the charging process of all-vanadium liquid flow batteries, side reactions will inevitably occur. The capacity loss caused by some side reactions (such as vanadium ion cross-membrane crossing, water volume transfer, etc.) can be restored by simple mixing of liquids; but other side reactions of gas evolution cause Faraday imbalance, which cannot be simply compensated by mixing of liquids. These side reactions will cause the attenuation of coulombic efficiency, voltage efficiency, energy efficiency, and system efficiency, and shorten the life of the liquid flow battery. Therefore, it is particularly necessary to monitor these gas evolution side reactions. Hydrogen, oxygen, and carbon dioxide are the main side reaction gases. Since the equilibrium potential of the hydrogen evolution reaction (0.0Vvs.SHE) is greater than the reduction potential of the negative electrode vanadium ions (-0.255Vvs.SHE), the hydrogen evolution reaction is the most important one.

[0003] At present, hydrogen concentration detection instruments are usually used for preliminary testing. However, these hydrogen concentration detection results are themselves related to the operating conditions of the battery stack (such as operating current density, etc.), and it is necessary to install hydrogen concentration detection instruments and other devices on the battery system, which leads to increased R&D, production and maintenance costs.

[0004] Therefore, it is necessary to provide a new real-time monitoring method for hydrogen evolution reaction in liquid flow batteries. Summary of the invention

[0005] Based on the above problems existing in the prior art, the purpose of the embodiments of the present invention is to provide a real-time monitoring method and system for the hydrogen evolution reaction of a liquid flow battery, by establishing an electrochemical calculation formula through the real-time data of the BMS, without the need for a gas concentration sensor to monitor the gas phase concentration, thereby reducing costs and improving the real-time performance of the system. The monitoring results are not affected by fluctuations in operating conditions, thereby improving data reliability.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a real-time monitoring method for hydrogen evolution reaction in a liquid flow battery, comprising:

[0007] Obtain real-time data within the battery management system;

[0008] The simultaneous equations are used to calculate the hydrogen ion concentration in the positive electrolyte of the flow battery;

[0009] According to the concentration of hydrogen ions in the positive electrode electrolyte, the negative electrode equilibrium mixed potential is calculated in combination with the positive electrode equilibrium potential;

[0010] Calculate the equilibrium potential of the negative electrode hydrogen evolution reaction based on the negative electrode equilibrium mixed potential;

[0011] Calculate the hydrogen ion concentration in the negative electrode electrolyte according to the equilibrium potential of the negative electrode hydrogen evolution reaction;

[0012] Calculate the amount of hydrogen ion substance used for hydrogen evolution based on the hydrogen ion concentration in the negative electrode electrolyte and the simultaneous equation;

[0013] The amount of the substance that releases hydrogen is calculated based on the amount of the substance that produces hydrogen ions.

[0014] Furthermore, the real-time data acquisition in the battery management system includes: acquiring the state of charge SOC, open circuit voltage OCV, sampling time, sampling times, acquiring the total amount of vanadium in the positive electrode electrolyte, monitoring the volume of the positive and negative electrode electrolytes respectively, and collecting and calculating the average temperature of the electrolyte in the positive electrode storage tank and the negative electrode storage tank of the liquid flow battery.

[0015] Further, the method of using simultaneous equations to calculate the concentration of hydrogen ions in the positive electrode electrolyte in the flow battery includes: calculating the positive electrode hydrogen ion concentration calculation formula, the amount conservation equation of the positive electrode hydrogen ion, the amount increment calculation formula of the positive electrode hydrogen ion substance caused by the electrochemical reaction and migration, and the positive electrode due to The calculation formula for the amount of hydrogen ion substance increased due to dissociation equilibrium, the positive electrode electrolyte The dissociation equilibrium equation and the positive electrolyte The dissociation rate calculation formula is combined to solve the hydrogen ion concentration in the positive electrode electrolyte.

[0016] Furthermore, the calculation formula for the positive electrode hydrogen ion concentration is:

[0017]

[0018] in, is the concentration of hydrogen ions in the cathode electrolyte at the time of the i-th sampling, in mol / L; is the amount of hydrogen ions in the positive electrode electrolyte at the time of the i-th sampling, in mol; is the volume of the cathode electrolyte at the i-th sampling, in L;

[0019] The substance conservation equation of the positive electrode hydrogen ion is:

[0020]

[0021] in, is the amount of hydrogen ions in the positive electrode electrolyte at the i-1th sampling, in mol; is the amount of hydrogen ions in the positive electrode electrolyte caused by the battery electrochemical reaction and migration during the i-th sampling period, in mol; The increase in the amount of substance of hydrogen ions in the positive electrolyte due to the dissociation equilibrium during the i-th sampling period, with the unit of mol;

[0022] The formula for calculating the increase in the amount of substance of hydrogen ions in the positive electrode due to electrochemical reaction and migration is:

[0023]

[0024] where, is the state of charge of the all-vanadium redox flow battery at the i-th sampling; is the state of charge of the all-vanadium redox flow battery at the (i - 1)-th sampling; is the total amount of vanadium in the positive electrolyte, with the unit of mol;

[0025] The positive electrode due to The formula for calculating the increase in the amount of substance of hydrogen ions caused by the dissociation equilibrium is:

[0026]

[0027] where, is the dissociation rate of in the positive electrolyte at the i-th sampling, with the unit of mol / (L*s); is the time interval of the i-th sampling period, with the unit of s;

[0028] The dissociation equilibrium equation of in the positive electrolyte is:

[0029]

[0030] where, is the amount of substance of in the positive electrolyte at the i-th sampling, with the unit of mol; is the amount of substance of in the positive electrolyte at the (i - 1)-th sampling, with the unit of mol.

[0031] The formula for calculating the dissociation rate of in the positive electrolyte is:

[0032]

[0033] where, is the rate parameter, taking 10 mol / (L*s); β is the degree of dissociation, taking 0.25; is the activity coefficient of hydrogen ions, taking 1; is the activity coefficient of, taking 1.

[0034] Further, the formula for calculating the negative electrode equilibrium mixed potential is:

[0035]

[0036] Wherein, is the negative electrode equilibrium mixed potential of the all-vanadium redox flow battery at the i-th sampling, with the unit of V; is the open-circuit voltage of the all-vanadium redox flow battery at the i-th sampling, with the unit of V; is the positive electrode equilibrium potential of the all-vanadium redox flow battery at the i-th sampling, with the unit of V;

[0037] The formula for calculating the positive electrode equilibrium potential of the all-vanadium redox flow battery is:

[0038]

[0039] Wherein, is the standard equilibrium potential of the positive electrode of the all-vanadium redox flow battery, which is 1.00 V; R is the gas constant, which is 8.314 J / (mol·K); is the temperature of the all-vanadium redox flow battery at the i-th sampling, with the unit of K; F is the Faraday constant, which is 96485 C / mol; is the concentration of hydrogen ions in the positive electrode electrolyte at the i-th sampling, with the unit of mol / L; is the activity coefficient of hydrogen ions, taken as 1; is the standard concentration, which is 1 mol / L; is the state of charge of the all-vanadium redox flow battery at the i-th sampling; is the activity coefficient of vanadium penta-ion in the positive electrode electrolyte, taken as 1; is the activity coefficient of vanadium tetra-ion in the positive electrode electrolyte, taken as 1.

[0040] Further, the formula for calculating the equilibrium potential of the negative electrode hydrogen evolution reaction is:

[0041]

[0042] Wherein, is the equilibrium potential of the negative electrode hydrogen evolution reaction at the i-th sampling, with the unit of V; is the exchange current density of the negative electrode vanadium ion reaction, taken as 1E-4 A / ; is the exchange current density of the negative electrode hydrogen evolution reaction, taken as 1E-6 A / ; is the equilibrium potential of the negative electrode vanadium ion reaction at the i-th sampling, with the unit of V; is the negative electrode equilibrium mixed potential of the all-vanadium redox flow battery at the i-th sampling, with the unit of V.

[0043] The calculation formula for the equilibrium potential of the negative electrode vanadium ion reaction is:

[0044]

[0045] in, is the standard equilibrium potential of the negative electrode vanadium ion reaction, which is -0.255V; is the activity coefficient of the divalent vanadium ion in the negative electrode electrolyte, which is taken as 1; is the activity coefficient of the trivalent vanadium ion in the negative electrode electrolyte, which is taken as 1; R is the gas constant, which is 8.314 J / (mol·K); is the temperature of the all-vanadium liquid flow battery at the i-th sampling, in K; F is the Faraday constant, which is 96485C / mol; is the power state of the all-vanadium liquid flow battery at the i-th sampling time.

[0046] Furthermore, the calculation formula for calculating the hydrogen ion concentration in the negative electrode electrolyte according to the equilibrium potential of the negative electrode hydrogen evolution reaction is:

[0047]

[0048] in, is the equilibrium potential of the hydrogen evolution reaction at the negative electrode during the i-th sampling, in V; R is the gas constant, which is 8.314 J / (mol·K); is the temperature of the all-vanadium liquid flow battery at the i-th sampling, in K; F is the Faraday constant, which is 96485C / mol; is the activity coefficient of hydrogen ions, which is taken as 1; is the standard concentration, 1 mol / L; is the concentration of hydrogen ions in the negative electrode electrolyte at the i-th sampling, in mol / L; is the standard equilibrium potential of the hydrogen evolution reaction, which is 0 V.

[0049] Further, the amount of hydrogen ion substance used for hydrogen evolution is calculated according to the hydrogen ion concentration in the negative electrode electrolyte and the parallel equations, including: the amount of hydrogen ion substance consumed by the negative electrode due to the hydrogen evolution side reaction, the amount of hydrogen ion substance in the negative electrode electrolyte, the amount of hydrogen ion substance increment calculation formula caused by the migration of the negative electrode due to the electrochemical reaction, and the amount of hydrogen ion substance consumed by the negative electrode due to the electrochemical reaction. The calculation formula for the amount of hydrogen ion substance increased due to dissociation equilibrium, the negative electrode electrolyte The dissociation equilibrium equation and the negative electrode electrolyte The dissociation rate calculation formula is combined to solve the amount of hydrogen ion substance used for hydrogen evolution;

[0050] The calculation formula for the amount of hydrogen ion substances consumed by the negative electrode due to the hydrogen evolution side reaction is:

[0051]

[0052] Among them, is the amount of substance of hydrogen ions consumed due to the occurrence of the hydrogen evolution side reaction during the \(i\)-th sampling period, with the unit of mol; is the amount of substance of hydrogen ions in the negative electrode electrolyte during the \((i - 1)\)-th sampling, with the unit of mol; is the increase in the amount of substance of hydrogen ions caused by migration due to the battery electrochemical reaction during the \(i\)-th sampling period, in mol; During the \(i\)-th sampling period, due to the dissociation equilibrium, the increase in the amount of substance of hydrogen ions, in mol; is the amount of substance of hydrogen ions in the negative electrode electrolyte during the \(i\)-th sampling, in mol;

[0053] The formula for calculating the amount of substance of hydrogen ions in the negative electrode electrolyte is:

[0054]

[0055] Among them, is the concentration of hydrogen ions in the negative electrode electrolyte during the \(i\)-th sampling, with the unit of mol / L; is the volume of the negative electrode electrolyte during the \(i\)-th sampling, with the unit of L;

[0056] The formula for calculating the increase in the amount of substance of hydrogen ions caused by migration due to the electrochemical reaction of the negative electrode is:

[0057]

[0058] Among them, is the state of charge of the all-vanadium redox flow battery during the \(i\)-th sampling; is the state of charge of the all-vanadium redox flow battery during the \((i - 1)\)-th sampling; is the total amount of vanadium in the positive electrode electrolyte, with the unit of mol;

[0059] For the negative electrode, due to the dissociation equilibrium, the formula for calculating the increase in the amount of substance of hydrogen ions is:

[0060]

[0061] Among them, is the dissociation rate of in the negative electrode electrolyte during the \(i\)-th sampling, with the unit of mol / (L·s); is the time interval of the \(i\)-th sampling period, with the unit of s;

[0062] For the negative electrode electrolyte, the dissociation equilibrium equation is:

[0063]

[0064] wherein, is the amount of substance of in the negative electrode electrolyte at the i-th sampling, with the unit of mol; is the amount of substance of in the negative electrode electrolyte at the (i - 1)-th sampling, with the unit of mol;

[0065] For the negative electrode electrolyte the dissociation rate calculation formula is:

[0066]

[0067] wherein, is the rate parameter, taking 10 mol / (L*s); β is the degree of dissociation, which can take 0.25; is the activity coefficient of hydrogen ions, taking 1; is the activity coefficient of, taking 1.

[0068] Furthermore, the calculation formula for the amount of substance of the evolved hydrogen is:

[0069]

[0070] wherein, is the total amount of substance of the evolved hydrogen from the initial moment to the i-th sampling, with the unit of mol; is the amount of substance of hydrogen ions consumed due to the hydrogen evolution side reaction during the i-th sampling period, with the unit of mol.

[0071] A real-time monitoring system for the hydrogen evolution reaction of a flow battery, which is applied to the above-mentioned real-time monitoring method for the hydrogen evolution reaction of a flow battery. The system includes:

[0072] A data acquisition module, which is used to acquire real-time data in the battery management system;

[0073] A positive electrode hydrogen ion concentration calculation module, which is used to calculate the hydrogen ion concentration in the positive electrode electrolyte of the flow battery by using a system of simultaneous equations;

[0074] A negative electrode equilibrium mixed potential calculation module, which is used to calculate the negative electrode equilibrium mixed potential according to the hydrogen ion concentration in the positive electrode electrolyte and in combination with the positive electrode equilibrium potential;

[0075] A negative electrode equilibrium potential calculation module, which is used to calculate the equilibrium potential of the hydrogen evolution reaction at the negative electrode according to the negative electrode equilibrium mixed potential;

[0076] The negative electrode hydrogen ion concentration calculation module is used to calculate the hydrogen ion concentration in the negative electrode electrolyte according to the equilibrium potential of the hydrogen evolution reaction at the negative electrode;

[0077] The hydrogen ion amount calculation module is used to calculate the amount of hydrogen ions for hydrogen evolution according to the hydrogen ion concentration in the negative electrode electrolyte and by solving simultaneous equations;

[0078] The hydrogen gas amount calculation module is used to calculate the amount of hydrogen gas evolved according to the amount of hydrogen ions for hydrogen evolution.

[0079] The beneficial effects of the present invention are as follows: A real-time monitoring method for the hydrogen evolution reaction of a flow battery according to the present invention includes: obtaining real-time data in the battery management system; calculating the hydrogen ion concentration in the positive electrode electrolyte of the flow battery by solving simultaneous equations; calculating the negative electrode equilibrium mixed potential according to the hydrogen ion concentration in the positive electrode electrolyte and in combination with the positive electrode equilibrium potential; calculating the equilibrium potential of the hydrogen evolution reaction at the negative electrode according to the negative electrode equilibrium mixed potential; calculating the hydrogen ion concentration in the negative electrode electrolyte according to the equilibrium potential of the hydrogen evolution reaction at the negative electrode; calculating the amount of hydrogen ions for hydrogen evolution according to the hydrogen ion concentration in the negative electrode electrolyte and by solving simultaneous equations; calculating the amount of hydrogen gas evolved according to the amount of hydrogen ions for hydrogen evolution. The real-time monitoring method for the hydrogen evolution reaction of the flow battery according to the present invention uses the real-time data of the battery management system BMS to establish an electrochemistry calculation formula, can dynamically monitor the hydrogen evolution side reaction of the flow battery without installing a hydrogen concentration sensor, saves the installation and maintenance costs of the hydrogen detection device and thus reduces costs; based on the BMS real-time data, can quickly reflect the change trend of the hydrogen evolution side reaction, improving the real-time performance of the system; separates the hydrogen evolution current and the main reaction current through the calculation model, directly quantifies the additional consumption ratio of electrons by the side reaction, i.e., the hydrogen evolution current ratio, and the result is not affected by the fluctuations of working conditions such as the working current density, improving the reliability of the system data; and only needs to adjust the ion expression to be extended to other flow batteries, with universality and strong compatibility. Description of the Drawings

[0080] The present invention will be further described below with reference to the drawings and embodiments.

[0081] In the figure:

[0082] Figure 1 is the flowchart of the real-time monitoring method for the hydrogen evolution reaction of the flow battery provided by the first embodiment of the present invention;

[0083] Figure 2 is the module schematic diagram of the real-time monitoring system for the hydrogen evolution reaction of the flow battery provided by the second embodiment of the present invention;

[0084] Figure 3 is the structural schematic diagram of the network-side server provided by the third embodiment of the present invention. Detailed Embodiments

[0085] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0086] First embodiment:

[0087] The first embodiment of the present invention provides a real-time monitoring method for hydrogen evolution reaction in a liquid flow battery, comprising: acquiring real-time data in a battery management system; calculating the concentration of hydrogen ions in a positive electrode electrolyte in the liquid flow battery by using simultaneous equations; calculating the equilibrium mixed potential of the negative electrode according to the concentration of hydrogen ions in the positive electrode electrolyte in combination with the equilibrium potential of the positive electrode; calculating the equilibrium potential of the negative electrode hydrogen evolution reaction according to the equilibrium mixed potential of the negative electrode; calculating the concentration of hydrogen ions in the negative electrode electrolyte according to the equilibrium potential of the negative electrode hydrogen evolution reaction; calculating the amount of hydrogen ions used for hydrogen evolution according to the concentration of hydrogen ions in the negative electrode electrolyte and the simultaneous equations; and calculating the amount of hydrogen gas released according to the amount of hydrogen ions used for hydrogen evolution. The method for real-time monitoring of hydrogen evolution reaction in a liquid flow battery of the present invention uses real-time data of a battery management system BMS to establish an electrochemical calculation formula, and can dynamically monitor the hydrogen evolution side reaction of the liquid flow battery without the need to add a hydrogen concentration sensor, thereby eliminating the installation and maintenance costs of a hydrogen detection device and thus reducing costs; based on the real-time data of the BMS, the changing trend of the hydrogen evolution side reaction can be quickly reflected, thereby improving the real-time performance of the system; the hydrogen evolution current and the main reaction current are separated by a calculation model, and the additional consumption ratio of electrons by the side reaction, i.e., the hydrogen evolution current ratio, is directly quantified, and the result is not affected by fluctuations in operating conditions such as working current density, thereby improving the reliability of system data; and the method can be extended to other liquid flow batteries by only adjusting the ion expression, thereby having universality and strong compatibility.

[0088] The following is a detailed description of the implementation details of the real-time monitoring method for hydrogen evolution reaction in a liquid flow battery of this embodiment. The following content is only provided for the convenience of understanding the implementation details and is not necessary for the implementation of this solution. The specific process of this embodiment is as follows: Figure 1 shown.

[0089] Step S1, obtaining real-time data in the battery management system.

[0090] Specifically, obtaining real-time data in the battery management system BMS includes: obtaining the state of charge SOC, open circuit voltage OCV, sampling time, sampling times, obtaining the total vanadium content in the positive electrode electrolyte, monitoring the volume of the positive and negative electrode electrolytes respectively, and collecting and calculating the average temperature of the electrolyte in the positive and negative electrode storage tanks of the liquid flow battery.

[0091] Furthermore, the volumes of the positive and negative electrolyte solutions in the flow battery can be obtained from the liquid level monitoring data in the positive and negative liquid storage tanks.

[0092] Furthermore, the average current of the flow battery can also be collected.

[0093] Step S2: Calculate the hydrogen ion concentration in the positive electrolyte solution of the flow battery by using a set of simultaneous equations.

[0094] Specifically, the calculation of the hydrogen ion concentration in the positive electrolyte solution of the flow battery by using a set of simultaneous equations includes: By combining the positive hydrogen ion concentration calculation formula, the positive hydrogen ion amount conservation equation, the positive hydrogen ion amount increment calculation formula caused by electrochemical reaction and migration in the positive electrode, and the positive hydrogen ion amount increment calculation formula caused by dissociation equilibrium, the dissociation equilibrium equation in the positive electrolyte solution, and the dissociation rate calculation formula in the positive electrolyte solution, and solving to obtain the hydrogen ion concentration in the positive electrolyte solution.

[0095] The positive hydrogen ion concentration calculation formula is:

[0096]

[0097] where, is the hydrogen ion concentration in the positive electrolyte solution at the i-th sampling, with the unit of mol / L; is the amount of hydrogen ions in the positive electrolyte solution at the i-th sampling, with the unit of mol; is the volume of the positive electrolyte solution at the i-th sampling, with the unit of L, , is the total number of samplings.

[0098] The positive hydrogen ion amount conservation equation is:

[0099]

[0100] where, is the amount of hydrogen ions in the positive electrolyte solution at the (i - 1)-th sampling, with the unit of mol; is the increment of the amount of hydrogen ions in the positive electrolyte solution due to the electrochemical reaction and migration in the battery during the i-th sampling period, with the unit of mol; is the increment of the amount of hydrogen ions in the positive electrolyte solution due to dissociation equilibrium during the i-th sampling period, with the unit of mol.

[0101] Further, the i-th sampling period is the time period between the (i - 1)-th sampling and the i-th sampling. The first sampling period refers to the time period between the initial moment and the first sampling moment. When i = 1, is the amount of substance of hydrogen ions in the positive electrolyte at the initial moment, which is obtained according to the initial concentration of sulfuric acid in the positive electrolyte and the dissociation equilibrium.

[0102] The calculation formula for the increase in the amount of substance of hydrogen ions in the positive electrode due to electrochemical reaction and migration is:

[0103]

[0104] where, is the state of charge of the all-vanadium redox flow battery at the i-th sampling; is the state of charge of the all-vanadium redox flow battery at the (i - 1)-th sampling; is the total amount of vanadium in the positive electrolyte, with the unit of mol.

[0105] Further, the total amount of vanadium in the positive electrolyte can be read from the battery management system BMS or directly replaced by the initial total amount of vanadium in the positive electrolyte.

[0106] The positive electrode due to The calculation formula for the increase in the amount of substance of hydrogen ions caused by dissociation equilibrium is:

[0107]

[0108] where, is the dissociation rate of in the positive electrolyte at the i-th sampling, with the unit of mol / (L*s); is the time interval of the i-th sampling period, with the unit of s.

[0109] In the positive electrolyte The dissociation equilibrium equation is:

[0110]

[0111] where, is the amount of substance of in the positive electrolyte at the i-th sampling, with the unit of mol; is the amount of substance of in the positive electrolyte at the (i - 1)-th sampling, with the unit of mol.

[0112] In the positive electrolyte The calculation formula for the dissociation rate is:

[0113]

[0114] Among them, is the rate parameter and can take 10 mol / (L*s); β is the degree of dissociation and can take 0.25; is the activity coefficient of hydrogen ions and can take 1; is the activity coefficient of and can take 1.

[0115] When i is 1, represents the amount of substance of ions in the positive electrolyte at the initial moment, and is obtained according to the initial concentration of sulfuric acid in the positive electrolyte and the dissociation equilibrium;

[0116] Step S3: Calculate the negative electrode equilibrium mixed potential according to the hydrogen ion concentration in the positive electrolyte and in combination with the positive electrode equilibrium potential.

[0117] Specifically, the calculation formula for the negative electrode equilibrium mixed potential is:

[0118]

[0119] Among them, is the negative electrode equilibrium mixed potential of the all-vanadium redox flow battery at the i-th sampling, with the unit of V; is the open-circuit voltage of the all-vanadium redox flow battery at the i-th sampling, with the unit of V; is the positive electrode equilibrium potential of the all-vanadium redox flow battery at the i-th sampling, with the unit of V.

[0120] Furthermore, the open-circuit voltage of the all-vanadium redox flow battery at the i-th sampling is obtained from the battery management system BMS.

[0121] The calculation formula for the positive electrode equilibrium potential of the all-vanadium redox flow battery is:

[0122]

[0123] Among them, is the standard equilibrium potential of the positive electrode of the all-vanadium redox flow battery and is 1.00 V; R is the gas constant and is 8.314 J / (mol·K); is the temperature of the all-vanadium redox flow battery at the i-th sampling, with the unit of K; F is the Faraday constant and is 96485 C / mol; is the activity coefficient of hydrogen ions and can take 1; is the standard concentration and is 1 mol / L; is the state of charge of the all-vanadium redox flow battery at the i-th sampling; is the activity coefficient of vanadium pentoxide ions in the positive electrolyte and can take 1; is the activity coefficient of tetravalent vanadium ions in the positive electrolyte and can be taken as 1.

[0124] Furthermore, the state of charge of the all-vanadium redox flow battery at the i-th sampling is obtained from the battery management system (BMS); the temperature of the all-vanadium redox flow battery at the i-th sampling , taking the average temperature of the electrolytes in the positive and negative storage tanks, is obtained from the battery management system (BMS).

[0125] Step S4: Calculate the equilibrium potential of the hydrogen evolution reaction at the negative electrode according to the negative electrode balance mixed potential.

[0126] Specifically, the calculation formula for the equilibrium potential of the hydrogen evolution reaction at the negative electrode is:

[0127]

[0128] where is the equilibrium potential of the hydrogen evolution reaction at the negative electrode at the i-th sampling, with the unit of V; is the exchange current density of the vanadium ion reaction at the negative electrode and can be taken as 1E-4 A / , or can also be obtained through experiments; is the exchange current density of the hydrogen evolution reaction at the negative electrode and can be taken as 1E-6 A / , or can also be obtained through experiments; is the equilibrium potential of the vanadium ion reaction at the negative electrode at the i-th sampling, with the unit of V.

[0129] The calculation formula for the equilibrium potential of the vanadium ion reaction at the negative electrode is:

[0130]

[0131] where is the standard equilibrium potential of the vanadium ion reaction at the negative electrode, which is -0.255 V; is the activity coefficient of divalent vanadium ions in the negative electrolyte and can be taken as 1; is the activity coefficient of trivalent vanadium ions in the negative electrolyte and can be taken as 1.

[0132] Step S5: Calculate the hydrogen ion concentration in the negative electrolyte according to the equilibrium potential of the hydrogen evolution reaction at the negative electrode.

[0133] Specifically, the calculation formula for calculating the hydrogen ion concentration in the negative electrolyte according to the equilibrium potential of the hydrogen evolution reaction at the negative electrode is:

[0134]

[0135] where is the concentration of hydrogen ions in the negative electrolyte at the i-th sampling, with the unit of mol / L; is the standard equilibrium potential of the hydrogen evolution reaction, which is 0 V.

[0136] Step S6, calculating the amount of the substance of hydrogen ions used for hydrogen evolution according to the hydrogen ion concentration in the negative electrode electrolyte and the simultaneous equations.

[0137] Specifically, the amount of hydrogen ion substance used for hydrogen evolution is calculated according to the hydrogen ion concentration in the negative electrode electrolyte and the parallel equations, including: the amount of hydrogen ion substance consumed by the negative electrode due to the hydrogen evolution side reaction, the amount of hydrogen ion substance in the negative electrode electrolyte, the amount of hydrogen ion substance increment calculation formula caused by the migration of the negative electrode due to the electrochemical reaction, and the amount of hydrogen ion substance consumed by the negative electrode due to the electrochemical reaction. The calculation formula for the amount of hydrogen ion substance increased due to dissociation equilibrium, the negative electrode electrolyte The dissociation equilibrium equation and the negative electrode electrolyte The dissociation rate calculation formula is combined to solve the amount of hydrogen ion substance used for hydrogen evolution.

[0138] The calculation formula for the amount of hydrogen ion substances consumed by the negative electrode due to the hydrogen evolution side reaction is:

[0139]

[0140] in, is the amount of hydrogen ions consumed by the hydrogen evolution side reaction during the i-th sampling period, in mol; is the amount of hydrogen ions in the negative electrode electrolyte at the i-1th sampling, in mol; is the amount of hydrogen ion substance increase caused by the migration of the battery electrochemical reaction during the i-th sampling period, mol; is the number of samples in the ith sampling period due to The amount of hydrogen ion substance increased due to dissociation equilibrium, mol; is the amount of hydrogen ions in the negative electrode electrolyte at the i-th sampling, mol.

[0141] Furthermore, when i is 1, is the amount of hydrogen ions in the negative electrode electrolyte at the initial moment, according to the initial concentration of sulfuric acid in the negative electrode electrolyte and The dissociation equilibrium is obtained.

[0142] The calculation formula for the amount of hydrogen ion substance in the negative electrode electrolyte is:

[0143]

[0144] in, is the concentration of hydrogen ions in the negative electrode electrolyte at the i-th sampling, in mol / L; is the volume of the negative electrolyte during the i-th sampling, with the unit of L.

[0145] The calculation formula for the increment of the amount of substance of hydrogen ions caused by the migration of the negative electrode due to the electrochemical reaction is:

[0146]

[0147] where, is the state of charge of the all-vanadium redox flow battery during the i-th sampling; is the state of charge of the all-vanadium redox flow battery during the (i - 1)-th sampling; is the total amount of vanadium in the positive electrolyte, with the unit of mol.

[0148] Furthermore, the total amount of vanadium in the positive electrolyte is read from the battery management system BMS, or can be directly replaced by the initial total amount of vanadium in the positive electrolyte.

[0149] The negative electrode due to The calculation formula for the increment of the amount of substance of hydrogen ions caused by the dissociation equilibrium is:

[0150]

[0151] where, is the dissociation rate of in the negative electrolyte during the i-th sampling, with the unit of mol / (L*s); is the time interval of the i-th sampling period, with the unit of s.

[0152] In the negative electrolyte The dissociation equilibrium equation is:

[0153]

[0154] where, is the amount of substance of in the negative electrolyte during the i-th sampling, with the unit of mol; is the amount of substance of in the negative electrolyte during the (i - 1)-th sampling, with the unit of mol.

[0155] Furthermore, when i is 1, is the amount of substance of in the negative electrolyte at the initial moment, which is obtained according to the initial concentration of sulfuric acid in the negative electrolyte and the dissociation equilibrium.

[0156] In the negative electrolyte The calculation formula for the dissociation rate is:

[0157]

[0158] Among them, is the rate parameter and can take 10 mol / (L*s); β is the degree of dissociation and can take 0.25; is the activity coefficient of hydrogen ions and can take 1; is the activity coefficient of

[0159] Step S7: Calculate the amount of hydrogen gas precipitated according to the amount of substance of hydrogen ions used for hydrogen evolution.

[0160] Specifically, the calculation formula for the amount of substance of the precipitated hydrogen gas is:

[0161]

[0162] Among them, is the total amount of substance of the precipitated hydrogen gas from the initial moment to the i-th sampling, with the unit of mol.

[0163] Step S8: Calculate the hydrogen evolution rate and the proportion of hydrogen evolution current according to the amount of substance of hydrogen ions used for hydrogen evolution.

[0164] Specifically, the calculation formula for the hydrogen evolution rate is:

[0165]

[0166] Among them, is the hydrogen evolution rate within the i-th sampling period, in mol / s;

[0167] The calculation formula for the proportion of hydrogen evolution current is:

[0168]

[0169] Among them, is the proportion of hydrogen evolution current within the i-th sampling period; is the average current within the i-th sampling period, with the unit of A.

[0170] The invention discloses a real-time monitoring method for hydrogen evolution reaction of a liquid flow battery, comprising: acquiring real-time data in a battery management system; calculating the concentration of hydrogen ions in a positive electrode electrolyte in the liquid flow battery by using simultaneous equations; calculating the equilibrium mixed potential of the negative electrode according to the concentration of hydrogen ions in the positive electrode electrolyte and in combination with the equilibrium potential of the positive electrode; calculating the equilibrium potential of the negative electrode hydrogen evolution reaction according to the equilibrium mixed potential of the negative electrode; calculating the concentration of hydrogen ions in the negative electrode electrolyte according to the equilibrium potential of the negative electrode hydrogen evolution reaction; calculating the amount of hydrogen ion substance used for hydrogen evolution according to the concentration of hydrogen ions in the negative electrode electrolyte and the simultaneous equations; and calculating the amount of hydrogen gas precipitating substance according to the amount of hydrogen ion substance used for hydrogen evolution. The method for real-time monitoring of hydrogen evolution reaction in a liquid flow battery of the present invention establishes an electrochemical calculation model using real-time data of a battery management system (BMS). The method can dynamically monitor the hydrogen evolution side reaction in the liquid flow battery without the need to install a hydrogen concentration sensor, thereby eliminating the installation and maintenance costs of a hydrogen detection device and reducing costs. Based on the real-time data of the BMS, the changing trend of the hydrogen evolution side reaction can be quickly reflected, thereby improving the real-time performance of the system. The method separates the hydrogen evolution current from the main reaction current through a calculation model, thereby directly quantifying the additional consumption ratio of electrons by the side reaction, namely, the hydrogen evolution current ratio. The result is not affected by fluctuations in operating conditions such as working current density, thereby improving the reliability of system data. The method can be extended to other liquid flow batteries by only adjusting the ion expression, thereby having universality and strong compatibility.

[0171] Second implementation method:

[0172] like Figure 2 As shown, the second embodiment of the present invention provides a real-time monitoring system for hydrogen evolution reaction in a liquid flow battery, the system comprising: a data acquisition module 201, a positive electrode hydrogen ion concentration calculation module 202, a negative electrode equilibrium mixed potential calculation module 203, a negative electrode equilibrium potential calculation module 204, a negative electrode hydrogen ion concentration calculation module 205, a hydrogen ion substance amount calculation module 206, and a hydrogen gas substance amount calculation module 207.

[0173] Specifically, the data acquisition module 201 is used to acquire real-time data in the battery management system; the positive electrode hydrogen ion concentration calculation module 202 is used to calculate the hydrogen ion concentration in the positive electrode electrolyte in the liquid flow battery by using simultaneous equations; the negative electrode equilibrium mixed potential calculation module 203 is used to calculate the negative electrode equilibrium mixed potential according to the hydrogen ion concentration in the positive electrode electrolyte in combination with the positive electrode equilibrium potential; the negative electrode equilibrium potential calculation module 204 is used to calculate the equilibrium potential of the negative electrode hydrogen evolution reaction according to the negative electrode equilibrium mixed potential; the negative electrode hydrogen ion concentration calculation module 205 is used to calculate the hydrogen ion concentration in the negative electrode electrolyte according to the equilibrium potential of the negative electrode hydrogen evolution reaction; the hydrogen ion substance amount calculation module 206 is used to calculate the substance amount of hydrogen ions used for hydrogen evolution according to the hydrogen ion concentration in the negative electrode electrolyte and the simultaneous equations; the hydrogen gas substance amount calculation module 207 is used to calculate the amount of hydrogen gas precipitated according to the substance amount of hydrogen ions used for hydrogen evolution.

[0174] It is not difficult to find that this embodiment is a system embodiment corresponding to the first embodiment, and this embodiment can be implemented in cooperation with the first embodiment. The relevant technical details mentioned in the first embodiment are still valid in this embodiment. To avoid repetition, they will not be elaborated here. Correspondingly, the relevant technical details mentioned in this embodiment can also be applied in the first embodiment.

[0175] It is worth mentioning that each module involved in this embodiment is a logical module. In practical applications, a logical unit can be a physical unit, a part of a physical unit, or a combination of multiple physical units. In addition, to highlight the innovative part of the present invention, units that are not closely related to solving the technical problems proposed by the present invention are not introduced in this embodiment, but this does not mean that there are no other units in this embodiment.

[0176] The third embodiment of the present invention relates to a network-side server, such as Figure 3 shown, including at least one processor 302; and a memory 301 communicatively connected to the at least one processor 302; wherein, the memory 301 stores instructions executable by the at least one processor 302, and the instructions are executed by the at least one processor 302 to enable the at least one processor 302 to execute the above data processing method.

[0177] Among them, the memory 301 and the processor 302 are connected by a bus. The bus can include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors 302 and the memory 301 together. The bus can also connect various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art. Therefore, they will not be further described herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be an element or multiple elements, such as multiple receivers and transmitters, and provides a unit for communicating with various other devices on the transmission medium. The data processed by the processor 302 is transmitted on the wireless medium through the antenna. Further, the antenna also receives data and transmits the data to the processor 302.

[0178] The processor 302 is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interface, voltage regulation, power management, and other control functions. The memory 301 can be used to store the data used by the processor 302 when performing operations.

[0179] The fourth embodiment of the present invention relates to a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the real-time monitoring method for the hydrogen evolution reaction of the flow battery in the first embodiment.

[0180] That is, those skilled in the art can understand that all or part of the steps in the methods of the above embodiments can be completed by instructing relevant hardware through a program. The program is stored in a storage medium, including several instructions for causing a device (which can be a single-chip microcomputer, a chip, etc.) or a processor to execute all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0181] The above are only embodiments of the present invention. Common knowledge such as specific structures and characteristics known in the art are not described in detail here. Those of ordinary skill in the art know all the common general technical knowledge in the technical field to which the invention belongs before the application date or the priority date, can know all the existing technologies in this field, and have the ability to apply the conventional experimental means before this date. Those of ordinary skill in the art can, under the inspiration given in the present application, complete and implement this solution in combination with their own abilities. Some typical well-known structures or well-known methods should not become obstacles for those of ordinary skill in the art to implement the present application. It should be noted that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, and these should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicality of the patent. The protection scope required by the present application should be based on the content of its claims, and the specific implementation manners described in the specification can be used to interpret the content of the claims.

[0182] The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A real-time monitoring method for hydrogen evolution reaction in a flow battery, characterized in that, include: Get real-time data from the battery management system; The simultaneous equations are used to calculate the hydrogen ion concentration in the positive electrolyte of the flow battery; According to the concentration of hydrogen ions in the positive electrode electrolyte, the negative electrode equilibrium mixed potential is calculated in combination with the positive electrode equilibrium potential; Calculate the equilibrium potential of the negative electrode hydrogen evolution reaction based on the negative electrode equilibrium mixed potential; Calculate the hydrogen ion concentration in the negative electrode electrolyte according to the equilibrium potential of the negative electrode hydrogen evolution reaction; Calculate the amount of hydrogen ion substance used for hydrogen evolution based on the hydrogen ion concentration in the negative electrode electrolyte and the simultaneous equation; The amount of the substance that releases hydrogen is calculated based on the amount of the substance that produces hydrogen ions.

2. The real-time monitoring method for hydrogen evolution reaction of the flow battery according to claim 1, wherein The real-time data acquisition in the battery management system includes: acquiring the state of charge SOC, open circuit voltage OCV, sampling time, sampling times, acquiring the total vanadium content in the positive electrode electrolyte, monitoring the volume of the positive and negative electrode electrolytes respectively, and collecting and calculating the average temperature of the electrolyte in the positive electrode storage tank and the negative electrode storage tank of the liquid flow battery.

3. The real-time monitoring method for the hydrogen evolution reaction of the flow battery according to claim 1, characterized in that The method of calculating the hydrogen ion concentration in the positive electrolyte of a flow battery by solving simultaneous equations includes: by combining the positive hydrogen ion concentration calculation formula, the positive hydrogen ion amount conservation equation, the positive hydrogen ion amount increment calculation formula due to electrochemical reaction and migration, the positive hydrogen ion amount increment calculation formula due to dissociation equilibrium, the dissociation equilibrium equation in the positive electrolyte, and the dissociation rate calculation formula in the positive electrolyte to solve for the hydrogen ion concentration in the positive electrolyte.

4. The real-time monitoring method for hydrogen evolution reaction of the flow battery according to claim 3, characterized in that, The calculation formula for the positive electrode hydrogen ion concentration is: wherein, is the concentration of hydrogen ions in the positive electrolyte during the i-th sampling, with the unit of mol / L; is the amount of substance of hydrogen ions in the positive electrolyte during the i-th sampling, with the unit of mol; is the volume of the positive electrolyte during the i-th sampling, with the unit of L; The substance conservation equation of the positive electrode hydrogen ion is: Among them, is the amount of substance of hydrogen ions in the positive electrolyte during the (i - 1)-th sampling, with the unit of mol; is the increment of the amount of substance of hydrogen ions in the positive electrolyte during the i-th sampling period due to the battery electrochemical reaction and migration, with the unit of mol; is during the i-th sampling period in the positive electrolyte due to the increment of the amount of substance of hydrogen ions caused by the dissociation equilibrium, with the unit of mol; The calculation formula for the amount of hydrogen ion substance increment caused by the electrochemical reaction and migration of the positive electrode is: Among them, is the state of charge of the all-vanadium redox flow battery at the i-th sampling; is the state of charge of the all-vanadium redox flow battery at the (i - 1)-th sampling; is the total vanadium amount of the positive electrolyte, with the unit of mol; The positive electrode due to The calculation formula for the increment of the amount of hydrogen ions caused by the dissociation equilibrium is: Wherein, is the dissociation rate of in the positive electrolyte during the i-th sampling, with the unit of mol / (L*s); is the time interval of the i-th sampling period, with the unit of s; In the positive electrode electrolyte The dissociation equilibrium equation is: Among them, is the amount of substance of in the positive electrode electrolyte during the i-th sampling, with the unit of mol; is the amount of substance of in the positive electrode electrolyte during the (i - 1)-th sampling, with the unit of mol; In the positive electrode electrolyte The dissociation rate calculation formula is: Among them, is the rate parameter, with the unit of mol / (L*s); β is the degree of dissociation; is the activity coefficient of hydrogen ions; is the activity coefficient of 5. The real-time monitoring method for hydrogen evolution reaction of a flow battery according to claim 1, characterized in that, The negative electrode equilibrium mixed potential calculation formula is: Among them, is the negative electrode balance mixing potential of the all-vanadium redox flow battery during the i-th sampling, with the unit of V; is the open-circuit voltage of the all-vanadium redox flow battery during the i-th sampling, with the unit of V; is the positive electrode balance potential of the all-vanadium redox flow battery during the i-th sampling, with the unit of V; The calculation formula for the positive electrode equilibrium potential of all-vanadium liquid flow battery is: Among them, is the standard equilibrium potential of the positive electrode of the all-vanadium redox flow battery, which is 1.00 V; R is the gas constant, which is 8.314 J / (mol·K); is the temperature of the all-vanadium redox flow battery at the i-th sampling, with the unit of K; F is the Faraday constant, which is 96485 C / mol; is the concentration of hydrogen ions in the positive electrode electrolyte at the i-th sampling, with the unit of mol / L; is the activity coefficient of hydrogen ions; is the standard concentration, which is 1 mol / L; is the state of charge of the all-vanadium redox flow battery at the i-th sampling; is the activity coefficient of vanadium pentoxide ions in the positive electrode electrolyte; is the activity coefficient of vanadium tetraoxide ions in the positive electrode electrolyte.

6. The real-time monitoring method for hydrogen evolution reaction of the flow battery according to claim 1, wherein The equilibrium potential calculation formula of the negative electrode hydrogen evolution reaction is: Among them, is the equilibrium potential of the hydrogen evolution reaction at the negative electrode during the i-th sampling, with the unit of V; is the exchange current density of the vanadium ion reaction at the negative electrode, with the unit of A / ; is the exchange current density of the hydrogen evolution reaction at the negative electrode, with the unit of A / ; is the equilibrium potential of the vanadium ion reaction at the negative electrode during the i-th sampling, with the unit of V; is the negative electrode equilibrium mixed potential of the all-vanadium redox flow battery during the i-th sampling, with the unit of V; The calculation formula for the equilibrium potential of the negative electrode vanadium ion reaction is: Among them, is the standard equilibrium potential of the negative electrode vanadium ion reaction, which is -0.255 V; is the activity coefficient of divalent vanadium ions in the negative electrode electrolyte; is the activity coefficient of trivalent vanadium ions in the negative electrode electrolyte; R is the gas constant, which is 8.314 J / (mol·K); is the temperature of the all-vanadium redox flow battery at the i-th sampling, with the unit of K; F is the Faraday constant, which is 96485 C / mol; is the state of charge of the all-vanadium redox flow battery at the i-th sampling.

7. The real-time monitoring method for hydrogen evolution reaction of the flow battery according to claim 1, wherein The calculation formula for calculating the hydrogen ion concentration in the negative electrode electrolyte according to the equilibrium potential of the negative electrode hydrogen evolution reaction is: Among them, is the equilibrium potential of the hydrogen evolution reaction at the negative electrode during the i-th sampling, with the unit of V; R is the gas constant, which is 8.314 J / (mol·K); is the temperature of the all-vanadium redox flow battery during the i-th sampling, with the unit of K; F is the Faraday constant, which is 96485 C / mol; is the activity coefficient of hydrogen ions; is the standard concentration, which is 1 mol / L; is the concentration of hydrogen ions in the negative electrode electrolyte during the i-th sampling, with the unit of mol / L; is the standard equilibrium potential of the hydrogen evolution reaction, which is 0 V.

8. The real-time monitoring method for hydrogen evolution reaction of the flow battery according to claim 1, wherein, The method for calculating the amount of hydrogen ion substance used for hydrogen evolution according to the hydrogen ion concentration in the negative electrode electrolyte and the parallel equations includes: a calculation formula for the amount of hydrogen ion substance consumed by the negative electrode due to the hydrogen evolution side reaction, a calculation formula for the amount of hydrogen ion substance in the negative electrode electrolyte, a calculation formula for the amount of hydrogen ion substance increment caused by the migration of the negative electrode due to the electrochemical reaction, and a calculation formula for the amount of hydrogen ion substance consumed by the negative electrode due to the hydrogen evolution side reaction. The calculation formula for the amount of hydrogen ion substance increased due to dissociation equilibrium, the negative electrode electrolyte The dissociation equilibrium equation and the negative electrode electrolyte The dissociation rate calculation formula is combined to solve the amount of hydrogen ion substance used for hydrogen evolution.

9. The method for real-time monitoring of hydrogen evolution reaction in a flow battery according to claim 8, characterized in that: The calculation formula for the amount of hydrogen ion substances consumed by the negative electrode due to the hydrogen evolution side reaction is: Among them, is the amount of substance of hydrogen ions consumed due to the occurrence of the hydrogen evolution side reaction during the i-th sampling period, with the unit of mol; is the amount of substance of hydrogen ions in the negative electrode electrolyte during the (i - 1)-th sampling, with the unit of mol; is the increment of the amount of substance of hydrogen ions caused by the migration during the battery electrochemical reaction in the i-th sampling period, in mol; is during the i-th sampling period due to the increment of the amount of substance of hydrogen ions caused by the dissociation equilibrium, in mol; is the amount of substance of hydrogen ions in the negative electrode electrolyte during the i-th sampling, in mol; The calculation formula for the amount of hydrogen ion substance in the negative electrode electrolyte is: wherein, is the concentration of hydrogen ions in the negative electrode electrolyte during the i-th sampling, with the unit of mol / L; is the volume of the negative electrode electrolyte during the i-th sampling, with the unit of L; The calculation formula for the amount of hydrogen ion substance increment caused by the migration of the negative electrode due to the electrochemical reaction is: Among them, is the state of charge of the all-vanadium redox flow battery at the i-th sampling; is the state of charge of the all-vanadium redox flow battery at the (i - 1)-th sampling; is the total vanadium amount of the positive electrolyte, with the unit of mol; The negative electrode due to The calculation formula for the increment of the amount of substance of hydrogen ions caused by the dissociation equilibrium is: Among them, is the dissociation rate of in the negative electrode electrolyte during the i-th sampling, with the unit of mol / (L*s); is the time interval of the i-th sampling period, with the unit of s; In the negative electrode electrolyte The dissociation equilibrium equation is: Wherein, is the amount of substance of in the negative electrode electrolyte during the i-th sampling, with the unit of mol; is the amount of substance of in the negative electrode electrolyte during the (i - 1)-th sampling, with the unit of mol; In the negative electrode electrolyte The dissociation rate calculation formula is: Among them, is the rate parameter, with the unit of mol / (L*s); β is the degree of dissociation; is the activity coefficient of hydrogen ions; is the activity coefficient of.

10. A real-time monitoring system for hydrogen evolution reaction of a flow battery, characterized in that, The method for real-time monitoring of hydrogen evolution reaction in a liquid flow battery according to any one of claims 1 to 9, the system comprising: A data acquisition module is used to acquire real-time data in the battery management system; A positive electrode hydrogen ion concentration calculation module is used to calculate the hydrogen ion concentration in the positive electrode electrolyte in the flow battery using simultaneous equations; The negative electrode equilibrium mixed potential calculation module is used to calculate the negative electrode equilibrium mixed potential based on the hydrogen ion concentration in the positive electrode electrolyte and the positive electrode equilibrium potential; A negative electrode equilibrium potential calculation module is used to calculate the equilibrium potential of the negative electrode hydrogen evolution reaction based on the negative electrode equilibrium mixed potential; A negative electrode hydrogen ion concentration calculation module is used to calculate the hydrogen ion concentration in the negative electrode electrolyte according to the equilibrium potential of the negative electrode hydrogen evolution reaction; A hydrogen ion substance amount calculation module is used to calculate the amount of hydrogen ion substance used for hydrogen evolution according to the hydrogen ion concentration in the negative electrode electrolyte and the simultaneous equation; The hydrogen substance amount calculation module is used to calculate the amount of the substance that releases hydrogen according to the amount of the substance of the hydrogen ions used for hydrogen evolution.

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