An soc and soh joint estimation method, device and terminal equipment of a vanadium redox flow battery

Abstract

The application provides a SOC and SOH combined estimation method of a full vanadium liquid flow battery, and the method comprises the following steps: S1. constructing an equivalent circuit model, determining parameters of the equivalent circuit model as an activation polarization overpotential V act , a concentration polarization overpotential V con , a pump loss current I pump , an ohmic loss R ohm and an open circuit voltage V s ; S2. constructing a parameter calculation model based on multiple physical fields for calculating the parameters in the equivalent circuit model; S3. substituting material performance parameter values of the full vanadium liquid flow battery into the parameter calculation model to obtain a full vanadium liquid flow battery simulation model with the same or similar material performance; and S4. inputting specific size parameter values of a monitored full vanadium liquid flow battery into the parameter calculation model in step S3 to estimate the SOC and SOH of the monitored full vanadium liquid flow battery. The application improves the universality of the equivalent circuit model for various types of full vanadium liquid flow batteries, can estimate the SOC and SOH of the positive and negative half-cells respectively, and more comprehensively monitors the conditions in the actual operation process of the full vanadium liquid flow battery.

Description

Technical Field

[0001] This invention relates to a state estimation method for vanadium redox flow batteries, specifically to a method, apparatus, and terminal equipment for jointly estimating the state of charge (SOC) and state of harmonics (SOH) of vanadium redox flow batteries, belonging to the field of vanadium redox flow battery technology. Background Technology

[0002] Vanadium redox flow battery (VRB) is a highly efficient electrochemical energy storage device with advantages such as large energy storage capacity and long service life. It can effectively suppress the impact of fluctuations in new energy power generation on the power grid.

[0003] The energy storage medium of a vanadium redox flow battery (VRB) is an electrolyte containing vanadium ions, stored in an external tank. The state of charge (SOC) and state of health (SOH) of the VRB are crucial indicators during battery operation. Traditional methods for estimating SOC primarily involve constructing an equivalent circuit model and employing the ampere-hour integration method. This method has two drawbacks: first, the component parameters of the equivalent circuit model require extensive VRB experimental testing; changing the VRB model necessitates updating these parameters with new experimental results, resulting in poor versatility; second, the equivalent circuit model can only estimate SOC and cannot estimate SOH, which is crucial for operations such as mixing the positive and negative electrodes and restoring battery capacity, and is also a key indicator during battery operation. Estimating only SOC without considering SOH fails to comprehensively reflect the real-time monitoring of the VRB's operating status. Therefore, developing a universal method for real-time monitoring of the operating status of various VRB models under different scenarios is of great significance for extending VRB lifespan and promoting large-scale commercialization of VRBs. Summary of the Invention

[0004] Based on the above background, the purpose of this invention is to provide a joint estimation method for SOC and SOH of vanadium redox flow batteries. This method does not require fitting the parameters of an equivalent circuit model with experimental data, and can estimate and calculate the SOC and SOH of the positive and negative half-cells of various types of vanadium redox flow batteries separately, thereby providing a more comprehensive monitoring of the operating status of vanadium redox flow batteries.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] A method for jointly estimating the State of Charge (SOC) and State of Hypoxia (SOH) of an all-vanadium redox flow battery, comprising the following steps:

[0007] S1. Construct an equivalent circuit model and determine the parameters of the equivalent circuit model as the activation polarization overpotential V. act Concentration polarization overpotential V con Pump loss current I pump Ohmic loss Rohm and open circuit voltage V s ;

[0008] S2. Construct a multiphysics-based parameter calculation model for the parameters in the equivalent circuit model, and correspondingly calculate the continuous equation expressions for the changes in the concentrations of vanadium ions of various valences in the fuel cell stack and storage tank, and calculate the activation polarization overpotential V. act and concentration polarization overpotential V con The reaction kinetic equation expression and the calculation of ohmic loss R ohm Equation expression and calculation of open-circuit voltage V s Equation expression and calculation of pump loss current I pump The expression for the momentum equation;

[0009] S3. Substitute the material performance parameters of the vanadium redox flow battery into the parameter calculation model;

[0010] S4. Input the specific size parameter values ​​of the monitored vanadium redox flow battery into the parameter calculation model of step S3, and estimate the SOC and SOH of the monitored vanadium redox flow battery.

[0011] Preferably, in step S1, the equivalent circuit model includes a voltage source, a variable resistor, a controlled current source, and two controlled voltage sources. The voltage source, the variable resistor, and the two controlled voltage sources are connected in series and then connected in parallel with the controlled current source. One of the controlled voltage sources is used to characterize the activation polarization overpotential V caused by the electrochemical reaction during the operation of the vanadium redox flow battery. act Another controlled voltage source is used to characterize the concentration polarization overpotential V caused by electrochemical reactions during the operation of the vanadium redox flow battery. con The controlled current source is used to characterize the pump loss current I. pump The variable resistor is used to characterize the ohmic loss R caused by the fuel cell stack and electrolyte. ohm The voltage source is used to characterize the open-circuit voltage V of the vanadium redox flow battery. s .

[0012] Preferably, in step S2, the continuous equation expression for calculating the changes in the concentrations of vanadium ions of various valences in the fuel cell stack and storage tank is as follows:

[0013]

[0014]

[0015] In equations (1) and (2), Represents the i-valent vanadium ion concentrations in the fuel cell stack and storage tank, respectively; M is the number of cells connected in series; V cell V tank D represents the electrolyte volume in a single cell and a single storage tank, respectively;i Thick represents the transmembrane diffusion coefficient of i-valent ions; ed ,thick mem The thicknesses of the electrode and the film are respectively represented; z is the electron transfer number; F is the Faraday constant; I is the charging and discharging current of the battery; and Q is the electrolyte flow rate of the battery.

[0016] Calculate the activation polarization overpotential V act and concentration polarization overpotential V con The reaction kinetic equation is expressed as follows:

[0017]

[0018]

[0019] In equations (3) and (4), γ 0p ,γ 0n These are the standard reaction rate constants for the positive and negative electrodes, respectively; E 0p E 0n These are the standard potentials for the positive and negative half-cell reactions, respectively; A ed The electrode specific surface area; represents the electrode surface diffusion coefficient of vanadium ions with valence i or j, where i is 4 and j is 3 during charging (I>0) and i is 5 and j is 2 during discharging (I<0); ρ and μ are the electrolyte density and viscosity, respectively; d ed A is the average fiber diameter of the electrode; cell The cross-sectional area of ​​the fuel cell stack;

[0020] Calculate the ohmic loss R ohm The equation is expressed as follows:

[0021]

[0022] In equation (5), thick et Indicates the thickness of the half-cell; σ ed ,σ mem ,σ et These represent the conductivity of the electrode, membrane, and electrolyte, respectively.

[0023] Calculate the open-circuit voltage V s The equation is expressed as follows:

[0024]

[0025] Calculate pump loss current I pump The momentum equation is expressed as follows.

[0026]

[0027] In equation (7), ε is the electrode porosity; λ CKL is the Carman-Kozeny constant for fiber materials. pipe ,d pipe ,h pipe These represent the length, diameter, and height of the half-cell conduit, respectively; f is the total minor loss coefficient; v pipe η is the flow rate of the electrolyte in the pipe. pump For pump efficiency; U d This refers to the VRB system terminal voltage.

[0028] When using the traditional equivalent circuit model of a vanadium redox flow battery for simulation, the parameters of its circuit components need to be identified based on a large number of experimental tests. Furthermore, the component parameters of the equivalent circuit model need to be re-identified for different models of vanadium redox flow batteries. However, by using the parameter calculation model constructed based on the above expression to calculate the component parameters in the equivalent circuit model, the identification of circuit component parameters based on experimental tests can be avoided, and the concentration of vanadium ions of various valences can be calculated in real time.

[0029] Preferably, in step S3, the material performance parameter values ​​of the vanadium redox flow battery are substituted into the parameter calculation model to obtain an equation expression with the same or similar material performance values.

[0030] Preferably, in step S4, estimating the SOC and SOH of the monitored vanadium redox flow battery includes the following steps:

[0031] Construct equations for calculating SOC and SOH.

[0032]

[0033]

[0034] In equations (14) and (15), Q practical and Q theoretical These represent the actual available capacity and the theoretical available capacity, respectively; c v,p and c v,n U represents the initial vanadium ion concentrations of the positive and negative electrode electrolytes, respectively. d This is the terminal voltage of the vanadium redox flow battery.

[0035] A device for jointly estimating the state of charge (SOC) and state of harmonics (SOH) of an all-vanadium redox flow battery includes:

[0036] The first construction module is used to construct the equivalent circuit model, and the parameters of the equivalent circuit model are determined as the activation polarization overpotential V. act Concentration polarization overpotential V con Pump loss current I pump Ohmic loss R ohm and open circuit voltage V s ;

[0037] The second construction module is used to construct a multiphysics-based parameter calculation model for calculating the parameters in the equivalent circuit model, as well as the corresponding continuous equation expression for calculating the changes in the concentrations of vanadium ions of various valences in the fuel cell and storage tank, and to calculate the activation polarization overpotential V. act and concentration polarization overpotential V con The reaction kinetic equation expression and the calculation of ohmic loss R ohm Equation expression and calculation of open-circuit voltage V s Equation expression and calculation of pump loss current I pump The expression for the momentum equation;

[0038] The first calculation module is used to substitute the general fixed parameter values ​​of the vanadium redox flow battery into the parameter calculation model;

[0039] The second calculation module is used to input specific size parameter values ​​of the monitored vanadium redox flow battery into the parameter calculation model of step S3, and to estimate the SOC and SOH of the monitored vanadium redox flow battery.

[0040] A terminal device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of the method described in any of the preceding claims.

[0041] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method described in any of the preceding claims.

[0042] Compared with the prior art, the present invention has the following advantages:

[0043] This invention provides a joint estimation method for the State of Charge (SOC) and State of Hypoxia (SOH) of a vanadium redox flow battery. By using a multiphysics-based parameter calculation model and corresponding equations such as reaction kinetics, continuity, and momentum, the parameters in the equivalent circuit model are calculated without requiring extensive experimental data to fit these parameters. This improves the versatility of the equivalent circuit model for various types of vanadium redox flow batteries. Furthermore, the method can estimate the SOC and SOH of both the positive and negative half-cells separately, enabling more comprehensive monitoring of the actual operation of the vanadium redox flow battery. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0045] Figure 1 This is a schematic diagram of the joint estimation method of SOC and SOH for the all-vanadium redox flow battery of the present invention;

[0046] Figure 2 This is a schematic diagram of the equivalent circuit model and parameter calculation model of the present invention;

[0047] Figure 3 These are the charge-discharge curves obtained from simulation and experimental tests respectively using the joint estimation method of SOC and SOH for the all-vanadium redox flow battery of this invention;

[0048] Figure 4 The data represents the real-time SOC estimation data of the vanadium redox flow battery obtained through simulation testing using the joint SOC and SOH estimation method of the present invention. Detailed Implementation

[0049] The technical solution of the present invention will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings. It should be understood that the implementation of the present invention is not limited to the following embodiments, and any modifications and / or alterations made to the present invention will fall within the protection scope of the present invention.

[0050] In this invention, unless otherwise specified, all parts and percentages are by weight, and the equipment and raw materials used are commercially available or commonly used in the art. Unless otherwise specified, the methods in the following embodiments are conventional methods in the art. Unless otherwise specified, the components or equipment in the following embodiments are general standard parts or components known to those skilled in the art, and their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0051] This invention discloses a joint estimation method for the State of Charge (SOC) and State of Hypoxia (SOH) of a vanadium redox flow battery. It utilizes a multiphysics-based parameter calculation model to calculate the parameters of the equivalent circuit model. By inputting specific dimensional parameter values ​​of the monitored vanadium redox flow battery, a simulation model for a specific model of the monitored vanadium redox flow battery is formed. This model simulates the actual charge-discharge curve of the monitored vanadium redox flow battery and estimates the real-time SOC and SOH, thus achieving state monitoring of the monitored vanadium redox flow battery. This method avoids obtaining the parameters of the equivalent circuit model through extensive experiments and enables separate estimation of the SOC and SOH of the positive and negative half-cells of the vanadium redox flow battery.

[0052] The following detailed description uses a 5kW / 30kWh vanadium redox flow battery as an example, and is in conjunction with the accompanying drawings, to illustrate embodiments of the present invention. In this detailed description, many specific details are set forth for ease of explanation, providing a comprehensive understanding of the embodiments of the present invention. However, one or more embodiments may be implemented by those skilled in the art without these specific details.

[0053] like Figure 1 The method shown is a joint estimation method for SOC and SOH of an all-vanadium redox flow battery, which includes the following steps:

[0054] S1. Construct an equivalent circuit model and determine the parameters of the equivalent circuit model as the activation polarization overpotential V. act Concentration polarization overpotential V con Pump loss current I pump Ohmic loss R ohm and open circuit voltage V s ;

[0055] S2. Construct a multiphysics-based parameter calculation model for the parameters in the equivalent circuit model, and correspondingly calculate the continuous equation expressions for the changes in the concentrations of vanadium ions of various valences in the fuel cell stack and storage tank, and calculate the activation polarization overpotential V. act and concentration polarization overpotential V con The reaction kinetic equation expression and the calculation of ohmic loss R ohm Equation expression and calculation of open-circuit voltage V s Equation expression and calculation of pump loss current I pump The expression for the momentum equation;

[0056] S3. Substitute the general fixed parameter values ​​of the vanadium redox flow battery into the parameter calculation model;

[0057] S4. Input the specific size parameter values ​​of the monitored vanadium redox flow battery into the parameter calculation model of step S3, and estimate the SOC and SOH of the monitored vanadium redox flow battery.

[0058] Among them, such as Figure 2 As shown, the equivalent circuit model includes a voltage source, a variable resistor, a controlled current source, and two controlled voltage sources. The voltage source, variable resistor, and two controlled voltage sources are connected in series and then in parallel with the controlled current source. The controlled voltage source is used to characterize the activation polarization overpotential V caused by the electrochemical reaction during the operation of the vanadium redox flow battery. act Another controlled voltage source was used to characterize the concentration polarization overpotential V caused by electrochemical reactions during the operation of the all-vanadium redox flow battery. con A controlled current source is used to characterize the pump loss current I. pump The variable resistor is used to characterize the ohmic loss R caused by the fuel cell stack and electrolyte. ohm The voltage source is used to characterize the open-circuit voltage V of the vanadium redox flow battery. s .

[0059] The parameters in the equivalent circuit model constructed in step S1 are obtained by calculation using a multiphysics-based parameter calculation model. The relevant equations used in the calculation are as follows.

[0060] The continuity equation for calculating the changes in the concentrations of vanadium ions of different valences in the fuel cell stack and storage tank is as follows:

[0061]

[0062]

[0063] In equations (1) and (2), Represents the i-valent vanadium ion concentrations in the fuel cell stack and storage tank, respectively; M is the number of cells connected in series; V cell V tank D represents the electrolyte volume in a single cell and a single storage tank, respectively; i Thick represents the transmembrane diffusion coefficient of i-valent ions; ed ,thick mem The thicknesses of the electrode and the film are respectively represented; z is the electron transfer number; F is the Faraday constant; I is the charging and discharging current of the battery; and Q is the electrolyte flow rate of the battery.

[0064] Calculate the activation polarization overpotential V act and concentration polarization overpotential V con The reaction kinetic equation is expressed as follows:

[0065]

[0066]

[0067] In equations (3) and (4), γ 0p ,γ 0n These are the standard reaction rate constants for the positive and negative electrodes, respectively; E 0p E 0n These are the standard potentials for the positive and negative half-cell reactions, respectively; A ed The electrode specific surface area; represents the electrode surface diffusion coefficient of vanadium ions with valence i or j, where i is 4 and j is 3 during charging (I>0) and i is 5 and j is 2 during discharging (I<0); ρ and μ are the electrolyte density and viscosity, respectively; d ed A is the average fiber diameter of the electrode; cell The cross-sectional area of ​​the fuel cell stack;

[0068] Calculate the ohmic loss R ohm The equation is expressed as follows:

[0069]

[0070] In equation (5), thick et Indicates the thickness of the half-cell; σ ed ,σ mem ,σ etThese represent the conductivity of the electrode, membrane, and electrolyte, respectively.

[0071] Calculate the open-circuit voltage V s The equation is expressed as follows:

[0072]

[0073] Calculate pump loss current I pump The momentum equation is expressed as follows.

[0074]

[0075] In equation (7), ε is the electrode porosity; λ CK L is the Carman-Kozeny constant for fiber materials. pipe ,d pipe ,h pipe These represent the length, diameter, and height of the half-cell conduit, respectively; f is the total minor loss coefficient; v pipe η is the flow rate of the electrolyte in the pipe. pump For pump efficiency; U d This refers to the VRB system terminal voltage.

[0076] The material performance parameters of the all-vanadium redox flow battery are shown in Table 1.

[0077] Table 1 Material performance parameters of vanadium redox flow batteries

[0078]

[0079]

[0080] After substituting the material performance parameters of the all-vanadium redox flow battery in Table 1 into the parameter calculation model, the following equation expression with general fixed parameter values ​​for materials with the same or similar properties is obtained:

[0081] The continuity equation for calculating the changes in the concentrations of vanadium ions of different valences in the fuel cell stack and storage tank is as follows:

[0082]

[0083] Calculate the activation polarization overpotential V act and concentration polarization overpotential V con The reaction kinetic equation is expressed as follows:

[0084]

[0085]

[0086] Calculate the ohmic loss R ohm The equation is expressed as follows:

[0087] R ohm =4.17×10 -4 M(29)

[0088] Calculate the open-circuit voltage V s The equation is expressed as follows:

[0089]

[0090] Calculate pump loss current I pump The momentum equation is expressed as follows.

[0091]

[0092] The specific size parameter values ​​of the monitored vanadium redox flow battery are input into the parameter calculation model with general fixed parameter values ​​that have the same or similar material properties. In this embodiment, the specific size parameter values ​​of the monitored vanadium redox flow battery are shown in Table 2.

[0093] Table 2 Specific Dimensional Parameters of Vanadium Redox Flow Batteries

[0094]

[0095]

[0096] Input the parameter values ​​in Table 2 into the parameter calculation model with general fixed parameter values ​​to obtain a model adapted to the monitored vanadium redox flow battery model.

[0097] Estimating the SOC and SOH of the monitored vanadium redox flow cell includes the following steps: constructing equations for calculating SOC and SOH.

[0098]

[0099]

[0100] In equations (14) and (15), Q practical and Q theoretical These represent the actual available capacity and the theoretical available capacity, respectively; c v, p and c v, n represents the initial vanadium ion concentration in the positive and negative electrode electrolytes, respectively, and U d This is the terminal voltage of the vanadium redox flow battery.

[0101] Simulations and tests were conducted under the conditions of temperature T = 25℃, charge / discharge current I = 80A, and electrolyte flow rate Q = 32L / min. The effectiveness of the method was verified by comparing the simulation data and experimental data. The charge / discharge curves of the monitored vanadium redox flow battery, plotted based on the simulation and experimental data, are shown below. Figure 3As shown in the figure, the simulation results of the SOC change of the monitored all-vanadium redox flow battery over time are as follows: Figure 4 As shown, the simulated SOH of the monitored vanadium redox flow battery is 92.399%.

[0102] The above tests show that the simulation estimation of the monitored vanadium redox flow battery using the joint estimation method of SOC and SOH, compared with the actual experiment, shows that the charge-discharge curves of the two methods are basically consistent, thus verifying the accuracy of the method. Furthermore, this method can estimate the SOC and SOH of both the positive and negative half-cells separately, thereby providing a more comprehensive monitoring of the actual operation of the vanadium redox flow battery.

[0103] Embodiments of the present invention also disclose a joint estimation device for SOC and SOH of an all-vanadium redox flow battery, comprising a first construction module, a second construction module, a first calculation module, and a second calculation module. The first construction module is used to construct an equivalent circuit model and determine the parameters of the equivalent circuit model as the activation polarization overpotential V. act Concentration polarization overpotential V con Pump loss current I pump Ohmic loss R ohm and open circuit voltage V s The second building module is used to construct a multiphysics-based parameter calculation model for calculating the parameters in the equivalent circuit model, as well as the corresponding continuous equation expression for calculating the changes in the concentrations of vanadium ions of various valences in the fuel cell stack and storage tank, and to calculate the activation polarization overpotential V. act and concentration polarization overpotential V con The reaction kinetic equation expression and the calculation of ohmic loss R ohm Equation expression and calculation of open-circuit voltage V s Equation expression and calculation of pump loss current I pump The momentum equation expression is given. The first calculation module is used to substitute the general fixed parameter values ​​of the vanadium redox flow battery into the parameter calculation model. The second calculation module is used to input the specific size parameter values ​​of the monitored vanadium redox flow battery into the parameter calculation model of step S3, and estimate the SOC and SOH of the monitored vanadium redox flow battery.

[0104] Embodiments of the present invention also disclose a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method described above.

[0105] Embodiments of the present invention also disclose a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method described above.

[0106] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for jointly estimating the State of Charge (SOC) and State of Hypoxia (SOH) of an all-vanadium redox flow battery, characterized in that: The method includes the following steps: S1. Construct an equivalent circuit model and determine the parameters of the equivalent circuit model as the activation polarization overpotential V. act Concentration polarization overpotential V con Pump loss current I pump Ohmic loss R ohm and open circuit voltage V s ; S2. Construct a multiphysics-based parameter calculation model for calculating the parameters in the equivalent circuit model. This parameter calculation model includes a continuous equation expression for calculating the changes in the concentrations of vanadium ions of various valences in the fuel cell stack and storage tank, and for calculating the activation polarization overpotential. and concentration polarization overpotential The reaction kinetic equation expression and the calculation of ohmic loss R ohm Equation expression and calculation of open-circuit voltage V s Equation expression and calculation of pump loss current I pump The expression for the momentum equation; S3. Substitute the material performance parameter values ​​of the vanadium redox flow battery into the parameter calculation model to obtain the equation expression with the same or similar material performance; S4. Input the specific size parameter values ​​of the monitored vanadium redox flow battery into the parameter calculation model of step S3, and estimate the SOC and SOH of the monitored vanadium redox flow battery, including the following steps: Construct equations for calculating SOC and SOH. ， ， In equations (14) and (15), and These represent the actual available capacity and the theoretical available capacity, respectively. and These represent the initial vanadium ion concentrations in the positive and negative electrode electrolytes, respectively. This is the terminal voltage of the vanadium redox flow battery. This indicates the concentration of i-valent vanadium ions in the storage tank.

2. The method for jointly estimating the SOC and SOH of an all-vanadium redox flow battery according to claim 1, characterized in that: In step S1, the equivalent circuit model includes a voltage source, a variable resistor, a controlled current source, and two controlled voltage sources. The voltage source, the variable resistor, and the two controlled voltage sources are connected in series and then connected in parallel with a controlled current source. One of the controlled voltage sources is used to characterize the activation polarization overpotential V caused by the electrochemical reaction during the operation of the vanadium redox flow battery. act Another controlled voltage source is used to characterize the concentration polarization overpotential V caused by electrochemical reactions during the operation of the vanadium redox flow battery. con The controlled current source is used to characterize the pump loss current I. pump The variable resistor is used to characterize the ohmic loss R caused by the fuel cell stack and electrolyte. ohm The voltage source is used to characterize the open-circuit voltage V of the vanadium redox flow battery. s .

3. The method for jointly estimating the SOC and SOH of an all-vanadium redox flow battery according to claim 1, characterized in that: In step S2, the continuity equation expression for calculating the changes in the concentrations of vanadium ions of various valences in the fuel cell stack and storage tank is as follows: ， ， In equations (1) and (2), This represents the concentration of i-valent vanadium ions in the fuel cell stack; M is the number of cells connected in series. These represent the electrolyte volumes in a single cell and a single storage tank, respectively. This represents the transmembrane diffusion coefficient of i-valent ions; The thicknesses of the electrode and the film are respectively represented; z is the electron transfer number; F is the Faraday constant; I is the charging and discharging current of the battery; and Q is the electrolyte flow rate of the battery. Calculate activation polarization overpotential and concentration polarization overpotential The reaction kinetic equation is expressed as follows: ， ， In equations (3) and (4), These are the standard reaction rate constants at the positive and negative electrodes, respectively. These are the standard potentials for the positive and negative half-cell reactions, respectively. The electrode specific surface area; The electrode surface diffusion coefficient represents i or j vanadium ions, with i taking 4 and j taking 3 during charging (I>0) and i taking 5 and j taking 2 during discharging (I<0); These are the electrolyte density and viscosity, respectively. The average fiber diameter of the electrode; The cross-sectional area of ​​the fuel cell stack; Calculate the ohmic loss R ohm The equation is expressed as follows: ， In equation (5), Indicates the thickness of a half-cell; These represent the conductivity of the electrode, membrane, and electrolyte, respectively. Calculate the open-circuit voltage V s The equation is expressed as follows: ， Calculate pump loss current I pump The momentum equation is expressed as follows. ， In equation (7), Electrode porosity; The Carman-Kozeny constant for fiber materials; , where are the length, diameter, and height of the half-cell pipe, respectively; f is the total minor loss coefficient; The flow rate of the electrolyte in the pipeline; For pump efficiency; This refers to the VRB system terminal voltage.

4. A device for jointly estimating the state of charge (SOC) and state of harmonics (SOH) of an all-vanadium redox flow battery, characterized in that: The joint estimation device for SOC and SOH of the all-vanadium redox flow battery includes: The first construction module is used to construct the equivalent circuit model, and the parameters of the equivalent circuit model are determined as the activation polarization overpotential V. act Concentration polarization overpotential V con Pump loss current I pump Ohmic loss R ohm and open circuit voltage V s ; The second construction module is used to construct a multiphysics-based parameter calculation model for calculating the parameters in the equivalent circuit model. This parameter calculation model includes a continuous equation expression for calculating the changes in the concentrations of vanadium ions of various valences in the fuel cell stack and storage tank, and for calculating the activation polarization overpotential. and concentration polarization overpotential The reaction kinetic equation expression and the calculation of ohmic loss R ohm Equation expression and calculation of open-circuit voltage V s Equation expression and calculation of pump loss current I pump The expression for the momentum equation; The first calculation module is used to substitute the general fixed parameter values ​​of the vanadium redox flow battery into the parameter calculation model to obtain the equation expression with the same or similar material properties. The second calculation module is used to input specific size parameter values ​​of the monitored vanadium redox flow battery into the parameter calculation model of step S3, and to estimate the SOC and SOH of the monitored vanadium redox flow battery, including the following steps: Construct equations for calculating SOC and SOH. ， ， In equations (14) and (15), and These represent the actual available capacity and the theoretical available capacity, respectively. and These represent the initial vanadium ion concentrations in the positive and negative electrode electrolytes, respectively. This is the terminal voltage of the vanadium redox flow battery. This indicates the concentration of i-valent vanadium ions in the storage tank.

5. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1-3.

6. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1-3.

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