Proton exchange membrane water electrolysis hydrogen production electrochemical kinetics correction calculation method

Abstract

The invention discloses a proton exchange membrane water electrolysis hydrogen production electrochemical kinetics correction calculation method. The method comprises the following steps: S1, model assumption; s2, constructing an electrochemical model; S2.1, solving two charge balance equations in an electron conduction domain and an electrolyte domain, and completing coupling calculation of potential distribution and electrochemical kinetics; s2.2, introducing the volume fraction and the stoichiometric coefficient of each component into an equilibrium potential equation and a Butler-Volmer equation to complete the correction of the equations, and establishing a corrected PEMWE three-dimensional simulation model; and S3, verifying the accuracy of the corrected PEMWE three-dimensional simulation model and the calculation method. According to the electrochemical kinetics correction calculation method for hydrogen production through water electrolysis of the proton exchange membrane, electrochemical kinetics calculation of the electrolytic tank is corrected, and the problem that the electrochemical reaction rate of the electrolytic tank is affected by the concentration of reactants in actual calculation is solved.

Description

Technical Field

[0001] This invention belongs to the field of PEM electrolyzer technology, specifically relating to a corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis for hydrogen production. Background Technology

[0002] Proton exchange membrane water electrolysis (PEMWE) technology boasts advantages such as high current density, high energy conversion efficiency, and good adaptability to renewable energy sources, making it a cutting-edge research direction in the field of large-scale energy storage. However, PEMWE requires expensive precious metal catalysts and operates at high current densities (1 A / cm²). 2 The harsh environment, characterized by strong acidity, multi-component gas, and non-uniform distribution of heat and electricity, leads to high investment costs and rapid electrode performance degradation, severely hindering its commercialization. Therefore, reducing costs and ensuring the long-term stable operation of the electrolyzer has become the primary research task.

[0003] For a long time, PEMWE research has mainly focused on the design and control of materials, neglecting the heat and mass transfer processes within the membrane electrode. In past work, researchers have obtained the trends of parameters such as the electrolyzer operating temperature, inlet and outlet water temperatures, and interlayer local temperature under different operating conditions through various experimental methods. However, due to the complexity of CCM technology and structure, online measurement of the temperature distribution in the micro-regions of the membrane electrode still faces significant challenges. Furthermore, current experimental research mainly focuses on low current densities (0~2 A / cm²). 2 The operating range is limited, but to meet the needs of large-scale hydrogen production and commercialization, PEMWE requires a high current density (2.0 A / cm²). 2 (Above) High-efficiency and stable operation will be a major development trend for PEMWE in the future. However, under high current density operating conditions, the CCM region involves heterogeneous electrochemical reactions, and mass transfer mechanisms such as heat transfer, convection, and gas diffusion exhibit distinctly different thermal coupling characteristics. Therefore, it is urgent to conduct in-depth research on the thermal coupling characteristics of the PEMWE film electrode region under high current density.

[0004] While existing experimental methods are important for studying the internal temperature variations of electrolyzers under different operating conditions, they struggle to quantitatively describe the thermal coupling characteristics within the complex structure of the membrane electrode assembly (MEA). In contrast, the finite element method (FEM) and finite volume method, developed in recent years, discretize the three-dimensional PEMWE model in time and space, and based on solving partial differential equations, can reveal the distribution patterns of key physical quantities such as electrochemical reactions, gas-liquid two-phase flow, and heat transfer. Although many three-dimensional, two-phase, steady-state multiphysics PEMWE simulation models have been developed to calculate the reactions and heat and mass transfer processes within the electrolyzer, these models often directly borrow from relatively well-established fuel cell models to construct electrode reaction kinetics and directly modify the Butler-Volmer equation using the liquid water saturation index. This makes it difficult to reveal the interaction mechanism between gas-liquid transport and electrochemical reaction characteristics on the PEMWE electrode surface under real-world service conditions. Summary of the Invention

[0005] The purpose of this invention is to provide a corrected calculation method for the electrochemical kinetics of proton exchange membrane water electrolysis for hydrogen production. Based on the classical electrochemical reaction kinetics theory, an innovative 3D, two-phase, non-isothermal multiphysics theoretical analysis model based on gas phase volume fraction correction is developed. This model reveals the influence of heat transfer, mass transfer, and electrode electrochemical reaction processes on the thermal coupling characteristics of the electrode surface, corrects the electrochemical kinetics calculation of the electrolytic cell, and solves the problem that the electrochemical reaction rate of the electrolytic cell is affected by the reactant concentration in practical calculations.

[0006] The technical solution adopted in this invention is: a corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis for hydrogen production, the specific method of which is as follows:

[0007] S1. Model Assumptions: Make reasonable assumptions and simplifications when building the model; S2. Constructing an electrochemical model: S2.1 Solve the two charge balance equations in the electronic conduction domain and the electrolyte domain to complete the coupled calculation of potential distribution and electrochemical kinetics; S2.2, Calculate the volume fraction of each component. s i and stoichiometric coefficients n i The equilibrium potential equation and the Butler-Volmer equation are introduced, the Butler-Volmer equation is modified, and the modified PEMWE three-dimensional simulation model is established. S3. Verify the accuracy of the corrected PEMWE 3D simulation model and calculation method: Build a PEMWE single-cell test system to verify the accuracy of the constructed electrochemical model.

[0008] The invention is further characterized by: The specific assumptions made in S1 are as follows: The water inside the electrolytic cell exists in liquid form, and the phase change process of water is ignored; All gases are considered to be incompressible ideal gases; Ignore the cross-permeability of hydrogen and oxygen in the proton exchange membrane; The anode catalyst layer, cathode catalyst layer, anode porous transport layer, cathode porous transport layer, and PEM are all homogeneous structures and are isotropic. Ignore the contact resistance and thermal resistance between all adjacent components.

[0009] The specific method for S2.1 is as follows: The solid-phase potential and electrolyte potential of proton exchange membrane electrolysis in water are calculated based on the following equations: (1) (2) In the formula, d s The solid-state conductivity is expressed in S / m. i The overpotential is V; R i As a local current source, A / m 3 ; d m Proton conductivity, S / m, is determined by temperature and water content. l The function, where l Defined as the ratio of the number of water molecules to the number of charged nodes: (3) Equilibrium potential E eq (V) is defined by the Nernst equation as: (4) In the formula, n The number of electrons participating in the electrode reaction; F This is the Faraday constant, with a value of 96485 C / mol; R This is the universal gas constant; T To calculate the temperature at each point within the domain, the unit is... K ; C R and C O It is a dimensionless expression describing the concentration dependence of the oxidized and reduced substances in the reaction; The current density at the electrode and cathode in proton exchange membrane electrolysis of water is related to the local concentration of each substance participating in the reaction on the electrode surface, and is defined as: (5) In the formula, i 0 represents the exchange current density, with units of A / m. 2 ; α a and α c These are the charge transfer coefficients of the anode and cathode, respectively. α a + α c = n , or The activation overpotential is expressed in V.

[0010] In the above formula (4), the reference equilibrium potential for each electrode reaction is... E eq,ref( T ), which can be determined by the standard free energy Δ H and reaction entropy Δ S The calculation shows that: (6).

[0011] Activation overpotential or Defined as: (7) Taking electron transfer into account, the electrochemical reaction equation is expressed as: (8) In the formula, n i is the stoichiometric coefficient of the reactants.

[0012] The specific method for S2.2 is as follows: The volume fraction of each component s i and stoichiometric coefficient ν i Introducing the equilibrium potential equation and the Butler-Volmer equation, using s i νi Indicate C i Substituting equations (4) and (5), we can obtain the following expression: (9) (10) (11) (12).

[0013] The PEMWE single-cell testing system in S3 uses a commercial CCM, specifically: IrO2 2.2 mg / cm³. 2 Pt / C 1.2 mg / cm 2Nafion 115 has an active surface area of ​​6.25 cm². 2 The anode and cathode PTLs are made of titanium felt and Toray 060 carbon paper, respectively. The titanium felt is 250 μm thick and has a porosity of 65%, while the Toray 060 carbon paper is 192 μm thick and has a porosity of 78%. Both the cathode and anode are made of titanium plates with parallel flow channels. The flow channel plates are clamped by two stainless steel end plates and tightened by eight evenly distributed M6 bolts with a torque of 5 N·m. To prevent leakage, PTFE is used for interlayer sealing. The PEMWE single-cell testing system includes a DC power supply, a water tank, a peristaltic pump, an electrolytic cell, an electric heater, and connecting pipelines.

[0014] The specific methods for the testing process in S3 are as follows: During the test, a DC power supply provides current to the electrolytic cell, and the power of the electric heater is adjusted by PID control to ensure a constant inlet water temperature in the electrolytic cell. Deionization is supplied to the anode of the electrolytic cell by a peristaltic pump at a flow rate of 15 mL / min. The deionization resistivity is >18.2 MΩ·cm. The generated H2 and O2 are discharged into the external environment through the connecting pipeline, and the carried outlet water is returned to the water tank through the separator to complete one cycle. To remove residual impurities introduced during the CCM manufacturing process, an electrolytic cell activation process is performed before each experimental test, and the entire activation process lasts for 12 hours. During the experiment, the electrolysis current density was changed by adjusting the DC power supply. Each data acquisition required the system to run stably for more than 180 seconds, and the current and voltage were recorded in the last 60 seconds. All tests were conducted under the conditions of an inlet water temperature of 65℃ and a back pressure of atmospheric pressure.

[0015] The beneficial effects of this invention are: (1) The electrochemical kinetics correction calculation method for proton exchange membrane electrolysis of water to produce hydrogen in this invention proposes an electrode reaction theoretical model corrected by stoichiometry and saturation, which significantly improves the prediction accuracy of the internal temperature distribution of the electrolysis cell and reveals the evolution law of the thermal coupling characteristics of the membrane electrode region, namely: for the PEMWE electrolysis hydrogen production process, the volume fractions of each component s i and stoichiometric coefficient ν i Introducing the equilibrium potential equation and the Butler-Volmer equation, using s i νi Indicate C i The experimental results and numerical simulation results show consistent trends with small deviations, indicating that the model and method established by numerical simulation can well predict the actual electrochemical performance of PEMWE electrolyzers. (2) Based on the classical electrochemical reaction kinetics formula, this invention modifies the Butler-Volme equation to describe the different electrochemical reaction processes of the anode and cathode respectively. It can significantly improve the calculation accuracy in evaluating the performance of the electrolytic cell, provide a new research idea for a deeper understanding of the heat transfer process inside the electrolytic cell, and has strong practical guiding significance. Attached Figure Description

[0016] Figure 1 is a diagram of the experimental testing system of the PEMWE single-cell testing system of the present invention; Figure 2 is a physical diagram of the PEMWE single-cell testing system of the present invention; Figure 3 shows the polarization curves obtained from experiments and numerical calculations during the PEMWE electrolysis hydrogen production process of this invention. Schematic diagram; Figure 4 is a schematic diagram of the changes in the outlet water temperature of the electrolyzer during the PEMWE electrolysis hydrogen production process of this invention, based on experimental and numerical calculations. Detailed Implementation

[0017] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0018] The present invention provides a corrected calculation method for the electrochemical kinetics of proton exchange membrane water electrolysis for hydrogen production. The specific method is as follows: S1. Model Assumptions: Reasonable assumptions and simplifications are made when building the model; the specific assumptions are as follows: 1) The water inside the electrolytic cell exists in liquid form, and the phase change process of water is ignored; 2) All gases are considered to be incompressible ideal gases; 3) Ignore the cross-permeation of hydrogen and oxygen in the proton exchange membrane; 4) The anodic catalyst layer (ACL), the cathode catalyst layer (CCL), the anode porous transport layer (APTL), the cathode porous transport layer (CPTL), and the PEM are all homogeneous structures and are isotropic; 5) Ignore the contact resistance and thermal resistance between all adjacent components.

[0019] S2. Constructing an electrochemical model: S2.1 The driving force of the electrochemical reaction is the potential difference between the solid phase and the electrolyte phase. By solving the two charge balance equations in the electronic conduction domain and the electrolyte domain, the coupled calculation of potential distribution and electrochemical kinetics can be achieved. Among them, the solid phase potential and electrolyte potential of proton exchange membrane electrolysis of water are calculated according to the following equations: (1) (2) In the formula, ds The solid-state conductivity is expressed in S / m. i overpotential (corresponding to) s and m ), V; R i Local current source (corresponding to) R s and R m ), A / m 3 ; d m Proton conductivity, S / m, is determined by temperature and water content. l The function, where l Defined as the ratio of the number of water molecules to the number of charged nodes: (3) Equilibrium potential E eq (V) is defined by the Nernst equation as: (4) In the formula, n The number of electrons participating in the electrode reaction; F This is the Faraday constant, with a value of 96485 C / mol; R This is the universal gas constant; T To calculate the temperature at each point within the domain, the unit is... K ; C R and C O It is a dimensionless expression describing the concentration dependence of the oxidized and reduced substances in the reaction; The current density at the electrode and cathode in proton exchange membrane electrolysis of water is related to the local concentration of each substance participating in the reaction on the electrode surface, and is defined as: (5) In the formula, i 0 represents the exchange current density, with units of A / m. 2 ; α a and α c These are the charge transfer coefficients of the anode and cathode, respectively. α a + α c = n , or The activation overpotential is expressed in V.

[0020] In formula (4), the reference equilibrium potential for each electrode reaction is... Eeq,ref( T ), which can be determined by the standard free energy Δ H and reaction entropy Δ S The calculation shows that: (6).

[0021] Activation overpotential or Defined as: (7) Taking electron transfer into account, the electrochemical reaction equation is expressed as: (8) In the formula, n i is the stoichiometric coefficient of the reactants.

[0022] S2.2, Calculate the volume fraction of each component. s i and stoichiometric coefficients n i The equilibrium potential equation and the Butler-Volmer equation are introduced, the Butler-Volmer equation is modified, and the modified PEMWE three-dimensional simulation model is established. In PEMWE simulations, concentration theory is no longer directly applicable to calculating the effect of gas-liquid phases on electrochemical rates. Considering that chemical reaction rates are influenced by both temperature and reactant concentration, the liquid water saturation s is typically introduced directly into the Butler-Volmer equation as a coefficient. However, this method lacks theoretical and practical support. Therefore, based on the theory of the effect of concentration on electrochemical rates, this application uses the volume fraction of each component... s i and stoichiometric coefficients n i The equilibrium potential equation and the Butler-Volmer equation are introduced, as follows: The volume fractions and stoichiometric coefficients of each component are introduced into the equilibrium potential equation and the Butler-Volmer equation, using s i νi Indicate C i Substituting equations (4) and (5), we can obtain the following expression: (9) (10) (11) (12).

[0023] By establishing a modified PEMWE three-dimensional simulation model, a corrected calculation method for the electrochemical kinetics of proton exchange membrane water electrolysis to produce hydrogen is obtained, which can make the calculation results more accurate.

[0024] S3. Verify the accuracy of the corrected PEMWE 3D simulation model and calculation method: Build a PEMWE single-cell test system to verify the accuracy of the constructed electrochemical model.

[0025] Furthermore, to verify the accuracy of the model and calculation method, a PEMWE single-cell testing system was built. The structural dimensions of each part are consistent with the physical model. The PEMWE single-cell testing system uses a commercial CCM, specifically: IrO2 2.2 mg / cm³. 2 Pt / C 1.2 mg / cm 2 Nafion 115 has an active surface area of ​​6.25 cm². 2 The anode and cathode PTLs are made of titanium felt and Toray 060 carbon paper, respectively. The titanium felt is 250 μm thick and has a porosity of 65%, while the Toray 060 carbon paper is 192 μm thick and has a porosity of 78%. Both the cathode and anode are made of titanium plates with parallel flow channels. The flow channel plates are clamped by two stainless steel end plates on the outside and tightened by eight evenly distributed M6 bolts with a torque of 5 N·m. To prevent leakage, PTFE is used for interlayer sealing. like Figure 1 and Figure 2 The diagrams show the experimental testing system and its physical components, including a DC power supply, water tank, peristaltic pump, electrolytic cell, electric heater, and connecting pipes.

[0026] The specific methods for the testing process are as follows: During the test, a DC power supply provides current to the electrolytic cell, and the power of the electric heater is adjusted by PID control to ensure a constant inlet water temperature in the electrolytic cell. Deionization is supplied to the anode of the electrolytic cell by a peristaltic pump at a flow rate of 15 mL / min. The deionization resistivity is >18.2 MΩ·cm. The generated H2 and O2 are discharged into the external environment through the connecting pipeline, and the carried outlet water is returned to the water tank through the separator to complete one cycle. To remove residual impurities introduced during the CCM manufacturing process, an electrolytic cell activation process is performed before each experimental test, and the entire activation process lasts for about 12 hours. During the experiment, the electrolysis current density was changed by adjusting the DC power supply. Each data acquisition required the system to run stably for more than 180 seconds, and the current and voltage were recorded in the last 60 seconds. All tests were conducted under the conditions of an inlet water temperature of 65℃ and a back pressure of atmospheric pressure.

[0027] For the PEMWE electrolysis hydrogen production process, Figure 3The changes in polarization curves from both experimental and numerical calculations are presented. Figure 4 The changes in the outlet water temperature of the electrolyzer are presented in both experimental and numerical simulations. The results show that the experimental and numerical simulation results are consistent with each other, with minimal deviation. This indicates that the model and method established through numerical simulation can accurately predict the actual electrochemical performance of the PEMWE electrolyzer.

[0028] Example 1 The corrected calculation method for the electrochemical kinetics of proton exchange membrane water electrolysis for hydrogen production in this embodiment is as follows: S1. Model Assumptions: Make reasonable assumptions and simplifications when building the model; S2. Constructing an electrochemical model: S2.1 Solve the two charge balance equations in the electronic conduction domain and the electrolyte domain to complete the coupled calculation of potential distribution and electrochemical kinetics; S2.2, Calculate the volume fraction of each component. s i and stoichiometric coefficients n i The equilibrium potential equation and the Butler-Volmer equation are introduced, the Butler-Volmer equation is modified, and the modified PEMWE three-dimensional simulation model is established. S3. Verify the accuracy of the corrected PEMWE 3D simulation model and calculation method: Build a PEMWE single-cell test system to verify the accuracy of the constructed electrochemical model.

[0029] Example 2 The corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis to produce hydrogen in this embodiment further includes the following specific assumptions made in S1: 1) The water inside the electrolytic cell exists in liquid form, and the phase change process of water is ignored; 2) All gases are considered to be incompressible ideal gases; 3) Ignore the cross-permeation of hydrogen and oxygen in the proton exchange membrane; 4) The anodic catalyst layer (ACL), the cathode catalyst layer (CCL), the anode porous transport layer (APTL), the cathode porous transport layer (CPTL), and the PEM are all homogeneous structures and are isotropic; 5) Ignore the contact resistance and thermal resistance between all adjacent components.

[0030] Example 3 The electrochemical kinetics correction calculation method for proton exchange membrane water electrolysis to produce hydrogen in this embodiment is further described in S2.1 as follows: The solid-phase potential and electrolyte potential of proton exchange membrane electrolysis in water are calculated based on the following equations: (1) (2) In the formula, d s The solid-state conductivity is expressed in S / m. i overpotential (corresponding to) s and m ), V; R i Local current source (corresponding to) R s and R m ), A / m 3 ; d m Proton conductivity, S / m, is determined by temperature and water content. l The function, where l Defined as the ratio of the number of water molecules to the number of charged nodes: (3) Equilibrium potential E eq (V) is defined by the Nernst equation as: (4) In the formula, n The number of electrons participating in the electrode reaction; F This is the Faraday constant, with a value of 96485 C / mol; R This is the universal gas constant; T To calculate the temperature at each point within the domain, the unit is... K ; C R and C O It is a dimensionless expression describing the concentration dependence of the oxidized and reduced substances in the reaction; The current density at the electrode and cathode in proton exchange membrane electrolysis of water is related to the local concentration of each substance participating in the reaction on the electrode surface, and is defined as: (5) In the formula, i 0 represents the exchange current density, with units of A / m. 2 ; α a and α c These are the charge transfer coefficients of the anode and cathode, respectively. α a + α c = n, or The activation overpotential is expressed in V.

[0031] In formula (4), the reference equilibrium potential for each electrode reaction is... E eq,ref( T ), which can be determined by the standard free energy Δ H and reaction entropy Δ S The calculation shows that: (6).

[0032] Activation overpotential or Defined as: (7) Taking electron transfer into account, the electrochemical reaction equation is expressed as: (8) In the formula, n i is the stoichiometric coefficient of the reactants.

[0033] Example 4 The corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis to produce hydrogen in this embodiment is further described in S2.2 as follows: The volume fraction of each component s i and stoichiometric coefficient ν i Introducing the equilibrium potential equation and the Butler-Volmer equation, using s i νi Indicate C i Substituting equations (4) and (5), we can obtain the following expression: (9) (10) (11) (12).

[0034] Example 5 In this embodiment, the electrochemical kinetics correction calculation method for proton exchange membrane water electrolysis to produce hydrogen is used. Furthermore, the PEMWE single-cell testing system in S3 uses a commercial CCM, specifically with IrO2 2.2 mg / cm³. 2 Pt / C 1.2 mg / cm 2 Nafion115 has an active surface area of ​​6.25 cm². 2The anode and cathode PTLs are made of titanium felt and Toray 060 carbon paper, respectively. The titanium felt is 250 μm thick and has a porosity of 65%, while the Toray 060 carbon paper is 192 μm thick and has a porosity of 78%. Both the cathode and anode are made of titanium plates with parallel flow channels. The flow channel plates are clamped by two stainless steel end plates and tightened by eight evenly distributed M6 bolts with a torque of 5 N·m. To prevent leakage, PTFE is used for interlayer sealing. like Figure 1 and Figure 2 The experimental test system diagram and physical diagram include a DC power supply, water tank, peristaltic pump, electrolytic cell, electric heater, and connecting pipelines.

[0035] Example 6 The corrected calculation method for the electrochemical kinetics of proton exchange membrane water electrolysis for hydrogen production in this embodiment, and further, the specific testing method are as follows: During the test, a DC power supply provides current to the electrolytic cell, and the power of the electric heater is adjusted by PID control to ensure a constant inlet water temperature in the electrolytic cell. Deionization is supplied to the anode of the electrolytic cell by a peristaltic pump at a flow rate of 15 mL / min. The deionization resistivity is >18.2 MΩ·cm. The generated H2 and O2 are discharged into the external environment through the connecting pipeline, and the carried outlet water is returned to the water tank through the separator to complete one cycle. To remove residual impurities introduced during the CCM manufacturing process, an electrolytic cell activation process is performed before each experimental test, and the entire activation process lasts for about 12 hours. During the experiment, the electrolysis current density was changed by adjusting the DC power supply. Each data acquisition required the system to run stably for more than 180 seconds, and the current and voltage were recorded in the last 60 seconds. All tests were conducted under the conditions of an inlet water temperature of 65℃ and a back pressure of atmospheric pressure.

[0036] For the PEMWE electrolysis hydrogen production process, Figure 3 The changes in polarization curves from both experimental and numerical calculations are presented. Figure 4 The changes in the outlet water temperature of the electrolyzer are presented in both experimental and numerical simulations. The results show that the experimental and numerical simulation results are consistent with each other, with minimal deviation. This indicates that the model and method established through numerical simulation can accurately predict the actual electrochemical performance of the PEMWE electrolyzer.

Claims

1. A corrected calculation method for electrochemical kinetics of hydrogen production via proton exchange membrane water electrolysis, characterized in that, The specific method is as follows: S1. Model Assumptions: Make reasonable assumptions and simplifications when building the model; S2. Constructing an electrochemical model: S2.1 Solve the two charge balance equations in the electronic conduction domain and the electrolyte domain to complete the coupled calculation of potential distribution and electrochemical kinetics; S2.2, Calculate the volume fraction of each component. s i and stoichiometric coefficients ν i The equilibrium potential equation and the Butler-Volmer equation are introduced, the Butler-Volmer equation is modified, and the modified PEMWE three-dimensional simulation model is established. S3. Verify the accuracy of the corrected PEMWE 3D simulation model and calculation method: Build a PEMWE single-cell test system to verify the accuracy of the constructed electrochemical model.

2. The corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis to produce hydrogen according to claim 1, characterized in that, The specific assumptions made in S1 are as follows: The water inside the electrolytic cell exists in liquid form, and the phase change process of water is ignored; All gases are considered to be incompressible ideal gases; Ignore the cross-permeability of hydrogen and oxygen in the proton exchange membrane; The anode catalyst layer, cathode catalyst layer, anode porous transport layer, cathode porous transport layer, and PEM are all homogeneous structures and are isotropic. Ignore the contact resistance and thermal resistance between all adjacent components.

3. The corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis to produce hydrogen according to claim 1, characterized in that, The specific method of S2.1 is as follows: The solid-phase potential and electrolyte potential of proton exchange membrane electrolysis in water are calculated based on the following equations: （1） （2） In the formula, δ s The solid-state conductivity is expressed in S / m. i The overpotential is V; R i As a local current source, A / m 3 ; δ m Proton conductivity, S / m, is determined by temperature and water content. λ The function, where λ Defined as the ratio of the number of water molecules to the number of charged nodes: （3） Equilibrium potential E eq (V) is defined by the Nernst equation as: （4） In the formula, n The number of electrons participating in the electrode reaction; F This is the Faraday constant, with a value of 96485 C / mol; R This is the universal gas constant; T To calculate the temperature at each point within the domain, the unit is... K ; C R and C O It is a dimensionless expression describing the concentration dependence of the oxidized and reduced substances in the reaction; The current density at the electrode and cathode in proton exchange membrane electrolysis of water is related to the local concentration of each substance participating in the reaction on the electrode surface, and is defined as: （5） In the formula, i 0 represents the exchange current density, with units of A / m. 2 ; α a and α c These are the charge transfer coefficients of the anode and cathode, respectively. α a + α c = n , η The activation overpotential is expressed in V.

4. The corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis to produce hydrogen according to claim 3, characterized in that, In the above formula (4), the reference equilibrium potential for each electrode reaction is... E eq,ref( T ), which can be determined by the standard free energy Δ H and reaction entropy Δ S The calculation shows that: （6）。 5. The corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis to produce hydrogen according to claim 3, characterized in that, The activation overpotential η Defined as: （7） Taking electron transfer into account, the electrochemical reaction equation is expressed as: （8） In the formula, ν i is the stoichiometric coefficient of the reactants.

6. The corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis to produce hydrogen according to claim 5, characterized in that, The specific method of S2.2 is as follows: The volume fraction of each component s i and stoichiometric coefficient ν i Introducing the equilibrium potential equation and the Butler-Volmer equation, using s i νi Indicate C i Substituting equations (4) and (5), we can obtain the following expression: （9） （10） （11） （12）。 7. The corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis to produce hydrogen according to claim 1, characterized in that, The PEMWE single-cell testing system in S3 uses a commercial CCM, specifically: IrO2 2.2 mg / cm³. 2 Pt / C 1.2 mg / cm 2 Nafion 115 has an active surface area of ​​6.25 cm². 2 The anode and cathode PTLs are made of titanium felt and Toray 060 carbon paper, respectively. The titanium felt is 250 μm thick and has a porosity of 65%, while the Toray 060 carbon paper is 192 μm thick and has a porosity of 78%. Both the cathode and anode are made of titanium plates with parallel flow channels. The flow channel plates are clamped by two stainless steel end plates and tightened by eight evenly distributed M6 bolts with a torque of 5 N·m. To prevent leakage, PTFE is used for interlayer sealing. The PEMWE single-cell testing system includes a DC power supply, a water tank, a peristaltic pump, an electrolytic cell, an electric heater, and connecting pipelines.

8. The corrected calculation method for electrochemical kinetics of proton exchange membrane water electrolysis to produce hydrogen according to claim 7, characterized in that, The specific method for the testing process in S3 is as follows: During the test, a DC power supply provides current to the electrolytic cell, and the power of the electric heater is adjusted by PID control to ensure a constant inlet water temperature in the electrolytic cell. Deionization is supplied to the anode of the electrolytic cell by a peristaltic pump at a flow rate of 15 mL / min. The deionization resistivity is >18.2 MΩ·cm. The generated H2 and O2 are discharged into the external environment through the connecting pipeline, and the carried outlet water is returned to the water tank through the separator to complete one cycle. To remove residual impurities introduced during the CCM manufacturing process, an electrolytic cell activation process is performed before each experimental test, and the entire activation process lasts for 12 hours. During the experiment, the electrolysis current density was changed by adjusting the DC power supply. Each data acquisition required the system to run stably for more than 180 seconds, and the current and voltage were recorded in the last 60 seconds. All tests were conducted under the conditions of an inlet water temperature of 65℃ and a back pressure of atmospheric pressure.

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