Quantitative Evaluation Method for the Influence of Hydrogen Permeation on the Polarization Voltage of Fuel Cells

Abstract

The present invention discloses a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell, belonging to the field of fuel cell process simulation. The method includes the following steps: respectively constructing a multi-physics field coupling model of a fuel cell without hydrogen permeation and with hydrogen permeation; obtaining the voltage-current curves and electrode reaction overpotentials of the fuel cell without hydrogen permeation and with hydrogen permeation based on the multi-physics field coupling models of the fuel cell without hydrogen permeation and with hydrogen permeation; calculating the ohmic polarization voltage loss caused by hydrogen permeation, the concentration polarization voltage loss caused by hydrogen permeation, and the activation polarization voltage loss caused by hydrogen permeation based on the voltage-current curves and electrode reaction overpotentials of the fuel cell without hydrogen permeation and with hydrogen permeation. The present invention can quantitatively evaluate the influence of hydrogen permeation on the three polarization voltages of a fuel cell, providing a more accurate theoretical basis for the design optimization, performance prediction, and fault diagnosis of fuel cells.

Description

Technical Field

[0001] The present invention belongs to the technical field of fuel cell process simulation, and particularly relates to a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell. Background Art

[0002] Fuel cells are widely regarded as an important development direction for future clean energy due to their significant advantages such as high efficiency, environmental protection, and low emissions. However, in practical applications, hydrogen permeation is one of the important factors affecting the performance of fuel cells. Hydrogen permeation not only causes a decrease in the electrical performance output of the battery but also has an adverse impact on the long-term stability and safety of the battery. Currently, although there are some models that can quantitatively calculate the amount of hydrogen permeation, the specific influence of hydrogen permeation on the three main polarization losses (concentration polarization, ohmic polarization, and activation polarization) of fuel cells has not been effectively analyzed. Therefore, the present invention proposes a new analysis method. Summary of the Invention

[0003] To solve the above technical problems, the present invention proposes a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell to solve the problems existing in the above prior art.

[0004] To achieve the above object, the present invention provides a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell, including:

[0005] Constructing a multi-physics field coupling model of a fuel cell without hydrogen permeation and with hydrogen permeation respectively;

[0006] Obtaining the voltage-current curve and the electrode reaction overpotential of the fuel cell without hydrogen permeation and with hydrogen permeation based on the multi-physics field coupling model of the fuel cell without hydrogen permeation and with hydrogen permeation;

[0007] Calculating the ohmic polarization voltage loss caused by hydrogen permeation, the concentration polarization voltage loss caused by hydrogen permeation, and the activation polarization voltage loss caused by hydrogen permeation based on the voltage-current curve and the electrode reaction overpotential of the fuel cell without hydrogen permeation and with hydrogen permeation.

[0008] Optionally, the multi-physics field coupling model of the fuel cell includes one-dimensional, two-dimensional, and three-dimensional multi-physics field coupling models.

[0009] Optionally, the voltage-current curve includes: a steady-state polarization curve and a transient voltage-current curve.

[0010] Optionally, the process of calculating the ohmic polarization voltage loss caused by hydrogen permeation includes: calculating the ohmic polarization voltage loss caused by hydrogen permeation based on the operating voltage of the fuel cell and the electrode reaction overpotential in the voltage-current curve;

[0011] Wherein, the calculation expression of the ohmic polarization voltage loss caused by hydrogen permeation is:

[0012]

[0013] Wherein, is the ohmic polarization overpotential caused by hydrogen permeation, V without is the operating voltage of the fuel cell without considering hydrogen permeation, V with is the operating voltage of the fuel cell considering hydrogen permeation, η over_without is the overpotential of the electrode reaction without considering hydrogen permeation, η over_with is the overpotential of the electrode reaction considering hydrogen permeation.

[0014] Optionally, the calculation expression of the concentration polarization voltage loss caused by hydrogen permeation is:

[0015]

[0016] Wherein, is the concentration polarization loss voltage caused by hydrogen permeation, R is the gas constant, T is the temperature, n is the number of charge transfers, F is the Faraday constant, C ccl_without is the average oxygen concentration of the cathode catalyst layer without considering hydrogen permeation, C ccl_with is the average oxygen concentration of the cathode catalyst layer considering hydrogen permeation.

[0017] Optionally, the process of calculating the activation polarization voltage loss caused by hydrogen permeation includes: obtaining the activation polarization voltage loss caused by hydrogen permeation based on the concentration polarization loss voltage and the overpotential of the electrode reaction;

[0018] Among them, the calculation expression of the activation polarization voltage loss caused by hydrogen permeation is:

[0019]

[0020] Wherein, is the activation polarization voltage loss of the fuel cell caused by hydrogen permeation.

[0021] The present invention also provides a computer terminal device, including:

[0022] One or more processors;

[0023] A memory, coupled to the processor, for storing one or more programs;

[0024] When the one or more programs are executed by the one or more processors, the one or more processors implement a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell.

[0025] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell is realized.

[0026] Compared with the prior art, the present invention has the following advantages and technical effects:

[0027] The present invention provides a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell. By constructing a multi-physical field coupling model of a fuel cell without hydrogen permeation and with hydrogen permeation, the working state of the fuel cell under different hydrogen permeation conditions can be accurately simulated. By comparing the voltage-current curves and the overpotentials of electrode reactions without hydrogen permeation and with hydrogen permeation, the ohmic polarization voltage loss, concentration polarization voltage loss, and activation polarization voltage loss caused by hydrogen permeation can be quantitatively calculated. This method can provide a scientific basis for the design and optimization of fuel cells, reduce the negative impact of hydrogen permeation on the battery performance, and improve the efficiency and reliability of fuel cells. By accurately evaluating the influence of hydrogen permeation, the selection of fuel cell materials and the structural design can be guided, thereby optimizing the battery performance and extending its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings forming a part of this application are used to provide a further understanding of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation to this application. In the drawings:

[0029] Figure 1 is a flowchart of a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell according to an embodiment of the present invention;

[0030] Figure 2 is a schematic diagram of a three-dimensional multi-physical field coupling model of a fuel cell according to an embodiment of the present invention;

[0031] Figure 3 is a steady-state polarization curve of voltage-current of a fuel cell without hydrogen permeation and with hydrogen permeation according to an embodiment of the present invention;

[0032] Figure 4 is a curve of the change of overpotential with current of a fuel cell without hydrogen permeation and with hydrogen permeation according to an embodiment of the present invention;

[0033] Figure 5 is a curve of the change of ohmic polarization voltage loss of a fuel cell caused by hydrogen permeation with current according to an embodiment of the present invention;

[0034] Figure 6 is a curve of the change of concentration polarization voltage loss of a fuel cell caused by hydrogen permeation with current according to an embodiment of the present invention;

[0035] Figure 7Curve of the activation polarization voltage loss caused by hydrogen permeation in the embodiment of the present invention varying with current. Detailed implementation manners

[0036] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0037] It should be noted that the steps shown in the flowchart of the drawings can be executed in a computer system such as a set of computer-executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0038] Embodiment 1

[0039] To solve the problems of the prior art, the object of the present invention is to overcome the deficiencies of the existing technologies, and provides a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell. Aiming at the defects of the existing simulation technologies, considering the three types of polarization loss mechanisms of the fuel cell, a multi-physics field coupling model of the fuel cell is constructed, and the three types of polarization voltage losses caused by hydrogen permeation during the operation of the PEMFC are calculated through the model results.

[0040] This embodiment can quantitatively evaluate the influence of hydrogen permeation on the three polarization voltages of the fuel cell, and calculate the three types of polarization potential losses of concentration polarization, ohmic polarization and activation polarization caused by hydrogen permeation. Through this method, a more accurate theoretical basis can be provided for the design optimization, performance prediction and fault diagnosis of the fuel cell, thereby promoting the further development and application of the fuel cell technology.

[0041] As Figure 1 shown, this embodiment provides a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell, including: respectively constructing a multi-physics field coupling model of the fuel cell without hydrogen permeation and with hydrogen permeation; obtaining the voltage-current curves and the over-potential of the electrode reaction of the fuel cell without hydrogen permeation and with hydrogen permeation based on the multi-physics field coupling model of the fuel cell without hydrogen permeation and with hydrogen permeation; calculating the ohmic polarization voltage loss caused by hydrogen permeation, the concentration polarization voltage loss caused by hydrogen permeation and the activation polarization voltage loss caused by hydrogen permeation based on the voltage-current curves and the over-potential of the electrode reaction of the fuel cell without hydrogen permeation and with hydrogen permeation.

[0042] The specific steps are as follows:

[0043] S1: Respectively construct a multi-physics field coupling model of the fuel cell without hydrogen permeation and with hydrogen permeation;

[0044] S2: Obtain the voltage-current curves of the fuel cell without hydrogen permeation and with hydrogen permeation based on the model;

[0045] S3: Obtain the overpotentials of the electrode reactions of the fuel cell without hydrogen permeation and with hydrogen permeation based on the model;

[0046] S4: Calculate the ohmic polarization losses of the fuel cell without hydrogen permeation and with hydrogen permeation based on the model data, and obtain the ohmic polarization voltage loss caused by hydrogen permeation by taking the difference between the two.

[0047] S5: Calculate the concentration polarization losses of the fuel cell without hydrogen permeation and with hydrogen permeation based on the model data, and obtain the concentration polarization voltage loss caused by hydrogen permeation by taking the difference between the two.

[0048] S6: Calculate the activation polarization losses of the fuel cell without hydrogen permeation and with hydrogen permeation based on the model data, and obtain the activation polarization voltage loss caused by hydrogen permeation by taking the difference between the two.

[0049] Further, in the step S1, the multi-physics coupled fuel cell model includes one-dimensional, two-dimensional, and three-dimensional multi-physics coupled fuel cell models. The fuel cell functional layer includes a proton exchange membrane, a catalyst layer, a microporous layer, a diffusion base layer, a plate, and a flow channel. The multi-physics fields include an electric field, a temperature field, a gas-liquid two-phase flow velocity field, a gas-liquid two-phase flow pressure field, a gas component concentration field, and a membrane water concentration field. The multi-physics coupled model includes steady-state and transient processes.

[0050] Further, in the step S1, when there is hydrogen permeation, the multi-physics coupled model of the fuel cell should also consider the changes in the concentration field, electric field, temperature field, velocity field, and pressure field caused by the transfer of hydrogen in the membrane.

[0051] Further, in the step S1, when there is hydrogen permeation, the multi-physics coupled model of the fuel cell includes a hydrogen permeation sub-model, which includes the processes of hydrogen adsorption / desorption at the Ionomer interface in the pores of the catalyst layer, the transfer of dissolved hydrogen in the Ionomer and the proton exchange membrane, and the chemical or electrochemical reaction of hydrogen reaching the cathode catalyst layer with oxygen to form water. The mechanism of the transfer process of dissolved hydrogen in the Ionomer and the proton exchange membrane includes concentration diffusion, macroscopic convection, and electro-drag.

[0052] Further, in the step S1, the multi-physics coupled model of the fuel cell is solved by software such as Fluent and COMSOL, and the numerical solution methods include finite element, finite volume, and finite difference.

[0053] Further, in the step S1, the load of the multi-physics coupled model of the fuel cell includes steady-state current, transient current, steady-state voltage, or transient voltage.

[0054] Further, in the step S2, the voltage and current curves include steady-state polarization curves and transient voltage-current curves.

[0055] Further, in the step S3, the electrode reaction includes anodic hydrogen oxidation reaction and cathodic oxygen reduction reaction, and the electrode reaction overpotential includes activation polarization overpotential and concentration polarization overpotential.

[0056] Further, in the step S4, the ohmic polarization loss includes electron transfer loss and proton transfer loss.

[0057] Further, in the step S4, the ohmic polarization loss caused by hydrogen permeation is calculated by the following formula:

[0058]

[0059] where, is the ohmic polarization overpotential caused by hydrogen permeation, V without is the fuel cell operating voltage without considering hydrogen permeation obtained based on step S2, V with is the fuel cell operating voltage considering hydrogen permeation obtained based on step S2, η over_without is the electrode reaction overpotential without considering hydrogen permeation obtained based on step S3, η over_with is the electrode reaction overpotential considering hydrogen permeation obtained based on step S3.

[0060] Further, in the step S5, the concentration polarization loss includes voltage losses caused by the transfer of anodic hydrogen and cathodic oxygen.

[0061] Further, in the step S5, the formula for calculating the concentration polarization voltage loss of the fuel cell caused by hydrogen permeation is as follows:

[0062]

[0063] In the formula, is the concentration polarization loss voltage caused by hydrogen permeation, R is the gas constant, T is the temperature, n is the number of charge transfers, F is the Faraday constant, C ccl_without is the average oxygen concentration of the cathode catalyst layer without considering hydrogen permeation obtained based on step S5, C ccl_with is the average oxygen concentration of the cathode catalyst layer considering hydrogen permeation obtained based on step S5.

[0064] Further, the formula for calculating the activation polarization loss of the fuel cell caused by hydrogen permeation in the step S6 is as follows:

[0065]

[0066] where, is the activation polarization voltage loss of the fuel cell, η over_without is the electrode reaction overpotential without considering hydrogen permeation obtained based on step S3, η over_with is the electrode reaction overpotential considering hydrogen permeation obtained based on step S3, Cccl_without The average oxygen concentration, C, of the cathode catalyst layer without considering hydrogen permeation obtained based on step S5 ccl_with is the average oxygen concentration of the cathode catalyst layer considering hydrogen permeation obtained based on step S5.

[0067] Example 2

[0068] In this example, a quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell is provided, including the following steps:

[0069] 1) Construct a multi-physics coupling model of a fuel cell without hydrogen permeation and with hydrogen permeation respectively;

[0070] 2) Obtain the voltage-current curves of the fuel cell without hydrogen permeation and with hydrogen permeation based on the model;

[0071] 3) Obtain the overpotential of the electrode reaction of the fuel cell without hydrogen permeation and with hydrogen permeation based on the model;

[0072] 4) Based on the model data, calculate the ohmic polarization losses of the fuel cell without hydrogen permeation and with hydrogen permeation, and obtain the ohmic polarization voltage loss caused by hydrogen permeation by taking the difference between the two.

[0073] 5) Based on the model data, calculate the concentration polarization losses of the fuel cell without hydrogen permeation and with hydrogen permeation, and obtain the concentration polarization voltage loss caused by hydrogen permeation by taking the difference between the two.

[0074] 6) Calculate the activation polarization losses of the fuel cell without hydrogen permeation and with hydrogen permeation, and obtain the concentration polarization voltage loss caused by hydrogen permeation by taking the difference between the two.

[0075] The multi-physics coupling model of the fuel cell in step 1) above is a three-dimensional steady-state multi-physics coupling model.

[0076] The three-dimensional structure of the multi-physics coupling model of the fuel cell in step 1) above includes a proton exchange membrane, a catalyst layer, a microporous layer, a diffusion base layer, a plate and a flow channel, as Figure 2 shown.

[0077] The multi-physics coupling model of the fuel cell in step 1) above includes an electric field, a temperature field, a two-phase flow velocity field, a two-phase flow pressure field, a gas component concentration field and a membrane water concentration field.

[0078] The sub-process with hydrogen permeation in step 1) above includes the adsorption / desorption of hydrogen in the pores of the catalyst layer at the Ionomer interface, the transfer of dissolved hydrogen in the Ionomer and the proton exchange membrane, and the chemical or electrochemical reaction of the hydrogen reaching the cathode with oxygen to form water.

[0079] The mechanism of the transfer process of dissolved hydrogen in the Ionomer and the proton exchange membrane in step 1) above includes concentration diffusion, convection and electro-drag.

[0080] In the above step 1), the hydrogen permeation process is a steady-state process.

[0081] In the above step 1), the multi-physical field coupling model is solved based on the COMSOL finite element method.

[0082] In the above step 1), the load current range of the fuel cell in steady-state operation is 10 - 1810 mA / cm². -2 .

[0083] In the above step 2), it is a steady-state polarization curve. The voltage-current curve without hydrogen permeation is (V without -I), and the voltage-current curve with hydrogen permeation is (V with -I), as Figure 3 shown.

[0084] In the above step 3), the fuel cell electrode reactions include anodic hydrogen oxidation and cathodic oxygen reduction reactions. The sum of the overpotentials caused by the two reactions without hydrogen permeation is η over_without , and with hydrogen permeation is η over_with , as Figure 4 shown.

[0085] In the above step 4), the ohmic polarization loss includes the loss of electrons overcoming resistance during transmission and the loss of protons overcoming resistance during transmission.

[0086] In the above step 4), the ohmic polarization loss of the fuel cell without hydrogen permeation is η ohm_without , and with hydrogen permeation is η ohm_with . The calculation formulas are as follows:

[0087] η ohm_without = E eq - V without - η over_without (4)

[0088] η ohm_with = E eq - V with - η over_with (5)

[0089] Among them, E eq is the fuel cell equilibrium potential.

[0090] In the above step 4), the ohmic polarization voltage losses of the fuel cell without hydrogen permeation (η ohm_without ) and with hydrogen permeation (η ohm_with ), as well as the ohmic polarization voltage loss caused by hydrogen permeation:

[0091]

[0092] The calculation results are as Figure 5 shown.

[0093] The concentration polarization loss in the above step 5) is the voltage loss caused by the oxygen transfer at the cathode.

[0094] The calculation formula for the concentration polarization loss of the fuel cell in the above step 5) is as follows:

[0095]

[0096] Among them, η con is the voltage of the concentration polarization loss, R is the gas constant, T is the temperature, n is the number of charge transfers, F is the Faraday constant, C inlet is the inlet concentration of oxygen in the flow channel, and C ccl is the average oxygen concentration in the cathode catalyst layer.

[0097] The concentration polarization losses of the fuel cell without hydrogen permeation (η con_without ) and with hydrogen permeation (η con_with ) in the above step 5), and the concentration polarization voltage loss caused by hydrogen permeation:

[0098]

[0099] The calculation results are as Figure 6 shown.

[0100] The calculation formula for the activation polarization loss of the fuel cell in the above step 6) is as follows:

[0101] η act = η over - η con (9)

[0102] Among them, η act is the activation polarization voltage loss of the fuel cell, η over is the overpotential of the electrode reaction calculated in step 3), and η con is the concentration polarization voltage loss calculated in step 5).

[0103] The activation polarization losses of the fuel cell without hydrogen permeation (η act_without ) and with hydrogen permeation (η act_with ) in the above step 6), and the activation polarization voltage loss caused by hydrogen permeation:

[0104]

[0105] The calculation results are as Figure 7 shown.

[0106] Example 3

[0107] This example also provides a computer terminal device, including:

[0108] One or more processors;

[0109] A memory, coupled to the processor, for storing one or more programs;

[0110] When the one or more programs are executed by the one or more processors, the one or more processors implement a method for quantitatively evaluating the influence of hydrogen permeation on the polarization voltage of a fuel cell.

[0111] This embodiment also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, a method for quantitatively evaluating the influence of hydrogen permeation on the polarization voltage of a fuel cell is implemented.

[0112] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell, characterized in that It includes the following steps: Construct a fuel cell multi - physical - field coupling model without hydrogen permeation and a fuel cell multi - physical - field coupling model with hydrogen permeation respectively; Based on the fuel cell multi - physical - field coupling model without hydrogen permeation and the fuel cell multi - physical - field coupling model with hydrogen permeation, obtain the voltage - current curves and electrode reaction overpotentials of the fuel cell without hydrogen permeation and with hydrogen permeation; Based on the voltage - current curves and electrode reaction overpotentials of the fuel cell without hydrogen permeation and with hydrogen permeation, calculate the ohmic polarization voltage loss caused by hydrogen permeation, the concentration polarization voltage loss caused by hydrogen permeation, and the activation polarization voltage loss caused by hydrogen permeation; Based on the operating voltage of the fuel cell and the electrode reaction overpotential in the voltage - current curve, calculate the ohmic polarization voltage loss caused by hydrogen permeation; wherein, the calculation expression of the ohmic polarization voltage loss caused by hydrogen permeation is: In the formula, is the ohmic polarization overpotential caused by hydrogen permeation, is the working voltage of the fuel cell without considering hydrogen permeation, is the working voltage of the fuel cell considering hydrogen permeation, is the overpotential of the electrode reaction without considering hydrogen permeation, is the overpotential of the electrode reaction considering hydrogen permeation; The calculation expression of the concentration polarization voltage loss caused by hydrogen permeation is: In the formula, is the voltage loss due to concentration polarization caused by hydrogen permeation, R is the gas constant, T is the temperature, is the number of charge transfers, is the Faraday constant, is the average oxygen concentration in the cathode catalyst layer without considering hydrogen permeation, is the average oxygen concentration in the cathode catalyst layer considering hydrogen permeation; The process of calculating the activation polarization voltage loss caused by hydrogen permeation includes: obtaining the activation polarization voltage loss caused by hydrogen permeation based on the concentration polarization loss voltage and the electrode reaction overpotential; wherein, the calculation expression of the activation polarization voltage loss caused by hydrogen permeation is: In the formula, is the activation polarization voltage loss of the fuel cell caused by hydrogen permeation.

2. The method according to claim 1, wherein The fuel cell multi - physical - field coupling model includes one - dimensional, two - dimensional, and three - dimensional multi - physical - field coupling models.

3. The method according to claim 1, wherein The voltage - current curves include: steady - state polarization curves and transient voltage - current curves.

4. A computer terminal device, characterized in that, It includes: One or more processors; A memory, coupled to the processor, for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell as described in any one of claims 1 - 3.

5. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the quantitative evaluation method for the influence of hydrogen permeation on the polarization voltage of a fuel cell as described in any one of claims 1 - 3.

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