A cross-leakage estimation method, system, fuel cell, vehicle, medium and equipment

Abstract

The present invention relates to the field of fuel cell technology, and specifically to a crosstalk estimation method, system, fuel cell, vehicle, medium and equipment. The present invention uses the crosstalk estimation method so that the fuel cell system does not require additional detection equipment, and only requires the fuel cell system's own single-chip voltage acquisition system and temperature and current acquisition sensors to measure and calculate the crosstalk amount; it can realize real-time online crosstalk monitoring and calculation under the fuel cell operation state, and accurately reflect the crosstalk amount under the actual operation of the membrane electrode; the detection steps are simple and time-saving, and the deviation between the membrane electrode crosstalk detection measurement value and the actual membrane electrode crosstalk value during fuel cell operation is small.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a cross-leakage estimation method, system, fuel cell, vehicle, medium and equipment. Background Art

[0002] Proton exchange membrane fuel cells (PEMFCs) have been widely developed and applied as a clean, efficient, and green energy source. To achieve comparable reliability and longevity to traditional fuel vehicles, PEMFC systems are currently required to have a service life of at least 5,000 hours in passenger cars and at least 20,000 hours in commercial vehicles. These requirements pose significant challenges to the durability of PEMFCs.

[0003] As a core component of proton exchange membrane fuel cells (PEMFCs), the lifespan of the membrane electrode assembly (MEA) is crucial to the durability of PEMFCs. Different operating conditions during fuel cell operation can cause physical and chemical degradation of the PEM, leading to a gradual increase in crosstalk between the hydrogen and air chambers of the PEM. Therefore, online, real-time monitoring of the PEM crosstalk during fuel cell operation and calculating the actual crosstalk is crucial for ensuring the reliability and lifespan of PEMFCs. The PEM is a polymer electrolyte membrane that uses protons as the conductive charge. The MEA is an assembly composed of an electrolyte membrane and gas diffusion electrodes placed on either side, or a catalyst-coated membrane and gas diffusion layers placed on either side, assembled through a specific process. It is often referred to simply as the membrane electrode. Crosstalk is the process by which hydrogen migrates from the anode to the cathode through the PEM.

[0004] Prior art, such as CN111106370A, discloses a method for detecting membrane electrode cross-leakage in a fuel cell stack. The method comprises the following steps: Step 1: Perform a balance test on the fuel cell; Step 2: Introduce hydrogen and air into the anode and cathode of the balanced fuel cell, respectively; Step 3: Cut off the cathode air supply, start a timer, and record the stack voltage Ea1 of each cell at time t4; Step 4: After the cell voltage drops to 0.2V, cut off the anode hydrogen supply; Step 5: Cycle the fuel cell to the next life stage and repeat Steps 1-4 to obtain the cell voltage Ex1 of the fuel cell stack, where x = a, b, ... N; Step 6: Calculate the voltage change at different stack life cycle stages to determine the amount of cross-leakage. This method offers advantages such as more comparable test results and more accurate conclusions. However, its disadvantages include: 1. The membrane electrode cross-leakage detection process is cumbersome and time-consuming; 2. The membrane electrode cross-leakage detection cannot provide real-time online measurement of the fuel cell operating status; and 3. The measured value of the membrane electrode cross-leakage detection deviates significantly from the actual membrane electrode cross-leakage value during fuel cell operation. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a leakage estimation method, system, fuel cell, vehicle, medium and equipment that improve the deficiencies of the existing technology, realize the monitoring of the leakage status of the proton exchange membrane, the core material of the fuel cell, and the online calculation of the leakage amount, thereby improving the reliability and durability of the fuel cell.

[0006] In order to solve the above technical problems, the first technical solution adopted by the present invention is:

[0007] A crosstalk estimation method comprising:

[0008] The hydrogen leakage rate Q of the membrane electrode corresponding to the target cell n is calculated based on the stack current I, fuel cell temperature T, the difference △E between the average cell voltage Eave and the voltage En of the target cell n during the operation of the fuel cell:

[0009]

[0010] Where F is the Faraday constant and R is the gas constant.

[0011] Preferably, the target single chip n is one of the single chips whose voltage drops by more than a threshold value after the supply of hydrogen and / or air t to the fuel cell stack is stopped during the fuel cell shutdown process.

[0012] Preferably, the t is 1-5s.

[0013] In order to solve the above technical problems, the second technical solution adopted by the present invention is:

[0014] A cross-link estimation system comprising:

[0015] Current acquisition device, to obtain the stack current I during the operation of the fuel cell;

[0016] A temperature acquisition device for acquiring the fuel cell temperature T during fuel cell operation;

[0017] A single-chip voltage acquisition device is used to obtain the average single-chip voltage Eave of the stack and the voltage En of the target single-chip n; and

[0018] The processor calculates the hydrogen leakage rate Q of the membrane electrode corresponding to the target cell n based on the stack current I, the fuel cell temperature T, the difference △E between the average cell voltage Eave of the stack and the voltage En of the target cell n:

[0019]

[0020] Where F is the Faraday constant and R is the gas constant.

[0021] Preferably, the target single chip n is one of the single chips whose voltage drops by more than a threshold value after the supply of hydrogen and / or air t to the fuel cell stack is stopped during the fuel cell shutdown process.

[0022] Preferably, the t is 1-5s.

[0023] In order to solve the above technical problems, the third technical solution adopted by the present invention is:

[0024] A fuel cell comprises the above-mentioned cross-leakage estimation system.

[0025] In order to solve the above technical problems, the fourth technical solution adopted by the present invention is:

[0026] A vehicle comprises the above-mentioned fuel cell.

[0027] In order to solve the above technical problems, the fifth technical solution adopted by the present invention is:

[0028] A medium stores a computer program, which implements the crosstalk estimation method as described above when executed by a processor.

[0029] In order to solve the above technical problems, the sixth technical solution adopted by the present invention is:

[0030] A computing device comprises: a processor and a memory, wherein the processor is used to run a program stored in the memory, wherein the program executes the crosstalk estimation method according to any one of claims 1 to 3 when running.

[0031] The beneficial effects of the present invention are: through the cross-leakage estimation method, the fuel cell system does not need additional detection equipment, and only the fuel cell system's own single-chip voltage acquisition system and temperature and current acquisition sensors are required to measure and calculate the cross-leakage amount; real-time online cross-leakage amount monitoring and calculation under the fuel cell operation state can be realized, accurately reflecting the cross-leakage amount under the actual operation of the membrane electrode; the detection steps are simple and time-saving, and the deviation between the membrane electrode cross-leakage detection measurement value and the actual cross-leakage value of the membrane electrode when the fuel cell is running is small. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic structural diagram of a fuel cell according to a specific embodiment of the present invention;

[0033] Explanation of reference numerals: 1. fuel cell; 2. single-chip voltage acquisition device; 3. temperature acquisition device; 4. current acquisition device; DETAILED DESCRIPTION

[0034] To illustrate the technical content, achieved objectives and effects of the present invention in detail, the following description is given in conjunction with the embodiments and accompanying drawings.

[0035] Example 1

[0036] A fuel cell membrane electrode cross-leakage estimation method, comprising:

[0037] The hydrogen leakage rate Q of the membrane electrode corresponding to the target cell n is calculated based on the stack current I, fuel cell temperature T, the difference △E between the average cell voltage Eave and the voltage En of the target cell n during the operation of the fuel cell:

[0038]

[0039] Where F is the Faraday constant and R is the gas constant;

[0040] The target single chip n is one of the single chips whose voltage drops by more than a threshold value 1 second after the supply of hydrogen and / or air to the fuel cell stack is stopped during the shutdown process of the fuel cell.

[0041] The above equation is derived from a simplified mathematical expression of the fuel cell polarization curve. 22.4 represents the molar volume of the gas under standard conditions, 60 represents 60 seconds (because the time unit for calculating the leakage rate is minutes, it is multiplied by 60s), the Faraday constant F is 96485, the gas constant R is 8.314, 2 represents the number of electrons involved in the reaction of each hydrogen molecule, and e represents a natural constant. Because this equation is derived from a mathematical expression that characterizes the reaction principle of the fuel cell polarization curve, it is universal and applicable, and is not limited to a certain fuel cell engine; after substituting the constants, Q is:

[0042]

[0043] Substituting into data set 1, the fuel cell current is 50A, the fuel cell temperature is 333K, the average fuel cell voltage per cell is 0.8V, the voltage corresponding to cell n is 0.7V, and the voltage difference between cell n and the average cell is 0.1V. After calculation, the hydrogen leakage rate Q corresponding to cell n is 2.95 standard liters per minute.

[0044] Substituting into data set 2, the fuel cell current is 120A, the fuel cell temperature is 340K, the average fuel cell voltage per cell is 0.745V, the voltage corresponding to cell n is 0.7V, and the voltage difference between cell n and the average cell is 0.045V. It is calculated that the hydrogen leakage rate corresponding to cell n is 2.65 standard liters per minute.

[0045] Substituting into data set three, the fuel cell current is 150A, the fuel cell temperature is 340K, the average fuel cell voltage per cell is 0.735V, the voltage corresponding to cell n is 0.695V, and the voltage difference between cell n and the average cell is 0.04V. It is calculated that the hydrogen leakage rate corresponding to cell n is 1.04 standard liters per minute.

[0046] Example 2

[0047] A cross-link estimation system comprising:

[0048] The current acquisition device 4 is used to obtain the stack current I during the operation of the fuel cell 1;

[0049] The temperature acquisition device 3 is used to obtain the fuel cell temperature T during the operation of the fuel cell 1;

[0050] The single-chip voltage acquisition device 2 obtains the average single-chip voltage Eave of the stack and the voltage En of the target single-chip n; and

[0051] The processor calculates the hydrogen leakage rate Q of the membrane electrode corresponding to the target cell n based on the stack current I, the fuel cell temperature T, the difference △E between the average cell voltage Eave of the stack and the voltage En of the target cell n:

[0052]

[0053] Where F is the Faraday constant and R is the gas constant.

[0054] The target single chip n is one of the single chips whose voltage drops by more than a threshold value 3 seconds after the supply of hydrogen and / or air to the fuel cell stack is stopped during the shutdown process of the fuel cell.

[0055] Example 3

[0056] A fuel cell includes the cross-talk estimation system described in the second embodiment.

[0057] Example 4

[0058] A vehicle comprises the fuel cell described in embodiment three.

[0059] Example 5

[0060] A medium stores a computer program, which, when executed by a processor, implements the crosstalk estimation method as described in the first embodiment.

[0061] Example 6

[0062] A computing device includes: a processor and a memory, wherein the processor is configured to run a program stored in the memory, wherein the program executes the crosstalk estimation method described in the first embodiment when running.

[0063] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's description and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A crosstalk estimation method, characterized in that: include The hydrogen leakage rate Q of the membrane electrode corresponding to the target cell n is calculated based on the stack current I, fuel cell temperature T, the difference △E between the average cell voltage Eave and the voltage En of the target cell n during the operation of the fuel cell: ； Where F is the Faraday constant and R is the gas constant; The target single chip n is one of the single chips whose voltage drops by more than a threshold value after the fuel cell stops supplying hydrogen and / or air to the stack during shutdown; The t is 1-5s.

2. A crosstalk estimation system, characterized in that: include Current acquisition device, to obtain the stack current I during the operation of the fuel cell; A temperature acquisition device for acquiring the fuel cell temperature T during fuel cell operation; The single-chip voltage acquisition device obtains the average single-chip voltage Eave of the stack and the voltage En of the target single-chip n; as well as The processor calculates the hydrogen leakage rate Q of the membrane electrode corresponding to the target cell n based on the stack current I, the fuel cell temperature T, the difference △E between the average cell voltage Eave of the stack and the voltage En of the target cell n: ； Where F is the Faraday constant and R is the gas constant; The target single chip n is one of the single chips whose voltage drops by more than a threshold value after the fuel cell stops supplying hydrogen and / or air to the stack during shutdown; The t is 1-5s.

3. A fuel cell, characterized in that: The invention comprises the crosstalk estimation system according to claim 2.

4. A vehicle, characterized in that: Comprising the fuel cell according to claim 3.

5. A medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the crosstalk estimation method according to claim 1 is implemented.

6. A computing device, characterized in that include: A processor and a memory, wherein the processor is used to run a program stored in the memory, wherein the crosstalk estimation method according to claim 1 is executed when the program is run.

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