Method for testing area specific resistance of fuel cell

Abstract

The embodiment of the invention discloses a fuel cell area specific resistance testing method, which comprises the following steps: sequentially stacking first carbon paper, a first polar plate, a first membrane electrode, a second polar plate and second carbon paper between a first pressure head and a second pressure head, and applying first pressure and first voltage to two ends of the first pressure head and the second pressure head to obtain a first resistance value R1; replacing the first membrane electrode with a second membrane electrode to obtain a second resistance value R2; obtaining a resistance value difference based on the first resistance value R1 and the second resistance value R2; acquiring the area of the parts of the residual membrane electrode respectively attached to the first polar plate and the second polar plate at the same time to obtain the residual contact area; and obtaining the area specific resistance between the first polar plate and the residual membrane electrode and between the second polar plate and the residual membrane electrode based on the resistance value difference and the residual contact area. According to the invention, the problems of the resistance between the carbon paper and the bipolar plate and the resistance of the bipolar plate and the membrane electrode during the test of the area specific resistance of the fuel cell are solved, and the test precision of the area specific resistance of the fuel cell is improved.

Description

Technical Field

[0001] The invention relates to the technical field of fuel cells, and in particular to a method for testing area specific resistance of a fuel cell. Background Art

[0002] Area specific resistance is an important factor causing poor fuel cell performance and an important indicator for fuel cell fault diagnosis. The surface treatment of the bipolar plate (BP), the surface state of the membrane electrode (GDL), and the assembly process will cause the area specific resistance to increase. Excessive local area specific resistance will cause the local current density to increase, and excessive local temperature will cause hot spots in the membrane electrode, resulting in a decrease in performance and durability. In an assembled fuel cell, most of the area specific resistance comes from the area between the plate flow field and the membrane electrode.

[0003] At present, the commonly used test method for the area specific resistance between the bipolar plate and the membrane electrode is mainly divided into two steps:

[0004] Step 1: Place two standard carbon papers (e.g., 7*7 cm, selected according to the size of the fixture) between the upper and lower pressure heads of the fixture, clamp the two carbon papers according to a given pressure, apply voltage across the upper and lower pressure heads, and read the resistance value R1;

[0005] In step 2, the two sheets of carbon paper are still placed between the upper and lower pressure heads of the fixture, and the electrode plate, membrane electrode and electrode plate are placed between the two sheets of carbon paper in sequence. The components are clamped according to a given pressure, a voltage is applied across the upper and lower pressure heads, and the resistance value R2 is read.

[0006] At the end of the test process, the area specific resistance ASR between the plate and the membrane electrode is calculated according to the following formula BPP-MEA :

[0007] ASR BPP-MEA =(R2-R1)*S contact / 2

[0008] Among them, S contact is the contact area between the electrode plate and the membrane electrode;

[0009] The above test process includes the area specific resistance between the standard carbon paper and the electrode plate, the electrode plate resistance and the membrane electrode resistance, which affects the test accuracy of the area specific resistance between the bipolar plate and the membrane electrode. Summary of the invention

[0010] The present application provides a method for testing the area specific resistance of a fuel cell, so as to at least solve the problem of poor testing accuracy of the area specific resistance between the bipolar plate and the membrane electrode. The technical solution of the present application is as follows:

[0011] A method for testing the area specific resistance of a fuel cell, comprising:

[0012] The first carbon paper, the first electrode, the first membrane electrode, the second electrode plate and the second carbon paper are sequentially stacked between the first pressure head and the second pressure head at both ends of the fixture, and a first pressure and a first voltage are applied to both ends of the first pressure head and the second pressure head to obtain a first resistance value R1;

[0013] The first carbon paper, the first electrode, the second membrane electrode, the second electrode plate and the second carbon paper are sequentially stacked between the first pressure head and the second pressure head at both ends of the clamp, and a second pressure and a second voltage are applied at both ends of the first pressure head and the second pressure head to obtain a second resistance value R2; the area of ​​the second membrane electrode is smaller than the area of ​​the first membrane electrode;

[0014] Obtaining a remaining membrane electrode, wherein the remaining membrane electrode is the remaining portion of the membrane electrode after removing the portion of the first membrane electrode corresponding to the portion overlapping with the second membrane electrode;

[0015] Obtaining the areas of the remaining membrane electrode portions that are in contact with the first electrode plate and the second electrode plate, respectively, to obtain a remaining contact area;

[0016] Obtaining a resistance value difference based on the first resistance value R1 and the second resistance value R2;

[0017] The area specific resistance ASR between the first electrode plate, the second electrode plate and the remaining membrane electrode is obtained based on the resistance value difference and the remaining contact area. ohmic .

[0018] In some specific implementations, the first resistance value R1 includes:

[0019] R1=R PRESS1-GDL1 +R GDL1 +R GDL1-PB1 +R PB1 +R PB1-MEA1 +R MEA1 +R PB2-MEA1 +R PB2 +R GDL2-PB2 +R GDL2 +R PRESS2-GDL2

[0020] Among them, R PRESS1-GDL1 is the resistance between the first pressure head and the first carbon paper, R GDL1 is the resistance of the first carbon paper, R GDL1-PB1 is the resistance between the first carbon paper and the first electrode plate, R PB1 is the resistance of the first plate, R PB1-MEA1 is the resistance between the first electrode plate and the first membrane electrode, R MEA1is the resistance of the first membrane electrode, R PB2-MEA1 is the resistance between the first membrane electrode and the second electrode plate, R PB2 is the resistance of the second plate, R GDL2-PB2 is the resistance between the second electrode plate and the second carbon paper, R GDL2 is the resistance of the second carbon paper, R PRESS2-GDL2 is the resistance between the second pressure head and the second carbon paper.

[0021] In some specific implementations, the second resistance value R2 includes:

[0022] R2=R PRESS1-GDL1 +R GDL1 +R GDL1-PB1 +R PB1 +R PB1-MEA2 +R MEA2 +R PB2-MEA2 +R PB2 +R GDL2-PB2 +R GDL2 +R PRESS2-GDL2

[0023] Among them, R PB1-MEA2 is the resistance between the first electrode plate and the second membrane electrode, R MEA2 is the resistance of the second membrane electrode, R PB2-MEA2 is the resistance between the second membrane electrode and the second electrode plate.

[0024] In some specific embodiments, the remaining contact area refers to the effective contact area between the remaining membrane electrode and the membrane electrode after removing the flow channel groove area of ​​the first electrode plate and the second electrode plate.

[0025] In some specific embodiments, the first pressing head and the second pressing head are made of metal copper, and gold is plated on the surface thereof.

[0026] In some specific embodiments, the first pressure head and the second pressure head have the same specifications.

[0027] In some specific implementations, the first pressure and the second pressure are between 1 KN and 20 KN, and the first pressure and the second pressure have the same pressure value.

[0028] In some specific implementations, the first voltage and the second voltage have the same voltage value.

[0029] In some specific embodiments, the first electrode plate and the second electrode plate have the same specifications.

[0030] In some specific embodiments, the first carbon paper and the second carbon paper have the same specifications.

[0031] By adopting the above technical solution, the method for testing the area specific resistance of a fuel cell provided in the present application has the following beneficial effects:

[0032] The embodiment of the present application discloses a method for testing the area specific resistance of a fuel cell. The testing method provided by the present application includes: stacking the first carbon paper, the first electrode, the first membrane electrode, the second electrode plate, and the second carbon paper in sequence between the first pressure head and the second pressure head at both ends of the clamp, and applying the first pressure and the first voltage at both ends of the first pressure head and the second pressure head to obtain the first resistance value R1; stacking the first carbon paper, the first electrode plate, the second membrane electrode, the second electrode plate, and the second carbon paper in sequence between the first pressure head and the second pressure head at both ends of the clamp, and applying the second pressure and the second voltage at both ends of the first pressure head and the second pressure head to obtain the second resistance value R2; the area of ​​the second membrane electrode is smaller than the area of ​​the first membrane electrode; obtaining the remaining membrane electrode, which is the remaining part of the membrane electrode after the first membrane electrode corresponding to the part overlapping with the second membrane electrode is removed; obtaining the area of ​​the remaining membrane electrode that is simultaneously bonded to the first electrode plate and the second electrode plate, respectively, to obtain the remaining contact area; obtaining the resistance value difference based on the first resistance value R1 and the second resistance value R2; obtaining the area specific resistance ASR between the first electrode plate, the second electrode plate and the remaining membrane electrode based on the resistance value difference and the remaining contact area ohmic The present application solves the problem of interference resistance including the resistance between carbon paper and bipolar plate, the resistance between bipolar plate and membrane electrode itself, etc. when testing the area specific resistance of fuel cell, thereby improving the test accuracy of the area specific resistance of fuel cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 Schematic diagram of a method for testing the area specific resistance of a fuel cell provided in an embodiment of the present application Figure 1 ;

[0035] Figure 2 Schematic diagram of a method for testing the area specific resistance of a fuel cell provided in an embodiment of the present application Figure 2 ;

[0036] Figure 3 Schematic diagram of the commonly used fuel cell area specific resistance test method Figure 1 ;

[0037] Figure 4 Schematic diagram of the commonly used fuel cell area specific resistance test method Figure 2 .

[0038] The following is a supplementary description of the attached drawings:

[0039] 101-first pressure head; 102-second pressure head;

[0040] 201-first carbon paper; 202-second carbon paper;

[0041] 301-first electrode plate; 302-second electrode plate;

[0042] 401 - first membrane electrode; 402 - second membrane electrode; 403 - third membrane electrode. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0044] For the following defined terms, these definitions shall apply unless a different definition is given in the claims or elsewhere in this specification. All numerical values, whether or not explicitly indicated, are defined herein as modified by the term "about". The term "about" generally refers to a numerical range that a person of ordinary skill in the art considers to be equivalent to the stated values ​​to produce substantially the same properties, functions, results, etc. A numerical range indicated by a lower value and a higher value is defined to include all numerical values ​​included in the numerical range and all subranges included in the numerical range.

[0045] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0047] Fuel cell area specific resistance ASR ohmic The essence of the resistance is the sum of the contraction resistance caused by the current passing through the contacting parts of the materials and the surface film resistance. The resistance of the fuel cell changes in proportion to the area, thus allowing fuel cells of different areas to be compared. Area specific resistance ASR ohmic The calculation method is to multiply the ohmic resistance of the fuel cell by the area: ASR ohmic =A fuel cell *R ohmic , unit is Ω*cm 2 ,In an assembled fuel cell, most of the area specific resistance comes from the area specific resistance between the bipolar plate and the membrane electrode.

[0048] See also Figure 3 and Figure 4 , Commonly used fuel cell area specific resistance test methods include:

[0049] The first carbon paper 201 and the second carbon paper 202 are stacked in sequence between the first pressure head 101 and the second pressure head 101 at both ends of the clamp, and a third pressure and a third voltage are applied at both ends of the first pressure head 101 and the second pressure head 102 to obtain a third resistance value R3; wherein the third resistance value R3 includes the resistance between the first pressure head 101 and the first carbon paper 201, the resistance of the first carbon paper 101, the resistance of the second carbon paper 102, and the resistance between the second pressure head 102 and the second carbon paper 202.

[0050] That is: R3=R PRESS1-GDL1 +R GDL1 +R GDL2 +R PRESS2-GDL2 ;

[0051] Among them, R PRESS1-GDL1 is the resistance between the first pressure head 101 and the first carbon paper 201, R GDL1 is the resistance of the first carbon paper 201, R GDL2 is the resistance of the second carbon paper 202, R PRESS2-GDL2 is the resistance between the second pressure head 102 and the second carbon paper 202 .

[0052] The first carbon paper 201, the first electrode 301, the third membrane electrode 403, the second electrode 302 and the second carbon paper 202 are sequentially stacked between the first pressure head 101 and the second pressure head 101 at both ends of the clamp, and a fourth pressure and a fourth voltage are applied at both ends of the first pressure head 101 and the second pressure head 102 to obtain a fourth resistance value R4; wherein the fourth resistance value R4 includes the resistance between the first pressure head 101 and the first carbon paper 201, the resistance of the first carbon paper 201, the resistance between the first carbon paper 201 and the first electrode 301, the resistance of the first electrode 301, the resistance between the first electrode 301 and the third membrane electrode 403, the resistance of the third membrane electrode 403, the resistance between the third membrane electrode 403 and the second electrode 302, the resistance of the second electrode 302, the resistance between the second electrode 302 and the second carbon paper 202, the resistance of the second carbon paper 202, and the resistance between the second pressure head 102 and the second carbon paper 202. That is: R4 = R PRESS1-GDL1 +R GDL1 +R GDL1-PB1 +R PB1 +R PB1-MEA3 +R MEA3 +R PB2-MEA3 +R PB2 +R GDL2-PB2 +R GDL2 +R PRESS2-GDL2

[0053] Among them, R PRESS1-GDL1 is the resistance between the first pressure head 101 and the first carbon paper 201, R GDL1 is the resistance of the first carbon paper 201, R GDL1-PB1 is the resistance between the first carbon paper 201 and the first electrode plate 301, R PB1 is the resistance of the first electrode 301, R PB1-MEA3 is the resistance between the first electrode plate 301 and the third membrane electrode 403, R MEA3 is the resistance of the third membrane electrode 403, R PB2-MEA3 is the resistance between the third membrane electrode 403 and the second electrode plate 302, R PB2 is the resistance of the second electrode 302, R GDL2-PB2 is the resistance between the second electrode plate 302 and the second carbon paper 202, R GDL2 is the resistance of the second carbon paper 202, R PRESS2-GDL2 is the resistance between the second pressure head 102 and the second carbon paper 202 .

[0054] Obtaining a resistance value difference based on the third resistance value R3 and the fourth resistance value R4;

[0055] Obtaining the contact area between the first electrode plate 301 and the second electrode plate 302 and the third membrane electrode 403;

[0056] The area specific resistance ASR between the first electrode plate 301 and the second electrode plate 302 and the third membrane electrode 403 is obtained based on the resistance value difference and the contact area. BPP-MEA3 , namely ASR BPP-MEA3 =(R4-R3)*S contact .

[0057] Among them, S contact is the contact area between the first electrode plate 301 and the second electrode plate 302 and the third membrane electrode 403 .

[0058] Specifically, the third pressure and the fourth pressure respectively applied at both ends of the first pressure head 101 and the second pressure head 102 have the same pressure value, the third voltage and the fourth voltage respectively applied at both ends of the first pressure head 101 and the second pressure head 102 have the same voltage value, the first carbon paper 201 and the second carbon paper 202 have the same specifications, wherein the specifications of the first carbon paper 201 and the second carbon paper 202 are selected according to the size of the fixture, and the areas of the opposite sides (referred to as opposite surfaces) of the first pressure head 101 and the second pressure head 102 are the same. The consistency of the test conditions is ensured, and the errors caused by differences in pressure, voltage or specifications are reduced, so that the test results are more accurate and reliable.

[0059] From the above test, it can be known that the resistance difference obtained by subtracting the third resistance value R3 from the fourth resistance value R4 includes not only the resistance between the first electrode plate 301 and the second electrode plate 302 and the third membrane electrode 403, but also the resistance between the first carbon paper 201 and the first electrode plate 301, the resistance between the second carbon paper 202 and the second electrode plate 302, the resistance of the first electrode plate 301, the resistance of the second electrode plate 302 and the resistance of the third membrane electrode 403. Therefore, the area specific resistance ASR between the first electrode plate 301 and the second electrode plate 302 and the third membrane electrode 403 obtained by the above test is BPP-MEA3 The interference resistance includes the resistance between the first carbon paper 201 and the first electrode 301, the resistance between the second carbon paper 202 and the second electrode 302, the resistance of the first electrode 301, the resistance of the second electrode 302 and the resistance of the third membrane electrode 403, which cannot be removed during this test, thus affecting the area specific resistance ASR between the first electrode 301 and the second electrode 302 and the third membrane electrode 403. BPP-MEA3 The test accuracy.

[0060] See also Figure 1 and Figure 2 , a fuel cell area specific resistance testing method provided in an embodiment of the present application includes:

[0061] The first carbon paper 201, the first electrode 301, the first membrane electrode 401, the second electrode 302 and the second carbon paper 202 are stacked in sequence between the first pressure head 101 and the second pressure head 102 at both ends of the clamp, and a first pressure and a first voltage are applied at both ends of the first pressure head 101 and the second pressure head 102 to obtain a first resistance value R1; wherein the first resistance value R1 includes the resistance between the first pressure head 101 and the first carbon paper 201, the resistance of the first carbon paper 201, the resistance between the first carbon paper 201 and the first electrode 301, the resistance of the first electrode 301, the resistance between the first electrode 301 and the first membrane electrode 401, the resistance of the first membrane electrode 401, the resistance between the first membrane electrode 401 and the second electrode 302, the resistance of the second electrode 302, the resistance between the second electrode 302 and the second carbon paper 202, the resistance of the second carbon paper 202 and the resistance between the second pressure head 102 and the second carbon paper 202.

[0062] The first carbon paper 201, the first electrode 301, the second membrane electrode 402, the second electrode 302 and the second carbon paper 202 are sequentially stacked between the first pressure head 101 and the second pressure head 102 at both ends of the fixture, and a second pressure and a second voltage are applied at both ends of the first pressure head 101 and the second pressure head 102 to obtain a second resistance value R2; the area of ​​the second membrane electrode 402 is smaller than the area of ​​the first membrane electrode 401; wherein the second resistance value R2 includes the area between the first pressure head 101 and the first carbon paper 201 resistance, the resistance of the first carbon paper 201, the resistance between the first carbon paper 201 and the first electrode plate 301, the resistance of the first electrode plate 301, the resistance between the first electrode plate 301 and the second membrane electrode 402, the resistance of the second membrane electrode 402, the resistance between the second membrane electrode 402 and the second electrode plate 302, the resistance of the second electrode plate 302, the resistance between the second electrode plate 302 and the second carbon paper 202, the resistance of the second carbon paper 202, and the resistance between the second pressure head 102 and the second carbon paper 202.

[0063] Obtaining a remaining membrane electrode, where the remaining membrane electrode is the remaining portion of the membrane electrode after removing the portion of the first membrane electrode 401 that overlaps with the second membrane electrode 402;

[0064] Obtaining the area of ​​the remaining membrane electrode that is in contact with the first electrode plate 301 and the second electrode plate 302, respectively, to obtain the remaining contact area;

[0065] The resistance difference is obtained based on the first resistance value R1 and the second resistance value R2; the resistance difference includes the resistance between the first electrode plate 301 and the remaining membrane electrode, the resistance between the second electrode plate 302 and the remaining membrane electrode, and the resistance of the remaining membrane electrode. Since the resistance of the remaining membrane electrode is very small, it can be ignored. Therefore, the resistance difference includes the resistance between the first electrode plate 301 and the second electrode plate 302 and the remaining membrane electrode.

[0066] The area specific resistance ASR between the first electrode plate 301, the second electrode plate 302 and the remaining membrane electrode is obtained based on the resistance value difference and the remaining contact area. ohmic The problem of interference resistance, such as the resistance between the carbon paper and the bipolar plate, the resistance between the bipolar plate and the membrane electrode itself, etc., when testing the area specific resistance of the fuel cell is solved, thereby improving the test accuracy of the area specific resistance of the fuel cell.

[0067] The present application introduces a second membrane electrode 402, and the area of ​​the second membrane electrode 402 is smaller than the area of ​​the first membrane electrode 401, or the area of ​​the second membrane electrode 402 is larger than the area of ​​the first membrane electrode 401, and the membrane electrode difference between the first membrane electrode 401 and the second membrane electrode 402 is calculated to obtain the remaining membrane electrode, and the resistance between the remaining membrane electrode and the first electrode plate 301 and the second electrode plate 302 is obtained by testing. During the test, the same terms between the first pressure head 101 and the second pressure head 102 can be offset, so as to obtain a more accurate area specific resistance between the first electrode plate 301 and the second electrode plate 302 and the remaining membrane electrode. The test method is simple and easy to operate, and the test fixture is a commonly used test equipment, so it does not increase the test cost.

[0068] In some specific implementations, the first resistance value R1 includes:

[0069] R1=R PRESS1-GDL1 +R GDL1 +R GDL1-PB1 +R PB1 +R PB1-MEA1 +R MEA1 +R PB2-MEA1 +R PB2 +R GDL2-PB2 +R GDL2 +R PRESS2-GDL2

[0070] Among them, R PRESS1-GDL1 is the resistance between the first pressure head 101 and the first carbon paper 201, R GDL1 is the resistance of the first carbon paper 201, R GDL1-PB1 is the resistance between the first carbon paper 201 and the first electrode plate 301, R PB1 is the resistance of the first electrode 301, R PB1-MEA1 is the resistance between the first electrode plate 301 and the first membrane electrode 401, R MEA1 is the resistance of the first membrane electrode 401, R PB2-MEA1 is the resistance between the first membrane electrode 401 and the second electrode plate 302, R PB2 is the resistance of the second electrode 302, R GDL2-PB2 is the resistance between the second electrode plate 302 and the second carbon paper 202, R GDL2 is the resistance of the second carbon paper 202, RPRESS2-GDL2 is the resistance between the second pressure head 102 and the second carbon paper 202 .

[0071] Specifically, a fixture, a test carbon paper and a material to be tested are prepared, wherein the material to be tested includes a first electrode plate 301, a second electrode plate 302 and a first membrane electrode 401, and the test fixture includes a first pressure head 101 and a second pressure head 102 arranged opposite to each other, and the first carbon paper 201 and the second carbon paper 202 are arranged on the facing surfaces of the first pressure head 101 and the second pressure head 102, and the first electrode plate 301, the first membrane electrode 401 and the second electrode plate 302 are arranged in sequence between the first carbon paper 201 and the second carbon paper 202, so that the first pressure head 101 and the second pressure head 102 are arranged opposite to each other. The head 101, the first carbon paper 201, the first electrode plate 301, the first membrane electrode 401, the second electrode plate 302, the second carbon paper 202 and the second pressure head 102 are in full contact with each other, and a first pressure is applied at both ends of the first pressure head 101 and the second pressure head 102 to ensure good electrical contact, so that the current can smoothly pass through the component to be tested, and the current transmission efficiency is improved. Applying a certain pressure can also reduce the air gap between the components to prevent the gap from causing arcs or electrical breakdown, affecting the safety and accuracy of the test. Under the first pressure, a first voltage is applied at both ends of the first pressure head 101 and the second pressure head 102, and the first resistance value R1 is directly read to obtain the resistance between the first pressure head 101 and the second pressure head 102.

[0072] In some specific implementations, the second resistance value R2 includes:

[0073] R2=R PRESS1-GDL1 +R GDL1 +R GDL1-PB1 +R PB1 +R PB1-MEA2 +R MEA2 +R PB2-MEA2 +R PB2 +R GDL2-PB2 +R GDL2 +R PRESS2-GDL2

[0074] Among them, R PB1-MEA2 is the resistance between the first electrode plate 301 and the second membrane electrode 402, R MEA2 is the resistance of the second membrane electrode, R PB2-MEA2 is the resistance between the second membrane electrode 402 and the second electrode plate 302 .

[0075] Preferably, after testing the first resistance value R1, the clamp is released, the first membrane electrode 401 is directly taken out, the second membrane electrode 402 is placed between the first electrode plate 301 and the second electrode plate 302, and the first pressure head 101 and the second pressure head 102 are clamped again, so that the first electrode plate 301, the second membrane electrode 402 and the second electrode plate 302 are fully in contact with each other. Keeping other conditions unchanged, only the membrane electrode is changed to ensure the comparability of the test results. In addition, only the membrane electrode needs to be replaced, and there is no need to reset the entire test device, which greatly shortens the test time and reduces the additional cost caused by resetting the test device.

[0076] In some specific embodiments, the remaining contact area refers to the effective contact area with the remaining membrane electrode after removing the flow channel groove area of ​​the first electrode plate 301 and the second electrode plate 302. Specifically, the first electrode plate 301 and the second electrode plate 302 are provided with flow channel grooves, which are used to evenly distribute the reaction gases (such as hydrogen and oxygen) to various parts of the battery to ensure that the reaction can proceed evenly, and discharge the water produced by the reaction through the flow channel grooves to avoid flooding and maintain battery performance. The presence of the flow channel grooves reduces the actual contact area between the electrode plate and the membrane electrode. Therefore, the present application tests the actual effective contact area between the remaining membrane electrode and the first electrode plate 301 and the second electrode plate 302 through three-dimensional digital simulation, removes the influence of the flow channel groove part, and thereby improves the test accuracy of the area specific resistance of the fuel cell.

[0077] In some specific embodiments, the material of the first press head 101 and the second press head 102 is copper metal, and the surface thereof is gold-plated. Since copper metal has good electrical conductivity and thermal conductivity, as well as good mechanical properties, the accuracy and reliability of the test can be ensured. At the same time, gold plating on the surface of the first press head 101 and the second press head 102 can provide good electrical conductivity, while increasing wear resistance and corrosion resistance. This avoids excessively high specific resistance of the internal area of ​​the fixture due to oxidation, thereby affecting the actual test of the contact material.

[0078] In some specific embodiments, the first pressure head 101 and the second pressure head 102 have the same specifications. Using pressure heads of the same specifications can ensure the consistency of test conditions and obtain accurate and repeatable test results. Pressure heads of the same specifications help reduce variables caused by pressure head differences, making test results more reliable; and can also ensure that the pressure applied during the test is consistent.

[0079] In some specific embodiments, the first pressure and the second pressure are between 1KN and 20KN, and the pressure values ​​of the first pressure and the second pressure are the same. The area specific resistance of the fuel cell decreases with the increase of pressure. Increasing the pressure within a certain range can significantly reduce the area specific resistance of the fuel cell. During the two tests, the pressure values ​​applied at both ends of the first pressure head 101 and the second pressure head 102 are the same to ensure the consistency of the test conditions, so that the test results of the area specific resistance of the fuel cell are comparable and repeatable; the pressure value is in the range of 1KN to 20KN, which can not only ensure good test performance of the area specific resistance of the fuel cell, but also avoid excessive mechanical stress or damage to the test material.

[0080] In some specific implementations, the first voltage and the second voltage have the same voltage value. In two tests, the first voltage and the second voltage have the same voltage value, which ensures the consistency, comparability and accuracy of the tests, and also simplifies the experimental design and circuit configuration.

[0081] In some specific implementations, the first electrode plate 301 and the second electrode plate 302 have the same specifications. Using the same specifications of the electrode plates can reduce the variables introduced by the different electrode plates, making the test results more accurate.

[0082] In some specific embodiments, the first carbon paper 201 and the second carbon paper 202 have the same specifications. In order to ensure the consistency and comparability of the test results, it is necessary to perform the test under the same conditions. Using carbon paper of the same specifications can ensure the consistency of the test conditions, thereby making the test results more accurate and reliable. The carbon paper is placed on both sides of the object to be tested as a support to improve the contact condition. Using carbon paper of the same specifications can ensure that the contact conditions on both sides are the same, reducing the error introduced by different specifications of carbon paper.

[0083] The embodiment of the present application discloses a method for testing the area specific resistance of a fuel cell. The testing method provided by the present application includes: stacking the first carbon paper, the first electrode, the first membrane electrode, the second electrode plate, and the second carbon paper in sequence between the first pressure head and the second pressure head at both ends of the clamp, and applying the first pressure and the first voltage at both ends of the first pressure head and the second pressure head to obtain the first resistance value R1; stacking the first carbon paper, the first electrode plate, the second membrane electrode, the second electrode plate, and the second carbon paper in sequence between the first pressure head and the second pressure head at both ends of the clamp, and applying the second pressure and the second voltage at both ends of the first pressure head and the second pressure head to obtain the second resistance value R2; the area of ​​the second membrane electrode is smaller than the area of ​​the first membrane electrode; obtaining the remaining membrane electrode, which is the remaining part of the membrane electrode after the first membrane electrode corresponding to the part overlapping with the second membrane electrode is removed; obtaining the area of ​​the remaining membrane electrode that is simultaneously bonded to the first electrode plate and the second electrode plate, respectively, to obtain the remaining contact area; obtaining the resistance value difference based on the first resistance value R1 and the second resistance value R2; obtaining the area specific resistance ASR between the first electrode plate, the second electrode plate and the remaining membrane electrode based on the resistance value difference and the remaining contact area ohmic The present application solves the problem of interference resistance including the resistance between carbon paper and bipolar plate, the resistance between bipolar plate and membrane electrode itself, etc. when testing the area specific resistance of fuel cell, thereby improving the test accuracy of the area specific resistance of fuel cell.

[0084] The above description is only an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for testing the area specific resistance of a fuel cell, characterized in that: include: A first carbon paper (201), a first electrode plate (301), a first membrane electrode (401), a second electrode plate (302) and a second carbon paper (202) are sequentially stacked between a first pressure head (101) and a second pressure head (102) at both ends of the clamp, and a first pressure and a first voltage are applied to both ends of the first pressure head (101) and the second pressure head (102) to obtain a first resistance value R1; The first carbon paper (201), the first electrode (301), the second membrane electrode (402), the second electrode plate (302) and the second carbon paper (202) are sequentially stacked between the first pressure head (101) and the second pressure head (102) at both ends of the clamp, and a second pressure and a second voltage are applied to both ends of the first pressure head (101) and the second pressure head (102) to obtain a second resistance value R2; the area of ​​the second membrane electrode (402) is smaller than the area of ​​the first membrane electrode (401); Obtaining a remaining membrane electrode, wherein the remaining membrane electrode is the remaining portion of the first membrane electrode (401) after removing the portion overlapping with the second membrane electrode (402); Obtaining the areas of the remaining membrane electrode portions that are in contact with the first electrode plate (301) and the second electrode plate (302) respectively, to obtain a remaining contact area; Obtaining a resistance value difference based on the first resistance value R1 and the second resistance value R2; Based on the resistance value difference and the remaining contact area, an area specific resistance ASR between the first electrode plate (301) and the second electrode plate (302) and the remaining membrane electrode is obtained. ohmic .

2. A method for testing area specific resistance of a fuel cell according to claim 1, characterized in that: The first resistance value R1 includes: R1=R PRESS1-GDL1 +R GDL1 +R GDL1-PB1 +R PB1 +R PB1-MEA1 +R MEA1 +R PB2-MEA1 +R PB2 +R GDL2-PB2 +R GDL2 +R PRESS2-GDL2 Among them, R PRESS1-GDL1 is the resistance between the first pressure head (101) and the first carbon paper (201), R GDL1 is the resistance of the first carbon paper (201), R GDL1-PB1 is the resistance between the first carbon paper (201) and the first electrode plate (301), R PB1 is the resistance of the first electrode plate (301), R PB1-MEA1 is the resistance between the first electrode plate (301) and the first membrane electrode (401), R MEA1 is the resistance of the first membrane electrode (401), R PB2-MEA1 is the resistance between the first membrane electrode (401) and the second electrode plate (302), R PB2 is the resistance of the second electrode plate (302), R GDL2-PB2 is the resistance between the second electrode plate (302) and the second carbon paper (202), R GDL2 is the resistance of the second carbon paper (202), R PRESS2-GDL2 is the resistance between the second pressure head (102) and the second carbon paper (202).

3. A method for testing area specific resistance of a fuel cell according to claim 2, characterized in that: The second resistance value R2 includes: R2=R PRESS1-GDL1 +R GDL1 +R GDL1-PB1 +R PB1 +R PB1-MEA2 +R MEA2 +R PB2-MEA2 +R PB2 +R GDL2-PB2 +R GDL2 +R PRESS2-GDL2 Among them, R PB1-MEA2 is the resistance between the first electrode plate (301) and the second membrane electrode (402), R MEA2 is the resistance of the second membrane electrode, R PB2-MEA2 is the resistance between the second membrane electrode (402) and the second electrode plate (302).

4. A method for testing area specific resistance of a fuel cell according to claim 1, characterized in that: The remaining contact area refers to the effective contact area between the remaining membrane electrode and the membrane electrode after removing the flow channel groove area of ​​the first electrode plate (301) and the second electrode plate (302).

5. A fuel cell area specific resistance testing method according to claim 1, characterized in that: The first pressing head (101) and the second pressing head (102) are made of metal copper, and their surfaces are gold-plated.

6. A method for testing area specific resistance of a fuel cell according to claim 1, characterized in that: The first pressing head (101) and the second pressing head (102) have the same specifications.

7. A method for testing area specific resistance of a fuel cell according to claim 1, characterized in that: The first pressure and the second pressure are between 1 KN and 20 KN, and the first pressure and the second pressure have the same pressure value.

8. A method for testing area specific resistance of a fuel cell according to claim 1, characterized in that: The first voltage and the second voltage have the same voltage value.

9. A method for testing area specific resistance of a fuel cell according to claim 1, characterized in that: The first electrode plate (301) and the second electrode plate (302) have the same specifications.

10. A method for testing area specific resistance of a fuel cell according to claim 1, characterized in that: The first carbon paper (201) and the second carbon paper (202) have the same specifications.

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