Fuel cell test fixture

Abstract

The invention discloses a fuel cell test fixture. The fuel cell test fixture comprises an anode cell shell, a cathode cell shell and a T-shaped probe, the cathode battery shell is configured to be covered with the anode battery shell to jointly define a space for accommodating the single battery, the cathode battery shell comprises a second runner groove and a plurality of second groove plates, and probe grooves are formed in the second groove plates. And the T-shaped probe is used for testing the conductivity of the gas diffusion layer on one side of the cathode of the single cell, the T-shaped probe comprises a transverse section and a vertical section, the transverse section of the T-shaped probe is arranged at the probe groove of the second groove plate, and the vertical section of the T-shaped probe is arranged in the cathode cell shell in a penetrating manner. In a working state, the T-shaped probe corresponds to a cut-off area of the single cell, and the transverse section of the T-shaped probe is used for abutting against a gas diffusion layer on one side of a cathode of the single cell. According to the fuel cell test fixture provided by the embodiment of the invention, the position of the probe groove corresponds to the cut-off gas diffusion layer, so that the real-time performance of detection and the feasibility of online detection are ensured.

Description

Technical Field

[0001] The invention relates to the field of energy and clean technology, in particular to a fuel cell testing fixture. Background Art

[0002] The core components of a fuel cell are composed of three parts: a proton exchange membrane, a catalyst layer, and a gas diffusion layer. The gas diffusion layer plays the role of supporting the catalyst layer, conducting electricity and heat, and regulating the water-gas balance. It is expensive, so it is necessary to study its durability. During the long-term operation of the fuel cell, the gas diffusion layer will undergo mechanical and chemical degradation. Mechanical degradation includes irreversible mechanical damage caused by compression, freeze-thaw, water dissolution, and airflow erosion; chemical degradation is mainly due to the reaction of carbon with water and being washed away under certain conditions, causing the gas diffusion layer structure to collapse. Since the gas diffusion layer has a longer lifespan than other structural components of the fuel cell, simulating the lifespan prediction and attenuation mode analysis of the gas diffusion layer under normal working conditions has proven to be a very valuable test method.

[0003] However, the aging research on gas diffusion layers is concentrated on offline accelerated experiments. Offline accelerated experiments simulate the degradation mechanism of the gas diffusion layer and directly use physical or chemical means on the gas diffusion body. However, the results of offline accelerated experiments are difficult to link with the attenuation of the gas diffusion layer under the actual battery operation conditions, and it is not possible to conclude the extent of the impact of gas diffusion layer attenuation on battery performance after actual durability testing. At the same time, some research data also show that there may be a big gap between the results of offline and online durability tests. The online durability test currently used to quantitatively analyze the attenuation of the gas diffusion layer often tries to separate the aged gas diffusion layer, reassemble the battery for performance testing and analysis, and then determine the contribution of the gas diffusion layer to the performance attenuation of the entire fuel cell.

[0004] The so-called "online" tests mentioned above to study the impact of gas diffusion layer attenuation on battery performance are actually conducted after the accelerated aging test, focusing on later performance data or disassembling the battery to separate the gas diffusion layer. It is impossible to "truly" detect the aging process of the gas diffusion layer in real time and online, and it is impossible to truly establish the relationship between the preparation parameters and the life of the gas diffusion layer. At the same time, the process of disassembling the battery to separate the gas diffusion layer will also cause varying degrees of physical damage to the gas diffusion layer, which is not conducive to further aging research on the gas diffusion layer. Therefore, a new fuel cell test fixture is urgently needed to overcome the inability of existing test methods to fully reflect the aging process of the gas diffusion layer in real time.

[0005] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] The object of the present invention is to provide a fuel cell test fixture, which can simulate the use environment of the fuel cell in real time and more accurately detect the aging process of the gas diffusion layer.

[0007] To achieve the above-mentioned purpose, an embodiment of the present invention provides a fuel cell test fixture for testing the aging degree of a single cell in a fuel cell. The fuel cell test fixture includes an anode battery shell, a cathode battery shell and a "T"-shaped probe. The anode battery shell includes a first flow channel groove and a plurality of first slot plates, and the first flow channel groove and the plurality of first slot plates together form a first flow channel. The cathode battery shell is configured to be covered with the anode battery shell to jointly enclose a space for accommodating the single cell, and the cathode battery shell includes a second flow channel groove and a plurality of second slot plates, and the second flow channel groove and the plurality of second slot plates together form a second flow channel, and the second slot plate has a probe groove. The "T"-shaped probe is used to test the conductivity of the gas diffusion layer on the cathode side of a single cell. The "T"-shaped probe includes a horizontal section and a vertical section fixed to the center of the horizontal section. The horizontal section of the "T"-shaped probe is arranged at the probe slot of the second slot plate, and the vertical section of the "T"-shaped probe passes through the cathode battery shell. In the working state, the "T"-shaped probe corresponds to the cut-off area of ​​the single cell, and the horizontal section of the "T"-shaped probe is used to abut the gas diffusion layer on the cathode side of the single cell.

[0008] In one or more embodiments of the present invention, the “T”-shaped probe is insulated from the cathode battery case, the probe groove cuts off the second groove plate, and there is a gap between the “T”-shaped probe and the cut-off second groove plate.

[0009] In one or more embodiments of the present invention, an insulating pad is provided between the transverse section of the “T”-shaped probe and the second flow channel groove.

[0010] In one or more embodiments of the present invention, a circular through hole matching the vertical section of the "T"-shaped probe is provided on the cathode battery shell, and the vertical section of the "T"-shaped probe is provided with an insulating rubber sleeve, which is passed through and fixed in the circular through hole.

[0011] In one or more embodiments of the present invention, the number of the “T”-shaped probes is four.

[0012] In one or more embodiments of the present invention, the fuel cell test fixture further includes a conductivity detector, and one end of the “T”-shaped probe is connected to the conductivity detector.

[0013] In one or more embodiments of the present invention, a four-pole double-throw switch connected to the "T"-shaped probe is further included, wherein the four-pole double-throw switch includes a "0" position and a "1" position, wherein the "0" position is connected to the conductivity detector, and the "1" position is connected to the cathode battery shell.

[0014] In one or more embodiments of the present invention, the four-pole double-throw switch switches at four levels simultaneously. When the four-pole double-throw switch is turned on the "0" position, the conductivity detector is connected to the four "T"-type probes, and the conductivity detector and the four "T"-type probes are insulated from the cathode battery shell and are used to test the conductivity of the gas diffusion layer in the cut-off area of ​​the single cell; when the four-pole double-throw switch is turned on the "1" position, the four "T"-type probes are connected in series with the cathode battery shell, and are used to perform normal aging tests on the gas diffusion layer in the cut-off area of ​​the single cell.

[0015] In one or more embodiments of the present invention, the fuel cell test fixture also includes a contact angle detector, which includes a syringe, a syringe needle and a fixing assembly arranged on the syringe, the fixing assembly includes a fixing screw, a sealing rubber sleeve and a locking nut, and a threaded hole is provided on the cathode battery shell, and a center through hole is opened at the center of the bottom surface of the threaded hole, and the center through hole is used to insert the syringe needle, and the threaded hole is used to cooperate with the fixing assembly to seal the fuel cell test fixture.

[0016] In one or more embodiments of the present invention, observation grooves connected to the second flow channel are arranged on both sides of the second flow channel, and the observation grooves are provided with quartz window plates. Fixed steel plates are arranged on both sides of the cathode battery shell, and each of the fixed steel plates is provided with an observation window.

[0017] Compared with the prior art, the fuel cell test fixture of this embodiment has a probe slot on the second slot plate, which perfectly integrates the probe with the battery shell flow channel. The position of the probe slot corresponds to the truncated gas diffusion layer, so that the test environment of the truncated gas diffusion layer to be tested is basically consistent with that of the overall gas diffusion layer, ensuring the real-time detection and the feasibility of online detection; the conductivity of the gas diffusion layer is tested by designing a four-pole double-throw switch, and the gas diffusion layer can also be subjected to a normal aging test; a fixing component is set on the structure of an existing contact angle tester, a threaded hole is set on the cathode battery shell to cooperate with the fixing component, a central through hole and an observation window are set to detect the contact angle of the gas diffusion layer, and the aging process of the gas diffusion layer is analyzed in conjunction with the conductivity; the present invention can be improved on the basis of the existing fuel cell test fixture, is relatively simple to operate, and saves resources, and does not require the preparation of a new test fixture. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of a cathode battery shell structure and a "T"-shaped probe structure according to one embodiment of the present invention;

[0019] Figure 2 yes Figure 1 A magnified view of the structure at center;

[0020] Figure 3 is a schematic diagram of the structure of the second flow channel groove according to one embodiment of the present invention;

[0021] Figure 4 is a schematic diagram of a single cell structure according to an embodiment of the present invention;

[0022] Figure 5 Schematic diagram of the structure of an anode battery shell according to one embodiment of the present invention;

[0023] Figure 6 Schematic diagram of the overall structure of a cathode battery shell according to one embodiment of the present invention;

[0024] Figure 7 yes Figure 6 A magnified view of the structure at C in the middle;

[0025] Figure 8 It is a schematic diagram of the connection relationship between a conductivity detector, a four-pole double-throw switch and a cathode battery shell according to one embodiment of the present invention;

[0026] Fig. 9 is a schematic diagram of the overall structure of a fuel cell fixture according to one embodiment of the present invention;

[0027] Fig.10 is a schematic diagram of a cathode battery case from another perspective according to one embodiment of the present invention;

[0028] Fig.11 yes Fig.10 Exploded view of the structure at D in the middle;

[0029] Fig.12 is a schematic diagram of the cathode battery shell structure of another embodiment of the present invention;

[0030] Fig.13 is a schematic diagram of observation at an observation window according to an embodiment of the present invention;

[0031] Fig.14 Schematic diagram of the droplet observation principle according to one embodiment of the present invention;

[0032] Description of main reference numerals:

[0033] 1-anode battery shell, 11-first flow channel groove, 12-first groove plate, 13-first flow channel,

[0034] 2- cathode battery shell, 21- second flow channel groove, 22- second groove plate, 221- probe groove, 23- second flow channel, 24- circular through hole, 25- threaded hole, 26- center through hole, 27- observation groove, 271- quartz window plate, 28- fixed steel plate, 281- observation window,

[0035] 3-"T" type probe, 31-horizontal section, 32-vertical section, 33-insulating rubber sleeve,

[0036] 4-conductivity detector, 5-four-pole double-throw switch, 61-syringe, 62-syringe needle, 63-fixing assembly, 631-fixing screw, 632-sealing rubber sleeve, 633-locking nut, 7-liquid drop, 8-single battery. DETAILED DESCRIPTION

[0037] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0038] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0039] Most of the life studies of gas diffusion layers are focused on offline accelerated aging, which is too far from the actual working environment of the battery, and it is difficult to establish an accurate gas diffusion layer life evaluation mechanism. The aging performance of the gas diffusion layer is mainly reflected in two aspects: the elastic modulus of the gas diffusion layer decreases, the pressure it is subjected to decreases, which will increase the contact resistance, increase the ohmic polarization of the fuel cell, and reduce the battery performance; the hydrophobicity of the gas diffusion layer decreases, and its water management ability decreases, which hinders the transmission of the reaction gas, increases the diffusion polarization, and reduces the battery performance. Among them, the elastic modulus of the gas diffusion layer is mainly based on the conductivity test data, and the hydrophobicity of the gas diffusion layer is mainly based on the contact angle test data. The present invention is based on the test of the above two data to complete the real-time, online aging process analysis of the gas diffusion layer. After the external fuel cell test platform is connected, according to the different conditions of compression, freeze-thaw, water dissolution, airflow erosion, start-stop, and variable load of the gas diffusion layer degradation, the relationship between the change law of the contact angle and conductivity of the gas diffusion layer under different accelerated attenuation conditions and working conditions and the battery performance and the life of the gas diffusion layer is monitored online, and then the preparation parameters that need to be improved and improved can be found from the perspective of gas diffusion layer preparation.

[0040] like Figures 1 to 14As shown, a fuel cell test fixture according to a preferred embodiment of the present invention includes an anode battery shell 1, a cathode battery shell 2 and a "T"-shaped probe 3. The fuel cell test fixture is used to test the aging degree of a single cell in a fuel cell. The anode battery shell 1 includes a first flow channel groove 11 and a plurality of first groove plates 12, and the first flow channel groove 11 and the plurality of first groove plates 12 together form a first flow channel 13. The cathode battery shell 2 is configured to be covered with the anode battery shell 1 to jointly enclose a space for accommodating a single cell 8, and the cathode battery shell 2 includes a second flow channel groove 21 and a plurality of second groove plates 22, and the second flow channel groove 21 and the plurality of second groove plates 22 together form a second flow channel 23, and a probe groove 221 is provided on the second groove plate 22. The "T"-shaped probe 3 is used to test the conductivity of the gas diffusion layer on the cathode side of the single cell 8. The "T"-shaped probe 3 includes a transverse section 31 and a vertical section 32 fixed to the center of the transverse section 31. The transverse section 31 of the "T"-shaped probe 3 is arranged at the probe slot 221 of the second slot plate 22, and the vertical section 32 of the "T"-shaped probe 3 is passed through the cathode battery shell 2. In the working state, the transverse section 31 of the "T"-shaped probe 3 corresponds to the cut-off area of ​​the single cell 8, and the transverse section 31 of the "T"-shaped probe 3 is used to abut the gas diffusion layer on the cathode side of the single cell 8.

[0041] In the fuel cell test fixture of this embodiment, a probe slot 221 is set on the second slot plate 22, and the shape of the probe is set to a "T"-shaped probe, which perfectly integrates the probe with the second flow channel 23 of the cathode battery shell 2. The position of the probe slot 221 corresponds to the truncated gas diffusion layer, so that the test environment of the truncated gas diffusion layer to be tested is basically consistent with that of the overall gas diffusion layer, ensuring the real-time detection and the feasibility of online detection. The present invention can be improved on the basis of the existing fuel cell test fixture, without the need to prepare a new test fixture, saving resources, and the test operation is relatively simple.

[0042] like Figure 1 , Figure 3 and Figure 4 As shown, Figure 4 In the figure, region B is the truncated gas diffusion layer region. When the fuel cell test fixture is used to test the conductivity, a single cell 8 is placed in the fuel cell test fixture, wherein the single cell 8 includes a membrane electrode and a gas diffusion layer disposed on both sides of the membrane electrode. There is a truncated region B on the gas diffusion layer on the cathode side, and the truncated region B corresponds to the position of the "T"-shaped probe 3. The cross section 31 of the "T"-shaped probe 3 can abut against the truncated gas diffusion layer, thereby testing the conductivity of the gas diffusion layer on the cathode side.

[0043] For the test of the conductivity of the gas diffusion layer, it is necessary to ensure the insulation between the "T"-shaped probe 3 and the cathode battery shell 2. Specifically, the probe groove 221 cuts off the second slot plate 22, and there is a gap between the cross section 31 of the "T"-shaped probe 3 and the cut-off second slot plate 22. In some embodiments, an insulating pad (not shown in the figure) is provided between the cross section 31 of the "T"-shaped probe 3 and the second flow channel groove 21 to ensure the insulation effect between the cross section 31 of the "T"-shaped probe 3 and the cathode battery shell 2.

[0044] like Figure 1 As shown, in some embodiments, the cathode battery shell 2 has a circular through hole 24 that is compatible with the vertical section 32 of the "T"-shaped probe 3. An insulating rubber sleeve 33 is provided on the vertical section 32 of the "T"-shaped probe 3, which is passed through and fixed at the circular through hole 24. By providing a gap between the horizontal section 31 and the truncated second slot plate 22, providing an insulating pad between the horizontal section 31 and the second flow channel groove 21, and filling the vertical section 32 and the circular through hole 24 with an insulating rubber sleeve, the "T"-shaped probe and the cathode battery shell 2 are ensured to be insulated as a whole.

[0045] like Figure 1 , Figure 3 and Figure 8 As shown, generally speaking, the conductivity can be tested by a conductivity detector 4, and a four-probe conductivity detector is a commonly used device. Accordingly, four "T"-shaped probes 3 also need to be provided.

[0046] Specifically, Figure 8 As shown, in order to ensure sufficient test data, a four-pole double-throw switch 5 is provided between the conductivity detector 4 and the "T"-shaped probe 3, wherein the four-pole double-throw switch 5 has two positions, namely, the "0" position and the "1" position. One end of the four-pole double-throw switch 5 is connected to the four "T"-shaped probes 3, the "0" position of the four-pole double-throw switch 5 is connected to the conductivity detector 4, and the "1" position of the four-pole double-throw switch 5 is connected to the cathode battery shell 2.

[0047] Considering the convenience of switch switching, the four-pole double-throw switch 5 four-pole switch is switched simultaneously. Figure 8 As shown, when the 4-pole double-throw switch 5 is in the "0" position, the conductivity detector 4 is connected to the four "T" type probes 3, and the conductivity detector 4 and the four "T" type probes 3 are insulated from the cathode battery shell 2. The conductivity detector 4 is used to test the conductivity of the gas diffusion layer in the cut-off area of ​​the single cell 8; when the 4-pole double-throw switch 5 is in the "1" position, the four "T" type probes 3 are connected in series with the cathode battery shell 2, and are used to perform a normal aging test on the gas diffusion layer in the cut-off area of ​​the single cell 8. Among them, the cut-off gas diffusion layer is the gas diffusion layer on the cathode side.

[0048] like Figure 1 , Figure 7 , Fig. 9 , Fig.10 and Fig.11 As shown, in one embodiment, 13.4mm is cut off on the four second slot plates 22 connected to the cathode battery shell 2 to form four probes 221. A through circular through hole 24 is provided in the center of each probe slot 221. The bottom diameter of each center through hole 24 is 2mm. The vertical section 32 of the "T"-shaped probe 3 has a size of 1mm×1mm×27.5mm, the length of the horizontal section 31 is 13mm, the width of the horizontal section 31 is consistent with the width of the second slot plate 22, which is 1mm, and the height is 0.85mm. The spacing between the horizontal section 31 of the "T"-shaped probe 3 and the cut-off second slot plate 22 is 0.2mm for insulation. An insulating pad with a thickness of 0.15mm is set between the horizontal section 31 and the cathode battery shell 2. The vertical section 32 is covered with an insulating rubber sleeve 33 on the outside and embedded in the circular through hole 24 to be fully fixed, so as to achieve the insulation between the "T"-shaped probe 3 and the cathode battery shell 2.

[0049] like Figure 6 As shown, the cleverness of this design lies in the perfect integration of the design of the "T"-shaped probe 3 and the second flow channel 23 of the cathode battery shell 2. When the conductivity of the gas diffusion layer on the cathode side is tested, the test environment of the gas diffusion layer area to be tested is basically consistent with the test environment of the entire aged gas diffusion layer, ensuring the real-time and accuracy of online detection.

[0050] Secondly, the contact angle of the gas diffusion layer is tested. Fig.10 As shown, in some embodiments, the fuel cell test fixture also includes a contact angle detector. When the contact angle detector is used for detection, the cathode battery shell 2 needs to be punched and sealed. Specifically, the contact angle detector includes a syringe 61, a syringe needle 62, and a fixing assembly 63 arranged on the syringe 61. The fixing assembly 63 includes a fixing screw 631, a sealing rubber sleeve 632, and a locking nut 633, wherein the locking nut 633 is a downward locking sealing rubber sleeve nut. There is a threaded hole 25 on the cathode battery shell 2. In one embodiment, the size of the threaded hole 25 is M6 and the depth is 10mm. The threaded hole 25 is not through, and a central through hole 27 with a diameter of 1mm is provided on the bottom surface of the threaded hole 25. The central through hole 27 is used to insert the syringe needle 62 of the contact angle detector into the battery shell and drip a droplet 7 on the gas diffusion layer on the cathode side. The diameter of the syringe needle 62 is 0.5mm. When the downward locking sealing rubber sleeve nut is tightened, the syringe needle 62 is fixed and locked, and at the same time plays a sealing role.

[0051] like Figure 6 , Fig.12As shown, in order to facilitate the detection of the contact angle of the droplet 7, observation grooves 27 are provided on both sides of the second flow channel of the cathode battery shell, and the observation grooves 27 are connected to the second flow channel 23. A quartz window piece 271 matching the size of the observation groove 27 is provided in the observation groove 27. In this embodiment, the optical path is opened by providing the quartz window piece 271, which facilitates the imaging of the droplet and data collection by the light source and camera of the contact angle detector. In addition to the quartz window piece 271, other optical parts with excellent light transmission effect can also be used. Specifically, Fig.12 In the figure, the dotted line direction is the direction of the light path.

[0052] In one embodiment, the quartz window 271 has a size of 23 mm×7 mm×11 mm, wherein the two planes of 7 mm×11 mm (i.e., the planes through which the light path passes) are set to be mirror-transmissive, and the remaining planes are frosted to facilitate the glue to adhere to the entire battery shell. After the quartz window 271 is bonded with the sealant, a fixed steel sheet 28 is set on the outside to seal the quartz window 271.

[0053] In order to facilitate observation, an observation window 281 is provided on the fixed steel sheet 28. Specifically, Fig.13 As shown in FIG. 1 , it is a schematic diagram of observation at the observation window, which simulates the imaging of a 1 μL droplet injected by a contact angle tester syringe. The maximum diameter of the 1 μL droplet is 1.3 mm, which is smaller than the width of the second flow channel 23 of 3 mm. Fig.14 As shown, the light source and camera of the contact angle detector are respectively arranged at the observation windows 281 on both sides, wherein the left side is the light source and the right side is the camera.

[0054] Compared with the general single cell test, the output is the polarization curve, CV curve, impedance, current, voltage and power of the entire membrane electrode. In this embodiment, in addition to the above data, the contact angle and conductivity of the cathode gas diffusion layer can also be output.

[0055] Through the above technical solution, the ordinary fuel cell fixture is successfully combined with the four-probe conductivity test and contact angle test functions to output the conductivity and contact angle data of the gas diffusion layer to be tested in real time and online during the accelerated aging process.

[0056] Compared with the offline accelerated aging adopted in most gas diffusion layer aging research, the present invention adopts online accelerated aging research to truly simulate the aging of the gas diffusion layer under the operating conditions of the fuel cell, which can be linked to the attenuation of the gas diffusion layer under the actual battery operating conditions, and the degree of influence of the gas diffusion layer attenuation on the battery performance after the actual durability test can be obtained, which can more deeply understand and improve the durability of the gas diffusion layer and establish an accurate evaluation of the durability of the gas diffusion layer.

[0057] Compared with most online aging studies of gas diffusion layers, it can output the two main performance parameters of the gas diffusion layer, contact angle and conductivity, at any time point in the accelerated aging process without having to interrupt the test or disassemble the battery to separate the gas diffusion layer for research. This allows "truly" real-time, online detection of the aging process of the gas diffusion layer and truly establishes the relationship between the preparation parameters of the gas diffusion layer and its life.

[0058] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A fuel cell test fixture, used to test the aging degree of the gas diffusion layer of a single cell in a fuel cell, characterized in that: The fuel cell test fixture includes: An anode battery shell, comprising a first flow channel groove and a plurality of first groove plates, wherein the first flow channel groove and the plurality of first groove plates together form a first flow channel; A cathode battery case, configured to be covered with the anode battery case to enclose a space for accommodating the single battery, the cathode battery case comprising a second flow channel groove and a plurality of second groove plates, the second flow channel groove and the plurality of second groove plates together forming a second flow channel, and the second groove plate having a probe groove; and A "T"-shaped probe, used to test the conductivity of the gas diffusion layer on the cathode side of a single cell, the "T"-shaped probe comprising a horizontal section and a vertical section fixed to the center of the horizontal section, the horizontal section of the "T"-shaped probe being arranged at the probe slot of the second slot plate, and the vertical section of the "T"-shaped probe being passed through the cathode battery shell; In the working state, the "T"-shaped probe corresponds to the cut-off area of ​​the single cell, and the transverse section of the "T"-shaped probe is used to abut against the gas diffusion layer on the cathode side of the single cell.

2. The fuel cell test fixture according to claim 1, characterized in that: The “T”-shaped probe is insulated from the cathode battery shell, the probe groove cuts off the second groove plate, and there is a gap between the “T”-shaped probe and the cut-off second groove plate.

3. The fuel cell test fixture as claimed in claim 2, characterized in that: An insulating pad is arranged between the transverse section of the "T"-shaped probe and the second flow channel groove.

4. The fuel cell test fixture according to claim 1, characterized in that: The cathode battery shell is provided with a circular through hole matched with the vertical section of the "T"-shaped probe, and the vertical section of the "T"-shaped probe is provided with an insulating rubber sleeve, which is passed through and fixed in the circular through hole.

5. The fuel cell test fixture as claimed in claim 1, characterized in that: The "T"-shaped probe has four.

6. The fuel cell test fixture as claimed in claim 5, characterized in that: It also includes a conductivity detector, and one end of the "T"-shaped probe is connected to the conductivity detector.

7. The fuel cell test fixture as claimed in claim 6, characterized in that: It also includes a four-pole double-throw switch connected to the "T"-shaped probe, the four-pole double-throw switch includes a "0" position and a "1" position, the "0" position is connected to the conductivity detector, and the "1" position is connected to the cathode battery shell.

8. The fuel cell test fixture as claimed in claim 7, characterized in that: The four-pole double-throw switch switches at four levels simultaneously. When the four-pole double-throw switch is in the "0" position, the conductivity detector is connected to the four "T"-type probes. The conductivity detector and the four "T"-type probes are insulated from the cathode battery shell and are used to test the conductivity of the gas diffusion layer in the cut-off area of ​​the single cell. When the four-pole double-throw switch is in the "1" position, the four "T"-type probes are connected in series with the cathode battery shell to perform a normal aging test on the gas diffusion layer in the cut-off area of ​​the single cell.

9. The fuel cell test fixture according to claim 1, characterized in that: It also includes a contact angle detector, which includes a syringe, a syringe needle and a fixing assembly arranged on the syringe, the fixing assembly includes a fixing screw, a sealing rubber sleeve and a locking nut, a threaded hole is arranged on the cathode battery shell, a center through hole is opened at the center of the bottom surface of the threaded hole, the center through hole is used to insert the syringe needle, and the threaded hole is used to cooperate with the fixing assembly to seal the fuel cell test fixture.

10. The fuel cell test fixture according to claim 9, characterized in that: Observation grooves communicating with the second flow channel are arranged on both sides of the second flow channel, and the observation grooves are provided with quartz window plates. Fixed steel plates are arranged on both sides of the cathode battery shell, and each of the fixed steel plates is provided with an observation window.

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