A kind of hydrogen fuel cell gas diffusion layer gas permeability detection equipment

Abstract

The present application relates to hydrogen fuel cell technology field, specifically is related to a kind of gas diffusion layer of hydrogen fuel cell gas permeability detection equipment;Including: rack;Limit observation module, horizontal fixed setting in the rack, it includes a fixed detection bin under gas diffusion layer and an openable and closable movable detection bin on gas diffusion layer;Detection medium output module, set in the bottom of the fixed detection bin, for output detection medium in the fixed detection bin;Reaction medium output module, set in the movable detection bin, for output reaction medium in the movable detection bin can occur color reaction with the detection medium;Detection module, set in the movable detection bin, its detection end is vertically towards the upper surface of the gas diffusion layer setting;The present application can not only realize the efficient clamping of gas diffusion layer and can realize the comprehensive, high-precision dead angle-free detection of gas diffusion layer.

Description

Technical Field

[0001] This invention relates to the field of hydrogen fuel cell technology, specifically to a device for testing the permeability performance of a gas diffusion layer in a hydrogen fuel cell. Background Technology

[0002] As a key functional material in the membrane electrode assembly of hydrogen fuel cells, the gas diffusion layer's microporous structure, areal density, and permeability directly affect the transport efficiency of hydrogen, oxygen, and water vapor within the cell, thus determining the fuel cell's output performance, stability, and lifespan. Therefore, precise, reliable, and repeatable testing of its permeability is essential during the production and quality control of the gas diffusion layer.

[0003] However, existing air permeability testing equipment generally suffers from problems such as simple structure, crude clamping methods, and unstable testing conditions. Firstly, conventional testing equipment typically employs simple clamping or end-point clamping structures. Because these cannot adequately flatten the gas diffusion layer and maintain uniform force during clamping, they easily lead to wrinkles, localized warping, or edge bending on the material surface, causing uneven force distribution in the tested area and introducing additional resistance, resulting in larger errors in the test data. Furthermore, traditional air permeability testing devices are generally crude in their airflow introduction methods, detection hole distribution, and test chamber structure design. Most rely solely on single-point or single-channel airflow to evaluate the diffusion layer, failing to achieve uniform air permeability testing across the entire surface area. This results in detection blind spots, concentrated flow areas, or low-sensitivity detection zones, failing to accurately reflect the true air permeability uniformity and overall diffusion performance of the gas diffusion layer. Simultaneously, conventional testing equipment has low pressure regulation and flow detection sensitivity, making it difficult to respond accurately to minute changes in gas diffusion layer permeability, leading to large dispersion and insufficient repeatability in measurement results. Summary of the Invention

[0004] To address the aforementioned issues, a permeability testing device for the gas diffusion layer of a hydrogen fuel cell is provided. This device reliably flattens and fixes the gas diffusion layer, achieves uniform airflow distribution across the entire area, and possesses high sensitivity and high precision testing capabilities. This solves the technical problems of existing permeability testing devices, such as localized blind spots, poor testing stability, and low accuracy.

[0005] To address the problems of existing technologies, this invention provides a device for testing the permeability of a hydrogen fuel cell gas diffusion layer, comprising: a frame; a limiting observation module, horizontally fixed on the frame for clamping the gas diffusion layer to be tested, which includes a fixed detection chamber located below the gas diffusion layer and a movable detection chamber located on the gas diffusion layer and capable of opening and closing; a detection medium output module, located at the bottom of the fixed detection chamber for outputting a detection medium into the fixed detection chamber; a reaction medium output module, located within the movable detection chamber for outputting a reaction medium that can react with the detection medium to the movable detection chamber; and a detection module, located within the movable detection chamber, with its detection end vertically facing the upper surface of the gas diffusion layer; wherein, during testing, the detection medium, driven by pressure, permeates through the gas diffusion layer, enters the movable detection chamber, and contacts the reaction medium to undergo a color reaction, and the detection module evaluates the permeability of the gas diffusion layer by capturing changes in the color development area;

[0006] The detection medium output module also includes a first linear driver capable of driving the push plate to slide longitudinally within the fixed detection chamber and a first supply pipe capable of supplying detection medium into the output head in real time.

[0007] The reaction medium output module further includes an isolation plate that can isolate the detection module when the reaction medium is introduced into the active detection chamber, and a second output unit that is fixedly disposed at the bottom of the isolation plate and can introduce the reaction medium into the active detection chamber; the isolation plate is slidably inserted and removed from the middle of the active detection chamber;

[0008] The second discharge unit is equipped with a sieve plate that can store the reaction medium and a vibrator that can actively cause the sieve plate to vibrate and discharge the reaction medium; the sieve plate is horizontally fixed on the lower surface of the isolation plate; there are two vibrators, which are fixedly arranged on both sides of the lower surface of the isolation plate.

[0009] Preferably, the first export unit is provided with a spray head capable of exporting the reaction medium toward the active detection chamber and a second supply pipe capable of introducing the reaction medium into the spray head.

[0010] Preferably, the limiting observation module further includes a fixed frame and a second linear actuator capable of driving the movable detection chamber longitudinally away from or towards the fixed detection chamber; two second linear actuators are provided, and the two second linear actuators are vertically arranged opposite each other on both sides of the frame through the fixed frame, with the drive end passing through the fixed frame and fixedly connected to the movable detection chamber.

[0011] Preferably, the top two sides of the fixed detection chamber are respectively provided with a first adsorption hole and a second adsorption hole capable of adsorbing the gas diffusion layer.

[0012] Preferably, the detection module further includes a guide rod capable of horizontally guiding the detection head to adjust the detection position and a supplementary light capable of providing supplementary illumination to the detection area when the detection head detects the gas diffusion layer; the guide rod is horizontally fixedly installed inside the movable detection chamber and is positioned near the top of the movable detection chamber; the detection head is vertically slidably installed on the guide rod; two supplementary lights are provided, and the two supplementary lights are fixedly installed relative to each other inside the movable detection chamber.

[0013] The advantages of this invention compared to the prior art are:

[0014] 1. This invention utilizes a synergistic clamping structure between a fixed detection chamber and a movable detection chamber, and provides a first adsorption hole and a second adsorption hole on the top two sides of the movable detection chamber that communicate with an external suction device. This allows for pre-stretching and pre-positioning of the gas diffusion layer before clamping, ensuring that the gas diffusion layer remains horizontally stretched, wrinkle-free, and unbent during the detection process. This effectively avoids the problems of local gas retention and detection distortion caused by material warping in existing equipment, fundamentally improving the stability and repeatability of permeability test data.

[0015] 2. This invention uses steam as the detection medium and, through the combined structure of a steam generator, a first supply pipe, an output head, and a pusher plate, enables steam to quickly fill the fixed detection chamber and penetrate the microporous structure of the gas diffusion layer at a constant pressure under the pressurization of the pusher plate. Compared with the local non-penetration and detection blind spots caused by the natural diffusion method in the prior art, this invention can ensure that the detection medium penetrates uniformly throughout the entire material surface area, effectively avoiding dead zones in air permeability detection and achieving highly sensitive and highly consistent air permeability analysis.

[0016] 3. This invention utilizes the coordinated operation of a first outlet unit, a second outlet unit, a vibrator, and a sieve plate or spray head to ensure uniform coverage of the reaction medium on the surface of the gas diffusion layer. Combined with color-developing materials such as dry powder or cobalt chloride, it produces a noticeable reaction after water vapor penetration, thereby enabling a visual assessment of air permeability. Unlike existing technologies where uneven spraying leads to localized color abnormalities, this invention ensures uniform reaction layer thickness and allows for intuitive presentation of reaction changes, improving the resolution, comparability, and reliability of air permeability testing results.

[0017] 4. This invention is equipped with a high-sensitivity detection head and supplementary light. The detection head continuously records the real-time color development or wetting changes of the reaction medium and vapor, and can comprehensively monitor the air permeability behavior of each area of ​​the gas diffusion layer. Compared with the existing equipment, which can only perform local sampling or cannot perform real-time imaging, this invention can achieve dynamic detection of the entire area without blind spots or dead angles, which greatly improves the scientific nature of air permeability evaluation. Attached Figure Description

[0018] Figure 1 This is a three-dimensional diagram of a device for testing the permeability of a hydrogen fuel cell gas diffusion layer.

[0019] Figure 2 This is a front view of a device for testing the permeability of a hydrogen fuel cell gas diffusion layer.

[0020] Figure 3 yes Figure 2 Sectional view at point AA.

[0021] Figure 4 This is a top view of a device for testing the permeability of a hydrogen fuel cell gas diffusion layer.

[0022] Figure 5 yes Figure 4 A three-dimensional sectional view of the section at point BB.

[0023] Figure 6 yes Figure 5 A magnified view of a portion of point C.

[0024] Figure 7 This is a left-angle exploded view of a device for testing the permeability of a hydrogen fuel cell gas diffusion layer.

[0025] Figure 8 This is a top-down exploded view of a device for testing the permeability of a hydrogen fuel cell gas diffusion layer.

[0026] The numbers on the map are:

[0027] 1. Frame; 11. Gas diffusion layer;

[0028] 2. Limit observation module; 21. Fixed detection chamber; 22. Moving detection chamber; 221. First adsorption hole; 222. Second adsorption hole; 23. Second linear actuator; 24. Fixing frame;

[0029] 3. Detection medium output module; 31. Output head; 32. Push plate; 33. First linear driver; 34. First supply pipe;

[0030] 4. Reaction medium output module; 41. First outlet unit; 411. Spray head; 412. Second supply pipe; 42. Isolation plate; 43. Second outlet unit; 431. Sieve plate; 432. Vibrator;

[0031] 5. Detection module; 51. Detection head; 52. Guide rod; 53. Fill light. Detailed Implementation

[0032] To further understand the features, technical means, and specific objectives and functions achieved by the present invention, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0033] See Figures 1 to 8 The following is a device for testing the permeability of a hydrogen fuel cell gas diffusion layer: a frame 1; a limiting observation module 2, horizontally fixed on the frame 1, for clamping the gas diffusion layer 11 to be tested, which includes a fixed detection chamber 21 located below the gas diffusion layer 11 and a movable detection chamber 22 located on the gas diffusion layer 11 and openable / closable; a detection medium output module 3, located at the bottom of the fixed detection chamber 21, for outputting a detection medium into the fixed detection chamber 21; a reaction medium output module 4, located in the movable detection chamber 22, for outputting a reaction medium that can react with the detection medium to the movable detection chamber 22; and a detection module 5, located in the movable detection chamber 22, with its detection end vertically facing the upper surface of the gas diffusion layer 11. During testing, the detection medium, driven by pressure, permeates through the gas diffusion layer 11, enters the movable detection chamber 22, and reacts with the reaction medium to produce a color reaction. The detection module 5 evaluates the permeability of the gas diffusion layer 11 by capturing changes in the color development area. The gas diffusion layer has good permeability; the detection medium output module 3 also includes a first linear actuator 33 that can drive the push plate 32 to slide longitudinally in the fixed detection chamber 21 and a first supply pipe 34 that can supply the detection medium to the output head 31 in real time; the reaction medium output module 4 also includes an isolation plate 42 that can isolate the detection module 5 when the reaction medium is introduced into the movable detection chamber 22 and a second outlet unit 43 that is fixedly set at the bottom of the isolation plate 42 and can introduce the reaction medium into the movable detection chamber 22; the isolation plate 42 is slidably inserted and removed in the middle of the movable detection chamber 22; the second outlet unit 43 is provided with a sieve plate 431 that can store the reaction medium and a vibrator 432 that can actively cause the sieve plate 431 to vibrate and export the reaction medium; the sieve plate 431 is horizontally fixedly set on the lower surface of the isolation plate 42; there are two vibrators 432, which are fixedly set on both sides of the lower surface of the isolation plate 42.

[0034] Both the fixed detection chamber 21 and the movable detection chamber 22 are hollow rectangular shells with openings at both ends.

[0035] When the permeability of the gas diffusion layer 11 needs to be tested, the operator first takes out the gas diffusion layer 11 to be tested and accurately places it into the clamping position between the fixed testing chamber 21 and the movable testing chamber 22. This clamping mechanism ensures the gas diffusion layer 11 is flat and properly positioned, maintaining a stable testing posture without wrinkles or obstructions. After clamping, the first delivery unit 41 is activated to uniformly deliver the reaction medium to the upper surface of the gas diffusion layer 11, ensuring that the reaction medium forms a uniformly spread initial state across the entire diffusion layer surface.

[0036] Subsequently, the detection medium output head 31 is driven to operate, and the detection medium, such as vapor, is introduced into the fixed detection chamber 21 through the output head 31 until the detection space is filled. Then, the push plate 32 is further driven to push vertically from bottom to top, so that the detection medium inside the fixed detection chamber 21 penetrates the microporous structure inside the gas diffusion layer 11 under stable pressure under the continuous pressurization of the push plate 32, and is finally completely introduced into the movable detection chamber 22. During this process, the detection module 5 records the color development or wetting reaction caused by the contact between the reaction medium on the surface of the diffusion layer and the detection medium in real time. By analyzing the reaction duration, reaction area distribution and reaction intensity, a comprehensive evaluation of the overall air permeability uniformity, air permeability speed and local air permeability differences of the gas diffusion layer 11 is achieved.

[0037] The detection medium and reaction medium are water vapor and dry powder, respectively. Water vapor penetrates the diffusion layer and triggers a wetting change in the dry powder. To further enhance the development effect, cobalt chloride powder can be used as the reaction medium. When water vapor molecules penetrate the diffusion layer, they enter the powder surface and undergo a complexation reaction with cobalt chloride, gradually changing from a deep blue to a pink hexahydrate cobalt chloride crystalline phase. In areas with good air permeability, this colorimetric reaction occurs rapidly and uniformly, making the overall air permeability distribution easier to observe and record.

[0038] The above process enables high-precision detection of the gas diffusion layer 11's permeability across the entire area and throughout the entire process, avoiding blind spots in detection, and providing intuitive and visual permeability measurement results through colorimetric reactions, thereby improving detection sensitivity and reliability.

[0039] At least two output heads 31 are provided, and the two output heads 31 are embedded in each other on both sides of the fixed detection chamber 21 with their output ends passing through the fixed detection chamber 21 and facing into the fixed detection chamber 21;

[0040] The first supply pipe 34 is fixedly disposed at the input end of the output head 31 and is connected to the output head 31.

[0041] The first linear driver 33 is fixedly mounted vertically on the frame 1 and its output shaft passes through the frame 1 and is fixedly connected to the push plate 32.

[0042] When it is necessary to push the detection medium towards the gas diffusion layer 11, the external steam generator is first started, so that steam is continuously and stably output into the first supply pipe 34. The steam is guided into the output head 31 through the first supply pipe 34 and finally delivered into the fixed detection chamber 21, so that the interior of the fixed detection chamber 21 is completely filled with high-humidity steam in a short period of time. As the steam pressure continues to rise, the steam will spontaneously penetrate through the gas diffusion layer 11 towards the moving detection chamber 22 and react with the reaction medium on the upper surface of the gas diffusion layer 11.

[0043] To further ensure the stability and uniformity of steam distribution within the detection chamber, the first linear actuator 33 is driven to continuously compress and push the steam from bottom to top using the pusher plate 32. This applies additional pressure to the steam, allowing it to penetrate the microporous structure of the diffusion layer under constant and controllable driving conditions. The pushing pressure can be adjusted according to the different thicknesses, densities, and porosities of the gas diffusion layer 11 to ensure consistent detection results for different materials under the same reference pressure conditions, thereby further improving detection sensitivity and data comparability.

[0044] Through the dual drive of "steam filling + push plate 32 pressurization", steam can penetrate the diffusion layer with higher stability and uniformity, significantly improving the consistency, controllability and overall accuracy of air permeability testing.

[0045] When it is necessary to deliver the reaction medium to the surface of the gas diffusion layer 11, simply activate the first export unit 41 to guide the reaction medium from the direction of the active detection chamber 22 and evenly spread it onto the surface of the gas diffusion layer 11, forming a reaction layer of uniform thickness and complete coverage. After the reaction medium is sprayed, immediately remove the isolation plate 42 to allow the detection module 5 to obtain an unobstructed observation view, and activate the detection medium output module 3 and the detection module 5 to work together to complete the real-time recording and analysis of the color development or wetting changes of the reaction medium, thereby realizing the real-time detection of the permeability of the gas diffusion layer 11.

[0046] Furthermore, when it is necessary to improve the accuracy and uniformity of the reaction medium spreading, the second export unit 43 can be driven to further distribute the reaction medium along the longitudinal channel, making its coverage more uniform and ensuring that each area of ​​the diffusion layer is in the same initial detection state, thereby avoiding detection deviations caused by uneven medium distribution.

[0047] Through the cooperation of the first export unit 41 and the second export unit 43, it can be ensured that the reaction medium forms a uniform and stable coating layer on the surface of the diffusion layer, effectively improving the consistency of the reaction manifestation and enhancing the objectivity and accuracy of the air permeability test results.

[0048] When a more uniform distribution of the reaction medium to the upper surface of the gas diffusion layer 11 is required, the isolation plate 42 is first fully inserted into the movable detection chamber 22 to temporarily shield the diffusion layer. Then, an external power source is connected to drive two vibrators 432 to operate synchronously. When the vibrators 432 are working, they cause the sieve plate 431 to vibrate at a low amplitude and high frequency, causing the reaction medium within the sieve plate 431 to quickly disperse and distribute evenly. Through the vibrating sieve structure, the reaction medium can be evenly sprinkled as fine powder particles onto the surface of the gas diffusion layer 11, achieving highly consistent initial detection conditions.

[0049] The use of a vibrating screen structure can significantly improve the uniformity of reaction medium distribution, reduce medium accumulation, blank areas or agglomeration, and further improve the uniformity and stability of air permeability test results.

[0050] See Figure 8 As shown: The first export unit 41 is provided with a spray head 411 that can export the reaction medium toward the active detection chamber 22 and a second supply pipe 412 that can introduce the reaction medium into the spray head 411.

[0051] When it is necessary to introduce the reaction medium into the active detection chamber 22, the second supply pipe 412 is connected to the external reaction medium supply equipment, so that the reaction medium is transported to the inside of the spray head 411 through the second supply pipe 412. The spray head 411 sprays the reaction medium evenly on the upper surface of the gas diffusion layer 11 through its porous spray structure, so that the coverage area is spread in a large range and uniformly, thereby meeting the requirements of high-precision air permeability testing for the consistency of the initial spray layer.

[0052] See Figure 2 As shown: The limiting observation module 2 also includes a fixed frame 24 and a second linear actuator 23 capable of driving the movable detection chamber 22 longitudinally away from or close to the fixed detection chamber 21; there are two second linear actuators 23, which are vertically arranged opposite each other on both sides of the frame 1 through the fixed frame 24 and the driving end passes through the fixed frame 24 and is fixedly connected to the movable detection chamber 22.

[0053] When the gas diffusion layer 11 needs to be quickly clamped, an external power supply is connected to drive the second linear actuator 23 to extend its output shaft and drive the movable detection chamber 22 longitudinally away from the fixed detection chamber 21, forming an opening gap that facilitates placement. The operator then simply places the gas diffusion layer 11 to be tested flat on the upper surface of the movable detection chamber 22, and then drives the second linear actuator 23 again to return the movable detection chamber 22 to its original position, achieving clamping engagement with the fixed detection chamber 21, thereby completing the positioning and clamping operation of the gas diffusion layer 11.

[0054] See Figure 7 As shown: The top two sides of the fixed detection chamber 21 are respectively provided with a first adsorption hole 221 and a second adsorption hole 222 that can adsorb the gas diffusion layer 11.

[0055] Both the first adsorption hole 221 and the second adsorption hole 222 are connected to an external suction device. When the gas diffusion layer 11 needs to be placed into the detection chamber for clamping, in order to eliminate warping, drifting and positioning deviation caused by the thinness of the material, the suction device can be started before placement. The negative pressure is formed through the adsorption holes on both sides of the top of the movable detection chamber 22 to adsorb and stretch the gas diffusion layer 11, so that it is in a stable and flat initial state before entering the clamping position.

[0056] By prepositioning through adsorption, the gas diffusion layer 11 can be effectively kept flat before clamping, reducing wrinkles and positional deviations, and improving the accuracy of air permeability test results from the source.

[0057] See Figure 6 As shown: The detection module 5 further includes a guide rod 52 that can horizontally guide the detection head 51 to adjust the detection position and a supplementary light 53 that can provide supplementary lighting to the detection area when the detection head 51 detects the gas diffusion layer 11; the guide rod 52 is horizontally fixedly installed in the movable detection chamber 22 and is located near the top of the movable detection chamber 22; the detection head 51 is vertically slidably installed on the guide rod 52; there are two supplementary lights 53, which are fixedly installed relative to each other in the movable detection chamber 22.

[0058] The detection head 51 is specifically a CCD detection camera.

[0059] When a comprehensive test of the permeability of the gas diffusion layer 11 is required, the detection head 51 continuously records the color development or wetting changes of the surface reaction medium. This allows for point-by-point and surface-by-surface testing of the permeability behavior in each area within the diffusion layer, achieving real-time monitoring with no blind spots or missed detections. During the testing process, the supplementary light 53 provides stable illumination, effectively improving the imaging quality of the reaction area. This enables the detection head 51 to obtain a high-contrast, low-noise test image, improving the accuracy of image recognition and data analysis.

[0060] The detection head 51 and the supplementary light 53 work together to achieve high-precision, full-area recording of changes in the diffusion layer reaction, ensuring that the detection process is not affected by changes in ambient light and improving the overall reliability of the detection.

[0061] Furthermore, a defogging module is circumferentially arranged outside the detection end of the CCD inspection camera, which can continuously circumferentially absorb or locally heat the detection end of the CCD inspection camera, thereby ensuring that the detection end of the CCD inspection camera is always in a high-definition recording state and will not be affected by the steam in the active detection chamber 22; the defogging module is existing technology and will not be described in detail here, its purpose is to continuously remove steam from the detection end of the CCD inspection camera.

[0062] This invention not only enables efficient clamping of the gas diffusion layer but also allows for comprehensive and high-precision detection of the gas diffusion layer without blind spots.

[0063] The above embodiments only illustrate one or more implementations of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the appended claims.

Claims

1. A gas permeability detection device for a gas diffusion layer of a hydrogen fuel cell, characterized by, The utility model relates to a kind of gas permeability testing device, including: Rack; Limit observation module, horizontally fixedly arranged on the rack, for clamping gas diffusion layer to be measured, it includes a fixed detection bin under gas diffusion layer and an openable and closable active detection bin on gas diffusion layer; Detection medium output module, arranged at the bottom of the fixed detection bin, for outputting detection medium into the fixed detection bin; Reaction medium output module, arranged in the active detection bin, for outputting reaction medium capable of developing color reaction with the detection medium into the active detection bin; Detection module, arranged in the active detection bin, with detection end vertically facing the upper surface of the gas diffusion layer; Wherein, during detection, the detection medium penetrates the gas diffusion layer under pressure driving, enters the active detection bin and develops color reaction with the reaction medium, and the detection module evaluates the gas permeability of the gas diffusion layer by capturing the change of color development area; The detection medium output module further includes a first linear driver capable of driving the push plate to longitudinally slide in the fixed detection bin and a first supply pipe capable of supplying detection medium into the output head in real time; The reaction medium output module further includes an isolation plate capable of isolating the detection module when introducing reaction medium into the active detection bin and a second discharge unit fixedly arranged at the bottom of the isolation plate and capable of introducing reaction medium into the active detection bin; The isolation plate is slidingly plugged into the middle of the active detection bin; The second discharge unit is provided with a sieve plate capable of storing reaction medium and a vibrator capable of actively promoting the sieve plate to vibrate and discharge reaction medium; The sieve plate is horizontally fixedly arranged on the lower surface of the isolation plate; The vibrator is provided with two, and the two vibrators are oppositely fixedly arranged on the two sides of the lower surface of the isolation plate.

2. The gas permeability detection apparatus for a gas diffusion layer of a hydrogen fuel cell according to claim 1, wherein The first discharge unit is provided with a spray head capable of discharging reaction medium into the active detection bin and a second supply pipe capable of introducing reaction medium into the spray head.

3. The gas permeability detection apparatus for a gas diffusion layer of a hydrogen fuel cell according to claim 1, wherein The limit observation module further includes a fixed frame and a second linear driver capable of driving the active detection bin to longitudinally move away from or close to the fixed detection bin; The second linear driver is provided with two, and the two second linear drivers are oppositely arranged on the two sides of the rack in vertical state and fixedly connected with the active detection bin through the fixed frame.

4. The apparatus according to claim 1, wherein The top of the fixed detection bin is further provided with a first adsorption hole and a second adsorption hole capable of adsorbing gas diffusion layer on both sides.

5. The apparatus according to claim 1, wherein The detection module further includes a guide rod capable of horizontally guiding the detection head to adjust the detection position and a fill light capable of filling light to the detection area when the detection head detects the gas diffusion layer; The guide rod is horizontally fixedly arranged in the active detection bin and close to the top of the active detection bin; The detection head is slidingly arranged on the guide rod in vertical state; The fill light is provided with two, and the two fill lights are oppositely fixedly arranged in the active detection bin.

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