Device for testing the ultraviolet light degradation of photovoltaic cells

Abstract

This application relates to an apparatus for testing the ultraviolet (UV) light decay of photovoltaic (PV) cells. The apparatus includes a housing with an internal testing space, a first mounting platform laterally positioned within the testing space to support the bare PV cell to be tested, and a conductive element within the testing space. The two ends of the conductive element are connected to a first electrode and a second electrode of opposite polarity on the bare PV cell, respectively, to short-circuit the PV cell. During testing, a hot carrier cycling effect is formed within the bare PV cell, and the electron-hole kinetic energy excited by UV photons can reach several eV. Some electrons cross the SiNx / Si interface barrier and directly bombard the passivation layer structure, inducing a cascade effect of material damage, thereby improving the accuracy of the test results. Furthermore, since the bare PV cell is tested directly, there is no need to laminate the bare PV cell and glass to form a PV cell, shortening the time required to complete one test and thus improving testing efficiency.

Description

Technical Field

[0001] This application relates to the technical field of photovoltaic cells, and in particular to an apparatus for testing the ultraviolet light decay of photovoltaic cells. Background Technology

[0002] High-efficiency photovoltaic cells (such as TOPCON, HJT, and BC cells) will experience a certain degree of power reduction after being exposed to ultraviolet light for a certain period of time due to light-induced degradation caused by ultraviolet light. Therefore, it is necessary to test the ultraviolet light degradation of the cells before large-scale production.

[0003] Currently, there are two main methods for UV testing:

[0004] One method involves directly placing the bare solar cell under a UV chamber for 30 kWh and then evaluating the efficiency degradation or on-state voltage degradation of the cell. However, the degradation results measured by this method do not have a clear correlation with the actual light-induced degradation results of the module.

[0005] Method two involves fabricating bare solar cells into solar modules and subjecting them to prolonged UV irradiation, either indoors or outdoors, with the positive and negative terminals short-circuited. While method two effectively characterizes the UV resistance of solar modules under UV irradiation, it cannot directly test the electrical performance of the solar cells. Losses during module fabrication, such as encapsulation and photo-soldering, are also factored into the power degradation caused by UV light, leading to an overestimation of the actual light degradation and affecting the accuracy of the test. Furthermore, the fabrication cycle plus UV degradation time in method two requires 20 days to obtain results, making the test time-consuming. Additionally, because the light degradation rack supporting the solar modules can only be laid flat at the same level in the light-induced degradation experimental device, the number of solar modules that can be accommodated in the device is limited by its size and floor space. Large-scale light-induced degradation experiments need to be conducted in multiple batches, resulting in low testing efficiency. Utility Model Content

[0006] Therefore, it is necessary to provide a device for testing the ultraviolet light decay of photovoltaic cells to improve the accuracy and efficiency of photovoltaic cell testing.

[0007] An apparatus for testing the ultraviolet light degradation of a photovoltaic cell, the photovoltaic cell comprising a bare cell, wherein a first electrode and a second electrode of opposite polarity are disposed on the bare cell; the apparatus comprises:

[0008] The enclosure contains a testing space.

[0009] The first mounting platform is horizontally positioned within the testing space to support the bare battery cell to be tested;

[0010] A conductive element is disposed within the detection space, with its two ends connected to the first electrode and the second electrode, respectively, so that the bare battery cell is in a short-circuit state.

[0011] In one embodiment, the device further includes a colorless and transparent box body movably disposed within the detection space, the box body having a receiving cavity, and the first placement stage disposed within the receiving cavity.

[0012] In one embodiment, the first mounting platform is slidably constrained on the corresponding side wall of the accommodating cavity along a first direction, the first direction being at an angle to the height direction of the box body, and the box body is provided with an entrance / exit for the first mounting platform to enter and exit the accommodating cavity along the first direction.

[0013] In one embodiment, the accommodating cavity is provided with guide rails extending along the first direction on both opposite side walls, and a slider is provided on the first mounting platform, the slider slidingly engaging with the guide rails.

[0014] In one embodiment, the photovoltaic cell further includes a first glass and a second glass arranged side by side with the bare cell. The device further includes a second mounting platform for supporting the first glass and a third mounting platform for supporting the second glass. The second mounting platform and the third mounting platform are both arranged laterally in the receiving cavity and along the height direction of the box body, with the first mounting platform located between the second mounting platform and the third mounting platform.

[0015] In one embodiment, the distance between the first mounting platform and the second mounting platform in the height direction of the box body is 2.5 cm to 7.5 cm; and / or, the distance between the first mounting platform and the third mounting platform is 2.5 cm to 7.5 cm.

[0016] In one embodiment, both the second and third mounting platforms are slidably constrained on the sidewall of the accommodating cavity along the first direction, and both enter and exit the accommodating cavity through the inlet / outlet.

[0017] In one embodiment, the first mounting platform is provided with a first groove for receiving the bare battery sheet, the second mounting platform is provided with a second groove for receiving the first glass, and the third mounting platform is provided with a third groove for receiving the second glass.

[0018] In one embodiment, a light source is provided on the top of the housing to illuminate the bare battery cell, thereby generating photogenerated carriers on the surface of the bare battery cell.

[0019] In one embodiment, a reflective layer is affixed to the inner wall of the housing to reflect the light emitted by the light source onto the bare battery cell.

[0020] Compared with existing technologies, the device for testing the UV degradation of photovoltaic cells provided in this application connects the first and second electrodes of the bare cell under test through a conductive component during UV degradation testing, thus putting the bare cell in a short-circuit state. This creates a hot carrier cycling effect within the bare cell, and the electron-hole kinetic energy excited by ultraviolet photons can reach several eV. Some electrons cross the SiNx / Si interface barrier and directly bombard the passivation layer structure, triggering a cascade effect of material damage, thereby improving the accuracy of the test results. Furthermore, since the device in this application can directly test the bare cell without laminating the bare cell and glass into a photovoltaic cell, it not only avoids the interference of encapsulation losses and photowelding losses during module manufacturing on the degradation test results of the bare cell, improving the accuracy of the test results, but also, since the bare cell only needs to be irradiated with 30 kWh, the device in this application completes one test in a short time, thereby improving the testing efficiency. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of an apparatus for testing the ultraviolet light decay of photovoltaic cells in one embodiment of this application;

[0023] Figure 2 This is a schematic diagram of the structure of the box in one embodiment of this application.

[0024] Reference numerals: 1. Photovoltaic cell; 110. Bare cell; 111. First electrode; 112. Second electrode; 120. First glass; 130. Second glass; 2. Device for testing the ultraviolet light decay of photovoltaic cells; 210. Box; 2101. Detection space; 220. Housing; 2201. Receptacle; 221. First mounting platform; 2211. Guide rail; 2212. Slider; 2213. First groove; 222. Second mounting platform; 2221. Second groove; 223. Third mounting platform; 2231. Third groove; 230. Conductive component; 240. Light source. Detailed Implementation

[0025] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0026] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0028] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0029] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0030] To ensure the quality of photovoltaic cell 1, it is necessary to test the degradation of photovoltaic cell 1. The photovoltaic cell 1 to be tested includes a bare cell 110, on which a first electrode 111 and a second electrode 112 with opposite polarities are disposed.

[0031] Please see Figures 1 to 2 This application provides a device 2 for testing the ultraviolet light decay of photovoltaic cells. The device 2 includes a box 210 with an internal detection space 2101, a first mounting platform 221 horizontally disposed in the detection space 2101 to support the bare cell 110 to be tested, and a conductive element 230 is also disposed in the detection space 2101. The two ends of the conductive element 230 are respectively connected to a first electrode 111 and a second electrode 112 to put the bare cell 110 in a short-circuit state.

[0032] It is understandable that when the test device 2 in this embodiment is used to perform light attenuation test on the bare cell 110 of the photovoltaic cell 1 under test, the bare cell 110 is in a short-circuit state because the first electrode 111 and the second electrode 112 of the bare cell 110 are connected by the conductive component 230. As a result, a hot carrier cycling effect will be formed in the bare cell 110, and the electron-hole kinetic energy excited by ultraviolet photons can reach several eV. Some electrons cross the SiNx / Si interface barrier and directly bombard the passivation layer structure, causing a cascade effect of material damage, thereby improving the accuracy of the test results. Furthermore, since the device 2 in this embodiment can directly test the bare solar cell 110 without laminating the bare solar cell 110 and glass into a photovoltaic cell 1, it not only avoids the interference of degradation caused by encapsulation loss, photowelding loss and other factors during the module manufacturing process on the degradation test results of the bare solar cell 110, thus improving the accuracy of the test results, but also, since the bare solar cell 110 only needs to be irradiated with 30 kWh, the device 2 in this embodiment takes less time to complete one test, thereby improving the detection efficiency.

[0033] It should be noted that the conductive component 230 only needs to be connected to the first electrode 111 and the second electrode 112 of the bare battery cell 110 during testing. Schematic illustration shows the conductive component as a clamp. When testing of the bare battery cell 110 is not required, the conductive component 230 can be stored in the housing 210. Schematic illustration shows a storage box on the side wall of the housing 210 for storing the conductive component 230, thus preventing its loss.

[0034] In one embodiment, the device 2 further includes a colorless and transparent housing 220, which is movably disposed within the detection space 2101. See also... Figure 2The housing 220 has a receiving cavity 2201, and the first mounting stage 221 is located within the receiving cavity 2201. The bare battery cell 110 is placed within the movable housing 220, making it easier to move the bare battery cell 110 to be tested within the testing space 2101 and facilitating the arrangement of the bare battery cell 110 within the housing 210. Furthermore, multiple housings 220 can be arranged within the housing 210, and these housings 220 can be arranged in the most compact manner, that is, arranging as many bare battery cells 110 to be tested as possible within the housing 210. This allows for the simultaneous irradiation of multiple bare battery cells 110 to be tested, thereby improving the testing efficiency of the bare battery cell 110.

[0035] Furthermore, the housing 220 has colorless and transparent sidewalls and a colorless and transparent top wall fixed to the top of the sidewalls for sealing the sidewalls. The sidewalls and top wall enclose the accommodating cavity 2201. In this way, the light beam irradiated on the bare cell 110 will not be affected by the housing 220, ensuring that the bare cell 110 is irradiated by light, thereby enabling the bare cell 110 to undergo hot carrier cycling effect and light attenuation.

[0036] As an illustration, the sidewalls can be made of acrylic, high-transparency glass, etc. This application does not limit this, as long as they are colorless and transparent.

[0037] In one embodiment, the first mounting platform 221 is slidably constrained to the corresponding side wall of the receiving cavity 2201 along a first direction X. The first direction X forms an angle with the height direction Y of the housing 220. The housing 220 is provided with an inlet / outlet for the first mounting platform 221 to enter and exit the receiving cavity 2201 along the first direction X. It is understood that when the bare battery cell 110 to be tested needs to be placed into the housing 220, the first mounting platform 221 can be moved out of the receiving cavity 2201 from the inlet / outlet first, the bare battery cell 110 to be tested can be placed on the first mounting platform 221, and then the first mounting platform 221 can be moved back into the receiving cavity 2201 from the inlet / outlet. This makes it easier to place or remove the bare battery cell 110 to be tested from the receiving cavity 2201.

[0038] Furthermore, the accommodating cavity 2201 is provided with guide rails 2211 extending along the first direction X on both opposite side walls, and a slider 2212 is provided on the first mounting platform 221, with the slider 2212 slidingly engaging with the guide rails 2211. In this way, the bare battery cell 110 can be pushed into or pulled out of the accommodating cavity 2201 by pushing or pulling, thereby further simplifying the method of placing or removing the bare battery cell 110 from the accommodating cavity 2201.

[0039] In one embodiment, the photovoltaic cell 1 further includes a first glass 120 and a second glass 130, both arranged side-by-side with the bare cell 110. See also... Figure 2 The device 2 also includes a second mounting platform 222 for supporting the first glass 120 and a third mounting platform 223 for supporting the second glass 130. Both the second mounting platform 222 and the third mounting platform 223 are arranged laterally within the accommodating cavity 2201, and along the height direction Y of the housing 220, the first mounting platform 221 is located between the second mounting platform 222 and the third mounting platform 223. It is understood that actual photovoltaic modules are laminated from bare solar cells 110 and other components (such as EVA film, front glass on the front of the bare solar cell 110, back glass on the back of the bare solar cell 110, etc.). In this embodiment, when testing the photovoltaic cell 1, the front glass can be placed on the second mounting platform 222 and the back glass on the third mounting platform 223. Therefore, the sequentially arranged front glass, bare solar cell 110, and back glass can simulate the lamination state of a photovoltaic module, thereby making the light attenuation test results more accurate.

[0040] Schematic, the EVA film and the front glass can also be placed together on the second mounting platform 222 to more accurately simulate the laminated photovoltaic module. In other embodiments, the device 2 further includes a fourth mounting platform for supporting the EVA film, and the fourth mounting platform is disposed between the first mounting platform 221 and the second mounting platform 222 along the height direction Y of the housing 220.

[0041] In one embodiment, the distance between the first mounting platform 221 and the second mounting platform 222 in the height direction Y of the housing 220 is 2.5 cm to 7.5 cm. This ensures that the distance between the first mounting platform 221 and the second mounting platform 222 is not too close, which would make it inconvenient to place and remove the bare solar cell 110 in the first mounting platform 221, nor would the distance between the first mounting platform 221 and the second mounting platform 222 be too far, preventing the first glass 120 and the bare solar cell 110 from failing to function as a simulated laminated photovoltaic cell 1.

[0042] In one embodiment, the distance between the first mounting platform 221 and the third mounting platform 223 in the height direction Y of the housing 220 is 2.5 cm to 7.5 cm. This ensures that the distance between the first mounting platform 221 and the third mounting platform 223 is not too close, which would make it inconvenient to place and remove the second glass 130 in the third mounting platform 223, nor would the distance between the first mounting platform 221 and the third mounting platform 223 be too far, preventing the third glass and the bare solar cell 110 from failing to function as a simulated laminated photovoltaic cell 1.

[0043] In one embodiment, the second mounting platform 222 and the third mounting platform 223 are both slidably constrained to the sidewall of the receiving cavity 2201 along the first direction X, and both enter and exit the receiving cavity 2201 through an inlet and outlet. In this way, it is easier to place the first glass 120 and the second glass 130 into or remove them from the receiving cavity 2201.

[0044] See also Figure 2 In one embodiment, the first mounting platform 221 has a first groove 2213 for receiving the bare battery sheet 110, the second mounting platform 222 has a second groove 2221 for receiving the first glass 120, and the third mounting platform 223 has a third groove 2231 for receiving the second glass 130. Thus, the first groove 2213 can limit the position of the bare battery sheet 110, allowing it to be placed more stably on the first mounting platform 221 when the first mounting platform 221 is pushed or pulled to insert or remove the bare battery sheet 110 from the receiving cavity 2201. Similarly, the first glass 120 can be placed more stably on the second mounting platform 222, and the second glass 130 can be placed more stably on the third mounting platform 223.

[0045] See also Figure 1 In one embodiment, a light source 240 is provided on the top of the housing 210. The light source 240 is used to irradiate the bare battery cell 110 to generate photogenerated carriers on the surface of the bare battery cell 110. This allows for continuous irradiation of the surface of the bare battery cell 110 for a long period, and the irradiation time and intensity can be flexibly set. It should be noted that the light source 240 in this embodiment emits ultraviolet light to irradiate the bare battery cell 110 in the device, thereby enabling the testing of the battery cell 110's degradation.

[0046] In one embodiment, a reflective layer is affixed to the inner wall of the housing 210 to reflect the light emitted by the light source 240 to the bare battery cell 110. This improves the utilization rate of the light emitted by the light source 240 and enhances the hot carrier cycling effect on the surface of the bare battery cell 110.

[0047] As an illustration, aluminum foil can be attached to the inner wall of the box to form the aforementioned reflective layer.

[0048] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0049] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. An apparatus for testing the ultraviolet light decay of a photovoltaic cell, the photovoltaic cell (1) comprising a bare cell (110), wherein a first electrode (111) and a second electrode (112) of opposite polarity are disposed on the bare cell (110); characterized in that, The device includes: The housing (210) has an internal detection space (2101). The first mounting platform (221) is horizontally positioned within the testing space (2101) to support the bare battery cell (110) to be tested. A conductive element (230) is disposed in the detection space (2101). The two ends of the conductive element (230) are respectively connected to the first electrode (111) and the second electrode (112) so that the bare battery cell (110) is in a short-circuit state.

2. The apparatus of claim 1, wherein, The device also includes a colorless and transparent box (220), which is movably disposed within the detection space (2101). The box (220) has a receiving cavity (2201) inside, and the first placement platform (221) is disposed within the receiving cavity (2201).

3. The apparatus of claim 2, wherein, The first mounting platform (221) is slidably constrained on the corresponding side wall of the accommodating cavity (2201) along a first direction. The first direction is at an angle to the height direction of the box (220). The box (220) is provided with an entrance and exit for the first mounting platform (221) to enter and exit the accommodating cavity (2201) along the first direction.

4. The apparatus of claim 3, wherein, The accommodating cavity (2201) is provided with guide rails (2211) extending along the first direction on both opposite side walls, and a slider (2212) is provided on the first mounting platform (221), the slider (2212) slidingly engaging with the guide rails (2211).

5. The apparatus of claim 3, wherein, The photovoltaic cell (1) also includes a first glass (120) and a second glass (130) arranged side by side with the bare cell (110). The device also includes a second mounting platform (222) for supporting the first glass (120) and a third mounting platform (223) for supporting the second glass (130). The second mounting platform (222) and the third mounting platform (223) are both arranged laterally in the accommodating cavity (2201), and along the height direction of the box body (220), the first mounting platform (221) is located between the second mounting platform (222) and the third mounting platform (223).

6. The apparatus of claim 5, wherein, In the height direction of the box body (220), the distance between the first mounting platform (221) and the second mounting platform (222) is 2.5 cm to 7.5 cm; and / or, the distance between the first mounting platform (221) and the third mounting platform (223) is 2.5 cm to 7.5 cm.

7. The apparatus of claim 5, wherein, The second mounting platform (222) and the third mounting platform (223) are both slidably constrained on the side wall of the accommodating cavity (2201) along the first direction, and both enter and exit the accommodating cavity (2201) through the inlet and outlet.

8. The apparatus of claim 7, wherein, The first mounting platform (221) is provided with a first groove (2213) for receiving the bare battery sheet (110), the second mounting platform (222) is provided with a second groove (2221) for receiving the first glass (120), and the third mounting platform (223) is provided with a third groove (2231) for receiving the second glass (130).

9. The device of any one of claims 1 to 8, wherein, The top of the housing (210) is provided with a light source (240), which is used to irradiate the bare battery cell (110) so as to generate photogenerated carriers on the surface of the bare battery cell (110).

10. The apparatus of claim 9, wherein, The inner wall of the housing (210) is provided with a reflective layer for reflecting the light emitted by the light source (240) to the bare battery cell (110).

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