Repair method for edge bubble and glue shortage defects of photovoltaic module

Abstract

The invention relates to a photovoltaic module edge bubble and glue shortage defect repairing method, and belongs to the technical field of photovoltaic module packaging, the repairing method comprises the following steps: heating a glue film until the glue film is molten; when the defect type is a bubble at the edge of the photovoltaic module, heating the defect position and stripping the adhesive film at the defect position, placing the molten adhesive film at the defect position, and then pressurizing and cooling to finish repairing; and when the defect type is that the edge of the photovoltaic module is lack of glue, placing the molten glue film at the defect position, and then pressurizing and cooling to finish repairing. According to the invention, a feasible and easy-to-operate reworking and repairing means is provided for most c-grade or unqualified products caused by photovoltaic module edge bubbles and edge glue shortage in the photovoltaic production process, the cost loss and waste of photovoltaic production are reduced to a certain extent, and the production yield of the same batch of products is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of photovoltaic module packaging, and in particular relates to a method for repairing bubbles and adhesive deficiency defects at the edge of a photovoltaic module. Background Art

[0002] Solar photovoltaic modules are the core and most important part of solar power generation systems. Their function is to convert solar energy into electrical energy, or to store it in batteries, or to drive loads. The service life of photovoltaic module products is at least 25 years. It is necessary to ensure its environmental tolerance and certain mechanical properties. Photovoltaic modules mainly include nine core components such as battery cells, interconnection bars, bus bars, front panels, EVA, back panels, frames, silicone, and junction boxes. The preparation of photovoltaic modules mainly includes two steps: battery cell interconnection and lamination. Lamination is the key to obtaining the basic structure of photovoltaic modules. Generally, it is a five-layer structure of front panel / film / battery cell / film / back panel formed by high-temperature lamination and vacuum packaging in a laminator. After lamination and cooling, the photovoltaic laminate obtained is protected by aluminum frames and silicone sealing edges to prevent corrosion of battery electrodes and interconnections and battery breakage. The general lamination stacking sequence is as follows: Figure 1 As shown, it is composed of a back panel, an adhesive film, a solar cell sheet, an adhesive film, and a front panel.

[0003] For laminated parts with edge bubbles and lack of glue, the existing repair method is to laminate the defective components again. However, this method is mostly used for large-area bubbles and large-area lack of glue in components caused by abnormal lamination parameters of equipment. The repair effect is small, time-consuming and raw material costs are high, and there is a risk of component cracking and bubble enlargement after lamination again. There is no rework and repair method for such defective components for the time being, and they are basically treated as C-level or unqualified, or even scrapped, which will lead to adverse consequences such as reduced product production yield and increased production costs. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a method for repairing bubbles and glue deficiency defects on the edges of photovoltaic modules. The method is suitable for repairing bubbles and glue deficiency on the edges of photovoltaic modules caused by abnormalities such as film laying offset, equipment operation abnormalities, and insufficient vacuum pumping capacity. The method can reduce the cost waste caused by defective and scrapped photovoltaic modules and improve the product qualification rate to a certain extent.

[0005] The present invention is specifically implemented through the following technical solutions:

[0006] A method for repairing edge bubbles and edge glue deficiency defects of a photovoltaic module comprises the following steps:

[0007] Heating the film until it melts;

[0008] When the defect type is a bubble at the edge of the photovoltaic module, the defect position is heated and the adhesive film at the defect position is peeled off, and then the molten adhesive film is placed at the defect position, and then pressurized and cooled to complete the repair;

[0009] When the defect type is glue deficiency at the edge of the photovoltaic module, the defect location is heated, the molten adhesive film is placed at the defect location, and then pressurized and cooled to complete the repair.

[0010] Among them, the photovoltaic module structure includes a backplane, a first layer of film, a battery cell, a second layer of film, and a front plane stacked in sequence; the size of the backplane is equal to the size of the front plane; the sizes of the first layer of film and the second layer of film are equal and equal to the size of the backplane; the overall layout size of the battery cell is smaller than the size of the backplane.

[0011] Furthermore, the adhesive film is heated until it melts, and the adhesive film used is consistent with the adhesive film constituting the photovoltaic module; the adhesive film is selected from any one of polyethylene-polyvinyl acetate copolymer (EVA), polyolefin elastomer (POE), polyvinyl butyral (PVB), and co-extruded POE adhesive film (EPE).

[0012] Furthermore, the heating temperature of the heating defect position is 120-150°C;

[0013] Preferably, the heating temperature of the heating defect position is 120-135°C;

[0014] Furthermore, the heating method for heating the defective position is hot air heating or infrared heating.

[0015] Furthermore, the heating size range of the heating defect position is larger than the size range of the defect position.

[0016] Considering that the core material of the backplane of single-glass photovoltaic modules is mostly polyethylene terephthalate (PET), or the front and backplane of flexible modules are at risk of high-temperature deformation, and preventing various situations such as breakage of the front glass of single-glass modules and the front and back glass of double-glass modules caused by sudden temperature changes, it is important to set the appropriate heating temperature and heating range.

[0017] Furthermore, placing the molten adhesive film at the defective position includes: taking a spare molten adhesive film and slowly injecting it along the boundary between the defective position and the normal adhesive film until the molten adhesive film fills the defective position.

[0018] Optionally, when the defect type is a bubble at the edge of a photovoltaic module, a molten adhesive film is placed at the bubble defect position, including: taking a spare molten adhesive film and slowly injecting it along the junction between the bubble defect position after the adhesive film is peeled off and the normal adhesive film that has not been peeled off until the molten adhesive film fills the bubble defect position after the adhesive film is peeled off.

[0019] Optionally, when the defect type is glue deficiency at the edge of the photovoltaic module, a molten adhesive film is placed at the glue deficiency defect position, including: taking a spare molten adhesive film and slowly injecting it along the junction between the glue deficiency defect position and the normal adhesive film until the molten adhesive film fills the glue deficiency defect position.

[0020] Optionally, use a heat-resistant glass syringe, a heat-resistant straw or other tools to take out the spare molten adhesive film.

[0021] The purpose of slowly injecting the molten glue is to control the injection volume and the uniform distribution of the glue volume, while preventing bubbles from being generated due to too fast injection or overflow due to too little or too much glue volume.

[0022] Furthermore, the pressurization satisfies the following conditions: (1) the area to which the pressure is applied is larger than the area of ​​the defect location; and (2) the pressurization time is not less than 10 minutes.

[0023] Furthermore, the cooling satisfies the following conditions: (1) the cooling temperature is room temperature; and (2) the cooling time is not less than 20 minutes.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention provides a feasible and easy-to-operate rework and repair method for most C-level or unqualified products caused by bubbles and lack of glue on the edges of photovoltaic modules during the photovoltaic production process, which reduces the cost and waste of photovoltaic production to a certain extent and improves the production yield of the same batch of products.

[0026] Other features and advantages of the present invention will be described in the following description, and partly become obvious from the description, or be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the specific embodiments pointed out in the description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The lamination sequence of conventional photovoltaic modules;

[0028] Figure 2 A flow chart of the repair method provided by the present invention;

[0029] Figure 3 Schematic diagram of defective parts of photovoltaic modules;

[0030] Figure 4 A schematic diagram of the heating bubble defect position in Example 1;

[0031] Figure 5 This is a schematic diagram of injecting a molten adhesive film into a bubble defect position in Example 1;

[0032] Figure 6 Schematic diagram of pressurizing the defect location. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the present invention clearer, the implementation scheme of the present application will be described in detail below in conjunction with specific examples. The technical terms and scientific terms used in the present invention have the meanings generally understood by those of ordinary skill in the art to which the present invention belongs, without other definitions. Without departing from the concept of the present invention, those skilled in the art may make various improvements and changes to the specific implementation methods of the present invention specification, which all belong to the protection scope of the present invention. The raw materials used in the present invention are all commercially available unless otherwise specified.

[0034] Example 1

[0035] A method for repairing bubbles and adhesive deficiency defects on the edge of a photovoltaic module comprises the following steps:

[0036] (1) Determine the defect location of the PV module and determine whether it meets the repair conditions;

[0037] (2) heating the film until it is melted and set aside;

[0038] (3) Select PV panels that meet the repair conditions, determine the defect type, and then perform the corresponding repairs.

[0039] Determining the defect position of the photovoltaic module and determining whether it meets the repair conditions includes: first determining that the defect position of the photovoltaic module is at the edge of the photovoltaic module, and then determining whether it meets the repair conditions; meeting the repair conditions means: when the defect is bubbles or glue deficiency generated at the edge of the photovoltaic module, it is determined that the repair conditions are met, Figure 2 This is a flow chart of the repair method provided by the present invention.

[0040] Specifically, the repair method is:

[0041] (1) Determine the defect location of the PV module and determine whether it meets the repair conditions;

[0042] Get the C-level photovoltaic modules in a batch of photovoltaic production tasks.

[0043] The structure of this batch of photovoltaic modules is: tempered glass front panel / EVA film / cell / EVA film / tempered glass back panel; among which, the size of the tempered glass front panel and tempered glass back panel before lamination is equal to the size of the photovoltaic modules.

[0044] The PV modules that meet the repair conditions (when the defect is bubbles or glue deficiency at the edge of the PV module) are selected as the samples to be repaired. The defective parts of the samples to be repaired can be found in Figure 3 The schematic diagram of defective parts of photovoltaic modules shows bubble defects and adhesive deficiency defects.

[0045] (2) Heat the EVA film at 150°C until it melts, and keep it at a temperature above 120°C for later use.

[0046] (3) The defect type is determined to be a bubble at the edge of the photovoltaic module. The bubble defect is located in the film layer between the tempered glass front plate and the battery cell. The bubble defect position of the tempered glass front plate is locally heated with hot air at 120°C. The heating range is larger than the bubble defect position. After the film at the defect position is melted, the film at the defect position is peeled off by scraping. Then, the spare molten EVA film is sucked with a heat-resistant glass syringe and slowly injected along the junction between the defect position after the film is peeled off and the unpeeled film until the molten film fills the bubble defect position after the film is peeled off. During the process, care must be taken to ensure that no new bubbles are generated. This process can be seen in Figure 4 Schematic diagram of the heating bubble defect location and Figure 5 Schematic diagram of injecting molten adhesive film into the position of the bubble defect. Then use a G-shaped clamp with a contact area larger than the injection area of ​​the component to pressurize for 10 minutes to keep the repair position and the normal position of the component at the same height, remove the molten adhesive film squeezed out during pressurization, and finally cool to room temperature. After 1 hour, the repaired photovoltaic component is obtained. Among them, Figure 6 This is a schematic diagram of pressurizing the defective location, using a G-shaped clamp for local pressurization.

[0047] Example 2

[0048] The difference from Example 1 is that (3) the defect type is determined to be glue deficiency at the edge of the photovoltaic module. The glue deficiency defect is located in the glue film layer between the tempered glass front plate and the battery cell and the glue film layer between the tempered glass back plate and the battery cell. The glue deficiency defect position of the tempered glass back plate is locally heated by hot air at 120°C. The heating range is larger than the glue deficiency defect position, so that the normal glue film at the glue deficiency boundary melts to facilitate fusion with the subsequent filling glue film. The spare molten EVA glue film is sucked with a heat-resistant glass syringe and slowly injected along the junction between the glue deficiency position and the normal glue film until the molten glue film fills the glue deficiency defect position. During the process, it is necessary to ensure that the amount of glue is sufficient and no new bubbles are generated. Then, a G-shaped clamp with a contact area larger than the injection area of ​​the component is used to pressurize for 15 minutes to keep the repair position and the normal position of the component in the same height. The molten glue film squeezed out during pressurization is removed, and finally cooled to room temperature. After 1 hour, a repaired photovoltaic module is obtained.

[0049] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for repairing edge bubbles and edge glue defects of photovoltaic modules, characterized in that: The following steps are involved: Heating the film until it melts; When the defect type is a bubble at the edge of the photovoltaic module, the defect position is heated and the adhesive film at the defect position is peeled off, and then the molten adhesive film is placed at the defect position, and then pressurized and cooled to complete the repair; When the defect type is glue deficiency at the edge of the photovoltaic module, the defect location is heated, the molten adhesive film is placed at the defect location, and then pressurized and cooled to complete the repair.

2. The repair method according to claim 1, characterized in that: The adhesive film used in the step of heating the adhesive film until it melts is consistent with the adhesive film constituting the photovoltaic module.

3. The repair method according to claim 1, characterized in that: The heating temperature of the heating defect position is 120-150°C.

4. The repair method according to claim 1, characterized in that: The heating size range of the heating defect position is larger than the size range of the defect position.

5. The repair method according to claim 1, characterized in that: The heating method for heating the defective position is hot air heating or infrared heating.

6. The repair method according to claim 1, characterized in that: Placing the molten adhesive film at the defective position includes: taking a spare molten adhesive film and slowly injecting it along the boundary between the defective position and the normal adhesive film until the molten adhesive film fills the defective position.

7. The repair method according to claim 1, characterized in that: In the pressurization, the area where the pressure is applied is larger than the area of ​​the defect position.

8. The repair method according to claim 7, characterized in that: The pressurization time is not less than 10 minutes.

9. The repair method according to claim 1, characterized in that: The cooling time of the cooling is not less than 20 minutes.

10. The repair method according to claim 1, characterized in that: The cooling temperature of the cooling is room temperature.

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