Photovoltaic module

Abstract

The utility model relates to a photovoltaic module. The photovoltaic module comprises a first packaging layer, a first adhesive film layer, a battery string layer, a second adhesive film layer and a second packaging layer which are stacked in sequence, the second packaging layer is provided with a first opening, the battery string layer is connected with a bus bar, and the bus bar is led out of the photovoltaic module through the first opening; the photovoltaic module further comprises a first water-blocking layer and a second water-blocking layer, the first water-blocking layer is filled in the first opening of the second packaging layer, and the second water-blocking layer is arranged on at least part of the surface, facing the first water-blocking layer, of the second packaging layer. Wherein the adhesion between the second water-blocking layer and the second packaging layer is better than that between the first water-blocking layer and the second packaging layer, and the water vapor transmittance of the first water-blocking layer is lower than that of the second water-blocking layer.

Description

Technical Field

[0001] This application relates to the field of solar cell technology, and in particular to a photovoltaic module. Background Technology

[0002] Solar cells are highly sensitive to ambient humidity; moisture infiltration can cause significant power degradation. Therefore, effective sealing measures are needed to address potential moisture infiltration pathways. In existing technologies, the backsheet glass requires lead-in holes for the busbars of the cell strings to connect to the junction box. These lead-in holes serve as direct channels between the internal and external environments of the photovoltaic module, posing a risk of moisture infiltration and potentially impacting the long-term reliability of the photovoltaic module. Utility Model Content

[0003] Therefore, it is necessary to provide a photovoltaic module to address the aforementioned technical problems.

[0004] This application provides a photovoltaic module, including a first encapsulation layer, a first encapsulating film layer, a battery string layer, a second encapsulating film layer and a second encapsulation layer stacked in sequence. The second encapsulation layer has a first opening. The battery string layer is connected to a busbar. The busbar extends out to the outside of the photovoltaic module through the first opening.

[0005] The photovoltaic module further includes a first water-blocking layer and a second water-blocking layer, wherein the first water-blocking layer fills a first opening in the second encapsulation layer and the second water-blocking layer is disposed on at least a portion of the surface of the second encapsulation layer facing the first water-blocking layer.

[0006] The adhesion between the second water-blocking layer and the second encapsulation layer is better than that between the first water-blocking layer and the second encapsulation layer, and the water vapor transmission rate of the first water-blocking layer is lower than that of the second water-blocking layer.

[0007] In one embodiment, the first water-blocking layer further extends to cover a first surface of the second encapsulation layer on the side adjacent to the second film layer;

[0008] The second water-blocking layer covers the inner wall of the first opening of the second encapsulation layer, and also covers a portion of the first surface and a portion of the second surface of the second encapsulation layer.

[0009] In one embodiment, the first water-blocking layer further extends to cover a second surface of the second encapsulation layer on the side away from the second film layer;

[0010] The second water-blocking layer covers the inner wall of the first opening of the second encapsulation layer, and also covers a portion of the first surface and a portion of the second surface of the second encapsulation layer.

[0011] In one embodiment, the first water-blocking layer further extends to cover a first surface of the second encapsulation layer on the side near the second adhesive film layer, and a second surface of the second encapsulation layer on the side away from the second adhesive film layer;

[0012] The second water-blocking layer covers the inner wall of the first opening of the second encapsulation layer, and also covers a portion of the first surface and a portion of the second surface of the second encapsulation layer.

[0013] In one embodiment, the material of the first water-blocking layer includes butyl rubber, and the material of the second water-blocking layer includes POE.

[0014] In one embodiment, the basis weight of the POE material in the second water-blocking layer is 100 g / m³. 2 Up to 500g / m 2 .

[0015] In one embodiment, the orthographic projection of the second water-blocking layer onto the second encapsulation layer covers the first opening, and the orthographic projection of the second water-blocking layer onto the second encapsulation layer falls entirely within the orthographic projection of the first water-blocking layer onto the second encapsulation layer.

[0016] In one embodiment, one of the first openings is for the passage of both of the busbars.

[0017] In one embodiment, the diameter of the first opening is 10 mm to 15 mm.

[0018] In one embodiment, the thickness of the first encapsulation layer and / or the second encapsulation layer is 5 mm to 2.5 mm.

[0019] The aforementioned photovoltaic module, by providing a first opening in the second encapsulation layer, facilitates the routing of the busbars of the cell string layer to support the transmission of electrical signals within the cell string layer. For the first opening area, which is susceptible to moisture intrusion, a first water-blocking layer provides excellent water-blocking capability, while a second water-blocking layer enhances the connection reliability between the first water-blocking layer and the second encapsulation layer, preventing detachment due to prolonged humid and hot environments. Therefore, this application provides a photovoltaic module that facilitates cell string encapsulation and offers high water-blocking reliability. Attached Figure Description

[0020] 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.

[0021] Figure 1 This is a schematic diagram of the structure of a photovoltaic module according to one embodiment;

[0022] Figure 2 This is a cross-sectional schematic diagram of a photovoltaic module according to one embodiment;

[0023] Figure 3 This is one of the flowcharts for a method of manufacturing a photovoltaic module according to an embodiment;

[0024] Figure 4 This is a cross-sectional schematic diagram of a photovoltaic module after step S104 in one embodiment;

[0025] Figure 5 This is a second flowchart illustrating a method for preparing a photovoltaic module according to one embodiment;

[0026] Figure 6 This is a cross-sectional schematic diagram of a photovoltaic module after step S206 in one embodiment;

[0027] Figure 7(a) is one of the schematic diagrams of the first water-blocking material layer in one embodiment;

[0028] Figure 7(b) is a second schematic diagram of the first water-blocking material layer in one embodiment;

[0029] Figure 8(a) is one of the schematic diagrams of the second water-blocking material layer in one embodiment;

[0030] Figure 8(b) is a second schematic diagram of the second water-blocking material layer in one embodiment.

[0031] Component designation explanation:

[0032] First encapsulation layer: 110; Second encapsulation layer: 120; First opening: 121; First adhesive film layer: 210; Second adhesive film layer: 220; Battery string layer: 300; Busbar: 310; First water-blocking layer: 410; First water-blocking material layer: 411; Second opening: 412; Second water-blocking layer: 420; Second water-blocking material layer: 421; Third opening: 422. Detailed Implementation

[0033] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0035] It is understood that the terms "first," "second," etc., used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first opening may be referred to as a second opening, and similarly, a second opening may be referred to as a first opening. Both the first opening and the second opening are openings, but they are not the same opening.

[0036] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0037] When used herein, the singular forms of “a,” “an,” and “ / the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0038] This application provides a photovoltaic module. Figure 1 This is a schematic diagram of the structure of a photovoltaic module according to one embodiment, with reference to... Figure 1 The photovoltaic module includes a first encapsulation layer 110, a first encapsulant layer 210, a cell string layer 300, a second encapsulant layer 220, and a second encapsulation layer 120 stacked sequentially.

[0039] The cell string layer 300 is the core structure of the photovoltaic module, comprising multiple solar cells connected by interconnecting strips and busbars 310 to convert incident light energy into electrical energy. The types of solar cells include, but are not limited to, any of the following: TOPCon (Tunnel Oxide Passivating Contacts), HJT (Heterojunction Technology), Interdigitated BackContact (IBC), and perovskite cells.

[0040] The first encapsulation layer 110 and the second encapsulation layer 120 can be glass, including but not limited to tempered glass. Specifically, the thickness of the first encapsulation layer 110 and / or the second encapsulation layer 120 is 1.5 mm to 2.5 mm. For example, the thickness of the first encapsulation layer 110 is 1.5 mm, 2 mm, or 2.5 mm, and the thickness of the second encapsulation layer 120 is 1.5 mm, 2 mm, or 2.5 mm. The first encapsulation layer 110 and the second encapsulation layer 120 are used to provide physical protection for the internal cell string layer 300, preventing external environmental factors (such as rain and sandstorms) from corroding the internal cells. The second encapsulation layer 120 has a first opening 121, the shape of which includes but is not limited to any one of a circle, a square, or a rectangle. When the shape of the first opening 121 is circular, the diameter of the first opening 121 is 10 mm to 15 mm. For example, the diameter of the first opening 121 is 10 mm, 12 mm, or 15 mm. The busbar 310 extends to the outside of the photovoltaic module through the first opening 121. Specifically, the busbar 310 can be connected to an external junction box, busbar 310 or other components to simplify the installation and maintenance of photovoltaic modules.

[0041] The first adhesive layer 210 and the second adhesive layer 220 serve as bonding materials. The first adhesive layer 210 is used to bond the battery string layer 300 to the first encapsulation layer 110, and the second adhesive layer 220 is used to bond the battery string layer 300 to the second encapsulation layer 120, thereby forming a robust sealed structure to prevent moisture and impurities from entering. The material of the first adhesive layer 210 includes at least one of EVA, POE, and EPE.

[0042] Since the first opening 121 would compromise the integrity of the second encapsulation layer 120 and could become a channel for moisture intrusion, a water-blocking structure is needed to seal and compensate for the first opening 121. Specifically, Figure 2 This is a cross-sectional schematic diagram of a photovoltaic module according to an embodiment, with reference to... Figure 2 The photovoltaic module also includes a first water-blocking layer 410 and a second water-blocking layer 420. The first water-blocking layer 410 fills the first opening 121 of the second encapsulation layer 120, and the second water-blocking layer 420 is disposed on at least a portion of the surface of the second encapsulation layer 120 facing the first water-blocking layer 410. That is, the second water-blocking layer 420 may be provided between both the first water-blocking layer 410 and the second encapsulation layer 120, or the second water-blocking layer 420 may be provided in a partial area between the first water-blocking layer 410 and the second water-blocking layer 420.

[0043] The adhesion between the second water-blocking layer 420 and the second encapsulation layer 120 is better than that between the first water-blocking layer 410 and the second encapsulation layer 120, and the water vapor transmission rate of the first water-blocking layer 410 is lower than that of the second water-blocking layer 420. Therefore, the second water-blocking layer 420 may include a central region and a peripheral region. Depending on the location where the first water-blocking layer 410 is prone to detach from the second encapsulation layer 120, the first water-blocking layer 410 may be provided in at least one of the central region and the peripheral region to reduce the risk of detachment between the first water-blocking layer 410 and the second encapsulation layer 120.

[0044] In the embodiments of the application, a first opening 121 is provided in the second encapsulation layer 120 to facilitate the outgoing of the busbar 310 of the battery string layer 300, thereby supporting the transmission of electrical signals in the battery string layer 300. For the area of ​​the first opening 121, which is prone to moisture intrusion, a first water-blocking layer 410 provides excellent water-blocking capability, while a second water-blocking layer 420 enhances the connection reliability between the first water-blocking layer 410 and the second encapsulation layer 120, preventing the first water-blocking layer 410 from detaching from the second encapsulation layer 120 due to long-term humid and hot environments. Therefore, the embodiments of this application provide a photovoltaic module that is easy to encapsulate battery strings and has high water-blocking reliability.

[0045] In one embodiment, the first water-blocking layer 410 further extends to cover a first surface of the second encapsulation layer 120 near the second adhesive film layer 220 and / or a second surface of the second encapsulation layer 120 away from the second adhesive film layer 220. Specifically, as Figure 2 As shown, the first water-blocking layer 410 also extends to cover a first surface of the second encapsulation layer 120 on the side near the second adhesive film layer 220, and extends to cover a second surface of the second encapsulation layer 120 on the side away from the second adhesive film layer 220. In some embodiments, the first water-blocking layer 410 extends only to cover the first surface of the second encapsulation layer 120 on the side near the second adhesive film layer 220, or extends only to cover the second surface of the second encapsulation layer 120 on the side away from the second adhesive film layer 220.

[0046] Furthermore, the extension direction of the portion of the laminated busbar 310 extending through the first opening 121 is parallel to the extension direction of the second encapsulation layer 120, and the first water-blocking layer 410 covers the portion of the busbar 310 extending through the first opening 121 to further enhance the water-blocking effect of the first water-blocking layer 410. Specifically, the thickness of the first water-blocking layer 410 located on the second surface of the second encapsulation layer 120 can be 2 to 3 times the thickness of the busbar 310, for example, 2 times, 2.5 times, 3 times, etc. The aforementioned thickness of the first water-blocking layer 410 can ensure effective coverage of the portion of the busbar 310 near the first opening 121, ensuring the water-blocking effect of the first water-blocking layer 410 and avoiding the problem of excessive thickness of the photovoltaic module due to excessive thickness of the first water-blocking layer 410.

[0047] The second water-blocking layer 420 covers the inner wall of the first opening 121 of the second encapsulation layer 120, and also covers a portion of the first surface and a portion of the second surface of the second encapsulation layer 120. Specifically, the first water-blocking layer 410 and the second water-blocking layer 420 are sequentially disposed between the manifold 310 in the first opening 121 and the inner wall of the first opening 121, wherein the first water-blocking layer 410 and the manifold 310 have good adhesion and are not easily detached from each other. Therefore, to improve the water-blocking effect at the first opening 121, the second water-blocking layer 420 does not need to be disposed between the first water-blocking layer 410 and the manifold 310. Furthermore, the thickness of the first water-blocking layer 410 between the manifold 310 in the first opening 121 and the inner wall of the first opening 121 is greater than the thickness of the second water-blocking layer 420. The thickness of the second water-blocking layer 420 should be as small as possible and cover as large an area as possible between the first water-blocking layer 410 and the second encapsulation layer 120, so as to ensure the reliability of the connection between the first water-blocking layer 410 and the inner wall of the first opening 121, and to make the first water-blocking layer 410 have a sufficiently large thickness to achieve better water-blocking performance.

[0048] For example, the second encapsulation layer 120 can be pre-treated to form a second water-blocking layer 420 at the first opening 121 of the second encapsulation layer 120. Then, the first encapsulation layer 110, the first adhesive film layer 210, the battery string layer 300, the second adhesive film layer 220, and the second encapsulation layer 120 are stacked. During the stacking process, the corresponding material of the first water-blocking layer 410 is placed in or around the first opening 121 and laminated to form the desired stacked structure of the first water-blocking layer 410 and the second water-blocking layer 420. The above arrangement allows for better control over the formation position of the second water-blocking layer 420, reducing the problem of poor coverage of the second encapsulation layer 120 near the first opening 121 due to positional deviation of the second water-blocking layer 420.

[0049] Alternatively, the first encapsulation layer 110, the first encapsulating film layer 210, the battery string layer 300, the second encapsulating film layer 220, and the second encapsulation layer 120 can be directly stacked. During the stacking process, the corresponding materials of the first water-blocking layer 410 and the second water-blocking layer 420 are placed in the first opening 121 or in the peripheral area of ​​the first opening 121, and the required stacked structure of the first water-blocking layer 410 and the second water-blocking layer 420 is formed in one step through lamination. The above-described method requires fewer process steps, thus improving the encapsulation efficiency of photovoltaic modules.

[0050] It should be noted that the above two methods of preparing the first water-blocking layer 410 and the second water-blocking layer 420 are only for illustrative purposes and are not intended to limit the scope of protection of this embodiment. The first water-blocking layer 410 and the second water-blocking layer 420 located near the first opening 121 can also be formed in other ways. As long as the structure of the first water-blocking layer 410 and the second water-blocking layer 420 in the photovoltaic module is the same as that in the figure, they all fall within the scope of protection of this embodiment.

[0051] In one embodiment, the orthographic projection of the second water-blocking layer 420 onto the second encapsulation layer 120 covers the first opening 121, and the entire orthographic projection of the second water-blocking layer 420 onto the second encapsulation layer 120 falls within the orthographic projection of the first water-blocking layer 410 onto the second encapsulation layer 120. The fact that the orthographic projection of the second water-blocking layer 420 onto the second encapsulation layer 120 covers the first opening 121 ensures sufficient contact area between the second water-blocking layer 420 and the first opening 121. Furthermore, the fact that the entire orthographic projection of the second water-blocking layer 420 onto the second encapsulation layer 120 falls within the orthographic projection of the first water-blocking layer 410 onto the second encapsulation layer 120 prevents excessive use of the second water-blocking layer 420 and results in a more aesthetically pleasing finished photovoltaic module after lamination.

[0052] In one embodiment, the first water-blocking layer 410 is made of butyl rubber, and the second water-blocking layer 420 is made of POE (polyolefin elastomer). Butyl rubber has the lowest water vapor transmission rate among known organic materials used for photovoltaic module encapsulation; however, it suffers from poor adhesion to glass, making it prone to delamination failure. While POE has a slightly higher water vapor transmission rate than butyl rubber, it is still significantly lower than that of EVA film, etc. Therefore, adding a second thermoplastic POE with excellent water-blocking properties and good adhesion to glass can effectively improve the moisture and heat resistance reliability of the photovoltaic module. Moreover, butyl rubber is less expensive than POE; the encapsulation method combining butyl rubber and POE in this embodiment can further reduce the encapsulation cost of the photovoltaic module while ensuring encapsulation reliability.

[0053] In one embodiment, the basis weight of the POE material in the second water-blocking layer 420 is 100 g / m². 2 Up to 500g / m 2 .

[0054] This application also provides a method for manufacturing a photovoltaic module. This method can be used to manufacture the photovoltaic module shown in the figure. Figure 3 This is one of the flowcharts for a method of manufacturing a photovoltaic module according to an embodiment. Figure 4 This is a cross-sectional schematic diagram of a photovoltaic module after step S104 of one embodiment, with reference to... Figure 3 Combined with reference Figure 3 and Figure 4 The method for preparing photovoltaic modules includes steps S102 to S106.

[0055] Step S102: A first encapsulation layer 110 is provided, and a first adhesive film layer 210, a battery string layer 300, a second adhesive film layer 220 and a second encapsulation layer 120 are sequentially stacked on the first encapsulation layer 110.

[0056] The cell string layer 300 is the core structure of the photovoltaic module, comprising multiple solar cells connected by interconnecting strips and busbars 310 to convert incident light energy into electrical energy. The types of solar cells include, but are not limited to, any of the following: TOPCon (tunneling oxide passivated contact), HJT (heterojunction cell), IBC (fully back contact cell), and perovskite cell.

[0057] The first encapsulation layer 110 and the second encapsulation layer 120 can be glass, including but not limited to tempered glass. The first encapsulation layer 110 and the second encapsulation layer 120 provide physical protection for the internal cell string layer 300, preventing external environmental factors (such as rain and sand) from corroding the internal cells. The second encapsulation layer 120 has a first opening 121, the shape of which includes, but is not limited to, any one of a circle, square, or rectangle. The busbar 310 extends through the first opening 121 to the outside of the photovoltaic module. Specifically, the busbar 310 can be connected to an external junction box, other components, or other parts to simplify the installation and maintenance of the photovoltaic module.

[0058] The first adhesive layer 210 and the second adhesive layer 220 serve as bonding materials. The first adhesive layer 210 is used to bond the battery string layer 300 to the first encapsulation layer 110, and the second adhesive layer 220 is used to bond the battery string layer 300 to the second encapsulation layer 120, thereby forming a robust sealed structure to prevent moisture and impurities from entering. The material of the first adhesive layer 210 includes at least one of EVA, POE, and EPE.

[0059] Step S104: After the step of setting the second encapsulation layer 120, a sealing material layer is formed.

[0060] The sealing material layer, when projected onto the second sealing layer, covers the first opening 121. The sealing material layer comprises a first water-blocking material layer 411 and a second water-blocking material layer 421 stacked together, with the first water-blocking material layer 411 disposed on the side of the second water-blocking material layer 421 furthest from the second encapsulation layer 120. The adhesion between the second water-blocking material layer 421 and the second encapsulation layer 120 is superior to that between the first water-blocking material layer 411 and the second encapsulation layer 120, and the water vapor permeability of the first water-blocking material layer 411 is lower than that of the second water-blocking material layer 421.

[0061] Step S106: Lamination is performed on the first encapsulation layer 110, the first adhesive film layer 210, the battery string layer 300, the second adhesive film layer 220, and the second encapsulation layer 120, so that the first water-blocking layer 410 fills the first opening 121 of the second encapsulation layer 120, and the second water-blocking layer 420 is disposed on at least a portion of the surface of the second encapsulation layer 120 facing the first water-blocking layer 410.

[0062] In the embodiments of the application, based on the material properties of the first water-blocking material layer 411 and the second water-blocking material layer 421, for the first opening 121 area which is prone to moisture intrusion, the first water-blocking layer 410 corresponding to the first water-blocking material layer 411 is used to provide excellent water-blocking capability, and the second water-blocking layer 420 corresponding to the second water-blocking material layer 421 is used to enhance the connection reliability between the first water-blocking layer 410 and the second encapsulation layer 120, so as to avoid the first water-blocking layer 410 and the second encapsulation layer 120 from detaching due to long-term humid and hot environment. Therefore, the embodiments of this application provide a method for manufacturing a photovoltaic module that is easy to encapsulate battery strings and has high water-blocking reliability.

[0063] Figure 5 This is a second flowchart illustrating a method for manufacturing a photovoltaic module according to one embodiment. Figure 6 This is a cross-sectional schematic diagram of a photovoltaic module after step S206 of one embodiment, in conjunction with reference to... Figure 5 and Figure 6 The method for preparing photovoltaic modules includes steps S202 to S208.

[0064] Step S202: A first encapsulation layer 110 is provided, and a first adhesive film layer 210, a battery string layer 300, and a second adhesive film layer 220 are sequentially stacked on the first encapsulation layer 110.

[0065] The cell string layer 300 is the core structure of the photovoltaic module, comprising multiple solar cells connected by interconnecting strips and busbars 310 to convert incident light energy into electrical energy. The types of solar cells include, but are not limited to, any of the following: TOPCon (tunneling oxide passivated contact), HJT (heterojunction cell), IBC (fully back contact cell), and perovskite cell.

[0066] The first encapsulation layer 110 can be glass, including but not limited to tempered glass. The first encapsulation layer 110 is used to provide physical protection for the internal battery string layer 300 to prevent external environment (such as rain, sand) from corroding the internal battery cells.

[0067] The first adhesive layer 210 and the second adhesive layer 220 serve as bonding materials. The first adhesive layer 210 is used to bond the battery string layer 300 to the first encapsulation layer 110, and the second adhesive layer 220 is used to bond the battery string layer 300 to the second encapsulation layer 120, thereby forming a robust sealed structure to prevent moisture and impurities from entering. The material of the first adhesive layer 210 includes at least one of EVA, POE, and EPE.

[0068] Step S204: Form a sealing material layer.

[0069] The sealing material layer, when projected onto the second sealing layer, covers the first opening 121. The sealing material layer comprises a first water-blocking material layer 411 and a second water-blocking material layer 421 stacked together, with the first water-blocking material layer 411 disposed on the side of the second water-blocking material layer 421 furthest from the second encapsulation layer 120. The adhesion between the second water-blocking material layer 421 and the second encapsulation layer 120 is superior to that between the first water-blocking material layer 411 and the second encapsulation layer 120, and the water vapor permeability of the first water-blocking material layer 411 is lower than that of the second water-blocking material layer 421.

[0070] Step S206: After forming the sealing material layer, a second encapsulation layer 120 is provided on the side of the sealing material layer away from the second adhesive film layer 220.

[0071] The second encapsulation layer 120 can be glass, including but not limited to tempered glass. The second encapsulation layer 120 provides physical protection for the internal cell string layer 300, preventing external environmental factors (such as rain and sand) from corroding the internal cells. The second encapsulation layer 120 has a first opening 121, the shape of which includes, but is not limited to, any one of a circle, square, or rectangle. A busbar 310 extends through the first opening 121 to the outside of the photovoltaic module. Specifically, the busbar 310 can be connected to an external junction box, other components, or other parts to simplify the installation and maintenance of the photovoltaic module.

[0072] Step S208: The first encapsulation layer 110, the first adhesive film layer 210, the battery string layer 300, the second adhesive film layer 220, and the second encapsulation layer 120 are laminated so that the first water-blocking layer 410 fills the first opening 121 of the second encapsulation layer 120, and the second water-blocking layer 420 is disposed on at least a portion of the surface of the second encapsulation layer 120 facing the first water-blocking layer 410.

[0073] In the embodiments of the application, based on the material properties of the first water-blocking material layer 411 and the second water-blocking material layer 421, for the first opening 121 area which is prone to moisture intrusion, the first water-blocking layer 410 corresponding to the first water-blocking material layer 411 is used to provide excellent water-blocking capability, and the second water-blocking layer 420 corresponding to the second water-blocking material layer 421 is used to enhance the connection reliability between the first water-blocking layer 410 and the second encapsulation layer 120, so as to avoid the first water-blocking layer 410 and the second encapsulation layer 120 from detaching due to long-term humid and hot environment. Therefore, the embodiments of this application provide a method for manufacturing a photovoltaic module that is easy to encapsulate battery strings and has high water-blocking reliability.

[0074] It is understood that, in the embodiments of this application, the sealing material layer can be formed either before or after the step of setting the second encapsulation layer 120. The two fabrication processes described above can form similar structures for the first water-blocking layer 410 and the second water-blocking layer 420. Therefore, the photovoltaic module fabrication method of the embodiments of this application has better process flexibility, allowing for flexible selection of the timing for setting the sealing material layer according to process requirements.

[0075] In one embodiment, the outer contour shape of the first water-blocking material layer 411 is the same as that of the second water-blocking material layer 421, and the outer contour dimension of the first water-blocking material layer 411 is larger than that of the second water-blocking material layer 421. Specifically, the outer contour shapes of the first water-blocking material layer 411 and the second water-blocking material layer 421 can be, but are not limited to, circles, squares, rectangles, etc. By setting the outer contour dimension of the first water-blocking material layer 411 to be larger than that of the second water-blocking material layer 421, the finished photovoltaic module formed after lamination can be more aesthetically pleasing.

[0076] Figure 7(a) is a schematic diagram of one embodiment of the first water-blocking material layer 411, and Figure 7(b) is a schematic diagram of another embodiment of the first water-blocking material layer 411. Referring to Figures 7(a) and 7(b), in one embodiment, a first opening 121 is provided for two busbars 310 to pass through, and a first water-blocking material layer 411 is provided with two second openings 412, each second opening 412 being used for a corresponding busbar 310 to extend to the outside of the photovoltaic module. For example, if the cross-sectional shape of the busbar 310 along the direction perpendicular to the extension direction is elongated, the shape of the second opening 412 can also be elongated, and the size of the second opening 412 is slightly larger than the cross-sectional size of the busbar 310, thereby ensuring that the busbar 310 can pass smoothly through the second opening 412.

[0077] Figure 8(a) is a schematic diagram of one embodiment of the second water-blocking material layer 421, and Figure 8(b) is a schematic diagram of another embodiment of the second water-blocking material layer 421. Referring to Figures 8(a) and 8(b), in one embodiment, the second water-blocking material layer 421 is provided with a third opening 422. The shape of the third opening 422 may be, but is not limited to, circular, square, rectangular, etc. The orthographic projection size of the third opening 422 on the second sealing layer is smaller than the size of the first opening 121. The two busbars 310 are led out to the outside of the photovoltaic module through the same third opening 422. Specifically, by setting the two busbars 310 to be led out to the outside of the photovoltaic module through the same third opening 422, the material of the second water-blocking material layer 421 will not be squeezed into the two busbars 310 during the lamination process, ensuring that the material between the two busbars 310 is the material of the first water-blocking material layer 411, reducing the path of water vapor entering the interior of the photovoltaic module through the two busbars 310, thereby improving the water-blocking performance of the photovoltaic module.

[0078] In one embodiment, the thickness of the first water-blocking material sublayer 411 is 70% to 110% of the thickness of the second encapsulation layer 120. For example, if the second encapsulation layer 120 is glass with a thickness of 2 mm, the thickness of the first water-blocking material sublayer 411 can be 1.5-2 mm to ensure that the material of the first water-blocking material sublayer 411 can smoothly fill the first opening 121 during the lamination process.

[0079] To more clearly illustrate the advantages of the photovoltaic modules according to the embodiments of this application, experimental data of three photovoltaic module embodiments and three comparative photovoltaic modules are provided herein for comparative explanation. The embodiments refer to photovoltaic modules prepared using the photovoltaic module preparation method of this application, while the comparative examples refer to photovoltaic modules prepared without using the photovoltaic module preparation method of this application.

[0080] Example 1:

[0081] The experiment used small-sized glass as the first encapsulation layer 110 and the second encapsulation layer 120. The small-sized glass was 300*300mm in size and 2mm thick, with the first opening 121 being a circular opening with a diameter of 12mm. The first water-blocking material layer 411 was made of butyl rubber, with an outer contour of a circle with a diameter of 20mm and a thickness of 2mm. The second water-blocking material layer 421 was made of thermoplastic POE with a basis weight of 300g / m2, with an outer contour of a circle with a diameter of 15mm. The third opening 422 in the middle had an outer contour of a circle with a diameter of 8mm and was placed on the outside of the second encapsulation layer 120. After lamination, a HAST (Highly Accelerated Stress Test) experiment was conducted. After 288 hours, no blackening of the EL (electrolyte layer) was observed, indicating that no moisture intrusion occurred.

[0082] Example 2:

[0083] The experiment used small-sized glass as the first encapsulation layer 110 and the second encapsulation layer 120. The small-sized glass had dimensions of 300*300mm and a thickness of 2mm, with the first opening 121 being a circular opening with a diameter of 12mm. The first water-blocking material layer 411 was made of butyl rubber, with an outer contour of a square with a side length of 15mm and a thickness of 2mm. The second water-blocking material layer 421 was made of thermoplastic POE with a basis weight of 400g / m2, with an outer contour of a circle with a diameter of 13mm. The third opening 422 in the middle had an outer contour of a circle with a diameter of 6mm and was placed on the outside of the second encapsulation layer 120. After lamination, a HAST test was performed. After 288 hours, no blackening of the EL (electroluminescent film) was observed, indicating that no moisture intrusion occurred.

[0084] Example 3:

[0085] The experiment used small-sized glass as the first encapsulation layer 110 and the second encapsulation layer 120. The small-sized glass had dimensions of 300*300mm and a thickness of 2mm, with the first opening 121 being a circular opening with a diameter of 12mm. The first water-blocking material layer 411 was made of butyl rubber, with an outer contour of a circle with a diameter of 20mm and a thickness of 2mm. The second water-blocking material layer 421 was made of thermoplastic POE with a basis weight of 300g / m2, with an outer contour of a circle with a diameter of 15mm. The third opening 422 in the middle had a contour of a circle with a diameter of 8mm and was placed inside the second encapsulation layer 120. After lamination, a HAST test was performed. After 288 hours, no blackening of the EL (electrolyte layer) was observed, indicating that no moisture intrusion occurred.

[0086] Comparative Example 1:

[0087] Experiments were conducted using small-sized glass as the first encapsulation layer 110 and the second encapsulation layer 120. The small-sized glass had dimensions of 300*300mm and a thickness of 2mm, with the first opening 121 being a circular opening with a diameter of 12mm. The first water-blocking material layer 411 was made of butyl rubber, with an outer contour of a circle with a diameter of 20mm and a thickness of 2mm, without the addition of thermoplastic POE, and was placed on the outside of the second encapsulation layer 120. After lamination, a HAST test was performed. After 288 hours, the small-sized glass showed blackening of the EL (electroluminescent plate) at the edge near the opening, indicating that moisture had intruded.

[0088] Comparative Example 2:

[0089] Experiments were conducted using small-sized glass as the first encapsulation layer 110 and the second encapsulation layer 120. The small-sized glass measures 300*300mm and has a thickness of 2mm, with the first opening 121 being a circular opening with a diameter of 12mm. The first water-blocking material layer 411 is made of butyl rubber, with an outer contour of a circle with a diameter of 20mm and a thickness of 2mm. The second water-blocking material layer 421 is made of thermoplastic POE with a basis weight of 300g / m2, with an outer contour of a circle with a diameter of 30mm. The third opening 422 in the middle has a contour of a circle with a diameter of 8mm and is placed on the outside of the second encapsulation layer 120. After lamination, a HAST test was performed. After 288 hours, no blackening of the EL (electroluminescent plate) was observed, indicating no moisture intrusion. However, the edges of the pores showed a mixture of black and white, which was aesthetically unappealing.

[0090] Comparative Example 3:

[0091] The experiment used small-sized glass as the first encapsulation layer 110 and the second encapsulation layer 120. The small-sized glass was 300*300mm in size and 2mm thick, with the first opening 121 being a circular opening with a diameter of 12mm. The first water-blocking material layer 411 was made of butyl rubber, with an outer contour of a circle with a diameter of 50mm and a thickness of 2mm. The second water-blocking material layer 421 was made of thermoplastic POE with a basis weight of 300g / m2, with an outer contour of a circle with a diameter of 15mm. The third opening 422 in the middle had an outer contour of a circle with a diameter of 8mm and was placed on the outside of the second encapsulation layer 120. After lamination, a HAST test was performed. After 288 hours, no blackening of the EL (electroluminescent film) was observed, indicating no moisture intrusion. However, the butyl rubber was too large, resulting in a large, protruding black ring, which was unsightly.

[0092] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0093] 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.

[0094] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this 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 protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A photovoltaic module, characterized in that, The photovoltaic module includes a first encapsulation layer, a first encapsulating film layer, a battery string layer, a second encapsulating film layer, and a second encapsulation layer stacked in sequence. The second encapsulation layer has a first opening. The battery string layer is connected to a busbar, and the busbar extends out to the outside of the photovoltaic module through the first opening. The photovoltaic module further includes a first water-blocking layer and a second water-blocking layer, wherein the first water-blocking layer fills a first opening in the second encapsulation layer and the second water-blocking layer is disposed on at least a portion of the surface of the second encapsulation layer facing the first water-blocking layer. The adhesion between the second water-blocking layer and the second encapsulation layer is better than that between the first water-blocking layer and the second encapsulation layer, and the water vapor transmission rate of the first water-blocking layer is lower than that of the second water-blocking layer.

2. The photovoltaic module according to claim 1, characterized in that, The first water-blocking layer also extends to cover the first surface of the second encapsulation layer on the side near the second adhesive film layer; The second water-blocking layer covers the inner wall of the first opening of the second encapsulation layer, and covers a portion of the first surface of the second encapsulation layer and a portion of the second surface of the second encapsulation layer on the side away from the second film layer.

3. The photovoltaic module according to claim 1, characterized in that, The first water-blocking layer also extends to cover the second surface of the second encapsulation layer on the side away from the second adhesive film layer; The second water-blocking layer covers the inner wall of the first opening of the second encapsulation layer, and also covers a portion of the first surface and a portion of the second surface of the second encapsulation layer near the second film layer.

4. The photovoltaic module according to claim 1, characterized in that, The first water-blocking layer also extends to cover a first surface of the second encapsulation layer on the side close to the second adhesive film layer, and a second surface of the second encapsulation layer on the side away from the second adhesive film layer; The second water-blocking layer covers the inner wall of the first opening of the second encapsulation layer, and also covers a portion of the first surface and a portion of the second surface of the second encapsulation layer.

5. The photovoltaic module according to claim 1, characterized in that, The material of the first water-blocking layer includes butyl rubber, and the material of the second water-blocking layer includes POE.

6. The photovoltaic module according to claim 5, characterized in that, The basis weight of the POE material in the second water-blocking layer is 100 g / m³. 2 Up to 500 g / m 2 .

7. The photovoltaic module according to claim 1, characterized in that, The orthographic projection of the second water-blocking layer onto the second encapsulation layer covers the first opening, and the orthographic projection of the second water-blocking layer onto the second encapsulation layer falls entirely within the orthographic projection of the first water-blocking layer onto the second encapsulation layer.

8. The photovoltaic module according to claim 1, characterized in that, One of the first openings is for the passage of both of the busbars.

9. The photovoltaic module according to claim 1, characterized in that, The diameter of the first opening is 10 mm to 15 mm.

10. The photovoltaic module according to claim 1, characterized in that, The thickness of the first encapsulation layer and / or the second encapsulation layer is 1.5 mm to 2.5 mm.

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