Photovoltaic module and photovoltaic system

Abstract

The present application relates to the technical field of photovoltaics. Disclosed is a photovoltaic module, which is configured to solve the problem of encapsulation and sealing. The photovoltaic module comprises: a cover plate and a back plate disposed opposite each other; a cell group disposed between the cover plate and the back plate; an encapsulation adhesive film, by means of which the cell group is fixed to the cover plate and the back plate; and a water barrier layer disposed on the outer side of the encapsulation adhesive film, wherein the water vapor transmission rate of the water barrier layer is less than the water vapor transmission rate of the encapsulation adhesive film, and in a direction from the water barrier layer to the encapsulation adhesive film, the dimension of the water barrier layer is less than the dimension of the encapsulation adhesive film. Compared with an existing photovoltaic module, the water vapor transmission rate of the water barrier layer is less than the water vapor transmission rate of the encapsulation adhesive film, and the water barrier layer is located on the outer side of the encapsulation adhesive film. Therefore, for the encapsulated and protected cell group, the closer the cell group is to the outer side, the closer the cell group is to the air environment, the better the water barrier performance is. The combination of the outer water barrier layer and the inner encapsulation adhesive film can effectively prevent water vapor ingress, thereby playing a role in ensuring the reliability of electrodes on a cell.

Description

A photovoltaic module and photovoltaic system

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese application No. 202510081336.3, filed on January 17, 2025, entitled “A Photovoltaic Module and Photovoltaic System”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of photovoltaic technology, and in particular to a photovoltaic module and a photovoltaic system. Background Technology

[0004] With the development of photovoltaic module technology, cost reduction has become an important development direction. Battery cost accounts for a significant portion of photovoltaic module cost, and within battery cost, the consumption of silver paste for the electrodes constitutes a major part. To reduce silver paste consumption, silver-copper pastes, and even silver-free pastes (such as copper pastes), have been developed as the main component of the paste. However, with the introduction of other metal pastes, which are less stable than silver pastes, moisture can still seep in during outdoor operation of photovoltaic modules, despite encapsulation, affecting the performance of non-pure silver electrodes and causing blackening or even failure. Summary of the Invention

[0005] The purpose of this application is to provide a photovoltaic module and a photovoltaic system to improve the water-blocking measures of the photovoltaic module's encapsulation, prevent moisture intrusion as much as possible, thereby ensuring the reliability of the non-silver electrode battery and reducing costs.

[0006] In a first aspect, this application provides a photovoltaic module, comprising:

[0007] The cover and back plate are set opposite each other;

[0008] The battery pack is located between the cover plate and the back plate;

[0009] The battery pack is fixed to the cover plate and back plate by the encapsulation film.

[0010] A water-blocking layer is disposed on the outside of the encapsulating film; wherein the water vapor transmission rate of the water-blocking layer is less than that of the encapsulating film, and the size of the water-blocking layer is smaller than that of the encapsulating film in the direction from the water-blocking layer to the encapsulating film.

[0011] With the above technical solution, the water vapor transmission rate of the water-blocking layer is lower than that of the encapsulating film, and the water-blocking layer is located on the outside of the encapsulating film. Therefore, for the encapsulated battery pack, the closer it is to the outside and the closer it is to the air environment, the better its water-blocking ability. The combination of the outer water-blocking layer and the inner encapsulating film can effectively prevent water vapor intrusion, thus protecting the reliability of the electrodes on the battery cells. Furthermore, while the water vapor transmission rate of the water-blocking layer is lower than that of the encapsulating film, the size of the water-blocking layer is smaller than the size of the encapsulating film in the direction from the water-blocking layer to the encapsulating film. The water-blocking layer mainly functions to block water, while the encapsulating film mainly functions to protect and fix the battery pack. When the size of the water-blocking layer is smaller than the size of the encapsulating film, priority can be given to ensuring the reliability of the battery pack and preventing fragmentation, further improving the reliability of the electrodes on the battery cells included in the battery pack.

[0012] In some possible implementations, the water vapor permeability of the water-blocking layer is less than or equal to 0.12 g / (m²). 2 ·d). This further improves the water-blocking effect of the water-blocking layer.

[0013] In some possible implementations, the water-blocking layer must satisfy at least one of the following conditions:

[0014] A. The water vapor permeability of the water-blocking layer is less than or equal to 0.03 g / (m²). 2 ·d);

[0015] B. The water-blocking layer includes butyl rubber, and the encapsulating film includes EVA;

[0016] C. In the direction from the water-blocking layer to the encapsulating film, the size of the water-blocking layer is less than or equal to 0.1 times the size of the encapsulating film.

[0017] When using the above technical solution, the water vapor permeability of the water-blocking layer is less than or equal to 0.03 g / (m²). 2 (d) At this point, the manufactured photovoltaic module exhibits excellent water-blocking performance, and the electrode structure of the module can operate reliably in high-humidity environments. The water-blocking layer uses butyl rubber, which can meet the requirement that the water vapor transmission rate is less than or equal to 0.03 g / (m²). 2 •d) The water vapor transmittance is much lower than that of the encapsulating film, resulting in excellent water-blocking performance. The encapsulating film uses EVA combined with butyl rubber as the main material for the water-blocking layer. Both materials can bond and fix well to the cover plate and back sheet, improving the structural stability of the photovoltaic module and reducing the risk of delamination and peeling of the module layers. Water-blocking layers with water-blocking effects often have low light transmittance, and their size is less than or equal to 0.1 times the size of the encapsulating film, minimizing the adverse effects on the module's light absorption rate.

[0018] In some possible implementations, the photovoltaic module also includes a frame and an auxiliary water-blocking layer. The frame is fixed to the outer periphery of the cover plate and back sheet via the auxiliary water-blocking layer. The auxiliary water-blocking layer is made of silicone, and the frame can be bonded and sealed around the edges of the photovoltaic module with silicone, while also providing a certain degree of water-blocking effect. The water vapor transmission rate of the auxiliary water-blocking layer is greater than that of the encapsulating film, which can effectively block some water vapor from passing through in the three-layer water-blocking structure, thereby improving the water-blocking effect.

[0019] In some possible implementations, the water-blocking layer is located between the cover plate and the back sheet, and an encapsulating film wraps around the surface of the cells included in the battery pack. The encapsulating film also exists between the cells and the water-blocking layer. The water-blocking layer, located between the cover plate and the back sheet, can reduce the side length of the photovoltaic module and, for butyl rubber, improves the fixing and sealing effect between the butyl rubber and the cover plate and back sheet. The encapsulating film wrapping around the surface of all the cells in the battery pack improves the buffering, fixing, and insulation effect on the cells. Furthermore, the encapsulating film separating the cells from the water-blocking layer reduces the risk of damage and microcracks to the cells caused by direct contact between the relatively hard water-blocking layer and the cells.

[0020] In some possible implementations, the water-blocking layer is located between the cover plate and the back plate; the water-blocking layer and the encapsulating film satisfy at least one of the following conditions:

[0021] D. The water-blocking layer and the encapsulating film are in contact and the peel force between them is less than or equal to 5 N / cm;

[0022] E. There are gaps or holes between the water-blocking layer and the encapsulating film.

[0023] When the above technical solution is adopted, if the water-blocking layer is located between the cover plate and the back plate, the water-blocking layer and the encapsulating film are simply in contact or bonded, and there is no cross-linking or chemical fusion between the two. The peel force is less than or equal to 5 N / cm, and there are gaps or pores between the water-blocking layer and the encapsulating film to prevent the encapsulating film from intruding into the water-blocking layer and affecting the water-blocking effect of the water-blocking layer.

[0024] In some possible implementations, the melting point of the water-blocking layer is lower than that of the encapsulating film. During the photovoltaic module manufacturing process, the water-blocking layer melts first upon heating and bonds with the cover plate and back sheet. This prevents the encapsulating film from melting first and then penetrating into the water-blocking layer, as well as between the water-blocking layer and the cover plate and back sheet, thus ensuring the water-blocking effect of the water-blocking layer.

[0025] In some possible implementations, the water-blocking layer is located between the cover plate and the back sheet. In the width direction of the water-blocking layer, more than 70% of its width from the outside in is in direct contact with the cover plate and / or back sheet. This arrangement, with the encapsulating film penetrating a smaller area between the water-blocking layer and the cover plate and / or back sheet (more than 70% from the outside in), reduces the impact of the encapsulating film on the water-blocking effect of the water-blocking layer. It also ensures a good seal between the water-blocking layer and the cover plate and / or back sheet, reducing the risk of moisture entering the photovoltaic module through gaps between the water-blocking layer and the cover plate and / or back sheet.

[0026] In some possible implementations, the water-blocking layer is located between the cover plate and the back plate; the overlap width between the orthographic projection of the water-blocking layer on the cover plate and the orthographic projection of the encapsulating film on the cover plate is 0mm-1mm; the overlap width between the orthographic projection of the water-blocking layer on the back plate and the orthographic projection of the encapsulating film on the back plate is also 0mm-1mm. With this configuration, the area where the encapsulating film intrudes between the water-blocking layer and the cover plate and / or back plate is small, reducing the impact of the encapsulating film on the water-blocking effect of the water-blocking layer.

[0027] In some possible implementations, the water-blocking layer is located between the cover plate and the back plate; the water-blocking layer must satisfy at least one of the following conditions:

[0028] F. The width of the water-blocking layer is 3mm-16mm;

[0029] G. The difference between the width of the first position and the width of the second position of the water-blocking layer is less than or equal to 40% of the larger of the two widths.

[0030] With the above technical solution, the water-blocking layer is located between the cover plate and the back plate. If the width of the water-blocking layer is less than 3mm, it is too small and the water-blocking effect is not ideal. If the width of the water-blocking layer is greater than 16mm, it is too wide, occupying too much space at the edge of the photovoltaic module, increasing the size of the photovoltaic module or reducing the unit area power generation efficiency of the cells, and increasing the material cost of the water-blocking layer. A relatively uniform overall width of the water-blocking layer results in a more balanced water-blocking effect for the photovoltaic module.

[0031] In some possible implementations, the water-blocking layer is located between the cover plate and the back sheet; the water-blocking layer is bonded to both the cover plate and the back sheet, and there are no holes with a diameter greater than or equal to 0.5 mm between the water-blocking layer and the cover plate / back sheet, nor are there any holes with a diameter greater than or equal to 0.5 mm in the water-blocking layer itself. This configuration results in smaller holes between the water-blocking layer and the cover plate / back sheet, as well as smaller holes within the water-blocking layer itself, improving the sealing and bonding effect between the water-blocking layer and the cover plate / back sheet, and enhancing the sealing effect of the water-blocking layer itself, thereby improving the water-blocking performance of the photovoltaic module.

[0032] In some possible implementations, the water-blocking layer must satisfy at least one of the following conditions:

[0033] H. The water-blocking layer is located between the cover plate and the back plate; the adhesion between the water-blocking layer and the cover plate is greater than the adhesion between the encapsulating film and the cover plate; the adhesion between the water-blocking layer and the back plate is greater than the adhesion between the encapsulating film and the back plate.

[0034] I. The water-blocking layer is located between the cover plate and the back plate, and the peel force between the water-blocking layer and the cover plate and the back plate is greater than or equal to 200 N / cm;

[0035] J. The hardness of the water-blocking layer is greater than that of the encapsulating film.

[0036] With the above technical solution, the adhesion between the water-blocking layer and the cover plate and / or back plate is stronger, which improves the bonding and sealing effect between the water-blocking layer and the cover plate and / or back plate, thereby improving the water-blocking performance. The peel force between the water-blocking layer and the cover plate / back plate is greater than or equal to 200 N / cm, making it less likely to detach during use and transportation, thus improving the sealing and water-blocking performance. The hardness of the water-blocking layer is greater than that of the encapsulating film, and the water-blocking layer, located on the outside of the encapsulating film, can provide better support performance.

[0037] In some possible implementations, the water-blocking layer is disposed around the perimeter between the cover plate and the back sheet, and the encapsulating film is disposed between the cover plate and the back sheet and within the area enclosed by the water-blocking layer. This arrangement, with the water-blocking layer present around the perimeter between the cover plate and the back sheet, and the encapsulating film surrounded by the water-blocking layer, improves the water-blocking performance around the photovoltaic module.

[0038] In some possible implementations, the photovoltaic module also includes a water-blocking reinforcement layer; the water vapor transmission rate of the water-blocking reinforcement layer is lower than that of the water-blocking layer, and the water-blocking reinforcement layer is disposed at least at one of the following three locations: between the water-blocking layer and the cover plate, between the water-blocking layer and the back sheet, or on the side of the water-blocking layer facing away from the battery pack. The water-blocking performance of the photovoltaic module is further improved by incorporating the water-blocking reinforcement layer.

[0039] In some possible implementations, the outer edge of the water-blocking layer is flush with the outer edge of the cover plate; or the outer edge of the water-blocking layer protrudes from the outer edge of the cover plate.

[0040] With the above technical solution, the outer edge of the water-blocking layer is flush with the outer edges of the cover plate and the back plate. This maximizes the use of the edge area between the cover plate and the back plate for water-blocking sealing. Furthermore, the flush design, compared to a recessed design, facilitates a smoother bonding and fixation between the frame and the outer edges of the cover plate, water-blocking layer, and back plate, reducing gaps caused by positional differences and thus improving the sealing effect. The frame is fixed to the edge of the component via an auxiliary water-blocking layer. The outer edge of the water-blocking layer protrudes from the outer edge of the cover plate, ensuring sufficient width for the water-blocking layer and facilitating the encapsulation and excess adhesive effects between the cover plate, water-blocking layer, back plate stack, and frame.

[0041] In some possible implementations, an end-water-blocking tape is also provided between the outer periphery of the cover plate and back plate and the auxiliary water-blocking layer. The water vapor transmission rate of the end-water-blocking tape is greater than that of the water-blocking layer, but less than that of the encapsulating film. With this arrangement, the water vapor transmission performance is improved by the water-blocking structure composed of the end-water-blocking tape, the water-blocking layer, and the encapsulating film, which forms a stepped, non-linear change in water vapor transmission performance from the outside in.

[0042] In some possible implementations, the back panel has outlet holes, and a water-blocking structure is also provided at the outlet holes. The difference in water vapor permeability between the water-blocking structure and the water-blocking layer is less than 0.5 g / m. 2 ·d. In addition to setting water-blocking structures at the edges of photovoltaic modules, water-blocking structures are also set at the outlet holes on the back sheet. The water-blocking effect of the water-blocking structure is similar to that of the water-blocking layer, reducing the risk of water vapor entering the module from the outlet holes, thereby improving the overall sealing and water-blocking performance of the module.

[0043] In some possible implementations, the photovoltaic module also includes a frame and an auxiliary water-blocking layer. The frame is fixed to the outer periphery of the cover plate and the back plate by the auxiliary water-blocking layer. Along the side of the frame to the center of the battery pack, the auxiliary water-blocking layer, the water-blocking layer and the encapsulating film are arranged in sequence, and the water vapor permeability of the three decreases first and then increases. The water vapor permeability of the encapsulating film is less than that of the auxiliary water-blocking layer.

[0044] In some possible implementations, photovoltaic modules must meet at least one of the following conditions:

[0045] K. In the direction of the vertical upper surface of the cover plate, the orthographic projection of the frame overlaps the orthographic projection of the water-blocking layer;

[0046] L. An auxiliary water-blocking layer covers the outer surface of the water-blocking layer;

[0047] M. An end-water-blocking tape is provided between the auxiliary water-blocking layer and the side of the cover plate.

[0048] This design allows non-transparent water-blocking layers, such as those in black or gray, to be shielded by the top (A-side) of the frame, improving the appearance of the photovoltaic module. The auxiliary water-blocking layer covers the outer surface of the water-blocking layer, providing protection. The combination of the auxiliary water-blocking layer, the end-water-blocking tape, and the encapsulating film enhances water-blocking performance while facilitating the repair of the end-water-blocking tape.

[0049] In some possible implementations, the water-blocking layer is located outside the cover plate and the back plate; the water-blocking layer must meet at least one of the following conditions:

[0050] N. The cross-section of the water-blocking layer is C-shaped;

[0051] O. The water-blocking layer is made of aluminum foil tape. Thus, the water-blocking layer is wrapped around the outside of the cover plate and back plate, and fixed with aluminum foil tape. The water vapor permeability of the aluminum foil tape is much lower than that of the encapsulating film, thus improving the water-blocking and sealing performance. Furthermore, the water-blocking layer's location on the outside of the cover plate and back plate reduces the space occupied between them, allowing for a larger proportion of the battery pack and improving the photovoltaic module's power generation efficiency per unit area.

[0052] In some possible implementations, the outer side of the water-blocking layer is fixed to the frame by an auxiliary water-blocking layer. On a cross-section parallel to the thickness direction of the photovoltaic module and perpendicular to one side of the photovoltaic module, the cross-sectional shape of the auxiliary water-blocking layer is C-shaped, and the middle part of the auxiliary water-blocking layer is bonded to the water-blocking layer. The auxiliary water-blocking layer must meet at least one of the following conditions:

[0053] P. The two ends of the auxiliary water-blocking layer are respectively bonded to the cover plate and the back plate;

[0054] Q. The width of the auxiliary water-blocking layer bonded to the cover plate is 5mm-10mm. Thus, with the water-blocking layer located outside the cover plate and back plate, the auxiliary water-blocking layer has a C-shaped structure, wrapping around the outside of the water-blocking layer. Both ends of the auxiliary water-blocking layer are bonded to the cover plate and back plate. This auxiliary water-blocking layer improves the fixation of the water-blocking layer to the outside of the cover plate and back plate, making it less prone to detachment. If the width of the auxiliary water-blocking layer bonded to the cover plate is less than 5mm, the bonding effect between the auxiliary water-blocking layer and the cover plate, as well as the fixation effect of the frame, will be poor. If the width is greater than 10mm, it increases the amount of light-receiving area of ​​the battery blocked by the auxiliary water-blocking layer and increases material costs.

[0055] In some possible implementations, the water-blocking layer must satisfy at least one of the following conditions:

[0056] R. The width of the water-blocking layer bonded to the front of the cover plate and / or the back of the back plate is 2mm-5mm;

[0057] S. The adhesion between the water-blocking layer and the cover plate and back plate is greater than or equal to 5 N / cm.

[0058] When using the above technical solution, if the bonding width between the water-blocking layer and the front of the cover plate and / or the back of the back plate is less than 2mm, the bonding width of the water-blocking layer is too small, resulting in poor fixing effect. If the width is greater than 5mm, it can easily block the light-receiving area of ​​the battery and affect the bonding effect between the auxiliary water-blocking layer and the cover plate and back plate, causing unnecessary waste of materials. A bonding force of ≥5N / cm between the water-blocking layer and the cover plate and back plate ensures good bonding and fixing performance.

[0059] Secondly, this application also provides a photovoltaic system, including the photovoltaic modules described in any of the above claims. The beneficial effects of the photovoltaic system are the same as those of the first aspect and any of the above technical solutions, and will not be repeated here. Attached Figure Description

[0060] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0061] Figure 1 is a cross-sectional schematic diagram of a photovoltaic module provided in an embodiment of this application;

[0062] Figure 2 is a cross-sectional schematic diagram of another photovoltaic module provided in an embodiment of this application;

[0063] Figure 3 is a cross-sectional schematic diagram of another photovoltaic module provided in an embodiment of this application;

[0064] Figure 4 is a schematic diagram of the water-blocking effect of existing photovoltaic modules;

[0065] Figure 5 is a schematic diagram of the water-blocking effect of the photovoltaic module in the embodiment of this application.

[0066] The attached diagram is labeled as follows: 1 for the frame, 2 for the auxiliary water-blocking layer, 3 for the water-blocking layer, 4 for the encapsulation film, 5 for the battery pack, 6 for the cover plate, 7 for the back plate, and 8 for the end water-blocking tape. Detailed Implementation

[0067] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0068] 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 or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0069] 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 one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise expressly specified. "Several" means one or more, unless otherwise expressly specified.

[0070] In the description of this application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0071] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0072] As shown in Figures 1-3, this application provides a photovoltaic module including a cover plate 6, a back sheet 7, a battery pack 5, a water-blocking layer 3, and an encapsulating film 4. The cover plate 6 and back sheet 7 are arranged opposite each other. Both the cover plate 6 and back sheet 7 can be transparent, or the cover plate 6 can be transparent and the back sheet 7 can be non-transparent. The transparent plates can be transparent glass or transparent plastic sheets, etc., and the non-transparent plates can be non-transparent glass or non-transparent plastic sheets, etc. The battery pack 5 is disposed between the cover plate 6 and the back sheet 7, and the battery pack 5 includes multiple batteries arranged in an array and connected in series and parallel. An encapsulating film 4 is provided between the battery pack 5 and the cover plate 6, and between the battery pack 5 and the back sheet 7. The battery pack 5 is fixed to the cover plate 6 and the back sheet 7 by the encapsulating film 4. The water-blocking layer 3 is disposed on the outside of the encapsulating film 4, and the size of the water-blocking layer 3 is smaller than the size of the encapsulating film 4 in the direction from the water-blocking layer 3 to the encapsulating film 4.

[0073] For example, along the long side of the parallel component, the size of the water-blocking layer 3 is the width of the water-blocking layer, and the size of the encapsulating film 4 is the length of the encapsulating film. Along the short side of the parallel component, the size of the water-blocking layer 3 is the width of the water-blocking layer, and the size of the encapsulating film 4 is the width of the encapsulating film.

[0074] It should be understood that water vapor transmission rate refers to the amount of water vapor that passes through a unit area of ​​material per unit time. The unit is usually g / (m²). 2 ·d), indicating every 1m per day (24h) 2 The weight of water vapor passing through an area.

[0075] The water vapor transmission rate can be tested using existing methods such as GB 1037-88, GB / T 26253-2010, GB / T1037-2021, and GB / T 30412-2013. Preferably, the water-blocking layer and the encapsulating film are tested using the same method.

[0076] With the above technical solution, the water vapor transmission rate of the water-blocking layer 3 is less than that of the encapsulating film 4, and the water-blocking layer 3 is located on the outside of the encapsulating film 4. Therefore, for the encapsulated and protected battery pack 5, the closer it is to the outside and the closer it is to the air environment, the better its water-blocking ability. The combination of the outer water-blocking layer 3 and the inner encapsulating film 4 can effectively isolate water vapor intrusion, thus protecting the reliability of the electrodes on the battery cells. In addition, while the water vapor transmission rate of the water-blocking layer 3 is less than that of the encapsulating film 4, the size of the water-blocking layer 3 is smaller than the size of the encapsulating film 4 in the direction from the water-blocking layer 3 to the encapsulating film 4. The water-blocking layer 3 mainly functions to block water, while the encapsulating film 4 mainly functions to protect and fix the battery pack. When the size of the water-blocking layer 3 is smaller than the size of the encapsulating film 4, the reliability and fragmentation of the battery pack can be prioritized, further improving the reliability of the electrodes on the battery cells included in the battery pack 5.

[0077] As shown in Figures 4 and 5, Figure 4 illustrates the water-blocking effect of existing photovoltaic modules. It can be seen that without a water-blocking layer, moisture seeps into the edges of the existing photovoltaic modules, causing the edges of the non-silver paste cells to turn black. Figure 5 illustrates the water-blocking effect of a photovoltaic module with its four edges sealed according to the embodiments of this application. It can be seen that when the four edges of the photovoltaic module are entirely covered by the water-blocking structure of this application, the non-silver paste cells at the four edges of the photovoltaic module do not turn black, ensuring the reliability of the non-silver paste cells.

[0078] In some embodiments, the water vapor permeability of the water-blocking layer 3 is less than or equal to 4 g / (m²). 2 •d). For example, the water vapor permeability of the water-blocking layer 3 can be 0.01 g / (m). 2 ·d), 0.03g / (m 2 ·d), 0.05g / (m 2 ·d), 0.08g / (m 2 ·d), 0.1g / (m 2 ·d), 0.12g / (m 2 ·d), 0.15g / (m 2·d), 0.18g / (m 2 ·d), 0.2g / (m 2 ·d), 0.3g / (m 2 ·d), 0.4g / (m 2 ·d), 0.5g / (m 2 ·d), 0.6g / (m 2 ·d), 0.7g / (m 2 ·d), 0.9g / (m 2 ·d), 1g / (m 2 ·d), 1.2g / (m 2 ·d), 1.5g / (m 2 ·d), 1.7g / (m 2 ·d), 2g / (m 2 ·d), 2.5g / (m 2 ·d), 3g / (m 2 ·d), 3.5g / (m 2 ·d), 4g / (m 2 ·d) etc. The water vapor transmission rate of the water-blocking layer 3 is greater than 4 g / (m 2 When ·d), the water-blocking effect of the water-blocking layer 3 cannot meet the reliability requirements of non-silver paste batteries. When the water vapor permeability of the water-blocking layer 3 is less than or equal to 4 g / (m²), 2 When ·d), the encapsulated photovoltaic modules can meet the EL test requirements for good products.

[0079] Furthermore, the water vapor permeability of the water-blocking layer 3 is less than or equal to 0.12 g / (m²). 2 ·d). In this way, within the 25-year service life of photovoltaic modules, the degradation of water resistance and aging performance caused by long-term exposure to air can be improved, ensuring the reliability of the electrodes on the modules during service.

[0080] Furthermore, in this embodiment, the water vapor permeability of the water-blocking layer 3 is less than or equal to 0.03 g / (m²). 2 ·d), specifically 0.002 g / (m 2 ·d), 0.005g / (m 2 ·d), 0.008g / (m 2 ·d), 0.01g / (m 2 ·d), 0.012g / (m 2 ·d), 0.015g / (m 2 ·d), 0.018g / (m 2 ·d), 0.02g / (m 2 ·d), 0.022g / (m 2 ·d), 0.025g / (m 2·d), 0.028g / (m 2 ·d), 0.03g / (m 2 •d) etc. At this point, the manufactured photovoltaic modules have excellent water-blocking properties, and the electrode structure of the modules can operate reliably in high-humidity environments.

[0081] In some embodiments, the water-blocking layer 3 comprises butyl rubber, and the encapsulating film 4 comprises EVA (ethylene-vinyl acetate copolymer). In this case, the main component of the water-blocking layer 3 is butyl rubber, and other components are not specifically limited in this application.

[0082] When the above technical solution is adopted, the water-blocking layer 3, made of butyl rubber, can meet the requirement that the water vapor permeability is less than or equal to 0.03 g / (m²). 2 ·d), which is much smaller than the water vapor transmission rate of the encapsulating film 4 (5g / (m)). 2 ·d)-10g / (m 2 •d)) has excellent water-blocking effect. The encapsulating film 4 uses EVA combined with butyl rubber as the main material for the water-blocking layer 3. Both can be well bonded and fixed to the cover plate 6 and the back plate 7, improving the structural stability of the photovoltaic module and reducing the risk of delamination and peeling of the modules.

[0083] Of course, other materials with low water vapor permeability can also be used for the water barrier layer 3, which will not be listed here.

[0084] In some embodiments, the size of the water-blocking layer 3 is less than or equal to 0.1 times the size of the encapsulating film 4 in the direction from the water-blocking layer 3 to the encapsulating film 4. The water-blocking layer 3, which has a water-blocking effect, often has low light transmittance; this design minimizes the adverse effects on the light absorption rate of the component. For example, the size of the water-blocking layer 3 is 0.05, 0.06, 0.07, 0.08, 0.09, or 0.1 times the size of the encapsulating film 4. As shown in Figures 1 and 2, in some possible implementations, the water-blocking layer 3 is located between the cover plate 6 and the back plate 7, i.e., the water-blocking layer 3 is sandwiched between the cover plate 6 and the back plate 7. When the water-blocking layer 3 is made of butyl rubber, the butyl rubber fills the space between the cover plate 6 and the back plate 7. The encapsulating film 4 covers the surface of the batteries included in the battery pack 5, that is, the front of the battery between the cover plate 6, the back of the battery between the back plate 7 and the side of the battery. All the batteries in the battery pack are encapsulated in the encapsulating film 4. The encapsulating film 4 is also present between the battery and the water-blocking layer 3.

[0085] With the above technical solution, the water-blocking layer 3 is located between the cover plate 6 and the back plate 7. While achieving the same water-blocking and sealing effect, the side length of the photovoltaic module can be reduced. Furthermore, for the butyl rubber, being located between the cover plate 6 and the back plate 7 provides a more stable filling space, improving the fixing and sealing effect between the butyl rubber and the cover plate 6 and the back plate 7. Simultaneously, the butyl rubber can also prevent the encapsulating film 4 from flowing out. The encapsulating film 4 covers the surface of all the cells in the battery pack 5, improving the buffering, fixing, and insulation effect on the cells. In addition, it can provide a certain degree of water-blocking sealing for the cells from all directions. Moreover, the encapsulating film 4 separates the cells from the water-blocking layer 3, reducing the risk of edge fragmentation and microcracks caused by direct contact between the relatively hard butyl rubber water-blocking layer 3 and the cells.

[0086] In some embodiments, when the water-blocking layer 3 is located between the cover plate 6 and the back plate 7, the water-blocking layer 3 is in contact with the encapsulating film 4, and the peel force between them is less than or equal to 5 N / cm, specifically 1 N / cm, 2 N / cm, 3 N / cm, 4 N / cm, 5 N / cm, etc. With the above technical solution, the water-blocking layer 3 and the encapsulating film 4 are mainly in simple contact or bonding, and there is no chemical fusion phenomenon such as cross-linking between them, with a peel force less than or equal to 5 N / cm. This can reduce the impact of the encapsulating film intruding into the water-blocking layer and affecting its water-blocking effect.

[0087] In some embodiments, there are gaps or pores between the water-blocking layer 3 and the encapsulating film 4. These gaps or pores prevent the encapsulating film 4 from intruding into the water-blocking layer 3 and affecting its water-blocking effect. They also prevent the water-blocking layer 3 (such as butyl rubber) from extending onto the battery, obstructing its path, and affecting power generation efficiency. Of course, transparent butyl rubber can be selected.

[0088] For example, when butyl rubber is used for the water-blocking layer 3, in order to prevent cross-linking between the butyl rubber and the encapsulation film 4 and to prevent the encapsulation film 4 from intruding into the water-blocking layer 3, the diffusion of butyl rubber during lamination needs to be considered during preparation. Butyl rubber diffuses 20%-25% after lamination, and the creepage distance from the battery to the edge of the cover plate is generally 13mm-14mm. Therefore, the width d of the butyl rubber during preparation must satisfy: d·1.25 ≤ creepage distance, and the width of the encapsulation film must satisfy: battery pack width ≤ encapsulation film width ≤ cover plate width - 2·(d·1.25); where 1.25 is the elongation coefficient of butyl rubber. In this way, after the butyl rubber diffuses during lamination, it will not diffuse onto the battery and will only have simple contact with the encapsulation film or have gaps or pores.

[0089] In some embodiments, the melting point of the water-blocking layer 3 is lower than that of the encapsulating film 4. Thus, during the photovoltaic module manufacturing process, the water-blocking layer 3 melts upon heating and adheres to the cover plate 6 and the back plate 7, achieving a good bond and seal. This prevents the encapsulating film 4 from melting first and then flowing out into the gaps between the unmelted water-blocking layer 3 and the cover plate 6 and / or the back plate 7. It effectively seals the encapsulating film 4 and prevents it from melting first and then intruding into the water-blocking layer 3 and between the water-blocking layer 3 and the cover plate 6 and back plate 7, thus affecting the water-blocking performance of the water-blocking layer 3. This ensures the water-blocking and sealing effect of the water-blocking layer 3 and the photovoltaic module.

[0090] In some embodiments, when the water-blocking layer 3 is located between the cover plate 6 and the back plate 7, in the width direction of the water-blocking layer 3 (i.e., from left to right in FIG1), more than 70% of the width area of ​​the water-blocking layer 3 from the outside to the inside is in direct contact with the cover plate 6 and / or the back plate 7. Specifically, the width area can be 70%, 75%, 80%, 85%, 90%, 95%, 100%, etc. With this configuration, the width of the area in direct contact between the water-blocking layer 3 and the cover plate 6 and / or back plate 7 is more than 70% from the outside to the inside. This means that the area between the water-blocking layer 3 and the cover plate 6 and / or back plate 7 where the encapsulating film 4 has penetrated is small or nonexistent. Furthermore, the encapsulating film 4 only penetrates the inner part of the water-blocking layer 3, while the outer part is not penetrated by the encapsulating film 4. This reduces the impact of the encapsulating film 4 on the water-blocking effect of the water-blocking layer 3 and ensures the sealing and bonding effect between the water-blocking layer 3 and the cover plate 6 and / or back plate 7, reducing the risk of moisture entering the photovoltaic module through the gap between the water-blocking layer 3 and the cover plate 6 and / or back plate 7.

[0091] For example, when the water-blocking layer 3 is made of butyl rubber, in order to avoid or reduce the intrusion of the encapsulating film 4 between the butyl rubber and the cover plate 6 and / or the back plate 7, the butyl rubber needs to be able to support the gap between the cover plate 6 and the back plate 7. Considering the extensibility of the butyl rubber during lamination, the thickness of the butyl rubber is ≥ 2 times the thickness of the encapsulating film + the thickness of the battery pack during preparation, so that the butyl rubber can fully contact the cover plate 6 and the back plate 7, reduce the existence of gaps, and prevent the encapsulating film 4 from intruding into the gaps and affecting the water-blocking and sealing effect.

[0092] In some embodiments, when the water-blocking layer 3 is located between the cover plate 6 and the back plate 7, the overlap width between the projection of the water-blocking layer 3 on the cover plate 6 and the projection of the encapsulating film 4 on the cover plate 6 is 0mm-1mm; the overlap width between the projection of the water-blocking layer 3 on the back plate 7 and the projection of the encapsulating film 4 on the back plate 7 is also 0mm-1mm. The specific overlap width can be 0mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1mm, etc. Thus, the area intruded by the encapsulating film 4 between the water-blocking layer 3 and the cover plate 6 and back plate 7 is small, reducing the impact of the encapsulating film 4 on the water-blocking effect of the water-blocking layer 3 and ensuring the overall water-blocking and sealing effect of the photovoltaic module.

[0093] In some embodiments, when the water-blocking layer 3 is located between the cover plate 6 and the back plate 7, the width of the water-blocking layer 3 is 3mm-16mm, specifically 3mm, 5mm, 7mm, 9mm, 11mm, 13mm, 16mm, etc. If the width of the water-blocking layer 3 is less than 3mm, the width of the water-blocking layer 3 is too small, and the water-blocking and sealing effect is not ideal. If the width of the water-blocking layer 3 is greater than 16mm, the width of the water-blocking layer 3 is too wide, occupying too much width at the edge of the photovoltaic module, increasing the size of the photovoltaic module or reducing the power generation efficiency per unit area of ​​the cell, and increasing the material cost of the water-blocking layer 3.

[0094] In some embodiments, the difference between the width of the water-blocking layer 3 at the first position and the width at the second position is less than or equal to 40% of the larger of the two widths. Specifically, the difference in width between any two positions of the water-blocking layer 3 is less than or equal to 40% of the larger of the two widths. This can be 0%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, etc. With this configuration, the overall width of the water-blocking layer 3 is more uniform, the water-blocking effect at all edges of the photovoltaic module is more balanced, the required material weight is basically consistent, and the weight uniformity at all edges of the photovoltaic module is improved.

[0095] In some possible implementations, the water-blocking layer 3 is bonded to both the cover plate 6 and the back plate 7. For example, the water-blocking layer 3 can be made of butyl rubber, which is then bonded and sealed to both the cover plate 6 and the back plate 7. Furthermore, there are no holes with a diameter greater than or equal to 0.5 mm between the water-blocking layer 3 and the cover plate 6 and the back plate 7, and the water-blocking layer 3 itself has no holes with a diameter greater than or equal to 0.5 mm. This configuration, with no holes or very small holes between the water-blocking layer 3 and the cover plate 6 and the back plate 7, as well as within the water-blocking layer 3 itself, improves the sealing and bonding effect between the water-blocking layer 3 and the cover plate 6 and the back plate 7, and also enhances the water-blocking and sealing effect of the water-blocking layer 3 itself, thereby improving the water-blocking and sealing performance of the photovoltaic module. When holes are present, their diameter can be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, etc.

[0096] In some embodiments, when the water-blocking layer 3 is located between the cover plate 6 and the back plate 7, the adhesive force between the water-blocking layer 3 and the cover plate 6 is greater than the adhesive force between the encapsulating film 4 and the cover plate 6. The adhesive force between the water-blocking layer 3 and the back plate 7 is also greater than the adhesive force between the encapsulating film 4 and the back plate 7. Thus, the greater adhesive force between the water-blocking layer 3 and the cover plate 6 and the back plate 7 improves the sealing effect between the upper and lower interfaces of the water-blocking layer 3 and the cover plate 6 and the back plate 7, making it less likely for the encapsulating film 4 to leak out, thereby improving the water-blocking performance.

[0097] In some embodiments, the peel force between the water-blocking layer 3 and the cover plate 6 and the back plate 7 is greater than or equal to 200 N / cm, specifically 200 N / cm, 250 N / cm, 300 N / cm, 350 N / cm, 400 N / cm, etc. This reduces the likelihood of detachment during use and transportation, improving sealing and water-blocking performance and structural reliability.

[0098] In some embodiments, the hardness of the water-blocking layer 3 is greater than the hardness of the encapsulating film 4. In this case, the water-blocking layer 3, located on the outside of the encapsulating film 4, can provide better support performance.

[0099] As shown in Figures 1 and 2, in some embodiments, the water-blocking layer 3 is disposed around the perimeter between the cover plate 6 and the back plate 7, and the encapsulating film 4 is disposed between the cover plate 6 and the back plate 7 within the area enclosed by the water-blocking layer 3. That is, the water-blocking layer 3 is disposed around the perimeter between the cover plate 6 and the back plate 7, forming a closed, sealed water-blocking space. This arrangement, with the water-blocking layer 3 disposed around the perimeter between the cover plate 6 and the back plate 7, and the encapsulating film 4 surrounded within the area enclosed by the water-blocking layer 3, improves the water-blocking and sealing performance around the photovoltaic module. Of course, the water-blocking layer 3 can also be disposed in a localized area corresponding to the battery location at the edge between the cover plate 6 and the back plate 7, providing water-blocking treatment for key areas requiring waterproofing.

[0100] In some possible implementations, the photovoltaic module also includes a water-blocking reinforcement layer (not shown in the figure); the water vapor transmission rate of the water-blocking reinforcement layer is lower than that of the water-blocking layer 3, and the water-blocking reinforcement layer is disposed at least at one of the following three locations: between the water-blocking layer 3 and the cover plate 6, between the water-blocking layer 3 and the back sheet 7, and on the side of the water-blocking layer 3 facing away from the battery pack 5. The water-blocking reinforcement layer can be made of a material with low water vapor transmission rate, similar to butyl rubber. The water-blocking performance of the photovoltaic module is further improved by providing the water-blocking reinforcement layer. For example, when the water-blocking reinforcement layer is disposed between the water-blocking layer 3 and the cover plate 6, between the water-blocking layer 3 and the back sheet 7, and on the side of the water-blocking layer 3 facing away from the battery pack 5, the water-blocking reinforcement layer surrounds the water-blocking layer 3 on three sides, forming a water-blocking structure, further improving the water-blocking and sealing performance.

[0101] In some possible implementations, the back panel 7 has outlet holes for bringing out conductive interconnects (such as busbars, leads, etc.) within the assembly, connecting them to the junction box to conduct current. A water-blocking structure is also provided at the outlet holes, with the difference in water vapor permeability between the water-blocking structure and the water-blocking layer 3 being less than 0.5 g / (m²). 2 ·d), specifically 0g / (m 2 ·d), 0.01g / (m 2 ·d), 0.05g / (m 2 ·d), 0.1g / (m 2 ·d), 0.2g / (m 2·d), 0.4g / (m 2 ·d), 0.5g / (m 2 •d) etc. For example, the water-blocking structure for the lead-out holes can be butyl rubber, which fills the lead-out holes and the area between the junction box and the backsheet. In addition to setting water-blocking structures at the edges of the photovoltaic modules, water-blocking structures are also set at the lead-out holes on the backsheet. The water-blocking effect of the water-blocking structure is similar to that of the water-blocking layer 3, reducing the risk of moisture entering the module through the lead-out holes, thereby improving the overall sealing and water-blocking performance of the module.

[0102] As shown in Figures 1 and 2, in some embodiments, when the water-blocking layer 3 is located between the cover plate 6 and the back plate 7, the outer edge of the water-blocking layer 3 is flush with the outer edges of the cover plate 6 and the back plate 7.

[0103] With the above technical solution, the outer edge of the water-blocking layer 3 is flush with the outer edges of the cover plate 6 and the back plate 7, which can fill the edge space between the cover plate 6 and the back plate 7 to the greatest extent, so as to make full use of the edge area between the cover plate 6 and the back plate 7 for water-blocking and sealing. Moreover, the flush setting, compared with the concave setting, is conducive to the smooth bonding and fixing between the frame and the outer edges of the cover plate 6, the water-blocking layer 3 and the back plate 7, reducing the gaps caused by the positional difference between the water-blocking layer 3 and the edges of the cover plate 6 and the back plate 7, thereby improving the sealing effect. The frame 1 is bonded and fixed to the edge of the component by the auxiliary water-blocking layer 2.

[0104] In some embodiments, the outer edge of the water-blocking layer 3 protrudes beyond the outer edge of the cover plate 6. This ensures that the water-blocking layer 3 has sufficient width and facilitates the coating and excess adhesive effect between the cover plate 6, the water-blocking layer 3, the back plate 7, and the frame.

[0105] As shown in Figure 2, in some embodiments, in addition to the water-blocking layer 3 being located between the cover plate 6 and the back plate 7, the photovoltaic module in this embodiment also includes an end water-blocking tape 8. The end water-blocking tape 8 is disposed on the outer periphery of the cover plate 6 and the back plate 7. The water vapor transmission rate of the end water-blocking tape 8 is greater than that of the water-blocking layer 3 but less than that of the encapsulating film. With this arrangement, by wrapping and adhering the end water-blocking tape 8 to the outer periphery of the cover plate 6, the back plate 7, and the water-blocking layer 3, the water vapor transmission performance of the water-blocking structure composed of the end water-blocking tape 8, the water-blocking layer 3, and the encapsulating film 4 from the outside to the inside changes in a stepped, non-linear manner, which can further improve the water-blocking and sealing performance.

[0106] For example, the end-blocking tape 8 can be an aluminum foil tape. Aluminum foil tape is typically a tape containing an aluminum layer. The water vapor transmission rate of the aluminum foil tape is less than or equal to 0.1 g / (m²). 2•d) The cross-section of the aluminum foil tape can be C-shaped. Both ends of the aluminum foil tape are respectively adhered to the upper edge of the cover plate 6 and the lower edge of the back plate 7, while the middle portion is adhered to the side of the stacked cover plate 6, water-blocking layer 3, and back plate 7. The adhesive force between the aluminum foil tape and the cover plate 6 and back plate 7 is greater than or equal to 5 N / cm, ensuring a firm bond. The width of the end of the aluminum foil tape adhered to the cover plate is greater than or equal to 3 mm to guarantee a strong bond.

[0107] In some embodiments, the photovoltaic module further includes a frame and an auxiliary water-blocking layer. The frame is fixedly disposed on the outer periphery of the cover plate and the back plate through the auxiliary water-blocking layer. Along the side of the frame to the center of the battery pack, the auxiliary water-blocking layer, the water-blocking layer and the encapsulating film are disposed sequentially, and the water vapor permeability of the three decreases first and then increases. The water vapor permeability of the encapsulating film is less than that of the auxiliary water-blocking layer.

[0108] For example, a frame 1 surrounds the outer periphery of the cover plate 6 and the back plate 7. The frame 1 has a slot and surrounds the edge of the laminate composed of the cover plate 6, the back plate 7, the battery pack 5, the encapsulating film 4, the water-blocking layer 3, and the auxiliary water-blocking layer 2 through the slot. The frame 1 includes an A-side, a B-side, and a C-side. The A-side is the top of the frame 1, the B-side is the side of the frame 1, and the C-side is the bottom of the frame 1. The A-side and the C-side are connected through the B-side. The A-side is disposed on the surface edge of the cover plate 6, and the B-side is disposed opposite to the outer peripheral side of the cover plate 6 and the back plate 7. Along the direction from the B-side of the frame 1 to the center of the battery pack 5, the auxiliary water-blocking layer 2, the water-blocking layer 3, and the encapsulating film 4 are arranged sequentially between the B-side of the frame 1 and the edge of the battery pack 5. The water vapor transmission rate of the water-blocking layer 3 is less than that of the auxiliary water-blocking layer 2 and the encapsulating film 4. For example, the auxiliary water-blocking layer 2 has a C-shaped cross-section and covers the surface edges and sides of the cover plate 6, the water-blocking layer 3, and the back plate 7. The C-shaped auxiliary water-blocking layer 2 can seal the upper and lower surfaces and sides of the photovoltaic module, improving the sealing and water-blocking performance, and also improving the reliability and sealing of the bonding and fixing of the auxiliary water-blocking layer 2 to the frame 1. Of course, the cross-sectional shape of the auxiliary water-blocking layer 2 can also be other shapes, such as L-shaped, I-shaped, etc., that is, covering only the sides, or covering the upper surface and three sides of the cover plate 6, or covering the lower surface and three sides of the back plate, as long as it can be bonded to the frame 1 and serve as a water-blocking structure.

[0109] Between the B-side of the frame 1 and the battery pack 5, an auxiliary water-blocking layer 2, a water-blocking layer 3, and an encapsulating film 4 are sequentially arranged. From the outside to the inside, the water vapor permeability first decreases and then increases. The lower the water vapor permeability, the better the water-blocking effect. Compared with existing photovoltaic modules, the edge of the photovoltaic module in this application is sealed with a three-layer structure for water blocking. Among them, the water-blocking layer 3 has the lowest water vapor permeability and the best water blocking effect. First, the auxiliary water-blocking layer 2 located on the outer layer blocks some water vapor from passing through. Then, the water-blocking layer 3 with the lowest water vapor permeability achieves the main water blocking effect. Finally, the innermost encapsulating film 4 is used for water blocking and sealing, which improves the water blocking effect and can effectively prevent water vapor from penetrating into the interior of the photovoltaic module. This reduces the impact on the performance of non-pure silver paste electrodes, ensures the reliability of the electrodes on the battery cells, and achieves the goal of cost reduction.

[0110] In some embodiments, the auxiliary water-blocking layer 2 includes silicone. The auxiliary water-blocking layer 2 uses silicone, and the frame 1 can be bonded and sealed around the edge of the photovoltaic module using silicone, while also providing a certain degree of water-blocking effect. The water vapor transmission rate of the auxiliary water-blocking layer 2 is greater than that of the encapsulating film 4, effectively blocking some water vapor from passing through in the three-layer water-blocking structure, thus improving the water-blocking effect.

[0111] In some embodiments, as shown in Figures 1 and 2, the orthographic projection of the frame 1 covers the orthographic projection of the water-blocking layer 3 in the direction of the vertical upper surface of the cover plate 6. This configuration allows the water-blocking layer 3, which is opaque in color such as black or gray, to be shielded by the A-side (top surface) of the frame 1, improving the appearance of the photovoltaic module.

[0112] In some embodiments, an auxiliary water-blocking layer covers the outer side of the water-blocking layer. One side of the auxiliary water-blocking layer 2 is bonded and fixed to the frame 1, and the other side is bonded and fixed to the outer edge of the stacked cover plate 6, water-blocking layer 3 and back plate 7, which can protect the water-blocking layer.

[0113] In some embodiments, an end-water-blocking tape is provided between the auxiliary water-blocking layer and the side of the cover plate. In this case, the auxiliary water-blocking layer, the end-water-blocking tape, and the encapsulating film work together to improve the water-blocking performance while facilitating the repair of the end-water-blocking tape.

[0114] When the cross-section of the auxiliary water-blocking layer 2 is C-shaped, the width of the two ends of the auxiliary water-blocking layer 2 covering the cover plate 6 and the back plate 7 is greater than the width of the aluminum foil tape adhered to the cover plate 6 and the back plate 7. That is, the width of the slot of the frame 1 is greater than the width of the aluminum foil tape adhered to the cover plate 6, so that the frame 1 is adhered to the cover plate 6 and the back plate 7 through the auxiliary water-blocking layer 2, avoiding the slot of the frame 1 being only adhered to the aluminum foil tape, thus preventing the frame from falling off.

[0115] As shown in Figure 3, in some possible implementations, another water-blocking layer 3 is provided. This water-blocking layer 3 is located outside the cover plate 6 and the back plate 7, and is not disposed between the cover plate 6 and the back plate 7. The cross-section of the water-blocking layer 3 is C-shaped. The water-blocking layer 3 is aluminum foil tape. Thus, the C-shaped water-blocking layer 3 wraps around the outside of the cover plate 6 and the back plate 7. The water-blocking layer 3 is made of aluminum foil tape, with both ends of the aluminum foil tape bonded to the upper surface edge of the cover plate 6 and the lower surface edge of the back plate 7, respectively. The middle part of the aluminum foil tape is bonded to the side of the stacked cover plate 6, water-blocking layer 3, and back plate 7. The aluminum foil tape is separated from the edge of the battery pack 5 by an encapsulating film 4. The water vapor transmission rate of the aluminum foil tape is less than or equal to 0.1 g / m³. 2 The water vapor transmission rate (d) is much smaller than that of the encapsulating film 4. The water-blocking layer 3 of this structure also improves water-blocking and sealing performance. Furthermore, since the water-blocking layer 3 is located on the outside of the cover plate 6 and the back plate 7, it reduces the space occupied between the cover plate 6 and the back plate 7, increases the area ratio of the battery pack 5, and improves the power generation efficiency per unit area of ​​the photovoltaic module.

[0116] Of course, the cross-section of the aluminum foil tape can also be L-shaped, I-shaped, etc., that is, the aluminum foil tape covers the upper surface edge of the cover plate 6 and the side of the laminate, or the aluminum foil tape covers the lower surface edge of the back plate 7 and the side of the laminate, or the aluminum foil tape covers the side of the laminate, as long as it can prevent moisture from entering between the cover plate 6 and the back plate 7.

[0117] As shown in Figure 3, in some embodiments, when the water-blocking layer 3 is disposed on the outside of the cover plate 6 and the back plate 7, and the outside of the water-blocking layer is fixed to the frame by an auxiliary water-blocking layer, the cross-sectional shape of the auxiliary water-blocking layer 2 is C-shaped on a cross-section parallel to the thickness direction of the photovoltaic module and perpendicular to one side of the photovoltaic module. The middle part of the auxiliary water-blocking layer 2 is bonded to the water-blocking layer 3, and the two ends of the auxiliary water-blocking layer 2 are bonded to the cover plate 6 and the back plate 7, respectively. Thus, with the water-blocking layer 3 located outside the cover plate 6 and back plate 7, the auxiliary water-blocking layer 2, in a C-shape, wraps around the outside of the water-blocking layer 3. Both ends of the auxiliary water-blocking layer 2 are adhered to at least the cover plate 6 and back plate 7. That is, while the ends of the auxiliary water-blocking layer 2 are adhered to the cover plate 6 and back plate 7, they can also be adhered to the ends of the C-shaped water-blocking layer 3. Since the adhesive force of the auxiliary water-blocking layer 2 (such as silicone to aluminum foil tape) is less than the adhesive force of silicone to the cover plate 6 and back plate 7, adhering the silicone to at least the cover plate 6 and back plate 7 prevents the frame from detaching. The auxiliary water-blocking layer 2 improves the fixation effect of the water-blocking layer 3 outside the cover plate 6 and back plate 7, making it less prone to detachment.

[0118] In some embodiments, when the water-blocking layer 3 is disposed on the outside of the cover plate 6 and the back plate 7, and the frame 1 is fixed to the outside of the water-blocking layer 3 by the auxiliary water-blocking layer 2, the width of the auxiliary water-blocking layer 2 bonded to the cover plate 6 is 5mm-10mm. Specifically, it can be 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc. In this case, the width of the auxiliary water-blocking layer 2 covering the cover plate 6 is greater than the width of the bond between the water-blocking layer 3 and the cover plate 6. At this time, it can be ensured that the auxiliary water-blocking layer 2, which has the functions of installation and water blocking, has sufficient fixing width and bonding area with the cover plate 6 and the back plate 7, thereby reducing the risk of the auxiliary water-blocking layer 2 and the frame 1 falling off. If the width of the auxiliary water-blocking layer 2 bonded to the cover plate 6 is less than 5mm, the bonding effect between the auxiliary water-blocking layer 2 and the cover plate 6 and the fixing effect of the frame 1 are not good. If the width is greater than 10mm, it increases the obstruction of the light-receiving area of ​​the battery by the auxiliary water-blocking layer 2 and increases the material cost.

[0119] In some embodiments, when the water-blocking layer 3 is disposed on the outside of the cover plate 6 and the back plate 7, the bonding width between the water-blocking layer 3 and the front of the cover plate 6 and the back of the back plate 7 is 2mm-5mm, specifically 2mm, 3mm, 4mm, 5mm, etc. The bonding width of the water-blocking layer 3 on the front of the cover plate 6 and the bonding width of the water-blocking layer 3 on the back of the back plate 7 can be the same or different. When the width is the same, the adhesive force at both ends of the water-blocking layer 3 can be more balanced. When the width is different, the bonding width between the water-blocking layer 3 and the back plate 7 can be wider, improving the bonding firmness, while not affecting the light reception on the front. Furthermore, with the above-mentioned bonding width, the water-blocking layer 3 can better cover the sides of the cover plate 6 and the back plate 7 and bond and fix them to both. When the width of the bonding between the water-blocking layer 3 and the front of the cover plate 6 and / or the back of the back plate 7 is less than 2mm, the bonding width of the water-blocking layer 3 is too small, and the fixing effect of the water-blocking layer 3 is not good. When the width is greater than 5mm, it is easy to block the light-receiving area of ​​the battery and affect the bonding effect between the auxiliary water-blocking layer 2 and the cover plate 6 and the back plate 7, which increases the material cost.

[0120] In some embodiments, when the water-blocking layer 3 is disposed on the outer side of the cover plate 6 and the back plate 7, the adhesive force between the water-blocking layer 3 and the cover plate 6 and the back plate 7 is greater than or equal to 5 N / cm. Specifically, the adhesive force can be 5 N / cm, 10 N / cm, 20 N / cm, 30 N / cm, 40 N / cm, etc. With the above technical solution, the adhesive force between the water-blocking layer 3 and the cover plate 6 and the back plate 7, which is greater than or equal to 5 N / cm, ensures good bonding and fixing performance.

[0121] For example, when the water-blocking layer 3 is aluminum foil tape, the width of the aluminum foil tape cut during preparation needs to meet the following requirements: aluminum foil tape cutting width > cover plate thickness + back plate thickness + aluminum foil tape bonding width with cover plate + aluminum foil tape bonding width with back plate, and aluminum foil tape cutting width < frame slot width 2 + cover plate thickness + back plate thickness. If the aluminum foil tape cutting width is large, the frame 1 will directly contact the aluminum foil tape and not contact the cover plate 6 and back plate 7, which may cause risks such as frame detachment.

[0122] Based on the photovoltaic modules described in any of the above embodiments, this application also provides a photovoltaic system including the photovoltaic modules described in any of the above embodiments. Since the photovoltaic system uses the photovoltaic modules in the above embodiments, the photovoltaic system has the same beneficial effects as the photovoltaic modules, and will not be described in detail.

[0123] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0124] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A photovoltaic module, wherein, include: The cover and back plate are set opposite each other; The battery pack is disposed between the cover plate and the back plate; The battery pack is fixed to the cover plate and the back plate by the encapsulation film; And a water-blocking layer, disposed on the outside of the encapsulating film; Wherein, the water vapor transmission rate of the water-blocking layer is less than that of the encapsulating film, and the size of the water-blocking layer is smaller than that of the encapsulating film in the direction from the water-blocking layer to the encapsulating film.

2. The photovoltaic module according to claim 1, wherein, The water vapor permeability of the water-blocking layer is less than or equal to 0.12 g / (m²). 2 ·d).

3. The photovoltaic module according to claim 1, wherein, The water-blocking layer must meet at least one of the following conditions: A. The water vapor permeability of the water-blocking layer is less than or equal to 0.03 g / (m²). 2 ·d); B. The water-blocking layer comprises butyl rubber, and the encapsulating film comprises EVA; C. In the direction from the water-blocking layer to the encapsulating film, the size of the water-blocking layer is less than or equal to 0.1 times the size of the encapsulating film.

4. The photovoltaic module according to claim 1, wherein, The water-blocking layer is located between the cover plate and the back plate, the encapsulating film wraps the surface of the battery included in the battery pack, and the encapsulating film is present between the battery and the water-blocking layer.

5. The photovoltaic module according to claim 1, wherein, The water-blocking layer is located between the cover plate and the back plate; the water-blocking layer and the encapsulating film satisfy at least one of the following conditions: D. The water-blocking layer and the encapsulating film are in contact, and the peel force between them is less than or equal to 5 N / cm; E. There are gaps or holes between the water-blocking layer and the encapsulating film.

6. The photovoltaic module according to claim 1, wherein, The melting point of the water-blocking layer is lower than that of the encapsulating film.

7. The photovoltaic module according to any one of claims 1-6, wherein, The water-blocking layer is located between the cover plate and the back plate. In the width direction of the water-blocking layer, more than 70% of the width area of ​​the water-blocking layer from the outside to the inside is in direct contact with the cover plate and / or the back plate.

8. The photovoltaic module according to any one of claims 1-6, wherein, The water-blocking layer is located between the cover plate and the back plate; The overlap width between the orthographic projection of the water-blocking layer on the cover plate and the orthographic projection of the encapsulating film on the cover plate is 0mm-1mm; the overlap width between the orthographic projection of the water-blocking layer on the back plate and the orthographic projection of the encapsulating film on the back plate is 0mm-1mm.

9. The photovoltaic module according to any one of claims 1-6, wherein, The water-blocking layer is located between the cover plate and the back plate; the water-blocking layer satisfies at least one of the following conditions: F. The width of the water-blocking layer is 3mm-16mm; G. The difference between the width of the first position and the width of the second position of the water-blocking layer is less than or equal to 40% of the larger of the two widths.

10. The photovoltaic module according to any one of claims 1-6, wherein, The water-blocking layer is located between the cover plate and the back plate; the water-blocking layer is bonded to both the cover plate and the back plate, and there are no holes with a diameter greater than or equal to 0.5 mm between the water-blocking layer and the cover plate and the back plate, and the water-blocking layer has no holes with a diameter greater than or equal to 0.5 mm.

11. The photovoltaic module according to any one of claims 1-6, wherein, The water-blocking layer must meet at least one of the following conditions: H. The water-blocking layer is located between the cover plate and the back plate; the adhesive force between the water-blocking layer and the cover plate is greater than the adhesive force between the encapsulating film and the cover plate; the adhesive force between the water-blocking layer and the back plate is greater than the adhesive force between the encapsulating film and the back plate; I. The water-blocking layer is located between the cover plate and the back plate, and the peel force between the water-blocking layer and the cover plate and the back plate is greater than or equal to 200 N / cm; J. The hardness of the water-blocking layer is greater than the hardness of the encapsulating film.

12. The photovoltaic module according to any one of claims 1-6, wherein, The water-blocking layer is disposed in the surrounding area between the cover plate and the back plate, and the encapsulating film is disposed between the cover plate and the back plate and located within the area enclosed by the water-blocking layer.

13. The photovoltaic module according to claim 12, wherein, The photovoltaic module further includes a water-blocking reinforcement layer; the water vapor transmission rate of the water-blocking reinforcement layer is less than that of the water-blocking layer, and the water-blocking reinforcement layer is disposed at least at one of the following three locations: between the water-blocking layer and the cover plate, between the water-blocking layer and the back plate, and on the side of the water-blocking layer away from the battery pack.

14. The photovoltaic module according to claim 12, wherein, The outer edge of the water-blocking layer is flush with the outer edge of the cover plate, or the outer edge of the water-blocking layer protrudes from the outer edge of the cover plate.

15. The photovoltaic module according to claim 12, wherein, The outer periphery of the cover plate and the back plate is further provided with end water-blocking tape, the water vapor transmission rate of the end water-blocking tape is greater than the water vapor transmission rate of the water-blocking layer, and less than the water vapor transmission rate of the encapsulating film.

16. The photovoltaic module according to claim 1, wherein, The back plate has outlet holes, and a water-blocking structure is also provided at the outlet holes. The difference in water vapor permeability between the water-blocking structure and the water-blocking layer is less than 0.5 g / (m²). 2 ·d).

17. The photovoltaic module according to any one of claims 1-6, wherein, The photovoltaic module also includes a frame and an auxiliary water-blocking layer. The frame is fixed to the outer periphery of the cover plate and the back plate by the auxiliary water-blocking layer. Along the side of the frame to the center of the battery pack, the auxiliary water-blocking layer, the water-blocking layer and the encapsulation film are arranged in sequence, and the water vapor permeability of the three decreases first and then increases. The water vapor permeability of the encapsulation film is less than that of the auxiliary water-blocking layer.

18. The photovoltaic module according to claim 17, wherein, The photovoltaic module must meet at least one of the following conditions: K. In the direction perpendicular to the upper surface of the cover plate, the orthographic projection of the frame overlaps the orthographic projection of the water-blocking layer; L. The auxiliary water-blocking layer covers the outer surface of the water-blocking layer; M. An end-water-blocking tape is provided between the auxiliary water-blocking layer and the side of the cover plate.

19. The photovoltaic module according to claim 1, wherein, The water-blocking layer is located on the outside of the cover plate and the back plate; the water-blocking layer satisfies at least one of the following conditions: N. The cross-section of the water-blocking layer is C-shaped; O. The water-blocking layer is aluminum foil tape.

20. The photovoltaic module according to claim 17, wherein, The outer side of the water-blocking layer is fixed to the frame by the auxiliary water-blocking layer. On a cross-section parallel to the thickness direction of the photovoltaic module and perpendicular to one side of the photovoltaic module, the cross-sectional shape of the auxiliary water-blocking layer is C-shaped, and the middle part of the auxiliary water-blocking layer is bonded to the water-blocking layer. The auxiliary water-blocking layer satisfies at least one of the following conditions: P. The two ends of the auxiliary water-blocking layer are respectively bonded to the cover plate and the back plate; Q. The width of the auxiliary water-blocking layer bonded to the cover plate is 5mm-10mm.

21. The photovoltaic module according to claim 19, wherein, The water-blocking layer must meet at least one of the following conditions: R. The width of the water-blocking layer bonded to the front of the cover plate and the back of the back plate is 2mm-5mm; S. The adhesion force between the water-blocking layer and the cover plate and the back plate is greater than or equal to 5 N / cm.

22. A photovoltaic system, wherein, Includes the photovoltaic module as described in any one of claims 1-21.

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