Photovoltaic module

Abstract

The utility model discloses a photovoltaic assembly, which relates to the technical field of solar cell manufacturing and specifically comprises a cover plate, a cell array, a filling layer and a back plate. Wherein the cover plate and the back plate are stacked, and the lower main surface of the cover plate and the upper main surface of the back plate are fixedly connected and define one or more hollow cavities; the hollow cavity is used for placing a battery array; and the filling layer is filled in the hollow cavity and is used for sealing the battery array. According to the embodiment, the structures of the cover plate and the back plate are improved, so that after the cover plate and the back plate are stacked, the lower main surface of the cover plate and the upper main surface of the back plate can be in direct contact and define the hollow cavity for placing the battery array; the sealing performance of the side surface of the photovoltaic module is effectively improved, and the problems of water vapor erosion and delamination corrosion are avoided. And meanwhile, the battery array is sealed through the filling layer, so that the battery array is further protected.

Description

Technical Field

[0001] The utility model relates to the technical field of solar cell manufacturing, in particular to a photovoltaic component. Background Art

[0002] Existing photovoltaic modules typically stack a cover plate, front film, cell array, rear film, and back sheet, and then laminate them into an integrated structure through a lamination process. This laminated structure with exposed sides often suffers from performance issues such as poor resistance to moisture, susceptibility to yellowing due to aging, and susceptibility to delamination and corrosion. Utility Model Content

[0003] In light of this, embodiments of the present invention provide a photovoltaic module that improves the structure of the cover and backsheets. This allows the lower main surface of the cover and the upper main surface of the backsheet to directly contact each other when the cover and backsheets are stacked, forming a hollow cavity for housing the cell array. Compared to the prior art stacked structures with exposed side surfaces, this effectively improves the sealing of the photovoltaic module's sides, preventing moisture erosion and delamination corrosion. Furthermore, the cell array is sealed and further protected by the filler layer.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0005] In a first aspect, the utility model provides a photovoltaic module, comprising: a cover plate, a battery array, a filling layer and a back plate; wherein the cover plate and the back plate are stacked, and the lower main surface of the cover plate is fixedly connected to the upper main surface of the back plate and encloses one or more hollow cavities; the hollow cavity is used to place the battery array; the filling layer is filled in the hollow cavity to seal the battery array.

[0006] Optionally, one or more first grooves for placing battery strings in the battery array are provided on the lower main surface of the cover plate and / or the upper main surface of the back plate; the entire or partial structure of the hollow cavity is composed of the first grooves on the cover plate and / or the back plate.

[0007] Optionally, one or more second grooves for placing interconnecting strips in the battery array are further provided on the lower main surface of the cover plate and / or the upper main surface of the back plate; wherein the second grooves are cross-connected with the first grooves; and the second grooves are part of the hollow cavity.

[0008] Optionally, the depth of the hollow cavity is 200 μm to 600 μm.

[0009] Optionally, the filling material in the filling layer is at least one of epoxy resin, polyurethane, liquid silicone and silicone oil, and the refractive index of the filling layer is 1.5-2.5.

[0010] Optionally, it further includes: a lead-out hole provided on the upper main surface of the cover plate or the lower main surface of the back plate; the position of the lead-out hole corresponds to the second groove and is connected to the hollow cavity.

[0011] Optionally, the method further comprises: a packaging film disposed in the lead-out hole; the packaging film encapsulates the filling layer in the hollow cavity.

[0012] In a second aspect, the present invention provides a method for preparing a photovoltaic module, comprising:

[0013] Step 1: Lay out a back plate, a battery array, and a cover plate in sequence, so that the battery array is located in a hollow cavity formed between the cover plate and the back plate; the battery array may have a filling layer pre-cured on its surface or may not have a filling layer pre-cured on its surface;

[0014] Step 2: Welding the contact surfaces between the cover plate and the back plate in the area where the hollow cavity is not provided;

[0015] Wherein, if the filling layer is not pre-cured on the surface of the battery array, after step 2, the method further includes: step 3, if the filling layer is not pre-cured on the surface of the battery array, pouring a filling material into the hollow cavity and curing the filling material to form a filling layer that seals the battery array;

[0016] In the case where the battery array is a battery array with a filling layer pre-cured on the surface, before step 1, it also includes: step 0, in a vacuum environment, coating the filling material on the surface of the blank battery array, and obtaining the battery array with the filling layer pre-cured on the surface after curing.

[0017] The technical solution of the first aspect of the above-mentioned utility model has the following advantages or beneficial effects: By improving the structure of the cover plate and back plate, when the cover plate and back plate are stacked, the lower main surface of the cover plate and the upper main surface of the back plate can directly contact each other, thereby enclosing a hollow cavity for accommodating the battery array. Compared with the stacked structure with exposed sides in the prior art, this effectively improves the sealing of the photovoltaic module side, avoiding the problems of water vapor erosion and delamination corrosion. At the same time, the filling layer seals the battery array, further protecting the battery array. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are provided to facilitate a better understanding of the present invention and do not constitute an undue limitation of the present invention.

[0019] Figure 1 It is a schematic diagram of the structure of a photovoltaic module in the prior art;

[0020] Figure 2 is a schematic cross-sectional view of a photovoltaic assembly having a first groove only provided on the lower main surface of the cover plate according to an embodiment of the present utility model;

[0021] Figure 3 This is a schematic cross-sectional view of a photovoltaic module with first grooves symmetrically arranged on the cover plate and the back plate according to an embodiment of the present utility model;

[0022] Figure 4 is a schematic cross-sectional structural diagram of a photovoltaic module in which only a first groove is provided on the upper main surface of the back plate according to an embodiment of the present utility model;

[0023] Figure 5 1 is a schematic diagram of the planar structure of the first groove and the second groove according to an embodiment of the present utility model;

[0024] Figure 6 is a schematic cross-sectional structural diagram of a first groove according to an embodiment of the present utility model;

[0025] Figure 7 This is a structural diagram of an embodiment of the present invention in which the lead-out hole is arranged on the edge of the cover plate or the back plate;

[0026] Figure 8 This is a structural diagram of an embodiment of the present invention in which the lead-out hole is arranged in the middle area of ​​the cover plate or the back plate;

[0027] Figure 9 This is a schematic flow chart of a method for preparing a photovoltaic module according to an embodiment of the present utility model;

[0028] Figure 10 It is a specific flow chart of step S903 according to an embodiment of the present utility model.

[0029] The reference numerals are as follows:

[0030] 1-cover plate; 2-cell array; 3-filling layer; 4-back plate; 41-lead hole;

[0031] 100-hollow cavity; 200-first groove; 300-second groove. DETAILED DESCRIPTION

[0032] A solar cell is a photoelectric semiconductor wafer that uses sunlight to generate electricity directly. It is also called a "solar chip" or "photovoltaic cell." As long as it is illuminated by light that meets certain illumination conditions, it can instantly output voltage and generate current in the presence of a circuit. In physics, it is called solar photovoltaic (PV), or simply photovoltaic. In order to conveniently and clearly describe the method for preparing a solar cell and the solar cell of the present invention, the following exemplary embodiments of the present invention are described in conjunction with the accompanying drawings, including various details of the embodiments of the present invention to facilitate understanding. These should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0033] The photovoltaic module of the prior art is usually a cover plate 1, a front film, a battery array 2, a rear film and a back plate 4 are stacked and then laminated into an integrated structure through a lamination process, such as Figure 1 As shown. The multi-layered stacked structure leaves the sides of the front film, battery array 2, and rear film exposed. Although the photovoltaic module is provided with a frame and an encapsulating film filling the gap between the frame and the photovoltaic module, due to the material of the film itself, water vapor penetration can still occur under long-term water vapor erosion, causing the photovoltaic module to age, yellow, and even delamination and corrosion. Therefore, the present invention provides a new photovoltaic module structure that can effectively avoid the problem of exposed photovoltaic module sides and extend the service life of the photovoltaic module.

[0034] Figures 2 to 4 The cross-sectional structure diagram of the photovoltaic module provided by the embodiment of the present utility model is shown as follows: Figures 2 to 4 As shown, the photovoltaic module provided by the present invention includes: a cover plate 1, a battery array 2, a filling layer 3 and a back plate 4; wherein, the cover plate 1 and the back plate 4 are stacked, and the lower main surface of the cover plate 1 and the upper main surface of the back plate 4 are fixedly connected and enclose one or more hollow cavities 100; the hollow cavity 100 is used to place the battery array 2; the filling layer 3 is filled in the hollow cavity 100 to seal the battery array 2.

[0035] from Figure 2It can be seen that the embodiment of the present invention provides a hollow cavity 100 enclosed between the cover plate 1 and the back plate 4, which effectively protects the battery array 2 and the filling layer 3, avoiding the problem of directly exposing the filling layer 3 or the side of the battery array 2, and greatly improving the sealing of the photovoltaic module. Moreover, the direct contact between the cover plate 1 and the back plate 4 improves the overall mechanical strength of the photovoltaic module, effectively avoiding the deformation problem of the photovoltaic module. At the same time, compared to conventional filled cavity modules, the filling layer 3 in the embodiment of the present invention is not only used to seal the battery array, but also can avoid the problem of excessive temperature caused by poor heat transfer inside the cavity.

[0036] In an optional embodiment, one or more first grooves 200 for placing battery strings in the battery array 2 are provided on the lower main surface of the cover plate 1 and / or the upper main surface of the back plate 4; the first grooves 200 on the cover plate 1 and / or the back plate 4 constitute the entire or partial structure of the hollow cavity 100. It is understandable that the embodiment of the utility model forms a partial or complete cavity for placing battery strings in the battery array 2 through the first grooves 200. As to whether the first grooves 200 are provided on the cover plate 1, the back plate 4, or both the cover plate 1 and the back plate 4, it can be arranged according to needs. Specifically, the setting position of the hollow cavity 100 can be as follows: Figures 2 to 4 As shown, Figure 2 The first groove 200 is provided only on the lower main surface of the cover plate 1. Figure 3 The first groove 200 is symmetrically provided on the cover plate 1 and the back plate 4. Figure 4 The first groove 200 is only provided on the upper main surface of the back plate 4. Figures 2 to 4 It can be seen that when the first groove 200 is set at different positions, the position of the hollow cavity 100 will also change accordingly. In an optional embodiment, in order to relatively simplify the manufacturing process of the cover plate 1 and the back plate 4, it is preferred to adopt Figure 3 In this manner, first grooves 200 are provided on both the cover plate 1 and the back plate 4. This allows the cover plate 1 and the back plate 4 to be produced uniformly using the same layout. This means the produced glass assembly can serve as both the cover plate 1 and the back plate 4, eliminating the need for separate production of the cover plate 1 and the back plate 4. Furthermore, to ensure that the hollow cavity 100 can accommodate the battery array 2 without wasting excess space, in an optional embodiment, the depth of the hollow cavity 100 is between 200 μm and 600 μm, for example, 200 μm, 300 μm, 450 μm, 500 μm, 600 μm, and the like.

[0037] In addition to requiring a hollow area to accommodate the battery strings in the battery array 2, a portion of the hollow area is also required to accommodate the interconnection ribbons in the battery array 2. Therefore, in an optional embodiment, one or more second grooves 300 for accommodating the interconnection ribbons in the battery array 2 are further provided on the lower main surface of the cover plate 1 and / or the upper main surface of the back plate 4; wherein the second grooves 200 intersect and communicate with the first grooves 100; and the second grooves 300 are part of the hollow cavity 100.

[0038] Specifically, since the battery array 2 is generally a sheet structure, in order to ensure that the battery array 2 does not bend and thus affect the performance of the battery array 2, in the embodiment of the present utility model, if the first groove 200 is as Figure 2 As shown, the second groove 300 is only provided on the lower main surface of the cover plate 1. Figure 3 As shown, the second groove 300 is synchronously arranged on the cover plate 1 and the back plate 4, and the second groove 300 is also synchronously arranged on the cover plate 1 and the back plate 4. For example, the positional relationship between the second groove 300 and the first groove 200 can be as follows: Figure 5 and Figure 6 As shown, Figure 5 is a schematic diagram of the planar structure of the first groove 200 and the second groove 300, Figure 6 The cross-sectional structure diagram of the first groove 200 is shown in FIG. It is understood that in the battery array 2, the interconnection belt realizes the electrical connection between multiple battery strings, so the setting direction of the interconnection belt and the battery string is intersecting, usually vertically arranged. Therefore, the second groove 300 and the first groove 200 in the embodiment of the present invention are also arranged perpendicularly to each other in a preferred embodiment. In addition, for different battery array 2 structures, the setting position of the interconnection belt is also different. The embodiment of the present invention is based on Figure 5 For example, the case where the interconnection ribbon is arranged at the left and right ends of the battery string is described. When the interconnection ribbon is arranged at other positions, the position of the second groove 300 also changes accordingly and only needs to correspond to the interconnection ribbon.

[0039] In order to ensure that the hollow cavity 100 can be used to place the battery array 2, and the depth is neither too large nor too small, in a further optional embodiment, the depth of the first groove 200 is 100 μm~600 μm, for example, 100 μm, 150 μm, 200 μm, 300 μm, 400 μm, 600 μm, etc.; the depth of the second groove 300 is 100 μm~600 μm, for example, 100 μm, 150 μm, 200 μm, 300 μm, 400 μm, 600 μm, etc. It can be understood that when the first groove 200 and the second groove 300 are only provided on the cover plate 1 or the back plate 4, the depth of the first groove 200 and the second groove 300 itself constitutes the depth of the hollow cavity 100. Therefore, in a further optional embodiment, the depth of the first groove 200 or the second groove 300 is 200 μm~600 μm; when the first groove 200 and the second groove 300 are provided on both the cover plate 1 and the back plate 4 at the same time, the two first grooves 200 symmetrically provided on the lower surface of the cover plate 1 and the upper surface of the back plate 4 jointly constitute the depth of the hollow cavity 100, and similarly, the second grooves 300 symmetrically provided on the lower surface of the cover plate 1 and the upper surface of the back plate 4 also jointly constitute the depth of the hollow cavity 100. Therefore, in a further optional embodiment, the depth of the first groove 200 is 100 μm~300 μm, and the depth of the second groove 300 is also 100 μm~300 μm. The two first grooves 200 and the two second grooves 300 arranged opposite to each other together form a hollow cavity 100 with a depth of 200 μm to 600 μm.

[0040] Regarding the filling layer 3 that seals the cell array 2, in one optional embodiment, the filling material in the filling layer 3 is at least one of epoxy resin, polyurethane, liquid silicone, and silicone oil, and the refractive index of the filling layer 3 is 1.5 to 2.5, for example, 1.5, 2.0, 2.5, etc. The cover plate 1 and back plate 4 in the embodiment of the present invention can be made of conventional glass. The refractive index of the selected filling material is close to that of the glass material, and is between that of the cell array 2 and the glass material. Compared to the lower refractive index front and back adhesive films in the prior art, this effectively reduces optical loss and improves the overall efficiency of the photovoltaic module.

[0041] For photovoltaic modules, it is also necessary to provide a through hole for leading out the interconnection ribbon to connect the interconnection ribbon to the junction box, thereby obtaining a complete photovoltaic module. Therefore, in an optional embodiment, the photovoltaic module provided by the embodiment of the present invention further includes: a lead-out hole 41 provided on the upper main surface of the cover plate 1 or the lower main surface of the back plate 4; the position of the lead-out hole 41 corresponds to the second groove 300 and is connected to the hollow cavity 100. For example, Figure 7 and Figure 8As an example, the location of the lead-out hole 41 is specifically described, wherein: Figure 7 This is a structural diagram of setting the lead-out hole 41 at the edge of the cover plate 1 or the back plate 4. Figure 8 This is a schematic diagram of a structure in which lead-out holes 41 are positioned in the middle area of ​​the cover plate 1 or back plate 4. It is understood that since lead-out holes 41 are used to lead the interconnect ribbons within the battery array 2 for subsequent electrical connection to the junction box, their placement in alignment with the second groove 300 minimizes the length of the interconnect ribbons. Furthermore, the number of lead-out holes 41 can be adjusted based on the actual interconnect ribbon configuration.

[0042] In order to ensure the sealing of the filling layer 3 and prevent the filling layer 3 from leaking out of the lead-out hole 41, in a further optional embodiment, the photovoltaic component provided by the embodiment of the present invention also includes: an encapsulation film arranged in the lead-out hole 41; wherein the encapsulation film encapsulates the filling layer 3 in the hollow cavity 100.

[0043] In summary, the photovoltaic module provided by the present invention improves the structure of the cover and backsheet, so that when the cover and backsheet are stacked, the lower main surface of the cover and the upper main surface of the backsheet can directly contact each other, enclosing a hollow cavity for accommodating the battery array. Compared with the stacked structures with exposed sides in the prior art, this effectively improves the sealing of the photovoltaic module sides, avoiding problems such as water vapor erosion and delamination corrosion. At the same time, the filling layer seals the battery array, further protecting it.

[0044] In one embodiment of the present invention, Figure 9 As shown, this embodiment provides a method for preparing a photovoltaic module, which may include the following steps:

[0045] Step S901: Laying the back plate, the battery array, and the cover plate in sequence, so that the battery array is located in the hollow cavity formed between the cover plate and the back plate; the battery array may be a battery array with a filling layer pre-cured on the surface or a battery array without a filling layer pre-cured on the surface;

[0046] Step S902: Welding the contact surfaces between the cover plate and the back plate in the area where the hollow cavity is not provided;

[0047] In the case where a filling layer is not pre-cured on the surface of the battery array, the method further includes: step S903, pouring a filling material into the hollow cavity and curing it to form a filling layer that seals the battery array;

[0048] In the case where the battery array has a filling layer pre-cured on its surface, before step 1, the method further includes: step S900, in which a filling material is applied to the surface of the blank battery array in a vacuum environment, and after curing, a battery array with a filling layer pre-cured on its surface is obtained.

[0049] It is understood that for a battery array with a pre-cured filling layer, only steps S900 to S902 need to be performed, and the post-filling step S903 does not need to be performed. The battery array with the pre-cured filling layer can be directly stacked with the back plate and cover plate, and then welded in one step. For a battery array without a pre-cured filling layer, step S900 does not need to be performed, and steps S901 to S903 can be performed.

[0050] Among them, the back plate and cover plate laid in step S901 can both be made of glass material, and in an optional embodiment, step S902 can use femtosecond laser welding technology or high-energy laser welding technology to weld the contact surface. It should be noted that compared with other welding technologies, femtosecond laser welding technology has a better welding effect on glass materials. Therefore, when the back plate and cover plate are made of glass material, femtosecond welding technology is selected to achieve the welding function. It can be understood that for different welding materials, corresponding welding technologies can be selected in a targeted manner to ensure the welding effect between different welding materials. This is not specifically limited by the present invention. In addition to welding technology, adhesive bonding or other methods can also be used to fix the cover plate and the back plate into one. In addition, compared with the technology of sealing the edge by hot-melt glass in the prior art, the above-mentioned welding process consumes less energy and has higher welding efficiency, and will not cause local stress changes in the glass, resulting in uneven stress in the glass or a decrease in tempering degree.

[0051] It should be noted that step S903 is limited to the case where there is no pre-cured filling layer on the surface of the battery array, that is, after step S902, the back plate, battery array and cover plate are only welded together, but the hollow cavity is not filled. Therefore, step S903 needs to be performed after welding to pour the filling material into the hollow cavity by post-filling to form a filling layer that seals the battery array. In an optional embodiment, when the filling material is at least one of epoxy resin, polyurethane and liquid silicone, step S903 can be as follows: Figure 10 As shown, specifically including:

[0052] Step S1001: Filling a filling material into the hollow cavity using the lead-out hole provided on the cover plate or the back plate;

[0053] Step S1002 , vacuuming or curing the filling material to form a filling layer; wherein vacuuming is achieved by a laminator or a vacuum furnace; curing includes at least one of the following curing methods: light curing, room temperature curing, and high temperature curing.

[0054] If the backplate has multiple lead-out holes, one of these holes can be used as the filling inlet, and conduits can be installed in the remaining holes. During the filling process, the cavity can be completely filled by observing whether filling material flows out of the conduits in the remaining holes. Specifically, a one-way valve can be installed at the filling inlet to ensure unidirectional filling. Once filling is complete, the conduit and one-way valve can be removed.

[0055] In an optional embodiment, the laminator is a double-chamber laminator, wherein the temperature of the first cavity is 65°C~70°C, and the temperature of the second cavity is 110°C~120°C; the vacuuming time is 5 min~20 min, for example, 5 min, 10 min, 15 min, 20 min, etc.; the curing time is 5 min~20 min, for example, 5 min, 10 min, 12 min, 15 min, 18 min, 20 min, etc.

[0056] In summary, the photovoltaic module manufacturing method provided by the present invention improves the structure of the cover and backsheets, so that after the cover and backsheets are stacked, the lower main surface of the cover and the upper main surface of the backsheet can directly contact each other, enclosing a hollow cavity for accommodating the battery array. Compared with the stacked structures with exposed sides in the prior art, this effectively improves the sealing of the photovoltaic module sides, avoiding problems such as water vapor erosion and delamination corrosion. At the same time, the battery array is sealed by the filling layer, further protecting the battery array.

[0057] Example 1

[0058] A method for preparing a photovoltaic module, comprising:

[0059] S1. Lay, from bottom to top, a back glass with a pre-prepared first and second grooves, a battery array, and a cover glass with a pre-prepared first and second grooves. The depth of the first and second grooves is 275 μm, and the thickness of the battery array is 540 μm. The first and second grooves together form a hollow cavity for accommodating the battery array.

[0060] S2. Use femtosecond laser welding technology to laser weld the contact surface between the cover glass and the back glass;

[0061] S3. Pour liquid silicone into one lead-out hole on the back panel glass, and attach silicone tubes to the remaining lead-out holes. Observe whether silicone flows out of the tubes to determine whether the hollow cavity is fully filled with silicone. Remove the tubes when the cavity is completely filled.

[0062] S4. Use a double-chamber laminator for vacuuming and curing, with one chamber temperature at 65°C for 10 minutes and the second chamber temperature at 110°C for 15 minutes;

[0063] S5. Use butyl adhesive to fill the lead-out hole, frame it, install the junction box, cure it, and test it.

[0064] The test results are as follows: The photovoltaic module prepared in Example 1 was subjected to damp heat testing, dynamic mechanical loading, static mechanical loading, and high-temperature cycling testing. After the damp heat testing and high-temperature cycling, the module's appearance remained unchanged, power loss was within 2.5%, and the conventional module edge blackening problem was not observed after testing. After the dynamic and static mechanical loading tests, the module showed no breakage and no new hidden cracks.

[0065] Example 2

[0066] A method for preparing a photovoltaic module, comprising:

[0067] S1. In a vacuum environment, a filling material is applied to the surface of the battery array and cured to form a filling layer;

[0068] S2. Lay, from bottom to top, a back glass with a pre-prepared first groove and a pre-prepared second groove, a battery array with a cured filling layer, and a cover glass with a pre-prepared first groove and a pre-prepared second groove in sequence; wherein the depth of the first groove and the second groove is 275 μm, and the thickness of the battery array is 540 μm; the first groove and the second groove together form a hollow cavity for accommodating the battery array;

[0069] S3. Use femtosecond laser welding technology to laser weld the contact surface between the cover glass and the back glass;

[0070] S4. Use butyl adhesive to fill the lead-out hole, frame it, install the junction box, cure it, and test it.

[0071] The test results are as follows: The photovoltaic module prepared in Example 2 was subjected to damp heat testing, dynamic mechanical loading, static mechanical loading, and high-temperature cycling testing. After the damp heat testing and high-temperature cycling, the module's appearance remained unchanged, power loss was within 1.5%, and the conventional module edge blackening problem was not observed after the tests. After the dynamic and static mechanical loading tests, the module showed no breakage and no new hidden cracks.

[0072] It can be seen from the test results of the above-mentioned Examples 1 and 2 that the photovoltaic modules and the method for preparing photovoltaic modules provided by the embodiments of the present invention, while ensuring the battery performance, simultaneously improve the dynamic mechanical load and the static mechanical load, thereby effectively improving the airborne strength of the photovoltaic modules.

[0073] The above steps are merely intended to help you understand the structure, method, and core concept of the present invention. A person skilled in the art would be able to make improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications would also fall within the scope of protection of the claims of the present invention.

Claims

1. A photovoltaic module, characterized in that: include: Cover plate (1), battery array (2), filling layer (3) and back plate (4); The cover plate (1) and the back plate (4) are stacked, and the lower main surface of the cover plate (1) and the upper main surface of the back plate (4) are fixedly connected to each other and enclose one or more hollow cavities (100); The hollow cavity (100) is used to place the battery array (2); The filling layer (3) is filled in the hollow cavity (100) and is used to seal the battery array (2).

2. The photovoltaic module according to claim 1, characterized in that One or more first grooves (200) for placing battery strings in the battery array (2) are provided on the lower main surface of the cover plate (1) and / or the upper main surface of the back plate (4); The first groove (200) on the cover plate (1) and / or the back plate (4) constitutes the entire or partial structure of the hollow cavity (100).

3. The photovoltaic module according to claim 2, characterized in that One or more second grooves (300) for placing interconnection strips in the battery array (2) are also provided on the lower main surface of the cover plate (1) and / or the upper main surface of the back plate (4); Wherein, the second groove (300) is cross-connected with the first groove (200); The second groove (300) is a part of the hollow cavity (100).

4. The photovoltaic module according to any one of claims 1 to 3, characterized in that: The depth of the hollow cavity (100) is 200 μm to 600 μm.

5. The photovoltaic module according to claim 1, characterized in that The refractive index of the filling layer (3) is 1.5-2.

5.

6. The photovoltaic module according to claim 1 or 5, characterized in that: The filling material in the filling layer (3) is at least one of epoxy resin, polyurethane, liquid silicone and silicone oil.

7. The photovoltaic module according to claim 3, characterized in that: Also includes: A lead-out hole (41) provided on the upper main surface of the cover plate (1) or the lower main surface of the back plate (4); The position of the lead-out hole (41) corresponds to the second groove (300), and is communicated with the hollow cavity (100).

8. The photovoltaic module according to claim 7, characterized in that: Also includes: A packaging film disposed in the lead-out hole (41); The packaging film encapsulates the filling layer (3) in the hollow cavity (100).

9. The photovoltaic module according to claim 8, characterized in that: The packaging film is a butyl film.

10. The photovoltaic module according to claim 1, characterized in that: The lower main surface of the cover plate (1) and the upper main surface of the back plate (4) are welded to enclose one or more hollow cavities (100).

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