Bifacial photovoltaic modules

Abstract

The utility model provides a double-sided photovoltaic power generation module, which includes a glass cover plate, a first packaging film, a battery layer, a second packaging film and a back plate from top to bottom, wherein: a plurality of concave-convex structures are arranged on the side of the back plate facing the battery layer; a reflective film is also arranged on the side of the back plate facing the battery layer, and the position of the reflective film matches the position of the gap between each battery cell in the battery layer. The back plate of the double-sided photovoltaic power generation module is provided with a plurality of concave-convex structures; a reflective film is arranged on the back plate with a plurality of concave-convex structures, and the reflective film matches and corresponds to the gap between the battery cells, so that the incident light can be efficiently reflected to the battery cell through the reflective film without blocking the back battery cell, thereby greatly improving the module power.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic components, in particular to a double-sided power generation photovoltaic component. Background Art

[0002] With the booming photovoltaic industry, a wide variety of photovoltaic modules have emerged, and each company has launched its own unique product designs based on its own characteristics. At the same time, due to differences in layout design, upstream materials such as transparent grid backplanes and glazed glass must be customized according to different customers and different formats. As a result, the screen production line needs to be frequently switched, which invisibly leads to some waste of resources.

[0003] Furthermore, the photovoltaic industry is currently pursuing extremely high-efficiency modules, and has introduced interstitial reflective films. These films, through directional reflection, enhance the utilization of light in non-light-absorbing areas, thereby increasing module power. However, due to the limitations of the surface metal layer, interstitial reflective films pose the risk of short circuits during the module manufacturing process. Utility Model Content

[0004] The utility model provides a bifacial photovoltaic module for effectively improving module power and bifaciality. The bifacial photovoltaic module comprises, from top to bottom, a glass cover, a first encapsulation film, a cell layer, a second encapsulation film, and a backsheet, wherein:

[0005] The back plate is provided with a plurality of concave and convex structures on the side facing the battery layer;

[0006] A reflective film is provided on the side of the back plate facing the cell layer. The position of the reflective film matches the position of the gap between the cells in the cell layer. The reflective film is formed with a reflective surface corresponding to the concave-convex structure.

[0007] In a specific implementation, the side of the back plate facing the battery cell layer has a plurality of sawtooth-shaped protrusions, or the side of the back plate facing the battery cell layer has a plurality of triangular pyramid-shaped protrusions.

[0008] In a specific implementation, the reflective film is a reflective film made of aluminum metal.

[0009] In a specific implementation, the thickness of the aluminum metal reflective film is 1 μm to 10 μm.

[0010] In a specific implementation, the reflective film is adhered to the back plate by using UV-resistant adhesive.

[0011] In a specific implementation, both sides of the back plate are provided with a fluorine coating.

[0012] In a specific implementation, the fluorine coating is a FEVE fluorine resin coating.

[0013] In a specific implementation, the thickness of the fluorine coating is 10 μm to 35 μm.

[0014] In a specific implementation, the first packaging film and the second packaging film are PVF films or PVDF films.

[0015] In a specific implementation, the backboard is a transparent backboard made of PET material.

[0016] The bifacial photovoltaic module provided by this utility model comprises, from top to bottom, a glass cover, a first encapsulating film, a cell layer, a second encapsulating film, and a backsheet. The backsheet is provided with a plurality of concave-convex structures on the side facing the cell layer; a reflective film is also provided on the side facing the cell layer, the position of the reflective film matching the position of the gaps between the cells in the cell layer. The backsheet of this bifacial photovoltaic module is provided with a plurality of concave-convex structures; a reflective film is provided on this backsheet with the plurality of concave-convex structures, and the reflective film is provided on the backsheet with the plurality of concave-convex structures, and the reflective film matches and corresponds to the gaps between the cells. This allows the reflective film to efficiently reflect incident light to the cells without blocking the back cells, significantly increasing the module's power output. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the specific embodiments or the description of the prior art. Obviously, the drawings described below are only some specific embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0018] Figure 1 This is a schematic structural diagram of a triangular pyramid faceted back plate according to a specific embodiment of the present invention;

[0019] Figure 2 This is a schematic structural diagram of a sawtooth faceted back plate according to a specific embodiment of the present invention;

[0020] Figure 3 This is a schematic top view of the back plate and the reflective film according to a specific embodiment of the present invention;

[0021] Figure 4 This is a schematic cross-sectional view of a back plate according to a specific embodiment of the present invention;

[0022] Figure 5 It is a schematic diagram of the packaging structure of a double-sided photovoltaic module according to a specific embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the specific embodiment of the present invention more clear, the specific embodiment of the present invention is further described in detail with reference to the accompanying drawings. Here, the schematic specific embodiment of the present invention and its description are used to explain the present invention, but are not intended to limit the present invention.

[0024] like Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 5 As shown, in order to effectively improve the module power and bifaciality, the bifacial photovoltaic module includes, from top to bottom, a glass cover 51, a first encapsulation film, a cell layer, a second encapsulation film and a back sheet 41, wherein:

[0025] The back plate 41 is provided with a plurality of concave and convex structures on the side facing the battery layer;

[0026] A reflective film 42 is provided on the side of the back plate 41 facing the cell layer. The position of the reflective film 42 matches the gap position between the cells 52 in the cell layer. The reflective film 42 forms a reflective surface corresponding to the concave-convex structure.

[0027] In specific implementation, Figure 4 As shown, the reflective film 42 is fitted with the concave-convex structure and is also arranged in a concave-convex structure and is arranged at the gap between the battery cells 52, thereby effectively avoiding blocking the back battery cells 52.

[0028] In specific implementation, there are many implementation options for the arrangement of the plurality of concave-convex structures on the back surface. Figure 2 As shown, the back plate 41 may have a plurality of sawtooth protrusions 21 on the side facing the battery layer, or, as shown in FIG. Figure 1 As shown, the back plate 41 may further have a plurality of triangular pyramidal protrusions 11 on the side facing the cell layer. Specifically, the included angle of the sawtooth protrusions 21 may be less than or equal to 90°, thereby more effectively utilizing incident light at different angles.

[0029] Furthermore, when providing the concave-convex structure, the backsheet 41 can be calendered to achieve this structure, thereby improving light utilization. Specifically, in actual applications, the concave-convex structures of the backsheet 41 can be provided in a variety of shapes, not just sawtooth or triangular pyramidal. Calendering roller patterns can also be designed as needed, so that the surface of the backsheet 41 forms a variety of concave-convex structures after being rolled. Specifically, the thickness of the backsheet 41 can be selected based on the actual system voltage required by the power station.

[0030] In practice, the reflective film 42 can be made of a variety of materials. For example, aluminum has excellent reflective properties and a relatively stable structure, so the reflective film 42 can be made of aluminum. Furthermore, the thickness of the aluminum reflective film can be 1 μm to 10 μm, with 5 μm being optimal, to effectively ensure the overall flatness of the backplate 41.

[0031] In specific implementation, there are many implementation schemes for fixing the reflective film 42, for example, Figure 4 As shown, since the UV-resistant adhesive 43 has excellent durability and will not come unglued due to light exposure, the connection stability of the reflective film 42 can be effectively guaranteed, and the reflective film 42 can be adhered to the backboard 41 through the UV-resistant adhesive 43.

[0032] In a specific implementation, in order to effectively reduce the risk of tin beads piercing the adhesive film and contacting the metal layer to cause a short circuit, and to reduce the damage of ultraviolet rays to the back plate 41 after the reflective film 42 is attached, an insulating layer can be provided on the surface of the reflective film 42. Figure 4 As shown, both sides of the back plate 41 may be provided with a fluorine coating 44 or a transparent fluorine film as an insulating layer. The fluorine coating 44 or the transparent fluorine film can also effectively protect the back plate 41 from UV damage, preventing the back plate 41 from yellowing and brittle fracture, thereby improving the durability of the back plate 41.

[0033] In practice, the fluorine coating 44 can be selected in a variety of ways. For example, the fluorine coating 44 can be a FEVE fluororesin coating. Furthermore, based on the aforementioned insulation structure, it can be seen that the reflective film 42 in conventional double-glass film assembly products also poses a short-circuit risk. Therefore, FEVE film can also be applied to the surface of existing double-glass reflective film to provide insulation and improve product performance.

[0034] Furthermore, the thickness of the fluorine coating 44 can be set in various embodiments. For example, the thickness of the fluorine coating 44 can be 10 μm to 35 μm, with 15 μm being the most preferred. The 15 μm thick fluorine coating 44 can cover the reflective film 42 from below while ensuring light transmittance.

[0035] In a specific implementation, there are multiple implementation options for selecting the materials of the first encapsulation film and the second encapsulation film. For example, both the first encapsulation film and the second encapsulation film can be PVF films or PVDF films.

[0036] In a specific implementation, there are multiple implementation options for the material of the back plate 41 . For example, the back plate 41 may be a transparent back plate 41 made of PET.

[0037] In a specific implementation, the bifacial photovoltaic module can be a transparent single-glass module. By performing a rolling design on the back plate 41, the power generation performance of the single-glass module can be effectively improved.

[0038] Specifically, this application focuses on the need to change screens for different customers during the backplane / glass printing process, as well as the risk of short circuits in components after lamination. By optimizing the transparent grid backplane manufacturing process, the following multiple effects can be achieved:

[0039] a. It is beneficial to improve the power and bifaciality of components;

[0040] b. It can be customized according to different customers without changing the screen;

[0041] c. Reduce delivery cycle and cost, and reduce component manufacturing process steps;

[0042] d. Reduce the risk of micro short circuits, reduce the hidden crack rate of components, and improve output yield.

[0043] In summary, the bifacial photovoltaic module provided by the present invention comprises, from top to bottom, a glass cover plate 51, a first encapsulating film, a cell layer, a second encapsulating film, and a backsheet 41. The backsheet 41 facing the cell layer is provided with a plurality of concave-convex structures. The backsheet 41 facing the cell layer is also provided with a reflective film 42, the position of which matches the position of the gaps between the cells 52 in the cell layer. The backsheet 41 of this bifacial photovoltaic module is provided with a plurality of concave-convex structures. By providing a reflective film on this backsheet 41 with the plurality of concave-convex structures, and by matching and corresponding the gaps between the cells 52, the reflective film can efficiently reflect incident light to the cells 52 without blocking the back cells 52, significantly increasing the module's power.

[0044] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the utility model in detail. It should be understood that the above description is only a specific implementation method of the utility model and is not intended to limit the scope of protection of the utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the utility model should be included in the scope of protection of the utility model.

Claims

1. A double-sided photovoltaic module, characterized in that: The bifacial photovoltaic module comprises, from top to bottom, a glass cover plate, a first encapsulation film, a cell layer, a second encapsulation film and a back plate, wherein: The back plate is provided with a plurality of concave-convex structures on the side facing the battery layer; A reflective film is arranged on the side of the back plate facing the battery layer, the position of the reflective film matches the position of the gap between the battery cells in the battery layer, and the reflective film forms a reflective surface corresponding to the concave-convex structure.

2. The double-sided photovoltaic module according to claim 1, characterized in that: The side of the back plate facing the battery sheet layer has a plurality of sawtooth-shaped protrusions, or the side of the back plate facing the battery sheet layer has a plurality of triangular pyramid-shaped protrusions.

3. The double-sided photovoltaic module according to claim 1, characterized in that: The reflective film is made of aluminum metal.

4. The double-sided photovoltaic module according to claim 3, characterized in that: The thickness of the aluminum metal reflective film is 1 μm to 10 μm.

5. The double-sided photovoltaic module according to claim 1, characterized in that: The reflective film is adhered to the back plate by UV-resistant adhesive.

6. The double-sided photovoltaic assembly according to claim 1, characterized in that: Both sides of the back plate are provided with fluorine coatings.

7. The double-sided photovoltaic assembly according to claim 6, characterized in that: The fluorine coating is a FEVE fluorine resin coating.

8. The double-sided photovoltaic assembly according to claim 6, characterized in that: The fluorine coating has a thickness of 10 μm to 35 μm.

9. The double-sided photovoltaic assembly according to claim 1, characterized in that: The first packaging film and the second packaging film are PVF films or PVDF films.

10. The double-sided photovoltaic assembly according to claim 1, characterized in that: The back plate is a transparent back plate made of PET material.

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