Glass cover plate and photovoltaic module

Abstract

The application relates to the technical field of photovoltaic cells, in particular to a glass cover plate and a photovoltaic module. The glass cover plate comprises a glass body, the glass body has oppositely arranged first and second surfaces along the thickness direction of the glass cover plate, the first surface is provided with a plurality of uniformly distributed recesses, and the recesses located at edge positions have intervals between the recesses and the edges of the glass body. The ratio of the depth D1 of the recesses to the thickness D2 of the glass body along the thickness direction of the glass cover plate satisfies 0.005 <= D1 / D2 <= 0.015. According to the application, the recesses are arranged on the first surface, the structural strength of the glass cover plate is enhanced, the stress is dispersed, the impact resistance of the glass cover plate is improved, the risk of cracks or breakage of the glass cover plate caused by impact is reduced, and the service life of the glass cover plate and the photovoltaic module is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of photovoltaic cells, in particular to a glass cover plate and a photovoltaic module. BACKGROUND

[0002] A photovoltaic module is used to convert solar energy into electric energy by absorbing sunlight. The photovoltaic module includes a glass cover plate, an adhesive film, a cell sheet, a back plate and other components. The glass cover plate is located at the uppermost layer of the photovoltaic module. When hail or other objects fall onto the surface of the glass cover plate, the glass cover plate is easily cracked or even broken by the impact, thereby affecting the normal operation of the photovoltaic module. SUMMARY

[0003] Embodiments of the present application provide a glass cover plate and a photovoltaic module, which are aimed at improving the structural strength of the glass cover plate and prolonging the service life of the photovoltaic module.

[0004] Embodiments of the present application provide a glass cover plate for a photovoltaic module, which includes:

[0005] A glass body having a first surface and a second surface oppositely arranged along the thickness direction of the glass cover plate, the first surface is provided with a plurality of uniformly distributed recesses, and the recesses located at the edge position have a spacing between the recesses and the edge of the glass body.

[0006] The ratio of the depth D1 of the recesses to the thickness D2 of the glass body along the thickness direction of the glass cover plate satisfies: 0.005≤D1 / D2≤0.015.

[0007] In a possible design, the spacing D3 between the recesses located at the edge position and the edge of the glass body satisfies: 2mm≤D3≤8.5mm.

[0008] In a possible design, the depth D1 of the recesses satisfies: 10μm≤D1≤30μm.

[0009] In a possible design, the cross section of the recesses gradually decreases in the direction from the first surface to the second surface.

[0010] In a possible design, the cross section of the recesses along the thickness direction of the glass cover plate is one or more of a circle, a triangle, a rectangle, and a polygon.

[0011] In a possible design, the glass cover plate further includes a porous nanosilica film layer, and the porous nanosilica film layer is arranged on the first surface.

[0012] In one possible design, the refractive index of the porous nano-silica film is 1.28-1.30;

[0013] The thickness of the porous nano-silica film is 100nm-130nm.

[0014] In one possible design, the glass cover also includes a dense silica film and a porous nano silica film.

[0015] The dense silica film is disposed on the first surface, and the porous nano silica film is disposed on the dense silica film.

[0016] In one possible design, the refractive index of the porous nano-silica film is 1.18-1.20, and the thickness of the porous nano-silica film is 100nm-120nm.

[0017] The refractive index of the dense silicon dioxide film is 1.38-1.40, and the thickness of the dense silicon dioxide film is 70nm-90nm.

[0018] This application embodiment also provides a photovoltaic module, the photovoltaic module including a first cover plate, a first encapsulating film, a battery pack, a second encapsulating film and a second cover plate stacked together, the first cover plate being the glass cover plate described above, or the first cover plate and the second cover plate being the glass cover plate described above; the first surface of the glass cover plate is the side away from the battery pack;

[0019] The battery pack includes multiple electrically connected battery cells.

[0020] In this embodiment, embossing is performed on the first surface to form multiple inwardly recessed portions. Without increasing the thickness or weight of the glass cover, the structural strength of the glass cover is enhanced, and stress is dispersed (stress is concentrated at the edges of the recesses, reducing stress concentration and lowering the stress concentration level of the glass cover), thereby improving the impact resistance of the glass cover, reducing the risk of cracking or breaking due to impact, and helping to extend the lifespan of the glass cover and photovoltaic modules.

[0021] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0022] Figure 1 This is a cross-sectional structural diagram of the photovoltaic module provided in this application in a specific embodiment;

[0023] Figure 2 This is a cross-sectional schematic diagram of the glass body provided in this application in a specific embodiment;

[0024] Figure 3 A cross-sectional view of a glass body according to an embodiment of the present application is shown in FIG. 1.

[0025] Figure 4 A cross-sectional view of a glass body according to another embodiment of the present application is shown in FIG. 2.

[0026] Figure 5 A cross-sectional view of a glass body according to another embodiment of the present application is shown in FIG. 3.

[0027] Figure 6 A top view of a glass body according to an embodiment of the present application is shown in FIG. 4.

[0028] Figure 7 A cross-sectional view of a glass cover plate according to an embodiment of the present application is shown in FIG. 5.

[0029] Figure 8 A cross-sectional view of a glass body according to another embodiment of the present application is shown in FIG. 6.

[0030] Figure 9 Light transmittance curves of a glass body according to the present application are shown in FIG. 7.

[0031] Reference signs:

[0032] 1 - photovoltaic module

[0033] 11 - glass cover plate

[0034] 111 - glass body

[0035] 111a - first surface

[0036] 111a1 - recess

[0037] 111a2 - edge position

[0038] 111b - second surface

[0039] 111c - rim

[0040] 112 - porous nanosilica film layer

[0041] 113 - dense silica film layer

[0042] 12 - first cover plate

[0043] 13 - first adhesive film

[0044] 14 - battery

[0045] 15 - second adhesive film

[0046] 16 - second cover plate.

[0047] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate embodiments consistent with the present application and, together with the description, further serve to explain the principles of the application. DETAILED DESCRIPTION

[0048] For a better understanding of the technical solutions of the present application, the embodiments of the present application are described in detail below with reference to the drawings.

[0049] It should be clear that the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0050] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0051] It should be understood that the term "and / or" used herein is only to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0052] It should be noted that the "up", "down", "left", "right" and other orientation words described in the embodiments of the present application are described from the angle shown in the drawings, and should not be understood as a limitation on the embodiments of the present application. In addition, it should be understood in the context that when referring to an element connected to another element "on" or "under", it can be directly connected to another element "on" or "under" or indirectly connected to another element "on" or "under" through an intermediate element.

[0053] As Figure 1 A cross-sectional view of a photovoltaic module 1 is shown, which includes a first cover plate 12, a first adhesive film 13, a cell group 14, a second adhesive film 15 and a second cover plate 16 arranged in layers. That is, the photovoltaic module 1 is composed of a laminated package of the first cover plate 12, the first adhesive film 13, the cell group 14, the second adhesive film 15 and the second cover plate 16. Among them, the photovoltaic module 1 can be a single glass module, that is, the first cover plate 12 is a glass cover plate 11 facing the light source, used for transmitting sunlight. Alternatively, the photovoltaic module 1 can be a double glass module, the first cover plate 12 and the second cover plate 16 are both glass cover plates 11 facing the light source, used for transmitting sunlight.

[0054] In the process of laminating the photovoltaic module 1, the first adhesive film 13 and the second adhesive film 15 are used to encapsulate the battery group 14, prevent the external environment from affecting the performance of the battery group 14, and simultaneously bond the first cover plate 12, the second cover plate 16 and the battery group 14 into an integral whole.

[0055] The material of the first adhesive film 13 and the second adhesive film 15 can be the same or different. For example, the material of the first adhesive film 13 and the second adhesive film 15 can be one of Ethylene-Vinyl Acetate Copolymer (EVA), Polyolefin Elastomer (POE), Polyvinyl Butyral (PVB) and the like, and can also be EPE adhesive film (EVA-POE-EVA co-extrusion structure) or EP adhesive film (EVA-EP co-extrusion structure).

[0056] The battery group 14 includes a plurality of electrically connected battery pieces. Specifically, the battery group 14 includes a plurality of battery strings connected in series or in parallel, and each battery string is formed by a plurality of battery pieces connected in series, and adjacent battery pieces are connected by a welding strip.

[0057] The structure of the battery piece is not limited in the embodiment, and the types of the battery piece include, but are not limited to, Passivated Emitter Rear Cell (PERC), Tunnel Oxide Passivated Contact (TOPCon), Heterojunction with Intrinsic Thin-film (HJT), Interdigitated Back Contact (IBC), perovskite cell and the like.

[0058] For the PERC cell, along the thickness direction, the PERC cell includes, in sequence, a front surface metal silver electrode, a front surface silicon nitride passivation layer, a phosphorus layer emitter, a P-type base silicon layer, a local aluminum back field, a metal aluminum back electrode and a back passivation layer (Al2O3 / SiNx). The PERC cell uses a passivation film to passivate the back surface, replaces the full aluminum back field, enhances the internal back reflection of light on the silicon base, reduces the back surface recombination rate, and improves the efficiency of the cell by 0.5%-1%.

[0059] For the TOPCon cell, along its thickness direction, the TOPCon cell includes, in sequence, a metal silver electrode, a front surface silicon nitride passivation layer, a boron-doped emitter, an N-type base silicon layer, a diffusion-doped layer, an ultra-thin silicon oxide, a doped polysilicon, a silicon nitride, and a metal silver electrode. The back surface of the cell is composed of an ultra-thin silicon oxide layer (1 nm-2 nm) and a phosphorus-doped microcrystalline-amorphous mixed Si thin film, which together form a passivation contact structure. This structure can block the recombination of minority carriers, thereby improving the open-circuit voltage and short-circuit current of the cell. The ultra-thin oxide layer allows the majority carriers to tunnel into the polysilicon layer while blocking the recombination of minority carriers. The good passivation effect of the ultra-thin silicon oxide and the heavily doped silicon thin film causes the energy band of the silicon wafer surface to bend, thereby forming a field passivation effect. The probability of electron tunneling increases significantly, the contact resistance decreases, and the open-circuit voltage and short-circuit current of the cell are improved, thereby improving the conversion efficiency of the cell.

[0060] For the HJT cell, along its thickness direction, the HJT cell includes, in sequence, a front surface low-temperature silver electrode, a front surface conductive thin film, an N-type amorphous silicon thin film, an intrinsic amorphous silicon thin film, an N-type base silicon layer, an intrinsic amorphous silicon thin film, a P-type amorphous silicon thin film, a back surface conductive thin film, and a back surface low-temperature silver electrode.

[0061] For the IBC cell, along its thickness direction, the IBC cell includes, in sequence, a silicon nitride back layer, an N+ front surface field, an N-type base silicon layer, a P+ emitter, an N+ back field, an aluminum oxide passivation layer, a silicon nitride anti-reflection layer, and a metal silver electrode. The IBC cell uses ion implantation technology to obtain a P region and an N region with good uniformity and accurately controllable junction depth. The cell has no grid line on the front surface, which can eliminate the shading current loss of the metal electrode, maximize the utilization of incident photons, and increase the short-circuit current by about 7% compared with conventional solar cells. Due to the back contact structure, the grid line proportion can be appropriately widened, thereby reducing the series resistance and having a high fill factor. The surface passivation and surface light trapping structure can be optimally designed to obtain a lower front surface recombination rate and surface reflection.

[0062] For the perovskite cell, along its thickness direction, the perovskite cell includes, in sequence, a substrate material, a conductive thin film, an electron transport layer (titanium dioxide), a perovskite absorption layer (hole transport layer), and a metal cathode. Perovskite material has a high light absorption coefficient and a long carrier diffusion distance. After the absorbed photons are converted into electrons, they are easily collected by the electrode with little loss, thus generating a high photovoltage and current, making perovskite exhibit high photoelectric conversion efficiency.

[0063] The battery piece can adopt a multi-main grid scheme, which can shorten the current conduction path, reduce internal loss, thereby improving the power of the photovoltaic module 1, and also can reduce the cost of the photovoltaic module 1; or a main grid-free scheme can be adopted, the welding strip is replaced by the original main grid, and is directly connected with the fine grid, so that the silver paste consumption can be greatly reduced, thereby reducing the cost of the photovoltaic module 1.

[0064] The structure of the glass cover plate (the first cover plate / the first cover plate and the second cover plate) will be described in detail below with reference to the drawings.

[0065] As Figure 2 shown is a cross-sectional view of the glass body 111 in an embodiment, the glass cover plate 11 includes the glass body 111, along the thickness direction Z of the glass cover plate 11, the glass body 111 has oppositely arranged first and second surfaces 111a and 111b, the first surface 111a is the light-receiving surface of the glass body 111 away from the battery group 14, and is located at the outermost side of the photovoltaic module 1. Therefore, the first surface 111a is easy to be impacted, resulting in cracks or even breakage of the glass cover plate 11.

[0066] Therefore, the first surface 111a of the glass cover plate 11 is stamped in this embodiment, so that the first surface 111a of the glass cover plate 11 forms a plurality of reinforcing structures. Specifically, embossing is performed on the first surface 111a, so that the first surface 111a forms a plurality of inwardly recessed recessed portions 111a1.

[0067] In this embodiment, the recessed portion 111a1 is stamped on the first surface 111a of the glass body 111, and part of the structure of the first surface 111a is recessed in the direction of the second surface 111b to form. Rather than setting a protruding structure on the first surface 111a and stamping a recessed portion 111a1 on the protruding structure, or setting a protruding portion on the first surface 111a and forming a recessed portion 111a1 between adjacent protruding portions.

[0068] It should be noted that the recessed portion 111a1 in this embodiment is stamped on the first surface 111a of the glass body 111, and part of the structure of the first surface 111a is recessed in the direction of the second surface 111b to form. Rather than setting a protruding structure on the first surface 111a and stamping a recessed portion 111a1 on the protruding structure, or setting a protruding portion on the first surface 111a and forming a recessed portion 111a1 between adjacent protruding portions.

[0069] Please continue to refer to Figure 2 , along the thickness direction Z of the glass cover plate 11, the ratio of the depth D1 of the recessed portion 111a1 to the thickness D2 of the glass body 111 satisfies: 0.005≤D1 / D2≤0.015.

[0070] Exemplarily, the ratio of the depth D1 of the recessed portion 111a1 to the thickness D2 of the glass body 111 can be 0.005, 0.006, 0.007, 0.008, 0.009, 0.010, 0.011, 0.012, 0.013, 0.014, 0.015, etc.

[0071] In this embodiment, the ratio of the depth D1 of the recessed portion 111a1 to the thickness D2 of the glass body 111 should not be too large or too small. If D1 / D2 is too large (e.g., greater than 0.015), the depth of the recessed portion 111a1 is too large, resulting in a thinner structure of the glass body 111 below the recessed portion 111a1, which reduces the strength of the structure and can cause the structure to break under pressure during the lamination process. If D1 / D2 is too small (e.g., less than 0.005), the depth of the recessed portion 111a1 is too small, resulting in an insignificant improvement in the impact resistance of the first surface 111a of the glass body 111 after the recessed portion 111a1 is provided.

[0072] Therefore, when the ratio of the depth D1 of the recessed portion 111a1 to the thickness D2 of the glass body 111 satisfies 0.005≤D1 / D2≤0.015, the impact resistance of the first surface 111a of the glass body 111 can be enhanced, and the structural strength of the glass body 111 below the recessed portion 111a1 can also be ensured.

[0073] In this embodiment, the depth D1 of the recessed portion 111a1 should not be too large or too small. If D1 is too large (e.g., greater than 30 μm), the structure of the glass body 111 below the recessed portion 111a1 is relatively thin, which reduces the strength of the structure and can cause the structure to break under pressure during the lamination process. If D1 is too small (e.g., less than 10 μm), the impact resistance of the first surface 111a of the glass body 111 after the recessed portion 111a1 is provided is not significantly improved.

[0074] Exemplarily, the depth D1 of the recessed portion 111a1 can be 10 μm, 12 μm, 14 μm, 16 μm, 18 μm, 20 μm, 22 μm, 24 μm, 26 μm, 28 μm, 30 μm, etc.

[0075] In this embodiment, the depth D1 of the recessed portion 111a1 should not be too large or too small. If D1 is too large (e.g., greater than 30 μm), the structure of the glass body 111 below the recessed portion 111a1 is relatively thin, which reduces the strength of the structure and can cause the structure to break under pressure during the lamination process. If D1 is too small (e.g., less than 10 μm), the impact resistance of the first surface 111a of the glass body 111 after the recessed portion 111a1 is provided is not significantly improved.

[0076] Therefore, when the depth D1 of the recessed portion 111a1 satisfies 10 μm≤D1≤30 μm, the impact resistance of the first surface 111a of the glass body 111 can be enhanced, and the structural strength of the glass body 111 below the recessed portion 111a1 can also be ensured.

[0077] Further, please continue to refer to Figure 2 The recess 111a1 at the edge position 111a2 has a spacing D3 between the edge 111c of the glass body 111. Wherein, the edge 111c refers to the edge position of the outer periphery of the first surface 111a, the edge position 111a2 refers to the edge position 111a2 of the area where the plurality of recesses 111a1 on the first surface 111a are located (represented by the dashed box area in the figure), and the recess 111a1 at the edge position 111a2 refers to the recess 111a1 at the outermost periphery of the plurality of recesses 111a1. The edge 111c of the glass body 111 of the embodiment is not provided with the recess 111a1, avoiding the edge 111c of the glass body 111 being notched, so that the edge 111c of the glass body 111 is the original thickness of the glass body 111, so as to ensure the connection strength of the edge position 111a2 of the photovoltaic module 1 and the frame.

[0078] Specifically, the spacing D3 between the recess 111a1 at the edge position 111a2 and the edge 111c of the glass body 111 satisfies: 2mm≤D3≤8.5mm.

[0079] Exemplarily, the spacing D3 between the recess 111a1 at the edge position 111a2 and the edge 111c of the glass body 111 can be 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, etc.

[0080] In this embodiment, the spacing D3 between the recess 111a1 at the edge position 111a2 and the edge 111c of the glass body 111 should not be too large. If D3 is too large (such as greater than 8.5mm), the distance between the recess 111a1 at the edge position 111a2 on the first surface 111a and the edge 111c of the first surface 111a is large, resulting in that the area on the first surface 111a without the recess 111a1 is large, which affects the structural strength of the area on the first surface 111a close to the edge 111c.

[0081] At the same time, the embodiment limits 2mm≤D3, which leaves an error value for the processing of the recess 111a1 at the edge position 111a2, avoiding the edge 111c of the glass body 111 being notched due to processing error.

[0082] Alternatively, please refer to Figure 3 , Figure 3As a cross-sectional schematic view of the glass body 111 in another embodiment, in some embodiments, the recesses 111a1 can be arranged on the entire first surface 111a of the glass body 111. That is, the interval D3 between the recess 111a1 at the edge position 111a2 and the edge 111c of the glass body 111 satisfies: 0mm≤D3≤8.5mm. However, in this embodiment, when the interval D3 between the recess 111a1 at the edge position 111a2 and the edge 111c of the glass body 111 is equal to 0mm, the thickness of the edge 111c of the glass body 111 is still the original thickness D2 of the glass body 111.

[0083] Please continue to refer to Figure 2 , in the direction from the first surface 111a to the second surface 111b, the cross section of the recess 111a1 gradually decreases, facilitating the processing and forming of the recess 111a1.

[0084] In some embodiments, the first surface 111a can have intervals between adjacent recesses 111a1, as shown in Figure 2 . Alternatively, the first surface 111a can have adjacent recesses 111a1 arranged in close proximity, as shown in Figure 4 , Figure 4 As a cross-sectional schematic view of the glass body 111 in another embodiment. The arrangement of the recesses 111a1 on the first surface 111a can be set according to actual conditions, which is not specifically limited in this embodiment.

[0085] In some embodiments, the cross section of the recess 111a1 along the thickness direction Y perpendicular to the glass cover plate 11 can be triangular, arc-shaped, trapezoidal, etc. Specifically, please refer to Figure 1 and Figure 5 , Figure 1 , the cross section of the recess 111a1 along the thickness direction Y perpendicular to the glass cover plate 11 is triangular, Figure 5 , the cross section of the recess 111a1 along the thickness direction Y perpendicular to the glass cover plate 11 is arc-shaped. Alternatively, the cross section of the recess 111a1 along the thickness direction Y perpendicular to the glass cover plate 11 can also be other shapes, which are not limited in this embodiment.

[0086] In some embodiments, the cross section of the recess 111a1 along the thickness direction Z of the glass cover plate 11 can be one or more of circular, triangular, rectangular, and polygonal. For details, please refer to Figure 6The cross section of the recess 111a1 along the thickness direction Z of the glass cover plate 11 is circular or square, and there is a gap between adjacent recesses 111a1. Among them, when the cross section of the recess 111a1 along the thickness direction Z of the glass cover plate 11 is circular, the recess 111a1 can be a conical, semicircular or other structure. When the cross section of the recess 111a1 along the glass cover plate 11 is triangular, the recess 111a1 can be a triangular pyramid structure. When the cross section of the recess 111a1 along the glass cover plate 11 is quadrilateral, the recess 111a1 can be a quadrangular pyramid structure. Alternatively, the recess 111a1 can also be other shapes, which are not limited in the present embodiment.

[0087] As shown in FIG. 1, the glass cover plate 11 is provided with a plurality of recesses 111a1, and the plurality of recesses 111a1 are arranged in a staggered manner. Figure 7 FIG. 2 shows a cross-sectional schematic view of the glass cover plate 11 in an embodiment. The glass cover plate 11 includes a glass body 111 and a porous nanosilica film layer 112. The glass body 111 has a first surface 111a, and the porous nanosilica film layer 112 is arranged on the first surface 111a.

[0088] The main component of the porous nanosilica film layer 112 is porous nanosilica. Based on the film optical principle, the film layer thickness is set at one quarter of the sensitive wavelength of the solar cell sheet by using nanotechnology, so as to realize the interference cancellation of the reflected light of the solar light wave on the film layer surface and the glass surface, increase the transmittance, and reduce the reflection. Therefore, the porous nanosilica film layer 112 has the functions of increasing the transmittance and reducing the reflection. The porous nanosilica film layer 112 is covered on the first surface 111a, so as to reduce the light reflection of the glass cover plate 11, improve the light transmittance of the glass cover plate 11, reduce the light loss, effectively improve the light energy utilization rate and service life of the photovoltaic module 1, and efficiently utilize the solar energy.

[0089] In addition, the porous nanosilica film layer 112 has excellent light transmittance, reflection reduction performance, high thermal resistance, certain anti-fading property and hydrophobicity, and has a self-cleaning function, so as to avoid the reduction of the power generation efficiency of the photovoltaic module 1 caused by the dirt on the surface of the glass cover plate 11.

[0090] The refractive index of the porous nanosilica film layer 112 is 1.28-1.30, and the thickness of the porous nanosilica film layer 112 is 100nm-130nm.

[0091] For example, the refractive index of the porous nanosilica film layer 112 is 1.28, 1.29 or 1.3, and the thickness of the porous nanosilica film layer 112 is 100nm, 120nm or 130nm. Preferably, the refractive index of the porous nanosilica film layer 112 is 1.3, and the thickness of the porous nanosilica film layer 112 is 110nm.

[0092] In this embodiment, the refractive index of the porous nanometer silica film layer 112 is 1.28-1.30, and the thickness of the porous nanometer silica film layer 112 is 100-130 nm, which can improve the light transmittance of the glass cover plate 11, reduce light loss, and improve the power of the photovoltaic module 1.

[0093] It should be noted that the first surface 111a of the glass body 111 is provided with a recess 111a1, and the first surface 111a is uneven. After the porous nanometer silica film layer 112 is plated on the first surface 111a, the porous nanometer silica film layer 112 is also uneven.

[0094] As shown in FIG. 1, the glass cover plate 11 includes a glass body 111, a dense silica film layer 113, and a porous nanometer silica film layer 112. The glass body 111 has a first surface 111a, the dense silica film layer 113 is arranged on the first surface 111a, and the porous nanometer silica film layer 112 is arranged on the dense silica film layer 113. Figure 8 As shown in FIG. 2, the glass cover plate 11 includes a glass body 111, a dense silica film layer 113, and a porous nanometer silica film layer 112. The glass body 111 has a first surface 111a, the dense silica film layer 113 is arranged on the first surface 111a, and the porous nanometer silica film layer 112 is arranged on the dense silica film layer 113.

[0095] In order to further illustrate that the light transmittance of the glass cover plate 11 is improved when the glass body 111 is provided with a single-layer film (the porous nanometer silica film layer 112) and a double-layer film (the dense silica film layer 113 and the porous nanometer silica film layer 112), the light transmittance of the glass body 111 without a film, with a single-layer film (the porous nanometer silica film layer 112), and with a double-layer film (the dense silica film layer 113 and the porous nanometer silica film layer 112) is recorded and compared.

[0096] It should be noted that the other parameters of the glass body 111 without a film, with a single-layer film, and with a double-layer film are the same, and will not be described here.

[0097] For details, please refer to Figure 9 As shown in FIG. 3, the light transmittance curves of the glass body 111 without a film, with a single-layer film, and with a double-layer film are shown. As shown in FIG. 4, the light transmittance curves of the glass body 111 without a film, with a single-layer film, and with a double-layer film are shown. Figure 9 As shown in FIG. 3, the light transmittance curves of the glass body 111 without a film, with a single-layer film, and with a double-layer film are shown. As shown in FIG. 4, the light transmittance curves of the glass body 111 without a film, with a single-layer film, and with a double-layer film are shown. Figure 9

[0098] ​The average light transmittance of the glass body 111 is 91.61, the average light transmittance of the glass body 111 coated with a single layer of film is 93.94, and the average light transmittance of the glass body 111 coated with double layers of film is 94.29.

[0099] Therefore, compared with the glass body 111 without film coating, the glass body 111 coated with a single layer of film shows higher light transmittance. Compared with the glass body 111 coated with a single layer of film, the glass body 111 coated with double layers of film shows higher light transmittance.

[0100] Therefore, when the double layers of film are coated on the glass body 111, the light transmittance of the glass cover plate 11 can be further improved. That is, the synergistic effect of the dense silicon dioxide film layer 113 and the porous nanometer silicon dioxide film layer 112 can improve the light energy utilization rate and improve the photoelectric conversion efficiency. At the same time, the two layers of film provided on the glass body 111 are beneficial to improve the dirt resistance of the glass cover plate 11, thereby reducing the possibility that the surface dirt of the glass cover plate 11 affects the power generation efficiency of the photovoltaic module 1.

[0101] The refractive index of the porous nanometer silicon dioxide film layer 112 is 1.18-1.20, and the thickness of the porous nanometer silicon dioxide film layer 112 is 100nm-120nm. The refractive index of the dense silicon dioxide film layer 113 is 1.38-1.40, and the thickness of the dense silicon dioxide film layer is 70nm-90nm.

[0102] For example, the refractive index of the porous nanometer silicon dioxide film layer 112 can be 1.18, 1.19, 1.20, etc., and the thickness of the porous nanometer silicon dioxide film layer 112 can be 100nm, 110nm, 120nm, etc. The refractive index of the dense silicon dioxide film layer 113 is 1.38, 1.39, 1.40, etc., and the thickness of the dense silicon dioxide film layer is 70nm, 80nm, 90nm, etc.

[0103] In this embodiment, when the refractive index of the porous nanometer silicon dioxide film layer 112 is 1.18-1.20, the thickness of the porous nanometer silicon dioxide film layer 112 is 100nm-120nm, the refractive index of the dense silicon dioxide film layer 113 is 1.38-1.40, and the thickness of the dense silicon dioxide film layer is 70nm-90nm, the light transmittance of the glass cover plate 11 can be further improved, the light loss can be reduced, and the power of the photovoltaic module 1 can be improved.

[0104] It should be noted that the first surface 111a of the glass body 111 is provided with a recessed portion 111a1, so that the first surface 111a is uneven. After the dense silicon dioxide film layer 113 is coated on the first surface 111a, and the porous nanometer silicon dioxide film layer 112 is coated on the dense silicon dioxide film layer 113, the dense silicon dioxide film layer 113 and the porous nanometer silicon dioxide film layer 112 are also uneven.

[0105] The above descriptions are only the preferred embodiments of the present application, and are not intended to limit the present application. The present application can have various changes and modifications for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A glass superstate for a photovoltaic module (1), characterized in that, The glass cover plate (11) comprises: a glass body (111) having a first surface (111a) and a second surface (111b) oppositely arranged along a thickness direction (Z) of the glass cover plate (11), the first surface (111a) being provided with a plurality of uniformly distributed recesses (111a1) capable of enhancing the structural strength of the glass body (111), and the recesses (111a1) located at an edge position (111a2) having a spacing between the glass body (111) and the edge (111c); a ratio of a depth D1 of the recesses (111a1) to a thickness D2 of the glass body (111) along the thickness direction (Z) of the glass cover plate (11) satisfies: 0.005≤D1 / D2≤0.008; the depth D1 of the recesses (111a1) satisfies: 10μm≤D1≤20μm; the spacing D3 between the recesses (111a1) located at the edge position (111a2) and the edge (111c) of the glass body (111) satisfies: 2mm≤D3≤3.5mm.

2. The glass cover sheet of claim 1, wherein, a cross section of the recesses (111a1) gradually decreases in a direction from the first surface (111a) to the second surface (111b).

3. The glass cover sheet of claim 1, wherein, a cross section of the recesses (111a1) along the thickness direction (Z) of the glass cover plate (11) is one or more of a circle, a triangle, a rectangle, and a polygon.

4. The glass cover sheet of claim 1, wherein, The glass cover plate (11) further comprises a porous nanosilica film layer (112) arranged on the first surface (111a).

5. The glass cover sheet of claim 4, wherein, The porous nanosilica film layer (112) has a refractive index of 1.28-1.30; The porous nanosilica film layer (112) has a thickness of 100nm-130nm.

6. The glass cover sheet of claim 1, wherein, The glass cover plate (11) further comprises a dense silica film layer (113) and a porous nanosilica film layer (112); The dense silica film layer (113) is arranged on the first surface (111a), and the porous nanosilica film layer (112) is arranged on the dense silica film layer (113).

7. The glass cover sheet of claim 6, wherein, The porous nanosilica film layer (112) has a refractive index of 1.18-1.20 and a thickness of 100nm-120nm; The dense silica film layer (113) has a refractive index of 1.38-1.40 and a thickness of 70nm-90nm.

8. A photovoltaic module, characterized by, The photovoltaic module (1) comprises a first cover plate (12), a first adhesive film (13), a battery group (14), a second adhesive film (15) and a second cover plate (16) which are stacked, the first cover plate (12) is the glass cover plate (11) of any one of claims 1 to 7, or the first cover plate (12) and the second cover plate (16) are the glass cover plate (11) of any one of claims 1 to 7; the first surface (111a) of the glass cover plate (11) is the surface away from the battery group (14); The battery group (14) comprises a plurality of electrically connected battery pieces.

Images