CN112054084A

CN112054084A - Solar module

Info

Publication number: CN112054084A
Application number: CN202010850028.XA
Authority: CN
Inventors: 郭证翔
Original assignee: AU Optronics Corp
Current assignee: AU Optronics Corp
Priority date: 2020-08-21
Filing date: 2020-08-21
Publication date: 2020-12-08
Also published as: TW202209695A; TWI775221B; WO2022036730A1

Abstract

A solar module comprises a back plate, a plurality of light reflecting parts, a connecting layer, packaging materials, a plurality of photovoltaic elements and a transparent plate. The average reflectivity of the backplane is greater than 0 over a wavelength range of 500 nanometers to 1200 nanometers. The reflective portions are disposed on the back plate, and the average reflectivity of each reflective portion in the wavelength range of 300 nm to 1200 nm is greater than or equal to 50%. The connecting layer is arranged on the back plate and covers the light reflecting parts. The packaging material is arranged on the connecting layer. The photovoltaic elements are arranged in the packaging material and respectively cover the light reflecting parts. The transparent plate is arranged on the packaging material.

Description

Solar module

Technical Field

The present invention relates to a solar module, and more particularly, to a solar module including a plurality of light reflecting portions.

Background

The solar modules in existence generally comprise a back plate, and the main color of the solar modules in appearance is mostly the color of the back plate. Therefore, the apparent color of the solar module is usually determined by the back sheet. However, the generated power of some solar modules is greatly affected by the color of the back sheet, so that the generated power of some solar modules may be greatly reduced due to some color of the back sheet.

Disclosure of Invention

At least one embodiment of the present invention provides a solar module, which includes a plurality of light-reflecting portions to improve power generation.

At least one embodiment of the invention provides a solar module, which includes a back plate, the light reflecting portion, a connecting layer, a packaging material, a plurality of photovoltaic elements, and a transparent plate. The average reflectivity of the backplane is greater than 0 over a wavelength range of 500 nanometers to 1200 nanometers. The light reflecting parts are arranged on the back plate, wherein the light reflecting parts are separated from each other, and the average reflectivity of each light reflecting part in the wavelength range of 300 nanometers to 1200 nanometers is greater than or equal to 50%. The connecting layer is arranged on the back plate and covers the light reflecting parts. The packaging material is arranged on the connecting layer. The photovoltaic elements are arranged in the packaging material, wherein the photovoltaic elements respectively cover the light reflecting parts. The transparent plate is arranged on the packaging material.

In at least one embodiment of the present invention, the back plate includes a reflective plate and a colored layer. The colored layer is formed on the reflector plate, wherein the light reflecting parts are arranged on the colored layer.

In at least one embodiment of the present invention, the average reflectivity of the back plate in the wavelength range of 500 nm to 1200 nm is greater than 20%.

In at least one embodiment of the present invention, the color of the colored layer is black.

In at least one embodiment of the present invention, the color layer is made of at least one of carbon black, titanium oxide, cobalt black, cobalt sulfide, copper chromium black, iron chromium black, aniline black, nickel oxide, iron oxide, aluminum oxide, tin oxide, lead sulfate, lead chromate, calcium carbonate, and silicon oxide.

In at least one embodiment of the present invention, the material of the colored layer further includes a fluoropolymer.

In at least one embodiment of the present invention, the average reflectivity of the back plate in the visible light range is less than 10%.

In at least one embodiment of the present invention, the refractive index of the connection layer is less than or equal to the refractive index of the encapsulant.

In at least one embodiment of the present invention, the photovoltaic elements are projected on the back plate along a normal of the back plate to form a plurality of covering areas, and the light reflecting portions are respectively limited in the covering areas.

In at least one embodiment of the present invention, the light-reflecting portions are regularly arranged.

In at least one embodiment of the present invention, the thickness of each light reflecting portion is greater than or equal to 2 μm.

In at least one embodiment of the present invention, the at least one light reflecting portion includes at least one light reflecting member, and the shape of the light reflecting member is a cylinder or a cone.

In at least one embodiment of the present invention, the length, the width and the height of the light reflecting member are all greater than or equal to 2 micrometers.

In at least one embodiment of the present invention, the light reflecting portions include a plurality of light reflecting members, and the light reflecting members of the same light reflecting portion are separated from each other.

In at least one embodiment of the present invention, the light reflecting portions include a plurality of light reflecting members, and the light reflecting members of the same light reflecting portion are connected to each other.

In at least one embodiment of the present invention, the light-reflecting portions are a plurality of light-reflecting films.

In at least one embodiment of the present invention, the material of the light reflecting portions includes at least one of titanium oxide, tin oxide, barium sulfate, silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, aluminum silicate, and magnesium silicate.

Based on the above, since the average reflectivity of each light reflecting portion in the wavelength range of 300 nm to 1200 nm is greater than or equal to 50%, the light reflecting portions can reflect light to increase the light incident on the photovoltaic elements. In this way, the light reflecting portions can help maintain or improve the generated power of the solar module even in the case that the color of the back sheet is not favorable for the generated power.

The invention is described in detail below with reference to the drawings and specific examples, but the invention is not limited thereto.

Drawings

Fig. 1A is a schematic perspective view of a solar module according to at least one embodiment of the invention.

FIG. 1B is a schematic cross-sectional view taken along line 1B-1B in FIG. 1A.

FIG. 1C is a broken line diagram illustrating the reflectivity of both the backplane of FIG. 1B and the conventional black backplane as a function of wavelength.

Fig. 1D is a schematic top view of the back plate and the light reflecting portion in fig. 1B.

FIG. 1E is a schematic top view of the reflector of FIG. 1B.

Fig. 2 is a schematic top view of a reflector in various other embodiments of the invention.

Fig. 3 is a schematic cross-sectional view of a reflector in various other embodiments of the invention.

Fig. 4 is a schematic cross-sectional view of a solar module according to another embodiment of the present invention.

Fig. 5 is a schematic cross-sectional view of a solar module according to another embodiment of the present invention.

Wherein, the reference numbers:

100. 400 and 500: solar module

110: back plate

111: coloured layer

112: light reflecting plate

113: protective layer

120: connecting layer

130: packaging material

131: a first encapsulation layer

132: second packaging layer

140: transparent plate

150: photovoltaic element

151: first surface

152: second surface

153: side edge

159: conducting wire

160. 460, 560: light reflecting part

161. 201, 202, 301, 302, 303: reflecting piece

161a, 202 a: width of

161b, 202 b: length of

161 h: thickness of

190: terminal box

201 r: diameter of

C11, C12: digital line

L11, L12, L13, L14: light ray

N1: normal line

R15: covering area

Detailed Description

The invention will be described in detail with reference to the following drawings, which are provided for illustration purposes and the like:

in the following description, the dimensions (e.g., length, width, thickness, and depth) of elements (e.g., layers, films, substrates, regions, etc.) in the figures are exaggerated in various proportions for the sake of clarity. Accordingly, the following description and illustrations of the embodiments are not limited to the sizes and shapes of elements shown in the drawings, but are intended to cover deviations in sizes, shapes and both that result from actual manufacturing processes and/or tolerances. For example, the flat surfaces shown in the figures may have rough and/or non-linear features, while the acute angles shown in the figures may be rounded. Therefore, the elements shown in the drawings are for illustrative purposes only, and are not intended to accurately depict the actual shapes of the elements or to limit the scope of the claims.

Furthermore, the terms "about", "approximately" or "substantially" as used herein encompass not only the explicitly recited values and ranges of values, but also the allowable range of deviation as understood by those of ordinary skill in the art, wherein the range of deviation can be determined by the error in measurement, for example, due to limitations of both the measurement system and the process conditions. Furthermore, "about" can mean within one or more standard deviations of the above-described values, e.g., within ± 30%, 20%, 10%, or 5%. The terms "about," "approximately," or "substantially," as used herein, may be selected with an acceptable range of deviation or standard deviation based on optical, etching, mechanical, or other properties, and not all such properties may be applied with one standard deviation alone.

Fig. 1A is a schematic perspective view of a solar module according to at least one embodiment of the invention, and is also an exploded schematic view of the solar module 100, so that the elements of the solar module 100 shown in fig. 1A are separated from each other and are not combined. Referring to fig. 1A, the solar module 100 includes a back plate 110, a packaging material 130, a plurality of photovoltaic devices 150, and a transparent plate 140, wherein the packaging material 130 is disposed on the back plate 110, and the transparent plate 140 is disposed on the packaging material 130. The transparent plate 140 is, for example, a glass plate or a transparent plastic plate.

The photovoltaic elements 150 are disposed within the encapsulant 130. Specifically, the encapsulant 130 has a multi-layer structure, and the photovoltaic elements 150 are disposed between two of the multi-layer structure. Taking fig. 1A as an example, the packaging material 130 may include two packaging layers: a first encapsulation layer 131 and a second encapsulation layer 132. The first encapsulation layer 131 is disposed on the back sheet 110, and the second encapsulation layer 132 is disposed on the first encapsulation layer 131, wherein the photovoltaic elements 150 are disposed between the first encapsulation layer 131 and the second encapsulation layer 132.

Both the first packaging layer 131 and the second packaging layer 132 can be made of polymer materials, wherein the materials of the first packaging layer 131 and the second packaging layer 132 can be the same or different. For example, the first and second encapsulation layers 131 and 132 may both be made of Ethylene-Vinyl Acetate (EVA). Since both the first and second encapsulation layers 131 and 132 may be the same in constituent material, the first and second encapsulation layers 131 and 132 may have the same refractive index.

However, even if both the first and second encapsulation layers 131 and 132 include the same polymer material, both the first and second encapsulation layers 131 and 132 may have refractive indices different from each other. For example, when the first and second encapsulation layers 131 and 132 are made of ethylene-vinyl acetate copolymer (EVA), air or other materials, such as glass particles, may be mixed into the interior of one of the first and second encapsulation layers 131 and 132. As such, although both the first encapsulation layer 131 and the second encapsulation layer 132 include the same material, they may have different refractive indices.

The photovoltaic device 150 may be made of a semiconductor material, such as silicon. The photovoltaic elements 150 may have wires 159, wherein the wires 159 may be solder strips formed by solder, and the photovoltaic elements 150 may be electrically connected to each other, for example, in series with the photovoltaic elements 150, so as to increase the voltage output by the solar module 100.

The solar module 100 may further include a junction box 190, wherein the junction box 190 may be disposed below the back sheet 110. Therefore, the back sheet 110 may be disposed between the encapsulation material 130 and the junction box 190. The junction box 190 may have a plurality of cables (not shown) that electrically connect the photovoltaic elements 150. By using these cables, the junction box 190 can output the electric energy generated by the solar module 100 for the external electronic device or the power system.

Fig. 1B is a schematic cross-sectional view taken along the line 1B-1B after the back sheet 110, the encapsulant 130, the photovoltaic elements 150 and the transparent plate 140 are combined in fig. 1A, wherein the junction box 190 and the wires 159 are omitted in fig. 1B. Referring to fig. 1A and 1B, the first packaging layer 131 is fixed on the back plate 110, wherein the first packaging layer 131 can be adhered to the back plate 110. Taking fig. 1B as an example, the solar module 100 includes a connection layer 120, which may be a transparent adhesive material. The connection layer 120 is disposed on the back plate 110, and the first encapsulation layer 131 of the encapsulation material 130 is disposed on the connection layer 120.

The connection layer 120 may have adhesiveness, so that the connection layer 120 can adhere the first encapsulation layer 131 and the back plate 110. The material of the connection layer 120 may include at least one of polyolefins, acrylics, silicones, urethanes, polyvinyl butyrals, ethylene glycol monoethyl ether acetate, and fluoropolymers. In other words, the material of the connecting layer 120 may be selected from the group consisting of polyolefins, acrylics, silicones, urethanes, polyvinyl butyral, ethylene glycol monoethyl ether acetate, and fluoropolymers, i.e., the material of the connecting layer 120 may be any combination thereof. For example, the connecting layer 120 may be formed of a material including only the silicone silanes or the silicone silanes and the fluoropolymer.

Examples of the Polyolefin include ethylene-vinyl acetate copolymer (EVA), Polyolefin Elastomer (POE), polyethylene, and polypropylene. The acrylic resin is, for example, methyl methacrylate, butyl methacrylate or n-butyl acrylate. Examples of the silicone silane include Polydimethylsiloxane (PDMS). The fluorine-containing polymer is, for example, a fluoroacrylate monomer (FA), dodecafluoroheptyl methacrylate (DFMA), chlorotrifluoroethylene, hexafluoropropylene, polyvinyl fluoride, polyvinylidene fluoride, ethylene-tetrafluoroethylene copolymer, polytetrafluoroethylene, or perfluoroethylene-propylene copolymer.

The back plate 110 includes a colored layer 111 and a reflective plate 112, wherein the colored layer 111 is formed on the reflective plate 112. The light reflecting plate 112 may be a white plate, which may be made of a polymer material. For example, the light reflection plate 112 may be a white plate made of Polyethylene Terephthalate (PET). In addition, the light reflecting plate 112 may also be a metal plate, so the light reflecting plate 112 is not limited to a plate made of a polymer material. Since the reflective plate 112 can be a white plate or a metal plate, the reflective plate 112 can reflect light, wherein the reflective plate 112 can reflect not only visible light but also infrared light.

The color of the colored layer 111 may be black, blue, green, red, or other colors. Alternatively, the colored layer 111 may also include at least two colors so that the appearance of the solar module 100 may exhibit a variety of colors. When the color of the colored layer 111 is black, the material of the colored layer 111 may include at least one of carbon black, titanium oxide, cobalt black, cobalt sulfide, copper chromium black, iron chromium black, aniline black, nickel oxide, iron oxide, aluminum oxide, tin oxide, lead sulfate, lead chromate, calcium carbonate, and silicon oxide.

In other words, the black colored layer 111 may be made of a material selected from the group consisting of carbon black, titanium oxide, cobalt black, cobalt sulfide, copper chromium black, iron chromium black, aniline black, nickel oxide, iron oxide, aluminum oxide, tin oxide, lead sulfate, lead chromate, calcium carbonate, and silicon oxide, i.e., the black colored layer 111 may be made of any combination of the above materials. For example, the black colored layer 111 may include carbon black and titanium oxide, or only nigrosine or iron oxide. The material constituting the colored layer 111 may further include the above-mentioned fluorine-containing polymer, such as a fluoroacrylate monomer (FA), dodecafluoroheptyl methacrylate (DFMA), chlorotrifluoroethylene, hexafluoropropylene, polyvinyl fluoride, polyvinylidene fluoride, ethylene-tetrafluoroethylene copolymer, polytetrafluoroethylene, or perfluoroethylene-propylene copolymer.

The back plate 110 may further include a protective layer 113, wherein the protective layer 113 is disposed on the reflective plate 112, and the reflective plate 112 is disposed between the protective layer 113 and the colored layer 111. The material of the protective layer 113 may include a fluorine-based material, such as Polyvinyl Fluoride (PVF), Polyvinylidene Fluoride (PVDF), an Ethylene Tetrafluoroethylene (ETFE), or Polytetrafluoroethylene (PTFE), which is commonly referred to as teflon. The fluorine-based material has good weather resistance and ultraviolet light resistance, and thus can effectively protect the solar module 100, so that the solar module 100 is suitable for operating in an outdoor environment.

FIG. 1C is a broken line diagram illustrating the reflectivity of both the backplane of FIG. 1B and the conventional black backplane as a function of wavelength. Referring to fig. 1B and 1C, a line C11 in fig. 1C represents the reflectivity of the back plate 110, and the reflectivity of a line C11 is measured from the colored layer 111 to the back plate 110, wherein the line C11 is drawn by measuring the reflectivity of the back plate 110 under the condition that the color of the colored layer 111 is black. Line C12 represents the reflectivity of a conventional black back sheet for a solar module, wherein the conventional black back sheet is a plate with a completely black surface.

As can be seen from the line C11 in fig. 1C, the average reflectivity of the backsheet 110 is greater than 0 in the wavelength range of 500 nm to 1200 nm, wherein the average reflectivity of the backsheet 110 is greater than 20% in the wavelength range of 500 nm to 1200 nm. Secondly, since the reflective plate 112 can reflect infrared light, the average reflectivity of the back plate 110 in the infrared light range (about 1000 nm to 1200 nm) can be significantly greater than 20% under the condition that the colored layer 111 is black. However, the average reflectivity of the back plate 110 in the visible light range (about 380 nm to 750 nm) is less than 10%, so under the condition that the color of the colored layer 111 is black, the back plate 110 can reflect more infrared light and less visible light.

In contrast, the average reflectivity of the conventional black back plate in the wavelength range of 500 nm to 1200 nm is substantially equal to zero, and the reflectivity of the conventional black back plate in the infrared light range (about 1000 nm to 1200 nm) is relatively close to zero as seen from the line C12 in fig. 1C. Therefore, the conventional black back plate is difficult to reflect visible light and infrared light. Thus, the backplane 110 has a significantly higher reflectivity than conventional black backplanes at wavelengths in the range of 500 nm to 1200 nm.

Fig. 1D is a schematic top view of the back plate and the light reflecting portion in fig. 1B. Referring to fig. 1B and fig. 1D, the solar module 100 further includes a plurality of light-reflecting portions 160, wherein the light-reflecting portions 160 are disposed on the colored layer 111 of the back plate 110 and are separated from each other, and the connecting layer 120 covers the light-reflecting portions 160. In addition, the thickness 161h of each light reflecting part 160 may be greater than or equal to 2 micrometers, and the thickness 161h may be less than the thickness of the connection layer 120, so that the light reflecting part 160 does not penetrate the connection layer 120. In addition, in other embodiments, thickness 161h may also be less than 2 microns, so thickness 161h is not limited to being greater than or equal to 2 microns.

The average reflectance of each light reflecting portion 160 in the wavelength range of 300 nm to 1200 nm may be greater than or equal to 50%, so the light reflecting portion 160 can reflect not only visible light but also infrared light. The material of the light reflecting portion 160 may include at least one of titanium oxide, tin oxide, barium sulfate, silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, aluminum silicate, and magnesium silicate. That is, the material of the light reflecting portion 160 may be selected from the group consisting of titanium oxide, tin oxide, barium sulfate, silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, aluminum silicate, and magnesium silicate, that is, the material of the light reflecting portion 160 may be any combination of the above materials.

The photovoltaic elements 150 respectively cover the light reflecting portions 160. Taking fig. 1B as an example, the photovoltaic elements 150 can be projected on the back sheet 110 along the normal N1 of the back sheet 110 to form a plurality of covering regions R15, and the light reflecting portions 160 are respectively limited in the covering regions R15. In other words, each light reflecting portion 160 is limited within one covering region R15 and does not exceed the covering region R15.

The photovoltaic elements 150 are aligned with the light reflecting portions 160, respectively, and in the aligned photovoltaic elements 150 and light reflecting portions 160, the light reflecting portions 160 do not protrude from the side edges 153 of the photovoltaic elements 150, as shown in fig. 1B and 1D. In addition, the light reflecting portions 160 and the photovoltaic elements 150 may be arranged regularly. For example, in the embodiment shown in fig. 1D, the light reflectors 160 and the photovoltaic elements 150 may be arranged in an array. However, in other embodiments, the light reflecting portions 160 and the photovoltaic elements 150 may be arranged in other manners besides an array, even in an irregular manner, so that fig. 1D does not limit the arrangement manner of the light reflecting portions 160 and the photovoltaic elements 150.

The at least one reflector 160 comprises at least one reflector 161, wherein the reflector 161 may be in the shape of a cone, such as a pyramid (pyramid) or a cone (cone). In the present embodiment, each light reflecting portion 160 includes a plurality of light reflecting members 161, wherein the light reflecting members 161 may be formed by printing a plurality of times. For example, in the method of forming the reflective member 161, screen printing may be performed to form a thin film on the back plate 110. The film is then cured, wherein the curing may be performed using microwaves. Then, screen printing is performed again to form another new film on the cured film. The new film is then cured. Thereafter, the above steps are repeated until the light reflecting member 161 is completed.

The light reflecting members 161 of the same light reflecting portion 160 are connected to each other. As shown in fig. 1B and 1D, each light reflecting portion 160 may include nine light reflecting members 161 arranged in a 3 × 3 matrix, and the nine light reflecting members 161 are connected to each other. Since the reflectors 160 are confined within one of the cover regions R15, the reflectors 161 do not fall outside the cover region R15, nor on the boundary of the cover region R15.

When external light rays L11, L12, L13 and L14, such as sunlight, are incident to the solar module 100 from the transparent plate 140, the back plate 110 and the light reflecting portions 160 can reflect the light rays L11 to L14 to the photovoltaic elements 150, so that the photovoltaic elements 150 can absorb the light rays L11 to L14 and convert the light rays L11 to L14 into electric energy. In addition, the wavelength ranges of the light beams L11 to L14 not only cover visible light (about 380 nm to 750 nm), but also cover infrared light (about 1000 nm to 1200 nm). Therefore, the light beams L11 to L14 include visible light and invisible infrared light.

After the light L11 and the light L12 enter the solar module 100 from the transparent plate 140, the light L11 and the light L12 sequentially penetrate the transparent plate 140 and the encapsulant 130. The transparent plate 140 may have a refractive index greater than or equal to the refractive index of the encapsulation material 130. For example, in a case where the transparent plate 140 is a glass plate and the encapsulation material 130 is made of ethylene-vinyl acetate copolymer (EVA), the refractive index of the transparent plate 140 may be about 1.5, and the refractive index of the encapsulation material 130 may be about 1.48, which is smaller than the refractive index of the transparent plate 140.

When the light rays L11 and L12 pass through the interface between the transparent plate 140 and the encapsulant 130, the light rays L11 and L12 are deflected (deflected) and deviate from the normal N1 of the back plate 110. Then, the light L11 and L12 enter the connection layer 120 from the encapsulant 130. The refractive index of the connection layer 120 may be smaller than or equal to that of the encapsulant 130, so when the light rays L11 and L12 pass through the interface between the encapsulant 130 and the connection layer 120, the light rays L11 and L12 deviate from the normal N1. Then, the light beams L11 and L12 are incident on the back plate 110.

The back plate 110 can reflect a portion of the light L11 and a portion of the light L12, particularly infrared light in both the light L11 and the light L12, so that the back plate 110 can absorb a portion of the light L11 and the light L12, and the light L11 and the light L12 cannot be totally reflected. After being reflected by the back sheet 110, the light L12 is incident on the second surface 152 of the photovoltaic element 150, and is absorbed by the photovoltaic element 150.

The photovoltaic device 150 has a first surface 151 and a second surface 152, wherein the first surface 151 is opposite to the second surface 152, and the photovoltaic device 150 can absorb light from the first surface 151 and the second surface 152 to generate electric energy. Thus, when the photovoltaic element 150 absorbs the light L12 from the second surface 152, the photovoltaic element 150 can convert the light L12 into electrical energy.

The light L11 is reflected by the back plate 110 and then incident on the interface between the transparent plate 140 and the encapsulant 130. Then, a portion of the light L11 is reflected by the interface between the transparent plate 140 and the encapsulant 130. A portion of the light L11 reflected by the interface between the transparent plate 140 and the encapsulant 130 is incident on the first surface 151 of the photovoltaic device 150. Thus, the photovoltaic device 150 can absorb the light L11 and convert the light L11 into electrical energy.

After the light rays L13 and L14 enter the solar module 100 from the transparent plate 140, the light rays L13 and L14 also sequentially penetrate the transparent plate 140 and the encapsulant 130, wherein the interface between the transparent plate 140 and the encapsulant 130 can also deflect the light rays L13 and L14, so that the light rays L13 and L14 are deviated from the normal N1 of the back plate 110, thereby increasing the probability that the light rays L13 and L14 enter the first encapsulant layer 131.

After the deflected light beams L13 and L14 enter the first encapsulant layer 131, the light beams L13 and L14 are incident on the connecting layer 120. Since the refractive index of the connection layer 120 is less than or equal to the refractive index of the encapsulant 130, the light beams L13 and L14 are deflected by the interface between the encapsulant 130 and the connection layer 120 and deviate from the normal N1, thereby increasing the incidence rate of the light beams L13 and L14 on the light reflection portion 160.

When the light beams L13 and L14 are incident on the light-reflecting portion 160, the light-reflecting portion 160 can reflect the light beams L13 and L14. Since the average reflectivity of the light reflecting portion 160 in the wavelength range of 300 nm to 1200 nm is greater than or equal to 50%, the light reflecting portion 160 can substantially reflect the visible light and the infrared light in both the light rays L13 and L14. The light L13 and the light L14 reflected by the light reflecting portion 160 penetrate through the connection layer 120 and enter the first encapsulant layer 131, wherein the light L14 enters the second surface 152 and is absorbed by the photovoltaic device 150. In this way, the photovoltaic device 150 can convert the light L14 into electrical energy.

The light L13 is reflected by the light reflecting portion 160 and then enters the interface between the transparent plate 140 and the encapsulant 130. Then, a portion of the light L13 is reflected by the interface between the transparent plate 140 and the encapsulant 130. A part of the light L13 reflected by the interface is incident on the first surface 151 of the photovoltaic element 150. In this way, the photovoltaic element 150 can absorb the light L13 and convert the light L13 into electrical energy.

Therefore, the light reflecting portions 160 can reflect light (for example, light L11 to light L14) to increase the light absorbed by the photovoltaic elements 150, so as to increase the power generated by the solar module 100. To sum up, the back plate 110 has a low reflectivity due to the color, so that it is difficult for the back plate 110 to reflect more light to the photovoltaic device 150, and the light reflecting portions 160 can also reflect light to increase the light absorbed by the photovoltaic device 150, thereby helping to increase the power generation of the solar module 100. In other words, the light-reflecting portions 160 can substantially reduce or avoid the adverse effect of the color of the back plate 110 on the generated power, so that the light-reflecting portions 160 can maintain a certain generated power or increase the generated power under the condition that the color of the back plate 110 can be freely selected.

In addition, the reflective plate 112 may allow the back plate 110 to reflect infrared light. Therefore, even if the colored layer 111 has a very low reflectivity (e.g., the black colored layer 111) due to the color, the reflective plate 112 can reflect the infrared light in the external light, so that the photovoltaic elements 150 can absorb more infrared light, thereby increasing the power generation efficiency of the solar module 100

FIG. 1E is a schematic top view of the reflector of FIG. 1B. Referring to fig. 1B and fig. 1E, in the present embodiment, the shape of the light-reflecting member 161 may be a cone. For example, the shape of the reflector 161 may be pyramidal, so that the bottom surface of the reflector 161, i.e., the area occupied by the reflector 161 on the back plate 110, may be substantially rectangular, such as square (as shown in fig. 1E). The width 161a, length 161B, and height of the light reflecting member 161 may be greater than or equal to 2 microns, wherein the height of the light reflecting member 161 is equal to the thickness 161h shown in fig. 1B.

Since the width 161a, the length 161b and the height of the light-reflecting members 161 are greater than or equal to 2 μm, the light-reflecting members 161 substantially do not diffract visible light. However, the wavelength range of the infrared light generally covers 2 microns, so that the light reflecting members 161 can diffract the infrared light with a wavelength of about 2 microns or nearby under the condition that the width 161a, the length 161b and the height (i.e., the thickness 161h) of the light reflecting members 161 are equal to or close to 2 microns.

However, even if the reflectors 161 can diffract infrared light, the reflectors 161 can still make light (e.g., light L11-L14) incident on the photovoltaic elements 150. Even if the light-reflecting member 161 can diffract light (including visible light and infrared light), the overall generated power of the solar module 100 is not adversely affected. Therefore, the width 161a and the length 161b of the reflector 161 can also be smaller than 2 microns, and the reflector 161 with the width 161a and the length 161b both smaller than 2 microns can still make the photovoltaic device 150 absorb more light, so that the overall power generation of the solar module 100 is not reduced.

In the embodiment shown in fig. 1E, the bottom surface of the light reflecting element 161 may be substantially rectangular (e.g., square), but in other embodiments, the bottom surface of the light reflecting element 161 may also be substantially circular or polygonal except rectangular, such as the

light reflecting elements

201 and 202 shown in fig. 2. Please refer to fig. 2. The at least one reflector 161 in the solar module 100 may be replaced with the

reflector

201 or 202 in fig. 2. That is, the solar module 100 may include at least one of the

light reflecting members

201 and 202. For example, the solar module 100 may include the

light reflecting members

161, 201, and 202. Alternatively, the solar module 100 includes a plurality of reflectors 201, but does not include the

reflectors

161 and 202.

The shape of the bottom surface of the reflector 201 may be substantially circular, while the shape of the bottom surface of the reflector 202 may be substantially polygonal, such as hexagonal as shown in fig. 2. In the embodiment shown in fig. 2, the diameter 201r of the bottom surface of the reflector 201 may be greater than or equal to 2 microns, and both the width 202a and the length 202b of the reflector 202 may be greater than or equal to 2 microns. In other embodiments, the diameter 201r, the width 202a and the length 202b may be less than 2 microns, so the diameter 201r, the width 202a and the length 202b are not limited to be greater than or equal to 2 microns. In addition, the constituent materials and forming methods of the

light reflectors

201 and 202 may be the same as those of the light reflector 161.

In the embodiment shown in fig. 1B, each light reflector 161 may be in the shape of a cone, such as a pyramid. However, in other embodiments, for example, the three

reflectors

301, 302 and 303 shown in fig. 3 are all cylindrical instead of the cone shown in fig. 1B. Referring to fig. 3, at least one of the

reflectors

301, 302, and 303 shown in fig. 3 may replace at least one of the reflectors 161 in fig. 1B. That is, the solar module 100 shown in fig. 1B may include at least one of the

light reflectors

301, 302, and 303.

The light reflecting member 301 is substantially a cylinder with a circular top surface, the light reflecting member 302 is substantially a cube or a cylinder, and the light reflecting member 303 is substantially a cylinder with a roof-shaped top surface. In addition, in addition to the

reflectors

301, 302 and 303 shown in fig. 3, the reflectors in other embodiments may have other shapes such as a cylinder with other shapes, for example, a Frustum (Frustum). Therefore, the shape of the light reflecting member is not limited to fig. 1B and 3. In addition, the constituent materials and forming methods of the

light reflecting members

301, 302, and 303 may be the same as those of the light reflecting member 161.

Fig. 4 is a schematic cross-sectional view of a solar module according to another embodiment of the present invention. Referring to fig. 4, the solar module 400 shown in fig. 4 is similar to the solar module 100 described above. For example, the solar module 400 also includes a plurality of light reflecting portions 460, and the light reflecting portions 460 also include a plurality of light reflectors 161. However, the only difference from the solar module 100 is that: in the solar module 400 shown in fig. 4, the light reflecting members 161 of the same light reflecting portion 460 are separated from each other without being connected and without contacting.

It should be noted that in the solar module 400 shown in fig. 4, at least one of the reflectors 161 may be replaced with the

reflector

201 or 202 shown in fig. 2, or the

reflector

301, 302 or 303 shown in fig. 3. Therefore, the shape of the light reflecting member 161 shown in fig. 4 may be a cylinder, and is not limited to a cone (e.g., pyramid). In addition, the at least one light reflecting portion 460 may also include at least one of the

light reflecting members

201, 202, 301, 302, and 303. For example, the single light reflecting portion 460 includes the

light reflecting members

201 and 202. Alternatively, the single light reflecting portion 460 includes the

light reflecting members

301, 302, and 303. Therefore, the light reflecting portion 460 shown in fig. 4 is not limited to include only the light reflecting member 161.

Fig. 5 is a schematic cross-sectional view of a solar module according to another embodiment of the present invention. Referring to fig. 5, the solar module 500 shown in fig. 5 is similar to the solar module 100 described above. For example, the solar module 500 also includes a plurality of light reflecting portions 560, which are also made of the same material as the light reflecting portions 160. However, unlike the solar module 100, the light reflecting portions 560 are a plurality of light reflecting films, and the thickness thereof may be less than 2 μm. The light reflecting portions 560 may be formed by printing, such as screen printing or ink jetting. When the light reflecting part 560 is formed using multiple printing, the light reflecting part 560 may have a thick thickness, even more than 2 μm. Therefore, the light reflecting portion 560 may be 2 μm or more.

It is particularly mentioned that at least one of the light reflecting portions 160 in fig. 1B or 460 in fig. 4 may be replaced by the light reflecting portion 560 shown in fig. 5. In other words, the

solar module

100 or 400 may further include at least one light reflecting portion 560 shown in fig. 5, and at least two of the

light reflecting portions

160, 460 and 560 may be disposed on the same back plate 110.

In the solar module 500 shown in fig. 5, at least one light reflecting part 560 may be replaced with at least one of the

light reflecting members

161, 201, 202, 301, 302 and 303, so that the solar module 500 may include only one light reflecting member (e.g., the

light reflecting member

161, 201, 202, 301, 302 or 303) or a plurality of light reflecting members. It is understood that the

solar modules

100, 400 and 500 disclosed in the above embodiments may include multiple light reflecting portions or multiple light reflecting members, and are not limited to include only the same light reflecting portion and light reflecting member.

In summary, since the light-reflecting portions can reflect light, the light-reflecting portions can increase the light incident on the photovoltaic elements, so as to increase the power generation power. Thus, even under the condition that the color of the back plate is not beneficial to generating power, the light reflecting parts can help to maintain or improve the generating power of the solar module. In other words, the light reflecting portions can maintain a certain power generation power or increase the power generation power, so that the color of the back plate can be freely selected, and the visual effect and the aesthetic feeling of the solar module on the appearance can be improved.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it should be understood that various changes and modifications can be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A solar module, comprising:

a back plate having an average reflectance of greater than 0 at a wavelength in the range of 500 nm to 1200 nm;

a plurality of light-reflecting portions disposed on the back plate, wherein the light-reflecting portions are separated from each other, and an average reflectivity of each light-reflecting portion in a wavelength range of 300 nm to 1200 nm is greater than or equal to 50%;

the connecting layer is arranged on the back plate and covers the light reflecting parts;

a packaging material disposed on the connection layer;

a plurality of photovoltaic elements arranged in the packaging material, wherein the photovoltaic elements respectively cover the light reflecting parts; and

a transparent plate disposed on the packaging material.

2. The solar module of claim 1, wherein the backsheet comprises:

a reflector; and

a color layer formed on the reflector, wherein the light reflecting portions are disposed on the color layer.

3. The solar module of claim 2 wherein the backsheet has an average reflectivity of greater than 20% at a wavelength in the range of 500 nm to 1200 nm.

4. The solar module of claim 2 wherein the colored layer is black in color.

5. The solar module of claim 2, wherein the color layer is formed from a material including at least one of carbon black, titanium oxide, cobalt black, cobalt sulfide, copper chromium black, iron chromium black, aniline black, nickel oxide, iron oxide, aluminum oxide, tin oxide, lead sulfate, lead chromate, calcium carbonate, and silicon oxide.

6. The solar module of claim 5 wherein the material of construction of the colored layer further comprises a fluoropolymer.

7. The solar module of claim 2 wherein the backsheet has an average reflectivity of less than 10% in the visible range.

8. The solar module of claim 1, wherein the refractive index of the connecting layer is less than or equal to the refractive index of the encapsulant material.

9. The solar module as claimed in claim 1, wherein the photovoltaic elements are projected on the back sheet along a normal line of the back sheet to form a plurality of covered regions, and the light-reflecting portions are respectively confined in the covered regions.

10. The solar module of claim 1, wherein the light-reflecting portions are arranged in a regular pattern.

11. The solar module of claim 1, wherein the thickness of each of the light-reflecting portions is greater than or equal to 2 μm.

12. The solar module of claim 1, wherein at least one of the reflectors comprises at least one reflector, and the at least one reflector is in the shape of a cylinder or a cone.

13. The solar module of claim 12, wherein the at least one reflector has a length, width and height greater than or equal to 2 microns.

14. The solar module of claim 1, wherein the light-reflecting portions comprise a plurality of light-reflecting members, and the light-reflecting members of the same light-reflecting portion are separated from each other.

15. The solar module of claim 1, wherein the light reflecting portions comprise a plurality of light reflecting members, and the light reflecting members of the same light reflecting portion are connected to each other.

16. The solar module of claim 1, wherein the light-reflecting portions are a plurality of light-reflecting films.

17. The solar module of claim 1, wherein the light-reflecting portions are formed of a material including at least one of titanium oxide, tin oxide, barium sulfate, silicon oxide, aluminum oxide, magnesium oxide, calcium carbonate, aluminum silicate, and magnesium silicate.