Colored solar cells containing effect pigments.

Abstract

The present invention relates to a coloured solar cell or solar cell module comprising two or more transparent front cover layers each containing effect pigments of a different colour, and a method for making same.

Description

[Technical field]

[0001] The present invention relates to a coloured solar cell or solar cell module comprising two or more transparent front cover layers each containing effect pigments of a different colour, and a method for making same. [Background technology]

[0002] Solar cells have enjoyed great success in recent years, with over 600 GW of grid-connected capacity worldwide in 2019, with the majority of this installed at utility scale. The basic function of any solar cell relies on a photoactive material absorbing light and creating excited electron-hole pairs, which are separated within the solar cell by a region of different electron and hole mobilities, the so-called p-n junction. Due to the wide range of light absorbing materials available, many different types of solar cell technologies are known in the photovoltaic industry. 1) Crystalline silicon solar cells (single crystal c-Si and polycrystalline mc-Si) 2) Cadmium telluride solar cells (CdTe) 3) Copper indium gallium diselenide (CIGS / CIS) 4) Amorphous silicon solar cells (a-Si) 5) III / V solar cells, such as gallium arsenide (GaAs) solar cells, or multijunction solar cells made of stacks of elements of groups III and V, such as gallium / indium-(aluminum)-gallium arsenide or phosphide (In(Al)GaAs / P) 6) Dye-sensitized solar cell (DSSC) 7)Organic solar cells (OSC) 8) Perovskite solar cells (PSC) 9) Quantum dot solar cells (QSC) 10) Other II / VI solar cells made of group II and group VI elements such as zinc selenide (ZnSe) or iron sulfide (FeS) 11) Tandem solar cell However, increasing the amount of surface area available for solar energy production, for example on the surfaces of buildings and objects (e.g., automobiles), increases the overall surface area available for solar energy production. Therefore, new technologies and methods to create solar cells with attractive colors and hues, and to increase their efficiency under various angles of incidence, are of great interest to the solar energy industry. For example, by using a rear sealing film with the same color as the solar cell and coloring the conductive part of the solar module / panel, the color impression can be improved. However, color customization may be required by the market or building owner for each building installation. In this case, coloring is complicated and expensive.

[0003] WO 2019 / 122079 discloses a colored solar cell or solar module comprising a layer containing translucent effect pigments. The translucent effect pigments control the color of the light-incident side without compromising the efficiency of the solar panel. The effect pigments reflect a portion of the visible sunlight but allow the light necessary for energy generation to pass through. Since the effect pigments are plate-shaped, the more the ends of the plate-shaped pigments are oriented towards the viewing surface of the solar module, the less their color is reflected. It is therefore preferred that the effect pigments are mainly oriented substantially parallel to the module surface, although some random orientation may be desirable to maintain the color impression related to the viewing angle. The color can be achieved by using a single pigment or a mixture of pigments, for example for the glass color, and applying and curing the front glass, or by extruding a single pigment or a mixture of pigments into an encapsulating polymer film and using the colored polymer film as the front encapsulant of the solar module or device. To customize color, glass colors can be mixed and applied efficiently in small batch sizes, but require additional printing and curing steps, which can be cost-prohibitive. Also, when pigment mixtures are used in large-scale colored solar cell manufacturing processes, colors can vary slightly from batch to batch, and it can be difficult to reproduce the same color in modules that cover a large area. Summary of the Invention

[0004] It is therefore an object of the present invention to provide an improved method for coloring solar cells and solar modules, which does not have the drawbacks of prior art methods, is capable of coloring solar cells in a variety of customized colors, provides uniform color appearance of solar cell modules even over large areas, and is suitable for time- and cost-effective large-scale production processes. Another object of the present invention is to provide improved colored solar cells and solar cell modules in which the appearance of customized color is uniform over a wide range. Another object of the present invention is to provide a method that increases the flexibility in creating customized colors and in using colored encapsulant films in solar cells and solar cell modules. Further objects of the present invention will be readily apparent to those skilled in the art from the following description and examples.

[0005] Surprisingly, it has been found that one or more of these objectives may be achieved by colored solar cells and solar cell modules as disclosed and claimed below, which include two or more different transparent front cover layers, each transparent front cover layer (hereinafter also abbreviated as "TFCL") containing a different color effect pigment. The present application relates to a coloured solar cell or a coloured solar cell module comprising two or more TFCLs, each of said TFCLs containing at least one, and preferably only one, effect pigment having a specific colour and consisting of a transparent or translucent flake-shaped substrate coated with one or more layers of transparent or translucent material and optionally a post-coating, and at least one of the TFCLs containing an effect pigment having a different colour than the effect pigments contained in the other transparent front cover layers. Preferably the TFCL is a seal layer or seal film or a component thereof, or together forms a front seal film or a component thereof. The present application further relates to a process for making a colored solar cell or solar cell module, comprising stacking two or more TFCLs, each containing an effect pigment as described above and below having a particular color, on the front side of the solar cell or solar cell module, wherein at least one of the TFCLs contains an effect pigment having a different color than the effect pigments contained in the other TFCLs. The present invention further relates to the use of the colored solar cells and colored solar cell modules as described above and below in architectural installations or devices, preferably selected from windows, doors, building facades, building roofs or floors, walls, structural glass, curtain walls, showrooms, car roofs, car bodies, mobile phones, portable PCs such as tablets, plug-in solar cell modules, roof tiles, solar panels, photovoltaic (PV) fences, military equipment, radios, wireless equipment, music boxes, power banks, watches, eyeglasses, and goggles. The present invention further relates to a building installation or device comprising one or more colored solar cells or colored solar cell modules as mentioned above and below, said installation or device being preferably selected from windows, doors, building facades, building roofs or floors, walls, structural glass, curtain walls, showrooms, car roofs, car bodies, mobile phones, portable PCs such as tablets, plug-in solar cell modules, roof tiles, solar panels, PV fences, military equipment, walkie-talkies, wireless equipment, music boxes, power banks, watches, eyeglasses, and goggles.

[0006] In the above and below, the term "front side" of a solar cell or solar module means the light-receiving side or the side facing the incident light, and the term "rear side" or "back side" of a solar cell or solar module means the side opposite the radiation-receiving side or facing away from the incident light. The term "front cover layer" or "front encapsulation film" means a layer, sheet, or encapsulation film provided on the front side of a solar cell or solar module. The terms "rear glass / sheet" and "rear encapsulation film" mean a glass, sheet, or encapsulation film provided on the rear side of a solar cell or solar module. Above and below, unless otherwise stated, the term "solar cell" is understood to encompass both single solar cells and solar cell modules, as well as arrays, strings, or patterns of the foregoing. Similarly, the term "solar cell module" is understood to encompass single solar cells, unless otherwise stated. In the foregoing and hereinafter, unless otherwise stated, the weight percentages of light-scattering particles and effect pigments are based on the total weight of the solid part of the layer, sheet or film. In the foregoing and hereinafter, a layer, sheet or film according to the invention, also referred to briefly as "layer", is understood to include a layer, sheet or film according to the invention as described above or below. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is an exemplary schematic diagram of a colored solar cell module according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The present invention provides a highly efficient method for coloring state-of-the-art solar cells or solar cell modules consisting of multiple electrically interconnected solar cells, which is highly flexible, achieves a wide variety of colors with low or negligible loss in solar cell efficiency, and has excellent long-term stability. Furthermore, the present invention provides a solution for achieving a wide variety of customized colors with good batch-to-batch reproducibility and suitability for a wide range of applications. It has thereby surprisingly been found that a wide range of customized colours can be created, for example by applying two or more single TFCLs as front encapsulants, each of said layers containing effect pigments of different individual colours, as a stack of films in a lamination process of a solar module. For example, it has been found that laminating a solar cell with a stack of two or more red / green / blue colored encapsulating polymer films surprisingly results in a uniform gray color after lamination that has a similar color appearance as a single encapsulating polymer film when the corresponding mixture of red / green / blue pigments is added to the polymer melt and co-extruded with the polymer film. However, encapsulating films that contain only one color of effect pigment with a consistent color appearance are easier to reproduce in large batches than films that contain a mixture of effect pigments with different colors. Thus, a wide range of customized colors can be more easily reproduced and batch-to-batch color variations can be more easily reduced by simply laminating films of different colors onto a solar cell module. The method according to the present invention also allows the production of various colors in the process step of laminating the solar cell module, rather than in the process step of film extrusion. Also, when multiple colored sealing films are used, no additional manufacturing steps are required. Instead, solar cell manufacturers only need to replace the non-colored sealing film with two or more colored sealing films, or multiple layers of two or more colored sealing films. Furthermore, since large batch sizes of several tons are typically required to produce colored films cost-effectively, rather than producing large quantities of colored films with specific pigment mixtures for each individual request, it is more efficient to produce multiple colored films in various colors that can be stored and combined in any way to produce the desired color for each individual request from a solar module manufacturer.

[0009] Using two or more layers containing effect pigments, the solar cell front surface appears in various colors obtained by mixing basic colors such as red, green, and blue. In this way, solar module manufacturers can create various colors with only three basic films, e.g. red, green, and blue, on hand. One film extrusion manufacturing step is not required for each color. This solves the problem of simplifying the color production of colored sealing films and avoiding the limitation of single batch size production. Therefore, the production of colored sealing films usually requires a relatively large standard batch size to achieve a certain color and film quality. This batch size is much larger than a single batch size of sealing film required, for example, to cover a solar module of a standard building for an individual project. Therefore, the demands of multiple individual projects can be met with a standard size batch of colored sealing films or sets of films in customized colors, which improves the time and cost efficiency of the production of colored sealing films. Therefore, in the method according to the present invention, it is not necessary to manufacture a film for each color, and various colors can be realized simply by combining colored standard films, which makes it easy to adjust colors. For example, turquoise can be made with a green pigment layer and a blue pigment layer, yellow with a red pigment layer and a green pigment layer, and pink with a red pigment layer and a blue pigment layer. The effect pigments used in the present invention impart color by reflecting light, not absorbing it as traditional dyes and pigments do. Red, green, and blue effect pigments can be selected to have similar light transmission properties, and the transmission values ​​are typically all above 80%. This makes it easier to create accurate colors, even colors like gray, with transmission values ​​above 80%. This is another advantage of using a combination of RGB films.

[0010] The colour combinations, besides selecting the reflection colour of the effect pigments in the individual TFCLs, may be further varied by varying the thickness of the individual layers, and / or by varying the concentration of the effect pigments in the individual layers, and / or by varying the number of individual layers of the same or different colours, e.g. by combining one or more first TFCLs having a first colour with one, two or more second TFCLs having a second colour, and optionally with further TFCLs having further colours. Furthermore, the front cover film can be uniaxially or biaxially stretched or drawn to some extent before or during lamination of the solar module to change the color effect on the surface and create marble-like effects or patterns and structures, which is especially useful for decorating buildings where different color structures are required. In a preferred embodiment of the invention, the coloured solar cell or solar cell module comprises two or more, preferably between two and six, very preferably two, three, four or five, most preferably two or three TFCLs, at least one of which, and preferably each, contains an effect pigment having a colour different from the colours of the effect pigments in the other TFCLs. In another preferred embodiment of the invention the coloured solar cell or solar cell module comprises two or more, preferably two, three, four or five TFCLs, at least one of which, preferably each of which has a different colour from the effect pigments contained in the other TFCLs and contains an effect pigment selected from silver-white, yellow, red, green and blue effect pigments respectively. Since the effect pigments exhibit a characteristic color by reflection of light, the color effect is particularly visible against a dark or black background. Thus, preferably, the colored solar cell or colored solar cell module according to the invention comprises a black or dark (e.g. deep blue) rear sheet, e.g. a black or dark rear sealing sheet or film.

[0011] In typical applications, the concentration of effect pigments in TFCL is 1 g / m 2 Below 1 g / m, the color impression may already be strong, but the solar cell structure may still be visible, so preferably2 In addition to the high hiding power, the angle dependency of the color of the solar cell module is reduced. The combination of two or more basic colors, such as red, green and / or blue, opens up new possibilities for designing colored solar cell modules with individual customized colors from a wide range of options. It has also been found that stacking TFCLs, each containing a different color effect pigment, is ideal for providing sufficient color without significantly reducing the overall solar cell efficiency. Long-term tests have shown high stability. Since the direct contact between the effect pigment-containing layer and the solar cell is the most demanding part of the construction of a solar module, it can be safely assumed that the effect pigment-containing layer can be used at any other position in the solar module stack without any adverse effects. Effect pigments reflect some of the incident visible light but allow the light needed for photovoltaic energy generation to pass through. Effect pigments can be oriented to modify the angle at which they are most efficient, thereby manipulating color and efficiency. Layers containing effect pigments can be easily applied to state-of-the-art solar cells making their application more efficient. The process steps of applying layers containing effect pigments to solar cell modules can be easily integrated into existing state-of-the-art processes for manufacturing encapsulated solar cell modules.

[0012] The use of the present invention allows the appearance of the solar cell to be adapted to specific needs. The appearance of objects containing solar cells, such as buildings, equipment, and automobiles, can be improved, and the transparency and reflectance of the solar cell can be controlled. Furthermore, the use of a dark backsheet and darkening of the busbars and connection points can reduce or avoid the visibility of the cells and light-colored busbars. The present invention can also be used to impart special colors to the solar cells to achieve special effects and designs. For example, textures can also be added depending on the effect pigments used, for example to add a gloss effect to the panel, to imitate a brick wall, or to add color to various surfaces of materials used in house construction. Another advantage of the present invention is that it allows the seamless integration of solar cells into any surface by changing its appearance to a familiar and normal appearance that people are accustomed to, such as the surfaces of buildings (facades and roofs), handheld, portable and stationary devices, automobiles and other vehicles (cars, trucks, motorcycles, scooters, trains, boats, trailers, etc.), price tags, plastic products, wearable products, and household appliances, or other highly visible surfaces where seamless integration of solar cells or other types of solar cell installation is required without changing the optical appearance, where the normal technical appearance of the solar cell is changed to a familiar and normal appearance that people are accustomed to, and where long term stability is essential. Furthermore, currently available technologies have a major drawback in terms of their impact on solar cell performance, which can drop from an initial performance of over 15% to less than 10% under real-life conditions, whereas the efficiency of colored solar cells is not affected as significantly, and therefore the cost of solar power generation is not significantly increased. Coloring of solar cells according to the present invention is possible in a wide variety of colors and is not limited to rigid substrates such as glass or to single solar cell technology.

[0013] The effect pigments in the TFCL according to the present invention are preferably selected from pearlescent pigments, interference pigments, and multilayer pigments. In a preferred embodiment of the invention, the effect pigments are selected from interference pigments. The optical effect of interference pigments is based on the difference in refractive index of materials arranged one on top of the other in the pigment in the form of thin layers, which reflect, transmit and possibly absorb incident light differently depending on the refractive index of each layer and the medium surrounding the interference pigment. The difference in refractive index between adjacent layers causes reflected light rays to take different paths and interfere with each other, thereby selectively amplifying or attenuating certain wavelengths of light. The reflected light rays in the visible wavelength range thus amplified are perceived by an observer under appropriate conditions as visible interference colors. If all layers of an interference pigment are made of colorless and transparent materials, only the interference colors of the interference pigments are perceived, and not the masstones. Optically, the interference colors of interference pigments that have no absorption color behave like colored rays, i.e. combine additively with each other, so that for example a stack of three TFCLs, each containing a different interference pigment selected from red, green, and blue interference pigments (i.e., interference pigments that exhibit red, green, or blue interference colors in the application medium), will result in a gray or whitish color. Generally, each interference pigment consists of a flake-shaped support and one or more generally transparent layers covering the flake-shaped support. However, the uniform layer thickness of the support and each layer, the homogeneity of the composition and the homogeneity of the surface properties of the support and each layer, as well as the size and size distribution of the pigments, among others, determine to what extent the optical behavior of each interference pigment differs from the ideal behavior of currently used materials. Therefore, the preparation conditions of interference pigments can have a great influence on their optical behavior. Therefore, even interference pigments that have the same formal hue (e.g. red color) and the same formal layer structure (e.g. titanium dioxide layer on mica flakes) may show differences in optical behavior, expressed for example in chroma, brightness or color angle, depending on the manufacturer, the preparation process used, and even from batch to batch. However, these drawbacks can be overcome by using the method according to the present invention, which allows a wide variety of colors to be produced without the need to produce each color in a single film production process, for example by using three basic films with red, green and blue colors, thereby avoiding the limitations of single-batch production.

[0014] The effect pigments are preferably based on synthetic or natural mica, flaky glass substrates, flaky SiO2 substrates or flaky Al2O3 substrates, which are preferably coated with one or more layers of metal oxides and / or metal oxide hydrates of Ti, Sn, Si, Al, Zr, Fe, Cr and Zn. The effect pigments used in the TFCL according to the invention are preferably transparent or at least translucent. The effect pigments useful in the invention preferably exhibit yellow, red, blue or green colors. However, other colors such as gray, white, purple, red or orange are also suitable. Other colors or mixtures thereof to produce specific colors and shades can also be used. The effect pigments can also provide metallic effects such as, but not limited to, silver, platinum, gold, copper, and various other metals. In a preferred embodiment of the invention, each individual TFCL contains only one effect pigment. The effect pigments preferably comprise, and very preferably consist of, a transparent or translucent flake-shaped substrate coated with one or more layers of transparent or translucent material and optionally a post-coat. Preferably, the effect pigments contain a flake-like substrate comprising at least one coating comprising a metal oxide, a metal oxide hydrate, or a mixture thereof. Preferably, the effect pigments consist of a transparent or translucent, colorless flake-like substrate, which is coated with one or more layers of a transparent or translucent, colorless material. Preference is given to using pearlescent pigments, interference pigments, and / or multi-layer pigments. The long-term stability of the effect pigments can preferably be improved by using a post-coating of an organic and / or inorganic coating as the final layer of the effect pigment, as described, for example, in WO 2011 / 095326 and below.

[0015] Suitable substrates for effect pigments are, for example, all known coated or uncoated flake-shaped substrates, preferably transparent or translucent, preferably colorless flakes.For example, phyllosilicates, especially synthetic or natural mica, glass flakes, SiO2 flakes, Al2O3 flakes, TiO2 flakes, liquid crystal polymers (LCP), holographic pigments, BiOCl flakes, or mixtures of said flakes are suitable.Aluminum flakes with dielectric coating can also be used in low concentrations according to the present invention, to obtain very high hiding power of active photovoltaic layer. The glass flakes may consist of any type of glass known to the person skilled in the art, such as, for example, A-glass, E-glass, C-glass, ECR-glass, recycled glass, window glass, borosilicate glass, Duran® glass, laboratory glass, or optical glass. The refractive index of the glass flakes is preferably 1.45 to 1.80, in particular 1.50 to 1.70. Particularly preferred glass flakes consist of A-glass, C-glass, E-glass, ECR-glass, quartz glass, and borosilicate glass. Preference is given to coated or uncoated flakes of synthetic or natural mica, SiO2 flakes, Al2O3 flakes and glass flakes, in particular C-glass, ECR-glass or calcium aluminum borosilicate glass flakes. In particular, the use of effect pigments based on calcium aluminum borosilicate glass is preferred. In a variant of the invention, Al2O3 flakes are preferred. The thickness of the substrate is generally 0.01 to 5 μm, in particular 0.05 to 4.5 μm, and particularly preferably 0.1 to 1 μm. The length or width dimension is usually 1 to 500 μm, preferably 1 to 200 μm, and particularly preferably 5 to 125 μm. They generally have an aspect ratio (ratio of average diameter to average particle thickness) of 2:1 to 25,000:1, preferably 3:1 to 1000:1, and particularly 6:1 to 250:1. The above dimensions of the flake-shaped substrates also apply in principle to the coated effect pigments used according to the invention, since the additional coating is generally in the range of only a few hundred nanometers and does not significantly affect the thickness or length or width (particle size) of the effect pigments. The particle size and particle size distribution of the effect pigments and their substrates can be determined by various methods common in the art, but preferably by laser diffraction in standard methods using a Malvern Mastersizer 2000, Beckman Coulter, Microtrac, etc. In addition, other techniques such as SEM (scanning electron microscope) imaging can also be used.

[0016] In a preferred embodiment, the substrate is coated with one or more transparent or semi-transparent layers comprising a metal oxide, metal oxide hydrate, metal hydroxide, metal suboxide, metal fluoride, metal nitride, metal oxynitride, or mixtures of these materials, preferably partially or completely encased in these layers. Furthermore, effect pigments with a multi-layer structure may also be used, which comprise high and low refractive index layers, and the high and low refractive index layers preferably alternate. Particularly preferred are layer packages that comprise high refractive index layers (refractive index ≧2.0) and low refractive index layers (refractive index <1.8), one or more of which may be applied to the substrate. The order of the high and low refractive index layers in the effect pigments may now be adapted to the pigment substrate in order to include the pigment substrate in the multi-layer pigment structure. Particularly preferred are metal oxides, metal oxide hydrates or mixtures of these, preferably Ti, Sn, Si, Al, Zr, Fe, Cr and Zn, in particular Ti, Sn and Si. The oxides and / or oxide hydrates may be present either in a single layer or in separate layers. In particular, titanium dioxide in the rutile or anatase modification, preferably the rutile modification, is used. For conversion of titanium dioxide to the rutile modification, a tin dioxide layer is preferably applied below the titanium dioxide layer. A preferred multilayer coating comprises alternating layers of high and low refractive index, preferably TiO2-SiO2-TiO2. The metal oxide, hydroxide and / or oxide hydrate layer is preferably applied by known wet-chemical methods, whereby wet-chemical coating methods developed for the preparation of effect pigments to be encapsulated on the substrate can be used. After the wet-chemical application, the coated product is subsequently separated, washed, dried and preferably calcined. The individual layer thicknesses in the effect pigments are usually from 10 to 1000 nm, preferably from 15 to 800 nm, in particular from 20 to 600 nm, in particular from 20 to 200 nm.

[0017] To improve the stability against light, temperature, water and weather, the effect pigments may be post-coated or post-treated. The post-coating may be an organic and / or inorganic coating as the final layer. The post-coating preferably comprises one or more metal oxide layers of the elements Al, Si, Zr, Ce, Fe, Cr, or mixtures or mixed phases thereof. Furthermore, organic or organic / inorganic hybrid post-coatings are possible. Silanes and / or organofunctional silanes may be used alone or in combination with metal oxides. Suitable post-coating or post-treatment methods are, for example, those described in DE 2 215 191 A1, DE 3 151 354 A1, DE 3 235 017 A1 or DE 3 334 598 A1, EP 0 090 259 A1, EP 0 634 459 A1, WO 99 / 57204 A1, WO 96 / 32446 A1, WO 99 / 57204 A1, US Pat. No. 5,759,255 A1, US Pat. No. 5,571,851 A1, WO 01 / 92425 A1, WO 2011 / 095326 A1 or other methods known to those skilled in the art. Effect pigments that can be used in the present invention are, for example, commercially available interference pigments or pearlescent pigments offered under the trade names Iriodin®, Pyrisma®, Xirallic®, Miraval®, Colorstream®, Spectraval®, RonaStar®, Biflair® and Lumina Royal®. Other commercially available effect pigments may also be used. In particular, Colorstream®, Xirallic®, Miraval® and Ronastar®, Pyrisma® pigments may be used.

[0018] An individual TFCL according to the invention may comprise a mixture of two or more, preferably three or more, different effect pigments, very preferably one or more of silver-white, yellow, red, green and blue effect pigments, whereby an even wider color space / range can be achieved depending on the concentration of the individual effect pigments, resulting in further special effects. In this preferred embodiment, the effect pigments can be mixed in any proportion, but preferably the total content of all effect pigments in one TFCL does not exceed 40% by weight, more preferably 10% by weight. However, in a preferred embodiment, each individual TFCL according to the invention contains only one colour effect pigment, preferably selected from the group consisting of silver-white, yellow, red, green and blue. The concentration of the effect pigments in the individual TFCLs according to the invention is preferably 0.01-20%, very preferably 0.02-15% by weight. More preferably, the concentration of the effect pigments in the individual TFCLs according to the invention is 0.05-10% by weight, even more preferably 0.1-5% by weight, most preferably 0.1-1% by weight. In another preferred embodiment, 1 m of individual TFCLs according to the invention 2 The amount of effect pigment per square meter is 0.1-75 g / m 2 More preferably, it is in the range of 0.2 to 30 g / m 2 , very preferably 0.5 to 15 g / m 2 , and most preferably 0.5 to 6 g / m 2 The range is.

[0019] In addition to the effect pigment, the TFCL may also contain one or more additives. For example, it may contain one or more light scattering centers or particles, which impart haze to the pigment-containing layer and advantageously reduce the appearance of dark patterns in the solar cell array structure or in the form of electrical interconnect busbars, while not significantly reducing the transmittance of the pigment-containing layer and thus not adversely affecting the power conversion efficiency of the solar cell. Suitable and preferred light scattering centers and particles are disclosed, for example, in Chinese Patent Application No. 113809194. In a preferred embodiment, the TFCL comprises one or more light scattering particles selected from silica spheres or powder, spherical silicone resin powder, BaSO4, Al2O3, BaMgAlOx or Eu-doped BaMgAlOx particles, or glass bubbles, preferably in an amount of 0.001-10%, more preferably 0.005-10%, even more preferably 0.005-5%, very preferably 0.005-3%, most preferably 0.01-1.5% by weight, and even more preferably 0.1-10 g / m 2 Contains at a concentration of The TFCL according to the invention containing effect pigments is preferably selected from polymer films or sheets. Preferred polymer films are selected from polyolefin polymers or copolymers, including but not limited to polyethylene, EVA (ethylene vinyl acetate), EBA (ethylene butyl acrylate), EMA (ethylene methyl acrylate), EEA (ethylene ethyl acrylate), POE (polyolefin elastomer), BPO (polyolefin copolymer), especially polyethylene polymers or copolymers, also PVB or TPU (thermoplastic polyurethane), preferably EVA or polyethylene copolymers. In another preferred embodiment, the front transparent cover layer is a polymer film or sheet that is integrated into a solar cell module or an architectural glass facade. The thickness of the individual TFCLs containing effect pigments is preferably in the range of 5-1000 μm, more preferably 20-800 μm, even more preferably 100-300 μm.

[0020] Optional additives such as effect pigments and light scattering particles may be incorporated into the TFCL according to the present invention by methods known to those skilled in the art and described in the literature. When the TFCL according to the invention is a polymer film, it may be made, for example, by an extrusion process, such as melt extrusion of a polymeric material, with the effect pigment and any optional additives being added to the polymer melt prior to extrusion. In extrusion, a thermoplastic is melted into a viscous mass by a screw and then forced through a flat film die into a shape. The variety of possible shapes is enormous. Films, foils, and plates are extruded through flat dies. Finally, polymer films are usually structured, e.g. embossed, on a heated and structured roll to improve ventilation during the lamination process of the photovoltaic modules. According to the invention, one or more layers of the multi-layer stack can be structured. The structuring or embossing of each individual film can improve the orientation of the effect pigments in the film, especially in very thin films, and therefore can also be used to individually select the appearance of the TFCL film stack. Usually, masterbatches or compounds are used to color the molten mass with effect pigments and optional additives. To obtain satisfactory results in plastic extrusion with effect pigments and optional additives, a balanced ratio must be maintained between the mixing energy to avoid as much damage as possible to the effect pigments and / or additives. Excessive shear in the mixing section or inappropriate screws or filters will destroy the effect pigments and dramatically reduce the pearlescent effect. Pigment orientation is important to obtain a uniform effect. This must be ensured in the process by corresponding technology and machine design.

[0021] In a preferred embodiment of the invention, a masterbatch containing the effect pigment and optional additives in the desired amount, e.g. 5-30% by weight, in the polymeric material is added during the extrusion process of the polymeric film, for example by premixing the pigmented masterbatch pellets with the EVA pellets or by other known methods. The shear forces acting on the effect pigments during the melt extrusion process cause the effect pigments to orient substantially parallel to the seal film surface. In another preferred embodiment, the TFCL containing effect pigments and scattering particles is a coextruded film of two or more layers of the same or different polymeric materials, at least one layer, preferably the layer facing the front sheet, contains one or more effect pigments. In another preferred embodiment, two or more TFCLs are heat compressed, optionally together with an additional front layer, to form a fused multi-laminate. Used as an encapsulant for lamination of PV modules, EVA is a thermoplastic polymer in a formulation that is particularly suited for use in solar power generation applications. EVA offers high electrical insulation, transparency, flexibility, and softness. In crosslinked formulations (like encapsulants), it also exhibits high dimensional stability, fast cure, and easy lamination. A typical EVA formulation usually contains crosslinkers, adhesion promoters, UV absorbers, UV stabilizers, and antioxidants in addition to the polymer resin. The crosslinkers are radical initiators, usually peroxides, that decompose in the heat of lamination to form free radicals, initiating radicals on the polymer backbone. The radicals formed form covalent bonds between the polymer chains.

[0022] The TFCL according to the invention containing effect pigments may be a glass, enamel or ceramic layer.Therefore, in another preferred embodiment, at least one, preferably only one, of the TFCLs is a glass, enamel or ceramic layer, and the other TFCLs are selected from polymer films or sheets.For example, according to this preferred embodiment, it is possible to provide a first TFCL, which is a glass, enamel or ceramic layer containing a first effect pigment, for example silver-white or another color, on which a second TFCL containing a second effect pigment and optionally further TFCLs each containing an effect pigment are laminated, these second and further TFCLs being polymer films, and the second and further effect pigments are selected from, for example, yellow, red, green and blue effect pigments. However, it is generally more preferred to use a polymer film as the TFCL to take full advantage of the aforementioned advantages associated with flexibility and reproducibility in providing customized colors on a large scale. When the TFCL containing effect pigments is a glass, enamel or ceramic layer, its thickness is preferably 5-200 μm, very preferably 10-100 μm, most preferably 15-70 μm.

[0023] The glass layer, TFCL, may be prepared, for example, by mixing the effect pigment and any additives with a glass frit or flux, ceramic, or enamel precursor, placing the mixture on a substrate, and firing or heating the mixture above the glass temperature of the glass frit, flux, ceramic, or enamel, respectively. Typical methods of applying the precursor composition to a substrate include roller coating, screen printing, or spraying a mixture of the flux, enamel, or ceramic precursor, pigment, and optionally other additives, in a solvent such as water or glycol ether. In particular for the decoration of glass products, especially glass sheets, a precursor composition is preferably used that contains one or more pigments, optionally one or more additives, and one or more glass frits or fluxes. The precursor composition is coated on a substrate and then fired, thereby forming a glass enamel containing the pigments and optional additives. In the application of the precursor composition to the glass sheet, the melting behavior of the precursor composition shall be adjusted according to the typical conditions of the tempering process. Typical firing conditions are a glass temperature of about 580-650°C and a firing time of several minutes. For colorful decoration of glass sheets in the glass area for architecture and equipment, a good compatibility between the glass frit and the inorganic pigments contained in the composition is required. The requirements of the fired composition, i.e. glass enamel, in many areas of use include smooth firing in a short time and at the lowest possible temperature, avoidance of cracks, good chemical resistance to acid and alkaline substances, and good weather resistance. A preferred flux is a cadmium- and lead-free flux based on, for example, borosilicate glass, with Si, Zn, and B as the main components. The TFCL according to the present invention can also provide color tones or color patterns such as to mimic a brick wall, which can be achieved for example by screen printing two different colors in a desired pattern, or it can also provide various surface tones of materials used in the construction of a house, which can be achieved for example by spraying two different tones onto each other.

[0024] The effect of pigments and layers on c-Si solar cells can be evaluated by reflectance data. Reflectance data is used to estimate the maximum power absorption / maximum photocurrent generation of the processed cells. Reflectance and transmission measurements and calculations are performed by general methods known to those skilled in the art and further described in the experimental section. The transmittance of the individual TFCLs containing effect pigments is preferably ≧50%, more preferably ≧70%, very preferably ≧80% for light in the range 500-800 nm, more preferably in the range 400-1000 nm, most preferably in the range 300-1150 nm. The reflectance of the individual TFCLs containing effect pigments is preferably ≦50%, more preferably ≦30%, very preferably 1-20% for light having a wavelength in the range 500-800 nm, more preferably 400-1000 nm, most preferably 300-1150 nm. Even with reflectances as low as 1-5% the color is already visible. A preferred colored solar cell or colored solar cell module comprises the following elements: - two or more TFCLs containing effect pigments as mentioned above and below - optionally one or more further transparent layers on the front side of the solar cell - one or more solar cells, or an array of solar cells electrically interconnected by conductive parts, preferably bus bars; - Optionally, a rear sealing sheet - Rear seat

[0025] A colored solar cell module according to the present invention is exemplarily and diagrammatically shown in Figure 1 and comprises a front sheet (11), three TFCLs (12a,b,c) each containing a different effect pigment, which may also function as a front encapsulant sheet, a pattern or array of solar cells with busbars (13), an optional rear encapsulant sheet (14), and a rear sheet (15). The arrows indicate the direction of incident light. The number of pigmented TFCLs (12a,b,c) can also be varied, for example, to 2, 4, 5, or 6 individual layers. The TFCLs can also be laminated and pressed under heat, optionally together with a transparent front sheet (11), to form a monolithic multilayer. In another preferred embodiment (not shown in Figure 1), one or more front sealing films (16) are provided between the front sheet (11) and the pigment-containing layers (12a, b, c) or between the pigment-containing layers (12a, b, c) and the solar cells (13). The front sealing film (16) does not contain effect pigments. In another preferred embodiment (not shown in FIG. 1), the solar module does not include a front sheet (11), and the effect pigment-containing TFCL (12a, b, c) functions as the front sheet. In another preferred embodiment (not shown in FIG. 1), one or more of the TFCLs (12a, b, c), preferably the outermost TFCL (12a), functions as the front encapsulation sheet. In another preferred embodiment (not shown in FIG. 1), a protective or cladding foil is applied over the completed solar cell or solar module. The TFCLs (12a, b, c) are arranged on the radiation receiving side, i.e. in the visible part of the solar cell or solar cell module according to the invention. They may be arranged on the inside of the front sheet (11) in the solar cell module, i.e. on the side facing the solar cell or array of solar cells, as shown in Figure 1, or alternatively on the outside of the front sheet (11), i.e. on the side facing the incident light. TFCL (12a, b, c) can be applied topically and flexibly to any surface, i.e. directly onto the exterior of a finished solar cell or solar module, onto a protective substrate (glass or plastic) covering the solar cell or solar module, or onto the photoactive material / solar cell. Advantageously, the TFCLs (12a,b,c) can also be used as anti-reflective films. Generally, the components located on the front side of the solar module, such as the front sheet (11), TFCL (12a, b, c), and any additional front encapsulant films, are substantially transparent to incident light passing through the solar cells or solar cell array (13).

[0026] If the layer or sheets (11, 12a, b, c, 14, 15, 16) on the front and rear side are polymer films, they are preferably made of e.g. polyethylene, EVA (ethylene vinyl acetate), EBA (ethylene butyl acrylate), EMA (ethylene methyl acrylate), EEA (ethylene ethyl acrylate), POE (polyolefin elastomer), BPO, further polyester, polyamide, polyurethane, polyvinyl butyral PVB, polycarbonate, polyvinyl chloride, polyvinyl acetate, polyacrylate, polyol, polyisocyanate. , or polyamines, as well as organic polymers including, but not limited to, polycarbonate-containing urethane resins, vinyl chloride-vinyl acetate-containing urethane resins, acrylic resins, polyurethane acrylic resins, polyester resins, or copolymers, resins, blends, or multilayers of the above, such as TPU (thermoplastic polyurethane), very preferably TPU, or polyolefins including, but not limited to EVA, EBA, EMA, EEA, POE, or BPO, most preferably EVA. The TFCL (12a, b, c), the optional front sealing sheet (16), and the optional rear sealing sheet (14) are preferably selected from polyolefin polymer or copolymer films, very preferably from polyethylene polymer or copolymer films, especially from EVA, EBA, EMA, EEA, POE, BPO, PVB, or TPU films, and most preferably from polyethylene copolymer or EVA films.

[0027] The front sheet (11) and the rear sheet (15) are preferably selected from glass sheets. In another preferred embodiment, the front sheet (11) and / or the rear sheet (14), more preferably the rear sheet (15), are polymer sheets, such as TPT or polycarbonate sheets. Further preferred polymers for use as or in the backsheet (15) can be classified as double fluoropolymers, single fluoropolymers, and non-fluoropolymers, as well as various structures within each category. Double fluoropolymer backsheets typically consist of an exterior layer of primarily Tedlar® polyvinyl fluoride (PVF) film, or Kynar® polyvinylidene fluoride (PVDF) film, and a core layer of polyethylene terephthalate (PET). Single fluoropolymer backsheets typically consist of Tedlar or Kynar® on the air side, and PET and a primer or EVA layer on the inside. Non-fluoropolymer backsheets typically consist of two PET and one primer or EVA layer. In a preferred embodiment of the present invention, the rear sheet (15) is dark in color, such as black or dark blue, and / or a black or dark colored sheet, e.g., a rear sealing sheet (14), is provided on the rear side of the solar cell or solar cell module, i.e., between the solar cells (13) and the rear sheet (15), the dark color being preferably dark blue equal to the color of the solar cells.

[0028] The solar cell array (13) illustratively shown in FIG. 1 may be replaced with a single solar cell. The colored solar cell or colored solar cell module according to the invention, and the solar cell (13) of Fig. 1, can be selected from any type of device for collecting and converting solar energy, such as a solar thermal device or a photovoltaic device, including but not limited to organic photodiodes, solar cells or solar cell modules, which can be of organic, inorganic or hybrid type, including but not limited to amorphous, monocrystalline and polycrystalline silicon solar cells, CIGS, CdTe, III / V solar cells, II / VI solar cells, perovskite solar cells, organic solar cells, quantum dot solar cells and dye-sensitized solar cells, as well as solar cell modules consisting of single cells. Crystalline solar cells include cell structures such as Al-BSF, PERC, PERL, PERT, HIT, IBC, bifacial, or any other cell structure based on a crystalline silicon substrate. The colored solar cell or colored solar cell module according to the invention and the solar cell (13) in FIG. 1 may also be selected from devices for collecting and converting solar energy, such as solar thermal devices or photodiodes. In the solar cell (13), the conductive parts preferably include metal-based conductive parts, including but not limited to the following components: i) The H-grid, which consists of the main vertical connectors, the so-called busbars ii) Horizontal current collecting elements, known as fingers iii) Inter-cell connectors and solder In a preferred embodiment of the present invention, in order to achieve a completely homogenous appearance of the solar cell (13), the metal-based conductive parts, including but not limited to the aforementioned components i) to iii), are preferably pigmented in a dark color, such as black or deep solar blue, before application of the layer with effect pigments and light-scattering centers (12).

[0029] In another preferred embodiment of the invention, a dark, preferably black or dark blue, grid is incorporated into one or more layers of the solar cell, said grid covering light areas such as the spaces between the single solar cells and the conductive parts including bus bars, conductive tracks and soldering points. In another preferred embodiment of the invention, a black or dark blue back layer is applied to the back of the solar cell to hide the spaces between the single solar cells. The black or dark blue back layer can be applied by printing or as a foil. Suitable and preferred methods for darkening the otherwise white-looking metal parts of solar cells (13) with an H-grid front pattern include covering the metal stripes with a black polymer foil or painting the metal parts with black paint. In the case of a printed silver H-grid, the silver can be directly blackened by forming a thin layer of silver sulfide (e.g., treatment with H2S) or by plating and oxidizing the copper. In the case of plated metal grids, the top layer of the metal stack can be directly plated with a highly absorbing metal oxide or sulfide such as CuO or Ag2S, or a similar dark metal oxide. When using novel metallization techniques (such as smart wire technology), blackened wires or wires with microstructures that darken the appearance of the metal grid by reducing the reflectivity can also be used according to the present invention. Using a black or deep solar blue rear sheet as the background of the module allows a very homogenous appearance across the module, even from close distances.

[0030] The colored solar cells and colored solar cell modules according to the invention can be produced by methods and means known to those skilled in the art and described in the literature. For example, existing state-of-the-art manufacturing techniques for encapsulated solar modules often involve forming a stack of front glass and solar cells that are attached to bus bars, wrapped in an encapsulating film, and laminated to a back sheet or glass. The stack is then heated, for example to 130-160°C (depending on the type of encapsulant used), and pressed with a vacuum or other type of physical pressure. Preferably, the TFCL with effect pigments and the other individual components or layers of the solar cell module described above and below are stacked in a desired order and then laminated together, for example by applying heat and / or pressure or using an adhesive or binder. Alternatively, the lamination process for producing the solar cell module(s) can be carried out in two steps, with the effect pigment-containing layer being laminated to the front sheet in a first lamination (or pre-lamination) step, and then the laminate of front sheet and effect pigment-containing layer is laminated to the remaining component stack in a second lamination step. A preferred process for making a coloured solar cell or solar cell module according to the invention comprises stacking two or more TFCLs containing the effect pigments described above and below onto the front side of a solar cell or solar cell module, where at least two of the effect pigments of the TFCLs have different colours. The lamination step can be carried out using standard methods, for example by applying heat and pressure to the two layers, for example by applying a vacuum and / or any other form of physical pressure, for a period of time, for example in a lamination machine.

[0031] Alternatively and / or additionally, lamination can be achieved or supported by the use of one or more adhesives and / or binders or layers. The adhesives / binders may be reactive or non-reactive and may comprise or consist of natural or synthetic origin. Suitable and preferred examples include, but are not limited to, polyurethane (PUR), thermoplastic polyurethane (TPU), rubber, acrylic, and silicone adhesives, depending on the desired application. In the lamination step, the suitable heat and pressure applied and time interval will vary depending on the type of sheets and films used and can be easily selected by one skilled in the art. When using a front glass sheet and a polymer film of EVA, the heating temperature is preferably in the range of 130-160°C, very preferably about 135°C, and the time interval is preferably 20-30 minutes. A vacuum press is preferably used. A pressure of 400-900 mbar is preferably applied. After the final lamination step, the laminated stack is cooled, preferably to room temperature. The excess of the sealing film and backsheet (if a plastic backsheet is used) can be trimmed off, and a junction box can be attached for the electrical connections of the solar cell module. Finally, the laminate can be placed into a frame. After the lamination step, the film thickness typically decreases depending on the lamination conditions. Preferably, the resulting laminate is completely hermetic and ideally can protect the solar cell for at least 25 years.

[0032] Preferably, the solar cells and solar modules according to the invention exhibit a power output change ΔP of >−20%, more preferably >−10%, very preferably >−6%,

number

[0033] [Example 1] Stack of colored polymer films Contains 0.15% effect pigment, resulting in an effect pigment concentration of approximately 1 g / m 2 Various polyethylene films according to the present invention were prepared, Sealing films are usually produced by extrusion of cast films, but in this example, for practical reasons, film samples measuring 10 × 15 cm and 700 μm thick were produced by injection molding of polyethylene resin containing pigments and particles as follows. A Kraus-Maffei CX-130-380 type injection molding machine was used. After the mold was closed, a transparent plastic melt (Evatane® 28-25PV, manufactured by Arkema) was injected into the injection mold. The injection operation was carried out at temperatures ranging from 180 to 200 °C, pressures of 450 to 900 bar (4.5 × 10 7 ~9×10 7 N / m 2) pressure range. For the addition of coloring or scattering particles to the plastic melt, masterbatches were used at the required concentration accordingly. The polymer film can be embossed in a later step if required. The embossed structure usually helps to remove air during the lamination step of the solar module. On a 6 x 12 cm glass sheet, a black EVA film with a size of 10 x 6 cm is placed, leaving part of the glass uncovered. On top of the black EVA film, an EVA film containing a red effect pigment (Pyrisma® T30-21 Color Space Red), an EVA film containing a green effect pigment (Pyrisma® T30-24 Color Space Green), and an EVA film containing a blue effect pigment (Pyrisma® T30-23 Color Space Blue) are placed, each film having a thickness of 450 μm (450 g / m 2 ) and 6x12 cm in size. The red, green and blue effect pigments are interference pigments consisting of a natural mica substrate with a TiO2 coating. On top of this a second glass sheet of 6x12 cm is placed. The stack is then placed in a vacuum bag and placed in an oven. The stack is treated at 150°C for 10 minutes at 70 kPa. After cooling the sample is removed from the vacuum bag. A grey multilayer film is obtained. A transmittance measurement is carried out on the areas where no black EVA has been placed. When comparing the transmittance with the unpigmented standard laminate stack, the effect pigments only reduce the transmittance by less than 20%.

[0034] [Example 1] Stack of colored polymer films and colored glass Film preparation Contains 0.15% effect pigment Pyrisma® T30-24 Color Space Green, resulting in an effect pigment concentration of approximately 1 g / m 2 An EVA film having a thickness of 450 μm was prepared. Preparation of tinted glass front sheet A layer containing the effect pigment Pyrisma® T30-23 Color Space Blue in an aqueous glass / frit mixture is printed directly onto commercial glass used for photovoltaic modules by modern screen printing to give a wet layer of 35-40 μm. The printed glass is then heat strengthened in an oven at 600-680 °C to give a thickness of 20-25 μm and a coating weight of 1 g / m of effect pigment. 2 A dry layer of glass enamel is formed. Sample preparation A sample is prepared having the following layers: - 10cm x 10cm, 2mm thick non-tinted glass - 10cm x 5cm black EVA film - 1g / m 2 A 10cm x 10cm colored encapsulating EVA film (450μm) colored with Pyrisma® T30-24 Color Space Green from - 1g / m 2 10cm x 10cm, 2mm thick tinted glass stained with Pyrisma® T30-23 Color Space Blue from - Vacuum-bagged stack of layers treated in a drying cabinet at -70 kPa and 150 °C for 10 min. After cooling, the sample is removed from the vacuum bag. A turquoise multilayer film is obtained. A transmittance measurement is performed in an area where no black EVA is placed. When comparing the transmittance with a non-pigmented standard laminate stack, the effect pigments only reduce the transmittance by less than 20%.

Claims

1. A colored solar cell or colored solar cell module comprising two or more transparent front cover layers, wherein each of the transparent front cover layers contains at least one effect pigment having a specific color and consisting of a transparent or translucent flake-shaped substrate coated with one or more layers of transparent or translucent material and optionally a post-coating, and at least one of the transparent front cover layers contains an effect pigment having a different color from the effect pigment contained in the other transparent front cover layers.

2. The colored solar cell or colored solar cell module according to claim 1, wherein the transparent front cover layer is selected from a polymer film or a sheet.

3. The colored solar cell or colored solar cell module according to claim 1, wherein the transparent front cover layer is selected from EVA, EBA, EMA, EEA, POE, PC, BPO, PVB, or TPU film.

4. The colored solar cell or colored solar cell module according to claim 1, wherein the transparent front cover layer is a sealing film or a component thereof, or together forms a sealing film or a component thereof.

5. A colored solar cell or colored solar cell module according to claim 1, comprising two or more, preferably two, three, four, or five transparent cover layers, at least one of which preferably contains an effect pigment having a different color from the effect pigments contained in the other transparent front cover layers.

6. A colored solar cell or colored solar cell module according to claim 1, comprising two or more, preferably two, three, four, or five transparent front cover layers, at least one of which preferably contains an effect pigment selected from silver-white, yellow, red, green, and blue effect pigments, having a different color from the effect pigments contained in the other transparent front cover layers.

7. The colored solar cell or colored solar cell module according to claim 1, characterized in that the concentration of the effect pigment in each transparent front cover layer is 0.02 to 15% by mass.

8. The colored solar cell or colored solar cell module according to claim 1, wherein the transmittance of each transparent front cover layer is ≥50%, preferably ≥70%, and most preferably ≥80% for light having a wavelength of 500 to 800 nm.

9. The colored solar cell or colored solar cell module according to claim 1, wherein the thickness of each transparent front cover layer containing the effect pigment is in the range of 5 to 1000 μm, preferably 20 to 800 μm, and very preferably 100 to 300 μm.

10. The colored solar cell or colored solar cell module according to claim 1, characterized in that the effect pigment is selected from pearlescent pigments, interference pigments, and multilayer pigments.

11. The aforementioned effect pigment is synthetic or natural mica, flake-shaped glass substrate, flake-shaped SiO 2 Base material, or flake-shaped Al 2 O 3 A colored solar cell or colored solar cell module according to claim 1, characterized in that it is based on a substrate.

12. The colored solar cell or colored solar cell module according to claim 11, characterized in that the flake-like substrate is coated with one or more layers of metal oxides and / or metal oxide hydrates of Ti, Sn, Si, Al, Zr, Fe, Cr, or Zn.

13. The following elements - Two or more transparent front cover layers as defined in claim 1 - Optionally, one or more additional transparent layers on the front side of the solar cell. - One or more solar cells, or an array of solar cells electrically interconnected by conductive parts, preferably busbars. - Optionally, rear sealing sheet - Rear seats Colored solar cells or colored solar cell modules containing colored solar cells.

14. The colored solar cell or colored solar cell module according to claim 13, characterized in that the rear sheet is black or dark in color, and / or the colored solar cell or colored solar cell module includes an additional sheet or sealing film provided between the solar cell or solar cell array and the rear sheet, wherein the additional sheet or sealing film is black or dark in color.

15. A method for producing a colored solar cell or colored solar cell module according to any one of claims 1 to 14, comprising the step of laminating two or more transparent front cover layers as defined in one or more of claims 1 to 12 on the front side of the solar cell or solar cell module, wherein at least one of the transparent front cover layers contains an effect pigment having a different color from the effect pigment contained in the other transparent front cover layers.

16. The method according to claim 15, characterized in that the lamination step is preferably carried out by vacuum pressing by applying heat and / or pressure, or by using an adhesive, binder, or layer.

17. Building fixtures or devices comprising one or more colored solar cells or colored solar cell modules as described in any one of claims 1 to 14, selected from the group consisting of windows, doors, building facades, building roofs or floors, walls, structural glass, curtain walls, showrooms, car roofs, car bodies, mobile phones, portable PCs such as tablets, plug-in solar cell modules, roof tiles, solar panels, PV fences, military equipment, radio equipment, radio equipment, music boxes, power banks, clocks, eyeglasses, and goggles.

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