WO2011160786A2 - Method for producing a thin-layer solar module, and thin-layer solar module - Google Patents

Abstract

The invention relates to a method for producing a thin-layer solar module, having the following steps: supplying a first light-permeable substrate with an active region for converting solar energy, supplying a second substrate, retaining the first and second substrates parallel to one another and at a predetermined distance from one another, wherein the active region is arranged between the first and second substrates, filling the interspace with a liquid material, and hardening the liquid material in order to encapsulate the active region. The invention further relates to a method which is intended for producing a thin-layer solar module and has the following steps: supplying a first light-permeable substrate with an active region for converting solar energy, applying a liquid material to the side of the light-permeable substrate with the active region, and hardening the liquid material to encapsulate the active region. The invention also relates to solar modules produced in a corresponding manner.

Description

 Method for producing a thin-film solar module and

 Thin Film Solar Module

The invention relates to a method for producing a thin-film solar module and to thin-film solar modules produced in this way.

Such modules are known. A thin film solar module comprises a first translucent substrate, typically of glass. This element is also referred to as a front glass, as it faces the sun and light is incident on this element in the photovoltaic module. On the translucent substrate is a transparent conductive layer. This is followed by at least one photovoltaically active layer. In this layer, the incident light is converted into electricity. On the other side of the active layer is a second conductive layer, in particular a second transparent layer, which is for example made of the same material as the first transparent conductive layer. These layers form the so-called active area. Via a plastic film, for example of PVB or EVA, the structure with a second substrate, preferably made of glass (also called back glass) or TEDLA film, whereby the active area is encapsulated to protect it from negative environmental influences.

These modules are produced in a lamination process using a vacuum laminator or autoclave. This is time consuming and can only be done in batch mode.

It is therefore an object of the invention to simplify the production process in order to be able to provide a continuous process.

This object is achieved with the method for producing a thin-film solar module according to claim 1. According to the invention, the method comprises the steps of: a) providing a first translucent substrate having an active region for converting solar energy, b) providing a second substrate, c) holding the first and second substrates parallel to each other with a predetermined spacing to each other with the active region disposed between the first and second substrates, d) filling the gap with a liquid material, and e) curing the liquid material thereby encapsulating the active region. With this method, one can dispense with the use of the autoclave and the process can be carried out in a continuous process. This simplifies the manufacturing process.

The object is further achieved with the method for producing a thin-film solar module according to claim 2. This comprises the steps of: f) providing a first translucent substrate having an active region for converting solar energy, g) applying a liquid material to the side of the translucent substrate with the active region, and h) curing the liquid material thereby encapsulating the active region becomes. Also according to this method, one can dispense with the use of an autoclave and perform the process in a continuous process. In addition, it is still possible to dispense with the use of the second substrate, which is usually made of glass and therefore quite heavy in this process. The modules become lighter and the construction easier.

Preferably, prior to step h), one or more fasteners may be provided for attaching the thin film solar module to a substructure and / or one or more electrical connection devices and / or one or more reinforcing elements over the side of the translucent substrate having the active region and after step h) the hardened material integrated, in particular positively connected, be. Thus, in one process step, the further elements required for the use of a module can be integrated. Additional glue steps are therefore no longer necessary. The connection devices can be designed so that means for strain relief of the connection cable of the active area can be poured simultaneously with the encapsulation.

Preferably, in step g), a mold can be provided in which the liquid material is filled. With the help of the mold thus any geometric structures for the encapsulation can be achieved.

According to a further preferred embodiment of the invention, the steps g) and h) are performed several times to form a plurality of layers. Preferred may for the several layers different shapes are used. So you can selectively arrange more material at predetermined locations.

Advantageously, after step h), the hardened material may have different thicknesses, in particular in the form of reinforcing ribs. When using reinforcement areas, the necessary stability can be ensured by the encapsulation material and thus the use of steel, aluminum or stainless steel elements, as is still common in the known modules, can be considerably reduced. Thanks to the areas with different thicknesses, the module can be load-optimized, voltages can be compensated and / or voltage peaks can be recorded.

Preferably, the one or more fasteners and / or the one or more attachment devices and / or the one or more reinforcement elements may be arranged to be in thicker regions of the cured material after step h). As a result, the use of materials is further improved.

Advantageously, the reinforcing ribs may be at least partially arcuate. In such geometries can be made possible with optimization of the material use nevertheless a uniform load on the module, since the thicker areas can extend along areas of higher voltages.

According to a preferred embodiment, the liquid material can be provided so that after step h) the cured material protrudes laterally at least in sections over the edge of the substrate and / or surrounds the edge of the substrate. This also provides a protection area in a process step in order to prevent damage to the light-transmitting substrate.

Further advantageously, the cured material may have reflective properties, in particular a white color, and / or protective or stabilizing properties. This eliminates the need for additional reflective layers and the structure of the module can be further simplified. With protective or stabilizing properties, the service life can be extended

Preferably, the liquid material may be a polymer material, in particular a polyurethane plastic. Polymer materials are lightweight and can be used in any Molds are poured. Thus, lighter modules can be provided, which nevertheless ensure the requirements for a long-lasting encapsulation.

Further preferably, fillers, in particular fiber reinforcements and / or fillers for influencing thermal and / or electrical properties, may be added in step d) or g). As a result, the structure of the module can be further optimized and optionally adapted to different purposes.

Particularly preferably, the additions can be designed so that inhomogeneous distributions result in the cured material. The inhomogeneous distributions can be formed laterally as well as in the direction of the layer thickness. For example, the layers provided by repeating steps g) and h) may have different properties from each other to achieve such inhomogeneous distributions. For example, one layer can be made electrically conductive, while another layer is particularly reinforced. Overall, the properties of the module can be further improved by the inhomogeneous addition.

The object of the invention is also achieved by the solar module according to claim 14. This module may in particular be a thin-film solar module and comprises a first transparent substrate having an active region for converting solar energy, a second substrate and a layer connecting the transparent substrate and the second substrate, wherein the active region is arranged between the first and second substrates characterized in that the connecting layer is made of a cured polymer material. This provides a solar module that is easier to manufacture than conventional plastic-film modules.

The object of the invention is likewise achieved with a solar module according to claim 15. This may in particular relate to a thin-film solar module and comprises a first transparent substrate having an active region for converting solar energy, characterized in that the active region is covered by an encapsulation unit made of a cured polymer material, which also forms the back construction of the solar module. As a result, a lighter module can be provided compared to the known glass-glass thin-film solar modules. The polymer material may preferably have filling materials for influencing thermal and / or electrical properties. As a result, the structure of the module can be further optimized and optionally adapted to different purposes.

Advantageously, the encapsulation unit can have a plurality of layers, in particular with different thermal and / or electrical properties. The encapsulation unit can thus fulfill a number of tasks in addition to the encapsulation: provision of electrically conductive regions, for example to simplify the arrangement of the interfaces, rigidity of the module, etc.

Preferably, the encapsulation unit projects laterally beyond the edge of the substrate at least in sections and / or surrounds the edge of the substrate. This allows the substrate to be protected against breakage. In particular, the assembly is facilitated.

Advantageously, the encapsulation unit can have different thicknesses. Thus, for example, in thicker areas, further elements of a module can be inserted, or else the structure of the module can be stiffened.

In this case, one or more fastening elements for attaching the thin-film solar module to a substructure and / or one or more electrical connection devices and / or one or more reinforcement elements can be integrated into the encapsulation unit over the side of the light-transmissive substrate with the active region. Particularly advantageous is a positive connection. This eliminates the need for expensive attachment steps such as gluing or screwing.

Hereinafter, with reference to the following figures, embodiments of the present invention will be described and explained in detail. Show it

FIGS. 1a-1c show a first embodiment of the invention,

FIGS. 2a-2d show a second embodiment of the invention,

FIG. 3 shows a variant of the solar module which results from the method according to the second embodiment, FIG. 4 shows a second variant of a solar module which results from the method according to the second embodiment,

Figure 5 is a schematic cross-sectional view taken along section line A-A of

 FIG. 4,

FIG. 6 shows a third variant of a solar module which results from the method according to the second embodiment,

Figure 7 schematically shows a cross-sectional view according to a fourth variant and

FIG. 8 schematically shows a cross-sectional view according to a fifth variant.

FIGS. 1a to 1c schematically show a first embodiment of the invention. The solar modules are shown in cross section.

According to steps a), b) and c) of claim 1, a first transparent substrate 1 with an active region 3 for converting solar energy into electrical energy and a second substrate 5 are provided in FIG. The second substrate 5 is spaced from the active region 3 but arranged substantially parallel. The distance can be ensured for example via spacers, not shown here, which are arranged in the intermediate space. Alternatively, the two structures can also be arranged in each case on a holding device, which ensure the distance.

In this embodiment, the first transmissive substrate 1 and the second substrate are made of glass. This element is also referred to as a front glass, as it faces the sun and light is incident on this element in the photovoltaic module.

The active region 3 is formed by a sequence of different layers. On the translucent substrate 1 is usually a transparent conductive layer. This is followed by an active layer, for example a Si layer or a CdTe layer or a CiGSSe layer or else a tandem cell comprising a microcrystalline and an amorphous Si layer. In this layer, the incident light is converted into electricity. On the other side of the active layer becomes a second conductive layer, in particular a second transparent layer, but usually not necessarily of the same material as the first transparent conductive layer is provided. For example, SnO 2, ZnO or a metallic back contact can also be used here.

Optionally, a reflector layer may be provided on the free surface 7 of the active layer and / or the surface 9 of the second substrate. This may be a metal layer, a white film or a white-colored layer, in order to re-supply light not yet absorbed in the active layer.

According to step d) is then, as schematically indicated in Figure 1 b, the gap filled with a liquid material 1 1. For this example, a frame can be placed around the assembly 13 to prevent leakage of the material. The liquid material is a polymer material, in particular a polyurethane plastic.

According to step e) of claim 1, the liquid material is then cured whereby the active region 3 is encapsulated, that is isolated from the environment. This is shown schematically in FIG. 1 c), the hardened layer bearing the reference numeral 15. To harden the material, an oven, preferably a continuous furnace, is used.

With this method can be dispensed with the use of a plastic film and thus on the more complex lamination process using an autoclave.

Particularly preferably, the liquid material is chosen so that it has reflective properties, whereby an additional reflector layer is avoidable. This is achieved for example by a suitable color choice. Optionally, fillers may also be added to the liquid material to provide protective or stabilizing properties. This can for example affect the strength, the thermal expansion or the electrical properties.

FIGS. 2a to 2d schematically show a second method according to the invention.

According to step f) of the second claim, a first translucent substrate 1 having an active region 3 for converting solar energy into electrical energy provided. This is illustrated in FIG. 2a. The substrate 1 and the active region 3 are constructed in the same way as already described in connection with FIG. 1a. This description is hereby incorporated by reference.

FIG. 2b shows a mold 21, which is slipped over the free surface 7 of the active region 3. The mold 21 comprises one or more inlet nozzles 23 via which a liquid material can be filled into the free space 25 formed between the mold 21 and the surface in accordance with feature g) of claim 2.

After filling the liquid material 1 1, which has the same properties as already explained in connection with the first embodiment, in the free space 25 (see Figure 2c), the material is again cured in an oven by thermal treatment whereby the active region 3 encapsulated becomes. Thereafter, the mold 21 can be removed, as shown in FIG. 2d, and a thin-film solar module 27, which is composed of the first substrate 1, the active region 3 and an encapsulation unit 29, is obtained.

In addition to the advantages of the first embodiment, according to the second embodiment, it is possible to manufacture a solar module that is lighter in weight than the conventional glass glass products by using a plastic encapsulation unit 29.

The use of the mold 21 also gives the possibility of the encapsulation unit 29 to give any desired shapes. Thus, the thickness of the layer 29 need not be constant over the module surface. As a result, it is possible, for example, to achieve reinforcing elements, such as ribbed structures, in one process step.

By repeating the steps shown in FIGS. 2 b and 2 c, it is also possible to provide a multi-layer encapsulation unit 29, wherein the individual layers may have different properties with regard to strength, electrical conductivity, coefficient of expansion, etc. This can be achieved, for example, by adding filler materials, such as electrically conductive particles or reinforcing fibers, into the liquid material 11. In particular, different forms 21 are used. In a further embodiment of the second embodiment, it is also possible to use a mold 21 which protrudes laterally beyond the edges 31 of the active region 3 and possibly also beyond the edges 33 of the substrate 1 (see FIG. 2b). During curing, an edge then protrudes laterally in the layer 29 'and possibly even covers the edges 33 of the substrate 1 and thus serves as edge protection. This is shown schematically in FIG. In one variant, the cured material can also be partially present beyond the edge 33 on an edge region 34 on the surface of the substrate 1 in order to further optimize the edge protection.

FIG. 4 illustrates a second variant of a solar module which results from the method according to the second embodiment. Shown is a solar module 41 with substrate 1 and active area 3, these will not be described in detail. It is merely referred to the description above. The encapsulation unit 29 "in this embodiment comprises arcuate reinforcing ribs 43 and 45, which serve to optimize the load on the module 41, to compensate for stresses and / or to absorb voltage peaks, in order to be able to produce these, it is sufficient to use a mold 21 with a corresponding structure. In this case, the structure can be produced in one or more steps by using a single mold or several molds 29. For example, if the ribs 43 and 45 have different material properties compared to the base 47, two molds 21 will be used.

Naturally, more or less ribs can also be used according to the invention. These can also be straight.

In addition, in this embodiment, the electrical terminal portions 51 and 53 of the module are integrated with the reinforcing ribs 43 and 45. The connection regions 51 and 53 can represent their own components, which were inserted into the still liquid material 11 and then connected to the encapsulation unit during curing of the material, or be produced directly by appropriate shaping of the encapsulation unit. In this case, for example, even a strain relief for the coming out of the active area 3 connecting strips are provided. The arrangement of the connection areas in the ribs is to be seen here only as a variant. Of course, the connection areas could also be arranged outside the ribs 43 and 45.

Figure 4 also shows four fasteners 55, 57, 59, 61 with which the module 41 can be attached to a substructure. According to the invention, these can be integrally formed with the encapsulation unit 29 "or represent their own elements, for example made of steel or stainless steel, which are held in the preparation in the liquid material 1 1 and after curing then integrated into the encapsulation unit 29", for example via a positive connection, are.

FIG. 5 shows this in a cross-sectional view along section line A-A. Once again, the substrate 1 and the active region 3 can be seen there, and the encapsulation unit 29 "with the two ribs 43 and 45. Profiles 63 and 65 are embedded in the encapsulation unit at the level of the fastening elements 55 and 59. These are part of the fastening elements 55 and 59. Due to the open structure, the liquid material 11 has entered the open profile and, after curing, the fastener 55 and 59 is thus retained in the encapsulation unit 29 ". In one embodiment, the profiles 63 and 65 may each extend from one fastening element 55 or 59 to the opposite fastening element 57 or 61.

FIG. 6 shows a third variant of a solar module 71 resulting from the method according to the second embodiment. Shown is a solar module 71 with substrate 1 and active area 3, these will not be described in detail. It is merely referred to the description above. The encapsulation unit 29 '"comprises a plurality of layers 73, 75, 77 with different geometries Each layer 73 to 77 was produced with its own shape 21 see Figure 2b The material properties of the individual layers, in particular the thermal and / or electrical properties, can be determined by a For example, it is possible to optimize the mechanical, electrical and / or optical properties of the encapsulation unit 29 "'by means of the addition of filling materials. The illustrated geometries are shown here by way of example only. Other geometries are also conceivable and according to the invention. The embodiment illustrated in FIG. 6 may also be provided by integrated electrical connection devices and / or fasteners are completed according to the manner shown in Figure 4.

FIG. 7 shows a fourth variant with substrate 1 and active region 3. The encapsulation unit 29 ^IV . In this encapsulation unit reinforcing struts 81, 83, 85, 87 are embedded, which may preferably extend over the entire width of the module 89. In this variant, the reinforcing struts 81 and 87 are simultaneously provided as fastening elements and formed correspondingly thicker. Typically, these struts are made of steel, aluminum or stainless steel. The thickness of the cured material is adapted to the different heights of the reinforcing struts, so that forms a wavy, smooth surface.

FIG. 8 shows a fifth variant. In contrast to the fourth variant has the areas between the reinforcing braces 91, 93, 95 of the capping unit are formed thicker ^v 29 in order to ensure the desired bending rigidity of the module 97 here.

The individual features of the different embodiments can be combined with each other as desired. With respect to the first and second embodiments and the various variants of the resulting modules, the invention is not limited only to thin-film solar modules. Rather, it is also applicable to crystalline modules.

With the modules according to the invention, on the one hand, the production process is simplified and, on the other hand, a weight reduction can be achieved when using the encapsulation unit. Thanks to the integrated reinforcement elements as well as the integrable fastening elements and connecting devices, the structure of the modules and their manufacture can be further simplified

Claims

claims 1. A method for producing a thin film solar module with the steps  a) providing a first translucent substrate having an active region for converting solar energy  b) providing a second substrate  c) holding the first and second substrates parallel to each other at a predetermined distance from each other, wherein the active region between the first and second substrate is arranged  d) filling the gap with a liquid material  e) curing the liquid material whereby the active area is encapsulated. 2. A method of manufacturing a thin film solar module comprising the steps  f) providing a first translucent substrate having an active region for converting solar energy  g) applying a liquid material to the side of the transparent substrate with the active region, and  h) curing the liquid material whereby the active area is encapsulated. 3. The method of claim 2, wherein before step h) one or more  Fasteners for attaching the thin film solar module to a substructure and / or one or more electrical connection devices and / or one or more reinforcing elements over the side of the  transparent substrate provided with the active region and after step h) integrated into the cured material, in particular  are positively connected, are. 4. The method of claim 2 or 3, wherein in step g) a mold is provided in which the liquid material is filled. 5. The method according to any one of claims 2 to 4, wherein the steps g) and h) be performed several times to form multiple layers. 6. The method of claim 4 and 5, wherein for the plurality of layers  different forms are used. 7. The method according to any one of claims 2 to 6, wherein after step h) the  hardened material has different thicknesses, in particular in the form of reinforcing ribs. 8. The method of claim 3 and 7, wherein the one or more  Fasteners and / or the one or more electrical  Connecting devices and / or the one or more reinforcing elements are arranged so that they are after step h) in thicker areas of the cured material. 9. The method of claim 7 or 8, wherein the reinforcing ribs are at least partially arcuate. 10. The method according to any one of claims 2 to 9, wherein the liquid material is provided so that after step h) the cured material laterally at least partially beyond the edge of the substrate and / or surrounds the edge of the substrate. 11. Method according to one of claims 1 to 10, wherein the cured material has reflective properties, in particular a white color, and / or protective or stabilizing properties. 12. The method according to any one of claims 1 to 11, wherein the liquid material is a polymer material, in particular a polyurethane plastic. 13. The method according to any one of claims 1 to 12, wherein filling materials,  in particular fiber reinforcements and / or fillers for influencing thermal and / or electrical properties, are added. 14. Solar module, in particular thin-film solar module, with a first transparent substrate (1) having an active region (3) for converting solar energy, a second substrate (5) and a light-transmissive one Substrate and the second substrate connecting layer (5), wherein the active region (3) between the first and second substrate (1, 5) is arranged, characterized in that the connecting layer of a cured polymer material. 15. Solar module, in particular thin-film solar module, with a first  transparent substrate (1) having an active region (3) for converting solar energy, characterized in that the active region is covered by an encapsulation unit (29) made of a hardened polymer material which also forms the rear structure of the solar module. 16. Solar module according to claim 14 or 15, wherein the polymer material  Filling materials for influencing thermal and / or electrical  Features. 17. Solar module according to one of claims 15 or 16, wherein the  Encapsulation unit a plurality of layers, in particular with different thermal and / or electrical properties comprises. 18. Solar module according to one of claims 15 to 17, wherein the encapsulation unit (29 ') protrudes laterally at least in sections over the edge of the substrate and / or surrounds the edge of the substrate (1). 19. Solar module according to one of claims 15 to 18, wherein the encapsulation unit has different thicknesses. 20. Solar module according to one of claims 15 to 19, wherein in the  Encapsulation unit (29) one or more fasteners for  Attaching the thin film solar module to a substructure and / or one or more electrical connection devices and / or one or more reinforcing elements over the side of the transparent substrate with the active region are positively arranged.