EP2718980A1

EP2718980A1 - Solar module

Info

Publication number: EP2718980A1
Application number: EP12713690.1A
Authority: EP
Inventors: Andreas Sznerski; Holger Schumacher
Original assignee: Saint Gobain Glass France SAS; Compagnie de Saint Gobain SA
Current assignee: Saint Gobain Glass France SAS; Compagnie de Saint Gobain SA
Priority date: 2011-06-07
Filing date: 2012-04-03
Publication date: 2014-04-16
Also published as: KR20140040792A; CN103583000A; US20140174508A1; JP2014522631A; WO2012167965A1

Abstract

The present invention relates to a solar module (1) comprising at least: a carrier layer (2) and, arranged thereon one above another, a first intermediate layer (3), at least one solar cell (4), a second intermediate layer (5) and a front sheet (6), a circumferential edge reinforcement (7) arranged above the front sheet (6), an interspace (51) formed by a circumferential overhang (13) of the carrier layer (2) and a circumferential overhang (14) of the edge reinforcement (7) over the front sheet (6), wherein the interspace (51) has a sealant (50).

Description

solar module

The invention relates to a solar module and a method for producing a solar module.

Photovoltaic layer systems for the direct conversion of solar radiation into electrical energy are well known. The materials and the arrangement of the layers are coordinated so that incident radiation from one or more semiconducting layers with the highest possible radiation yield is converted directly into electrical current. Photovoltaic and extensive coating systems are called solar cells.

Solar cells contain semiconductor material in all cases. The largest known efficiencies of more than 20% are achieved with high-performance solar cells made of monocrystalline, polycrystalline or microcrystalline silicon or gallium arsenide. More than 80% of the currently installed solar cell power is based on crystalline silicon. Thin film solar cells require carrier substrates to provide sufficient mechanical strength. Due to the physical properties and the technological handleability, thin film systems with amorphous, micromorphous or polycrystalline silicon, cadmium telluride (CdTe), gallium arsenide (GaAs), copper indium (gallium) selenide sulfide (Cu (ln, Ga) (S, Se) ₂ ), copper-zinc-tin-sulfo-selenide (CZTS) and organic semiconductors are particularly suitable for solar cells. The pentenary semiconductor Cu (In, Ga) (S, Se) ₂ belongs to the group of chalcopyrite semiconductors, which are often referred to as CIS (copper indium diselenide or sulfide) or CIGS (copper indium gallium diselenide, copper indium gallium disulfide or copper indium gallium disulfoselenide). S in the abbreviation CIGS stands for selenium, sulfur or a mixture of both chalcogens.

An electrical circuit of several solar cells is referred to as a photovoltaic or solar module. The circuit of solar cells is permanently protected from environmental influences in known weather-resistant structures. Usually, two slices of low-iron soda-lime glass and adhesion-promoting polymer films are connected to the solar cells to form a weather-resistant solar module. The solar modules can be integrated into a circuit of several solar modules via junction boxes or connection housings. The circuit of solar modules is connected via known power electronics with the public utility network or a self-sufficient electrical power supply.

Flat roofs of warehouses or industrial plants have a large, exposed and unpaved surface. They are therefore particularly well suited for the installation of photovoltaic systems. The roof of flat roofs is usually made of metal sheets and, for example, trapezoidal sheets. Flat roofs usually have only a low roof pitch of 2% to 17.6% and have only a low load-bearing capacity of, for example, 75 kg / m ² .

Solar modules according to the prior art, in which the solar cells are laminated between two slices of soda-lime glass, have a high basis weight of, for example, 18 kg / m ² . They are therefore not suitable for mounting on flat roofs with low load capacity.

For the production of lightweight solar modules with a weight per unit area of less than 12 kg / m ² windscreens made of thin glass or plastics are usually combined with carrier layers made of a lightweight but nevertheless warp-resistant material. At the same time, the front screen and the carrier layer must be sufficiently impermeable to moisture or water vapor in order to protect the solar cells and bus bars inside the solar module against corrosion. Suitable materials for the carrier layers are, for example, glass fiber reinforced plastics or metal layers.

US 2010/00651 16 A1 discloses a thin-glass solar module with a basis weight of 5 kg / m ² to 10 kg / m ² . The thin-glass solar module comprises a carrier layer, solar cells and a front pane of very thin, chemically hardened glass. The very thin glass is flexible. The windshield is so flexible that the impact energy of a hailstone is absorbed by the carrier layer on the back of the solar module in the legally required hail impact test.

EP 1 860 705 A1 discloses a stable, self-supporting solar module, which is arranged on its externa ßeren areas in a mounting frame. The mounting frame has notches through which liquids located on the solar module can drain. US 4,830,038 A describes a solar module which is supported and encapsulated by an elastomer. The elastomer is cast in an injection molding process around the back, sides and part of the front.

DE 10 2009 014 348 A1 discloses a solar module made of a transparent adhesive layer, in which the solar cells connected via cell connectors are embedded. Above is a transparent, UV-stable, thin front layer. At the back is a load-bearing sandwich element, consisting of a core layer and polyurethane fiber-bonded layers. In the supporting sandwich element fasteners and an electrical junction box are integrated.

EP 2 237 324 A1 describes a solar module with an L-shaped frame. One leg of the L-shaped frame is glued to the solar module. The second leg forms a spacer to a roof or support structure.

WO 03/050891 A2 discloses a solar module with a first substrate, a second substrate and at least one photovoltaic element between the substrates. The border between the first and second substrates is sealed with a moisture resistant material.

DE 102 31 401 A1 describes a photovoltaic module with a light-transmitting substrate, a first sealing polymer layer, a photocell, a second sealing polymer layer and a weatherproof film. The weatherproof film contains a moisture-proof layer and a gas-tight layer, the gas-tight layer consisting of polyphenylene sulfide.

A critical entry point for the penetration of moisture into the interior of the solar module remains the lateral leading edge of the solar module between the windscreen and the carrier layer.

The object of the present invention is to provide a solar module with an improved sealing of the side entry edges against moisture. The improved Solar module should be particularly lightweight and suitable for installation on a flat roof.

The object of the present invention is achieved by a solar module according to claim 1. Preferred embodiments will become apparent from the dependent claims. Furthermore, the invention comprises a method for producing a solar module. A use of the solar module according to the invention is evident from further claims.

The solar module according to the invention comprises

A carrier layer and, arranged one above the other, a first intermediate layer, at least one solar cell, a second intermediate layer and a front pane, and

• an edge reinforcement, which is arranged above the windscreen.

The carrier layer has a circumferential projection over the front screen and the edge reinforcement has a circumferential projection on the front screen. The space between the projection of the carrier layer and the projection of the edge reinforcement has a sealant.

The terms "arranged one above the other" or "arranged above" describe a congruent or a section-wise arrangement in the sense of the invention.

In an advantageous embodiment of the solar module according to the invention, the carrier layer has a circumferential projection over the front pane of at least 0.3 cm, preferably from 0.3 cm to 5 cm and particularly preferably from 0.3 to 1 cm. In a further advantageous embodiment of the solar module according to the invention, the edge reinforcement has a circumferential projection over the windshield of at least 0.3 cm, preferably from 0.5 cm to 5 cm and particularly preferably from 1 to 2 cm. The projection of the edge reinforcement and the projection of the carrier layer over the front pane are preferably of the same size, so that the intermediate space has an approximately rectangular cross-sectional area. This has the particular advantage that in the case of a shock load, both the carrier layer and edge reinforcement can absorb acting forces uniformly. The edge enhancement has several essential functions. By the edge reinforcement additional protection of the outer edge of the solar module is achieved, for example by impact during transport or assembly.

Furthermore, a clearance is formed by the supernatant of the carrier layer and the projection of the edge reinforcement over the windshield, which has a sealant. The sealant serves as a moisture barrier. The sealant is mechanically protected by the carrier layer and the edge reinforcement, so that the moisture barrier is permanently maintained.

As a sealant, in principle, all plastics are suitable that are UV-stable and weather-resistant and have sufficient water and water vapor impermeable properties. The sealant preferably contains polyurethane (PU), polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), polyamide (PA), high density polyethylene (HDPE), low density polyethylene (LDPE), acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate (PC), styrene butadiene (SB), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), thermoplastic elastomers or a butyl, acrylic, bitumen or silicone based adhesive and / or mixtures thereof.

The edge reinforcement comprises one or more layers, preferably of metal, glass, rubber, plastic or glass fiber reinforced plastic. The edge reinforcement particularly preferably comprises the material of the carrier layer. The carrier layer advantageously has a coefficient of thermal expansion adapted to the solar module and the front pane. As a result, no or only small mechanical stresses occur due to different thermal expansion of the materials of the solar module.

The edge reinforcement may preferably be polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), polyamide (PA), high density polyethylene (HDPE), low density polyethylene (LDPE), acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate (PC), styrene butadiene (SB), polymethyl methacrylate (PMMA), polyurethane (PUR), polyethylene terephthalate (PET) and / or mixtures thereof. The thickness of the edge reinforcement is preferably at least 0.5 mm and more preferably 1 mm to 5 mm and the front window is raised. The externa ßere range of a glass front panel particularly vulnerable to chipping or Ausmuschelungen of the glass, for example, when hitting a hailstone in the hail impact test. Increasing the edge reinforcement via the windscreen creates a protected area. A hailstone with a diameter of, for example, 25 mm can not penetrate into the particularly susceptible to damage edge area of the windshield because of the increase in the edge reinforcement. The necessary minimum thickness of the edge reinforcement can be determined by simple tests in the hail impact test.

In a further advantageous embodiment of a solar module according to the invention, the edge reinforcement covers a peripheral edge region of the windscreen over a width b of at least 0.2 cm, more preferably from 0.5 cm to 5 cm and most preferably from 1 cm to 2 cm. The edge reinforcement is preferably glued in the peripheral edge region with the front pane, for example by a butyl, acrylic or silicone adhesive or a double-sided adhesive tape. The bonding results in a stable gap allowing easy filling of the gap with the sealant.

Since the edge reinforcement overlaps the windshield in sections, a peripheral border forms, which surrounds the windshield in an annular manner. In the case of rainfall or snowmelt, water may accumulate in the area between the windshield and the edge reinforcement. The water can not drain due to the peripheral edge reinforcement. The standing water accumulation promotes the formation of algae. In addition, water can penetrate the moisture seals of the solar module in permanent or long-lasting exposure. Furthermore, this area collects dirt, sand and dust that can not be washed away by rainwater.

The accumulation of water and dirt at the transition between windshield and edge reinforcement affects especially solar modules on roofs, which have only a low roof pitch, so-called flat roofs. An important aspect of the present invention therefore comprises water drainage channels which are incorporated in the edge reinforcement. Rainwater or melt water can drain off through the water drainage channels. The effluent water can carry dirt, sand and dust with it and keep the windscreen of the solar module free from contamination.

In an advantageous embodiment of a solar module according to the invention, the edge reinforcement at each corner of the solar module at least one water drainage channel, which connects the inside of the edge reinforcement with the Au ßenseite the edge reinforcement. Outside of the edge reinforcement here means the side of the edge reinforcement, which is located on the outside of the solar module. Inside the edge reinforcement means the side opposite the outside of the edge reinforcement.

In an advantageous embodiment of the solar module according to the invention, the edge reinforcement on each circumferential Au ßenseite the solar module at least one water drainage channel.

The width of the water gutter is advantageously chosen so that a hailstone with a diameter of 25 mm at a speed of 23 m / s with a central or lateral impact on the water gutter, the windscreen not damaged. The width of the water drainage channel is dependent on the thickness of the edge reinforcement, that is, the height h of the increase in the edge reinforcement over the windscreen, and can be determined by simple experiments. In an advantageous embodiment of the solar module according to the invention, the water drainage channel has a width of 0.5 mm to 5 mm, preferably from 2.5 mm to 5 mm.

The bus bars are led out of the solar module through openings in the edge reinforcement, the windscreen and / or the carrier layer. Above the respective opening a connection housing is arranged. The bus bars are electrically connected in the connection housing with a connection cable. The connection is preferably made via plugs, contact pins, contact tongues, spring element, crimp connections, solder joints, welds or other electrical line connections. In an advantageous embodiment of the solar module according to the invention, the connection housing covers the complete opening. The connection housing and / or the opening and recess cavity formed can be closed by a grout. The casting agent seals the solar module against moisture penetration and contains, for example, polyurethane, acrylic, silicone or other suitable sealing materials.

The openings in the edge reinforcement, the front screen or the carrier layer are preferably rectangular, square, or circular, although all forms are suitable, within which the bus bar can be conveniently arranged.

In an advantageous embodiment of the invention, the solar cell comprises a monocrystalline or polycrystalline solar cell, preferably with a doped semiconductor material such as silicon or gallium arsenide.

In an alternative embodiment of the invention, the solar cell comprises a thin-film solar cell, preferably amorphous, micromorphous or polycrystalline silicon, cadmium telluride (CdTe), gallium arsenide (GaAs), copper indium (gallium) sulfide sulfide (Cu (ln , Ga) (S, Se) ₂ ), copper-zinc-tin-sulfo-selenide (CZTS) or organic semiconductors.

Alternatively, the solar cell comprises a tandem cell of two superimposed solar cells of different types, for example a crystalline silicon solar cell in combination with a thin-film solar cell, an organic solar cell or an amorphous silicon solar cell.

In an advantageous embodiment of the invention, the solar cell comprises all solar cells, which are themselves brittle and / or their support material and break or damage by slight bending or punctual load with low forces. A slight bending here means, for example, a curvature with a radius of curvature of less than 1500 mm. A point load with low forces here means, for example, an indentation by the impact of a hailstone with a diameter of 25 mm and a speed of 23 m / s in a hail impact test. Damage here means a deterioration of the photovoltaic properties of the solar cell due to mechanical damage to the semiconductor material, the carrier material or electrical Line connections, for example by a short circuit or a line break. The damage to the solar cell reduces the efficiency of the solar cell, for example, immediately after the impact by more than 3%. Usually, a further deterioration of the efficiency due to microcracks occurs over time.

The first and / or second intermediate layer contains an adhesive layer, preferably one or more adhesive films, particularly preferably ethylene vinyl acetate (EVA), polyvinyl butyral (PVB), ionomers, thermoplastic polyurethane (TPU), thermoplastic elastomer polyolefin (TPO), thermoplastic elastomer (TPE) or other materials with appropriate adhesive and moisture-proofing properties. The thickness of an adhesive layer may vary widely and is preferably from 0.2 mm to 1 mm and in particular 0.4 mm.

The externa ßeren dimensions of the solar module according to the invention can vary widely and are preferably from 0.6 m x 0.6 m to 1, 2 m x 2.4 m. A solar module according to the invention preferably contains from 6 to 100 individual solar cells or solar cell arrays. The area of a single solar cell is preferably from 153 mm × 153 mm to 178 mm × 178 mm.

The windscreen contains a material that is largely transparent to sunlight, preferably glass, particularly preferably flat glass, float glass, quartz glass, borosilicate glass, solar glass, soda-lime glass, or polymers, preferably polyethylene, polypropylene, polycarbonate, polymethyl methacrylate and / or mixtures thereof. The faceplate may also comprise a film of a polymer, preferably of a fluorinated polymer, more preferably of ethylene-tetrafluoroethylene (ETFE), polytetrafluoroethylene (PTFE), fluorinated ethylene-propylene (FEP) or perfluoroalkoxyalkane (PFA) and / or mixtures thereof , The thickness of the polymer film can vary widely and is preferably from 10 μm to 250 μm.

The windscreen particularly preferably contains low-iron soda-lime glass with a particularly high transparency for sunlight of more than 90% in a wavelength range of 300 nm to 1500 nm.

The windscreen preferably contains thermally toughened or tempered glass with a preload of 30 MPa to 120 MPa, and preferably from 32 MPa to 85 MPa. The The front pane may have additional additional coatings, such as anti-reflection layers, anti-adhesive layers or anti-scratch layers. The windscreen can have a one-sided or two-sided microstructuring or nanostructuring, which for example reduces the reflection of incident sunlight. The windscreen may be a single disk or a composite disk of two or more disks. The composite pane may contain further layers, such as transparent thermoplastic adhesive layers or plastic layers.

In an advantageous embodiment of the invention, the windscreen must be sufficiently stable and unyielding to protect the underlying solar cells from damage. Possible causes of damage include hailstorm, wind load, snow load or bending during assembly as well as entry by persons or animals or the fall class of a tool. At the same time the windscreen should be as thin as possible and have a low weight to be suitable for mounting on flat roofs with low wearing capacity.

As experiments by the inventors have shown, solar modules according to the invention with windscreens of partially prestressed or tempered soda lime glass with a thickness of at least 0.9 mm meet the technical requirements with respect to torsional rigidity and stability.

In particular, windscreens according to the invention with a thickness of at least 0.9 mm offer sufficient protection for crystalline solar cells contained in the solar module in the hail impact test according to IEC 61215. The hail impact test comprises fitting the front side of the solar module with hailstones having a diameter of 25 mm and a speed of 23 m / s. The windscreen according to the invention has sufficient stability and intransigence to absorb the energy of the impact of a hailstone without damaging the crystalline solar cell inside the solar module.

Alternatively, the windscreen can be flexible and resilient under load. The forces that occur can then be absorbed by the carrier layer. Deflecting windshields, that is windshields made of flexible materials or very thin front windows are not suitable for solar modules with brittle or crystalline solar cells. The crystalline solar cell would break due to the bending of the windscreen. This usually leads to the destruction of a large area of the solar cell, even if the windscreen is not damaged.

The thickness of the windscreen significantly determines the weight of the solar module. In order to provide a solar module as lightweight as possible, which is suitable for installation on a flat roof with only a low load capacity, glass windshields are preferably used with a thickness of at most 2.8 mm. An inventive solar module with a front glass with a thickness of 2.8 mm has a basis weight of about 10 kg / m ² . Such a solar module is suitable for mounting on flat roofs with a low load reserve of at least 10 kg / m ² .

A windscreen according to the invention is usually not damaged by a hail impact test, unless the hail impact occurs in a peripheral area. The margins of glass panes are particularly sensitive to chipping and Ausmuschelungen. The edge area of the windscreen can be stabilized by an edge reinforcement. The edge reinforcement according to the invention protects the edge region of the windshield from damage in the hail impact test.

An important aspect of the invention comprises the adaptation of the thermal expansion coefficients of the windshield and carrier layer: different coefficients of thermal expansion of the windshield and carrier layer can lead to a different temperature expansion when the temperature changes. A different temperature expansion of the front screen and carrier layer can lead to a bending of the solar module and thus to damage of the crystalline solar cells. Temperature changes of more than 100 ° C occur, for example, in the lamination of the solar module or when heating the solar module on the roof.

The second coefficient of thermal expansion, that is to say the thermal expansion coefficient of the windscreen, is preferably from 8 × 10 ^-6 / K to 10 × 10 ^-6 / K and for partially tempered soda-lime glass, for example from 8 × 10 ^-6 / K to 9 , 3 x 10 ^{~ 6} / K. In an advantageous embodiment of the solar module according to the invention, the difference between the first thermal expansion coefficient of the carrier layer of a solar module according to the invention and the second coefficient of thermal expansion of the windscreen <300%, preferably <200% and particularly preferably <50% of the second coefficient of thermal expansion of the windshield.

In an advantageous embodiment of the solar module according to the invention, the carrier layer contains a glass fiber reinforced plastic. The glass fiber reinforced plastic contains, for example, a multi-layer glass fiber fabric which is embedded in a casting resin molded from unsaturated polyester resin. The glass content of the glass fiber reinforced plastic is preferably from 30% to 75%, and more preferably from 50% to 75%.

In an advantageous embodiment of the solar module according to the invention, the carrier layer has a first coefficient of thermal expansion of 7 × 10 ^-6 / K to 35 × 10 ^-6 / K, preferably from 9 × 10 ^-6 / K to 27 × 10 ^-6 / K and especially preferably from ^{9x10 -6} / K to ^{20x10 -6} / K.

In an alternative embodiment of the solar module according to the invention, the difference between the first thermal expansion coefficient and the second thermal expansion coefficient is <17%, preferably <12% and particularly preferably <7% of the second coefficient of thermal expansion.

In an advantageous embodiment of the solar module according to the invention, the carrier layer contains a metal foil having a first coefficient of thermal expansion of 7.3 × 10 -6 / K to 10.5 × 10 -6 / K. The first intermediate layer may include a stacking sequence of at least a first adhesive layer, an insulating layer and a second adhesive layer. The insulating layer preferably contains a solid, insulating film, for example of polyethylene terephthalate (PET). The insulating layer has the task of isolating the bus bars and the back of the solar cells from the electrically conductive metal foil of the carrier layer. The metal foil preferably contains a stainless steel, preferably a stainless steel of the EN material number 1 .4016, 1 .4520, 1 .451 1, 1 .4017, 1 .41 13, 1 .4510, 1 .4516, 1 .4513, 1 .4509, 1 .4749, 1 .4724 or 1. 4,762th Another aspect of the invention comprises a flat roof with

• a roof covering with a roof slope of 1% (0.6 °) to 23.1% (13 °),

At least one solar module according to the invention, arranged on the roof skin, wherein the roof skin and the solar module according to the invention by at least one adhesive layer and / or connecting means are connected to each other at least in sections.

In an advantageous embodiment of the flat roof according to the invention, the roof inclination of 2% (1, 1 °) to 17.6% (10 °), preferably from 5% (2.9 °) to 17.6% (10 °) and especially preferably from 5% (2.9 °) to 8.8% (5 °).

The adhesive layer, with which the solar module according to the invention and the roof cladding are connected, preferably contains an acrylate adhesive, a butyl adhesive, a bitumen adhesive or a silicone adhesive or a double-sided adhesive film. The connecting means preferably contain screw, clamp or rivet and / or support rails, guide rails or eyelets made of plastic or metal, such as aluminum, steel or stainless steel.

In an advantageous embodiment of the flat roof according to the invention, the roof skin contains a plastic, preferably polymethyl methacrylate (PMMA, Plexiglas®), polyester, bitumen, polymer modified bitumen, polyvinyl chloride (PVC) or thermoplastic olefin-based elastomers (TPO), preferably with a flat, chambered or corrugated Profile.

In an alternative embodiment, the roof skin contains a metal sheet, preferably a metal sheet of copper, aluminum, steel, galvanized and / or plastic-coated steel. The metal sheet has, for example, a trapezoidal profile and is referred to below as a trapezoidal sheet. Above or below the roof skin, further layers may be arranged, for example layers for thermal insulation. The layers for thermal insulation preferably contain plastics or plastic foams, for example of polystyrene or polyurethane.

The screwing of the solar module with the roof skin of a flat roof according to the invention is preferably carried out in a region of the edge reinforcement of the solar module and in particular in the region of the supernatant of the carrier layer over the windshield. this has the particular advantage that no hole in the windscreen must be introduced. Inserting a hole in the glass front panel is a complex and expensive process step. Furthermore, the stability of the windshield is reduced by the hole.

A further aspect of the invention comprises a method for producing a solar module according to the invention, wherein at least the sealing means in the intermediate space between the projection of the edge reinforcement over the front pane and the projection of the carrier layer over the front pane is filled.

An advantageous embodiment of the method for producing a solar module according to the invention comprises at least:

A carrier layer and a first intermediate layer, at least one solar cell, a second intermediate layer and a front pane arranged thereon one above the other are laminated, wherein the carrier layer is arranged with a circumferential projection over the front pane,

• an edge reinforcement is arranged with a projection over the windscreen above the windscreen and

• The gap between the projection of the edge reinforcement over the windscreen and the projection of the carrier layer over the windscreen is filled by a sealant.

For the purposes of the invention, lamination encompasses all methods known per se for bonding the layer structure of a solar cell, preferably by the action of heat and / or pressure, for example by autoclave processes, calender processes or vacuum bag processes.

In an advantageous embodiment of the method according to the invention, the edge reinforcement is arranged in sections on a circumferential edge region of the windshield and glued to the windshield, for example by a butyl, acrylic or silicone adhesive or a double-sided adhesive tape. This has the particular advantage that a stable gap is formed, which can be filled in the second process step by the sealant. In an alternative embodiment of the method according to the invention, the edge reinforcement is pressed or held, for example by a frame on the windshield. In the second process step, the resulting gap is filled by the sealant. The sealant glues the edge reinforcement with the rest of the solar module, so that the edge reinforcement is firmly connected to the solar module.

As a sealant, in principle, all plastics are suitable that are UV-stable and weather-resistant and have sufficient water and water vapor impermeable properties.

In a preferred embodiment of the method according to the invention, the sealant contains a 1-component, 2-component or multi-component plastic. However, thermoplastic elastomers are suitable as sealants which are introduced into the intermediate space in the liquid, hot state and cure there.

The sealant is preferably introduced in liquid or pasty form, by hand or with a mechanical device in the gap and cures there.

The sealant preferably contains a 1-component polyurethane sealant which cures with atmospheric moisture to form a permanently elastic elastomer, for example Sikkaflex 222, from Sika Deutschland GmbH.

Another aspect of the invention comprises the use of a solar module according to the invention on a flat roof, preferably on a metal flat roof, a building or a vehicle for locomotion by water, on land or in the air. For the installation of solar modules according to the invention are particularly flat roofs of warehouses, industrial plants and garages or shelters such as carports suitable whose roofs have a large, exposed and unshaded surface and have a low roof pitch.

A further aspect of the invention comprises the use of a solar module according to the invention on a flat roof with a roof pitch of 1% (0.6 °) to 23.1% (13 °), preferably from 2% (1, 1 °) to 17.6% (10 °), more preferably from 5% (2.9 °) to 17.6% (10 °) and most preferably from 5% (2, 9 °) to 8.8% (5 °).

Brief description of the drawings

The invention will be explained in more detail with reference to a drawing and an example. The drawing is not completely true to scale. The invention is not limited by the drawing in any way.

Show it:

FIG. 1 A is a schematic representation of an exemplary embodiment of a solar module according to the invention,

1 B shows a cross-sectional view with a view of the sectional plane A from FIG. 1 A, FIG. 2 shows a cross-sectional view of an alternative exemplary embodiment of a solar module according to the invention with a view of the sectional plane A from FIG.

3 is a cross-sectional view of an alternative embodiment of a solar module according to the invention with a view of the sectional plane A of Figure 1 A,

FIG. 4 shows a cross-sectional illustration of an alternative exemplary embodiment of a solar module according to the invention with a view of the sectional plane A from FIG. 1A,

Figure 5 is a cross-sectional view of an alternative embodiment of a solar module according to the invention with a view of the sectional plane A of Figure 1 A and

FIG. 6 shows a detailed flow chart of the method according to the invention.

Detailed description of the drawings

In FIG. 1A, a solar module according to the invention designated as a whole by the reference numeral 1 is illustrated. FIG. 1 A shows a perspective view of the front side, that is to say of the side facing the sun, of the solar module 1. The back of the Larmoduls 1 is in the context of the present invention, the side facing away from the front side. As Au ßenseiten I, II, III, IV of the solar module 1 are referred to in the following, the outer ßeren edge of the front and the back circumferential sides. On the outer sides I, II, III, IV of the solar module 1 are the so-called leading edges, where moisture and water vapor can penetrate particularly easily into the solar module 1.

The solar module 1 comprises a plurality of series-connected solar cells 4, of which eight are shown in FIG. The solar cells 4 are in this example monocrystalline silicon solar cells. Each solar cell has a nominal voltage of, for example, 0.63 V, so that the solar module 1 has a total nominal voltage of, for example, 5 V. The voltage is led out via bus bars 21 to two connection housings 20 in the edge region of side III of solar module 1. In the connection housings 20, the electrical line connection to the connecting lines, which are not shown in the figures for reasons of clarity. The connecting cables are connected to a power grid or other solar modules.

The bus bars 21 are electrically connected to the solar cells 4. A bus bar 21 usually contains a metallic band, for example a tinned copper band with a thickness of 0.03 mm to 0.3 mm and a width of 2 mm to 16 mm. Copper has proven itself for such busbars, as it has a good electrical conductivity and good processability to films. At the same time, the material costs are low. Other electrically conductive materials can also be used which can be processed into films. Examples of these are aluminum, gold, silver or tin and alloys thereof.

FIG. 1B shows a cross-sectional view with a view of the sectional plane A from FIG. 1A. The solar module 1 according to the invention comprises a layer structure comprising carrier layer 2, first intermediate layer 3, solar cell 4, second intermediate layer 5 and front pane 6. The carrier layer 2 has a circumferential overhang 13 over the front pane 6 of, for example, 0.5 cm. The solar module 1 according to the invention has an edge reinforcement 7. The edge reinforcement 7 is arranged in the region 9 over a width b of, for example, 5 mm above the windshield 6. The edge reinforcement 7 projects beyond the front pane 6 in the region 14 by a length c of, for example, 0.5 cm. The gap 51 between the supernatant 13 of the carrier layer 2 on the windshield 6 and the supernatant 14 of the edge reinforcement 7 via the windscreen 6 is filled with a sealant 50. The sealing means 50 is preferably arranged over the entire circumferential gap on the sides I, II, III and IV of the solar module 1. The sealant 50 contains, for example, a polyurethane sealant, for example Sikaflex 222, from Sika Deutschland GmbH. The sealing means 50 reliably seals the solar cells 4 in the interior of the composite of carrier layer 2, first 3 and second intermediate layer 5 and front pane 6 against moisture.

The edge reinforcement 7 is glued to the windshield 6. The bond seals the area between edge reinforcement 7 and front screen 6 and stabilizes the gap 51 during the introduction of the sealant 50.

The carrier layer 2 of the solar module 1 contains, for example, a glass fiber reinforced plastic. The glass fiber reinforced plastic contains, for example, a multi-layer glass fiber fabric which is embedded in a casting resin molded from unsaturated polyester resin. The carrier layer 2 has, for example, a glass content of 54%, a basis weight of 1.65 kg / mm ² and a thickness of 1 mm.

Above the carrier layer 2, a first intermediate layer 3 is arranged. The first intermediate layer 3 contains, for example, an adhesive film of ethylene-vinyl acetate (EVA) with a thickness of 0.4 mm.

Above the first intermediate layer 3, a plurality of crystalline solar cells 4 are arranged, one of which is shown partially in FIG. 1B. The crystalline solar cell 4 consists for example of a monocrystalline silicon solar cell with a size of 156 mm x 156 mm. All solar cells 4 of a solar module 1 according to the invention are electrically conductively connected to one another via bus bars and, depending on the intended use, connected in series or in parallel. Furthermore, blocking or bypass diodes can be integrated into the solar module 1. Above the solar cells 4, a second intermediate layer 5 is arranged, which contains, for example, an adhesive film of ethylene-vinyl acetate (EVA) with a thickness of 0.4 mm.

Above the second intermediate layer 5, a front screen 6 is arranged. The windshield 6 contains, for example, a low-iron soda-lime glass with a thickness of 0.9 mm to 2.8 mm and in particular of 1 mm. The soda-lime glass is thermally partially prestressed with a prestress of, for example, 40 MPa. Part toughened glass differs from toughened glass by a slower cooling process. The slower cooling process results in less stress differences between the core and the surfaces of the glass. The flexural strength of semi-tempered glass is between that of unbiased and tempered glass. Part-tempered glass has a high residual capacity in the event of a break and is therefore particularly suitable for crash-proof glazing on buildings or in the roof area.

As a windshield 6 are equally suitable films or discs of ethylene tetrafluoroethylene (ETFE), polycarbonate or other plastics that are sufficiently transparent, weather resistant and UV-stable and have a sufficiently high density against moisture.

The carrier layer 2 has a first thermal expansion coefficient of, for example, 27 × 10 ^-6 / K. The windshield 6 has a second coefficient of thermal expansion, for example 9 × 10 ^-6 / K. The difference between the first and second coefficients of thermal expansion is 18 × 10 ^-6 / K and thus 200% of the second thermal expansion coefficient.

The carrier layer 2 may likewise contain a metal foil, for example a foil made of a stainless steel such as stainless steel, material number 1 .4016 with a thickness of 0.3 mm.

The carrier layer 2 has in this embodiment, a circumferential projection 13 on the windscreen 6. The width a of the supernatant is preferably from 0.5 cm to 10 cm and for example 2 cm. The edge reinforcement 7 is arranged above the overhang 13 of the carrier layer 2 and above an edge region 9 of the front pane 6. The Width b of the edge region 9 is preferably 0.5 cm to 10 cm and for example 1 cm. The edge reinforcement 7 is preferably glued in the edge region 9 with the front pane, for example with a double-sided adhesive tape.

Two bus bars 21 are led out in the region of the intermediate space 51 on the outer side III of the solar module 1 between the first intermediate layer 3 and the second intermediate layer 5. The bus bars 21 are connected at one end to the solar cell 4. The bus bars 21 are disposed within the gap 51 and in an opening 17 of the edge reinforcement 7. Above the opening 17 of the edge reinforcement 7, a connection housing 20 is arranged, in which there is an electrical line connection between bus bar 21 and an outer connecting line, which is not shown in the figure.

In the edge reinforcement 7 more water drainage channels 8 are arranged in the form of recesses. The water drainage channels 8 connect the inner edge 10 of the edge reinforcement 7 with the outer edge 1 1 of the edge reinforcement 7. The width of the water drainage channels 8 is from 1 mm to 5 mm and for example 3 mm. The width of the water drainage channels 8 and the thickness of the edge reinforcement 7 are chosen so that a hailstone with a diameter of 25 mm does not damage the windscreen in the hail impact test. This can be determined in the context of simple experiments.

In the case of rain or snow melting, the water arising on the windshield 6 can flow off via the water drainage channels 8.

In the exemplary embodiment of a solar module 1 according to the invention shown in FIG. 1A, a water drainage channel 8 is arranged in each corner 12 of the solar module 1. The water drainage channels 8 are arranged, for example, at an angle of 45 ° to the outer sides I, II, III, IV of the solar module 1. In addition, each of the outer sides I, II, III and IV one or more further water drainage channels 8 have, which is not shown in Figure 1A. The water drainage channels 8 on the outer sides I, II, III, IV of the solar module 1 can be arranged, for example, at right angles to the outer sides I, II, III, IV of the solar module 1.

The solar module 1 according to the invention has a basis weight of about 5.6 kg / m ² . FIG. 2 shows a cross-sectional view of an alternative exemplary embodiment of a solar module 1 according to the invention with a view of the sectional plane A from FIG. 1A. In this embodiment, two additional edge reinforcements 15.1, 15.2 are arranged in the intermediate space 51. The additional edge reinforcements 15.1, 15.2 contain on the outer side III of the solar module 1 recesses in which the bus bar 21 is arranged and is guided to the opening 17 in the edge reinforcement 7. The additional edge reinforcements 15.1, 15.2 stabilize the spacing of the intermediate space 51 between the edge reinforcement 7 and the carrier layer 2.

FIG. 3 shows a cross-sectional view of an alternative exemplary embodiment of a solar module 1 according to the invention with a view of the sectional plane A from FIG. 1 A. In this exemplary embodiment, the bus bar 21 is guided around the windshield 6. The opening 17, through which the bus bar 21 is guided into the connection housing 20, is arranged above the windscreen 6 in the region 9. This arrangement has the particular advantage that the outer edge region of the solar module 1 can be used for fastening the solar module 1, for example in a U-shaped guide rail. The edge reinforcement 7 is glued in the region 9 with the windshield 6, for example by an elastic double-sided adhesive tape, which is not shown in the figure. On the one hand, the adhesive tape is yielding, so that the bus bar 21 can be arranged underneath or above it. On the other hand, the tape serves to seal against water and moisture.

FIG. 4 shows a cross-sectional view of an alternative exemplary embodiment of a solar module 1 according to the invention with a view of the sectional plane A from FIG. 1A. In this embodiment, the windscreen 6 has an opening 16, within which the bus bar 21 is arranged. Above the opening 16 of the windshield 6 is the opening 17 of the edge reinforcement 7 and the terminal housing 20. Through the opening 16, the windscreen 6 is weakened. This weakening is compensated by the glued to the windshield 6 edge reinforcement 7. Since the bus bar 21 is led directly from the interior of the solar module 1 through the openings 16 and 17 in the connection housing 20, a particularly good sealing of the exit point of the bus bar 21 takes place. Figure 5 shows a cross-sectional view of an alternative embodiment of a solar module 1 according to the invention with a view of the sectional plane A of Figure 1 A. In this embodiment, the support layer has an opening 18, within which the bus bar 21 is arranged. Below the opening 18 of the carrier layer 2, the connection housing 20 is arranged. Since the connection housing 20 and thus also the outer connection lines are located on the rear side of the solar module 1, the connection housing 20 and connection lines are protected against external influences and in particular against influences on the front side of the solar module 1.

FIG. 6 shows a detailed flow chart of the method according to the invention.

The solar module 1 according to the invention has a number of advantages over solar modules according to the prior art. The edge reinforcement 7 according to the invention protects the fracture-sensitive outer edge of the windshield 6 from damage during transport and installation. At the same time, the edge reinforcement 7 according to the invention allows the almost unimpeded outflow of water during rain or snowmelt. The sealant 50 according to the invention seals the interior of the solar module 1 against moisture and water vapor. Furthermore, the inventive method for producing the solar module 1 is particularly simple and inexpensive to perform. At the same time solar module 1 is particularly lightweight with a basis weight of less than 12 kg / m ² and suitable for use on a flat roof with a low roof pitch.

This result was unexpected and surprising to the skilled person.

Show it:

1 solar module

2 carrier layer

3 first intermediate layer

4 solar cell

5 second intermediate layer

6 windscreen

7 edge reinforcement

8 water drainage channel

9 edge area of the windscreen 6

10 inside of the edge reinforcement 7

1 1 Outside of edge reinforcement 7

12 corner of the solar module 1

13 protrusion of the carrier layer 2 on the windshield. 6

14 projection of the edge reinforcement 7 on the windshield. 6

15.1, 15.2 edge reinforcement

16 opening in the windscreen 6

17 opening in the edge reinforcement layer 7.2

18 opening in the carrier layer 2

20 connection housing

21, 21 .1, 21 .2 busbars

50 sealants

51 space between the supernatant 13 of the support layer 2 and the supernatant 14 of the edge reinforcement 7 on the windshield 6 a width of the protrusion 13 of the support layer 2 on the windshield 6 b width of the edge region. 9

c width of the supernatant 14 of the edge reinforcement 7 over the

Windscreen 6

A cutting plane

I, II, III, IV side, Au ßenseite the solar module. 1

Claims

claims

1 . Solar module (1), comprising:

A carrier layer (2) and, arranged one above the other, a first intermediate layer (3), at least one solar cell (4), a second intermediate layer (5) and a front pane (6),

A circumferential edge reinforcement (7), which is arranged above the front pane (6),

A gap (51) which is formed by a circumferential projection (13) of the carrier layer (2) and a circumferential projection (14) of the edge reinforcement (7) over the front screen (6),

wherein the intermediate space (51) has a sealing means (50).

2. Solar module (1) according to claim 1, wherein the carrier layer (2) has a circumferential projection (13) and / or the edge reinforcement (7) a circumferential projection (14) over the front panel (6) of at least 0.3 cm, preferably from 0.3 cm to 5 cm and more preferably from 0.3 cm to 1 cm.

3. Solar module (1) according to any one of claims 1 or 2, wherein the edge reinforcement (7) at least one peripheral edge region (9) of the windshield (6) of at least 0.2 cm, preferably from 0.5 cm to 5 cm and especially preferably covered from 1 cm to 2 cm.

4. solar module (1) according to one of claims 1 to 3, wherein the edge reinforcement (7) at each corner (12) and / or on each Au ßenseite (I, II, III, IV) of the solar module (1) at least one water outlet trough (8) which connects the inner side (10) and the outer side (1 1) of the edge reinforcement (7).

5. Solar module (1) according to claim 4, wherein the water drainage channel (8) has a width of 0.3 mm to 5 mm, preferably from 2 mm to 4 mm.

6. Solar module (1) according to one of claims 1 to 5, wherein at least one bus bar 21 in an opening (16) of the windshield (6), in an opening (17) of the edge reinforcement (7) and / or in an opening (18 ) of the carrier layer (2) is arranged.

7. Solar module (1) according to one of claims 1 to 6, wherein the sealing means (50) polyurethane (PU), polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), polyamide (PA), high density polyethylene (HDPE ), Low density polyethylene (LDPE), acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate (PC), styrene butadiene (SB), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), thermoplastic elastomers or an adhesive on butyl, acrylic , Bitumen or silicone base and / or mixtures thereof.

8. Solar module (1) according to one of claims 1 to 7, wherein the solar cell (4) is a monocrystalline or polycrystalline, doped semiconductor material, preferably of silicon or gallium arsenide, a thin-film solar cell, preferably of amorphous, micro-morphemic or polycrystalline silicon, Cadmium telluride (CdTe), gallium arsenide (GaAs), copper indium (gallium) selenide sulfide (Cu (In, Ga) (S, Se) ₂ ), copper zinc tin sulfo selenide ( CZTS), organic semiconductors, or a tandem cell.

9. Solar module according to one of claims 1 to 8, wherein the windscreen (6)

Glass, preferably flat glass, float glass, quartz glass, borosilicate glass, solar glass, soda-lime glass, or polymers, preferably polyethylene, polypropylene, polycarbonate, polymethyl methacrylate and / or mixtures, or fluorinated polymers, preferably ethylene-tetrafluoroethylene (ETFE), polytetrafluoroethylene (PTFE), fluorinated ethylene-propylene (FEP) or perfluoroalkoxylalkane (PFA) and / or mixtures thereof.

10. Solar module according to claim 9, wherein the front window (6) thermally teilvorgespanntes or tempered glass having a thickness of 0.9 mm to 2.8 mm.

1 1. Solar module according to one of claims 1 to 10, wherein the carrier layer (2) has a first thermal expansion coefficient and the front screen (6) has a second coefficient of thermal expansion and the difference between the first coefficient of thermal expansion and the second thermal expansion. coefficient of friction of the windscreen (6) <300% and preferably <17%, the second coefficient of thermal expansion.

12. Solar module according to one of claims 1 to 1 1, wherein the carrier layer (2) contains a glass fiber reinforced plastic having a first coefficient of thermal expansion of 7.3 x 10 ^"6 / K to 35 x 10 ^{" 6} / K.

13. A method for producing a solar module (1) according to any one of claims 1 to 12, wherein at least the intermediate space (51) between the supernatant (14) of the edge reinforcement (7) and the supernatant (13) of the carrier layer (2) via the windscreen (6) is filled by a sealant (50).

14. Use of a solar module (1) according to one of claims 1 to 12 on a flat roof (30), preferably on a metal flat roof, a building or a vehicle for locomotion by water, on land or in the air.

15. Use of a solar module (1) according to claim 14 on a flat roof with a roof pitch of 1% to 23.1%, preferably from 2% to 17.6% and more preferably from 5% to 8.8%.