MXPA00009481A - Photovoltaic modules with composite bodies - Google Patents

Abstract

The invention relates to photovoltaic modules, characterised in that they contain one or more layers which each consist of a multilayered composite body containing at least one layer of polycarbonate and at least one layer of a fluorine-containing polymer. The invention also relates to the use of the inventive photovoltaic modules.

Description

PHOTOVOLTAIC MODULES COMPRISING COMPOSITE BODIES Field of Invention The present invention relates to photovoltaic modules containing one or more layers consisting of a multilayer composite body, and refers to the use thereof for a fixed or mobile power generation.

Background of the Invention Glass is used almost exclusively as the coating for rigid photovoltaic modules. Glass coatings are characterized by their poor mechanical loading capacity.

Clear plastic coatings are known in place of glass. These generally consist of polycarbonate plates. These are used when a very high mechanical load is required, as in the case of sailboats, for example. The modules are inserted in Ref: 123517 the structure super or e floor, that to the possibility that the modules are stepped on and can not be removed. The modules comprise polycarbonate as a coating which has the disadvantage of having a very poor weatherability. On the other hand, these are permeable to water vapors, so photovoltaic modules can corrode. This results in these modules having to be replaced after short periods.

It is already known that fluoropolymer sheets can be used as transparent coating films in light, in flexible photovoltaic modules. Both pure fluoropolymers, such as polyvinyl fluoride (PVF), and modified fluoropolymers, such as copolymers of filled ether (ETFE), are used herein as sheets. Examples of sheets that are used for the aforementioned purposes include Tediar® or Tefzel®, both of which are marketed by the company Du Pont.

Three-layer sheets comprising a polyvinyl fluoride / polyester / polyvinyl fluoride layer structure are also used as reinforcement sheets for photovoltaic modules. An example of it is the Icosolar®, a commercial product of the company Isovolta.

The photovoltaic modules that are covered with fluoropolymer sheets have only a limited mechanical load capacity. The sheets of fluoropolymer exhibit a poor printing capacity.

Description of the invention.

The fundamental object of the present invention is to provide photovoltaic modules having improved properties. The object is essentially to improve the printing capacity compared with photovoltaic modules that are fluoropolymer coated. The object is also to improve the mechanical load capacity. This can be ridding the weight and increasing the fracture resistance compared to the photovoltaic modules with glass covers. Weather resistance / water vapor tightness and scratch resistance can be improved compared to photovoltaic modules that have polycarbonate as a coating. The resistance to low temperatures of photovoltaic modules that have a fluoropolymer as a coating can be increased.

This object according to the invention is realized by photovoltaic modules which are characterized in that they contain one or more layers consisting of a multilayer composite body, which contains at least one layer of polycarbonate and at least one layer of fluorine-containing polymer.

The photovoltaic modules according to the invention have numerous advantages.

Photovoltaic modules based on polycarbonate / fluoropolymer composite bodies (eg injection molded or extruded solid plates or hollow chamber plates) exhibit improvements in the mechanical load capacity at low weights compared to photovoltaic modules that have a glass coating. This low weight is particularly advantageous for the use of photovoltaic modules for the generation of mobile power. Compared with polycarbonate coated, these have improved weather resistance and improved water vapor impermeability. Its resistance to scratching is high.

Furthermore, the requirement of good printing capacity of the outer layer or, if necessary, of the hidden lower layers is satisfied. On the other hand, modules of this type can have three-dimensional shapes, which correspond to an increased requirement for the freed architecture design. In addition, functions that facilitate installation can be integrated. Additionally, modules of this type can be exposed to the high temperatures that photovoltaic modules having fluoropolymer layers can have.

The photovoltaic modules according to the invention contain at least one layer consisting of a multi-layer composite body, which contains at least one polycarbonate layer and at least one layer of a fluoride-containing polymer. In addition, it contains at least one layer consisting of one or more solar cells. Solar cells can be connected in parallel or in series.

The photovoltaic modules according to the invention are constructed of a plurality of layers, wherein the upper layer, which faces light, consists of a composite body containing at least one layer of polycarbonate and at least one layer of a polymer which contains fluorine.

The solar cells of the photovoltaic modules according to the invention consist of inorganic and / or organic photosensitive materials, for example monocrystalline silicon, polycrystalline silicon or amorphous silicon, or of selenium of cuprous indium or cadmium telluride, or of organic dyes or of Graetzel cells. The Solar cells are preferably made of silicon.

The polycarbonate-fluoropolymer composite bodies according to the invention may consist of two or more layers.

A preferred embodiment of polycarbonate-fluoropolymer composite bodies according to the invention is a two-layer structure comprising a polycarbonate layer and a fluoropolymer layer. A layer of a bonding agent can be placed between these two layers. The layers may also contain other additives, such as UV absorbers, for example.

Another preferred embodiment of the polycarbonate-fluoropolymer composite bodies according to the invention is a three-layer system comprising a fluoropolymer layer, a polycarbonate layer and an ethylene-vinyl acetate copolymer layer. The layers of binding agents can be placed between said layers. The layers may also contain other additives, such as UV absorbers, for example.

This layer structure is particularly advantageous for the production of photovoltaic modules according to the invention, since the solar cells can be laminated in the ethylene-vinyl acetate copolymer layer without having to use a separate ethylene-copolymer film. vinyl acetate.

The polycarbonate fluoropolymer composite bodies according to the invention can be produced, for example, by extrusion, co-extrusion or lamination. These can be coated by plasma deposition, for example (CVD (chemical vapor deposition), or by sputtering, vacuum metallizing, vapor assisted ion deposition, lacquering, etc.

The polycarbonate-fluoropolymer composite bodies according to the invention can have a thickness from 1 mm up to a few centimeters. The polycarbonate / fluoropolymer ratio by weight can be in the range from 1000: 1 to 1: 1000. This ratio is preferably from 100: 1 to 1: 100, and more preferably from 20: 1 to 1:20.

The polycarbonates that are used in the polycarbonate-fluoropolymer composite bodies are those that are based on the diphenols of formula (II) where A represents a single bond, a C1-C5 alkylene, a C2-C5 alkylidene, a C5-C6 cycloalkylidene, -S- or -SO2-, represent chlorine or bromine, is 0, 1 or 2, and is 1 or 0, or alkyl substituted dihydroxyphenylcycloalkanes of formula (III) where R7 and R8, independently of each other, each means hydrogen, a halogen, preferably chlorine or bromine, a C 1 -C 4 alkyl, a C 5 -C 6 cycloalkyl, a C 6 -C 6 aryl, or preferably phenyl, or a C 7 aralkyl C 12, preferably a phenyl-Ca-Ca alkyl, particularly benzyl, m is an integer of 4, 5, 6 or 7, preferably 4 or 5, R9 and Rio can be selected individually by a Z e, independently of one another, they mean hydrogen or a C1-C6 alkyl, and Z means carbon, with the proviso that R and R10 simultaneously indicate an alkyl on at least one Z atom.

Examples of suitable diphenols of formula (II) include hydroquinone, resorcinol, 4,4'-d? -hydroxydiphenyl, 2,2-b? S- (4-h? Drox? Phen?) -propane (this is bisphenol A ), 2, 4 -bis- (-h? Drox? Phenyl) -2-methylbutane, 1, 1-b? S- (4-h? Drox? Phen?) -cyclohexane, 2, 2-b? S - (3-chloro-4-hydroxy-phenyl) -propane, and 2,2-bis- (3, 5-d? Bromo-4-h? Drox? -phenyl) -propane.

Preferred diphenols of formula (II) are 2,2-b? S- (4-H? Drox? Phen? L) -propane, 2,2-b? S- (3,5-d? Chloro-4-h? Drox? Phenyl) -propane yl , lb? s- (4-hydroxyphenyl) -cyclohexane.

Preferred diphenols of formula (III) are 1,1-b? S- (4-h? Drox? Phen? L) -3,3-d? Met? Lc? Clohexane, 1, 1-b? S- ( 4-H? Drox? Phen?) -3, 3, 5-trimet? Lc? Clohexane yl, lb? S- (4-h? Drox? Phen?) -2,4,4-tr? Met? l-cyclopentane.

Polycarbonates that are suitable in accordance with the invention include both opolicarbonates and copolycarbonates. A mixture of thermoplastic polycarbonates as defined above is also appropriate.

The polycarbonates can be produced in a known manner from the diphenols with phosgene by the process of joining the phase or with phosgene by the process in homogeneous phase, which is the period of the pyridine process or by a transesterification process in the melt starting of the diphenols and esters of carboxylic acids, wherein the molecular weight can be adjusted in a known manner by a corresponding amount of terminator chains. These production processes are described, for example, by H.? Chnell in "Chemistry and Physics of Polycarbonates", Polymer Reviews, volume 9, pages 31-76, Interciencia publications, 1964.

Examples of suitable chain terminators include phenol, p-chlorophenol, p-tert. -butyl phenol or 2, 4,6-tribromophenol, and also include long-chain alkylphenols such as 4- (1, 1, 3,3-tetra-methylbutyl) -phenol or monoalkylphenols or dialkylphenols which they comprise a total of 8 to 20 C atoms in their substituted alkyls, such as 3,5-di-tert. -butylphenol, p-iso-octylphenol, p-tert. -octylphenol, p-dodecylphenol, 2- (3, 5-dimethyl-heptyl) -phenol and 4- (3,5-dimethyl-heptyl) -phenol.

The amount of chain terminators is generally between 0.5 and 10 mol% with respect to the sum of the diphenols of the formulas (II) and / or (III) that are used in each case.

The polycarbonates which are suitable according to the invention have average molecular weights (pM: average weight, as measured by ultracentí leakage or light scattering, for example) of 10,000 to 200,000, preferably 18,000 to 80,000.

The polycarbonates which are suitable according to the invention can be branched in the known manner, preferably by the incorporation of 0.05 to 2 mol%, with respect to the sum of the diphenols used, of trifunctional compounds or of compounds with greater functionality that three, for example, compounds that contain three or more than three phenolic groups.

Apart from the bisphenol A homopolycarbonate, the preferred polycarbonates are the copolycarbonates of bisphenol A with above 15 mol%, with respect to the molar sum of the diphenols, of 2,2-bis- (3,5-dibromo-4-hydroxyphenyl) ) -propane, and the copolycarbonates of bisphenol A with above 60% by mol, with respect to the molecular sum of the diphenols, of 1,1-bis- (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane.

The polycarbonates can be particularly or completely replaced by aromatic polyester carbonates. The aromatic polycarbonates may also contain polysiloxane blocks. The production thereof is described in US-A 3 821 325, for example.

The fluoropolymers that are used are polymers in which the hydrogen atoms of the polyethylene carbon chain are completely or partially replaced by fluorine atoms, or are chlorine derivatives. fluoro-chloro derivatives thereof or derivatives of the copolymers thereof.

A preferred embodiment of the photovoltaic modules according to the invention has the following structure. The side facing the light consists of a composite body according to the invention. Beneath this is a layer of solar cells fixed in a polymer. This polymer can be an ethylene-vinyl acetate copolymer, a polyurethane or a polysiloxane, for example. An ethylene-vinyl acetate copolymer is preferably used herein. The embedding process is preferably carried out so that the solar cells are laminated between two sheets of ethylene-vinyl acetate copolymer. Underneath this there is a support for layers of glass, metal, epoxy resin mat or other plastics. The other layers of the photovoltaic modules are preferably also assembled simultaneously with the lamination within the solar cells, to form a complete module in a single production step. The photovoltaic modules can be bordered by a metal frame or other materials. The modules Photovoltaics can also resist directly, that is, without a reinforcing layer, or other substrates, for example on the frame of the glider wings.

Another preferred embodiment of the photovoltaic modules according to the invention has the following structure. The side facing the light consists of a composite body according to the invention. Below this is a layer of solar cell fixed in a polymer. This polymer can be an ethylene-vinyl acetate copolymer, a polyurethane or a polysiloxane, for example. An ethylene-vinyl acetate copolymer is preferably used herein. The assembly process is preferably carried out in such a way that the solar cells are laminated between two sheets of ethylene-vinyl acetate copolymer. Below this there is a second composite body layer in accordance with the invention. The photovoltaic modules can be bordered by a metal frame or other materials.

The photovoltaic modules according to the invention can be flat or non-planar.

The photovoltaic modules according to the invention can also be a component of which hybrid modules are terminated, which are used to generate electric power and heat.

The photovoltaic modules according to the invention can be used for the generation of fixed and mobile energy. The photovoltaic modules can be used, for example, for solar energy vehicles such as solar powered automobiles, for aircraft or airships, for ships or ships, houseboats and caravans, for toys, for advertising campaigns, for example, illuminated panels, for the illumination of guides, for automatic ticket machines for parking lots, for roadway lighting systems and leisure areas, in the field of security, for facade modules or roof modules, or for noise barrier modules .

In all the aforementioned uses, the photovoltaic modules according to the invention can be used either to cover the total energy requirements of the object, that is, to supply the energy it requires for its impulse, for example, a solar energy car, or the photovoltaic modules according to the invention can only provide part of the energy requirement of the corresponding objects , for example, for the lighting of a vehicle.

The photovoltaic modules according to the invention can be produced by a recessing process or by melting processes, for example.

The process of vacuum lamination using ethylene vinyl acetate (EVA) as an adhesive film has been proven to be an important recessing process. In this process, the photovoltaic modules are assembled in a vacuum chamber under the effect of reduced pressure and / or overpressure to form a "lamina". The EVA melts during this process and around the solar cells on all sides. After the cross-linking procedure, the solar cells are substantially protected from moisture, external material, etc. The other layers of the photovoltaic module are also preferably assembled simultaneously with the lamination of the solar cells in the EVA layer, to form a complete module in a production step.

As an alternative to this process, a melting process has been developed for the production of large area modules. In this process, the solar cells are inserted between the two outer layers, for example, bodies composed of polycarbonate-f polyvinyl fluoride. The intermediate space is filled by melting, for example, with a ream of polyurethane of ba to viscosity or a polysiloxane. This process is also appropriate for the production of small modules. If the accommodation is built correspondingly, it is possible to carry out an integration in an optimal way.

Examples In order to investigate the printing capacity, the following tests are carried out on the printing capacity of five different sheets: The printing of the sheets was carried out using two different simple component screen printing inks: 1. Ink A for screen printing (a high-temperature ink: Noriphan® HTR, bonding vehicle: copolycarbonate based on bisphenol A and 1,1-bis- (4-hydroxyphenyl) -3-3-5-trimethylcyclohexane (trade name APEC ®HT), 2. Ink B for screen printing (standard ink: Jet 200, supplied by Prdll, linking vehicle: polyacrylate resin and cellulose derivatives).

The printing was carried out once by means of a 100 mesh fabric. This was followed by drying by itself at room temperature. The test was performed for 43 hours after printing.

The cross-cut adhesion test was carried out in accordance with DIN 53 151, ISO 2 09.

The evaluation corresponding to the cross-cut parameter 0 is the best evaluation. To this the graduation of the cut parameter 5 continued as the worst valuation. The classification of the cross-cut parameter samples 0 to the cross-cut parameter 5 was made in comparison to images in accordance with the Standard.

The adhesive tape test was run as follows: a cross cut is made, and an 18 mm wide adhesive tape is subsequently pasted into the ink layer and pressed using a rubber roller at a moderate pressure; the adhesive tape is then completely removed to a moderate relationship. The evaluation is carried out analogously to the cross-cut test.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Having described the invention as above, the content of the following is claimed as property.

Claims (11)

Claims

1. Photovoltaic modules, characterized in that they contain one or more layers consisting of a multi-layer composite body, containing at least one polycarbonate layer and at least one layer of a fluorine-containing polymer.

2. The photovoltaic modules according to claim 1, characterized in that the multilayer composite bodies consist of a polycarbonate layer and a layer of a fluorine-containing polymer and optionally of a layer of a binding agent therebetween.

3. The photovoltaic modules according to claim 1, characterized in that the multi-layer composite bodies consist of a layer of a fluorine-containing polymer, a polycarbonate layer, an ethylene-vinyl acetate copolymer layer and optionally of agent layers. of union between them.

4. The photovoltaic modules according to any of claims 1 to 3, characterized in that the polycarbonate layers or the fluorine-containing polymer layers, or both, contain UV absorbers.

5. The photovoltaic modules according to any of claims 1 to 4, characterized in that one of the multi-layer composite bodies forms the upper layer, which faces the light, of the photovoltaic module.

6. The photovoltaic modules according to one of claims 1 to 5, characterized in that the polycarbonate is a polycarbonate based on bisphenol A.

7. The photovoltaic modules according to any of claims 1 to 5, characterized in that the polycarbonate is a copolycarbonate based on bisphenol A and up to 60% in mol, with respect to the molar sum of diphenols, of 1, 1-bis (4-) hydroxyphenyl) -3,3,5-trimethylcyclohexane.

8. The photovoltaic modules according to any of claims 1 to 7, characterized in that the fluorine-containing polymer is polyvinyl fluoride.

9. The photovoltaic modules according to any of claims 1 to 8, characterized in that at least one of the multilayer composite bodies is printed.

10. The use of the photovoltaic modules according to any of claims 1 to 9, for the generation of fixed or mobile energy.

11. A composite body, characterized in that it comprises a fluoropolymer layer, a polycarbonate layer and an ethylene-vinyl acetate copolymer layer, wherein the layers of bonding agent can be placed between the layers and where the layers can also contain other layers. additives