Bugnon G.,Ecole Polytechnique Federale de Lausanne |
Parascandolo G.,Ecole Polytechnique Federale de Lausanne |
Soderstrom T.,3S Swiss Solar Systems AG |
Cuony P.,Ecole Polytechnique Federale de Lausanne |
And 5 more authors.
Advanced Functional Materials | Year: 2012
To further lower production costs and increase conversion efficiency of thin-film silicon solar modules, challenges are the deposition of high-quality microcrystalline silicon (μc-Si:H) at an increased rate and on textured substrates that guarantee efficient light trapping. A qualitative model that explains how plasma processes act on the properties of μc-Si:H and on the related solar cell performance is presented, evidencing the growth of two different material phases. The first phase, which gives signature for bulk defect density, can be obtained at high quality over a wide range of plasma process parameters and dominates cell performance on flat substrates. The second phase, which consists of nanoporous 2D regions, typically appears when the material is grown on substrates with inappropriate roughness, and alters or even dominates the electrical performance of the device. The formation of this second material phase is shown to be highly sensitive to deposition conditions and substrate geometry, especially at high deposition rates. This porous material phase is more prone to the incorporation of contaminants present in the plasma during film deposition and is reported to lead to solar cells with instabilities with respect to humidity exposure and post-deposition oxidation. It is demonstrated how defective zones influence can be mitigated by the choice of suitable plasma processes and silicon sub-oxide doped layers, for reaching high efficiency stable thin film silicon solar cells. The growth of intrinsic microcrystalline silicon material at high deposition rates is studied for photovoltaic applications. The contribution of two distinct material phases on solar cell performance on textured substrates is shown. The porosity of the material is demonstrated through damp-heat experiments. Based on the developments, a single junction p-i-n microcrystalline record solar cell is presented. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Li H.-Y.,Ecole Polytechnique Federale de Lausanne |
Theron R.,Ecole Polytechnique Federale de Lausanne |
Roder G.,University of Neuchatel |
Turlings T.,University of Neuchatel |
And 5 more authors.
Polymers and Polymer Composites | Year: 2012
Appropriate encapsulation schemes are essential in protecting the active components of the photovoltaic (PV) module against weathering and to ensure long term reliability. For crystalline cells, poly(ethylene-co-vinyl acetate) (EVA) is the most commonly used PV encapsulant. Additives like peroxides and silanes are formulated in EVA encapsulants to obtain the desired properties, e.g. The desired gel content value and sufficient adhesion after the encapsulation process etc. The identification and control of volatile organic compounds (VOCs) released by the polymeric encapsulant during PV module encapsulation is important for understanding and optimizing processes in order to enhance the encapsulation quality of the manufactured modules. The authors demonstrate how gas chromatography and mass spectrometry (GC-MS) techniques can be used to help understand the curing process, mainly by identifying the VOCs emanating from EVA under the effect of temperature and pressure. The results provide chemical insights into the EVA encapsulation process, which are valuable for further optimization of the PV module manufacturing process and evaluation of its environmental impact. © Smithers Rapra Technology, 2012.
Li H.-Y.,Ecole Polytechnique Federale de Lausanne |
Perret-Aebi L.-E.,Ecole Polytechnique Federale de Lausanne |
Chapuis V.,Ecole Polytechnique Federale de Lausanne |
Ballif C.,Ecole Polytechnique Federale de Lausanne |
Luo Y.,3S Swiss Solar Systems AG
Progress in Photovoltaics: Research and Applications | Year: 2015
A high-quality encapsulation process is crucial to ensuring the performance and long-term reliability of photovoltaic (PV) modules. In crystalline Si technology-based modules, poly (ethylene-co-vinyl acetate) (EVA) is the most widely used PV encapsulant. Its encapsulation process is usually performed in a flat-bed vacuum bag laminator. In certain types of laminators, cooling press can be applied to the module cooling process after the module encapsulation, leading to a much higher cooling rate (∼100°C/min) than conventional natural cooling due to the application of water cooling circulation and mechanical pressure on the modules. In this work, the effect of the cooling press on the encapsulation properties of PV modules with EVA as the encapsulant are assessed on the aspects of residual stress in the modules, peeling strength between glass and EVA, and the resulting EVA gel content after encapsulation. The results show that the cooling press influences the encapsulation properties of PV modules. In particular by applying the cooling press after encapsulation, the residual normal stress in the Si solar cell in the encapsulated module after cooling can be reduced by as much as 22 ± 2 to 27 ± 3% depending on the EVA gel content, whereas the peeling strength between front glass and EVA is increased by ∼ 10%. This work should help the further optimization of PV module encapsulation processes aimed at improving module encapsulation quality. Copyright © 2013 John Wiley & Sons, Ltd.
3S Swiss Solar Systems AG | Date: 2014-03-19
An improved and simplified system and method for laminating sandwiched bodies, lay-ups, and more particular for the lamination of solar modules is described which can be adapted for mass production inexpensively. The present invention is simple, cost effective, reliable, and environmentally friendly in operation. A lay-up of the solar cell module is preheated before laminating, the preheating being a preferential using dedicated localised heating in a cross connector region of the module.
3S Swiss Solar Systems AG | Date: 2013-02-27
The invention relates to a holding device (1) for holding a photovoltaic module (2) and/or a solar collector module on a structure, such as a roof, platform, base, or framework, the holding device (1) comprising a support (3) and at least one holding means (4) for holding the module (2) on the support (3), wherein the holding means (4) is adapted to receive an edge of the module (2), characterized in that the holding means (4) is formed by an U-shaped profile which is an integral part of the support (3).
3S Swiss Solar Systems AG | Date: 2011-12-07
Processes and apparatus for producing laminated solar panels built up of a plurality of layers, wherein at least one layer is preheated and stores thermal energy. The at least one layer is laminated, under vacuum or in controlled gas atmosphere, with at least one other layer.
3S Swiss Solar Systems Ag | Date: 2010-01-19
A system and method for laminating a module. The system comprises a membrane adapted to apply a pressure on the module to press a plurality of layers of the module together, an intermediate member adapted to prevent gases set free during a lamination process from making contact with the membrane, and a base for retaining the module, wherein the membrane and the base are capable of forming a vacuum chamber.
3S Swiss Solar Systems AG | Date: 2014-05-28
Multi-layer stacked modules such as modules with active electronic components such as solar modules (1) are described as well as methods of making the same and apparatus for manufacture of such modules. A system and method for preparing elements of a solar module are described adapted forholding a first layer (2) (e.g. glass substrate or back sheet with or without integrated electronic active devices such as solar cells (3)), preferably vertically, so that it is flat, anda blade or squeegee (20) (e.g. having a reservoir for containing fluid encapsulant) used to apply the fluid to the first layer (2), the blade defining a gap to the outer layer.
3S Swiss Solar Systems Ag | Date: 2012-01-17
The machine has a heated plate, a conveyor for conveying the elements along a conveyor path leading across the heated plate, a top part vertically movable with respect to the heated plate, a membrane disposed on the top part and a separating film disposed between the membrane and the heated plate which can be moved synchronously with the conveyor. The separating film is divided into sections and every section is retained exclusively by a single edge oriented transversely to the conveying path by a retaining device. The sections therefore sit loosely on the elements free of tension. The membrane lies against a peripherally extending peripheral face of the top part facing the heated plate and can be moved directly onto the plane of the surface of the heated plate in order to form a closed chamber with it. Finally, the membrane is connected to a clamping device.