Procédé d'encapsulation des modules photovoltaïques type mono-verre

One of the most important steps in the photovoltaic industry is the encapsulation of the solar cells. The encapsulation consists to assemble the cells in series or parallel to allow them operate with useful currents and tensions and, at the same time, to allow their electrical isolation and protect them against atmospheric factors (humidity, rain, snow and dust) which causes corrosion, and mechanical shocks. In this paper, we present the encapsulation process we have developed at Silicon Technology Unit (UDTS) for crystalline silicon solar cells. We will focus particularly on the thermal treatment, the most critical step in the process, which decide on the quality and the reliability of the module. This thermal treatment is conducted in two steps: the lamination and the polymerisation. Several tests of EVA reticulation have been necessary for setting technological parameters as the level of vacuum, the pressure, the temperature, and the time. The quality of our process has been confirmed by the tests conducted on our modules at the European Laboratory of Joint Research Centre (JRC) of Ispra (Italy). The electrical characterisation of the modules has showed that after the encapsulation the current has been improved by a factor of 4 % to 6 % and the power gain by a factor of 4 % to 7 %. This is mainly due to the fact of using a treated glass, which reduces the reflection of the light at a level as low as 8 %. Mots clés: Module photovoltaïque - Encapsulation - Lamination - Polymérisation - EVA.