Composite getter for manufacturing photovoltaic panels

Abstract

The present invention refers to a composite getter for thin-film photovoltaic panels which is made with a polymer having low H 2 O transmission containing one or more alkaline earth metal oxide, to a photovoltaic panel containing such a composite getter and to a method for the manufacturing of photovoltaic panels.

1 . A composite getter for a photovoltaic panel, the composite getter comprising a H 2 O sorber dispersed in a polymeric matrix having low moisture transmission, said H 2 O sorber consisting essentially of one or more alkaline earth metal oxides. 
     
     
         2 . The composite getter according to  claim 1 , in which said polymeric matrix has a H 2 O transmission lower than 10 g mm m −2  d −1  at 25° C. and 60% relative humidity. 
     
     
         3 . The composite getter according to  claim 1 , in which said polymeric matrix has a melting temperature lower than 170° C. 
     
     
         4 . The composite getter according to  claim 1 , in which said polymeric matrix has a shear force resistance of at least 0.3 N/mm 2 . 
     
     
         5 . The composite getter according to  claim 1 , in which the material forming said polymeric matrix is chosen among Ethylene-Vinyl Acetate (EVA), polyethylene of low (LDPE), medium (MDPE) and high (HDPE) density, polyether block amides (PEBA), ionomeric resins, ethylene-acrylic acid copolymers, polyvinylidene fluoride (PVDF), the PolyVinylButyral (PVB), polyvinylidene chloride (PVDC) Ethylene-Propylene Rubbers (EPR), Ethylene Propylene Diene Monomer Rubbers (EPDM) and butyl rubbers. 
     
     
         6 . The composite getter according to  claim 5  wherein said polymeric matrix comprises EVA. 
     
     
         7 . The composite getter according to  claim 5  wherein said polymeric matrix comprises EPR. 
     
     
         8 . The composite getter according to  claim 1 , in which weight percentage of H 2 O sorber inside said composite getter is between 10 and 50%. 
     
     
         9 . The composite getter according to  claim 1 , wherein said one or more alkaline earth metal oxides are chosen from CaO, MgO and their combinations. 
     
     
         10 . The composite getter according to  claim 9  wherein said one or more alkaline earth metal oxides is are CaO. 
     
     
         11 . A photovoltaic panel containing the composite getter according to  claim 1 . 
     
     
         12 . The photovoltaic panel according to  claim 11 , in which said composite getter is arranged close to an edge of the photovoltaic panel. 
     
     
         13 . A method for manufacturing of a photovoltaic panel containing one or more photovoltaic elements confined by two supports, comprising:
 joining together the supports close to an edge of the photovoltaic panel by way of the composite getter of  claim 1 ; and   thermosealing the supports.   
     
     
         14 . The method according to  claim 13 , in which said thermosealing is carried out at a temperature between 100° C. and 170° C. 
     
     
         15 . The method according to  claim 14  wherein said thermosealing is carried out in an autoclave. 
     
     
         16 . The method according to  claim 14  wherein said thermosealing is carried out in a vacuum laminator.