Substrate and electrode for solar cells and the corresponding manufacturing process

Abstract

Solar cells use as substrates glass ( 23 ) coated with a transparent conductive layer ( 21 ), able to collect the electric power generated by the solar cell. This layer ( 21 ), normally a TCO, have limited conductivity, implying the use of current collector lines applied in a complex manner. The conductivity of the conductive layer ( 21 ) is increased by the application of a structure, in particular a grid, of thin conductive lines ( 22 ) inserted in grooves on the glass surface ( 23 ) or directly applied on this, followed by a TCO layer coating ( 21 ). This highly conductive grid ( 22 ) collects the electricity from the TCO layer ( 21 ) and directs it to the periphery of the cell. Both glass substrates are sealed by a process employing a precursor of glass surrounding the entire perimeter of the substrate. The glass precursor is heated to its melting point, by a laser, completely sealing the two substrates of the module.

1 . A substrate and electrode for solar cells comprising:
 a. one insulated layer ( 23 , 6 );   b. one electrode conductive layer of one or more transparent conductive oxides ( 21 , 8 ), applied over the referred insulated substrate ( 23 , 6 );   characterized by including additionally a conductive mesh/grid ( 22 , 2 ) between the described insulated layer ( 23 , 6 ) and the described electrode conductive layer of one or more transparent conductive oxides ( 21 , 8 ).   
     
     
         2 . The substrate and electrode for solar cells according to  claim 1 , wherein the described insulated substrate ( 23 , 6 ) include grooves and the described conductive mesh ( 22 , 2 ) is embedded in the described grooves. 
     
     
         3 . The substrate and electrode for solar cells according to  claim 1 , wherein the described grooves have depth and width of less than 500 μm, in particular less than 200 μm, more particularly of less than 200 μm. 
     
     
         4 . The substrate and electrode for solar cells according to  claim 1 , wherein the described conductive mesh is applied on the surface of the insulated substrate layer ( 23 ,  6 ). 
     
     
         5 . The substrate and electrode for solar cells according to  claim 1 , wherein the described conductive lines have width between 100 μm and 1000 μm. 
     
     
         6 . The substrate and electrode for solar cells according to  claim 5 , wherein the described conductive lines have thickness less than 10 μm, in particular less than 1 μm and at least 200 nm thick. 
     
     
         7 . The substrate and electrode for solar cells according to  claim 1 , wherein the described conductive mesh ( 22 ) is a square format or a hexagonal mesh, or a fractal structure, or an interdigital structure. 
     
     
         8 . The substrate and electrode for solar cells according to  claim 1 , wherein the rows and columns of the mesh/grid ( 22 ,  2 ) are separated from each other between 1 mm and 20 mm. 
     
     
         9 . The substrate and electrode for solar cells according to  claim 1 , wherein the described conductive mesh ( 22 , 2 ) is composed by zinc, or aluminum, or silver, or silicon, or copper, or any combination of these materials. 
     
     
         10 . A solar cell comprising the electrode and substrate according to  claim 1 . 
     
     
         11 . A solar collector system that comprises solar cells ( 1 ,  25 ) according to  claim 10 . 
     
     
         12 . A solar collector system according to  claim 11  wherein the conductive mesh ( 2 ) is the same for a plurality of solar cells ( 1 ). 
     
     
         13 - 31 . (canceled)