Solar Cell Interconnector, Solar Cell Array and Method of Interconnecting Solar Cells of a Solar Cell Array
In a solar cell interconnector ( 2′,102, 202, 302, 402 ) with at least two layers, comprising a first, substrate layer ( 20, 120, 220, 320, 420 ) and a second, electrically conductive layer ( 21, 121, 221, 321, 421 ), the first, substrate layer ( 20, 120, 220, 320, 420 ) consists of a polymeric material and the second, electrically conductive layer ( 21, 121, 221, 321, 421 ) consists of a metal material deposited on the first, substrate layer ( 20, 120, 220, 320, 420 ).
1 . A solar cell interconnector ( 2 ′, 102 , 202 , 301 , 402 ) with at least two layers, comprising a first, substrate layer ( 20 , 120 , 220 , 320 , 420 ) and a second, electrically conductive layer ( 21 , 121 , 221 , 321 , 421 ), wherein the first, substrate layer ( 20 , 120 , 220 , 320 , 420 ) consists of a polymeric material and wherein the second, electrically conductive layer ( 21 , 121 , 221 , 321 , 421 ) consists of a metal material deposited on the first, substrate layer ( 20 , 120 , 220 , 320 , 420 ).
2 . A solar cell interconnector according to claim 1 ,
characterized
in that the polymeric material of the substrate layer ( 20 , 120 , 220 , 320 , 420 ) comprises high yield strength properties, in particular a yield strength >100 MPa.
3 . A solar cell interconnector according to claim 1 or 2 ,
characterized
in that the polymeric material of the substrate layer ( 20 , 120 , 220 , 320 , 420 ) comprises a low Young's modulus, in particular a Young's modulus <10 MPa.
4 . A solar cell interconnector according to claim 1 , 2 or 3 ,
characterized
in that the metal material of the electrically conductive layer ( 21 , 121 , 221 , 321 , 421 ) comprises a low electrical resistivity, in particular a resistivity <5×10 −6 Ohm.
5 . A solar cell interconnector according to one of the preceding claims,
characterized
in that the substrate layer is resistant against particle radiation and/or ultraviolet light radiation and/or vacuum exposure.
6 . A solar cell interconnector according to one of the preceding claims,
characterized
in that the material of the electrically conductive layer ( 21 , 121 , 221 , 321 , 421 ) is selected such that the thermal expansion coefficient of the electrically conductive layer ( 21 , 121 , 221 , 321 , 421 ) is substantially the same as the thermal expansion coefficient of the substrate layer ( 20 , 120 , 220 , 320 , 420 ).
7 . A solar cell interconnector according to one of the preceding claims,
characterized
in that the material of the substrate layer ( 20 , 120 , 220 , 320 , 420 ) is polyimide or ETFE.
8 . A solar cell interconnector according to one of the preceding claims,
characterized
in that the material of the electrically conductive layer ( 21 , 121 , 221 , 321 , 421 ) is Ag or Au or Au88/Ge12 or Al.
9 . A solar cell interconnector according to one of the preceding claims,
characterized
in that the substrate layer thickness is within a range of 5 to 50 μm, preferably within a range of 10 to 25 μm, most preferably 12.5 μm.
10 . A solar cell interconnector according to one of the preceding claims,
characterized
in that the electrically conductive layer thickness is within a range of 1 to 10 μm, more preferably within a range of 1 to 5 μm.
11 . A solar cell interconnector according to claim 10 ,
characterized
in that the electrically conductive layer thickness is selected in order to minimize stresses in the electrically conductive layer ( 21 , 121 , 221 , 321 , 421 ) for a given bending radius.
12 . A solar cell interconnector according to claim 11 ,
characterized
in that the electrically conductive layer thickness is 1.9 μm for a substrate layer thickness of 12.5 μm.
13 . A solar cell array of at least two solar cells ( 101 , 101 ′; 201 , 201 ′; 301 , 301 ′; 401 , 401 ′) electrically interconnected with solar cell interconnectors ( 102 ; 202 ; 302 ; 402 ) according to one of the preceding claims, the solar cells ( 101 , 101 ′; 201 , 201 ′; 301 , 301 ′; 401 , 401 ′) each having a first surface exposed to an ionsource (S),
characterized
in that the solar cell interconnectors ( 102 ; 202 ; 302 ; 402 ) are mounted to the solar cells in such a way that the respective substrate layer ( 102 ; 220 ; 320 ; 420 ) of each interconnector ( 102 ; 202 ; 302 ; 402 ) is directed to the ion source (S) and forms thus an outer exposed surface area shielding the respective electrically conductive layer ( 121 ; 221 ; 321 ; 412 ) underneath from erosion due to sputtering.
14 . A solar cell array according to claim 13 ,
characterized
in that the solar cell interconnectors ( 302 ; 402 ) are embedded in silicone.
15 . A method of interconnecting solar cells of a solar cell array according to claim 13 or 14 , with solar cell interconnectors according to one of claims 1 to 12 ,
characterized by the steps
providing a sandwich foil roll ( 530 ) of a polymeric material substrate layer and an electrically conductive metal layer;
welding a first spot of the electrically conductive metal layer to a first solar cell contact pad;
welding a second spot of the electrically conductive metal layer to a second solar cell contact pad;
laser cutting the polymeric material substrate layer on a side of the second welding spot remote from the first welding spot and
tearing off of the remaining sandwich foil and thus cutting the metal layer.