Photovoltaic cell assembly
The present invention is premised upon an improved photovoltaic cell assembly that include at least plurality of photovoltaic cells with a photoactive portion with a top surface, a top collection structure on the top surface and an opposing conductive substrate layer on a side of the photoactive portion opposite the top surface. Also including a first conductive element with a first surface and wherein the first conductive element is bent at least once and wherein the first surface is in contact with the top collection structure and/or the top surface of a first photovoltaic cell and the opposing conductive substrate layer of an adjacent second photovoltaic cell; further wherein at least a portion of the first surface is held in contact to the cells by an adhesive.
1. A photovoltaic cell assembly comprising:
a plurality of photovoltaic cells each comprising:
a photoactive portion with a top surface;
a top collection structure on the top surface, and
an opposing conductive substrate layer on a side of the photoactive portion opposite the top surface;
a conductive foil with a first surface and wherein the conductive foil is folded at least once along its longest dimension forming at least one bend, and wherein the at least one bend forms an angle α from 0° and 45°;
wherein the first surface is in direct contact with the top collection structure and/or the top surface of a first photovoltaic cell and the opposing conductive substrate layer of an adjacent second photovoltaic cell; further wherein at least a portion of the first surface is held in contact to the cells by an adhesive; and
wherein the plurality of photovoltaic cells each further include a leading edge and a trailing edge, wherein the conductive foil contacts the first photovoltaic cell at the trailing edge and the conductive foil contacts the opposing conductive substrate layer of the adjacent second photovoltaic cell at the leading edge, further wherein the leading edge of the adjacent second photovoltaic cell overlaps the trailing edge of the first photovoltaic cell and the length of the conductive foil in contact with the trailing edge is from 50 to 100 percent of the length of the trailing edge.
2. The photovoltaic cell assembly according to claim 1 , wherein the top collection structure comprises a series of spaced apart conductive traces of a material with lower sheet resistance than the top surface.
3. The photovoltaic cell assembly according to claim 2 , wherein the top collection structure comprises at least one bus line.
4. The photovoltaic cell assembly according to claim 1 , wherein at least a portion of a peripheral edge portion of the cells include a non-conductive layer portion.
5. The photovoltaic cell assembly according to claim 4 , wherein the non-conductive layer portion comprises either a liquid dielectric that is cured via UV radiation or a non-conductive tape.
6. The photovoltaic cell assembly according to claim 1 , wherein the conductive foil is an electrically conductive adhesive tape.
7. The photovoltaic cell assembly according to claim 1 , wherein the conductive foil is a foil tape with an embossed surface and wherein at least 10% of a surface area of the embossed surface is in direct contact with the cell.
8. The photovoltaic cell assembly according to claim 1 , wherein the adhesive is a conductive adhesive.
9. The photovoltaic cell assembly according to claim 1 , wherein the adhesive is a non-conductive adhesive.
10. The photovoltaic cell assembly according to claim 1 , wherein an overlap of the conductive foil on the conductive substrate layer is at least 2.0 mm in length.
11. The photovoltaic cell assembly according to claim 3 , wherein an overlap of the conductive foil overlaps at least about 10% of an area of the bus line.
12. The photovoltaic cell assembly according to claim 1 , wherein the conductive foil includes a plurality of folds.
13. The photovoltaic cell assembly of claim 3 , wherein the at least one bus line is located within 10 mm of a peripheral edge of the cell at the trailing edge.
14. The photovoltaic cell assembly of claim 3 , wherein the conductive foil contacts at least a portion of the bus line of the collection structure.
15. The photovoltaic cell assembly of claim 1 , wherein the conductive element is a metal foil with an embossed surface;
wherein at least 40 percent of a surface area of the embossed surface of the metal foil is in direct contact with the top collection structure or top surface of the first photovoltaic cell and at least 40 percent of a surface area of the embossed surface of the metal foil is in direct contact with the opposing conductive substrate layer of an adjacent second photovoltaic cell.
16. The photovoltaic cell assembly of claim 1 , wherein the angle of the fold is 0 and the conductive element is folded upon itself.
17. The photovoltaic cell assembly of claim 3 , wherein the conductive element is a metal foil with an embossed surface;
wherein at least 10 percent of a surface area of the embossed surface of the metal foil is in direct contact with the top collection structure or top surface of the first photovoltaic cell and at least 10 percent of a surface area of the embossed surface of the metal foil is in direct contact with the opposing conductive substrate layer of an adjacent second photovoltaic cell.
18. The photovoltaic cell assembly of claim 17 , wherein the angle of the fold is 0 and the conductive element is folded upon itself.
19. The photovoltaic cell assembly of claim 17 , wherein the fold separates a first half and a second half of the conductive foil and the first half and second half are separated by the angle from 0° to 45°.