PHOTOVOLTAIC CELL ASSEMBLY

• US 20130152996A1
• Filed: 08/29/2011
• Published: 06/20/2013
• Est. Priority Date: 09/07/2010
• Status: Active Grant

• Current Assignee: The Dow Chemical Company (Dow, Inc.)
• Original Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Inventors: DeGroot, Marty, Langlois, Marc Guy
• Granted Patent: US 9,147,788 B2
• Time in Patent Office: Days
• US Class Current: 136/244
• CPC Class Codes: H01L 31/0508 the interconnection means having a particular shape
• CPC Class Codes: H02S 20/25 Roof tile elements
• CPC Class Codes: H02S 40/36 characterised by special electrical interconnection means between two or more PV modules, e.g. electrical module-to-module connection
• CPC Class Codes: Y02B 10/10 Photovoltaic [PV]
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

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.

Claims

1. A photovoltaic cell assembly comprising:

a plurality of photovoltaic cells 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 first conductive element with a first surface and wherein the first conductive element is bent at least once along its longest dimension and wherein the at least one bend forms an angle α

from 0° and

45°

;

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.

2. The photovoltaic cell assembly according to claim 1, wherein the plurality of photovoltaic cells each further include a leading edge and a trailing edge, wherein the conductive element contacts the first photovoltaic cell at the trailing edge and the conductive element 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 element in contact with the trailing edge is from 50 to 100 percent of the length of the trailing edge.

3. The photovoltaic cell assembly according to claim 1, wherein the top collection structure composes a series of spaced apart conductive traces of a material with lower sheet resistance than the top surface.

4. The photovoltaic cell assembly according to claim 3, wherein top collection structure comprises at least one buss line.

5. 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.

6. The photovoltaic cell assembly according to claim 5, wherein the non-conductive layer portion comprises either a liquid dielectric that is cured via UV radiation or a non-conductive tape.

7. The photovoltaic cell assembly according to claim 1, wherein the conductive element is an electrically conductive adhesive tape.

8. The photovoltaic cell assembly according to claim 1, wherein the conductive element is a foil tape with an embossed surface and wherein at least 10% of the surface area of the embossed surface is in direct contact with the cell.

9. The photovoltaic cell assembly according to claim 1, wherein the adhesive is a conductive adhesive.

10. The photovoltaic cell assembly according to claim 1, wherein the adhesive is a nonconductive adhesive.

11. The photovoltaic assembly according to claim 5, wherein the buss line is located within 10 mm of the non-conductive layer and the conductive element contacts at least a portion of the buss line.

12. The photovoltaic assembly according to claim 1, wherein an overlap of the conductive element on the conductive substrate layer is at least 2.0 mm in length.

13. The photovoltaic assembly according claim 4, wherein an overlap of the conductive element overlaps at least about 10% of an area of the buss line.

14. The photovoltaic assembly according to claim 1, wherein the conductive element includes a plurality of folds.

15. A method of manufacturing a photovoltaic assembly, comprising the steps of:

(a) providing at least two solar cells, the solar cells including a photoactive portion with a top surface, a top collection structure, and a bottom conductive substrate, further wherein the cell includes a leading edge and a trailing edge;

b) providing a at least one conductive element, each with a first surface;

c) providing, at least one terminal bar;

d) placing a first cell such that a bottom surface of the conductive substrate near the leading edge of a first of the plurality of solar cells contacts a first terminal bar;

(e) connecting a first terminal bar to the first cell using a conductive component;

folding a first conductive element at least once about an axis along its longest dimension and wherein the at least one bend forms an angle α

from 0° and

45°

;

(g) applying the folded conductive element to the top of the first cell near the trailing edge and precisely placed such that the conductive element contacts the top surface of the solar con and/or the top collection structure; and

(h) placing a second cell on the folded conductive element that has already been applied to the first solar cell such that a bottom surface of the conductive substrate of the second solar cell contacts the folded conductive element, thus producing a string having a first cell and an end cell,

(i) optionally folding an additional conductive element at least once about an axis, applying the additional folded conductive element to the top of the end cell near the trailing edge and precisely placed such that the conductive element contacts the top surface of the solar cell and/or the top collection structure; and

placing an additional cell on the folded conductive element that has already been applied to the end solar cell such that a bottom surface of the conductive substrate of the additional solar cell contacts the folded conductive element, to form a string with a first cell and at least one intermediate cell and an end cell, wherein the previous end cell becomes an intermediate cell,

(j) optionally repeating step (i),

(k) placing a second terminal bar such that it contacts the top surface of the last of the end solar cell on a buss line that is part of the collection structure edge of the end solar cell;

(l) connecting the second terminal bar to the last cell using a conductive component.