Interconnects for solar cell devices

• US 7,259,322 B2
• Filed: 01/09/2006
• Issued: 08/21/2007
• Est. Priority Date: 01/09/2006
• Status: Expired due to Fees

• Current Assignee: Solyndra Residual Trust
• Original Assignee: Solyndra Incorporated
• Inventors: Gronet, Chris M.
• Primary Examiner(s): Nguyen; Nam
• Assistant Examiner(s): FICK, ANTHONY D
• Application Number:
  US11/329,296
• Publication Number:
  US 20070157962A1
• Time in Patent Office: 589 Days
• Field of Search: 136243-265
• US Class Current: 136/246
• CPC Class Codes: H01L 31/035281 Shape of the body
• CPC Class Codes: H01L 31/0392 including thin films deposited on metallic or insulating substrates ; characterised by specific substrate materials or substrate features or by the presence of intermediate layers, e.g. barrier layers, on the substrate textured substrates H01L31/02366
• CPC Class Codes: H01L 31/03923 including AIBIIICVI compound materials, e.g. CIS, CIGS
• CPC Class Codes: H01L 31/03925 including AIIBVI compound materials, e.g. CdTe, CdS
• CPC Class Codes: H01L 31/0547 comprising light concentrating means of the reflecting type, e.g. parabolic mirrors, concentrators using total internal reflection
• CPC Class Codes: Y02E 10/52 PV systems with concentrators
• CPC Class Codes: Y02E 10/541 CuInSe2 material PV cells

Abstract

A solar cell assembly comprising a plurality of elongated solar cells, each respective solar cell comprising (i) a core configured as a first electrode, (ii) a semiconductor junction circumferentially disposed on the core, (iii) a transparent conductive oxide (TCO) layer disposed on the semiconductor junction, and (iv) an elongated counter-electrode disposed lengthwise on a first side of the respective solar cell and extending outward from the TCO layer. On a second side of each cell, approximately opposite the counter-electrode, is a notch or other disruption extending through the semiconductor junction and the transparent oxide layer, thereby exposing the core of the solar cell. The solar cell assembly may further comprise conductive internal reflectors configured between a first and second elongated solar cell in the plurality of solar cells such that a portion of the solar light reflected from the respective internal reflector is reflected onto the solar cells.

Claims

1. A solar cell assembly comprising:

(A) a plurality of elongated solar cells, each elongated solar cell in said plurality of elongated solar cells comprising;

an elongated conductive core configured as a first electrode,

a semiconductor junction disposed on said elongated conductive core;

a transparent conductive oxide layer disposed on said semiconductor junction; and

an elongated counter-electrode attached to and extending from the transparent conductive oxide layer,

wherein the elongated conductive core of each respective elongated solar cell in the plurality of elongated solar cells has an exposed portion not covered by the semiconductor junction and the transparent conductive oxide layer of the respective elongated solar cell, and wherein the counter-electrode of a first elongated solar cell in said plurality of elongated solar cells is in electrical communication with the exposed portion of the conductive core of a second elongated solar cell in said plurality of elongated solar cells that is adjacent to the first elongated solar cell; and

(B) an internal reflector that is configured between and in contact with the counter-electrode of the first elongated solar cell and the exposed portion of the conductive core of the second elongated solar cell, such that a portion of the solar light reflected from the internal reflector is reflected onto the first and second elongated solar cells.

2. The solar cell assembly of claim 1, wherein the internal reflector has a hollow core.

3. The solar cell assembly of claim 1, wherein the internal reflector comprises a plastic casing with a layer of reflective material deposited on said plastic casing.

4. The solar cell assembly of claim 3, wherein the layer of reflective material is polished aluminum, aluminum alloy, silver, nickel or steel.

5. The solar cell assembly of claim 1, wherein the internal reflector is a single piece made out of a reflective material.

6. The solar cell assembly of claim 5, wherein the reflective material is polished aluminum, aluminum alloy, silver, nickel or steel.

7. The solar cell assembly of claim 1, wherein the internal reflector comprises a plastic casing onto which is layered a metal foil tape.

8. The solar cell assembly of claim 7, wherein the metal foil tape is aluminum foil tape.

9. The solar cell assembly of claim 1, wherein a cross-sectional shape of the internal reflector is astroid.

10. The solar cell assembly of claim 1, wherein

a cross-sectional shape of the internal reflector is four-sided;

and

a side of said four-sided cross-sectional shape is parabolic.

11. The solar cell assembly of claim 1, wherein

a cross-sectional shape of the internal reflector is four-sided;

and

a side of said four-sided cross-sectional shape is concave.

12. The solar cell assembly of claim 1, wherein

a cross-sectional shape of the internal reflector is four-sided;

and

a side of said four-sided cross-sectional shape is circular or elliptical.

13. The solar cell assembly of claim 1, wherein

a cross-sectional shape of the internal reflector is four-sided;

and

a side of said four-sided cross-sectional shape defines a diffuse surface on said internal reflector.

14. The solar cell assembly of claim 1, wherein the internal reflector has a first edge and a second edge, wherein said first edge and said second edge run lengthwise along said internal reflector;

and wherein

(i) the first edge of the internal reflector contacts the first elongated solar cell; and

(ii) the second edge of the internal reflector contacts the second elongated solar cell.

15. The solar cell assembly of claim 14, wherein said first edge is sealed to said first elongated solar cell and said second edge is sealed to said second elongated solar cell by an electrically conductive glue or ink.

16. The solar cell assembly of claim 14, wherein said first edge is sealed to said first elongated solar cell and said second edge is sealed to said second elongated solar cell by a transparent insulator.

17. The solar cell assembly of claim 16, wherein said transparent insulator is ethyl vinyl acetate or spray Teflon.

18. The solar cell assembly of claim 1, wherein a cross-sectional shape of the internal reflector is four-sided and wherein a side of said four-sided cross-sectional shape is the involute of the cross-sectional shape of the first elongated solar cell or the second elongated solar cell.