Solar cell module

• US 4,235,643 A
• Filed: 06/30/1978
• Issued: 11/25/1980
• Est. Priority Date: 06/30/1978
• Status: Expired due to Term

• Current Assignee: Amoco/Enron Solar Co.
• Original Assignee: Exxon Research and Engineering Company (Exxon Mobil Corporation)
• Inventors: Amick, James A.
• Primary Examiner(s): Weisstuch, Aaron
• Application Number:
  US05/920,691
• Time in Patent Office: 879 Days
• Field of Search: 136/89 PC, 136/89 EP, 136/89 H
• US Class Current: 136/246
• CPC Class Codes: H01L 31/048 Encapsulation of modules
• 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

Abstract

A solar cell module is provided having a plurality of circular solar cells arrayed on a support structure in which at least the land areas between the cells have facets with light reflecting surfaces. An optical cover medium couples the facets and the cells. Importantly the angular relationship of the facet surfaces is such that light impinging thereon will be reflected upwardly into the optical medium and then internally reflected downwardly toward an active cell area thereby effectively increasing the output of the module.

Claims

1. A solar cell module comprising:

a support structure having at least one planar surface adapted to support an array of solar cells;

a plurality of circular solar cells arrayed on said at least one planar surface of said support structure, said cells having top and bottom surfaces;

a light transparent optical medium coupled to said array and support structure;

land areas between said arrayed circular solar cells, said land areas having a plurality of facets with light relfective surfaces, each facet having a predetermined angular relationship with respect to said planar surface of the support and each other so that light impinging on said light relective surfaces is relected upwardly through said optical medium and forms an angle at the opposite top surface of said module which is greater than the critical angle whereby said reflected light is internally reflected downwardly toward said solar cells.

2. The module of claim 1 wherein the optical medium has an index of refraction between 1.3 and 3.0.

3. The module of claim 2 wherein said optical medium is selected from the group consisting of plastics and a combination of plastics and glass.

4. The module of claim 3 wherein the angle between two upwardly angled facets is between 100°

and 130°

.

5. The module of claim 4 wherein the vertical height of said facets is equal to the thickness of said solar cells.

6. The module of claim 4 wherein said facets are substantially coplanar with the top surface of said solar cells.

7. The module of claim 4 wherein said facets comprise a plurality of V-shaped grooves.

8. The module of claim 7 wherein the angle at the vertex of upwardly extending sides of said groove is about 120°

.

9. The module of claim 8 wherein said V-shaped grooves have a trough which extends downwardly a distance no greater than the bottom of said cells.

10. The module of claim 8 wherein said support is an electrically nonconductive plastic material and said cells are mounted on top planar surfaces of said support.

11. The module of claim 10 wherein said optical medium is a combination of plastics and glass.

12. The module of claim 11 wherein said plastic is a silicone rubber encapsulant.

13. The module of claim 8 wherein said support is an electrically nonconductive rigid light transparent material and said solar cells are arrayed on the bottom of said support and bonded thereto.

14. The module of claim 13 wherein said support is glass and wherein said module includes a light transparent silicone rubber encapsulant optical coupling medium between said glass and said cells and said facets.

15. A solar cell module comprising:

a structure adapted for supporting an array of solar cells;

a plurality of solar cells arrayed on said support structure;

land areas between said solar cells arrayed on said support structure;

a light transparent optical medium coupling said land areas and said solar cells, said optical medium having a top surface adapted to be disposed to receive incident solar radiation;

a plurality of facets having light reflective surfaces angularly disposed in said land areas whereby light falling on said reflective surfaces will be upwardly reflected through said optical medium to the top surface of said optical medium and thereafter internally reflected downwardly through said optical medium to said solar cells.

16. In a solar cell module having circular solar cells arrayed on a support structure having planar surfaces for mounting said array of solar cells, said module having a light transparent optical cover medium thereon, the improvement comprising:

a plurality of facets with light reflective surfaces thereon, said facets located at least in the land areas between the circular solar cells, each facet having a predetermined angular relationship with respect to the planar surfaces of the support structure and each other whereby light impinging on said facets will be reflected upwardly into the optical cover medium and then downwardly toward the circular solar cells.

17. The improvement of claim 16 wherein the facets comprise a plurality of V-shaped grooves and the geometry of said grooves is such that incident light normal to the solar cell module and which falls on the land areas between the cells will be reflected from the reflective surfaces of the grooves and which forms an angle at the top surface of the optical medium which is greater than the critical angle.

18. A solar cell module comprising:

a structure adapted for supporting an array of solar cells;

a plurality of solar cells arrayed on said support structure;

land areas between said solar cells arrayed on said support structure;

a light transparent optical medium coupling said land areas and said solar cells, said optical medium having an index of refraction of between 1.3 and 3.0;

a plurality of V-shaped grooves in said land areas having light reflective surfaces, said V-shaped grooves having upwardly extending legs meeting at a point and forming an angle therebetween, said angle being between 110° and

130°

, whereby light falling on said reflective surfaces will be reflected upwardly through said optical medium to the front surface of said module and thereafter internally reflected downwardly to said solar cells.

19. A method of increasing the output current of a given solar cell module having a plurality of circular solar cells arrayed on a support and defining land areas therebetween comprising:

providing a plurality of facets with light reflective surfaces thereon in said land areas, and thereby

upwardly reflecting solar radiation impinging on said land areas into a light transparent optical medium adapted to internally reflect said radiation downwardly through said optical medium toward said solar cells whereby light impinging on said land area is translated to said solar cells thereby increasing the output current of said solar cell module.