MANUFACTURING OF PHOTOVOLTAIC SUBASSEMBLIES

• US 20090255627A1
• Filed: 12/17/2008
• Published: 10/15/2009
• Est. Priority Date: 04/10/2008
• Status: Active Grant

• Current Assignee: Cardinal IG Company (Cardinal Glass Industries Incorporated)
• Original Assignee: Cardinal IG Company (Cardinal Glass Industries Incorporated)
• Inventors: Buchanan, Robert C., Pretorius, Jacobus P. C., Queck, Curtis L., Grommesh, Robert C.
• Granted Patent: US 8,101,039 B2
• Time in Patent Office: Days
• US Class Current: 156/269
• CPC Class Codes: H01L 31/048 Encapsulation of modules
• CPC Class Codes: H01L 31/0488 Double glass encapsulation, e.g. photovoltaic cells arranged between front and rear glass sheets
• CPC Class Codes: H01L 31/073 comprising only AIIBVI compound semiconductors, e.g. CdS/CdTe solar cells
• CPC Class Codes: H01L 31/206 Particular processes or apparatus for continuous treatment of the devices, e.g. roll-to roll processes, multi-chamber deposition
• CPC Class Codes: Y02E 10/543 Solar cells from Group II-VI materials
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 156/1062 Prior to assembly
• CPC Class Codes: Y10T 156/1084 of continuous or running length bonded web
• CPC Class Codes: Y10T 156/1085 One web only
• CPC Class Codes: Y10T 156/125 Plural severing means each acting on a different work piece
• CPC Class Codes: Y10T 156/1309 and securing separate part over hole or aperture
• CPC Class Codes: Y10T 156/1343 Cutting indefinite length web after assembly with discrete article
• CPC Class Codes: Y10T 156/1734 Means bringing articles into association with web

Abstract

Some methods, and corresponding apparatus, for manufacturing photovoltaic subassemblies cause a plurality of desiccant beads to be adhered to an adhesive surface of sheet-like material; the sheet-like material is then, preferably, adhered to an exposed surface of a flexible and electrically non-conductive film, that covers a photovoltaic coating of a first substrate of the subassembly, such that the desiccant beads are held between the sheet-like material and the exposed surface. Some other methods, either alternatively or in addition to the above, include steps for applying the film, that covers the photovoltaic coating, wherein an opening, through the film, is cut, and then aligned, with lead wires of the photovoltaic coating, in the midst of applying the film.

Claims

1. A method for manufacturing a photovoltaic subassembly, the method comprising:

loading a continuous roll of flexible and non-electrically conductive film into a work station such that a first terminal edge of the film, which defines a width thereof, is pulled away from the roll and extends between a first elevation and a second elevation at a first position;

moving a first edge of a photovoltaic coating into proximity with the first position, such that the first terminal edge is approximately aligned with the first edge of the coating, for contact therewith, the photovoltaic coating being adhered to a central region of a major surface of a first substrate, the first substrate extending from the first elevation to the second elevation, and the first edge of the coating extending between the first and second elevations;

moving, in a generally horizontal direction, the first edge of the photovoltaic coating, from the first position to a second position, in order to draw a first portion of the film into adhesive contact with the coating, the first portion extending from the first terminal edge of the film toward the roll;

cutting an opening through a second portion of the film, when the first portion is in adhesive contact with the coating, the second portion extending from the second portion of the film toward the roll;

moving, in the generally horizontal direction, the first edge of the photovoltaic coating, from the second position to a third position, in order to draw the second portion of the film into adhesive contact with the coating, such that the opening in the second portion is approximately aligned with lead wires of the photovoltaic coating;

cutting along the width of the film, to separate a third portion of the film from a remainder of the film on the roll, the third portion extending from the second portion of the film to a second terminal edge of the film; and

moving, in the generally horizontal direction, a second edge of the photovoltaic coating, which is opposite the first edge, into proximity with the first position, in order to draw the third portion of the film into adhesive contact with the coating, such that the second terminal edge of the film is approximately aligned with the second edge of the coating.

2. The method of claim 1, wherein the film includes an adhesive backing that provides the adhesive contact with the coating.

3. The method of claim 1, further comprising adhering a desiccant sheet to an exposed surface of the flexible and non-electrically conductive film, in between the first and second terminal edges thereof, after drawing the third portion of the film into adhesive contact with the coating.

4. The method of claim 3, further comprising forming the desiccant sheet by adhering a plurality of desiccant beads to an adhesive surface of a sheet-like material;

and wherein adhering the desiccant sheet is accomplished by bringing the adhesive surface of the sheet-like material, with the plurality of desiccant beads adhered thereto, into adhesive contact with the exposed surface of the film.

5. The method of claim 3, further comprising applying a spacer member only to a peripheral region of the major surface of the first substrate, after adhering the desiccant sheet, the spacer member for joining a second substrate to the first substrate, in spaced relation thereto;

and wherein the peripheral region surrounds a perimeter of the central region of the major surface.

6. The method of claim 1, further comprising applying a spacer member only to a peripheral region of the major surface of the first substrate, after drawing the third portion of the film into adhesive contact with the coating, the spacer member for joining a second substrate to the first substrate, in spaced relation thereto;

and wherein the peripheral region surrounds a perimeter of the central region of the major surface.

7. The method of claim 6, further comprising:

aligning a peripheral region of the second substrate with the peripheral region of the first substrate, the peripheral region of the second substrate surrounding a perimeter of a central region of a major surface of the second substrate; and

pressing the first and second substrates together, with the spacer member sandwiched therebetween, to join the second substrate to the first substrate, such that the central regions of the major surfaces of the first and second substrates face one another and an airspace is maintained therebetween.

8. The method of claim 7, further comprising forming an opening through the second substrate, prior to pressing the first and second substrates together.

9. The method of claim 7, further comprising applying an adhesive member into an outer perimeter channel, after pressing the first and second substrates together, the outer perimeter channel being external to the spacer member and extending between the peripheral regions of the first and second substrates.

10. The method of claim 1, further comprising attaching the lead wires of the photovoltaic coating to a lead, after drawing the third portion of the film into adhesive contact with the coating.

11. A method for manufacturing a photovoltaic subassembly, the method comprising:

adhering a flexible and non-electrically conductive film to a photovoltaic coating so as to cover a significant surface area of the coating, the coating being adhered to a central region of a major surface of a first substrate, and a perimeter of the central region being surrounded by a peripheral region of the major surface;

adhering a plurality of desiccant beads to an adhesive surface of a section of sheet-like material; and

adhering the adhesive surface of the section of sheet-like material, which has the desiccant beads adhered thereto, to an exposed surface of the adhered film, such that the adhesive surface faces the exposed surface of the film and the plurality of desiccant beads are held between the section of sheet-like material and the exposed surface of the film.

12. The method of claim 11, further comprising forming an opening in film in the midst of adhering the film to the photovoltaic coating, and wherein the opening is aligned with lead wires of the photovoltaic coating, when the film is adhered.

13. The method of claim 12, further comprising attaching the lead wires of the photovoltaic coating to a lead, after adhering the adhesive surface of the section of sheet-like material.

14. The method of claim 11, further comprising:

drawing the section of sheet-like material from a continuous roll of sheet-like material such that the adhesive surface thereof comes face-to-face with a plurality of deflectors; and

wherein adhering the plurality of desiccant beads comprises allowing the plurality of desiccant beads to fall over the deflectors and ricochet therefrom to bombard the adhesive surface.

15. The method of claim 11, wherein adhering the plurality of desiccant beads comprises bombarding, with the plurality of desiccant beads, the adhesive surface of the section of sheet-like material.

16. The method of claim 11, further comprising shielding a portion of the adhesive surface of the sheet-like material, while adhering the plurality of desiccant beads, to prevent any of the plurality of desiccant beads from adhering to the portion.

17. The method of claim 11, further comprising applying a spacer member only to the peripheral region of the major surface of the first substrate, after adhering the adhesive surface of the sheet-like material, the spacer member for joining a second substrate to the first substrate, in spaced relation thereto.

18. The method of claim 17, further comprising:

aligning a peripheral region of the second substrate with the peripheral region of the first substrate, the peripheral region of the second substrate surrounding a perimeter of a central region of a major surface of the second substrate; and

pressing the first and second substrates together, with the spacer member sandwiched therebetween, to join the second substrate to the first substrate, such that the central regions of the major surfaces of the first and second substrates face one another and an airspace is maintained therebetween.

19. The method of claim 18, further comprising forming an opening through the second substrate, prior to pressing the first and second substrates together.

20. The method of claim 18, further comprising applying an adhesive member into an outer perimeter channel, after pressing the first and second substrates together, the outer perimeter channel being external to the spacer member and extending between the peripheral regions of the first and second substrates.

34. The method of claim 11, further comprising:

drawing the section of sheet-like material from a continuous roll of sheet-like material such that the adhesive surface thereof comes into contact with, and spans, a pair of spaced-apart struts of a rotating framework; and

wherein adhering the plurality of desiccant beads comprises allowing the plurality of desiccant beads to bombard the adhesive surface of the section between the spaced-apart struts.

21. A method for incorporating desiccant into each of a plurality of assemblies, each assembly including a first substrate having a major surface, the major surface including a central region over which a photovoltaic coating extends, and a peripheral region surrounding a perimeter of the photovoltaic coating, the method comprising:

allowing a plurality of desiccant beads to fall over a plurality of deflectors, the plurality of deflectors being arranged such that the falling beads ricochet laterally therefrom;

positioning an adhesive surface of sections of sheet-like material face-to-face with the deflectors, while the desiccant beads are falling, such that the ricocheting desiccant beads bombard the adhesive surfaces and adhere thereto;

adhering each of the sections of the sheet-like material, to which the desiccant beads are adhered, to a corresponding first substrate, such that the adhered desiccant beads of each section are positioned between the corresponding section of sheet-like material and the photovoltaic coating of the corresponding first substrate;

applying a spacer member only to the peripheral region of the major surface of each of the first substrates, after adhering the corresponding section of sheet-like material;

bringing each of a plurality of second substrates face-to-face with each corresponding first substrate, such that a peripheral region of each second substrate is aligned with the peripheral region of the corresponding first substrate, the peripheral region of each second substrate surrounding a central region thereof, and

joining each second substrate to the corresponding first substrate, by pressing the first and second substrates together, with the corresponding spacer member sandwiched therebetween, such that an airspace is maintained between each pair of first and second substrates.

22. The method of claim 21, further comprising adhering a section of flexible and electrically non-conductive film to each of the first substrates, before adhering the corresponding section of the sheet-like material, such that each section of flexible and electrically non-conductive film extends over a significant portion of the corresponding photovoltaic coating and includes an exposed surface to which the corresponding section of sheet-like material is adhered.

23. The method of claim 22, further comprising forming an opening in each section of film in the midst of adhering the corresponding section of film to the corresponding photovoltaic coating, and wherein each opening is aligned with lead wires of the corresponding photovoltaic coating, when the corresponding section of film is adhered.

24. The method of claim 21, further comprising shielding a portion of each adhesive surface of the sections of sheet-like material, when each section is face-to-face with the deflectors, and while the desiccant beads are falling, in order to prevent any of the ricocheting desiccant beads from adhering to the portion of each adhesive surface.

25. A manufacturing apparatus comprising:

a hopper for holding and dispensing a plurality of desiccant beads;

a plurality of deflectors mounted in proximity to the hopper, the deflectors being arranged to deflect the plurality of desiccant beads that are dispensed by the hopper;

a rotating framework surrounding the plurality of deflectors, the framework including a plurality of spaced apart struts;

a spindle for holding a continuous roll of sheet-like material; and

a mechanism for drawing the sheet-like material from the roll, held by the spindle, and into contact with the rotating framework, such that an adhesive-backed surface of the sheet-like material, in discrete sections, sequentially span a pair of adjacent struts of the plurality of spaced apart struts of the rotating framework;

wherein each discrete section, of the adhesive-backed surface, that spans the pair of adjacent struts is positioned to receive bombardment by the deflected plurality of desiccant beads.

26. The apparatus of claim 25, wherein:

the hopper dispenses the plurality of desiccant beads by allowing the desiccant beads to fall, under the force of gravity; and

the plurality of deflectors are mounted below the hopper.

27. The apparatus of claim 25, further comprising a conduit for re-circulating, back to the hopper, an excess quantity of the plurality of desiccant beads, which are dispensed from the hopper, but that do not adhere to the adhesive backed surfaces.

28. The apparatus of claim 25, further comprising a chamber in which the deflectors and the rotating framework are at least partially enclosed.

29. The apparatus of claim 28, further comprising:

a bin located in proximity to the hopper; and

a conduit extending from the chamber to the bin and being in fluid communication with the chamber and the bin;

wherein the conduit and bin serve for a re-circulation, back to the hopper, of an excess quantity of the plurality of desiccant beads, which are dispensed from the hopper, but that do not adhere to the adhesive backed surfaces.

30. The apparatus of claim 25, wherein the plurality of deflectors are attached to a plate via mounting features of the plate, the mounting features of the plate allowing for a re-arrangement of the deflectors.

31. The apparatus of claim 25, wherein:

the plurality of deflectors are attached to a plate; and

each of the deflectors is formed as a wedge that includes a deflection surface, the deflection surface slanting downward, and away from plate, so as to face each discrete section, of the adhesive-backed surface, that spans the pair of adjacent struts of the surrounding framework.

32. The apparatus of claim 25, wherein the mechanism for drawing the sheet-like material from the roll, held by the spindle, comprises a motor coupled to the rotating framework, the motor serving to rotate the framework.

33. The apparatus of claim 25, wherein:

the mechanism for drawing the sheet-like material from the roll, held by the spindle, comprises a conveyor belt, at least one substrate being carried by the conveyor belt, and a pinch roller;

the sheet-like material is held between the pinch roller and a major surface of the substrate, such that the adhesive-backed surface of the sheet-like material contacts the substrate thereby attaching the sheet-like material to the substrate; and

the conveyor belt and the pinch roller move the substrate and, thus, the sheet-like material attached thereto.

35. An assembly line for manufacturing photovoltaic assemblies, the assembly line comprising:

a first workstation including a film application work head for adhering a flexible and electrically non-conductive film to each of a plurality of photovoltaic coatings, as each coating is conveyed past the film application work head, so as to cover a surface area of each coating, each coating being previously adhered to a central region of a major surface of a corresponding first substrate of a plurality of first substrates;

a second workstation including a desiccant sheet application work head for adhering a sheet-like material, to which a plurality of desiccant beads have been previously adhered, to an exposed surface of the adhered film of each first substrate after each first substrate is conveyed to the second workstation, such that each plurality of desiccant beads is held against the exposed surface of each adhered film by the sheet-like material;

a third workstation for applying a first member of a seal system along an inner portion of a peripheral region of the major surface of each first substrate, each peripheral region surrounding a perimeter of the central region of the corresponding first substrate;

a fourth workstation for pressing a second substrate together with each first substrate, such that the applied first member of the seal system of each first substrate is sandwiched between the peripheral region of each first substrate and a peripheral region of a corresponding second substrate, and an air space is maintained between each pair of first and second substrates; and

a fifth workstation for applying a second member of the seal system into an outer perimeter channel of each pressed together pair of first and second substrates, each outer perimeter channel being external to the corresponding first member of the seal system of each pressed together pair and extending along outer portions of the peripheral regions thereof.

36. The assembly line of claim 35, further comprising a conveyor belt and rollers configured to convey and to hold each of the plurality of first substrates in an upright orientation such that the major surface of each first substrate extends from a first elevation to a second elevation and faces the film application work head and the desiccant sheet application work head, in sequence, when the conveyor belt conveys each first substrate past the work heads, in sequence.

37. The assembly line of claim 35, wherein the third workstation is located downstream of the first and second workstations in the line.

38. The assembly line of claim 35, wherein:

the first workstation further includes a spindle and a continuous roll of the flexible and electrically non-conductive film, the roll of film being mounted on the spindle, the film including an adhesive backing, and the spindle allowing the film to be drawn from the mounted roll; and

the film application work head of the first workstation includes a pinch roller and a cutting tool, the pinch roller for driving each first substrate through the first workstation and thereby both draw the film from the mounted roll and adhere a section of the film to each photovoltaic coating, and the cutting tool for cutting each section of the film from a remainder of the film.

39. The assembly line of claim 38, wherein the first workstation further includes another cutting tool located between the spindle and the film application work head, the other cutting tool for cutting an opening through each section of the film before an entirety of each section is adhered to the corresponding photovoltaic coating.

40. The assembly line of claim 39, wherein:

the other cutting tool of the first workstation includes a pair of blades and a disk, the blades and the disk being mounted opposite one another so that each section of the film is drawn between the blades and the disk;

the disk is adapted to move into contact with each section of the film in order to support each section while the pair of blades cut the opening in each section; and

the pair of blades are adapted to rotate in order to cut each opening about a perimeter of the disk.

41. The assembly line of claim 40, wherein the first workstation further includes a vacuum source connected to the disk so as to hold a cut out portion of the film from each opening.

42. The assembly line of claim 35, wherein:

the second workstation further includes a spindle, a continuous roll of the sheet-like material and a desiccant bead applicator assembly, the roll of sheet-like material being mounted on the spindle, the sheet-like material including an adhesive backing, the spindle allowing for the sheet-like material to be drawn from the mounted roll, and the applicator assembly being located between the spindle and the desiccant sheet application work head and including a rotating framework formed, at least in part, by a plurality of spaced-apart struts; and

one or both of the desiccant sheet application work head and the rotating framework are adapted to draw the sheet-like material from the mounted roll, such that sections of the sheet-like material span adjacent struts of the rotating framework to surround an inner area of the framework with the adhesive backing of each section facing inward toward the inner area; and

the inner area of the rotating framework is adapted to receive a plurality of the pluralities of desiccant beads, such that, as each section spans adjacent struts of the framework, a corresponding plurality of desiccant beads adheres to each section.

43. An assembly line for manufacturing photovoltaic assemblies, the assembly line comprising:

a first workstation including a film application work head, a cutting tool, a spindle, and a continuous roll of a flexible and electrically non-conductive film mounted on the spindle, the film including an adhesive backing and the spindle allowing the film to be drawn from the mounted roll, the film application work head including a pinch roller for driving each of a plurality of first substrates through the first workstation and to, thereby, both draw the film from the mounted roll and to adhere a section of the film to each of a plurality of photovoltaic coatings, so as to cover a surface area of each coating, each coating being previously adhered to a central region of a major surface of a corresponding first substrate of the plurality of first substrates, and the cutting tool being located between the spindle and the film application work head, the cutting tool for cutting an opening through each section of the film before an entirety of each section is adhered to the corresponding photovoltaic coating;

a second workstation for applying a first member of a seal system along an inner portion of a peripheral region of the major surface of each first substrate, each peripheral region surrounding a perimeter of the central region of the corresponding first substrate;

a third workstation for pressing a second substrate together with each first substrate, such that the applied first member of the seal system of each first substrate is sandwiched between the peripheral region of each first substrate and a peripheral region of a corresponding second substrate, and an air space is maintained between each pair of first and second substrates; and

a fourth workstation for applying a second member of the seal system into an outer perimeter channel of each pressed together pair of first and second substrates, each outer perimeter channel being external to the corresponding first member of the seal system of each pressed together pair and extending along outer portions of the peripheral regions thereof.

44. The assembly line of claim 43, wherein the film application work head of the first workstation further includes a cutting tool, the cutting tool of the application work head for cutting each section of the film from a remainder of the film.

45. The assembly line of claim 43, wherein:

the cutting tool of the first workstation includes a pair of blades and a disk, the blades and the disk being mounted opposite one another so that each section of the film is drawn between the blades and the disk;

the disk is adapted to move into contact with each section of the film in order to support each section while the pair of blades cut the opening in each section; and

the pair of blades are adapted to rotate in order to cut each opening about a perimeter of the disk.

46. The assembly line of claim 45, wherein the first workstation further includes a vacuum source connected to the disk so as to hold a cut out portion of the film from each opening.