Photovoltaic module package

Patent metadata

Field	Value
Publication number	US-10347782-B2
Application number	US-201214236824-A
Country	US
Kind code	B2
Filing date	Aug 6, 2012
Priority date	Aug 4, 2011
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

A silicon wafer-based photovoltaic module is described, which includes a first outer protective layer and a second outer protective layer, wherein both outer protective layers comprise a low- or no-sodium glass or low- or no-alkali compositions. The photovoltaic modules show resistance to water ingress, no or reduced potential-induced sodium ion drift, and reduced potential induced degradation.

First claim

The invention claimed is:

1. A photovoltaic module comprising
a first protective layer comprising a sodium-free and alkali-free glass sheet,
a second protective layer comprising a sodium-free and alkali-free glass sheet,
at least one crystalline silicon photovoltaic structure between the first and second outer protective layers, and
an additional glass layer, wherein:
the composition of the first protective layer comprises SiO 2 , Al 2 O 3 , and B 2 O 3 , and is sodium-free and alkali-free;
the composition of the second protective layer comprises SiO 2 , Al 2 O 3 , and B 2 O 3 , and is sodium-free and alkali-free;
the additional glass layer comprises a Na-based glass and is characterized by a thickness and rigidity exceeding that of the first and second protective layers; and
the additional glass layer is separated from the photovoltaic structure by a selected one of the first and second protective layers; and
the photovoltaic module defines a photovoltaic structure-free zone between the additional glass layer and the selected protective layer.

2. The module of claim 1 , wherein the selected protective layer forms a sodium migration barrier layer between the additional glass layer and the photovoltaic structure.

3. The module of claim 1 , wherein:
the photovoltaic structure comprises an encapsulant sheet spacing the first and second protective layers by 0.25 mm, or less; and
the first and second protective layers exhibit sufficient flexibility for self-weighted, substantially failure-free bending at a bend radius of less than approximately 100 cm.

4. The module of claim 1 , wherein:
the photovoltaic structure comprises an encapsulant sheet spacing the first and second protective layers by 0.25 mm, or less; and
the first and second protective layers exhibit sufficient flexibility to conform to deviations in flatness between the first and second protective layers.

5. The module of claim 1 , wherein the additional glass layer is secured directly to the selected protective layer.

6. The module of claim 1 , wherein the first and second protective layers are less than approximately 100 μm in thickness across a substantial entirety of the photovoltaic module.

7. The module of claim 1 , wherein:
the first and second protective layers are less than approximately 100 μm in thickness across a substantial entirety of the photovoltaic module; and
the additional glass layer has a thickness of greater than 1.5 mm.

8. The module of claim 1 , wherein the photovoltaic module exhibits at least one of:
(i) an insulation resistance value of greater than approximately 4001MΩ·m 2 tested under the IEC 61215 measurement guidelines for wet leakage current;
(ii) less than 10% output power degradation under the IEC 61215 damp heat standard at approximately 2500 hours of 85° C./85% humidity and −1 kV bias stressing;
(iii) less than 10% fill factor degradation under the IEC 61215 damp heat standard at approximately 2500 hours of 85° C./85% humidity and −1 kV bias stressing; and
(iv) less than 10% series resistance increase under the IEC 61215 damp heat standard at approximately 2500 hours of 85° C./85% humidity and −1 kV bias stressing.

9. A photovoltaic module comprising
a first protective layer comprising a sodium-free and alkali-free glass sheet,
a second protective layer comprising a sodium-free and alkali-free glass sheet,
at least one crystalline silicon photovoltaic structure between the first and second outer protective layers,
an encapsulant sheet spacing the first and second protective layers by 0.25 mm, or less and
an additional glass layer, wherein:
the composition of the first protective layer comprises SiO 2 , Al 2 O 3 , and B 2 O 3 , and is sodium-free and alkali-free;
the composition of the second protective layer comprises SiO 2 , Al 2 O 3 , and B 2 O 3 , and is sodium-free and alkali-free;
the first and second protective layers exhibit sufficient flexibility for self-weighted, substantially failure-free bending at a bend radius of less than approximately 100 cm to conform to deviations in flatness between the first and second protective layers;
the additional glass layer comprises a Na-based glass and is characterized by a rigidity exceeding that of the first and second protective layers;
the first and second protective layers are less than approximately 100 μm in thickness across a substantial entirety of the photovoltaic module;
the additional glass layer has a thickness of greater than 1.5 mm;
the additional glass layer is separated from the photovoltaic structure by a selected one of the first and second protective layers to form a sodium migration barrier layer between the additional glass layer and the photovoltaic structure; and
the photovoltaic module defines a photovoltaic structure-free zone between the additional glass layer and the selected protective layer.

10. The module of claim 1 , wherein the module exhibits an insulation resistance value of greater than 4000 MΩ·m 2 tested under the IEC 61215 measurement guidelines for wet leakage current.

11. The module of claim 1 , further comprising an edge seal between the first and second outer protective layers to form a substantially sealed cavity comprising the photovoltaic structure.

12. The module of claim 1 , wherein the first and second protective layers have a B—OH value of from 0.2 mm −1 to 0.9 mm −1 .

13. The module of claim 1 , wherein at least one of the first and second protective layers has an average surface roughness (R a ) of ≤20 Å.

14. The module of claim 1 , wherein at least one of the first and second protective layers has a thickness below 3 mm and a curvature deformation, W, less than 0.5 micrometer/cm 2 , as described by the equation W=D/L 2 , wherein D is the maximum curvature of glass sheet in μm and L is the diagonal length of glass sheet in cm.

15. The module of claim 1 , wherein at least one of the first and second protective layers has a thickness of 1.8 mm or less.

16. The module of claim 1 , wherein at least one of the first and second protective layers has a thickness of 0.5 mm or less.

17. The module of claim 16 , wherein the first and second protective layers are capable of being processed under roll-to-roll conditions.

18. The module of claim 1 , wherein the additional glass layer has a thickness of greater than 1.5 mm.

19. The module of claim 1 , wherein the module exhibits less than 5% output power degradation under the IEC 61215 damp heat standard at approximately 2500 hours of 85° C./85% humidity and −1 kV bias stressing.

20. The module of claim 1 , wherein the module exhibits less than 5% fill factor degradation under the IEC 61215 damp heat standard at approximately 2500 hours of 85° C./85% humidity and −1 kV bias stressing.

21. The module of claim 1 , wherein the module exhibits less than 5% series resistance increase under exposure to approximately 2500 hours of 85° C./85% humidity per the IEC 61215 damp heat standard and −1 kV bias stressing.

22. The module of claim 1 , wherein the first and second protective layers have an average surface roughness (R a ) of ≤20 Å.

23. The module of claim 1 , wherein the first and second protective layers have respective thicknesses below 3 mm and respective curvature deformations, W, less than 0.5 micrometer/cm 2 , as described by the equation W=D/L 2 , wherein D is the maximum curvature of glass sheet in μm and L is the diagonal length of glass sheet in cm.

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Assignees

• Aitken Bruce Gardiner
• Krol Mark Francis
• Webb James Ernest
• Corning Inc

Inventors

• Aitken Bruce Gardiner
• Krol Mark Francis
• Webb James Ernest

Classifications

• C03C3/085

  containing an oxide of a divalent metal · CPC title

• Y02E10/50

  Photovoltaic [PV] energy · CPC title

• H01L31/0488 Primary

  Electricity · mapped topic

• C03C3/091

  containing aluminium · CPC title

• C03C3/087

  containing calcium oxide, e.g. common sheet or container glass · CPC title