Solar cell low iron patterned glass and method of making same
View Patent ↗A patterned glass substrate is provided for use in a solar cell. The glass substrate is both patterned on at least one surface thereof and has a low iron content. The combination of low iron content, optional oxidizing agent, and the patterning of the glass substrate results in a substrate with high visible transmission and excellent light refracting characteristics.
1. A photovoltaic device comprising:
a patterned glass substrate, wherein at least one surface of the patterned glass substrate has a surface roughness of from about 0.1 to 1.5 μm;
first and second conductive layers with at least a photoelectric film provided therebetween;
wherein the glass substrate is of a composition comprising:
Ingredient
wt. %
SiO 2
67-75%
Na 2 O
10-20%
CaO
5-15%
total iron (expressed as Fe 2 O 3 )
0.001 to 0.06%
cerium oxide
0 to 0.30%
wherein the glass substrate has visible transmission of at least 90%, a transmissive a* color value of −1.0 to +1.0 and a transmissive b* color value of from 0 to +1.5, and wherein colorant portion of said composition consists essentially of 0.001 to 0.06% total iron (expressed as Fe 2 O 3 ) and 0 to 0.30% cerium oxide.
2. The photovoltaic device of claim 1 , wherein the glass substrate comprises:
total iron (expressed as Fe 2 O 3 )
0.02 to 0.04%
cerium oxide
0 to 0.07%.
3. The photovoltaic device of claim 1 , wherein the glass substrate comprises:
total iron (expressed as Fe 2 O 3 )
0.01 to 0.03%
cerium oxide
0.01 to 0.07%.
4. The photovoltaic device of claim 1 , wherein the glass substrate has a visible transmission of at least 90%.
5. The photovoltaic device of claim 1 , wherein the glass substrate has a positive b* color value.
6. The photovoltaic device of claim 1 , wherein the glass substrate has a redox value (FeO/Fe 2 O 3 ) no greater than 0.10.
7. The photovoltaic device of claim 1 , wherein the glass substrate has a redox value (FeO/Fe 2 O 3 ) no greater than 0.01.
8. The photovoltaic device of claim 1 , wherein the glass substrate has a total solar and/or total energy value τe of at least 90%.
9. The photovoltaic device of claim 1 , wherein the glass substrate comprises less than or equal to 0.005% FeO.
10. The photovoltaic device of claim 1 , wherein the glass substrate comprises less than or equal to 0.004% FeO.
11. The photovoltaic device of claim 1 , wherein the glass substrate is substantially free of two or more of erbium oxide, nickel oxide, cobalt oxide, neodymium oxide, chromium oxide, and selenium.
12. The photovoltaic device of claim 1 , wherein the glass substrate is substantially free of each of erbium oxide, nickel oxide, cobalt oxide, neodymium oxide, chromium oxide, and selenium.
13. The photovoltaic device of claim 1 , wherein the glass substrate is substantially free of erbium oxide and nickel oxide.
14. The photovoltaic device of claim 1 , wherein at least one surface of the patterned glass substrate is patterned so as to have has a surface roughness of from about 0.5 to 1.5 μm.
15. The photovoltaic device of claim 1 , wherein both surfaces of the glass substrate are patterned.
16. The photovoltaic device of claim 1 , wherein the glass substrate includes no more than 0.07% cerium oxide, more preferably no more than 0.06% cerium oxide.
17. The photovoltaic device of claim 1 , wherein the glass substrate has a transmissive a* color value of −0.5 to +0.5 and a transmissive b* color value of from +0.1 to +1.0.
18. The photovoltaic device of claim 1 , wherein the composition of the glass substrate has a total iron content of from 0.02 to 0.06%.
19. The photovoltaic device of claim 1 , wherein the composition of the glass substrate includes more cerium oxide than total iron oxide.
20. A solar cell comprising:
a glass substrate;
a photoelectric film supported by at least the glass substrate;
wherein the glass substrate is of a composition having a colorant portion consisting essentially of:
Ingredient
wt. %
total iron (expressed as Fe 2 O 3 )
0.01 to 0.06%
cerium oxide
0 to 0.30%
wherein the glass substrate has visible transmission of at least 90%, a transmissive a* color value of −1.0 to +1.0 and a positive transmissive b* color value.