Photovoltaic device using low iron high transmission glass with antimony and reduced alkali content and corresponding method
A high transmission low iron glass includes antimony, has reduced total alkali content, and increased silica content, and is suitable for use in photovoltaic devices (e.g., solar cells) or the like. A method of making the glass is also provided. In certain example embodiments, the glass composition may be made on a pattern line with a highly positive batch redox.
1 . A photovoltaic device comprising:
a patterned glass substrate, wherein at least one surface of the patterned glass substrate has an average 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
73-76%
Na 2 O
10-20%
CaO
5-15%
MgO
0-3%
K 2 O
0-2%
total iron (expressed as Fe 2 O 3 )
0.01 to 0.03%
FeO
0 to 0.0015%
cerium oxide
0 to 0.07%
antimony oxide
0.1 to 0.4%
SO 3
0.1 to 0.6%
wherein total alkali content (Na 2 O+CaO+MgO+K 2 O) of the glass substrate is no greater than 24.35%, the glass substrate has a density of no greater than 2.495 g/cm3 and a glass redox of no greater than 0.12, and wherein the glass substrate has a total solar transmission (ISO 9090 1.5 AM) 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.
2 . The photovoltaic device of claim 1 , wherein the glass substrate has a total alkali content of no greater than 24.25%, and comprises:
total iron (expressed as Fe 2 O 3 )
0.01 to 0.025%
cerium oxide
0 to 0.03%
antimony oxide
0.15 to 0.30%.
3 . The photovoltaic device of claim 1 , wherein the glass substrate comprises:
total iron (expressed as Fe 2 O 3 )
0.01 to 0.025%
cerium oxide
0%
antimony oxide
0.18 to 0.28%.
4 . The photovoltaic device of claim 1 , wherein the glass substrate has a total solar (τe) transmission of at least 91.5%, and a density of no greater than 2.490 g/cm3.
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 glass redox value (FeO/Fe 2 O 3 ) no greater than 0.08.
7 . The photovoltaic device of claim 1 , wherein the glass substrate comprises from 0 to 0.0005% FeO.
8 . 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, cerium oxide and selenium.
9 . The photovoltaic device of claim 1 , wherein the glass substrate is substantially free of each of erbium oxide, nickel oxide, cerium oxide, cobalt oxide, neodymium oxide, zirconium oxide, zinc oxide and selenium.
10 . The photovoltaic device of claim 1 , wherein the glass substrate is substantially free of erbium oxide, cerium oxide, and nickel oxide.
11 . 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.
12 . The photovoltaic device of claim 1 , wherein the glass substrate comprises from 0.15 to 0.30% antimony oxide.
13 . 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.
14 . The photovoltaic device of claim 1 , wherein the composition of the glass substrate includes at least twice as much antimony oxide as total iron oxide, by weight.
15 . Glass comprising:
Ingredient
wt. %
SiO 2
73-76%
Na 2 O
10-20%
CaO
5-15%
MgO
0-3%
K 2 O
0-2%
total iron (expressed as Fe 2 O 3 )
0.01 to 0.03%
FeO
0 to 0.0015%
cerium oxide
0 to 0.07%
antimony oxide
0.1 to 0.4%
SO 3
0.1 to 0.6%
wherein total alkali content (Na 2 O+CaO+MgO+K 2 O) of the glass is no greater than 24.35%, the glass has a density of no greater than 2.495 g/cm3, the glass has a glass redox of no greater than 0.12, and wherein the glass has a total solar transmission (ISO 9090 1.5 AM) of at least 90%.
16 . The glass of claim 15 , wherein the glass has a density of no greater than 2.490 g/cm3.
17 . The glass of claim 15 , wherein the glass has a density of no greater than 2.485 g/cm3.
18 . The glass of claim 15 , wherein the glass has total alkali content (Na 2 O+CaO+MgO+K 2 O) of no greater than 24.25%.
19 . The glass of claim 15 , wherein the glass has total alkali content (Na 2 O+CaO+MgO+K 2 O) of no greater than 24.0%.
20 . The glass of claim 15 , wherein the glass comprises:
total iron (expressed as Fe 2 O 3 )
0.01 to 0.025%
cerium oxide
0 to 0.03%
antimony oxide
0.15 to 0.30%.
21 . The glass of claim 15 , wherein the glass has a total solar (τe) transmission of at least 91.5%.
22 . The glass of claim 15 , wherein the glass is substantially free of each of erbium oxide, nickel oxide, cerium oxide, cobalt oxide, zirconium oxide, zinc oxide, neodymium oxide, and selenium.
23 . The glass of claim 15 , wherein the glass is substantially free of erbium oxide, cerium oxide, zirconium oxide, zinc oxide, and nickel oxide.
24 . A method of making patterned glass, the method comprising:
providing a molten glass batch in a furnace or melter comprising from 73-76% SiO 2 , from about 0.01 to 0.03% total iron, and antimony oxide;
causing a batch redox of from about +12 to +52 to occur in the furnace or melter with respect to the glass batch;
forwarding a glass ribbon from the furnace or melter to a nip between first and second rollers, at least one of the rollers having patter defined in a surface thereof, wherein the glass ribbon reaches the nip at a temperature of from about 1,900 to 2,400 degrees F.;
at the nip, transferring the pattern from the roller(s) to the glass ribbon;
the glass ribbon being at a temperature of from about 1,100 to 1,600 degrees F. upon exiting the nip;
annealing the glass ribbon at least after the ribbon exits the nip, thereby providing a patterned glass having a total solar transmission of at least 91%, from about 0.01 to 0.03% total iron, and from about 0.1 to 0.4% antimony oxide.