Hi All,
did anyone of you already try to make solar cells from
using Alufoil as the back electrode ?
I am looking for a really cheap method how to do
a selfmade homemade solar cell, that everyone can make
at home and can at least achieve 1 to 5 % efficiency
but with really cheap materials, like
Alufoil, Titandioxid, Graphite and a cheap electrolyte
like in a Graetzel cell.
The question still is, what to use as the front transparent conductive
electrode layer ?
Has anyone read already the patents from Nanosolar.com, what they
are using as a printable transparent front electrode ?
What are the parameters of the p-n area layer between the different materials
that convert sunlight into electricity.
As I understand it, this layer area must be very thin in the micrometer
or nanometer range for efficient electricity generation.
Maybe one who understands the solar theory can
explain it in simple words how the sun?s photon energy
can transfer electrons in the p-n layer from one
energy potentail layer well to a higher potential and thus
crossing the p-n-layer well barrier.
What dissimular metals could be used to do this
instead of a p-n-layer ?
Also would it be possible just to use some kind
of electroplating some other metals onto alufoil to
achieve this ?
If anybody has worked in this area already, please
post your experience with it.
Imagine being able to build very cheap solar cells
from alufoil you buy cheap at your supermarket
and just paint them with a mix of titandioxid
and graphite and stick a bit of silverwire ontop of it
and thus get for around 1 US$ a 1 x 1 meter cell
which can output 10 Watts in direct sunlight...
Many thanks.
Regards. Stefan.
G'day Stefan,
Please correct me if I'm wrong, but I have always thought that you cannot electroplate aluminium.
Hans von Lieven
Hi Hans,
yes, Aluminiumfoil builds up a small layer of aluminiumoxid ontop of it,
but Aluminiumfoil could be just used with Titandioxid and graphite maybe.
The question is, what donators have to be implemented to get a right
p-n- layer to extract the photon energy or if just dissimular metals
are enough to get a simular bandgap to convert photons into electricity...
What about using maybe heated Weinsteinacid with Fluorescin
which is a phosphorescent and stores light energy.
Maybe this could be used additionally to store the light energy or
has the right band gap interval to convert light energy more efficiently ?
Also all the other phosphorescent salts that glow in the dark,
maybe they can be used to convert light energy to electrical energy
in the right setup ?
What about electroplating steel sheets or copper foils with other
materials ?
Did somebody try this yet ?
What must be the right bandgap distance level to convert sunlight photons most
efficiently to electrical energy ?
Is it just about 0.5 ElectronVolts as it is about in silizium solar cells ?
G'day Stefan
Is this the sort of thing you are looking for?
Us patent application 20060060237 Formation of Solar Cells on Foil Substrates (attached)
alternatively here is another way to make your own solar cells cheaply:
http://www.solideas.com/solrcell/english.html
Greetings
Hans von Lieven
Hi Selvemade Men
This might be interesting:
http://www.youtube.com/watch?v=kLSARSw2JUQ&NR=1
and this one to
http://www.youtube.com/watch?v=gQJiGsMv07Q&mode=related&search=
helmut
G'day again,
Another way to do it with aluminium foil, not so do it yourself this time,but interesting just the same.
http://www.newscientist.com/article.ns?id=dn3380
Hans von Lieven
Does anyone here know about the screenprinting process for making solar cells?In the early 90's I made some copper oxide solar cells that worked.They did not have a lot of power however.I see the screenprint process for making solar cells advertized for sale.But have not run across much in the way of free info on itTriffid
I have made homemade zinc oxide which is conductive like tin oxide.These two oxides carry a current and the tin oxide dries clear.The zinc oxide is a white color and it's used in a lot of paints and pigments.I guess I could make tin oxide too.Just need some tin metal as a starting material.Triffid
I go to a lot of garage sales and try to buy "glow in the dark stuff "when I find it.I have my bathroom set up to trap some light when I get up at night and turn the light on.It takes a few minutes for the glow to subside.I have about 10 "glow in the dark" items setting in my bathroom.It helps me in my free energy work.If I can see it then I can more easily understand it. What I should do with electricity, heat,magnetizm,etc.Triffid
I have found the process for making solar cells by using aluminum foil as the backside(pos side).If I can get the number of the japanese patent for screen printing solar cells(1996) I should have the whole process.The answer was in another thread here.I still need that patent number.Triffid
@Triffid,
try one of these patent numbers:
5928438
5726065
Hope that helps,
Mark
http://www.google.com/patents?q=5928438
http://www.google.com/patents?q=5726065
I tried yeasterday to build an
alufoil solar cell on the basis of a Graetzel cell.
I tried it this way.
I scratched the alufoil with sandpaper a bit,
but my alufoil was too thin, so I used directly
the alufoil from the box , so there is always a
small Aluminiumoxid layer on it.
Then I put ( dissolved) Titandioxid TiO2 into IsoPropylalcohol 98 %
and smeared it in a very thin layer onto the alufoil.
Then I heated up the Alufoil on
the plate of my electro kitchen stove
to get some of the TiO2 into the Al2O3 oxid and
build a PN layer...
Then I use a hibiscus tea in destilled water mixed with table salt solution as the electrolyte onto it
and sprayed that hibiscus tea -tablesalt-solution onto the alufoil with the
Titandioxid.
Then I used some graphite brush to have contact
with the
hibiscus tea table salt solution and
measured the voltage between
the alufoil and the graphite brush.
It was around 0.7 Volts
but there was no light sensivity of this cell.
It was a pure galvanic effect.
So basically I just built only a galvanic battery cell.
Hmm, I have to find out, how I really can build
a PN junction layer with Alufoil and other materials
or I really have to go with a
mix of Indium-TinOxid on glas and TiO2 as the PN-Layer.
The real secret of the Graetzel cell is purely where exactly
the PN- junction is located and I guess it is the very thin layer of
the conducting Indium-Tin-Oxid bounded to the TiO2 layer.
This InZnOxid and TiO2 forms the PN junction which is
sensitive for the light and the Jodid electrolyte is only
for the current conduction and can also be replaced by other
electrolytes..
Okay, so how do I now make my own cheap
conducting Indium-Tin-Oxid glas plates ?
Or does anybody have an idea to still use the Alufoil
for the backplate of a solar cell ?
Many thanks.
Regards, Stefan.
I went ahead and made hard copies of patents 5928438 and 5726065.I will take them home tonight and see if I have a match with the info I already have.As far as I understand the process the aluminum foil is on the bottom and acts as the pos electrode.Then something is put on the foil,allowed to dry then baked at 600 degrees F for 3 to 5 minutes.Once cooled down something else is put on top ,allowed to dry ,then baked at 600 degrees F for 3 to 5 minutes.Then last a metal paste is placed on top and allowed to dry,but no baking! This top layer then acts as the neg electrode of the cell.An outdoor grill is mentioned in the article as a good way to achieve these temps.Thanks to those of you who helped with the numbers.Triffid
I should add that that last layer(metal paste) is put down in a screen pattern,not as a solid layer.Triffid
Hi triffid
please post the process as exact as you can.
Is it all in these patents or are these different papers ?
The main problem is how to get a large PN-surface-layer which is
exactly sensitiv for sunlight.
What must the bandgap be in ElectronVolt to be sensitive
for sunlight ?
The easiest thing would be to come up with a kind of "ink"
that you just put on alufoil and which will harden to your alufoil and
also acts as the second electrode.
So maybe a mix from Titandioxid and graphite and a special
color ink like Fluorescin will do it ?
The problem is, that all commercial cells have these
ITO conductive Indium-Tin-oxid layers, which make
these cells expensive and hard to replicate at home.
So we have to find a way to not use these ITO coated glasses...
One way of doing it could be, to put the alufoil with a PN-layer-coating
into transparent conductive saltwater and let the sun shine through it.
Then you could use a graphite rod inside the saltwater to act as the other
electrode.
Okay, this cell would be bulkier due to the use of the saltwater,
but anyway, if you could this way get rid of the ITO coated glas,
why not...
There must be a simple solution to this question !
We just have to find it.
Maybe one could also just electroplate the alufoil
with Titandioxid or use High Voltage DC to put the
Titandioxid into the alufoil.
There must be just build a bandgap-layer between the
alufoil and the "bondage" layer, which is sensitive to the sunlight
in the right electronvolt range.
That is all we have to find.
As bounding graphite particles directly onto alufoil
that already gives a bandgap voltage of about 0.7 Volts,
but it is not sensitive to sunlight and is more likely a galvanic cell
with the air moisture
which consumes the alufoil.
Regards, Stefan.
Here are the links to the 2 patents user triffid
mentioned:
http://v3.espacenet.com/espacenetDocument.pdf?KC=A&date=19990727&flavour=trueFull&NR=5928438A&locale=en_EP&CC=US&FT=D
http://v3.espacenet.com/espacenetDocument.pdf?KC=A&date=19980310&flavour=trueFull&NR=5726065A&locale=en_EP&CC=US&FT=D
You have to give in the graphical code to download the full PDF file this way.
But these methods are far too complicated...
An easy method to use silver coating for the pickup electrode is to use
collaidal silver.
If you make a collaidal silver for almost 1 hour from a hot destilled water baker
and afterwards put some stuff into this water,
the silver particles will kling to all stuff
and you get a silver layer.
This could be used to make silver contacts on a solarcell.
This happened to me one time, when I made too long the
collaidal silver in the water baker and all the silver particals
coated onto the inner walls of the glas baker...
Pretty energy efficient method to coat anything with a silver layer...
Regards, Stefan.
Unfortunately I could not match the patents 5928438 and 5726065 to the info I already had.The reason being (?) I need the number to the japanese patent for the japanese website.Not the us patent site.I did relocate the link to the japanese patent website.I also need to stop trying to do stuff from memory.There is another layer in those directions I gave that you put on and let dry /then bake for 3 to 5 minutes.The final layer consists of nickel metal ink that you let dry in a screen pattern(no baking).The final layer acts
as the neg electrode.So to recap :
5)final layer(nickel metal ink in screen pattern)dry/no baking/neg electrode
4)layer /dry/bake
3)layer/dry/bake
2)layer/dry/bake
1)aluminum foil/pos electrode.
So layers 2,3,4 I do not know what they are.Baking times and temps are the same for all layers that need baking.I am so close to solving this that I can taste it.Triffid
The patent for making solar cells from the screen printing method is US patent #5,538,903.There is link in another thread to a pdf article that r8rchris so generously supplied that tell how to construct these cells using aluminum foil and a different order of layers than if you just start with glass.You can do a search for all the posts by r8rchris(he is a newbe) .
Triffid
Hi1
The pdf file patent is here:
http://www.pat2pdf.org/patents/pat5538903.pdf
Jesus
Stephan,
What is the hybiscus tea for?
Is it a coloring agent? or does it provide some chemical reaction?
BTW, I love your idea on making colloidal silver to make silver electrodes. Brilliant.
Thank you,
jeanna
This is a great topic. I can remember back in the day there were phase change salts you could just put in a bag in the sun. Then Silicon Valley money took over.
Is there a gas that would result in easy ionization. I was reading about ion propulsion and ammonia gas is said to be easily ionizable. As the gas is ionized the electrons go one way in a magnetic field and the ions the other. I just see a bunch of tubes with permanent magnets aluminum and some sunshine. How bought a bottle full of co2 and make sure the infrared gets reflected back to the metal collector plate. This would crete a resonant cavity full of infrared emwave energy.
Ok ,here goes the rest of the info on making a solar cell using aluminum foil
according to patent#5,538,903 and the ebook that r8rchris posted:
5)nickle metal(ink in a screen pattern)-dry only(neg electrode)
4)(n-type)mixed cadium sulphide and cadium chloride and proylene glycol(CdS layer)
3)(p-type)(CdTe layer) an eqi-mol mixture of Cadium (Cd) and Tellurium(Te) powders with addition of CdCl2 and pg(proylene glycol)
2)carbon electrode layer with silver and Indium mixed in.
1)aluminum foil(pos electrode)
layers 2,3, and 4 are to be dried and baked at 600 degree C one layer on top of the other
Triffid
I should add that a propane powered outdoor grill was recommended to bake these cells on.Triffid
Quote from: sparks on October 27, 2008, 04:16:02 PM
... I can remember back in the day there were phase change salts you could just put in a bag in the sun. ...
Sparks,
I take it that you don't remember what these phase change salts were?
jeanna
www.backwoodshomemagazine.com has a lot of practical articles on homemade solar and wind systems.You may have to dig a little for them.Triffid
Sorry,I meant www.backwoodshome.com triffid