alufoil cell

[hartiberlin]

Now after about 28 hours later the saltmix has dried out and the
opencircuit voltage went down to 1.02 Volts.

Amazingly the voltage was 3 hours before already at 0.8 Volts...
Hmm, so now the last 3 hours it has risen now after midnight again 0.2 Volts
to now 1.02 Volts.

Hmm, strange, maybe we have today a high X-Ray output of the sun
as these cells tend to follow the X-Ray output of the sun.

Regards, Stefan.

[Walter Hofmann]

Hi stefan,
this is the normale reaction because first of all the contact of the all the parts are to loose there should allways be a pressue to ensure a solid contact because due to the drieing process there is a shrinking and this gives a bad contact. especialy the graphit plates need a solid contact.
the other part is that in general the short circuit curent measuring should not last longer as max of 10 seconds followed by a break of at least one minute like allready described in the function of my AGcells this should be up to three times it creates a kind of formating , but if the short circuit last longer as 10 seconds there starts allready a disintegrading process which will stop the regenerating of the voltage and it takes a much longer time to start the regenerating/formating process again.
The concentration of K2Co3 should not be higher as 15% bei a specific gravity of 1.190 gr/ml because everythings above this level wil be contraceptive and shorten the live of the parts.
the proportion of the K2Co3 should be 7TS ( teaspoon) of seasalt to 1TS of Potash (K2Co3) diluted in destilled water and this mixed with the graphitpowder and then put on to the alu foile and then the graphite plate with at best a soldered on leadwire to ensure stable contact and the hole with a bit of pressure put together.
greetings
walt

[hartiberlin]

Hi Walter,
Today the voltage is back to 1.18 Volts  at this cell !
Now the slat and the graphite all has dried out and it is amazing,
that it gained so much voltage again.
Also the graphite plate seems to be pretty cold on the surface as if it
is real metal. Have to see if I can find my old digital temperature meter to see,
if it is colder than the surounding air.

Well, as this is now dried out completly I will now put a 100 Ohm load resistor on
it and report again.

I did it different than you Walter, cause I just put the saltmix first as a small
layer onto the alufoil with no graphite first in there.
Then when the saltmixwas plated as a small layer onto the alufoil,
I then poured in a second step only a small layer of graphite powder
onto the saltlayer, so the graphite is only at the top
and can not touch the alufoil !
This is important to the isolation of the alufoil versus the graphite.

I also just heated the whole cell from above with a 60 Watts
incandescent lamp for half a minute and I was able to raise the
voltage this way from 1.18 Volt to 1.36 Volts !
After taking the light away it has setteled down th 1.15 Volts.

As the voltameter has a innerresistance of 30 KOhm, I now wanted to
see what the inner resistance of the cell is and what current capabilities
it has .
I now connected a 100 Ohm resistor as a load and now in 2 minutes
the voltage on it went down to 0.05 Volts.
SO it seems the cell has a very high inner resistance and is not able
to drive a real load in this dried out state.
It still gives a pretty high voltage with aroun 1.15 Volts opencircuit
( at 30 Kohm load) but with a realworld load such as 100 Ohm
it is not able to drive a current and the voltage breaks in.

So now I will try to rewet it and see, what it wil bring then.

Regards, Stefan.

[hartiberlin]

Ups, after half an hour the cell is now up again to 0.4 Volts at the 100 Ohm
load resistor ! This is at least 4 mA !
I have to see, how this goes on now.
as the saltmix and graphite is very dry now, I wonder how this works...
Hmm...

[hartiberlin]

I wanted to se, how the cell would behave, when I would
heat it up, so if any water would have still remained in the slat crystalls
these would be gone after heating.
So I put this cell with the Alufoil onto the oven
and heated it over 100 degrees Celsius.

While heating it up I watched the open circuit
voltage.
The opencircuit voltage went up from 0.75 Volts at room
temperature to about  1.1 Volts at around 60 to 80 degrees
and then decrease again rapidly until it was near zero volts.
Then I shut off the heatingplate and took the cell away from it.
Now with a 100 Ohm load the cell really showed 0 Volts.
So I seemed to have killed the cell for its function.

Maybe I destroyed the surface layer between the alufoil and
its oxids and chlorids and carbonats at the  surface layer between
the aluminium and the salts.
Or also the other transistion layer between the saltmix and
graphite was killed now.

I have now put again the voltmeter onto the cell
without a load resistor and will see, if the cell
will regain voltage, when it has cooled down.

Regards, Stefan.