selfmade homemade DIY supercap ultracap bcap boostcap

[hartiberlin]

Well,
you can build yourself pretty cheaply supercaps yourself.

Just use aluminium foil as one layer and put a little wet only papertowel with saltwater
over it and then use graphite powder on the wet paper towel and then pack as the top layer
a plastic wrap sheet plastic foil (the type from the supermarket).
Then roll these stacked layers up and use a graphite pencil mine from a pencil to make contact to
the graphite powder layer.
The other electrode is the alufoil.

Use a power supply not more than 2.5 Volts to charge up this selfmade supercap.
The graphite pencil electrode is the positive pole
and the alufoil the negative pole.

So you need to hook up the positive output from the power supply to the
graphite electrode and the negative pole from the power supply to the alufoil.

Depending on how large you make the surface area of these sandwiched layers you
will get a few Farads worth of great capacity.

You could also just use only 2 graphite layers, but then the voltage and capacity is lower.

Then don´t charge it up over 2.7  Volts as then electrolysis will happen which will destroy
the alufoil and could produce hydroxy gases.

Then you can measure with a load resistor the capacity of this selfmade supercap
by watching, when it will have discharged to the timeconstant RC voltage level = 0,368 % of the full voltage
tau=RC  => C= tau/R

So for example if you charged up this selfmade supercap to 2.5 Volts and hook
up a 100 Ohm load resistor, watch ( count the seconds) , when the voltage will have decreased to
2.5 Volts *  0,368 = 0.92 Volts and use this time in seconds to calculate the capacity C.

In this example, if the time it took to discharge from 2.5 Volts to 0.92 Volts was 200 seconds,
the  capacity would be:
C= 200 seconds / 100 Ohm= 2 Farad.



Also red and yellow LEDs could be directly powered by such a DIY supercap.

Have fun and post a few pictures of your selfmade supercap.

P.S. Charcoal is not very conductive, but you could also try it with it.
But better use the method posted over here to make your own real
highly conductive graphite powder from a real coal briquet.

See here:
http://www.overunity.com/index.php?topic=790

[RAF]

Again I’m not sure if this is rude or not,

as I understand, The super caps use activated carbon.
I thought of trying this as well ,,,,, “out side the house”
activated carbon has more surface area than carbon and
can be bought at most hardware stores in the form of
drinking water filters. It will need a good crushing,
maybe some screening to get a consistent grit size.
Oh Ya you can get this at the fish store too.

Just a thought

Al

[onthecuttingedge2005]

I am conducting an experiment right now in making high density carbon capacitors using burnt bread, the bread remains porous as it is being toasted into a peace of black carbon with ultra high surface area.

I will test the conductivity first, if it pans out I will see about fixing some aluminum foil contacts for terminals.

if the experiment is successful then I will proceed to assemble a Shewbread capacitor pile and test capacitance.

Jerry

[onthecuttingedge2005]

after a kitchen full of smoke from toasting the shewbread to a pitch black peace of carbon the conductivity test is successful.

the peace of burnt toast measures 1/4 inch in thickness and measures 23M ohms in resistance from backside to front side. this is a good sign.

it will help if a flat weight is placed on the shewbread while toasting to prevent deformity of the bread so that the bread remains flat.

after the thanksgiving festival I will assemble the Ultra cap pile to test for capacitance.

happy thanksgiving to all.
Jerry

[onthecuttingedge2005]

the plan