Bruce?s 2nd cell picture

[hartiberlin]

Hi All,
here is Bruce?s second cell I got from him already a bit
"hacked" and reassembled with fresh wetted graphite
powder inside.
This cell now gives open circuit about 1 Volt and
under 50 Ohm load also begins at around 0.65 Volt and then slowly
goes down to around 0.5 Volts.
This is still much bigger in size as the TicTac box,
so the TicTac box cell is better in power/weight
relationship !
It seems to be much better to use graphite plates instead of
graphite cylinders.

Regards, Stefan.

[Bruce A. Perreault]

Stefan,

This is not a fair comparision. My cells generate 1.8 volts and hold a load. As you have witnessed, the only reason why my cells that I sent to you are not generating the current that is expected of them is because they dried out sitting in customs and more importantly the anode contact got corroded because I used the wrong contact alloy. This problem is now fixed in my new design. So please sit tight.

? ? ? ? ? ? ? ?-Bruce P.

[hartiberlin]

Hi Bruce,
well they might generate 1.8 Volts at the beginning of their life,
but not later, when the first chemical reaction is used up.

I don?t think, that they will generate all the time 1.8 Volt
opencircuit.
You probably applied some NH3 ammonia to the graphite powder
and as this was used up then the voltage just comes down
to its normal voltage of 1 to 1.3 Volts open circuit.

As I just refreshed the cell only by putting in fresh saltwater,
it did not go up again to 1.8 Volts.
So do you say, when it has dried out once, it will never reach the 1.8 Volts
again ?
I also rmoved the corroded stainless-steel clamp and connected the
graphite cylinder directly to the crococable, so it has good contact
now and wih a 50 Ohm load resistor it just starts now at 0.7 Volts
and then goes down in a few hours to 0.48 Volts.

Well, I guess that is the typical setup for a Zamak-Graphite cell
and any other voltage levels can only be got, if you add some other chemical
substances, like you probably did.
I think this is still a good cell construction, but a bit too expensive
compared with plate designs, which will also much easier scale up.

Regards, Stefan.

[Bruce A. Perreault]

Stefan,

When the cells dried out the graphite cells became clogged with microscopic crystals.
The 1.8 volts can be kept up to this level until the alloy completely decays, which
will be a long time. The current has nothing to do with the few drops of ammonia
that is added to the one gallon of water. It is used only to adjust the pH.

                           -Bruce P.

[hartiberlin]

Bruce,
when the alloy is oxidized, the 1.8 Volts will never be reached again.
Then you will only get about 1.1 to 1.3 Volts Maximum...
The gray layer of the oxidized Zamak is paying its tribute,
so the voltage will always be lower then.

Regards, Stefan.