Perpetual batteries from Vasilescu-Karpen

[lumen]

The heat is necessary when there is no chemical reactions, as it is the only possible source of energy.
Here we have redox potentials but without possibility of chemical reactions. Therefore this prevents a current to flow when we loop the external circuit at the electrodes. Nevertheless there is still a transition time during which current flows until the equalization of the potentials at the electrodes (then the cell is depolarized). This process is supposed to be endothermic and when we break the circuit, the environment heat allows for the re-polarization of the cell by a reverse process. It is what I understand from Karpen's patent and other papers.

Heat is used to generate the potential difference, but does adding heat really change anything?
I was thinking the potential difference is caused by the difference in electron activity of two dissimilar materials at the same temperature.
Whatever the temperature is, the potential difference always exists until it reaches absolute zero where the cell would finally stop working.

I could be wrong about this, but it seems to be more logical since heating the solution (or two solutions) would increase the activity of both materials and the actual difference in activity would not change but would remain near constant over a large temperature range.

[exnihiloest]

Does it help if you stir it?

Regards Dutchy

When I stir it, voltage and current decrease. I think voltage is due to ions concentration around the electrodes, and they are dispersed when one stirs them. It is the contrary of conventional cells where to stir removes the gas bubbles and enhances the functioning.

[exnihiloest]

Heat is used to generate the potential difference, but does adding heat really change anything?
I was thinking the potential difference is caused by the difference in electron activity of two dissimilar materials at the same temperature.
Whatever the temperature is, the potential difference always exists until it reaches absolute zero where the cell would finally stop working.

I could be wrong about this, but it seems to be more logical since heating the solution (or two solutions) would increase the activity of both materials and the actual difference in activity would not change but would remain near constant over a large temperature range.

Interesting question. I keep the idea for a further experiment where I will heat the cell.
In any case, if we suppose a Maxwell demon, to heat the solution should not increase the voltage which depends only on the type of atoms/ions. But it should increase the current because energy is consumed only when a current is drawn and heat is assumed to be the energy source.

Other completely different point: there is a possibility that oxygen from air plays a role (as in Zn/air battery). The system is not closed. So I consider to put the cell in an enclosed box where I will burn oxygen. If voltage changes with CO2 instead of pure air, a Maxwell demon should be dismissed.

[exnihiloest]

Today tests:

1) I put the cell in a container floating above boiling water. No voltage change. When the cell is charged with 100 ohm, the current drops to 0.3v in 1 mn. In my previous test at ambiant temperature, it dropped to 0.21v. The temperature influence is not conclusive.

2) I had screws of the same metal as my previous cathode. I took one and isolated it with paper. I made a cell by winding a copper wire as anode around the screw. Then I impregnated the paper with my NaOH solution. 
The voltage was about 1v which is what I had already by replacing carbon by copper in my previous cell.
When the circuit is charged with 100 ohm, the current drops very quickly then remains constant around 0.16 mA. When the circuit is open again, the voltage increases much more rapidly than with my previous cell. To heat the cells by placing near a soldering iron increases the voltage from 0.16 to 0.21v. Here the effect of temperature is clear.
It is surprising that in this cell with very close electrodes, the current is not more than in the previous cell. The electrolyte resistance seems not to be a problem.

3) More interestingly, I have put the carbon anode A on one side of my electrolyte container, and two identical electrodes K1 and K2 on the other side. When I close the circuit with a resistance from A to K1, the voltage between A and K2 drops also. When I open the circuit, the voltage of K1 and K2 slowly increases. The two cathodes evolve identically in spite only one was used in the circuit.
My conclusion is that the electrolyte is at about the same potential as the cathode, and what is important for the functioning is what happens near the carbon anode. I made the same with 2 carbon anodes and 1 metal cathode, but no special results, i.e the 2 circuits are almost independant, confirming that there is a very big difference in the actions of the cathode and the anode.

[yssuraxu_697]

It seems to clear a bit what this thing is, or what it is related to!

http://home.earthlink.net/~lenyr/varelec.htm
http://home.earthlink.net/~lenyr/borax.htm

"/.../ An interesting N type negative resistance effect that happens only when the tip of a very sharp aluminum electrode is just barely touching the top surface of the solution. This generates a lot of rf noise as the large misty area at the right part of the curve suggests. /.../"