Sceadwian said:
What you're going to end up with is an overly complicated electrochemical capacitor which wastes energy at every conversion stage. Instead of generating electricty from the process of the primary cell, it's being used to directly electrolyse the water and the hydrogen gas generated is being used for a fuel cell to convert it back into electricty? If you can't see the fundamental flaw in that kind of setup no amount of disuasion is going to stop you, but it's your money.
It was not complex. It is a sealed case (old water filter unit from when I moved in this house and I doubled its size and saved the old one), stainless steel, water and a battery. Only one complex chemical (H2O), only one complex element (Stainless steel; if that is an element) and +/- power (I have 12 volts DC batteries all over so that was not so complex).
I was bored.
Bubbles came out after a couple of minutes (I was schocked), lit one and boom. My kids and I thought it was sort of cool (kids were scared/smart and left; they were loud). It draws so little, 4 D cells will run it.. A friend wants to put it in his car. I said OK..
What is the harm in showing one more thing that does not work? But I hear you and understand your point.
But it is low power and does not get hot. I was sure it would get hot and saw that water is not that great a conductor. I talked to a chemist friend and first thing he asked was is it exothermal (sp) and I said what?. He said how hot does it get.
A very low current draw and a fair amount of gas. So my thought, low power for a little gas, will that boost the mileage. I have a condensor in my car, I remove it and lose 40-50 miles per tank. Problem is, the large engine in my car I have no room for this thing. Another friend said put it in my jeep and we can see if it works.
Now this is the point were I say, it did not do what I expected. It did not get hot.. So why not mix a little of its gas in the carb (air filter) and see what happends?
Hey, I was bored over the holiday, built a game show buzzer (I found an old schematic I did for a guy here and said let's make one). The kids and I just wasted a couple more hours tonight with it. I spent time with the kids and most of the questions were educational.. One was "name a Spice girl". And no one got it (I was the game show controller so I could not play).
Also, my friend is a chemist not an EE. He sent me this knowing not to talk his language... Hope he does not mind me posting this one. And he will never wind up here.

I called him to see why this worked.
His comment to that EMAIL.
Water is an interesting compound, because of its structure it is in an interesting natural resonance. Without getting too technical, the electrical charges do not balance on the bonds, so the H=O=H double bonds (not truly double bonds) have to share charges. This is done by the charge resonating through the bonds from one side to the other:
+H-O=H- <--> -H=O-H+
This is because Oxygen is normally a -2 charge and Hydrogen is a +1 charge.
In order to maintain this structure it resonates.
When you place an electrical charge through the water (pure water does not conduct electricity much) electrolytes in the water (salts, acids) conduct electricity and this pulls the bonds apart by attracting the uneven resonance charges. Depending on how strong the electrolytes (salts, acids), temperature, etc.; this influences how much current is needed to break the bonds, each at their repective electrodes. The hydrogens join to form Hydrogen gas. Which is very stable; and the oxygens to form Oxygen gas. The electrodes give the missing charge through electricity to form the stable bonds.
Is that what you wanted to hear? I hope so. Otherwise, I am not sure what you want me to say. I could say it works because God wanted it to work that way, but that doesn't quite explain it.
That is why resonance frequency can influence the power needed to break the bonds. If you can resonate the molecule at its natural frequency it is just like a glass. It resonates itself, stretching the bonds. Thus less electrical energy is needed to break it apart. Which you probably already know.
In the Linnard Griffin process, he uses metal catalysts to lower the energy needed to break the bonds. This is a chemical reaction.
OK, I've babbled enough. Thanks for your help.