A fuel cell is a device that converts the chemical energy of a fuel (hydrogen, natural gas, methanol, gasoline, etc.) and an oxidant (air or oxygen) into electricity. In principle, a fuel cell operates like a battery. Unlike a battery however, a fuel cell does not run down or require recharging. It will produce electricity and heat as long as fuel and an oxidizer are supplied.

Both batteries and fuel cells are electrochemical devices. As such, both have a positively charged anode, a negatively charged cathode and an ion-conducting material called an electrolyte. Fuel cells are classified by their electrolyte material. Electrochemical devices generate electricity without combustion of the fuel and oxidizer, as opposed to what occurs with traditional methods of electricity generation.

Fuel cell construction generally consists of a fuel electrode (anode) and an oxidant electrode (cathode) separated by an ion-conducting membrane. Oxygen passes over one electrode, and hydrogen over the other, generating electricity, water and heat. Fuel cells chemically combine the molecules of a fuel and oxidizer without burning or having to dispense with the inefficiencies and pollution of traditional combustion.

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Fuel cells generate electricity from a simple electrochemical reaction in which an oxidizer, typically oxygen from air, and a fuel, typically hydrogen, combine to form a product, which is water for the typical fuel cell. Oxygen (air) continuously passes over the cathode and hydrogen passes over the anode to generate electricity, by-product heat and water. The fuel cell itself has no moving parts – making it a quiet and reliable source of power.
The electrolyte that separates the anode and cathode is an ion-conducting material. At the anode, hydrogen and its electrons are separated so that the hydrogen ions (protons) pass through the electrolyte while the electrons pass through an external electrical circuit as a Direct Current (DC) that can power useful devices. The hydrogen ions combine with the oxygen at the cathode and are recombined with the electrons to form water. The reactions are shown below.

Anode Reaction: 2H2 => 4H+ + 4e-
Cathode Reaction: O2 + 4H+ + 4e- => 2H2O
Overall Cell Reaction: 2H2 + O2 => 2H2O

Individual fuel cells can then be combined into a fuel cell "stack." The number of fuel cells in the stack determines the total voltage, and the surface area of each cell determines the total current. Multiplying the voltage by the current will yield the total electrical power generated.

Power (Watts) = Voltage (Volts) X Current (Amps)

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StemCellHealth, you've got the right definition of "fuel cell", but the jokers at "Hydrogen Hybrid Corp" do not. What they are selling is a water electrolysis cell that makes modest amounts of of H2 and O2 to feed into a standard internal combustion engine, where it displaces some of the fuel/air mixture, resulting in a reduction of power and a modest improvement in fuel economy.

"Hydrogen Hybrid Corp" calls their electrolysis unit a "fuel cell" for marketing reasons only.

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Well...at least you asked a technical question...which I give you thumbs up for. The rest here are just trolling morons who can't say anything positive at all.

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Physical chemistry was a long time ago for me, but I figured 2500 L of H2 at STP would require electrolysing about 2 1/4 L of water. No idea how much electricity it would require at say, 50% efficiency...

Of note, in a 14L engine running at 1000rpm (at 100% VE), that gives you an air:H2 ratio of about 25:1

Hey, if it can reduce soot and NOx and is cheaper than particulate filters, then it's worth doing...

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The introduction of hydrogen allows the diesel engine to more efficiently burn the diesel. Thats how it works. Hydrogen changes the "burn time" of the atomized diesel allowing the fuel mixture to more fully combust during the power stroke.

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Yep. But if they revealed that the rather modest improvement in fuel economy is accompanied by a reduction in power and performance, they wouldn't sell any.

So, for marketing sake, they use a lot of bafflegab and wildly exaggerate their claims.

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Well said. I've not seen a more closed-minded bunch of self-destructive types in a while like I have here.

Thank God for people who at least try and be innovative...even if it fails. Where would all these whiny little children be if they didn't have all their toys thanks for people who took risks and didn't listen to the same counterparts of the doomsayers here well over 100-200 years ago?

I bet alot of people here believe in God too....say it ain't so.

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Tim, you've waaay oversimplified it. A steam engine is more than just "boiling water", making it requires a basic understanding of physics and engineering (and a lot of steel). Making a steel ship requires an understanding of the principles of buoyancy. Building a flying machine requires an understanding aerodynamics, as well as the physics of the engine powering it. Flying to the moon requires a detailed understanding of physics, chemistry, metallurgy, biology, and celestial mechanics. Making a digital computer requires knowlege of electronics, physics, chemistry, and advanced mathmatics, (and a lot of processing of that "beach sand").

In short, all those things you mentioned requires a full understanding of the principles involved, and not one of them involves violating the basic principles and rules governing how the universe works.

Understanding some of the physics involved, I realized that the rather modest improvements in fuel economy with these "HHO" devices are accompanied by a reduction in power and performance. It would be cheaper to go light on the accelerator, and it would be more efficient to simply use a smaller engine.

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Chris,

You seem to believe that we scientists know everything about the physical "laws" and that there is nothing left to be discovered whereas I do NOT! I guess we don’t need that giant supercollider.

There are MANY questions left unanswered and without an open mind about new ideas we will NEVER have the answers. By the way, NONE of the inventors had a "FULL UNDERSTANDING" of physics when they invented these miracles. BUT THEY DID HAVE DREAMS AND VISION.

They may be right and they may be wrong, but I am AT LEAST willing to LISTEN and give them the benefit of the doubt (not money) until they can prove themselves.

Yes, I know. Not blindly believing in dogma is heresy. I guess that I’m guilty as charged. I'd rather follow Christopher Columbus than the Catholic Church.

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While I appreciate and share your optimism (for example I am a strong supporter of the human exploration and settlement of other worlds, especially Mars), I have to respond to this:

"I'd rather follow Christopher Columbus than the Catholic Church."

This extends the usual myth that conventional opinion in Columbus' time held that the Earth was flat by roping in the Church, claiming the Church to hold this belief.

Both are false. Educated people knew perfectly well that the Earth was a sphere. Columbus' difficulty in securing funding arose from disagreements over the Earth's circumference; he miscalculated it as being much smaller than it really is, whereas established opinion, citing remarkably accurate measurements going back to classical antiquity, understood the circumference to be about what it really is. As they correctly argued, given the vast distance involved, Columbus could never have reached Asia with the limited range of his caravels, even without the Americas in his way, which none of them was aware of.

Some of Colmubs' uneducated sailors may well have feared sailing over the edge of the world, but that's a separate issue.

In any event, the Catholic Church and religious belief never entered into the discussion. Even during the Galileo controversy, when it did become enmeshed in an astronomical dispute, the Church never held that the Earth was flat; its spherical shape was assumed by all parties.

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Tim, every one of those things you mentioned only happened after all the basic principles were researched and understood. Improvements on those things only happened after additional research refined the knowlege of those principles.

No, I've never assumed that we knew everything, quite the contrary. But history has shown repeatedly that basic research and understanding fundamental principles always comes first. You're assuming we should just dream big and make things happen without understanding what we are doing, and that rarely works.

Christopher Columbus was lucky. If North America and the Caribbean islands hadn't been where he thought Asia was, he and his crew would likely have perished in the middle of the ocean.

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Won't work, as it would take 14 times the total power output of the engine to run such a big honkin' watt sucking electrolysis cell. Thats why units like this supply only a small amount of the fuel needed.

Of course, if you think you can do the impossible, you are free to try!

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