Makin fuel cell

[akcapr]

I heard it was possible to make a fuel cell with 2 beakers and a salt bridege, one beaker with dilute acid, one with dilute base, and sometin with bubling o2 and h2 through it and sometin bout electrodes. Does anyone know a little better how i could make one. I thought it would be cool for my Hydrgoen fuel project im doing.

[Guest abcdefg]

Well, in my school we had a hydrogen fuel cell powered car club. We had these little square fuel cells that produced oxygen in one line, and hydrogen in another. If y9ou don't want to buy one of those, then get:

4 D sized batteries

2 stainless steel screws (you DON"t want the to rust)

2 good sized lengths of wire

a glue stick cap

hot glue

 

Bassically, you hook the wires to the screws, and then to the battery terminals. In the glue stick cap, poke a hole on the top and slip it down the wire that is on the negative terminal of the battery. Push it ujnntill it is touching the screw, and glue around the hole you put in it so it is air tigh, and secured to the wire. When you put the screws in distilled water with salt (boil water to distill it) then the hydrogen will collect under the glue stick cap. You can use rubber tubes to collect it in a special container if you want. Or you can just light the hydrogen!!

-Mike

[akcapr]

how will this produce energy or electricity when ur adding it with batteries?

I wanta cell to make electricity like a battery

[akcapr]

i got the idea at this site:

 

http://genchem.chem.wisc.edu/demonstrations/Gen_Chem_Pages/17electropage/electromain.htm

 

but i cant really figure out how it works

[BenSon]

If you want to make a cell similar to a battery then do a search on galvanic cells these are pretty easy to make and interesting too

 

~Scott

[akcapr]

ya but it has to be a fuel cell or it wouldnt make sense for my Hydrogen Fuel project im doing.

[BenSon]

"I wanta cell to make electricity like a battery"

 

Sorry i was a bit confused....

 

~Scott

[akcapr]

surely someone should know how or at least have an idea how. Maybe YT knows.

[akcapr]

any one work for hydrogen research for Ford or Bmw?

[calbiterol]

Description: A fuel cell is made using two half cells. One of the half cells consists of oxygen gas bubbling into dilute acid (cathode), and the other consists of hydrogen gas bubbling into dilute base (anode). Platinum electrodes are used in each solution, and both half cells are connected with a salt bridge. A voltage is taken between the platinum electrodes.

 

If I'm reading the information on your site correctly, ak, then this is what they mean:

One beaker has a diluted acid in it. Oxygen gas is bubbling up through the solution, and there is a platinum electrode in the beaker. This is the cathode. The other beaker has a diluted base in it with bubbling hydrogen. This also has a platinum electrode. This is the anode. The two are connected with a salt bridge, and the voltage is measured on the two platinum electrodes.

 

Like I said, that's if I'm reading it right.

 

[Edit: I kinda doubt that someone who worked in a hydrogen research facility would spill their secrets, but they might give you a simple cell design.]

[Skye]

The problem here is that fuel cell can mean two different things. It can be a cell that uses a fuel to produce electricity, or a cell that uses electricity to produce a fuel.

 

The site described the first process, abcdefg described the second process.

[akcapr]

someones bound to actually know

[Xavier]

The essence of a hydrogen fuel cell that acts as an electrical generator in that a positive charge is passed from one half-cell to another electrically isolated half-cell using chemical energy. This creates a build-up of potential difference between the half-cells that can be tapped by a wire completing the circuit between them.

The simplest (in terms of the chemistry) type of fuel cell makes use of a membrane that is electricaly insulating (electrons cannot pass through) but allows hydrogen ions (protons) through.

 

The oxygen dissolved in a dilute acid will use up some of the abundant protons to spontaneously form water in the presence of platinum or a similar catalyst; not much but enough to slightly reduce the acidity and cause a few more of the molecules of the acid to dissociate than is energetically optimal for the species. Gaining further protons to replace those removed by the oxygen would put this half-cell in a more energetically favourable state.

Meanwhile, more platinum breaks up a few dissolved hydrogen gas in the other half-cell liberating protons which are drawn through the membrane along the chemical potential. In a normal solution the electrons would jump along with the protons and the hydrogen and oxygen would combine slowly (depending on the catalyst, temperature etc) until they are depleted but in a fuel cell the electrons are specifically excluded from moving, except via an external wire.

 

A saltbridge as used in a galvanic cell is not what is needed between the half-cells but replace it with a bridge which conducts protons, not electrons and the rest is easy.

There are a variety of designs of fuel cell that package the positive charge as different ions with suitable ion selective membranes for different combinations of efficiency, throughput and operating temperature and pressure and the actual chemistry is quite odd looking as it requires some rare, energetically very unfavourable species to accumulate, which they will because the energetic 'payoff' of the H2+½O2->H2O reaction is so big.

 

NB the usual membranes are reasonably high-tech polymers but I have heard discussions of the use of kidney cell membranes, which have massively efficient active proton pumps in them. This is an example of Molecular Manufacturing (The pores consist of 2-3 protein molecules that would be individually placed in a self assembled lipid bilayer membrane) that is on the cusp of appearing.

More prosaically, I once read that, at c.1°C the surface layers of ordinary water ice crystals can conduct protons, not electrons! Now, if that could be used in a fuel cell...

 

A topical website:How to make a fuelcell at home!

http://www.guerrilla.net/reference/power_systems/fuelcell/fuelcell.pdf

[akcapr]

i guess its not as easy as i thought. But did you check out that/this site:http://genchem.chem.wisc.edu/demonstrations/Gen_Chem_Pages/17electropage/electromain.htm

 

and di u figure out how they made that one to work?

but if its just as hard as in the link i wont bother trying. Great explanation though

[akcapr]

oh and on the link scroll down a bit to find the fuel cell

[calbiterol]

ak, that's exactly what I was describing above - assuming I got it right. And from what Xavier said, it doesn't sound like what is on that site would work at all.