Talk:Fuel cell

From Wikipedia, the free encyclopedia

WikiProject Physics This article is within the scope of WikiProject Physics, which collaborates on articles related to physics.
??? This article has not yet received a rating on the assessment scale. [FAQ]
??? This article has not yet received an importance rating within physics.

Help with this template Please rate this article, and then leave comments to explain the ratings and/or to identify its strengths and weaknesses.
WikiProject Environment
Portal		 This environment-related article is part of the Environment WikiProject to improve Wikipedia's coverage of the environment.
The aim is to write neutral and well-referenced articles on environment-related topics, as well as to ensure that environment articles are properly categorized.
See WikiProject Environment and Wikipedia:Contributing FAQ.
B This article has been rated as B-Class on the assessment scale.
WikiProject Energy
Energy Portal
This article is within the scope of WikiProject Energy, which collaborates on articles related to energy.
B This article has been rated as B-Class on the assessment scale.
High This article is on a subject of high importance within energy.

This article has been rated but has no comments. If appropriate, please review the article and leave comments here to identify the strengths and weaknesses of the article and what work it will need.

This is the talk page for discussing improvements to the Fuel cell article.
Article policies
Archives: 1, 2

/Archive 1 /Archive 2

Contents

[edit] Fuel cells vs batteries

"Fuel cells differ from batteries in that they consume reactants, which must be replenished, while batteries store electrical energy chemically in a closed system."

This distinction seems a little weak. Both batteries and fuel cells consume reactants. Most modern batteries cannot be replenished, but archaic ones like gravity cells could (replacing the anode and the electrolyte was routine).

Can someone clarify the distinction?Kurzon 00:10, 21 January 2007 (UTC)


From an intrinsic point of view, fuel cells and batteries are exactly the same: both generate compound by means of a chemical reaction, where the side effect is electricity and heat. But in reality comparing them is almost like comparing apples and oranges. Any weak distinction made, is only arbitrarily come up with a definition for fuel cell Vs battery. Exceptions to the definitions will arise. --Fieraloca 04:00, 7 February 2007 (UTC)

The distinction may be arbitrary, but it is nevertheless important and valuable. All of the reactant in a battery is contained in the cells. If you want to increase capacity(Amp-hours), then you have to increase the size or number of cells. That is expensive. If you want to increase power output(kW), you also have to increase size of number of cells. This is not true with a fuell cell. Capacity is based on how big your reactant tanks are, and they are cheap compared the cost of battery cells. Power output determines the size and number of fuel cell stacks.

Also, storage batteries (not the ones that you throw away) are rechargable. This means that when the terminal voltage is raised above the cell voltage the reactants will chemically transition to their original states. Fuel cells cannot turn their products (water and heat for a H-O fuel cell) back into the original reactants. —The preceding unsigned comment was added by 149.37.200.150 (talk) 14:10, August 23, 2007 (UTC)

[edit] Electro-galvanic fuel cell

Electro-galvanic fuel cells have been used for decades for measuring oxygen concentration in a breathing mixture. Would a short description or a reference to the article / use be appropriate? Especially as to how the concentration of oxygen gives a difference in voltage, which is converted to a displayed oxygen concentration. --Seejyb 20:12, 20 May 2006 (UTC)

They have their own article Electro-galvanic fuel cell--DV8 2XL 20:26, 20 May 2006 (UTC)

[edit] Removed image

Who removed the image from commons ? its a GFDL licensed image from the French wiki. Fuelcell.en.jpg Reg .Mion 05:46, 16 June 2006 (UTC)

[edit] water fuel cell

1989 A so-called water fuel cell is an unrelated claim of a perpetual motion device, which in fact was not claimed to function the way a fuel cell does.

If the water fuel cell has its own article it could be referenced on, it makes people more critical about real inventions and hoaxes, //Enron/Tesla Motors.Mion 16:31, 19 June 2006 (UTC)

Wikipedia's job is not to make people critical of hoaxes. This belongs in the disambig page, which is why it was removed. Chris Cunningham 17:36, 11 August 2006 (UTC)

In which disambig page ? Mion 19:14, 11 August 2006 (UTC) , and read the first part of the sentence, If the water fuel cell has its own article it could be referenced on, the second part was my personal view. Mion 19:14, 11 August 2006 (UTC) thats why i put it back.

and another one, there are loads of patents given on the design, it has the design of a fuel cell, the fact that we didn't see one working , tja.Mion 19:14, 11 August 2006 (UTC)

It isn't a real fuel cell, the disambig tag at the top of the page links to the article in question, and you haven't given a justification which fits with the goals of the project. It's pretty disingenuous of you to ask "which article" without actually doing a search for "water fuel cell". Chris Cunningham 21:53, 11 August 2006 (UTC)

ok, i missed the top link to the disamb page, and which article, did i ask you  ? well , i think it still belongs in the history section of fuel cells, or are we making only an article about fuel cells that where succesfull ? in that case there is more to clean out. reg. Mion 23:24, 11 August 2006 (UTC)

This article is about fuel cells which fit the description given in the intro, i.e. which take hydrogen and oxygen as fuels. The water fuel cell works the other way around, so it isn't a "fuel cell" as per this article. It is mentioned, in the disambiguation tag. It isn't part of the history of fuel cells as per this article. Chris Cunningham 07:22, 12 August 2006 (UTC)

Yes, which takes hydrogen and oxygen as fuels to create a current. see Reversible fuel cell. reg. Mion 11:26, 12 August 2006 (UTC)

A speculative stub does not an argument make. Chris Cunningham 12:46, 13 August 2006 (UTC)

well, can the process be reversed in a fuel cell? Mion 13:45, 13 August 2006 (UTC)


First, the fact that the water fuel cell was granted a patent is absolutely irrelevant; in fact the patent was granted on the basis of construction of the invention, and not on whether the invention actually works.

Second, Nope, a fuel cell does not have to be used with H2 and O2 only, don't forget direct methanol fuel cells, solid oxide, etc etc etc. What characterizes the fuel cell is not the reactants it uses, but the exchange of protons between the cathode and the anode via dielectric media. --Fieraloca 04:15, 7 February 2007 (UTC)

[edit] DCFC

http://www.wired.com/news/planet/0,2782,69713,00.html Mion 13:12, 16 July 2006 (UTC)

[edit] Turning off vs. continuous operation

If the water is not evaporated quickly enough, it reduces efficiency, and if it is evaporated too fast, it can crack the fuel cell. So, if used in, say, an automobile, does it have to keep operating all the time even when the car is parked, or can it be shut down, unlike the ones used in the Apollo space missions? (Jim Lovell on Apollo 13 knew that if they shut down the fuel cells as Mission Control told them to, they could not be restarted.) GBC 17:21, 11 August 2006 (UTC)

Yes, they can be started, but it will take some time before they operate at full efficiency (depending on type: SOFC take a full 8 hours!). More than cracking, the dry-out causes an increase in internal resistance (it just does not work), but such PEMFC systems usually come with an humidifier. As for the Apollo, they used quite primitive alkaline FC technology... I do not know the details, but they were probably short-lifespan gizmos (after all they had to last for a few days only) assembled thinking more about saving weight than flexibility in usage. Come think of it, there is at least one type that must be operated continuously, the PAFC (phosphoric acid): below 41˚C the acid solidifies, and good luck warming it up again... but PAFC are almost ignored nowadays.


Once the membrane is hydrated within the break-in period of a new fuel cell, full performane can be achieved within minutes. Continuous operation is not necesary. Water is not evaporated from a fuel cell; the gas diffusion layer moves the water into the flow field of the current collectors.--Fieraloca 08:34, 12 November 2006 (UTC)

It should be noted that start up time depends heavily on type of FC, modern PEMFCs can start within a few seconds. The startup time of a fuel cell system usually depends on time required to get the ion conductivity layer to produce adequate conductivity for the current required. Nafion, a popular material for PEMFC ion conductivity layer (electrolyte) can operate lower than 0 C (32 F). SOFCs need to reach about 600-800 C to start conducting ions for efficient operation.

[edit] Fuel cell definition

Oxford dictionary: • noun:

  • a cell producing an electric current direct from a chemical reaction.

[[1]]Mion 11:52, 11 September 2006 (UTC)

the indefinite article does not denote that any device matching that short description is a fuel cell, any more than a definition of a crow as a "black flying object" implies that cannonballs are crows. Consensus has been shown to be in favour of leaving this article only for devices matching the scientific definition of a fuel cell as a device which creates electricity through oxidation. Chris Cunningham 14:18, 11 September 2006 (UTC)
I cited a reference, the Oxford dictionary: can you give me an equal valuable reference on the scientific definition of a fuel cell ?
If consencus has been reached, ok , where can i find it ? if not the first part of the article has to be rewritten.
or the other way around, if i cant hold my argument i am going to revert it myself. Mion 14:29, 11 September 2006 (UTC)
Try some specific literature like "Fuel Cell System Explained" by Larminie and Dicks, it is a common textbook in the subject. You should find it in any university library.
The reasen why there was a discussion :[[2]]. result. stays as it is.. al thanks for the help. Mion 10:22, 29 September 2006 (UTC)

[edit] Need help in writing an article about Pure Hydrogen-Air Fuel Cell

Hi Mion or Anyone can help-- Please. . .

As ESL (English as second laguage) person I need help in writing an article on what I beleive it could be a break through in Fuel Cell research.

I have found in the setting of embrittled aluminum as anode, stainless steel as cathode and water as electrolyte one can build Hydrogen-Air fuel cells; I have it test run for hundreds of hours, no membrane or catalyst required; This will be:
The least expensive to build.
CO and CO2 Immune.

If you can help me in anyway please foreward me a note at ephitran at gmail.com

Many Thanks.

Phi

My advice is that you get in touch with the electrochemistry department at your local university. Write them (in your own language) a short abstract about your experimental setup and analysis, and I'm sure they will either help you or tell you why your invention doesn't work (My guess is the power density is too low). You will need to have a peer-reviewed publication elsewhere before you can post an article on Wikipedia, since original research is not allowed here. Good luck. --PeR 09:19, 2 October 2006 (UTC)


You are talking about a galvanic cell. Yes, you can get a galvanic potential when you place certain dissimilar metals together e.g. zinc and copper. There's no particular use for such as power source in real life.--Fieraloca 08:29, 12 November 2006 (UTC)

[edit] CHP efficiency

The paragraph about combined heat and power (CHP) appears to contain contradictory information. It states that fuel-to-electricity conversion is "typically 15-20%". Toward the bottom of the same paragraph, however, it states that PAFCs, which dominate the CHP market provide electric conversion efficiencies typically around 45-50%.

I don't know which range of numbers is more accurate, but it would seem that at least one of them is wrong. --jfinlayson 10:59, 18 October 2006 (UTC)

[edit] Proposed correction to Fuel cell issues

"Water management (in PEMFCs). In this type of fuel cell, the membrane must be hydrated, requiring water to be evaporated at precisely the same rate that it is produced. If water is evaporated too quickly, the membrane dries, resistance across it increases, and eventually it will crack, creating a gas "short circuit" where hydrogen and oxygen combine directly, generating heat that will damage the fuel cell. If the water is evaporated too slowly, the electrodes will flood, preventing the reactants from reaching the catalyst and stopping the reaction. Methods to dispose of the excess water are being developed by fuel cell companies."

Fuel cells virtually never run at an ideal condition, where "the same amount of water generated is PRECISELY evaporated". The gas diffusion layers (GDL) take care of the water management. If you have ever ran a fuel cell, you would know that the excess water is continuously discharged through the cathode side. --Fieraloca 08:17, 12 November 2006 (UTC)

This phrase: "In 2008 UTC Power has 400kw Fuel cells for $1,000,000 per 400kW installed costs." is confusing. If it is "per 400kW installed cost" it is redundant. The intersting data here will be the cost per kW. --Nachoj (talk) 15:58, 27 April 2008 (UTC)

[edit] Propose to modify chart

Propose to remove Metal Hydride Fuel Cell MHFC and Direct Boro-Hydride FC from the chart of different types of fuel cells.

Metal hydrides and Sodium-Borohydrides are HYDRIDES not fuel cells. They are H2 storage media. The H2 obtained from these two types of hydrides are usually fed into PEMFC.--Fieraloca 08:21, 12 November 2006 (UTC)

Oppose removal of Metal Hydride Fuel Cell (MHFC). MHFC is in fact a variant of the alkaline fuel cell; the metal hydride may be used as either a hydrogen oxidation catalyst or as a hydrogen storage medium that is integrated into the anode.
It is arguable that Direct Boro-Hydride FC should also remain on the list due to the unique technical challenges and operating points resulting from the use of a liquid fuel source, much as Direct Methanol Fuel Cells are often classified as a different type of fuel cell.
Perhaps it would be helpful to break the classification into a "major" and "minor" scheme, where the "major" categories are AFC, PEMFC, PAFC, MCFC, SOFC, and then variants like the MHFC, DBHFC and DMFC are "minor" categories.
Thopper 03:59, 7 November 2007 (UTC)

[edit] Correction to fuel cell efficiency

Using cell voltage as an indicator of efficiency is the biggest non-sense that I have ever heard!!!

Example: Take a perfect fuel cell; at an open cell potential of 1.23V, the current is Zero, thus the amount of H2 consumed is also Zero. Which means that you have just invented a perpetual motion machine, no need to feed H2, just 1.23V of pure Potential?!?!?

The efficiency of a fuel cell has to be measured as a ratio between the amount of energy obtained Vs the total enthalpy differential. Or other methods would also be fine.

--Fiera 08:52, 12 November 2006 (UTC)

In calculus there is the idea of limits. The open cell potential is always an ideal approximation - you measure it with a multimeter that draws a few picoamps, never 0. Similarly, the amount of H2 consumed due to these picoamps is a few femtomoles, which is still quite a few atoms considering avogradro's number is about 6x1023. When you talk about voltage, or potential energy in general (voltage in an electric forcefield, height/pressure/liquid head in a gravitational forcefield, pressure/spring constant in an electric forcefield between atoms), you always talk about rate of change, energy gained vs. distance traveled, motion. It's how much energy I would get per foot if I traveled north down this hillisde, there is an idealized answer to that, similarly like there is an idealized answer to an open cell potential, how much energy you would get per electron flowing through your wire, how many volts it carries. But you don't actually get any energy if you don't take a step, just sit still. Measuring the energy you have to move by a millimeter down the hillside, record the results to calculate how much you would get per meter. Similarly, if I have a pipe with 20 psi pressure of water meaning each cubic centimeter could give me such and such energy if I let it flow through my turbine/electric generator, the higher the pressure the more energy I'd get per cc of liquid. Staring at the pressure gauge on the pipe expressing to me the "pure potential" does not mean I have a perpetual motion machine because nothing is moving. In fact all pressure gauges obtain their reading by moving, whether a few millimeters against a spring load, or a few nanometers against a piezoelectric membrane. Sillybilly 13:12, 12 November 2006 (UTC)


Uhm... yea... i think i was being sarcastic when I said I invented the perpetual motion machine. What I am referring to is the following quote from the main fuel cell page, under "efficiency":

The efficiency of a fuel is very dependent on the current through the fuel cell: as a general rule, the more current drawn, the lower the efficiency. A cell running at 0.6V has an efficiency of about 50%, meaning that 50% of the available energy content of the hydrogen is converted into electrical energy; the remaining 50% will be converted into heat. For a hydrogen cell the second law efficiency is equal to cell voltage divided by 1.23, when operating at standard conditions. This voltage varies with fuel used, and quality and temperature of the cell. The difference between enthalpy and Gibbs free energy (that cannot be recovered) will also appear as heat.

What I'm saying is that this entire parragraph is pure non-sense. Whoever wrote this believes that the current stays constant with changing cell potential, that energy is measured in Volts, and that the open cell potential would yield a perpetual motion machine. Paragraph will be deleted unless objected by anyone. --Fieraloca 04:45, 7 February 2007 (UTC)

I would suggest to ask an electrochemist to clarify this point. The entry about fuel cell efficiency and thermodynamics ruins the quality of the whole article. I would suggest taking the whole section out until someone with a background in fuel cells can take a shot at it. My criticism as a reader, not an editor, would be as follows:

Fuel cells are just as much thermodynamic devices as anything else in the universe. The second law holds and the Carnot Cycle is indeed a hard limit for fuel cell efficiency, except that it is not obvious what temperatures to throw into the Carnot limit equation. If I had to wing it, I would say that the lower temperature has to be the temperature at which the cell operates, and the upper temperature is probably the theoretical combustion temperature of the ideal fuel/oxidizer mix (at the partial pressure equivalent to the concentrations of the fuel and oxidizer?). Since that temperature is very high compared to the cell temperature, the Carnot limit will be somewhere above 90%. Now, the reactions inside a fuel cell are not equivalent to a Carnot Cycle because there is interaction between the fuel, oxidizer, the solvant and the electrodes, therefor the theoretical efficiency has to be less than the prediction of the Carnot Cycle. Any real science argument would obviously start with the well known ways to calculate dynamics of ionic reactions in solvents in, not the basic equations of thermodynamics for beginners.

I am a physicist, not an electrochemist and I do not have the detailed knowledge of fuel cell chemistry required to explain this quantitatively or even qualitatively. Anything I could write would therefor not approach a scientific quality standard. All I can tell is that the way it is written right now leaves a very bad impression to those with even a minimum of physics literacy. --[J.L.]

To my understanding, the Carnot equation was derived under the assumption that the device in question works by taking in heat from a "hot" reservoir, and later rejecting that heat to a "cold" reservoir. The energy input to a fuel cell is not in the form of heat at all, but of chemical energy. Redefining terms in order to force the Carnot equation to apply does, as you have indicated, require lots of mental gymnastics involving the notional "temperature" of chemicals undergoing non-equilibrium processes.
In the same way, applying this equation to electric motors would require that a copper wire at exactly 300K with 10V applied vs. ground would be somehow much "colder" than an identical wire at exactly 300K with 110V applied to it (let's see...kΔT = 100eV...that's a huge ΔT!). This, even though negligible heat would flow across a diamond placed between the two wires.
In my experience, thermodynamics are applied in these instances by regarding structured energy as separate from heat, and applying the second law in ways more general than Carnot. This allows us to preserve our traditional notions of temperature.--Joel 20:54, 13 April 2007 (UTC)
I agree with JL and others who state that the following text is, at best, nonsense. I'm moving it here until someone can rewrite it to make sense. I'm moving it here because the issue was brought up over six months ago and hasn't been fixed. Mkultra72 21:55, 21 June 2007 (UTC)
The efficiency of a fuel is very dependent on the current through the fuel cell: as a general rule, the more current drawn, the lower the efficiency. A cell running at 0.6V has an efficiency of about 50%, meaning that 50% of the available energy content of the hydrogen is converted into electrical energy; the remaining 50% will be converted into heat. For a hydrogen cell the second law efficiency is equal to cell voltage divided by 1.23, when operating at standard conditions. This voltage varies with fuel used, and quality and temperature of the cell. The difference between the reaction's enthalpy and Gibbs free energy (that cannot be recovered in any case) will also appear as heat, along with any losses in electrical conversion efficiency.
The text that you removed is completely correct, so I'm going to put it back in. However, it's apparently misunderstood by many readers. The reason why efficiency is proportional to voltage is that the fuel consumption is proportional to current, and power output is proportional to voltage times current. The reason why voltage drops when current is increased is a combination of ohmic losses, reaction kinetics, and mass transport. --PeR 21:17, 23 June 2007 (UTC)
The text that I removed is not even wrong. If it is misunderstood by many readers then it is badly written. Current is proportional to voltage at a fixed resistance, your statement fails to explain at what current (or resistance) the given efficiency holds. Disputed unsourced statements stay out until a source is provided. There are several unsourced statements in the above text that are being disputed by me and by several other people on this talk page. Please provide a source which says _both_ that efficiency is dependent on current _and_ efficiency is 50% at 0.6V. Thank you. Mkultra72 13:12, 26 June 2007 (UTC)
I never said that voltage is proportional to current. Read my text again. Almost any textbook on fuel cells will serve as a reference. The one I refer to most often is "Electrochemistry" by C. H. Hamann et al. (See section 9.7: "Efficiencies of batteries and Fuel Cells".) --PeR 15:32, 27 June 2007 (UTC)
You're right, you didn't say V is proportional to current. In that case I'm completely missing your point. Are you telling me (before I go to the library and look up the reference you're providing) that the section you're citing supports every specific statement in the unsourced material you insist on reinserting? If so, provide an inline cite in the article. I will double check your reference so you should make sure you're right. (p.s. That text is currently checked out of the library, so it wil be a couple of weeks before I'll be able to double check your reference. When you include your cites in the article please provide page numbers because I don't want to have to read through a hundred pages just to verify that your cite supports your statements.) Mkultra72 20:01, 27 June 2007 (UTC)
I say the text is right. It's a consequence of the 2nd law of thermodynamics that only "quasi-equilibrium cyclic processes have a 0 entropy change". Anything else generates entropy. To have a quasiequilibrium process you need to proceed infinitely slowly, and it takes and infinite amount of time to harvest the energy. Basically, the farther away you are from equilibrium, the more energy is wasted to generating entropy and the less is harvested as useful work. Sillybilly 20:56, 26 June 2007 (UTC)
We're basically talking power supply efficiency. Any electric power supply (such as a wall socket, a fuel cell, etc) can be approximated by an idealized voltage and an internal resistance. The internal resistance is the big deal here. Assume you have a power supply with an open circuit voltage of 100V and an internal resistance of 5 ohms. If your load is 10 KOhm, that will draw a current of I=V/R=100/10000=.01 A = 10 mA. Actually it's less, because the total resistance through the circuit is 10000+5 Ohms, considering that internal resistance in the big picture, and the actual current drawn will be less than 10 mA, more exactly 9.995 mA. And the actual "in use", "non-open-circuit" voltage measured at the terminals will also be lowered because of the internal resistance, as in a resistor voltage divider 10000/(10000+5)*100V=99.95 V. You can simply measure this "in use" voltage to calculate that your power supply is wasting 0.05% energy and delivering 99.95% to the load, therefore the "efficiency of the power supply is 99.95%." The actual "useful" wattage through the load is 99.95V*9.995mA=0.99900025 Watt, a very slow drain. Now take another scenario - assume your load is 1 Ohm. In this case the 5 Ohm internal resistance of the power supply is no longer "negligible." In this case the idealized power supply would deliver 100 V/1 Ohm=100 Amps, but because of the internal resistance it only delivers 100 V/(1+5) Ohms=16.7 Amps, and that's a big difference. Also, the voltage you measure on your power supply rails is 1/(1+5)*100=16.7 Volts, as opposed to 100 V you're expecting. You can "say" your power supply is delivering 16.7% efficiency, and wasting the rest on its internal resistance as heat. In this case the power delivered through the load is 16.7V*16.7Amps= 278.89 W, a very large drain giving a low efficiency, compared to a very slow drain giving a very high efficiency in the previous case. The internally wasted heat is I2R=16.72*5=278.89*5=1394.45 W, and the actual "energy efficiency" is 278.89W delivered/total (278.89 delivered +1394.45 wasted)=16.67%. The faster you're trying to milk juice out of any electric power supply will give you a correspondingly smaller "efficiency" and greater internal waste as heat. The way to combat the problem is to drop the internal resistance of the power supply. In case of a wall socket this would mean really fat copper wires and a short distance from the actual energy source (the power plant), and for fuel cells increased membrane area and decreased membrane thickness to drop the resistance, which also has the problem of increasing the chance of a puncture hole giving an internal short circuit. Once you sufficiently drop the membrane resistance, then mass transfer/diffusion could become the limiting factor, in which case you need to increase the agitation/turbulence inside the fuel cell. For a 1 ohm load you would probably choose a power supply with an internal resistance of say 0.01 ohm, while for a 10 KOhm load whether you're using a power supply with 0.01 Ohm or 5 Ohm internal resistance, it doesn't really matter. You can always check how well you're doing simply by measuring the "dynamic", in use voltage on the power supply terminals and compare it to the "static", open circuit voltage. If the two are close, you're doing well, if the voltage dropped significantly, you're wasting a lot of energy. Sillybilly 22:28, 29 June 2007 (UTC)

Mkultra, if that book was checked out, then just borrow any book on fuel cells, and read the chapter that discusses the efficiency. Since you're missing my point I'll try to make it more clear:

Efficiency = output power / reactant energy flow
Reactant energy flow = constant * current (We'll disregard leak currents and wasted reactant for now)
Output power = voltage * current

Combined, these three equations give:

Efficiency = voltage / constant
The section (9.7) that I referred to above actually discusses first law efficiency, and in that case efficiency is Vcell / 1.48, not Vcell / 1.23, so it's not an exact match. I could probably find an exact reference if I searched a bit, or rewrite the section to discuss first law efficiency instead (which is the most commonly used definition of efficiency anyways), but I can't be bothered right now.

If you don't now enough on the subject to say that the text is wrong, then you're better off letting the people who do know the subject decide on whether the text should be removed, referenced or not. I'll not revert you any more. I suspect somebody else will do it soon, and otherwise I hope you revert yourself once you've gotten that book from the library. --PeR 21:06, 27 June 2007 (UTC)

When you provide a reference for text that you insert, I'll check the content you insert against the reference you provide. What I know or don't know about the subject matter is actually immaterial. Knowledge of the subject matter is one skill required in writing content. Communicating the subject matter effectively is another important skill. Being able to back up what you say with references is another important skill. The explanation you've given above clearly demonstrates (to me) that Efficiency=voltage/constant. But the key point (that several people have brought up on this talk page) is that the statement that Efficiency is dependent on current (which strongly suggests that the author didn't understand the difference between current and voltage, whether or not this is true.) Which brings back the point that the content is (at best) poorly written. But if your source also states that efficiency is dependent on current then I'll at least leave it be (but I do hope you'll find someone to rewrite it to make it more clear to those of us who don't understand the subject.) Mkultra72 02:25, 28 June 2007 (UTC)
Here's a list of articles that all contain graphs showing that voltage decreases with increasing current [3]. Will you please restore the text now? --PeR 05:26, 28 June 2007 (UTC)
I've been fairly consistent with my message, but it still seems to me that you don't understand. This is the last time I'll explain it to you. The text I removed doesn't make sense: it needs to be rewritten, truth is irrelevant. The text I removed has no source: sources need to be provided, truth is irrelevant. I will not respond on the talk page again until these issues are addressed. Mkultra72 23:40, 28 June 2007 (UTC)
I've been fairly consistent with my message, but it still seems to me that you don't understand. (So we agree! :-) The text does make sense, but you don't have the background knowledge to get it. The text is useful to some people, therefore should not be removed. If you think the prose is bad, then make it better. If you can't improve it then you're better off editing articles where you do understand the subject. I have now edited the text to try to make it more accessible to people with no background in electrochemistry. --PeR 06:46, 29 June 2007 (UTC)


PeR, The statement is absolutely wrong and should be deleted!!!!! You are trying to explain a very complex thing (fuel cell efficiency) though Voltage only? You are completely disregarding the stoichiometric flow through each cell!! Are you saying that a cell running at 0.6V and a stoich of 5 has the same efficiency than a cell running at 0.6V and a stoich of 1.2???? You assume constant current? Oh wait, you are ALSO assuming constant stoich. ok.

How about O2 diffusion efficiency? air contains 20.9% O2, your statement does not address how the diffusion plays a role in efficiency and real Vs theoretical stoichiometric values at the reactions sites. Nor does the statement address catalyst utilization/ reactivity. And you do not address proton trasport resitance. And crossover? So that too? you are also assuming that these factors are constant?

Let me see if I understand your statement. If every single operating parameter of a fuel cell is kept constant. Then efficiency is measured with voltage.

Trying to explain efficiency by Voltage only, is a little bit of an oversimplification, dont you think?


--Fieraloca 23:32, 12 November 2007 (UTC)

[edit] The Birth of the Fuel Cell - But Who is the Father?

One cited article [4] in the history section claims that the fuel cell was not invented by Groove in 1839, but by Schoenbein, and that Groove did not build a fuel cell until 1842.

Most fuel cell related articles, in the "background" or "history" section will cite Groove as the inventor and the year as 1839. (See, for example, [5] or [6])

Does anyone know the truth behind this? I think the article needs to be clarified.

--PeR 12:31, 29 November 2006 (UTC)

[edit] Vehicles

There is mention of cars and other vehicles that use fuel cells but not other vehicles. Perhaps there should also me mention of the first space craft. This submarine also uses Fuel Cells. I do not know if there were any before it. http://en.wikipedia.org/wiki/Type_212_submarine

Yewenyi 04:12, 6 December 2006 (UTC)


[edit] Current or Voltage

Consider the following section:

The efficiency of a fuel is very dependent on the current through the fuel cell: as a general rule, the more current drawn, the lower the efficiency. A cell running at 0.6V has an efficiency of about 50%, meaning that 50% of the available energy content of the hydrogen is converted into electrical energy; the remaining 50% will be converted into heat. For a hydrogen cell the second law efficiency is equal to cell voltage divided by 1.23, when operating at standard conditions. This voltage varies with fuel used, and quality and temperature of the cell. The difference between enthalpy and Gibbs free energy (that cannot be recovered) will also appear as heat.

This is confusing. Firstly, it says the efficiency is current dependent. Next, it gives an estimate of efficiency for a particular voltage. This needs to be clarified.

Ordinary Person 06:28, 6 December 2006 (UTC)


Paragraph should be deleted. Inaccuracies cited under discussion --- Correction to fuel cell efficiency ---

Fuel cell efficiency is dependent on several factors (stoichiometric flow of reactants, recirc vs non-recirc systems, parasitic loads, humidification of reactants, cell impedance and resistance, diffusion properties of the microporous layers, catalyst activity, etc etc etc. Voltage alone says nothing.--Fieraloca 04:54, 7 February 2007 (UTC)

[edit] $30/kWh

Someone wrote that it would be reduced to $30/kWh. If you read the reference closely, that's not what it actually says. I'll correct this, but I thought I'd note it here too.

[edit] New fuel cell developed

It is a simpler design and is more efficient. It is expected to first be incorporated in smaller engines like those found in lawn mowers. That should make in impact, since they are not regulated.[7] Brian Pearson 23:05, 16 January 2007 (UTC)

[edit] Micro fuel cell demonstrated by Japan Steel Works at FC Expo 2007

Take a look at [8]. DFH 20:31, 8 February 2007 (UTC)

[edit] Future technology?

New offshoreship with FC tech coming soon [9] --OddMartin 23:42, 22 February 2007 (UTC)

[edit] Trivia Section

This section gives the impression it was only set up so the high school band and Ballard systems could be mentioned. If there has to be a trivia section, it needs a list of unbiased bullet pointed sentences, until then I think its best I remove it.

[edit] Question

User talk:80.123.226.133 asked about Fe + 2FeCl3 = 3FeCl2 + energy. I found one Google hit. Could someome discuss it with him/her? Simesa 13:42, 26 April 2007 (UTC)

[edit] GE provided 6kW SOFC to DoE

Anyone seen this? Efficiency of 49%. October, 2006: [10] Simesa 00:11, 30 April 2007 (UTC)

[edit] mechanism doubted

"In the archetypal example of a hydrogen/oxygen proton exchange membrane fuel cell (PEMFC), which used to be called solid polymer electrolyte fuel (SPEFC) around 1970 and now is polymer electrolyte membrane fuel cell (PEFC or PEMFC, same as the short writing of proton exchange membrane) while the proton exchange mechanism was doubted," I don't get this. What happened while the mechanism was doubted. Is this thing still happening or did the doubt stop? --Gbleem 12:17, 22 May 2007 (UTC)

[edit] H2O

so if we go H2 + O2 ---> 2H2O, aren't we trapping O2 (breathable oxygen) in H2O molecules? won't we eventually run out of O2? Sahuagin 01:39, 28 May 2007 (UTC)

Pending an expert dropping by to give us a proper answer, here's a quick and unnuanced overview: The idea is to give a clean-at-the-point-of-use and transportable form of energy. The energy could have been produced via electrolysis from a renewable or nuclear source, in which case the equivalent amount of oxygen is released in the process. (As wind, water and photovoltaic power are not constant, making hydrogen fuel as a form of energy storage is seen as a key application of the technology.) If fuels are to be used as the source, they would have been burnt anyhow! The oxygen cycle renews this oxygen via plants, a process which of course is closely linked to the carbon cycle.--Old Moonraker 06:57, 28 May 2007 (UTC)
ah thank you. i was unaware that H2O was broken down in photosynthesis as well as CO2. much thanks. Sahuagin 23:03, 6 June 2007 (UTC)

[edit] History part?

UTC's Power subsidiary was the first company to manufacture and commercialize a large, stationary fuel cell system for use as a co-generation power plant in hospitals, universities and large office buildings. UTC Power continues to market this fuel cell as the PureCell 200, a 200 kW system.[8] UTC Power continues to be the sole supplier of fuel cells to NASA for use in space vehicles, having supplied the Apollo missions and currently the Space Shuttle program, and is developing fuel cells for automobiles, buses, and cell phone towers; the company has demonstrated the first fuel cell capable of starting under freezing conditions with its proton exchange membrane automotive fuel cell.

In 2006 Staxon introduced an inexpensive OEM fuel cell module for system integration. In 2006 Angstrom Power, a British Columbia based company, began commercial sales of portable devices using proprietary hydrogen fuel cell technology, trademarked as "micro hydrogen."[9][10]

This needs to be moved or removed from the article. It has nothing to do with history that Staxon in 2006 put out a cheap FC...

The UTC part is even worse, it is manipulative, UTC might be the first to put out that specific type of backup power, but Japan have been using stationary power plants for many years. And most hitech firms have some sort of fuel cell production / development going on these days, with my limited knowledge, i do not recall having heard of one car firm using UTC cells in demonstration projects. No doubt UTC plays a major role in developing backup power systems, and due to the instability on the US power grid, there is a major demand for super reliable systems, that can also keep power flowing for many hours, maybe even days, but that should go in a separate article. Unless someone provides counter argument, i will move the staxon part to news, and remove the UTC thing. (Larkuur 14:20, 12 August 2007 (UTC))


Update: Moved Staxon part, since the wikibot considers me a newbie (true), it wont let me delete anything... I still believe any one with the powers should remove the UTC part from the article, maybe move it to the UTC main article. (Larkuur 16:35, 13 August 2007 (UTC))

[edit] Edited "Fuel cell design"; please check it

Hiya, I'm a really bold dumbass who feels qualified to rewrite and even create whole new paragraphs when all I know about the subject I learned from reading Wikipedia. In other words, I know very little about fuel cells, so would someone check my rewrite of the first two or three 'graphs of "Fuel cell design" to make sure I didn't get it completely wrong?

One thing, as noted by User:Gbleem above, is that reference to the "early 1970s" and the proton exchange mechanism not being understood. I moved this, and reworded it to make what sense I could out of it, but there's actually no cite for this claim, and I was tempted to remove it. I decided not to, on the theory that whoever added it probably knows more than me. If it doesn't make sense, tho, someone who knows that should remove it. In any case, I think my layman's introduction paragraph is an accurate overview of the mechanism. Am I right? Eaglizard 21:06, 19 September 2007 (UTC)

[edit] deleted non existent links

Just deleted links to non existent wiki articles Fuel cell system and Fuel cell module. Could someone who has a good idea of fuel cell systems , WGS and PROX start these articles? shampoo 05:59, 27 October 2007 (UTC)

[edit] Fuel Cell Markets

Fuel Cell Markets is one of the leading online resources for Fuel Cells and contains a depth of information on business opportunities, recruitment, products and information about fuel cell resources.

Fuel Cell Markets facilitate the introduction and development of strategic partnerships and joint ventures towards building the global fuel cell supply chain and assisting with the creation of the hydrogen and fuel cell economy.


Piyush.fcm.kumar (talk) 11:47, 12 December 2007 (UTC)

[edit] Water fuel cell

I've added an interesting link to Water fuel cell in the see also section. --CyclePat (talk) 21:42, 19 March 2008 (UTC)