Hubei (China) - A new form of non-alkali membrane used in fuel cells could allow expensive and rare platinum to be replaced with nickel. If true, the market could soon be filled with much less expensive fuel cells and a changing attitude toward fuel economy in automobiles as fuel cells can be more efficient than internal combustion engines.


Traditional fuel cell

Fuel cells are composed of two metal plates with a membrane between them, with one side traditionally being platinum (or some other "noble metal"). When a fuel source, commonly methanol, is passed along the platinum side of the plate, it acts as a catalyst breaking down the fuel and it's hydrogen atoms into one proton and one electron.

The proton then passes through the membrane to react with oxygen on the other side to create water. The electron continues along the metal surface, serving as the source for created electricity. Heat is also generated, though not nearly as much as burning the fuel in an internal combustion engine.

Platinum has been used because the membrane material (typically a polymer electrolyte called Nafion) creates a highly corrosive acidic environment, and platinum remains completely stable when exposed to it.

The new fuel cell uses a different type of construction and membrane which is not acidic, allowing far less expensive nickel to be used as the catalyst in platinum's place.


New fuel cell

A Chinese team led by Lin Zhuang at Wuhan University has created a new polymer electrolyte fuel cell (PEFC) comprised of hydroxide ion-conductive polymer, quaternary ammonium polysulphone, an alkaline electrolyte and nonprecious metals such as chromium-decorated nickel and silver. Their work is published in Proceedings of the National Academy of Sciences.

The team has also modified the catalyzing surface of nickel with chromium, a toxic substance recently added to the banned list of hazardous materials prohibited for use in the auto industry (at least without adequate ventilation during chrome plating processes as some sources are being grandfathered into place). This plating reduces its susceptibility to oxidation over time, extending the "efficiency life" of the fuel cell.

Basically, the new fuel cell is not as corrosive as the old one internally. And because of this, and also because of the way the surface of the chromium-decorated nickel has been altered, the fuel which passes into the system can be broken down without degradation over time.

According to the paper's abstract, the new design "remains completely free from noble metal catalysts in both the positive and negative electrodes," which makes it much less expensive by using cheaper metals as catalysts. In addition, the discovery "represents an important advancement in the reserach and development of fuel cells."

A working prototype of the new fuel cell delivers 50 milliwatts per cm² at 60 Celsius. "The power output is still lower than that of fuel cells using platinum, but such a comparison may not be appropriate because platinum fuel cells have been studied and optimised for decades," Zhuang says. In addition, most previous PEFC fuel cell solutions broke down above 40 Celsius making them not usable for most commercial applications (like cars).

While this new invention shows promise, it is not yet ready for mass production. However, according to Zhuang, this may only be a matter of time.


Attractive power source

Fuel cells have already been considered as a possible replacement for the internal combustion engine, even with their premium expense and low operational life. They utilize fuel more efficiently through the fuel cell conversion process than by burning it inside an engine. The fuel cell also produces less gaseous pollution and the automobiles essentially become zero-emission vehicles, generating mostly heat and water along with some fuel waste which can be recouped.

Fuel cells have not been readily adopted because of their high cost, largely due to platinum and other noble metals employed. They also have short operational life spans due to their construction. One crack can render the entire fuel cell completely dead.

According to Dr. Jery Woodall, Purdue processor who has devoted a large portion of his academic career to discovering new ways to generate power from hydrogen fuel sources including one he created called AlGal75 (and AlGal80), has said that fuel efficiencies in excess of 75% have already been achieved with platinum-based fuel cells. Though, these typically only have operational lifetimes of 2000 hours or so, and they cost a "few million dollars."

Typical fuel cell efficiencies are around 50%, which is roughly equivalent to diesel internal combustion engines, and about 10% to 15% more efficient than gasoline internal combustion engines.

Error

Dec 16, 2008 11:51     

In the first paragraph: "If true, the market could soon be filled with much less inexpensive fuel cells..." "Less inexpensive?" Do you not mean "less expensive?" [Oui, oui! -Rick]
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fuel cell vehicles...

Dec 16, 2008 14:23     

...are only arguably 'zero emission' at the tailpipe. Energy is used in making & (re)'charging' the fuel cell. Where does this energy come from? [The fuel is produced as it is today, taking crude oil from the ground and refining and distributing it. Or, from methanol or whatever other source. It is still produced, but once it is produced there are very low emissions compared to internal combustion. -Rick]

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CEO

Dec 16, 2008 14:48     

Hi This could be just what the auto industry needs after stalling. We could all go out and buy brand new cars supported by government Green schemes!! Cheers, Nick
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@Gaztronome

Dec 16, 2008 14:52     

And here in Québec (Canada), we use Hydro-Electricity, which is totally Zero-Emission.
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new electric car company

Dec 16, 2008 15:48     

I heard these guys interviewed on the radio this morning, not exactly fuel-cell, but still interesting. http://www.ampmotorworks.com/ Theytake cars and remove the drivetrain, replacing the engine with a battery, and motors on the axels. Curently they are doing this only with Saturn Sky's but they said they can adapt this to any make/model. Hear the interview here (Brian Thomas, 55krc hour 3 on 12/16/08): http://55krc.com/cc-common/podcast/single_podcast.html?podcast=55krcMornings.xml

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wow

Dec 17, 2008 02:35     

Im suprised you guys/gals didn't catch the obvious. Protons do not react with oxygen. I think 'positively charged ions' or cations would be more suitable terms.
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fuel cell / battery hybrid?

Dec 17, 2008 07:55     

It could lead to fuel cell / battery hybrids. The fuel cell could charge the batteries when the fuel cell isn't giving the electric motors an extra boost for speed. This could give the GMC Autonoma car a boost as well as all the other electric and/or hybrid vehicles.
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China on the way towards hydrogen

Dec 17, 2008 11:16     

I am not surprised by this piece of news. France recently announced it did not regard hydrogen as the future fuel. Considering how taxes on petrol are filling the coffers of the french government and their traditionnal short-sighted views on one side and the abyssinal backwardness of the US car industry on the other, it would not be surprising at all were the chinese to be the first to embark in this new revolution.

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And the Carbon?

Dec 17, 2008 12:06     

Where does the carbon go? The only 'green' fuel cell is a H2-O2 cell which doesn't work on the scale people demand (energy density is way too low). This process is the same as combustion: CH4 2(O2 3.76N2)= CO2 2H2O 7.52N2 The only advantage is that your time scale increases and with a catalyst your combustion temperature is much lower, so your NOx production will be zero (excellent btw). This is no miracle, chemistry and thermodynamics still apply. Energy costs are energy costs. NB: If you don't keep the carbon gaseous (CO, CO2, CHx) then the fuel cell will be clogged and rendered useless in a few minutes. [From what I understand, it's not rendered into the air out of a "tail pipe," but can be recaptured via some tank and recycled properly when you go to refuel. -Rick]

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Recyled properly?

Dec 17, 2008 14:16     

[From what I understand, it's not rendered into the air out of a "tail pipe," but can be recaptured via some tank and recycled properly when you go to refuel. -Rick] What does that mean? The energy required to break CO2 into C and O2 is hideous. Doing so would defeat any gains seen in combustion. Not to mention that it's not 'pure' so has no commercial applications, and the compression and transport costs (energy, ignoring money for the moment) would prohibit any 'recycling' program. You guys need to stop adding undue commentary to the science stories you're not experts in. "Fuel cells have already been considered as a possible replacement for the internal combustion engine," and were rejected from a fundamental thermodynamic stand point in the 80's. What is amazing is that they have a cheap micro combustor capable of being fitted to a laptop or cell phone. This would represent a x10 increase in life over a traditional battery solution. This is the real story (what they've been working on for 15 yrs with catalytic combustion). Fuel cells should never power cars. The real car story is buried in the carbon nanotube capacitor story. The energy density, weight and form factor are all there to give a realistic electric (city model) or electric/hybrid (range>40-60km) vehicle without the issues that plague batteries or fuel cells. [Before you say it, I understand the recycling issue with the capacitors won't be any better, being built out of carbon-carbon. They do have a better disposal option though, being inert, if still carcinogenic. Much better fill for asphalt than granite, and we pave a lot. Frankly an excellent hard fiber in any nodular composite.]

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