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Diamonds Are a Fuel Cell's Best Friend
Roland Piquepaille writes "Researchers at UC Davis have used nanocrystals made of diamond-like cubic zirconia to develop cooler fuel cells. Even if hydrogen fuel cells have been touted as clean energy sources, current fuel cells have to run at high temperatures of up to 1,000 C. This new technology will allow fuel cells to run at much lower temperatures, between 50 and 100 C. Obviously, this could lead to a widespread use of fuel cells, which could become a realistic alternative power source for vehicles. The researchers have applied for a patent for their technology, but don't tell when fuel cells based on their work are about to appear."
To my knowledge, there are already LTFC (Low-temperature fuel cells), like PEM, which are already working for years in 50-100 deg C range, but the problem is keeping them below the 100 degrees.
Two years ago, Georgia Tech has announced, that they were capable of pushing it up to 120 deg (source)
and last year, Volkswagen announced the development of a fuel cell working at 160 deg (source).
"Between strong and weak, between rich and poor [...], it is freedom which oppresses and the law which sets free"
It's the other way around actually...CZs are thermal insulators, so they reduce the rate of heat transfer...That's probably one of the key reasons they're being used in this application.
Diamonds, on the other hand, are extremely efficient thermal conductors, so they are quite efficient at heat transfer, making them terribly unsuitable to this sort of application where heat is already the major problem.
So CZ is cheaper, easier to obtain, and (for once) actually has the chemical advantage over the diamond. Cool indeed.
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
There's other alternatives such as Moissanite/Silicon Carbide which is almost as hard as diamond, lighter, higher refractive index, similar thermal conductivity, and more resistant to heat.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
I don't care how cool they make the tank operate at. This was not something stopping them from being used, only increasing their cost due to insulating layers and radiator systems. Great, man made diamonds make them cooler, but at 3 times the cost, and the only benefit is we can reduce the cost of the cooling systems... Hello?
Lets face it, there's no way in hell any of us are ever driving a hydrogen car. Heres a list of reasons why:
1 - If you drive a liquid H2 car, you're driving A BOMB! One that can never be turned off, unplugged, get in a bad crash, or run out of fuel or it will explode!
2 - Solid (metal infused) H2 tanks take approximately 6-8 hours to refill with enough H2 to drive 150 miles. This is MUCH worse than electric only cars. (In fact, using Toshiba's new battery technology, we could refuel electric cars in 90 seconds, to 90% charge.
3 - it's FUCKING expensive!!!
4 - sure the H2 burns clean, but takes 3-5 times as much energy (ie carbon waste) to make it than burning ethanol, meaning its far WORSE for the environment (unless we can make it exclusively from wind, water, or solar power, which reasonably, we can't, but even if we could, it would still be cheaper to build and drive electric cars)
5 - we don't have ANYTHING resembling an industry for transportation, storage, or pumping of H2.
6 - we can't make an H2 pipelines unless the H2 is moved in a gaseous state, not liquid, and the pipes would be too big, too expensive, and too dangerous, not to mention expensive condensing systems required at each endpoint.
7 - what happens if the great big H2 tanks at the filling station are involved in an earthquake, terrorist attack, or extended power outage? Can you say goodbye to 3-5 city blocks?
8 - it's too damned big of a system. Cars would have to be the size of hybrid SUVs and loose either 2 seats or the trunk to run on H2 safely.
9 - There are several safer, cheaper, better, more environmentally sound alternatives, easier to implement solutions.
10 - will you trust a grease monkey to fix an H2 powered engine? (no offense to my many talented automotive engineering friends) Do you have any idea what it might take to fix an engine like this? can it even be repaired at the component level safely?
OK, thats 10 I though up while sitting here. Can you think of 10 reasons why electric cars are a bad solution? Or ethanol hybrids?
There is no contest in life for which the unprepared have the advantage.
The surprise proposal was invented by De Beers. They polled woman and found out that most women, when asked by their partners, would say they would rather that two months salary went to a down payment on a house. So De Beers marketing department convinced men that talking about marriage and discussing the proposal was unromantic, and they should simply surprise their intended with a flashy, expensive ring.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
No, no they're not. CZ is almost twice as heavy by volume. CZ has a substantially different refractive index...Set C and CZ next to each other and examine, and the difference should be clear to even a half-trained eye. CZ doesn't conduct heat well and C does very well. And finally, C will scratch CZ, but CZ will not scratch C.
They may have been hard to tell apart 200 years ago (doubtful), but there is no way a competent gemologist could make that mistake today.
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
Do you think that at the turn of the century, when this campaign was launched and about 10% of people owned their own homes, that women really wanted men to waste two months salary on a ring?
Yes, yes I do. There's a severe social desirability bias in asking a question like that. Few women will admit that a status symbol is more important to them than their long term financial well-being. Looking at how they actually spend their own time and money (i.e. shopping into debt) and how much they like comparing their rock to their friends', says otherwise.
I gave you an example of reading too much into a survey with a severe social desirability bias. It was not a strawman because I was not attacking that as if it were your position, or saying it *was* your position, just that it was a smiliar claim with the same oversight.
Women *do* like surprises. You wouldn't think I'd have to explain this to the "loverevolutionary", but apparently I do.
You come across as a non-rigorous conspiracy theorist, as usual.
Apology to Ubuntu forum.
I second that motion. I think I busted my gluteus maximus laughing. This post should get get an exception to the +5 max mod rule.
ps. Yes, I know it's ass, so don't bother posting a wiseass remark.
The press release, which is phenomenally uninformative, fails to mention that the researches are most probably talking about solid oxide fuel cells. SOFCs use yttria stabilized zirconia as their electrolyte, and it conducts oxygen ions only at a high temperature, 800 to 1000 C. That kind of temperature sets severe limits on fuel cell materials, and therefore researcher strive to drive down the operating temperature of SOFCs. Few hundred degrees down and the range of suitable materials grows much larger.
At the moment, the most common fuel cell type in vehicle applications is the polymer electrolyte membrane fuel cell, which operates usually at ca. 80 C. The scientists are trying to develop PEMFCs that would operate at an elevated temperature, ca. 140 to 160 C. There are three main reasons: Higher carbon monoxide tolerance of the Pt catalyst, easier water management (no liquid water) and easier heat management.
Carbon monoxide is present at least in trace amounts in most fuel feed made by reforming hydrocarbons. Elevating the operating temperature to 160 C increases the CO tolerance from some ppm to few per cent. Conventional PEMFCs need liquid water to remain operational, but excess water obstructs reactant transfer and decreases performance. If liquid water is present in the cell, good water management is both paramount to high performance and pretty tricky.
An average fuel cell power source in a passenger car will probably have an electric power of 30-70 kW, and produce the same amount of power in heat. If the fuel cell stack operates at 80 C and you are driving in, say Death Valley, ambient temperature 45 C, you'd need a radiator size of a refridgerator to expulse that amount of heat. Operating the fuel cell stack at 160 C would alleviate that problem in a notable way.
The aim of science is not to open the door to infinite wisdom, but to set a limit to infinite error.
-Bertolt Brecht
As much hilarity is to be had with the cubic zarconia angle, I'd like to take a moment to say something real...
FUCK THESE GUYS AND THEIR FUCKING PATENTING.
This is technology with real potential to help a debilitating planet, if we started implementing this in 1-2 years, maybe it would actually do something to help save the world from having its natural resources sucked from its insides to the atmosphere. Everyone is so busy raping the planet and trying to get theirs, they don't stop to think about what impact things could have.
That said, I'm investing in these guys and buying a fleet of Hummers when I cash out, just for the sake of irony.
Cheers.
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