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Discussion Starter #1
Lawrence Livermore Nat Labs create long range hydrogen tank:

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Unfortunately, you can't have a fuel tank that boils away its fuel in an enclosed space like a garage, or you will get fires / explosions. This is a great tech if you want a transfer tank, where hydrogen will be constantly flowing in and out of it, but I see no other use for it.

OR

It would be a great tank for use in sea vessels which will consume the outgassing hydrogen for their fuel cells on long ocean voyages.
 

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Yep, that's what i don't like about hydrogen in general... it's a leaky sonofagun.

Oh yeah, it likes to combust easily (as some would say, "blow up").
 

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Discussion Starter #3
No.

The liquid hydrogen approach requires venting, but there are high pressure vessels lined internally with an impermeable membrane, so that there are no leaks.

The question is, how do you create a tank large enough for shipboard use, as it is difficult to make enormous carbon fiber tanks of the requisite thickness (although scaled composites and rocket manufacturers are making thin walled cylinders for air and space craft).

Very soon, semi-truck tank sized hydrogen tanks that can hold hydrogen at 10 kpsi will be available, but the tank described above will satisfy vessels that can use the vented hydrogen for propulsion.
 

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I know of no substance or material that hydrogen cannot permeate through. Please inform me if my knowledge is out of date.

And to be honest, I still don't like the idea of such high pressures for consumer use. Things break, people screw up, even the most foolproof design has weaknesses and with the extremely large range of combustibility ratios with oxygen, things can quickly get out of hand if something goes wrong. But that's just me. I'll stick with liquid fuels and hopefully soon electrical power.
 

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Discussion Starter #5
I know of no substance or material that hydrogen cannot permeate through. Please inform me if my knowledge is out of date.
Your knowledge is out of date. It is still true that no metal can contain hydrogen gas, but there are polymer sheets that can, and it is these polymer sheets that line the insides of these tanks.

And to be honest, I still don't like the idea of such high pressures for consumer use. Things break, people screw up, even the most foolproof design has weaknesses and with the extremely large range of combustibility ratios with oxygen, things can quickly get out of hand if something goes wrong. But that's just me. I'll stick with liquid fuels and hopefully soon electrical power.
The same could be said of gasoline. Hydrogen is better, because, being lighter than air, it will rapidly dissipate, and will not "wick" into other materials, turning them into a torch, as gasoline does.
 

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If I recall correctly, He (helium) is the leaky stuff; H2 (hydrogen) molecules are decent-sized and "leakproof" isn't all that difficult. The outer shell in He is tiny, so it permeates enthusiastically.

That (possibly erroneous information) aside, why not just leave your H2-powered car plugged in to the house when you're not using it and run the boil-off through the fuel cells and provide power? It's not going to generate a lot of power but that's better than letting it go to waste.
 

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If I recall correctly, He (helium) is the leaky stuff; H2 (hydrogen) molecules are decent-sized and "leakproof" isn't all that difficult. The outer shell in He is tiny, so it permeates enthusiastically.

That (possibly erroneous information) aside, why not just leave your H2-powered car plugged in to the house when you're not using it and run the boil-off through the fuel cells and provide power? It's not going to generate a lot of power but that's better than letting it go to waste.
You know, I may be thinking of helium, as opposed to hydrogen, as H2 is a large molecule, and Helium exists as a Noble gas, yet we have Helium used in some many lighter than air craft, it can't be that difficult.

Anyway, I see no need to allow hydrogen to vent, when there are high pressure vessals that can hold it. That said, there are applications where venting hydrogen is useful for propulsion, like marine vessals.
 

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"Anyway, I see no need to allow hydrogen to vent, when there are high pressure vessals that can hold it. That said, there are applications where venting hydrogen is useful for propulsion, like marine vessals." - Hendler

At the same time, you have to minimize the cost.

Now, I don't happen to believe in the Hydrogen Fairy, so I'm not sure what the current plan is for storing it in a car. If it's liquid, though, the boil-off will happen. Refueling with liquid at normal atmospheric pressure strikes me as safer and more convenient than using pressurized gas.

So, if it's liquid, you can either add complexity and weight by doing something to contain the boil-off, or you can just live with it. If the vehicles will have a battery (and it's my understanding that fuel cells can't easily be power-modulated, so they will have a battery), just use up the H2 that boils off by adding charge to the battery. Or feed it into the grid.

But failure to contain it means that if you go on vacation, you do come back to a car that's lost a lot of fuel. It will have a fully charged (smallish) battery... and Murphy's Law dictates that the nearest H2 station will be out of range.

Now, if we had an easy way to make methanol, I believe there are fuel cells that run on that and, as far as I know, the efficiency isn't much different than H2 fuel cells and methanol is much easier to store. If I recall correctly, 10 gallons of CH3OH has about the same kick as 5 gallons of gas. Add in efficiencies from energy recapture and conversion efficiency and we should be looking at a car with long range that can be rapidly refuelled.

If we can find an easy way to make methanol.
 

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If I recall correctly, He (helium) is the leaky stuff; H2 (hydrogen) molecules are decent-sized and "leakproof" isn't all that difficult. The outer shell in He is tiny, so it permeates enthusiastically.

That (possibly erroneous information) aside, why not just leave your H2-powered car plugged in to the house when you're not using it and run the boil-off through the fuel cells and provide power? It's not going to generate a lot of power but that's better than letting it go to waste.
I think you got them switched, since hydrogen is basically just a single proton with a single electron orbiting it in the 1s shell. Either way though, I'm with you on the not being a fan of the hydrogen revolution. For me, it seems to add big obstacles and complications for relatively minor gains, one of which is being clean power. Great, but the most efficient way of getting hydrogen is to crack it out of hydrocarbon chains, which negates that, and if one cracks it from water, well that's just an efficiency nightmare... why not just cut out the middleman and use the electical power directly?
 

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... because hydrogen can be rapidly refilled into your vehicle, while today's batteries take hours to recharge.
By the time a hydrogen infastructure is in place with all saftey precautions in place, I'll put down $0.25 that battery technology will have gotten to the point where this will be negated.

Room temperature superconductors, c'mooooon!
 

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I think you got them switched, since hydrogen is basically just a single proton with a single electron orbiting it in the 1s shell.
Only true for hydrogen atom. Hydrogen gas is a molecule, composed of 2 hydrogen atoms. Very big difference...
 

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For sure, metals regularly exposed to hydrogen gas becomes brittle. It is in one of the studies conducted by MIT and article published in Technical Review, IIRC. They were studying effects of leaked hyrdogen gas on a lot of stuff, to gauge their effects should hydrogen economy becomes a reality.
 

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Discussion Starter #16
A 650 mile hydrogen tank still does not help with the cost of hydrogen being over $12/gallon gas equivalent.
Given that fuel cells are far more efficient, while gasoline ICE only extract 25% of energy from gasoline for propulsion, that puts hydrogen competitive with gasoline already. Don't compare energy content, compare extractible energy for propulsion.
 

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I'd love to see a hydrogen car explode (in a test), I wonder how much damage that compressed hydrogen can do.
 

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I'd love to see a hydrogen car explode (in a test), I wonder how much damage that compressed hydrogen can do.
Not much, from the tests that I've seen. It burns like fire on hydrogen Zeppelins after the decompression. It would have been really explosive if the compressed tank have oxygen in the proper ratio.
 

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Not much, from the tests that I've seen. It burns like fire on hydrogen Zeppelins after the decompression. It would have been really explosive if the compressed tank have oxygen in the proper ratio.
The only problem is that the proper ratio is 4-100% oxygen for hydrogen to..well..oxidize. Explosively. IIRC.
 

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I too was really fired up about fuel cells last year and thought about getting into the field, as a result I took a very in depth fuel cell class. It was very difficult and also very informative. I can say pretty confidently the fuel cell is very very far from being a reality.
Yes I know there are a few out on the roads now but the problems with the technology are many.

Please give a link to this super film you speak of which can prevent the hydrogen from leaking. I am very interested because there was no such thing last year. The hydrogen leakage is a major problem. Especially if it is in its liquid state. liquid hydrogen is a farce. It must be maintained at 20.27 K above absolute zero…that’s (−423.17 °F/−252.87°C). it takes about 1/3 the potential energy stored in the hydrogen to keep it that cold, not a viable option. High pressure storage is an unpleasant thought which consumers will not be enthusiastic about. Hydrogen burn clear and ridiculously hot…it’s scary…people immediately think of the Hindenburg. The regulations which need to be in place for a hydrogen infrastructure are going to slow everything waaaay down. It took forever for my professor to have his lab approved by the fire marshal…. Basically for this to have any chance there needs to be a MAJOR breakthrough in metal hydride storage(stores hydrogen in solid state by bonding it to metals and releasing it by heating the solid up). As it stands only about 10% of the hydrogen can be recovered and it weights way to much.

Direct methanol fuel cells aren’t all they are cracked up to be because there is a minimum of 20% fuel crossover (it goes through the membrane and combust to make waste heat rather than electricity. Also they are pretty weak and not a viable solution for vehicles.That being said, these cells are likely to be the first ones we see as consumers in computers or cell phones

Polymer Electrolyte Membrane (PEM) are the cell that will go in cars. The huge problem with that is the cold. If the cell goes below freezing the water in the membrane freezes and ruptures the membrane …not good. The solution is either to keep the cell running slowly to heat it up(waste fuel) or drain the cell once a certain temperature is reached. This would mean you would have to sit in your car for 5 minute for it to refill and heat up to 80 degrees Celsius. This is simply a nightmare with no real solution. If the cell has a problem, fixing it will pretty much be impossible. It will have to be replaced and sent to an engineer to fix it. This would be very expensive. Batteries have a similar problems but it is not catastrophic. Cold means slow, not failure, breaking cost thousands not 10’s of thousands.

The price is hardly worth mentioning. They are a full order of magnitude above what anyone can pay.

I’m willing to bet any sum of money that we will see battery technology eclipse fuel cells as long as these initial EV’s get the support they need.
 
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