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New Generation of Hydrogen Fuel Cells Powers Up
An anonymous reader writes "A safer and more practical way of storing and releasing hydrogen, discovered by two Arizona State University researchers, could lead to a new type of fuel cell capable of packing 10 times more energy. The key is apparently using the alkaline compound borohydride — 'a 30% solution of borohydride in water actually contains one-third more hydrogen than the same volume of liquid hydrogen.'"
Wiki has a decent write up on NaBH4 for those interested and mentions the applicability to Fuel Cells.
This is still in the research/development phase as per the article "Dr. Gervasio recognises that there are still many steps between his prototype and a competitively priced, off-the-shelf, battery-sized fuel cell. Nevertheless, he believes they could appear in power-hungry devices such as laptops, camcorders, and radios within five years." So until then, I'll be using CnH2n+2 to mow my lawn.
Hulk SMASH Celiac Disease
curiously all research lost in a massive fire when a gasoline tanker truck collided with the research building, Big Oil was unavailable for comment.
stuff |
No one ever seems to mention this, but you can get some remarkably high energy capacity and relative stability (it's not going to blow up without a trigger) by using hydrogen-carbon compounds.
Maybe I'm just a kook, but some serious work ought to go towards that sort of research, I think.
Ok, I am confused.....or ignorant.
How does a mixture of Borohydride(not pure hydrogen) and Water(which is already only 2/3 hy
drogen) end up being more hydrogen than Liquid Hydrogen? Isn't Liquid Hydrogen pure hydrogen?
If I am ignorant, educate me....but this sorta reminds me of the line from Anchorman:
"60% of the time it works 100% of the time"
Help me understand.
dimes
One of the major things that are holding Hydrogen Fuel Cells back is the fact that it takes more energy to extract the hyrogen from the envrionment then it produces in the fuel cell. So this makes hydrogen more expensive then fossil fuels, as well more of an inpact on the environment (assuming they are using non-green power generation)
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Although I am not familiar with the chemistry of this research, it is quite possible to pack inordinate amounts of compounds in a solution. For instance, 1 ml (1 g) of water can hold 99 g of the compound used to develop film. The space around molecules in a solution can vary quite a bit, and if the geometries of the solute and solvent match very well to the forces between them, the wasted space can be decreased, increasing the concentration of the solution.
Liquid H2 is not very dense at all. It's density is .068 g/mL (compared to water, which is 1 g/mL). When the borohydride is added to water, you get NaBO2 and 4 H2 molecules.
This post climbed Mt. Washington.
They're probably figuring it on a volumetric basis. Liquid hydrogen is not very dense (71 g/l). I would imagine this solution would be greater than water (1000 g/l). In a mobile application the volume of the fuel would be very important, and storing LH2 is non-trivial due to the temperatures and pressures involved.
Water, on the other hand, is solid and fairly dense at room temperature.
Can anyone spot-check this for sanity?
I dont know about you, but room temperature around here is a bit more then 0C, so 'round here our water is in it's liquid form at room temperature.
Your hair look like poop, Bob! - Wanker.
Who cares about how much hydrogen you can get into a given volume. It should be all about energy per volume. It will be great when someone notices the energy density of hydrogen atoms attached to carbon chains - i.e. hydrocarbons. Oh wait...
Look up (MCEL) Millenium Cell, They've been doing this for awhile. I believe the chemistry for this has been around a while too lazy to look it up tho. Platinum Catylitic mesh, and Borohydride The fuelcellstore has a nice little generator --G
When work feels overwhelming, remember that you're going to die.
It is possible to design nuclear plants to preform electrolysis on the off-hours when the load is low. What does a nuclear power plant do? Boils lots of water. When the load is low, they can run the extra current directly thru the water that was just boiled. Yes, it is not the most efficient power conversion, but we have so much nuclear fuel available why not use it? Sometime in the future we will figure out what to do with the waste. We are a smart race. Worse case we can just launch it into the sun or in a trajectory pointing away from our planet.
Is nuclear that bad? We have known the properties of the splitting atom for decades now... we should have a good understanding of how to utilize this abundant resource. The waste is manageable. Is the waste of a coal plant manageable? Once you spew all that C0_2 and other by-products into the atmosphere there is no (sane) way to recapture it.
Nuclear is our future. Give in to our nuclear overlords.
...should the day Dell announce another battery recall on their new hydrogen-powered laptops ever arrive, I'll be the first to run for the hills.
throw new NoSignatureException();
I'm still waiting for previous generation to be available as laptop battery.
:wq
Liquid Hydrogen is not very dense. The attractive forces that pull it together to form a liquid are weak and only effective a low temperatures. When hydrogen forms molecules its electron tends to migrate towards other atoms slightly increasing the size of that atom's electron shells. A hydrogen atom shrinks right down to its nucleus, not the next smaller shell, since there are no other elcetrons to form shells when it loses its elctron. It takes 779 ml of liquid oxygen and 1586 ml of liquid hydrogen to make a liter of water. Hydrogen is a special case, even with inner shells left, binding forces can lead to higher densities. A liter of Aluminum oxide weighs 3.973 kg of which 1.905 kg is Oxygen. That same 1.905kg of oxygen in liquid form occupies a volume of 1.671 liters.
In the article, they state the energy density of this new fuel is 600 watt hours / litre, with the goal of eventually getting it up to 2200.
According to wikipedia, gasoline has an energy density of 32 megajoules per litre, which if I did the conversion right, comes out to about 8890 watt hours / litre. This sounds like a big difference until you consider that gas engines are typically somewhere around %20-30 efficient. It appears they may some day make a fuel that's roughly equivalent to gasoline.
How difficult is NaBO2 to deal with, and can it be dangerous/toxic?
From Batteries Digest:
The only other reaction product, sodium metaborate (analogous to borax), is water-soluble and environmentally benign.
It uses ruthenium. Ruthenium runs about 175 USD/ounce. Ruthenium is a member the cateogry called "precious metals". It's a rather limited supply item. Given it's other uses I wouldn't expect to see these things be inexpensive. Also menas it will be unlikely to be viable for larger scale applications such as automotive, residential, or commercial power requirements. Still, it is kinda cool.
There is also the question of lifespan and cycling. While the liter of fluid requirement can be worked around, long term issues such as cleanliness of the proces with regards to catalyst maintenance. I'd be cautios about using the phrase "halfway there" just becuase they are using half the percentage of solution they are looking for. While they are at 15% vs 30%, they are also at 600Wh versus the 2200 claimed in the article. Granted, that's theortical maximum, but the effective use of 30% solution is also theoretical.
My Suburban burns less gasoline than your Prius.
...well, at least it was cute and rhymed.
b asics/jtb_biodiesel.pdf
http://www.eere.energy.gov/vehiclesandfuels/pdfs/
"biodiesel can reduce the carcinogenic properties of diesel fuel by 94%"
Biodiesel exhaust != Diesel exhaust.