When I see these stories about nanotech hydrogen storage system I always wonder if this is a case where if you could do that economically you could also economically make a nanotech battery or capacitor that could store energy in sufficient density and with rapid enough charging that you would no longer need to use h2.

Is my guess correct? Or will it be significantly easier to make the h2 storage device?

This is also the question I would like to ask. How do the current and projected energy densities for Hydrogen storage compare with current and projected batteries?

Forget storage, let's talk production. We know how to produce electricity cheaply and cleanly (nuclear, hydro, solar, wind) but producing hydrogen either needs to come from natural gas or by using far more electricity to produce hydrogen and store/pressurize it, and so on. Hydrogen's only real advantage in the context of cars is that many claim it can be refueled in a matter of minutes, rather than the 4-6 hours you often see quoted for batteries.

You could make hydrogen out of biomass and sequester the CO2 through pipes back into spent wells. That way, you would be better than CO2 neutral.

You would want the hydrogen in the car and not making electricity to charge batteries. If making electricity is 40% efficient, transimssion is 90% and battery storage is 80% efficient you would have : .4 X .9 X .8 = .288 or 28.8%

The last time I read of "mass-producing" carbon nanotubes they were talking about production with a cost of around $1000 per gram. I doubt these fullerene storage systems are going to be much more cost effective.

H or H2 (notice the abstract says atoms, not molecules) which is it?

Hydrogen may continue to elude our magicans reaching into hats. For a while.

Anyone know how easily the hydrogen can be taken out of these solid state storage materials? My completely uninformed mind wonders why a stored hydrogen atom would want to flow out.

There's no such thing as mass production of hydrogen from biomass either. The bottom line is that transportation fuels are not really the way of the future at our current and projected global consumption levels. Hydrogen, ethanol, and biodiesel cannot be produced on the order of 85 million barrels a day in the absense of oil.

According to Tesla's group and others, the hydrogen fuel cell WTW efficiency is much lower then the pure EVs and PHEVs equipped qith a large enough battery pack.

Why spend so much energy and resources on a difficult, extremely expensive, not so efficient process?

Let's re-route the $$ billions hydrogen R & D funds to further improve and lower the production cost of the Altair-A123-Toshiba-MIT quick charge batteries and EEStor super capacitors and accellerate mass production of PHEVs.

I'm with you Harvey.....

The chemical formula of this stuff is C60Li12H60. It has a molecular weight of 864. One Mole contains 60g of H. I found the density of C60 to be 1.65g/cm3. Ref. This stuff is 20% heavier than C60, so lets assume 1.98 g/cm3. 1l of this therefor weighs 1980g and is 2.29 moles of stuff containing 137.5g of H. 1Kg of H contains 120 MJ of energy [Ref] so this stuff has an energy content of 16.5 MJ/L or 8.33 MJ/Kg.

MJ/kg MJ/L
Liquid H 120 8
gasoline 44 29.0
ethanol 22.61 19.59
methanol 22.61 14.57
C60Li12H60 16.5 8.33
Li-ion battery 0.54--0.72 0.9 to 1.9
NiMH Battery 0.22 ?
Pb acid battery 0.11 ?

the real question would be about the amount of energy required to manufacture this stuff (including the amount requried to manufacture H) and the amount required to extract hydrogen from it.

C60 is easier to make than carbon nanotubes, with a cost several orders of magnitude lower (dollars per gram). That would still be too expensive for this application, though.

About producing hydrogen: you'd either do it thermochemically from coal, and sequester the CO2, or you'd use some sort of mostly thermal watersplitting cycle, either from a high concentration solar receiver or a high temperature nuclear reactor. There's an interesting cycle in which a transition metal oxide, such as a manganese oxide, is dropped through air as small particles through the focus of a high concentration solar receiver. At very high temperature the oxide partially dissociates to oxygen and a lower oxide. The reduced oxide goes through various reactions that ultimately reoxidize it and also evolve hydrogen gas.

If we are looking for lightweight tech here is a reall
wild one. Hope this gets funding as it sounds fantastic.

http://www.sciencentral.com/articles/view.php3?article_id=218392647

EV theme is not a new one. Every 10 years there is new waive of interest about EV. Look, for example, what was written on CALSTART about 8 years ago. EV concept is very well researched, and there is no need to re-invent things like gasoline range extender or battery swap. They were notoriously researched and declined years ago.

While it is generally thought that the problem with EV is battery, it is actually not. The insurmountable problem is battery charging. At the energy level required to propel EV for acceptable range, it is not even theoretically possible to “fast charge” it. No matter what you hear about fast charge, for EV it is not true (unless somebody will invent high temperature superconductor).

The rise of FC was partially inspired by hope that FCV could be conveniently and fast refueled. Again, the main problem of FCV is not that PEM fuel cell is prohibitory expensive, and even not that hydrogen cycle is terribly inefficient. The real problem is that gaseous fuel, and especially hydrogen, is inconvenient.

Nothing else then convenience of liquid fuel will do, at least to personal transportation market. It could be “charged” electrolyte to EV, or liquid hydrogen carrier (hydrazine-like?) for FCV, but before these technologies will emerge EV, FC, CNG, LNG or alike technologies could hope only for niche applications (some times quite big, like CNG buses).

PHEV with overnight charging from regular household outlet is currently the best real thing we have.

Hydrogen has one major strength: Functionally limitless qunatities of it can be stored using fairly simply technologies, if space is not an issue. Hydrogen can be generated from electric sources during off-peak or baseload periods, and stored in simple large tanks. This includes unpredictable "green" sources, such as solar and wind. Moreoever, it can be produced during those moments very efficiently, as high temperature/pressure variants on electrolysis yield good overall thermodynamic efficiency. By contrast, if you wanted to store the electricity directly, in batteries or capacitors, you'd have to spend a heck of a lot more on the storage equipment to be able to pack away the same amount of electricity. One of the biggest issues surrounding green power, now that commercial-grade windmills are reasonably priced, is buffering its inherent unpredictability. Old-fashioned pumped storage is not a bad option, but having a hydrogen option means that your storage capacity is virtually unlimited. Hydrogren begins to make sense when you think about it from the supply side -- it is potentially very easy and green to make; now you have to find something to do with it. Why not put it in cars? To the extent that we try to rush a hydrogen economy into being by burning extra hydrocarbons to synthesize the hydrogen, we're missing the point.

Hydrogen has one minor strength: It can be transferred fairly quickly, so it can travel from one fixed installation to another by pipe as needed, and it can be fed into a vehicle quickly. Current batteries are not nearly as quick, but the prospect of "quick charge" batteries starts to limit the importance of this quality.

The problem is, hydrogen makes a pretty poor automotive fuel. It can burn in an ICE, but not with any more efficiency than other more convenient fuels. It can be put through a fuel cell, but fuel cells cost a lot to make. Storage in a small enough space is a problem, though given enough brainpower, some solution like this one will eventually offer hope.

Hydrogen is not without potential. But given the current state of things, battery-based systems in the EV/HEV/PHEV family seem to offer a lot more environmental bang for the buck, and a lot more quickly, too. Hydrogen might be a good way to buffer green electricity supplies, and reforming NG through a home-size combined heat/electric appliance might improve thermodynamic efficiencies and cut costs. But fuel cells in cars is not the easiest or most sensible road.

"No matter what you hear about fast charge, for EV it is not true (unless somebody will invent high temperature superconductor)."

Please explain.

Andrey - "The insurmountable problem is battery charging. At the energy level required to propel EV for acceptable range, it is not even theoretically possible to “fast charge” it. No matter what you hear about fast charge, for EV it is not true (unless somebody will invent high temperature superconductor)."

Not having invented high temp superconductors A123 has invented nanoscale electrodes that will enable lithium batteries to charge really quickly - about 5 mins.
http://www.a123systems.com/html/home.html

BTW it is not a given that H2 refuelling is quick. Compressed H2 in 10 000 psi tanks could take quite a long time to refill unless the compressor is huge. Liquid hydrogen will be really tricky to refuel. Imagine a leak and something shattering from exposure to -270° hydrogen leaking on it.

Reading the details this has a long way to go before it is practical.

Amminex already has 110 gram/liter and 9.1% weight density using a chemical storage technique. (exceeeding US DOE goal)

http://www.amminex.com/index_files/Page344.htm

BTW there is a good summary of current Hydrogen storage systems at

www.rpi.edu/~goodwc/HydrogenStorage.ppt

NBK:

We are entering the discussion of intrivial technological and philosophical level on your questions here.

Historically humankind moved during its recent technological evolution (more appropriate “revolution” during last 1.5 centuries) to the energy sources/carriers of ever elevating energy density. I mean wood to coal to oil pattern, and also mechanical power to electricity, or steam engine to IC engine to jet turbine pattern. From this point of view conversion to hydrogen gas would be huge step backward counting it low volume/energy density. As any broad and supposedly universal statement, it is more likely reflects our primitive mind and desire to oversimplify nature and human civilization complexity to the sake of impressing the listeners. This argument was used by proponent of proliferation of nuclear fuels, to the extend when highly regarded engineering institution in my home town seriously pursued design of nuclear-powered airplane. Nevertheless, if you suppress the natural to any critical mind attempt to argue it, you probably will agree with it.

Now, as any general philosophical statement, it should realize itself in practical terms. Here they are. Hydrogen gas, as being constituted from smallest in universe atoms, have terrible quality to penetrate through any gasket, seal, or even imbed itself into metal’s surface, making, for example, steel brittle. There is no way to accumulate any significant amount of compressed hydrogen gas because no big vessel would be strong enough to handle sufficiently high to energy storing purposes pressure (same scale effect which prohibit elephant to jump and cow to fly). All means to concentrate hydrogen carry terrible energy wasting disadvantages. Some technologies, however, promise reasonable advantages to hydrogen energy storage – but only on distributed energy level, such as advanced photovoltaic panels.

We already have way more cheap, energy efficient, and convenient means to accumulate energy then hydrogen option. We already have way more energy dense and convenient to handle energy carriers for transportation. I believe that way more appealing from the respective of cost/efficiency options are offered by further development of liquid hydrocarbon energy carriers such as algae biodiesel or mentioned above advanced photovoltaic artificial fuels. To my humble opinion, hydrogen is the fuel of the “future”. And always will be.

Now on fast charge. Current rechargeable batteries (Ni-Mh or to higher degree Li-based batteries) store enormous amount of energy. Converted with 100% efficiency to kinetic energy, these batteries could propel themselves to the speed exceeding of handgun bullet. In order to propel EV for couple of hundred km, buttery of such vehicle should accumulate huge amount of energy, enough to supply high energy output for hours. How you suppose to recharge it fast? In minutes? Use mega Volt conductor? Or wires of human hand diameter? What about switches, contact surfaces, managing circuitry? Do you have any idea how such kind of current/tension are handled on power stations? Do you know that switches are blown by argon gas in order to eliminate electric arc during disconnection?

Generally it is not the biggest problem. The biggest problem is capability of battery to receive such kind of current itself. Any battery has cross-dependent self-discharge, efficiency, internal resistance, thermal dissipation, and run-out limitations. Simply put, any battery has limitation on max power output, defined not only by speed of chemical reaction, but mostly by heat dissipation limit; heat being produced by internal current due to Ohm law of E=I^2*R. As a rule of thumb, battery could not receive any more current that it is capable to produce. That means best recharge time for best current Li-ion batteries is about an hour. Advance butteries probably will double their energy density and double their power density. That means they still will need an hour to be recharged.

Current issue of advanced Li-ion 18650 Li-ion batteries from Sanyo have two modifications. One is high energy, for use with electronic devices, with capacity of 2.7 Amp*h. Another one, with high power capability, for use in power tools applications (and supposedly in EV/HEV) has only 1.2 Amp*h capacity. This is the price to have high discharge/charge capacity. Super/ultra capacitors do have ability to be charged fast. But this is only because they have 100 times less energy density then batteries. You can not cheat Huygens principle.

Ender:
Without any insult in mind to MIT A123 batteries (which are huge achievement), I still skeptical about their fast charge capabilities. For my 20 years monitoring of advances in battery technology, I am historically inclined to divide their claims in 5. I hope I am being wrong on this.

I used to work a little bit with high-pressure gases, and liquid nitrogen (the “mild” one compared to liquid oxygen and hydrogen) too. My everlasting impression of it is that it is highly unpredictable and dangerous s**t.

Re the fast charge idea - it is not as bad as you make it sound Andrey.

A123 and Altair and Toshiba etc can all manage 5 minute recharge with about 100 Wh/kg energy density and very very low internal resistance (and hence heat losses), so the issue is not with the batteries but with the charger.

50 kW and 60 kW EV chargers have been around for ages now, and they look fairly practical to me (see picture below):

http://www.zefiro.com/ev/50kw1.jpg

So park your EV next to two of these (or one larger combined one), and enjoy a 120 kW charge rate. Assuming 5 miles per kWh for an efficient EV, that equates to a 100 mile range for every 10 minutes of charging. That's spot on for the amount of time people would be willing to spend charging a PHEV-100.

P.S. Ender: I probably did not express myself clearly on “liquid hydrogen carrier”. In any means I did not mean liquid hydrogen as convenient trans. fuel. I thought of some kind of liquid-state in normal conditions hydrogen carrying media. Like hydrazine, which is H2-N-N-H2 liquid. On reaction in fuel cell it could (my fantasy) discharge hydrogen and resulted nitrogen could be vented to atmosphere. Too bad hydrazine is fuming toxic chemical with high explosion hazard…

Andrey - you are very sensible to run a million kilometers from hydrazine - it is extremely toxic.

I to do not expect a practical A123 battery pack to be fully charged in 5 mins however I would expect a 'get home' charge of perhaps 20% in this time which would be acceptable. The high rate charge would only be used rarely.

A more likely scenrio is on a long drive, given a range of 400km, is to drive for 350km or so and then stop which you do now in your IC car. Normally you have a bite to eat and a coffee taking half an hour or so in which time your battery has recharged ready to go. You have also recharged and this could enforce safe touring habits of regular stops.

As I said in a previous post the time where anyone can hop in a car and drive 1000km on a whim is getting very close to coming to an end. This convenience has been bought at a price which we will pay sooner or later.

There are simply too many vehicles going too many places at unacceptably long distances. This sad truth is even truer given China's plans to base much of their future on the automobile.

EV or/and PHEV will eventually be implemented on a massive scale. If this is done in a way that maximizes the amount of carbon free electricity used to recharge these vehicles, then it may be feasible to extend the life of the automobile without further massive disruptions to the climate system. In the mean time, further development and/or renewal of cities should be done in a way that minimizes the need for the automobile.

While we debate the perfect alternative to the petroleum fueled ICE, temperatutes continue to soar.

I wonder why don't they try to come up with some standards so that you don't need to recharge the batteries but to replace them. That is, when you keep the car at home, overnight, you recharge the battery, when you're on the highway you go and replace the battery system at a "re-fuelling" sttaion ...

Well if we're going to discuss some fantasy molecule that they have no clue how to fabricate, perhaps we should discuss semiconductive nanotube ultracapacitators, or even better, nanotube flywheels!

E = 2 k R e_s [m^2 / kg]

E = energy stored per unit mass
k = configuration factor, about 0.8 (pure rim is 1.0)
R = radius of flywheel
e_s = tensile strength (unit conversion to acceleration), theoretical maximum for carbon nanotubes is 200 GPa, say 50 GPa with a safety factor.

A carbon nanotube flywheel with a 1 m radius could store 90 GJ/kg! It will spin at about 0.005 of the speed of light! It would probably disintegrate and explode if damaged. Still it kicks the crap out of molecular hydrogen at 142 MJ/kg.

Perhaps I should write this up, publish it, and request some government funding... The two concepts are roughly equally likely to come to fruition.

The flywheel's big weakness is handling the acceleration force that automobile parts and passengers experience. These forces happen in all three dimensions so any pothole could overwhelm the magnetic bearings causing a rapid failure.

I think his point was that such flywheels are as practical as the modified molecule. i.e. neither makes a damn bit of sense for cars, nor do we know how to make either.

On the subject of flywheel storage though, someone mentioned that hydrogen is a great fit for intermittant production sources like solar and wind. It should be pointed out that you could just as easily put a high capacity flywheel underground next to those solar/wind power producers and achieve the same effect without the need for generating and burning hydrogen. I'd be curious to see if flywheels are actually more power efficient on the charge/discharge than generating and burning hydrogen.

Some round trip efficiencies of various electricity storage mechanisms:

Hydrogen/PEM fuel cell: 35 %
Pb-Acid battery: 60 %
Ni:MH battery: 65-70 %
Compressed Air: 70 % (powers compressor of natural gas turbine, so not a closed cycle)
Vanadium Redox flow battery: 70 - 75 %
Flywheel: 60 - 80 %
Pumped Hydroelectric: 80 %
Sodium-Sulfur battery: 70 - 85 %
Li-ion battery: 90 %
Ultracapacitator: 95 %

Sid:

You make a good point that flywheels also have the potential to make a good "overnight buffer" to soak up off-peak power generation. A lot of the pro/con comparison will come down to specific design details -- not fundamental limits of physics -- so there is little to really compare, until we have some concrete performance requirements set down and potential designs on the table.

If EVs are an important part of the future, then there is a lot of thinking and innovation we ought to be doing when it comes to running and managing the power grid. I never learned enough about grid-scale electrical engineering, but it appears to be a fascinating subject.

Andrey:

You make an important point about the tendency towards increasingly concentrated and uniform-quality power sources, but as you admit, that "trend" is an oversimplified view of life. We still derive plenty of power from falling water, even though it is a low-density source of energy. We just convert it to electricity before we ship it. We use increasing amounts of natural gas, even though it has lower energy density (on a standard volumetric basis) than coal. We use what is useful, and we have a knack for making a lot of unusual things useful.

And I don't see where your negative attitude comes from regarding storing hydrogen, at least in a moderately dense form, if not dense enough to use in automotive applications. The Germans were filling airships with hydrogen over eighty years ago and flying them for weeks at a time to all sorts of distant places. Given that, I think we can easily fill a couple large, moderate pressure gas bags with a night's worth of off-peak hydrogen made from some wind farm, and burn it off over the next day to provide peak-demand power. You could even build a small network of pipes to send it to nearby industrial users who have a particular need for it: Food manufacturers (partially hydrogenated vegetable oil), oil refiners, chemical companies, what have you. However, I think we both agree that hydrogen has some serious drawbacks in the automotive segment, and that we will not likely see a practical, purely hydrogen powered vehicle for quite some time, the advance in this article notwithstanding.

And I also think that you need to define the "quick charge" problem with a more concrete range of user-end specifications in mind. I think your unspoken standard is whether it is possible, given a five-to-ten minute fueling stop, to charge a two-ton EV with enough electricity to have a range of 300-400 miles. This would give you the same kind of long-range quick-refuel performance a conventional car would get. It would also be a challenge to charge up, as you point out.

However, I think you would need to do some market research to find out if that level of performance capability is an absolute requirement for all (or most) motorists on the American road -- or how much extra they would be willing to spend to have that capability on-call all the time. Because my bet is that most motorists would be willing to trade in that capability for something much more modest, if the incentives were right.

Since most motorists do not engage in coast-to-coast marathon road trips on a daily basis, I'm willing to believe there is some room in the market for a car, with a 200 mile maximum range, that can take aboard 100 or 150 miles of energy in 15 or 20 minutes. Your problem can shrink or grow considerably with a few strokes of the pen: Taking aboard 400 miles of energy in 5 minutes time requires 12 times more power transfer than taking aboard 100 miles of range in 15 minutes, all else being equal. A0nd I think a 200 mile car with a 100 mile quick-charge (15 min.) capability would be very attractive to a lot of users, especially if its lifetime cost of ownership was cheap.

We can blue-sky a bunch of more radical solutions to the range problem, including battery-exchange stations, pantograph/third rail systems on major rural interstates, generator add-ons/trailers, etc. Some have been thought-out before, some have not been tested as much, but they are beyond our scope here.

Some day we might attain a practical hydrogen setup, but as we often repeat here, it looks like the sort of thing for which we should not be holding our breath.

Robert:

While other technologies might have lower losses, low-pressure hydrogen storage might be cheaper to install and maintain than some of the alternatives, and might be more responsive on power upswings as well. Banks of batteries in particular are not that cheap to build; hydrogren storage can be accomplished in little more than a large metal sphere or flexible bag. Loss rate is an important part of the picture, but not the end of the story for all applications.

NBK:
Some comments.
Hydropower, compared with wind and solar, is quite concentrated source of energy and mean to store the energy too – currently way better than hydrogen promise in future.

Range, rate of fast charge, and acceleration numbers presented by EV and battery manufacturers represent best possible trail results. Consider how battery performance will deteriorate on 3-year old battery pack at hot weather (plus extensive use of AC). Add to equation under inflated tires and aggressive driving, and you get the picture.

As you know, there are two major enemies to long battery life: deep discharge and high current (discharge or recharge – does not matter). These limitations are so severe, that Toyota in their Prius Ni-Mh battery pack uses only 1/3 of it capacity (and never charge it to 100% capacity) to prolong it life. Fast charge represents the most stressful strain on battery, and could not be carried out somehow often. Same thing with long travel.

As I said, PHEV seems to me our best real-life option for foreseen future. Pure electric currently could hope to be employed only in niche applications.

Andrey:

Going over some of what's written here, especially on the more specific automotive issues, I actually think our positions are fairly convergent. We both seem to agree that PHEV offers the most flexible drivetrain, and is the technology most capable of matching current conventional operating convenience within a near-term development timeframe.

We might have somewhat differing views on exactly how large the pure-EV niche is likely to be -- both in terms of what customers want, and in terms what technical capabilities are on the horizon. I probably think that the niche is larger than you anticipate. The only thing to do is follow the technical developments, see what they mean in terms of price and performance, and see how that matches up with what customers want/can afford.

I did not imagine that we would get all our hydrogen or methane from biomass, to run all the cars in the U.S. The U.S. consumes some 140 billion gallons of gasoline per year. The more methods we have for getting transportation fuels from other sources, the more options we have to be less dependant on only one solution.

Quick charging high power battery packs:

Most of us seem to overstate the difficulties with quick charging high power battery packs.

Battery packs can easily be split in 2 or 4 or 8 parallel battery banks (of about 10 Kwh each) that can be recharged simultaneouly, like 4 or 8 track/channel anything.

This way, you reduce the current required 4 to 8 times and you dont need super-conductors. If you use higher voltage such as 660 Volts (common with on-board battery packs) you can quick charge your PHEV or EV in 6 tp 8 minutes without using excessive currents.

Multi-channel (4 to 8, to satisfy various battery packs size) 660 volts chargers may be too expensive for your home garage but would quickly become a standard facility at the corner gas/recharge station.

This would NOT be an expansive facility if used 100 + times a day.

NBK:
Yes, it boils down to most currently obvious : PHEV.
I could only imagine that in twenty years on “Green Electric Car Congress” EV purists will press gasoline PHEV owners “to get out of their gas-guzzlers”.

The main family car would be a PHEV with EV's initially filling some niche roles (commuter car, fun car)

Folks,
This is an article on H2-holding Buckyball. It's not about EV or PHEV.
No one is so stupid to produce H2 from electricity, especially electricity from fossil fuel sources. H2 can be produced directly from coal or biomass by gasification with higher efficiency than electrical generation. H2 can also be produced from high-temp electrolysis at twice the electrical efficiency of normal-temp electrolysis. With proper techniques, H2 can have comparable efficiency from well-to-wheel as electricity in BEV, while H2 has much faster fill-up (recharge) time and no worry about battery degradation, nor battery replacement cost.

The best H2 carrier is in the form of CH4 (methane), the compressed form of which in an ICE-hybrid will get you 3-1/2 times as far as compressed H2 at the same pressure. Forget about Buckyball, hydrides, or other expensive contraption. For local driving, use H2 in a 15-20 gallon compressed tank for ~120 mi range. For long-distance driving, fill up the same tank with CH4 and you can drive up to 400 miles. Now, can any BEV get you that far?

oli:

your formula is incorrect.
I have {E= (1/2)*k*e_s/(density)} in your notations.
density ~ 1340 kg/m3. Three orders of magnitude make difference, don't they?

I'm affraid that nanotube flywheel may always be too expansive for average consumer.Current price of nanotubes is 500$ per kilo (or pound,not sure).
I'm not specialist in that area,but think the strongest
material we are tring to get the more energy we must put
in its creation.For example if nanotubes are 3.000 times stroner than steel we must put 3.000 times mor energy in their creation that in steel.I think there is no easier way because it would contradict nature law.
If I'm right perspectives of flywheels seem to be very doutfull...

Sorry,price of nanotubes is 500$ per GRAM not per pound.