Hydrogen Storage Remains Significant Barrier to Vehicle Applications
16 March 2006
There are numerous issues to resolve on the path to the possible future widespread application of hydrogen as a vehicle fuel, but of those, the lack of an appropriate storage system currently appears not only to be a barrier, but the area that has proven the least tractable.
“Storage is idea-dependent,” said Steven Chalk, Program Manager for the DOE’s Hydrogen, Fuel Cells and Infrastructure Program, during a panel session at the NHA Hydrogen Conference. “I’m not sure that we have enough good ideas [on which] to spend [the] money.”
Although hydrogen contains nearly three times the energy content of gasoline on a weight basis (120 MJ/kg for hydrogen versus 44 MJ/kg for gasoline), on a volume basis it contains less than 25% that of gasoline (8 MJ/liter for liquid hydrogen versus 32 MJ/liter for gasoline, less for compressed hydrogen).
On-board hydrogen storage in the range of 5-13 kg H2 is needed to support the full range of types of light-duty vehicles currently in use (i.e., light compacts through beefy SUVs).
Accordingly, the DOE established a set of On-Board Hydrogen Storage Targets within the FreedomCAR program are based on, not on what current storage technologies can achieve. The baseline was current vehicles and associated customer expectations of them—e.g., a 370-mile weighted average range.
| Select FreedomCAR On-Board Hydrogen Storage Targets | ||
|---|---|---|
| Parameter | 2010 | 2015 |
| Gravimetric Capacity (specific energy) |
2.0 kWh/kg 0.060 kg H2/kg |
3.0 kWh/kg 0.090 kg H2/kg |
| Volumetric Capacity (energy density) |
1.5 kWh/L 0.045 kg H2/L |
2.7 kWh/L 0.081 kg H2/L |
| Storage System Cost | $4/kWh | $2/kWh |
| Refueling Rate | 1.5 kg H2/min | 2.0 kg H2/min |
None of our portfolio currently meets the 2015 targets—for 2010, 700 bar [compressed] and liquid hydrogen may meet gravimetric targets, but none met the cost targets. And the volumetric targets are difficult, so there is no clear winner for 2010 targets as well.
—Carole Reade, EERE Hydrogen Storage Team, at NHA Hydrogen Conference
The NHA Hydrogen Conference featured numerous presentations on developments in hydrogen storage.
BMW’s liquid hydrogen storage system for the upcoming bi-fuel 7 series. (Earlier post.)
Ovonic Hydrogen Systems described its work in developing an enhancement to its metal hydride storage system with an increase in capacity from 3 kg to 3.6 kg.
Researchers from China’s National Yunlin University of Science and Technology described their work in increasing the hydrogen storage capacity of carbon nanotubes (CNT).
Researchers from India’s University of Rajasthan and the UGC-DAE Consortium for Scientific Research presented their work on increasing the hydrogen storage behavior of intermetallic compounds.
Oregon Sustainable Energy offered up its use of Guanidine, a compound that can be synthesized from ammonia. As a side benefit, “Guanidine is also an attractive fertilizer. If produced in agricultural areas it could be used locally both as fertilizer and fuel.”
Millenium Cell described its ongoing work with sodium borohydride-based solutions.
Researchers from Argonne National Laboratory presented their work on using superactivated carbon adsorption media to enhance compressed gas storage.
Brookhaven National Laboratory is working on using titanium-doped sodium alanate for enhanced hydrogen storage.
Sodium alanate, on its own, is able to store and release a reasonable amount of hydrogen—but insufficient to meet FreedomCAR targets. Brookhaven researchers are using titanium atoms to allow sodium alanate to work more efficiently at realistic temperatures and pressures.
Resources:
Maybe the FreedomCAR goals weren't well thought out like most of this administration's policies. A range of 370 miles for a car is unneccesary. That's 10 days of average use.
Posted by: tom deplume | 16 March 2006 at 12:53 PM
Honda is planning on building a production version of the FCX Concept. It gets 350 miles of range. The Honda Accord V6 gets 354 miles of range. Right in line with the 370 miles that were the basis of these targets. I think that would meet fine with the expectations of most customers. If you combine it with the convenience of home refueling, it's an easy sell. Luckily Honda is pursuing that route as well.
You can read about the FCX Concept here:
http://world.honda.com/Tokyo2005/fcx/
You can read about Honda's plans to produce it in production form in 2009-2010 here:
http://world.honda.com/news/2006/4060108FCX/
You can read about Honda's Home Energy Station here:
http://world.honda.com/news/2005/c051114.html
Offering a vehicle with the same range as a Honda Accord V6 with the convenience of home refueling certainly does not sound like a storage problem to me.
Posted by: H2O | 16 March 2006 at 01:24 PM
Wow what a load.
They have in fact got the range down just fine thank you and far ahead of schedual.
The latest generation of tanks is much cheaper yet stores a good deal more.
Posted by: wintermane | 16 March 2006 at 01:40 PM
(a) The urgency behind fuel cells is entirely artificial: California is mandating that every volume manufacturer sell 2-10% of his fleet (depending on drivetrain mix) as "zero emission" vehicles. Without that, R&D funding would shift to engine downsizing, high-temperature variable geometry turbochargers, diesel emissions, automated dual-clutch transmissions and mild hybrids. Cp. Europe & Japan.
(b) If you absolutely, positively, common-sense-be-damned MUST turn cars into rolling Hindenburgs and the main problem is the poor volumetric energy density of the fuel, the engineering imperatives are straightforward:
1 - put the short-term focus on vehicle segments that can make do with limited range (i.e. city runabouts)
2 - minimize fuel demand through moderate performance, power-centric hybridization (ultracaps, as in the FCX) and optimized vehicle weight
3 - run fuel cell at a higher temperature to reduce radiator size:
http://www.fuelcellmarkets.com/article_default_view.fcm?articleid=11367&subsite=3972
4 - increase fuel pressure (costs extra energy at the pump) but keep an eye on hydrogen embrittling of the tank walls
5 - rob a bank or two to pay for it all
(c) Fuelling up on hydrogen at 700 atmospheres is risky enough if you use professional equipment outdoors at a filling station. Consumer-grade equipment operated indoors (in winter) by large numbers of poorly trained individuals is a recipe for desaster. The fire hazard is MUCH greater than with gasoline.
Posted by: Rafael Seidl | 16 March 2006 at 02:04 PM
Now Rafael surely you understand that Honda is utilizing a new yet to be publicly mentioned adsorbant in their tanks. The pressure required is only 350 bar, not 700 bar.
Posted by: H2O | 16 March 2006 at 04:17 PM
H20 -
I was not aware of the new adsorbant in the vehicle tank, though I had seen reports of research in that direction, e.g.
http://www.physicstoday.org/vol-57/iss-12/p39.html
You`re trading off crash safety and form factor options against the need to heat the tank to drive the hydrogen gas back out again.
Moreover, you will still have to transfer the fuel into that storage system as a gas at high pressure because otherwise the fuelling process simply takes too long. I don't think you'd want to do that inside your own home.
Posted by: Rafael Seidl | 16 March 2006 at 04:43 PM
If next generation Li ION batteries are put into mass production it would seem that vehicle hydrogen applications would be dead in the water. Current EV technology is more efficient and much cheaper than current FCV technologies. The ability to recharge a battery in 6 minutes is on par with the consumer's gas station experience. The only thing you need there is an outlet. I think pursueing hydrogen long term is a good idea but in the short to mid-term I don't see why we're not pursuing EV's. Most of the research has already been done. The costs are WAY lower and the infrastructure problem is non-existant. The storage concerns also seem much less daunting.
Posted by: Tripp | 16 March 2006 at 07:54 PM
"Honda is planning on building a production version of the FCX Concept. You can read about the FCX Concept here: http://world.honda.com/Tokyo2005/fcx/
"You can read about Honda's plans to produce it in production form in 2009-2010 here: http://world.honda.com/news/2006/4060108FCX/"
As with all fuel cell vehicles, the number of FCX Concept vehicles that Honda will actually build will depend almost entirely on how many ZEV credits the state of California is willing to hand out for the car. If the ARB chooses to be less than generous, don't expect to see more than a dozen FCX Concept vehicles in California...
Posted by: Jack Rosebro | 16 March 2006 at 10:48 PM
I don't suppose you have ever paid attention to Natural Gas costs during the winter have you? I admit I did not read everything in the home power generation unit Honda was mentioning but Natural Gas, though cleaner than other fossil fuels, still has many of the same issues inherent.
Electric would definitely be a better option...and in my mind the ultimate goal would be to have all electric vehicles eventually rather than all fuel cell vehicles. The metal constituents of batteries can be recycled and if the current research money and time put into fuel cells were instead put into furthering battery chemistry and controller/charger software and hardware EVs would easily be a worthy contender in a shorter time span then what will be required for fuel cell vehicles. Despite all of the efforts being put into fuel cell vehicles currently I feel that all of the present problems which need to be overcome will prove to leave fuel cell vehicles as just a footnote in the history of the automobile and another fad that came and went.
Posted by: Patrick | 17 March 2006 at 12:20 AM
It's instructive to note that a lot of automotive technologies, such as electric hybrids and four-valve cylinder heads were originlly invented over a century ago. It's quite possible that fuel cells will become a reality someday - but not before the cost (national security, economic, environmental) of hydrocarbons (fossil, biogenic) is considered unacceptable by a majority of the population.
Meanwhile, hybrids are one of the possible ways to limit hydrocarbon demand in the transportation sector. Wrt EV/PHEV concepts, note that fast-charging batteries *with high life expectancy* are still firmly in the laboratory stage. If they emerge into series production, they will require special high-power outlets. The regular ones in a US home are limited to 110V * 15 amps = 1650W with a dedicated circuit. Any more, and you blow a fuse.
Posted by: Rafael Seidl | 17 March 2006 at 01:14 AM
I am aware that at least one study suggests that a significant shift to a "hydrogen economy" may impact stratospheric ozone much like CFCs:
http://www.theozonehole.com/hydrogeneconomy.htm
One would think that this should be looked into more closely before we go too far down the hydrogen road!
Posted by: Carl | 17 March 2006 at 06:20 AM
Fuel Cells and Hydrogen are "Pie-in-the-Sky". Why does anyone spend research money on anything that has no potential for wide acceptance?
Politics (?)
Posted by: Lucas | 17 March 2006 at 08:43 AM
"rolling Hindenburgs"?? Good grief.
If you had a point, I missed it, since I stopped reading right there.
Posted by: John | 17 March 2006 at 05:06 PM
Hydrogen storage technology is not just for fuel cells anymore. HEC is offering modified auto engines that burn hydrogen, ammonia, or other fuels. Ammonia is a great, high energy density, and easily stored sustainable fuel (can be made from hydrogen obtained from water by electrolysis and from nitrogen from the air) but toxicity hinders widespead adoption. See the URL for information on storing ammonia in an easily handled form:
http://www.oregonbusiness.com/.docs/action/detail/rid/14956/pg/10003
thanks
Posted by: Bob | 03 June 2006 at 09:34 AM