fuel cells and
battery-powered vehicles

subsidary to transportable fuels

a briefing document

On housing and making living systems ecological

Tectonics: tectonic plates - floating on the surface of a cauldron

Index
introduction
fuel cells
obtaining hydrogen
a prototype fuel cell car
some facts and figures
fuel cell technology
electric cars versus liquid fuel cars
battery technology

plug-in electric car with 250 miles range
tesla cars to sell home batteries

the economics and practicality of hybrid vehicles
battery materials - facts and figures
nanotech coming to lithium ion batteries
and now the beginnings of electric aircraft - who’s afraid of the end of filthy fossil fuels

coal to electricity better than coal to liquids
ultracapacitors

site map

advertising disclaimer

I am no vehicle mechanic, car buff or physicist. My interest is confined to the fossil fuel problems.

This subsidiary briefing document gives information on an example of a potentially non-fossil transportable fuel use. Fuel cell technology is also being increasingly used to provide small power plants for hospitals, hotels, precincts etc. This technology is scaleable.

Fuel cells

“The automobile industry of the late twentieth century is arguably the highest expression of the Iron Age. Complicated assemblages of some fifteen thousand parts, reliable across a vast range of conditions, and greatly improved in safety and cleanliness, cars now cost less per pound than a McDonald's Quarter Pounder. Yet the industry that makes them is overmature, and its central design concept is about to be overtaken.”
—
“The contemporary automobile, after a century of engineering, is embarrassingly inefficient: Of the energy in the fuel it consumes, at least 80 percent is lost, mainly in the engine's heat and exhaust, so that at most only 20 percent is actually used to turn the wheels. Of the resulting force, 95 percent moves the car, while only 5 percent moves the driver, in proportion to their respective weights. Five percent of 20 per-cent is one percent—not a gratifying result from American cars that burn their own weight in gasoline every year.
—
“Completely redesigning cars by reconfiguring three key design elements could save at least 70 to 80 percent of the fuel it currently uses, while making it safer, sportier, and more comfortable. These three changes are:

1. making the vehicle ultralight, with a weight two to three times less than that of steel cars;
2. making it ultra-low-drag, so it can slip through the air and roll along the road several times more easily; and
3. after steps 1 and 2 have cut by one-half to two-thirds the power needed to move the vehicle, making its propulsion system "hybrid-electric."

“In a hybrid-electric drive, the wheels are turned largely or wholly by one or more electric motors; but the electricity, rather than being stored in heavy batteries recharged by plugging into the utility grid when parked (as is true of battery-electric vehicles), is produced onboard from fuel as needed. This could be achieved in any of a wide range of ways: An electric generator could be driven by an efficient gasoline, diesel, Stirling (external-combustion) engine, or by a gas turbine. Alternatively the electricity could be made by a stack of fuel cells—solid-state, no-moving parts, no-combustion devices that silently, efficiently, and reliably turn hydrogen and air into electricity, hot [warm] water, and nothing else.”
Quoted from Natural Capitalism

“[...] the trend in energy use over the last one and a half centuries has been toward reduced carbon consumption and increased use of hydrogen. Each predominant feedstock - from wood, through coal, then oil, natural gas, and, ultimately perhaps, renewables - has contained more hydrogen and less carbon than its predecessor, and each successive fuel has been cleaner and more powerful.”
—
“Most industry is built on brute force: you start a process by increasing pressure or temperature. Nature changes free energy states much more gently, and, as a result, much more efficiently. So the next century is going to see a shift toward electrochemical processes and away from temperature and pressure systems." ” [Quoted from wired.com]

related material
Henry Ford, Ignorant Genius - Introduction | Henry Ford 1

obtaining hydrogen

Almost all hydrogen produced industrially at the moment is obtained by reforming fossil fuel - coal, oil and particularly gas. A considerable part of the optimism for fuel cell production is to reduce pollution, as a fuel cell combines hydrogen and oxygen to form water. The water is the exhaust, just as the vast variety of filth is the exhaust from the fossil fuel industry. As present routes to obtaining hydrogen involve fossil fuels, obviously much of the filth is still generated, although it does have the advantage of being more separated from people in large conurbations. Of course, cleaning and controlling pollution in one place is more efficient, as is processing materials on a large scale rather than in many small units. In this case, forming clean fuels from fossil fuels. That is, breaking down coal, oil or gas for hydrogen at a large industrial site is more efficient than breaking petrol or diesel down in car engines.

For the future, hope lies in the more direct route of producing hydrogen from water, either by electrolysis or by high-temperature disassociation. Thus, much cleaner technologies may be used, such as windmills and nuclear power. In a nuclear power station, only about 30% of the energy is used to produce electricity. Running a nuclear power plant at higher temperatures, more of the energy otherwise wasted can be utilised to produce hydrogen through heat disassociation of water.

Thus, a recent widely used cliché: The Stone Age did not end because we ran out of stones, nor will the Fossil Fuel Age end because we have run out of oil and coal.

A prototype fuel cell car

Looking forward along the ‘skateboard’ interior

Looking back along the ‘skateboard’interior

close-up of the fuel cell

close-up of the nickel metal hydride battery

some facts and figures

• Hydrogen storage cylinders made from aluminium surrounding carbon fibre
• Hydrogen stored at 350 bar/ 5,000 pounds per square inch (psi) pressure
• Each cylinder holds 1 kilogram of hydrogen
• Approximate driving range: 160 km
  This can be doubled with 700 bar tanks.
• The fuel cell can be regarded as a small-scale electric generator. When taken together with the hydrogen, the fuel cell and hydrogen may be regarded as a battery.
• Despite the fears, hydrogen is probably no more dangerous than petrol.
• Hydrogen for the fuel cell can be produced in a large number of ways. For example, by replacing the hydrogen cylinders with a ‘reforming’ plant which extracts the required hydrogen from petrol, methanol or whatever.

There many variations and hybrid versions of this type of technology, steadily moving from development towards production. The photographs and data above are from the prototype ‘F-Cell’ built on an A-class Mercedes frame. This prototype has advanced to the stage where at least seventy vehicles are on the road being beta-tested by selected drivers in everyday conditions. One of the test drivers is quoted as saying that the car reacts so quickly, that when getting away from traffic lights, he is ahead of sports cars for the first forty metres or so. He has to watch himself to avoid picking up traffic tickets.

Natural Capitalism
by Paul Hawken, Amory B. Lovins, L. Hunter Lovins

pbk : $11.67 [via amazon.com]
2000, Back Bay Books, 0316353000

hbk : $16.98 $16.98 [via amazon.com]
1999, Little,Brown, 0316353167
£16.14 [via amazon.co.uk]
2000, Earthscan Publications Ltd, 1853837636

fuel cell technology

Fuel cells are scalable and have a considerable range of potential applications - portable energy for electronic items such as lap tops, driving vehicles and local power plants.

The more efficient ones run on hydrogen, but transporting hydrogen has a variety of difficulties:

• it leaks easily through pipes,
• it has a relatively low energy density and requires compression or freezing to very low temperatures,
• pressure vessels to be secure add considerable weight.
• Hydrogen becomes liquid at -252.8°C / -423°F / 20°K. Hydrogen freezes at -259°C / 434°F / 14°K. It becomes a gas at -253°C / -423°F. All values are at 1 atmosphere / atmospheric pressure.

Therefore, reformers of various types are being developed (reformer: a device that strips out the hydrogen from the feed stock and supplies the hydrogen to the fuel cell).

For static power stations, the usual energy supply is in the form of ‘natural’ gas which can be piped, whereas for mobile units methanol is preferred.

Reformers often require expensive catalysts such as platinum.

There are problems with the life of both reformers and fuel cells [see also batteries]. Unsurprisingly, this is an area of intensive research.

“[..] the UltraCell product is different than other methanol fuel cells in that it converts methanol into pure hydrogen through it's revolutionary micro-reformer. Most portable fuel cell technologies are based on direct methanol fuel cell (DMFC) technology. The fundamental difference between the two is that DMFCs feed methanol directly to the individual cells, whereas the UltraCell RMFC technology employs its innovative micro fuel reformer to convert the methanol to hydrogen fuel and feeds that hydrogen to the individual cells. The UltraCell solution provides fuel cell stacks with twice the efficiency at half the size, while using ten times less precious metals than DMFCs.” [Quoted from ultracellpower.com]

Image credit: ultracellpower.com

Size: 150mm x 230mm x 43 mm / 6 inches x 9 inches x 1.7 inches Weight: 260 grams Output power: 10 - 25 watts This image is not full-scale. The unit is approximately the size of a standard hardback book.

electric cars versus liquid fuel cars

Electric cars are about four times as efficient as liquid fuel-driven cars, because liquid fuel converts most of the energy into heat. This disadvantage is offset by the greater energy density available in liquid fuels relative to battery technology.

The fuel cell technology discussed above is used to generate electricity onboard. Now we come to drives using rechargeable batteries. Such batteries can be used as buffers charged as above by fuel cells, or by small liquid fuel-driven motors. Or they can be used as assist and subsidary power to a liquid fuel engine.

As you will see, a large variety of drive systems are under competitive development. These batteries can also be topped up while off-road, from the electricity mains.

battery technology

As you may know from experience of car, laptop and other rechargeable batteries, the life expectancy of these devices is not wonderful. The large batteries (battery packs) used in electric cars can run to several thousand dollars. For example, this UK link quotes lightweight battery cars as running the equivalent of 600 miles on the price of a gallon of petrol. (Remember, petrol is more expensive in Europe - about twice the price in the USA.)

Increasingly, cities are giving special concessions to non-polluting cars. This can be a big consideration in a city like London with a £8-a-day congestion charge and horrendous parking fees. This has to be balanced against [also from the link]:

“Reliability: battery life for the G-Wiz is estimated at two to four years, depending on usage. The car is covered by a two-year warranty but if the battery fails outside that, it costs £1,200. Twike says its batteries will last for 50,000 miles, with a replacement cost of £3,180-£6,980”.

plug-in electric car with 250 miles range

If this lives up to expectations/claims this is considerable step forward to future transport - plug-in electric charging, 250 miles range and about 0-60mph in 4 seconds!

“63% of US oil use is for transport
“Electric power generation in the USA does not use oil. Coal, hydro, nuclear, solar, and natural gas are typical sources for generating electricity. Power generation plants, even coal burning ones, are inherently more efficient and less polluting than vehicles due to economies of scale and the ability to more efficiently remove pollutants from a smaller number of much larger fixed locations.

“Also, an electric car is far more efficient than a gasoline car, so the amount of pollution generated by producing the electricity to drive an EV a given distance is much less than the pollution from the gasoline to drive an internal combustion car the same distance.”

Driving will be much simpler with advanced braking and transmission.systems.

Estimated battery life - 500 complete discharge cycles.

“Driving only 50 miles is only a partial discharge, roughly using 20% of the charge. If a driver continues to drive 50 miles every day and recharges every night, then after 5 days they would complete the equivalent of one charge/discharge cycle.

“In estimating the life of our batteries, you can multiply the number of cycles by the range. Thus, 500 cycles times 250 miles/charge works out to 125,000 miles, but our estimate is a more conservative 100,000 miles. However the cycle life of 500 cycles is based upon performance that is more challenging to the battery cells than our application.

“A full charge using the home system can be achieved in as little as 3.5 hours.”

Charging is done either by using a professionally installed home charging unit, or by a portable unit, which is multi-voltage. The home charger runs at 70 amps/110 volts - this is a heavy current load, more than is required for an electric cooker, so users must ensure that their household electricity supply is not overloaded. Note that at lower amperages, for instance when using the portable charger, recharge times can be considerably longer.

The batteries will be seriously expensive to replace, so this price is difficult to come by, but see above for other battery prices.

100,000 miles of go juice in Europe will cost very roughly 10,000 euros or pounds, which is probably much more than a battery replacement cost; but more than the 1000 euros or pounds claimed for off-peak charging for the same distance. Guesses at a price for the new vehicle are currently around $100,000/£52,000, so buyers at this level are unlikely to jib at the low £1000s for battery replacement charges.

Doubtless, prices will steadily shrink as such vehicles and improved versions go into mass production. at some point this should lead to a paradigm shift. However, such expansion would result in massively expanded electricity generating requirements.

progress with batteries for hybrid vehicles

Batteries are steadily becoming lighter: lead > nickel > lithium.
[On the graph to the right, Wh/kg means Watt-hours per kilogram]

“Adapting the nickel-metal-hydride battery to the automotive environment was no small feat, since the way batteries have to work in hybrid cars is very different from the way they work in portable devices. Batteries in laptops and mobile phones are engineered to be discharged over the course of several hours or days, and they only need to last a couple of years. Hybrid-car batteries, on the other hand, are expected to work for eight to ten years and must endure hundreds of thousands of partial charge and discharge cycles as they absorb energy from regenerative braking or supply short bursts of power to aid in acceleration.”

tesla cars to sell home batteries for $3500

"Musk says the basic 10 kilowatt-hour Powerwall home system will sell for $3,500 and use much of the same technology found in Tesla electric cars, known for having the longest range per car of any pure electrics on the road. "In a lot of ways it's taking derivative technology from the car," he told reporters before the presentation.

"It's expected that the Powerwall would be bought mostly by homeowners who want to store energy from their solar systems, allowing them to run off their own power after the sun goes down. The company showed off the sleek design of the home batteries, pointing out they are a slim six inches thick and can be mounted on walls. He says he expects to have several of them mounted in his own home."
[Quoted from usatoday.com/]

Some question and answer data here.

the economics and practicality of hybrid vehicles

“A diesel hybrid can cut fuel consumption by a quarter versus a standard diesel. The challenge, PSA said a year ago, is to cut the cost difference between the two to 2,000 euros (US$2,600) or less from around 8,000 euros at the time.”
—
“For instance, fuel cell cars need to have an operating life of about 5,000 hours to compete effectively but at this stage only last around 2,000 hours, a DaimlerChrysler spokeswoman said.”

battery materials - facts and figures

• For similar power, a lithium-ion battery weighs around half the weight of a nickel-hydride battery. Lead, another metal used for batteries is even heavier.
• A hybrid car battery contains of some10 kilograms of nickel.
• Price of nickel: US$36,200 a tonne [June 2007].
• In 2006, the battery industry consumed 12,000 tonnes of lithium, which represents around a quarter of total output.
• Price of lithium: US$7,800-8,500 a tonne [June 2007].
• There is a huge supply of lithium in South America (mainly in Chile). Other unexploited sources suggested are North America and Russia.

nanotech coming to lithium ion batteries

“In the hybrid market, our product’s unique performance capabilities address power and cost barriers that currently limit HEV and PHEV adoption. In addition, A123Systems’ manufacturing model enables large volume production (millions of cells annually) at high quality and very competitive cost.

“A123Systems’ automotive class lithium ion[tm] technology uses proprietary Nanophosphate[tm] material that offers numerous unique features for hybrid applications, including unmatched power, abuse tolerance and life.” [Quoted from a123systems.com]

acronym

phev : plug-in hybrid electric vehicle.

application for using lithium-ion batteries containing nanophosphate

The Killacycle, the world’s fastest electric-powered drag bike

An electric motor-cycle that goes from 0-60 mph in 1.5 seconds.
• It goes to156 mph in 8.16 seconds.
• 990 A123Systems M1 [ANR26650M1] cells mounted in the bike.
  • Power output: over 350 horse power.
  • 900 cells make up a 375 volt, 7.5 kW-hr battery pack.
  • Battery pack gives1575 amps.
  • Powerpack weight: 161lb [73kg]
• Powered by 880, 2.3 amp-hr Lithium Ion cells made by A123Systems.
• Each 70 gram, 3.4 volt cells can put out over 150 amps
• Zilla 2K-HV motor controller (made by Cafe’ Electric) directs a 374 volt, 1350 amp flow of electricity from the battery pack to the twin electric motor.
  
  
• data sheet on the Killacycle.

  “...the KillaCycle is just a giant cordless drill with wheels.”

The manufacturers claim these batteries require much less oversizing by virtue of their reliability and power qualities.

Several such vehicles are now claiming into the 100mpg range equivalent, togrether with high acceleration and substantial ranges.

Plug-in electricity is far cheaper than highly taxed oil prices. 70% of USA drivers travel less than 40 miles per day. Battery prices are expected to fall considerably under mass production.

Then, it will become possible to charge batteries from photovoltaic arrays on your own property, thus privatising your fuel production.

Naturally, government will be displeased to see the vast taxes from oil and their centralised systems under threat.

This proposed British car will also run on nanotechnology lithium-ion batteries. However, in this case, the technology is based on nano-titanate materials from Altairnano [4-page .pdf], where as A123Systems uses nanophosphates.

The Altairnano .pdf is an excellent introduction to problems with standard lithium-ion batteries, and the much improved performance using a nano-titanate negative electrode, in place of the more common graphite cathode. For example:

“[...] This uncontrollable reaction [in standard lithium-ion batteries] is called a thermal runaway and ultimately leads to the destruction of the battery, and a resulting fire which could ignite the device to which the battery is connected such as an electric vehicle, laptop or cellphone.

“The initial increase in temperature could be caused by a number of problems including external shorting of the battery, internal shorting of the electrodes resulting from mechanical damage to the battery or a manufacturing defect, overcharging of the battery, electronic control unit failure or external heat. Impurities in the battery could be introduced during the manufacturing process ultimately leading to an internal shorting of the battery.”

and now the beginnings of electric aircraft - who’s afraid of the end of filthy fossil fuels

“ 'Hydrogen and fuel cell power technologies have now reached the point where they can be exploited to initiate a new era of propulsion systems for light aircraft and small commuter aircraft,' according to Professor Giulio.

“The advantages of deploying these technologies will be low noise and low emissions - features which are particularly important for commuter aeroplanes, which usually take off and land in urban areas.

“The possibility to take off and land without contravening the noise abatement regulations set for small airfields, in urban areas and near population centres, will allow the use of airfields late at night, when noise regulations are the most stringent.[Quoted from cordis.europa.eu]

“In an effort to develop environmentally progressive technologies for aerospace applications, Boeing [NYSE: BA] researchers and industry partners throughout Europe plan to conduct experimental flight tests this year of a manned airplane powered only by a fuel cell and lightweight batteries.

“The systems integration phase of the Fuel Cell Demonstrator Airplane research project, under way since 2003 at Boeing Research and Technology -- Europe (BR&TE), was completed recently. Thorough systems integration testing is now under way in preparation for upcoming ground and flight testing.

“ "Given the efficiency and environmental benefits of emerging fuel cell technology, Boeing wants to be on the forefront of developing and applying it to aerospace products," said Francisco Escarti, BR&TE managing director. "The Fuel Cell Demonstrator Airplane project is an important step in that direction." ” [Quoted from boeing.com]

coal to electricity better than coal to liquids

Meanwhile, a study suggesting coal to liquids is far less efficient and clean than coal to electricity, with or without sequestration, and thence plug-ins - that is, by replacing electric vehicles for ICEs (internal combustion engines).

“The Carnegie Mellon Electricity Industry Center (CEIC) has released a life cycle study [1] of prospective US transportation C02 emissions, comparing plug in hybrids to conventional ICE vehicles under a variety of coal energy input scenarios.” [Quoted from treehugger.com]

ultracapacitors - xavier

“Because no chemical reaction is involved, ultracapacitors—also known as supercapacitors and double-layer capacitors—are much more effective at rapid, regenerative energy storage than chemical batteries are. What's more, rechargeable batteries usually degrade within a few thousand charge-discharge cycles. In a given year, a light-rail vehicle might go through as many as 300 000 charging cycles, which is far more than a battery can handle. (Although flywheel energy-storage systems can be used to get around that difficulty, a heavy and complicated transmission system is needed to transfer the energy.)”
—
“Commercially available ultracapacitors [...] can provide many times the power of batteries of the same weight or size. But in terms of the amount of energy they can hold, ultracapacitors lag far behind. The major difference is that batteries store energy in the bulk of their material, whereas all forms of capacitors store energy only on the surface of a material. Like a battery, an ultracapacitor is filled with an ionic solution—an electrolyte—and its current collectors attach to the electrodes and conduct current to and from them. The collectors are coated with a thin film of activated carbon that has orders of magnitude more surface area than ordinary capacitors. The amount of surface area in ultracapacitor designs has so far been constrained by the limitations in the porosity of the activated carbon.”

This article, published in November 2007, is written by a team member at MIT’s Laboratory for Electromagnetic and Electronic Systems, who describes on-going improvements to ultracapacitors using nanotechnology.

“If my colleagues and I replaced the activated carbon with billions of nanotubes, we predicted we could make an ultracapacitor that could store at least 25 percent—and perhaps as much as 50 percent—of the energy in a chemical battery of equivalent weight.”

One of the goals is to be able to replace car batteries with ultracapacitor power.

“Even if it takes many years before ultracapacitors on their own can power either full battery-electric or hybrid cars, we're already at the point where such devices could easily assist lithium-ion batteries. When the car's electric motor needs high current for a short time, the ultracapacitor supplies it. After the demand eases, the ultracapacitor recharges from the battery, or the motor, working as a generator, or from regenerative braking.”

Other projected uses for ultracapacitors:

“Electric power grids could be 10 percent more efficient if there could be simple, inexpensive ways to store energy locally at the point of use.”

Update on ultracapacitors, used in eco-vehicles; March 2008

A better ultracapacitor requires more surface area. The addition of activated carbon coatings provides an porous and effective surface area that is 10,000 times greater than the materials previously used to gather ions. This is provided by replacing the porous activated carbon used in ultracapacitors with tightly bunched nanotubes. The ion-collecting surface area could be increased by as much as five. The addition of nanowires could bring the 5% storage capacity of current ultracapacitors up to 25 percent of the equivalent batteries. By increasing the voltage, the capacity could be doubled.

These inproved ultracapacitors can also be used in electric vehicles and hybrid cars because of the benefits of unlimited charge cycles and less overload-prone storage. [Précised from popularmechanics.com]

Plug-in hybrids, on the other hand, will probably still use batteries for their main battery pack, with capacitors for reclaiming energy while slowing down and to provide high-current acceleration. This will let the batteries discharge and recharge at moderate current, which should offer better performance and battery life over the long run. [Précised from popularmechanics.com]

Similar claims from this group have been around for more than 2 years, and should be treated with caution.

end note

1. This link goes to an abstract of this study. The full .pdf file is password-protected. A password is available from this linked page. The .pdf is also linked from this page.

email email_abelard [at] abelard.org

© abelard, 2006, 22 may

all rights reserved

the address for this document is https://www.abelard.org/briefings/fuel_cells_hydrogen.php

x words
prints as 7 A4 pages (on my printer and set-up)