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Making Fuel Cell Vehicles An [Almost] Affordable Reality

The first hydrogen-powered vehicles will go on sale next year, and they won’t cost $1 million, thanks to several key material breakthroughs

by Melody M. Bomgardner
November 17, 2014 | APPEARED IN VOLUME 92, ISSUE 46

California and Japan are places where the future arrives a bit early. And so it goes with the hydrogen economy. They are where hydrogen fuel stations are being built and where consumers will soon have the opportunity to purchase fuel-cell cars to use for personal transportation.

For a cool 7 million yen, or approximately $70,000, early adopters will be able to drive more than 400 miles on one fill-up of hydrogen and emit only water vapor.

H2 WHOA
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Credit: Toyota Motor
The Toyota FCV runs on hydrogen and emits only water vapor.
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Credit: Toyota Motor
The Toyota FCV runs on hydrogen and emits only water vapor.

Toyota Motor will be first out of the gate with its FCV model, which is expected to go on sale in April 2015 in Japan and in the summer of 2015 in California. Hyundai, General Motors, Honda, and Daimler all plan to offer fuel-cell vehicles for consumers in the near future.

Putting a fuel cell and hydrogen tank in a consumer sedan is the culmination of decades of research and development by automakers. GM powered its first hydrogen vehicle, called the Electrovan, in 1966 using fuel-cell technology borrowed from the space program. Toyota’s effort began in 1992, the same year it started developing the Prius gas-electric hybrid.

Serious consumer road testing began in 2007, when a small number of sports utility vehicles powered by fuel cells were introduced for lease. Back then, which is not so long ago, the SUVs cost about $1 million apiece.

A lot has happened since. The cost of fuel cells has come down, vehicle range has gone up, and performance goals, such as the ability to start up in frigid weather, have been met. Future hydrogen-powered drivers can thank innovations in chemistry and materials science for some of the most critical improvements, particularly inside the fuel cell itself.

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Credit: Ty Finocchiaro / Yang Ku / C&EN

Reaching the mass market still requires additional cost reductions of around 50%. And before fuel-cell cars can make a real impact on consumer transportation, infrastructure for hydrogen fuel stations must be built, and car buyers must switch to the technology in large numbers.

“I can’t say that the technology will become popular until at least 2025,” predicts Toru Hatano, an analyst at the consulting firm IHS Automotive. “As long as we can use other fuels—whether it’s gasoline, diesel, ethanol, or natural gas—consumers will not choose fuel-cell vehicles.”

Toyota and GM are taking different approaches to the adoption problem, while both firms actively work to make fuel cells less expensive. Toyota’s plan is focused on gaining consumer acceptance; it is even helping to finance the installment of hydrogen fuel stations. GM, for its part, has teamed up with Honda to make fuel-cell cars more cost-competitive.

The early generation of fuel-cell vehicles will compete with hybrid- and all-electric vehicles for the hearts and minds of low- or zero-emission car buyers. Although Toyota has had success with the Prius and other hybrid vehicles, it is now betting on a fuel-cell future, rather than an all-electric one.

“Battery-electric vehicles are limited in a lot of ways,” says Jana Hartline, environmental communications manager for Toyota Motor Sales U.S.A. The lithium-ion battery packs are too large and heavy to power efficient, convenient, and reliable vehicles. Future battery chemistries will make only an “incremental” difference, she argues. “Over the last decade, improvements in fuel-cell technology have lapped battery technology three or four times.”

Toyota points out that the convenience factor tilts heavily in favor of fuel-cell vehicles. The driving range is greater than what’s provided by all-electric and even many gas-powered vehicles. And a fill-up of hydrogen takes only three minutes, compared with overnight for a full battery charge in an all-electric car.

Since 2008, Toyota scientists and engineers have more than doubled the power density of the firm’s fuel cells. The smaller footprint means the automaker can fit a fuel cell under the seats of a regular-sized car, rather than under the hood of a hulking SUV. More strikingly, the cost of the fuel- cell system has been reduced by 95%.

The main reason for the cost breakthrough is a better catalyst that uses significantly less platinum. The catalyst enables a fuel cell to transform the energy in chemical bonds into electrical power. When hydrogen from a fuel tank flows to the anode side of the cell, it meets a platinum catalyst that splits it into two protons, leaving electrons that can be harnessed to both charge a vehicle battery and run an electric motor.

Like Toyota, GM has been busily removing platinum from its catalysts. In 2007, GM’s test model, called Project Driveway, used 80 g of platinum in its stack of fuel cells. “My workhorse system now is using below 30 g,” says Charles E. Freese, executive director of GM’s global fuel-cell activities. In development, Freese adds, is a stack that uses less than 10 g of the precious metal.

The secret has been to use much more surface and much less platinum to get the same catalytic power, Freese explains. It requires depositing a thin layer of catalyst on a carbon support structure. To further increase the surface area, GM is working on techniques including hollow-shelled metal particles and special layering of the atomic-scale shells. Alloys of platinum and cobalt are also being tested.

Not all of the combinations of surface modification and catalyst work in real-life conditions, Freese acknowledges. The carbon support may oxidize, and the platinum can migrate and form clumps, which changes its catalytic properties. “These things don’t go right by accident,” Freese says. The goal: a catalyst that maintains its activity over at least a 10-year, 150,000-mile vehicle life span.

Durability is also key to the performance of another important part of the fuel cell, the proton exchange membrane. The PEM conducts protons—the result of splitting hydrogen—from the anode side of the fuel cell to the cathode side.

DuPont has been making PEMs for fuel cells for more than 40 years. Its leading contender, called Nafion, is a sulfonated tetrafluoroethylene-based copolymer.

The membrane can shuttle protons only when it has absorbed water, explains Randy Perry, a principal investigator at DuPont. The addition of water makes Nafion ionic—it contains both positive and negative ions. The negative ions are attached to the membrane, whereas the positive ions are mobile. “They come in one side, and other protons go out the other side,” Perry says. In contrast, electrons don’t move well through water, so they stay behind.

One good way to make a fuel cell more powerful is to increase the number of protons that can move through the polymer membrane. And proton conductivity has improved dramatically since the late 1990s, thanks to experiment and design work conducted under actual driving conditions, according to Perry.

Matthias Gebert, product manager for fuel-cell membranes at chemical maker Solvay, says his firm likewise has made strides in maximizing the ion-exchange capability of its Aquivion fluoropolymer. Thinner structures have reduced raw material costs, he says, and composite blends with dedicated additives impart robustness. Further improvements are coming, Gebert adds, “but you will be surprised how the 2020 car will already be very much like what we are used to today.”

Back at Toyota, another material win was to store onboard hydrogen in a smaller space. The company is weaving its own carbon fiber tanks that compress the gas to 70 megapascals. The resulting 20% increase in density means the FCV model coming out next year will have only two tanks versus its predecessor’s four.

It may seem strange that automakers are doing so much of their own development work rather than outsourcing to suppliers such as Ballard Power Systems, a large fuel-cell maker. Indeed, each major automaker will likely spend around $5 billion on fuel-cell vehicle programs, estimates Cosmin Laslau, an analyst at Lux Research.

Cars are much different from the stationary generators for which many commercial fuel cells were designed. “The fuel-cell-making companies did not develop their products for automotive use but rather tried to adapt them for that use,” GM’s Freese explains. “But the requirements are very demanding; you can’t just take an off-the-shelf product and have it work without compromising the functionality of the vehicle.” Even purchasing raw materials is tricky, he adds. “You can get the very best of everything and get a very poor fuel cell.”

Currently, Ballard does not manufacture fuel cells for use in consumer automobiles. Instead, it lends its expertise to automakers via partnerships; Ballard has such an arrangement with Volkswagen, Laslau says.

It’s not clear when or if carmakers will see a return on their fuel-cell investments. “In the long term, the question is: ‘Are we really going to go away from combustion engines for serious environmental reasons?’ ” Laslau says. “In 20 to 40 years’ time, we might see the extinction of the combustion engine. But that’s fuzzy.”

In the near term, the new technology will do a great deal to help manufacturers meet fleetwide emissions reduction targets, particularly in California, which gives extra credit for long-range, zero-emission vehicles.

Crafting fuel-cell vehicles that suit the average consumer may take a decade or more, and Toyota, at least, is okay with that. “We’ve always been a much-longer-term-planning manufacturer,” Hartline says. “With the Prius, people told us we were insane, but 6 million units later, hybrids are now in every manufacturer’s lineup.”

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Comments
Tom Radecki (November 18, 2014 8:39 AM)
Fuel cells will be dead if the new advance in lithium ion battery technology of the titanium oxide nanotube anode pans out. It was recently announced by Nanyang University in Singapore by the same researcher who developed the current graphite anode. Recharging to 70% will only take 2 minutes and the batteries will last 1 million miles instead of 50,000 miles which means a 20-fold decrease in the battery cost per mile driven for a Nissan Leaf from 10 cents to 0.5 cents. Instead of replacing the battery every 50,000 miles, you'll replace the vehicle every 200,000 miles.

The new battery technology has already been commercialized and is projected to be on the market in 2 years. With buried induction coil charging, drivers won't even have to get out of their cars. Charging stations can be simple parking spaces along the road way. The cost of electricity is half as much as hydrogen. And consumers who already have electric cars give them very high consumer satisfaction ratings according to Consumer Reports.

Consumers like not having to go to gas stations and like charging at home. Even with pure coal electricity, a Nissan Leaf is cleaner than a Prism hybrid. It gets 3.3 miles per kWh and coal electricity is 1# of CO2 per kWh while gasoline is 25# per gallon when including the footprint of production. Assuming that the scientist knows what he is doing, and it sounds like he does, gas stations and hydrogen stations are very likely to die out in the next decade because electricity is so much cheaper than gasoline. 90% of electric energy goes into moving the car forward vs 25% of gasoline energy with the rest just wasted heat. People will charge up at home, at work, and along the roadside in just 2 minutes. No messing with stinky gasoline or explosive hydrogen.
Ben (November 20, 2014 4:54 PM)
Improving charge times will help, as well as durability, what will the energy density improve much? Will you ever have a 500 mile range in an EV? Not based on CEN's previous review of targets for Li/air batteries.
A.Chandrasekaran (November 26, 2014 11:25 AM)
But if charging is at least as fast as filling gas/petrol, then there is no need to go 500 mile at one charge. It looks like this will meet that easily. If it works, it reduces lot of distribution network development costs too. It simplifies a lot, but simplicity may be bad for economy!
But, I will be somewhat uncomfortable sitting on strong induction coils, until more is known. I will prefer stretching my legs out while charging! Hope it lives up.
Jono (December 18, 2014 5:46 PM)
Tom, believe those battery promises when you see them in a commercial product. But you'll be waiting a long time...
Jay Spivack (November 19, 2014 2:48 PM)
Of course, the environmental impact will depend on the source of the H2. If we continue to use methane reforming we might as well burn methane in the car. If we go to PV, wind, or hydro driven electrolysis then I wonder how much it will take to drive the entire US fleet of cars. Does anyone who reads this know what area of solar panels it would take to power a fuel cell car for a typical driver (say 15000 miles per yr)?
Gerald Ceasar (November 20, 2014 6:05 PM)
@ Jay Spiva, the problem with combusting methane is that engines in conventional cars are Carnot Heat engines that are limited by the Laws of Thermodynmaics and are terribly inefficient in combusting the methane and then providing that energy to the wheels with all the pistons and drive converters. It's well under 20% in conversion of methane energy to the wheels. Electric motors used in EVs and FCs EVs provide torque directly to the wheel and are much more energy efficient than any conventional car that is limited by the Carnot cycle.
Jono (December 18, 2014 5:44 PM)
I don't see people saying we shouldn't use EVs because the majority of our grid electricity currently comes from fossil fuels. Hydrogen can be made from as many sources of energy as electricity can (solar, wind, nuclear, landfill gas, waste water treatment plants, chemical plants, etc.). Just because the current dominant source is methane, doesn't mean it will always be. Plus there are many benefits to converting methane to hydrogen and using a fuel cell rather than using the methane directly. Ever think that methane is at least a 20 times more potent GHG than CO2? And you want to increase distribution and storage, thus leaks, of methane? Converting methane as quickly as possible after it comes out of the ground has huge environmental benefits.
Gerald Ceasar (November 20, 2014 5:35 PM)
Fuel cells like those from Plug Power are being used today to power emission free fork trucks in many warehouses. They have an advantage over electric fork trucks whose battery pack need to be recharged overnight.

It is too bad that on-board reforming of methanol to H2 has not proven to be cost, performance and volume effective for FC vehicles. This would have overcome the expensive need for a costly new gaseous H2 refueling infrastructure.Demonstration FC cars have been around since the late 1990s and I remember test driving those from Toyota and Daimler Benz at FC meetings here.They drove like today's cars.

There was even a car that supposedly ran on water that I test drove around the Pennslvania State capital in Harrisberg while being BP America's Man on Electrical Vehicles in the early 1990s. The inventor of this car whom I will leave nameless claimed he had made a FC car where the PEM FC in one cycle could run in reverse generating hydrogen that was then stored as a compact solid metal hydrogen material. On heating slightly the metal hydride yielded H2 which then served as a fuel for the FC when it ran in the forward direction. All I remembered then is that this car had a big battery pack and a very small FC engine. The British Press had a field day with articles in the Telegraph about the car that ran on H2O and its impact on BP.
A.Chandrasekaran (November 26, 2014 11:44 AM)
If the battery cost comes down, just a couple of extra batteries can be kept for charging and replacing when needed, instead of charging while in the vehicle. They should standardize the batteries like many inter-changeable things we have and also place it in a easy to change way, cartridge style. It will get there, if not already.

Tom Radecki here was talking about much faster charging batteries coming up as well.

By the way, if someone explained that running something in forward and reverse cycle both generated energy, that is reason enough for a chuckle and a walk/run.
Jono (December 18, 2014 5:37 PM)
That's what they do today, which is why fuel cells are so much cheaper to operate that battery forklifts. Fuel cells may be expensive, but they're still cheaper than 3 battery packs. Plus, the forklifts are much more productive because it takes less time to refill with hydrogen than it does to swap out the battery packs.
Melody Bomgardner (November 21, 2014 5:28 PM)
Thanks for the great comments. Definitely a step change in charging/time and range (power density) for EVs would give FCVs a run for their money. Electrolyser-made hydrogen would likely be made from off-peak solar and wind power, thus somewhat side stepping the "how many panels would it take" question. Natural gas vehicles are quite popular for some applications, just like fuel cell forklifts have really taken off. How about a fuel cell powered locomotive? And yes, it is true that materials like proton exchange membranes are used also inside of electrolysers (that make hydrogen fuel). It's almost, but not quite, like a fuel cell turned upside down (backwards?).
Kendal Ryter (November 24, 2014 12:30 PM)
We need to think about where the electricity to recharge the electric vehicle comes from. It comes from the grid and mostly coal fired power plants. This is not sustainable. We need to change the infrastructure and our wqays of thinking about public transportation if we really want to address the issues facing us in the very near future when "cheap" fossil fuels go away. All of the current fuel sources (generating H2 and electricity) require MUCH more energy to produce than they give in return. In the end this determine which technology wins.
A.Chandrasekaran (November 26, 2014 11:31 AM)
I agree. But still it is easier to control/manage few power generating points than millions of vehicles and others.

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