How Chemistry Impacts Hydrogen Fuel Cell Vehicles

[Last month] I had the privilege of attending the 246th American Chemical Society National Meeting and Exposition. This event provided an opportunity for chemists to collectively geek out about non-oxidative conversions, triazollium-based ionic liquids, and rhodium catalysts — for example — and for chemical supply companies to showcase contraptions that jostled, stirred, shook, rotated, inverted, injected, and swirled chemical compounds. This all made very little sense to me as a non-chemist, though I came close to purchasing a turbo vortex evaporator, just to say I own one, but please don’t ask me what it does.

What made sense to me as a transportation policy analyst, however, was the amazing potential of these studies and equipment to dynamically impact our transportation future, especially when it comes to hydrogen-powered fuel cell electric vehicles (FCEVs) — a technology that is a piece of our plan to cut projected U.S. oil use in half over the next 20 years.

What is a fuel cell vehicle?

Chemists Dr. Harry B. Gray and Dr. Clovis Linkous were two chemists I met at ACS who are researching the next breakthrough in the production and storage of hydrogen — a chemical that can power fuel cell electric vehicles (FCEVs). These vehicles are similar to battery electric vehicles (BEVs) like the Nissan LEAF in that they are powered exclusively by electricity. Unlike BEVs however, FCEVs are not recharged by plugging into the electricity grid. Instead, FCEVs use hydrogen to produce electricity via a fuel cell.

image via Hyundai

image via Hyundai

When a driver steps on the accelerator in a FCEV, hydrogen and oxygen are sent to the fuel cell, which produces both electricity that powers the motor and water as a byproduct. FCEVs, therefore, can be true zero-emission vehicles if the hydrogen fuel is produced the right way. Pure hydrogen gas does not naturally occur in concentrated amounts, meaning that it must be produced from sources such as water, natural gas, and coal.

How is hydrogen fuel produced?

The emissions associated with the production of hydrogen greatly varies depending on the particular process, which is why Dr. Gray and his “Solar Army” are working on a cost effective and zero emission way to use solar energy to convert water into hydrogen. During one of the major talks at the ACS meeting, Dr. Gray explained that one of the 21st century’s greatest scientific challenges is to find a cheap way to make sunlight a practical alternative to oil.

Enough sunlight falls on Earth in one hour to provide all of the world’s energy for an entire year, but no known stable material can efficiently and inexpensively utilize sunlight to convert water into hydrogen fuel. To solve this challenge, Dr. Gray has called upon hundreds of students and professionals to search for inexpensive catalysts that can absorb sunlight in a campaign that involves checking millions of combinations of the elements on the periodic table. This project allows students to hone their chemistry skills and methods, while helping solve one of today’s great energy dilemmas.

I prefer my hydrogen in pill form

One of the other remaining challenges for fuel cell vehicle developers is storing hydrogen onboard the vehicle. Because hydrogen is a gas, as opposed to a liquid fuel, a large volume of it is needed to travel the same distance as with a tank of gasoline. This means it is difficult to carry enough hydrogen on a vehicle to go very far. This problem may be solved, however, thanks to the research of Dr. Clovis Linkous at Youngstown State University. Dr. Linkous presented a paper at the ACS meeting that detailed his efforts to convert hydrogen into a solid state pill form that could allow FCEVs to carry enough hydrogen to greatly extend vehicle range.

Dr. Linkous’s “hydrogen on demand” system relies on using lithium borohydride (LiHB4) pills that react with water to generate hydrogen. Lithium borohydride stores hydrogen at a much denser rate compared to hydrogen gas, and just one gram of LiHB4 can liberate 4.11 liters of hydrogen gas at standard temperature and pressure. This means that FCEVs in the future could be “filling up” with pill packs of LiHB4 at a station near you.

Who’s producing fuel cell vehicles?

Of course, there are many steps between the research and development phase of this scientific research and the actual implementation of this technology in the real world. But the spread of FCEVs on our roads may happen sooner than you think. Toyota has been working on fuel cell technology with BMW and plans to unveil a new FCEV at the Toyko Auto Show in November. Hyundai will lease 1,000 hydrogen cars in the U.S. starting in 2015, and Renault and Nissan have partnered with Daimler and Ford to share the cost of developing FCEVs that could be on the market as soon as 2017. Honda will also launch a new generation of its FCEV called Clarity, which it has been leasing in limited numbers in California, by 2015.

With the advancement in FCEV technology and the willingness of automakers to produce these vehicles at scale, hydrogen is poised to be a fuel of the future that works in concert with a suite of other oil saving solutions, like biofuels and increased fuel efficiency, that can help us realize the benefits of a Half the Oil future.

union-scientistsEditor’s Note: EarthTechling is proud to repost this article courtesy of Union of Concerned Scientists. Author credit goes to Josh Goldman.

The Union of Concerned Scientists puts rigorous, independent science to work to solve our planet's most pressing problems. Joining with citizens across the country, we combine technical analysis and effective advocacy to create innovative, practical solutions for a healthy, safe, and sustainable future.