LAKE WALES, Fl. — Today most fuel cells are recharged by stripping hydrogen from natural gas, a method that is efficient but requires fossil fuels. Fuel cells can also be recharged from electrolysis — splitting water into oxygen and hydrogen — but at a impossibly slow rate causing most applications to use natural gas.
Now, however, the Pacific Northwest National Laboratory (PNNL) has speeded up the hydrogen production process 1,000-times, enabling an electric vehicle fuel cell to be recharged in 90 second using water mixed with a protic ionic liquid that works similarly to the organic proteins in enzymes. The key to their discovery is a cheap nickel-based catalyst which performs the process speedup.
"The nickel catalyst is a molecular complex that is dissolved in the viscous liquid which is a protic ionic liquid," said PNNL's lead researcher on the project, chemist Molly O'Hagan, in an interview with EE Times. "Nickel is an abundant metal compared to platinum which is typically used as a catalyst for this transformation."
The Department of Energy's Pacific Northwest National Laboratory's master plan to eliminate the need for fossil fuels in the near future. (Source: PNNL)
The bad news is that it takes more energy input to produce the hydrogen fuel, when using nickel over platinum, however the good news is that the process can virtually synthesize hydrogen from cheap liquids in a fraction of the time previously required using the nickel catalyst.
"The catalyst uses electrons and protons to make the hydrogen fuel very quickly," O'Hagan told us.
Do not look for electric vehicles (EV) to start sporting 90 second recharge fuel cells just yet, however. O'Hagan does not even have a working prototype for EV makers. However, her team is working day and night to reduce the amount of energy required to power the catalyst induces the 90 second refuel goal, and sees no fundamental engineering impediments to prevent eventual success.
"Our fundamental research is focused on understanding how to reduce the energy input without losing the fast rates. We have found that controlling proton delivery is critical to fast rates without loss in energy efficiency. This fundamental understanding will then provide the tools to develop fast and efficient catalysts in the future," O'Hagan concluded.
Pacific Northwest National Laboratory chemist Molly O'Hagan explores different catalysts inspired by nature, looking for one that runs fast and efficiently to convert water to hydrogen fuel.
The hydrogen production rate today is 45 million molecules per second.
Yes it does use electricity, but instead of electrolysis, which is never mentioned in the article, a protic ionic liquid containing labile hydrogen is used with a nickel-based catalyst that spits off the hydrogen using electricity. It may sound like electrolysis, but is 1000 times faster, however uses more electricity than stripping hydrogen from natural gas. Their next step is to optimize the process to increase its efficiency so that it is better (or at least equal) to using fossil fuels (natural gas) in electricity consumption.
> what does it matter to the driver how long it takes to make the H2?
The faster, the cheaper the price at the pump, but the only way to do it quickly today is to use fossil fuels (natural gas).
The researchers point was that you no longer have to use natural gas to make hydrogen quickly. Electrolysis can make hydrogen from water, but is too slow to make it cheap at the pump. Their catalyst makes hydrogen fast. Next they aim to make it as efficient as natural gas, that is, fast and cheap.
Thanks; I tried to read the abstract, but it was very abstruse. I don't understand the basics here. Isn't the H2 for the fuel cell pumped into the car? If so, what does it matter to the driver how long it takes to make the H2? I don't care how long it takes to distill a gallon of gas. I only care how long it takes me to pump it into the tank.
This is far from commercial because of the low efficiency. As someone suggested, perhaps useful in a military context. The key problem is efficency. Heck, if you do not care about efficiency just burn the natural gas in a turbine. There are high temperature fuel cells which can reform NG and generate electricity at around 60% efficiency, and there are also combined turbine generator / district heating setups in that range too.
Gas is going to be disruptive for a decade or two. When the new Appalachian pipelines come on line it will complete the displacement of coal in the USA except for the open cast mines in the northern plains which consume locally and export electricity.
Natural gas vehicles have been around for decades. But during the decade or two which natural gas dominates we probably will see a continued rise of renewable electric, both for vehicles and increasingly on the grid. One of the values of gas is it is suitable for turbines and other generators which respond quickly. So it is a good partner for renewable until utility scale non-carbon storage is solved.
Oil is kept under control, but the big casualty has been and will continue to be coal.
Yes, there are many chanllenges infrastructure-wise. BMW and others have demonstrated hydrogen fueled cars they claim are safe, but this report does not address any of those issues, but merely shows a fast way to produce hydrogen without relying on fossil fuels (natural gas is the easiest fuel to convert to hydrogen).
Aside from the fuel cell catalyst mentioned in another comment, there is still the problem of transferring fuel to the vehicle and storing it. To me the main benefit of this faster hydrogen generation process is that fuel could be generated at service stations or home. But there are several challenges. First, due to limited electrical power, hydrogen would need to be generated and stored prior to refueling. Second, it is challenging to store hydrogen in a vehicle, currently using a very high pressure tank (5000 psi for Honda).
Electrolysis is relatively inefficient, especially since the oxygen is discarded. Hydrogen storage is inefficient due to the need to compress it to high pressure. I am not that keen to find out what happens when the tank is punctured in an accident. Consider what happened to Aubrey McClendon of Chesapeake Energy when his natural gas powered SUV crashed (or was crashed) into a bridge abutment. He probably died from direct crash injuries (no seat belt), but the fire burned everything up.