Science

Harvard scientists create hydrogen fuel cell that lasts longer

Harvard scientists create hydrogen fuel cell that lasts longer
Harvard researchers have developed a solid-oxide fuel cell that doubles as a battery
Harvard researchers have developed a solid-oxide fuel cell that doubles as a battery
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The tiny fuel cells are the dark specks within the nine white circles
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The tiny fuel cells are the dark specks within the nine white circles
Harvard researchers have developed a solid-oxide fuel cell that doubles as a battery
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Harvard researchers have developed a solid-oxide fuel cell that doubles as a battery

Materials scientists at Harvard have created a fuel cell that not only produces energy but also stores it, opening up new possibilities in hydrogen fuel cell technologies. The solid-oxide fuel cell (SOFC) converts hydrogen into electricity, and could have an impact on small-scale portable energy applications.

The thin-film SOFC benefited from recent advances in low-temperature operations, which enabled the integration of versatile materials, said lead researcher Shriram Ramantham. The star of the new cell is vanadium oxide, a multifuncional material that allows the fuel cell to multitask as both an energy generator and storage medium.

The new fuel cell uses a bilayer of platinum and vanadium oxide for the anode, which allows the cell to continue operating without fuel for up to 14 times as long as the thin-film SOFCs that use platinum only for the electrodes. In the case of the latter, when the platinum-anode SOFC runs out of fuel, it will continue to generate power for only about 15 seconds before it fizzles out. With the new fuel cell, the scientists have managed to increase that to three minutes, 30 seconds at a current density of 0.2 mA/cm2.

That length of time could be increased with further improvements to the composition of the vanadium oxide-platinum anode. It should happen fairly soon, and this type of fuel cell could be available for applications testing within two years. The researchers say that one field that could benefit from the new fuel cell is micro aerial vehicles, although fuel cells for powering vehicles are already a reality.

The researchers observed and confirmed a few chemical phenomena that possibly explains the extended power of the cell. The first of these is the oxidation of the vanadium ions. Another one is the storage of hydrogen within the vanadium oxide crystal lattice, which is then gradually released and oxidized at the anode. Finally, they noticed that the concentration of oxygen ions differs from the anode to the cathode, which could mean oxygen anions (negatively-charged ions) also get oxidized as in a concentration cell.

Details about the research appeared in the journal Nano Letters.

Source: Harvard University

3 comments
3 comments
David Anderton
The only problem they haven't fixed is that the fuel cell still contains platinum which as we all know is extremely expensive.
MQ
They did invent batteries a while ago.... We also have super-capacitors....
Sure we can keep making improvements, but why the wait....
Get systems on the streets and into people's homes...
I haven't seen a useful practical hydrogen fuel cell anywhere....
These things were invented something like (can't be bothered to check right now) 60 years ago, that is a hell of a long development time, don't tell me it is because it is complicated, or there is platinum and rare earths in it, yeh, that is also true of Computer chips... and look how fast they hit the road..
Fir example... We had electric city cars in 1900.... with today's variable frequency AC and brushless DC motors, with the great battery tech we have, what the hell is wrong with the regulators, and moto co's. oh I know it is all vested interests...
Regulators could cut the smog inducing commute tomorrow (at the risk of a few unhappy people) Any petroileum (sic) car (or cars registered to one person) which is/are in the CBD more than 2x in a week, MUST pay a congestion tax for every day they enter the CBD (or surrounds) Occasional users, (say my granny (who is now dead) needs to go to the Dr once and shopping once gets to not pay the tax..) either pay no congestion charge, or a reduced rate (out of peak) or better still park and ride on a free bus.. Solution, people buy an electric car for the commute, and manufacturers will supply a much better one than they currently do, if there is a proven market... It has to be cheaper to have a City car and a Weekend car than pay a crippling Congestion charge...