Keeping an Eye on Fuel Cell Operations:

A team of experts from a US national lab has developed a new type of observations method, called ambient-pressure photoelectron spectroscopy (APXPS), which helps them peer inside fuel cells.

Observing the individual components of fuel cells in action is no easy feat. A technique known as XPS can help scientists monitor them, but it only works in vacuum, whereas fuel cells need gases under pressure to function.

But investigators with a collaboration of American research institutes and universities have now developed the new method, which allows them to monitor every component and function of working solid oxide electrochemical cells.

The team features experts from the University of Maryland, the US Department of Energy’s (DOE) Sandia National Laboratories, and the DOE Lawrence Berkeley National Laboratory (Berkeley Lab).

Since fuel cells were invented, researchers understood that being able to measure the device's overall level of performance means nothing if individual components cannot have their performances measured as well.

With ambient-pressure XPS, this now becomes possible. The technology was successfully used in an environment heated to 750° Celsius (1,382 degrees Fahrenheit), and at a pressure of one millibar.

“Our team, led by Bryan Eichhorn of the Department of Chemistry and Biochemistry at the University of Maryland, combined the expertise in fuel cells at U Maryland, the experience of our Sandia Lab colleagues in collecting electrochemical data, and Berkeley Lab’s own development of a method for doing x-ray photoelectron spectroscopy in situ,” explains Zahid Hussain.

“Together we were able to measure the fundamental properties of a solid oxide fuel cell under realistic operating conditions,” adds the expert, who is based at Berkeley Lab's Advanced Light Source (ALS).

Details of the new investigation and its conclusions appear in the November issue of the esteemed scientific journal Nature Materials.

“What you need to know to improve any kind of fuel cell is where the inefficiencies are – places where energy is being lost compared to what theoretically should be possible,” ALS expert Michael Grass says.

“By scanning across the surface of the cell while it was operating, we could directly measure both the inefficiencies and the chemical states associated with them,” he concludes.

Source: Tudor Vieru, Softpedia