Eggshells for Energy Storage

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7 December 2012—Owners of electric cars may soon be driving on eggshells, if David Mitlin has anything to say about it.
Mitlin, a professor of chemical and materials engineering at the University of Alberta, in Edmonton, Canada, is working on a way to turn waste eggshell membranes and egg whites into materials for high-performance supercapacitors. Supercapacitors offer high power density, charging and discharging far faster than rechargeable batteries. Unfortunately, they store much less energy. Mitlin thinks the membranes inside eggshells could help crack that problem.
“If you could keep the very nice power of a supercap but extend the energy density even to be that of a mediocre lithium-ion battery, you’d really enable the applications world in the automotive sector and in consumer products,” Mitlin told attendees at the Materials Research Society’s Fall Meeting in Boston last week.
Supercapacitors are electrochemical devices that store a double layer of charge on activated carbon as electrodes. Mitlin and postdoctoral fellow Zhi Li propose replacing the activated carbon with eggshell membranes from certain industrial chicken farms. These farms provide eggs yolks for the production of medicine and cosmetics but discard the shells.

Source:IEEE