March 2, 2009
Recycled newspapers store electricity
used newspapers a bath in the right chemicals and you get a green
twofer: cheap ultracapacitor electrodes for storing electricity and
a new use for recycled newspaper.
Putting used newspaper in a solution of potassium hydroxide
yields highly porous, or activated, carbon that works as an ultracapacitor
electrode. The carbon material has a surface area of 416 square meters
per gram, which is close to the surface area of commercially available
The waste paper carbon stores 180 farads of electrical charge
per gram. Commercial activated carbons typically store 100 to 300
farads per gram depending on electrolyte type and voltage level.
Inexpensive precursor materials for activated carbon promise
to reduce the cost of ultracapacitors. Lower-cost ultracapacitors,
in turn, promise to reduce the cost of hybrid and electric vehicles,
and make it more practical to store electricity generated by renewable
but intermittent sources like wind turbines and solar cells.
Waste Paper—A New Source of Raw Material for Electric Double-Layer
Journal of Power Sources, published online January 30, 2009
Related stories and briefs:
paper combo promises light batteries -- related research
Back to ERN
March 9, 2009
Energy-related books and products