Researchers have developed carbon fibers to form electrodes that outperform conventional graphite electrodes. The remarkable thing about these electrodes is that the carbon fibers are derived from wild mushrooms. The fibers are modified with cobalt oxide nanofibers.
The fungus used is Tyromyces fissilis. The fungus is a common plant pathogen, found in North America. The fungus is not edible and it appears white, cream or yellowish.
The reason for using the fungus as the basis of a battery electrode was to improve battery performance. Modern devices are very power dependent and a technological hunt is on for better energy density and power output. This is particularly important should electric vehicles take off.
The combination of the carbon derived from the fungus and cobalt oxide nanofibers had a synergistic effect, leading to improved power output. The so-called hybrid battery achieved a stable capacity of 530 milliamp hours per gram in tests. This was 150 percent better than equivalent graphite based battery. The attachment of the nanofibers led to an increased storage of lithium during recharging.
A battery works by having two electrodes. One is called an anode and the other a cathode. Lithium ions are stored in the anode during recharging and it is with improving the performance at this stage that much research is centered on. The reason for selecting the Tyromyces fissilis fungus is because is abundant with suitable fibers, and, geometrically the fibers are in a natural shape that helps with conductivity.
Lead researcher, Professor Vilas Pol told Controlled Environments magazine that
“Both the carbon fibers and cobalt oxide particles are electrochemically active, so your capacity number goes higher because they both participate.”
The study was carried out at Purdue University. The research is published in the journal Sustainable Chemistry & Engineering. The research is titled “Wild Fungus Derived Carbon Fibers and Hybrids as Anodes for Lithium-Ion Batteries.”