Researchers are making progress in developing rechargeable batteries based on potassium, a potential alternative to lithium that's less expensive and far more plentiful, and also have shown how to derive carbon for battery electrodes from old tires.
"With the growth of rechargeable batteries for electronic devices, electric vehicles and power grid applications, there has been growing concern about the sustainability and cost of lithium," said Vilas G. Pol, an associate professor in the Davidson School of Chemical Engineering at Purdue University. "In the last decade, there has been rapid progress in the investigation of metal-ion batteries beyond lithium, such as sodium and potassium."
Because of its greater abundance and lower cost, potassium shows promise for large-scale electricity storage on the power grid.
"The intermittent energy generated from solar and wind requires new energy storage systems for the grid," Pol said. "However, the limited global availability of lithium resources and high cost of extraction hinder the application of lithium-ion batteries for such large-scale energy storage. This demands alternative energy storage devices that are based on earth-abundant elements."
Potassium is about eight times more abundant than lithium and one-tenth the cost, he said.
Three research papers on the potassium-ion battery work were published this month, in collaborations with the U.S. Department of Energy's Oak Ridge National Laboratory and National Cheng Kung University in Taiwan.
"We initiated this program almost a year ago, and there are not many groups in the world working on potassium-ion batteries," Pol said.
The three papers were published in ACS Applied Materials and Interfaces, Chemical Communications and the Journal of the Electrochemical Society.