Battery
characteristics
(October 7, 2015) New
findings at Oregon State University have overturned a scientific dogma that
stood for decades, by showing that potassium can work with graphite in a
potassium-ion battery – a discovery that could pose a challenge and sustainable
alternative to the widely-used lithium-ion battery.
Lithium-ion batteries are ubiquitous in devices all over the
world, ranging from cell phones to laptop computers and electric cars. But
there may soon be a new type of battery based on materials that are far more
abundant and less costly.
A potassium-ion battery has been shown to be possible. And
the last time this possibility was explored was when Herbert Hoover was president,
the Great Depression was in full swing and the Charles Lindbergh baby
kidnapping was the big news story of the year – 1932.
“For decades, people have assumed that potassium couldn’t
work with graphite or other bulk carbon anodes in a battery,” said Xiulei
(David) Ji, the lead author of the study and an assistant professor of
chemistry in the College of Science at Oregon State University.
“That assumption is incorrect,” Ji said. “It’s really
shocking that no one ever reported on this issue for 83 years.”
The Journal of the American Chemical Society published the
findings from this discovery, which was supported by the U.S. Department of
Energy and done in collaboration with OSU researchers Zelang Jian and Wei Luo.
A patent is also pending on the new technology.
The findings are of considerable importance, researchers
say, because they open some new alternatives to batteries that can work with
well-established and inexpensive graphite as the anode, or high-energy
reservoir of electrons. Lithium can do that, as the charge carrier whose ions
migrate into the graphite and create an electrical current.
Aside from its ability to work well with a carbon anode,
however, lithium is quite rare, found in only 0.0017 percent, by weight, of the
Earth’s crust. Because of that it’s comparatively expensive, and it’s difficult
to recycle. Researchers have yet to duplicate its performance with less costly
and more readily available materials, such as sodium, magnesium, or potassium.