Sand could hold key to longer smartphone battery life
Wed 9 Jul 2014
A new concept in battery technology that could outperform current designs by three times uses sand as a key material. Such a performance improvement could be highly significant for many users of small electronic devices such as smartphones whose power demands drain charge quickly.
Researchers at the University of California, Riverside’s Bourns College of Engineering have created the lithium ion battery that uses high quartz content sand on the anode rather than traditional graphite. The innovation is the brainchild of graduate student Zachary Favors.
“This is the holy grail – a low cost, non-toxic, environmentally friendly way to produce high performance lithium ion battery anodes,” he said
He has been working on lithium ion batteries mainly for use in personal electronics and electric vehicles. He is focused on the anode which has used traditionally graphite but that material’s performance has fail to keep up with the developments in electronics.
One possible solution has been to use silicon at the nanoscale instead but it degrades quickly and is hard to produce in large quantities.
From left, engineering professors Mihrimah Ozkan and Cengiz Ozkan with Zachary Favors in the Ozkan’s lab.
Favors has addressed these issue by using sand milled down to the nanometer scale and purified. He then added salt and magnesium and the resulting powder was then heated. “With the salt acting as a heat absorber, the magnesium worked to remove the oxygen from the quartz, resulting in pure silicon,” he said.
An added bonus was that the pure nano-silicon formed in a “very porous 3D silicon sponge-like consistency”. This porosity has proved to be the key to improving the performance.
Work now continues on producing the sand based silicon in larger quantities.