Published on July 14th, 2014 | by James Ayre10
Lithium Ion Batteries Get Big Performance Boost From Wonder Material Known As… Sand
July 14th, 2014 by James Ayre
A new lithium ion battery that notably outperforms the industry standard across a wide variety of different parameters was recently created by researchers at the University of California, Riverside’s Bourns College of Engineering, through the use of a new “wonder material.”
The new wonder material is, of course… sand. Yes. Just sand. Nothing else.
“This is the holy grail — a low cost, non-toxic, environmentally friendly way to produce high performance lithium ion battery anodes,” states Zachary Favors, a graduate student working with Cengiz and Mihri Ozkan, both engineering professors at UC Riverside.
The idea came to Favors, very unsurprisingly, while he was hanging out at the beach. The exact moment was when “he picked up some sand, took a close look at it and saw it was made up primarily of quartz, or silicon dioxide. ” That’s certainly a Eureka moment right there isn’t it?
Most commercial battery anodes currently in use (the industry standard) are composed of graphite. The material certainly works well but its limits have more or less been hit. As a result, researchers are currently exploring substitutes, of which silicon at the nanoscale is one.
There’s an issue with it, though: it degrades relatively quickly and it’s hard to produce cheaply in large amounts. That’s where the new work comes in.
The press release from UC Riverside provides more:
Favors set out to solve both these problems. He researched sand to find a spot in the United States where it is found with a high percentage of quartz. That took him to the Cedar Creek Reservoir, east of Dallas, where he grew up. Sand in hand, he came back to the lab at UC Riverside and milled it down to the nanometer scale, followed by a series of purification steps changing its color from brown to bright white, similar in color and texture to powdered sugar.
After that, he ground salt and magnesium, both very common elements found dissolved in sea water into the purified quartz. 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.
The Ozkan team was pleased with how the process went. And they also encountered an added positive surprise. The pure nano-silicon formed in a very porous 3-D silicon sponge like consistency. That porosity has proved to be the key to improving the performance of the batteries built with the nano-silicon.
Via the improved performance, the researchers think that the lifespan of silicon-based electric vehicle batteries could be increased by as much as 300% or more. Of course until such claims have been demonstrated, it’s always worth taking them with a grain of salt (no pun intended).
The researchers are currently working to produce larger quantities of the nano-silicon beach sand, and will then begin working with larger battery designs — moving from coin-size batteries to pouch-size batteries, like those used in cell phones.
Patents have already been filed for the new technologies.