Six months ago, Zachary Favors, a graduate student at the University of California Riverside, was relaxing at the beach. He picked up a handful of sand and saw that it was primarily made up of quartz, or silicon dioxide. This led to a eureka moment.
The graduate student’s research is centered on improving performance in lithium ion batteries, which are primarily used for consumer electronics and electric vehicles. Specifically, Favors focuses on the negative side of the battery.
Currently graphite is the standard material used for the anode, or negative side, of the battery. However, as electronics have become more powerful, the ability to improve the graphite anode has reached its limit. Recent research has focused on replacing the graphite with nanoscale silicone. While this approach promises some improvements, it degrades quickly and is difficult to produce on a large scale.
Favors believed that ordinary sand might solve both of these problems. He looked for a spot where the sand contained a high concentration of quartz and found it, near his childhood home in Dallas, at Cedar Creek Reservoir. He ground the sand to a nanometer scale, purified it and added salt and magnesium, commonly found in sea water.
Favors, along with engineering professors Cengiz Ozkan and Mihri Ozkan, then tested the substance and were thrilled with the results. The researchers found that it not only worked, but the porous nature of the material provided significant improvements over the performance of standard batteries. The sand based batteries could expand the life of electric vehicle batteries three times or more. For cell phones and tablets it could mean only having to recharge the battery once every three days.
“This is the holy grail – a low cost, non-toxic, environmentally friendly way to produce high performance lithium ion battery anodes,” said Favors in a statement.
The researchers have published their findings in the paper “Scalable Synthesis of Nano-Silicon from Beach Sand for Long Cycle Life Li-ion Batteries,” in the journal Nature Scientific Reports and are now trying to produce larger quantities of the material.