These results have just been verified by a team of researchers from the Bourns College of Engineering of the University of California which, using discarded glass bottles and subjected to a low-cost chemical process, have been able to extract pure silicon nanoparticles from their silicon dioxide to create high-performance lithium ion batteries.
"We started with a waste product heading to the landfill and have created batteries that store more energy, charge faster and are more stable than conventional ones."explains Changling Li, one of the participants in this research project led by professor of mechanical engineering Cengiz Ozkan, and professor of electrical engineering, Mihri Ozkan."Therefore, it is a very promising alternative for the next generation of lithium-ion batteries. "
As explained in a scientific article published in Nature Journal,silicon anodes replace graphite in these batteries. Although they are usually more unstable, researchers have solved the problem by reducing them to the nanoscale and combining large amounts of virtually pure silicon dioxide and inexpensive chemical reactions.
This process, which has allowed the research group to obtain lithium ion batteries that store four times more energy than graphite-based solutions, has been achieved in three steps: the first, consisting of reducing the glass bottles to fine powder; the second, a reduction that allowed them to transform silicon dioxide into nanostructures and, finally, the coating of these nanoparticles in carbon to improve their stability and their energy storage capacity.
Following this innovation,a single glass bottle can produce enough nano-silicon for three to five batteriescells or hundreds of button batteries. Thus, as argued by the researchers, these batteries could not only help to expand the range of electric and hybrid vehicles, but also allow to save energy in the charges of mobile phones and laptops.
However, the shrinkage that silicon undergoes during charging and discharging can make it unstable, but they have managed to reduce this problem by combining an abundant and relatively pure form of silicon dioxide with a low-cost chemical reaction. Thanks to this, it is possible to manufacture lithium-ion batteries with the power to store almost four times more energy than traditional graphite anodes.
Up to nine experts have participated in this project; The latest in a series pioneered by Cengiz and Mihri Ozkan to create lithium-ion anodes from environmentally friendly materials, something they had already tried with Portobella mushrooms, earth and diamoteas, a type of microalgae rich in fossils.
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