Researchers at the University of California, Riverside have made a big development in renewable energy. They have used waste glass bottles and a cheap chemical process to create the next generation of lithium-ion battery. The glass is used to create nano silicon anodes that are needed in lithium-ion batteries. These new batteries will provide more power and battery life to electric and plug-in hybrid vehicles and personal electronics. Cengiz Ozkan and Mihiri Ozkan, two professors at Riverside, are leading the project.
There are billions of glass bottles that end up sitting in landfills every year. Knowing this, the researchers wondered if the silicon dioxide that is in waste beverage bottles could be utilized for high-purity silicon nanoparticles for lithium-ion batteries.
Waste glass bottles are turned into nanosilicon anodes using a low cost chemical process. (Source: University of California, Riverside)
Silicon anodes have their positives and negatives. They can store up to 10 times more energy than conventional graphite anodes. But they expand and shrink during charge, which makes them unstable. It has been discovered that downsizing the silicon to nanoscale has reduced their instability. By combining a relatively pure form of silicon dioxide, like the ones taken from glass waste bottles, and a chemical reaction, the researchers created the lithium ion batteries. These batteries store four times more energy than conventional anodes.
To create the batteries, the glass bottles are crushed and ground into a fine white powder, a magnesiothermic reduction which transforms the silicon dioxide into nanostructured silicon. They then coat the silicon nanoparticles with carbon, which improves their stability and energy storage.
The coin cell batteries that have the glass bottle based silicon anodes outperformed traditional batteries in lab tests. The glass derived silicon electrodes demonstrated excellent electrochemical performance. They had a capacity of about 1,420 milliamp hours per gram with a C-rate of C/2 rate after 400 cycles. Researchers say that one glass bottle provides enough nano silicon for hundreds of coin cell batteries.
The paper titled, “Silicon Derived from Glass Bottles as Anode Materials for Lithium Ion Full Cell Batteries” was published in Scientific Reports.
