A team of researchers at the University of California, Riverside developed a low-cost way of turning recycled glass bottles into lithium-ion batteries that store almost four times more energy than traditional ones. Besides they’re environmentally friendly, they can last much longer than conventional batteries. This finding may be particularly appealing to mobile users given that the battery life is one of the main issues.

Glass products are 100 percent recyclable, and recycled glass is one of the most reused materials on earth. Yet, there are still billions of waste bottles that end up in landfill sites. Researchers have figured out that they could use silicon dioxide in these glass bottles. The reason why they wanted to use silicon is the fact that silicon anodes are capable of storing more energy than carbon ones.

However, silicon anode has its own flaws, such as expansion and shrinkage during charge and discharge which can make them unstable. So, the researchers overcame the problem by reducing the size of silicon particles to the nanoscale.

To create the anodes, the team used a three-step process. First, the bottles are crushed and ground down into a fine, white powder. Next, the silicon dioxide is reduced down into nanostructured silicon with the help of hot magnesium. Finally, those nanoparticles are coated in carbon, which makes them more stable and improves their energy storage capacity.

Waste glass bottles are turned into nano silicon anodes using a low-cost chemical process. Image Credit: University of California Riverside

According to lab test, coin cell batteries that were made using the glass bottle-based silicon anodes considerably outperformed conventional batteries and demonstrated excellent electrochemical performance.

We started with a waste product that was headed for the landfill and created batteries that stored more energy, charged faster, and were more stable than commercial coin cell batteries. Hence, we have very promising candidates for next-generation lithium-ion batteries, says Changling Li, lead author on the study.

Researchers noted that one glass bottle provides enough nano silicon for hundreds of coin cell batteries, or three-five pouch cell batteries. Also, they have filed a patent to eventually commercialize the batteries.