Researchers at Pennsylvania State University (Penn State) have developed a process that converts polyethylene terephthalate (PET) plastic from beverage bottles into high-quality synthetic graphite, offering a potential new source of anode material for lithium-ion batteries.
The research, published in the journal Diamond and Related Materials, suggests the method could help address both plastic waste and the growing demand for battery-grade graphite.
PET Waste Converted Into Synthetic Graphite
The research team transformed shredded PET plastic into synthetic graphite by combining it with small amounts of graphene oxide and applying a controlled thermal process.
According to the researchers, the highest-quality graphite was produced using 2.5% graphene oxide, resulting in a more ordered crystal structure than commercially available natural graphite—a characteristic considered important for lithium-ion battery anodes.
Unlike conventional graphite production methods, the new process does not require metal catalysts such as iron, nickel, or cobalt. Eliminating these materials removes the need for additional purification steps to eliminate metal residues.
Lead author Shakshi Sekar said the process demonstrates that discarded plastic can become a valuable raw material.
“Most people think of a plastic bottle as waste once they’re done using it. Our work shows that the same material can become a valuable resource for producing graphite, which is essential for modern battery technologies.”
The researchers added that avoiding metal catalysts also reduces chemical usage during production and enables cleaner graphite manufacturing.
Supporting Future Battery Supply Chains
Graphite is one of the most important materials used in lithium-ion batteries, serving as the anode that stores and releases electrical energy.
Demand for battery-grade graphite continues to grow alongside the expansion of electric vehicles, stationary energy storage systems, and consumer electronics.
At the same time, PET remains one of the world’s most widely used plastics, with significant volumes still ending up as waste despite existing recycling programs.
Next Step Is Industrial Scale-Up
The researchers said the technology remains at the laboratory stage and further work is needed before commercial deployment.
Future research will focus on scaling the manufacturing process and evaluating how the synthetic graphite performs in complete lithium-ion battery cells.
If successfully commercialized, the process could provide a new recycling pathway that converts plastic waste into valuable battery materials while helping diversify graphite supply for the growing battery industry.