Researchers at Penn State University, Pennsylvania, U.S., claim to have developed a process that converts PET plastic from beverage bottles into high-quality synthetic graphite. According to the researchers, the material could serve as an anode material for lithium-ion batteries in the future, simultaneously recycling plastic waste and meeting the demand for battery graphite.
A research team at Pennsylvania State University has developed a process to convert polyethylene terephthalate (PET) into synthetic graphite, and the process has now been published in the journal ‘Diamond and Related Materials’.
The scientists transformed PET into graphite using small quantities of graphene oxide and a controlled thermal process. According to the study, the resulting material exhibited a more ordered crystal structure than that of commercially available natural graphite, a key feature for use as an anode material in lithium-ion batteries.
Graphite is one of the most critical raw materials for lithium-ion batteries, serving as the anode material that stores and releases electrical charge. With the rising demand for electric vehicles, stationary energy storage systems, and consumer electronics, the need for battery-grade graphite is also increasing. Meanwhile, PET is one of the world’s most widely used plastics, much of which, despite existing recycling systems, remains unrecovered.
Optimal graphite
For their process, the researchers shredded PET plastic and mixed it with graphene oxide. The optimal graphite had a graphene oxide content of 2.5%. According to the team, this promotes the formation of ordered graphite crystals and, unlike conventional methods, eliminates the need for metal catalysts such as iron, nickel, or cobalt.
This also removes the additional purification steps required to eliminate metal residues. “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,” explains lead author Shakshi Sekar. By avoiding metal catalysts, the process also reduces chemical use, enabling the production of cleaner graphite.
“If waste plastic can become a feedstock for advanced energy materials, it changes how we think about recycling,” Sekar added. “Instead of viewing plastic as a disposal problem, we can see it as a resource that helps support clean energy technologies.”
Early stage
However, the research remains in its early stages. The scientists now aim to investigate how to scale the process for industrial applications and how the material performs in battery cells. If successful, PET waste could in the future be recycled and repurposed as a raw material for battery components.
While additional work is needed to evaluate large-scale production and battery performance, the study demonstrates a promising pathway for transforming one of the world’s most common waste streams into a high-value energy storage material.
This development aligns with the broader search for alternative raw material sources for battery production. Alongside efforts to expand graphite recycling, research institutions and companies worldwide are working to reduce the use of critical raw materials and utilize waste streams for battery manufacturing.
