As electric vehicles and renewable energy systems become more common, the world is searching for better, more affordable, and environmentally friendly battery options.
A new study from Rice University and its partners may provide a major breakthrough by using carbon in a brand-new shape to build better batteries.
Published in Advanced Functional Materials, the research explores using carbon structures shaped like tiny cones and discs—created from waste materials from the oil and gas industry—as an alternative to traditional battery components.
These shapes show great promise for making sodium-ion batteries, which are cheaper and more sustainable than the popular lithium-ion batteries we use today.
Lithium-ion batteries rely on graphite to store and move energy.
However, graphite doesn’t work well with larger, cheaper elements like sodium or potassium. Their atoms are too big to fit into the tight layers of graphite.
Scientists have been trying for years to find a carbon material that can handle these larger ions without needing to change the chemistry too much.
The research team, led by Professor Pulickel Ajayan from Rice University, discovered that by reshaping carbon at the microscopic level, they could solve the problem.
These new cone and disc-shaped carbon materials allow sodium ions to enter and exit easily, without needing chemical additives or treatments. Even more impressive, the material stays strong after thousands of charge and discharge cycles.
In lab tests, the cone and disc carbon stored 230 milliamp-hours of charge per gram using sodium ions. After 2,000 fast charging cycles, it still held 151 mAh/g. These results suggest the material is highly durable. The team also tested it with potassium-ion batteries, with slightly lower performance.
The scientists used powerful tools like cryogenic electron microscopes and nuclear magnetic resonance to confirm that the ions were moving correctly through the material and that the carbon shape remained stable over time. This is one of the first clear demonstrations that pure graphite-like carbon, without any added elements, can work well with sodium.
This discovery could help reduce our dependence on lithium, which is getting more expensive and harder to source due to political and environmental concerns. Since the cone and disc carbon can be made from industry waste, it’s also a more sustainable option.
Rather than changing the chemistry, this study shows that changing the shape of materials can open up new possibilities in battery design—making cleaner, cheaper energy storage a reality for more people.
