Graphite in a new form is the key to cheaper sodium-ion batteries.

The growing global demand for electric vehicles and renewable energy storage inevitably calls for the development of affordable, sustainable battery technologies. The latest research conducted by scientists at Rice University, supported by teams from Baylor University and the Indian Institute of Science Education and Research in Thiruvananthapuram, opens up a new perspective in anode design—one of the key components of batteries.

Graphite reimagined – not chemistry, but geometry
It has long been known that sodium and potassium—much cheaper and more abundant than lithium—could revolutionize the battery market. However, their larger atomic size has made it difficult to incorporate them into traditional graphite structures used in current lithium-ion batteries. New research suggests the solution might lie not in changing the material’s composition, but its shape.

The team of researchers developed innovative, purely graphite-based carbon structures in the form of microscopic cones and disks. These shapes are derived from by-products of the oil and gas industry through a scalable hydrocarbon pyrolysis process. Thanks to their curved morphology, these structures allow for effective intercalation (insertion) of sodium and potassium ions—without the need for chemical additives or complex modifications.

Breakthrough results: stability and performance
In laboratory tests, these materials demonstrated the ability to store about 230 mAh/g using sodium ions—and after 2,000 charging cycles, still maintained 151 mAh/g. For comparison, these results are on par with many commercial lithium-ion batteries, but achieved using much cheaper and more readily available raw materials.

Advanced imaging techniques confirmed that the material retains its shape even after thousands of cycles, and ions can easily enter and exit its structure. This is fundamental evidence that pure graphite—with the right geometry—can indeed work with sodium.

A sustainable battery future
The implications of this discovery are significant. It not only paves the way for the development of more affordable sodium- and potassium-ion batteries but also reduces dependence on lithium—a resource that is increasingly scarce and expensive, both economically and geopolitically. Equally important, the use of industrial waste in anode production aligns with the growing need for sustainable development.