Graphite is the most widely used material for the anode (negative electrode) in commercial lithium-ion batteries. It’s a form of carbon with a layered structure, which allows lithium ions to intercalate (insert) between its layers during charging and then de-intercalate during discharging. Graphite can be generated synthetically through modification of carbon precursors or obtained through mining of natural resources. A fully lithiated graphite (often written as LiC₆) can host one lithium atom for every six carbon atoms, corresponding to a theoretical specific capacity of about 372 mAh/g. Graphite is popular because it has a good balance of properties: it’s relatively abundant and low-cost, it has a reasonably high energy density, good cycling stability, and a low operating voltage (~0.1 V vs. Li/Li⁺ at full charge). However, graphite isn’t perfect – fast charging at low temperature can cause lithium plating which must be managed, and is limited in ultimate energy density.
NOVONIX has deep expertise in graphite, both in producing synthetic graphite for battery use and in testing graphite anodes. NOVONIX’s anode material is an example of a high-performance synthetic graphite tailored to meet the requirements of battery producers. In testing labs, NOVONIX evaluates how different graphites (natural vs synthetic, various particle sizes and shapes, different coatings or additives) perform in terms of rate capability, first-cycle efficiency, and cycle life. They also study how graphite interacts with electrolytes – the formation of the SEI (solid electrolyte interphase) on graphite is critical for battery stability. By experimenting with electrolyte additives, NOVONIX works to improve the SEI on graphite, reducing capacity loss and enhancing safety. Additionally, NOVONIX tests blends of graphite with other materials like silicon to boost energy density while leveraging graphite’s stable cycling. Graphite will likely remain a cornerstone of lithium-ion batteries for the foreseeable future, and NOVONIX’s research ensures it continues to improve.
