Graphite is a naturally occurring form of crystalline carbon with its atoms arranged in a hexagonal structure. It is a native element mineral found in metamorphic and igneous rocks.
Graphite has several commercially valuable properties:
Highest natural strength of any material
One of the lightest of all reinforcing agents
Extreme resistance to heat (maintaining its strength and stability to temperatures above 3,600 C)
Nearly chemically inert in contact with almost any other material
Until recently, the largest demand for graphite has come from the steel industry where it is used for crucibles and other refractory purposes. Other traditional applications include automotive components, inks and coatings, paints, polymers and plastics, lubricants and grease, ceramics, drilling fluids, steel pipe and tubing, fire retardants and oil spill recovery materials. However, the material’s high conductivity also makes it useful in electronic products such as electrodes, solar panels, and most notably batteries.
Not all graphite is created equal and there can be considerable variation in natural purity and other characteristics such as flake size. The mineral’s inherent characteristics determine its suitability for specific uses.
Many traditional sources of graphite supplied the lower grade requirements of the industrial market - primarily for refractory purposes such as crucibles, electrodes, and insulators. Demand for this category of graphite is expected to remain relatively constant.
However, most new applications for graphite require specific qualities that can not be met by many known sources. Expandable graphite (used for heat and fire protection in applications ranging from building materials to consumer electronics and fuel cells), thermal sheets, gaskets and seals require very large flakes.
Perhaps the most exciting developments in the graphite market are occurring in the multiple applications for graphene – ranging from concrete reinforcement to lighter airplane wings to medical sensors to water filtration. According to Grand View Research, the global graphene market is expected to expand at a CAGR of 38.7% from 2020 to 2027. However, the properties of graphene depend strongly on its structure and hence for high-tech application - high-purity graphene requires high-purity graphite for its production.
The largest growing segment for graphite (battery anode material) has a very low tolerance for impurities - especially very specific impurities. Reflecting the importance of the qualities of the graphite on the performance of an EV vehicle (battery storage capacity, battery cycle life, capacity retention over cycles) the qualification process can take up to 24 months.
Graphite occupies up to 30% of an EV battery cell, but only 7% of the price. Accordingly, EV manufacturers will place a premium on highest purity flake graphite.