Natural graphite is used in a myriad of modern industries from the steel industry to the lithium ion batteries industry and for the automotive industry in the form of brake linings, gaskets and clutch materials. It is important for refractories as well as the simple pencil alike, which just shows how important graphite is in our everyday lives though it is hardly seen or talked about. Graphite is a crystalline form of the element carbon.
Graphite is a distinct material that displays the properties of both metals and non-metals. Derived from the Greek word ‘graphien’ which means ‘to write’ graphite has an opaque greyish black colour and is composed of stacked sheets of carbon atoms with a hexagonal crystal structure. It is owing to this crystalline structure that graphite enjoys the uncommon properties of being flexible though not elastic along with high electrical and high thermal conductivity. It is lighter than diamond and smooth and slippery to the touch. Graphite can be found mainly in metamorphic rocks formed by the deterioration of organic compounds during metamorphism. It is also known by the names plumbago and black lead.
Natural graphite can be found in three different main forms all of varying degrees of purity and structure and are used for different purposes.
Synthetic graphite is a material manufactured by a complex process of baking petroleum coke at a very high temperature. While it has a high purity level of over 99% carbon it is a costly manufacturing procedure as it is power intensive and environmentally unfriendly.
Graphite demand is ever increasing as it continues to play a leading role in the energy transition narrative. It is the largest component in the lithium-ion battery market while also being important for the manufacturing of gaskets and brake linings. As the world continues to embrace a green drive towards natural and renewable energy graphite’s industrial applications will continue to grow as there are no known substitutes currently.
Historically, the graphite market has been driven by industrial demand and growing EV and battery demand have proved to be key growth drivers for the graphite market. It is a popular material in numerous industries owing to its newfound applications and for not having adverse effects on the environment.
According to Benchmark the supply and demand imbalance during 2022 caused prices for mesh flake graphite to rise by 25% which is predicted to continue. Rising prices on strong anode demand are expected to incentivise new supply in 2023, with four new mines anticipated to join the flake graphite market with supply set to grow by around 15%. Generally, the graphite market is projected to expand at CAGR of 8.01% over the forecast period of 2023-2028.
The three main types of natural graphite have their specific characteristics and roles in various modern industries.
Flake graphite – Natural flake graphite has a very high purity range of about 80-98% carbon and gets its name from the fact that it typically forms in flakes or plates and can start its geological life as either an organic or inorganic carbon. It has a distinctly flaky morphology. Depending on conditions under which they are created the size, shape and purity of the flakes will vary. It is one of the most buoyant minerals in nature thanks to its good surface properties and flake structure. China is one of the leading producers of flake graphite.
Vein graphite – Crystalline vein graphite offers high thermal and electrical conductivity, resistance to oxidation and high temperatures, chemically inert, lubricating properties, high density and is environmentally friendly. It is formed from direct deposition of solid graphitic carbon from high temperature subterranean fluids known as pegmatitic fluids. Vein graphite is above 90% pure with some even reaching 99.5%. Sri Lanka has some of the purest vein graphite available on the planet and is one of the main producers of vein graphite for the global market.
Amorphous graphite – Despite the name this is a crystalline as are all graphite varieties. This is a very fine-grained and generally sooty graphite formed by the metamorphism of previously existing anthracite coal seams. It is found as minute particles in beds of mesomorphic rocks such as coal or slate. Generally amorphous graphite is available at a purity of about 75-85% carbon and tends to be much less reflective. China and Mexico are the largest producers of amorphous graphite.
Graphite is also a main staple in the technology manufacturing sector, nuclear engineering, semiconductors while being essential to electrification for the anode part of the battery with no substitutes currently available. Natural graphite is fast proving to be an indispensable material for many modern industries with predictions that to meet the 2035 graphite demand, the graphite industry will need close to 97 new mines.
Based on their purity and type these graphite varieties are used across different contemporary industries.
Flake graphite – graphite flakes are used in the automotive industry for electric motors, refractory and nuclear power, as a general lubricant, friction moderator, fuel cells, as thermal material, powder metallurgy, coatings and in pencils.
Vein graphite – used in brake linings, lubricants, refractory materials, battery cells, carbon brushes, brake linings, lithium-ion batteries and the plastic industry to name a few. Vein graphite, thanks to its high performance, is mostly used in thermal and high friction application industries such as those making car brakes and clutches.
Amorphous graphite – this type of graphite is used in a variety of industries such as the casting and strengthening of steel, crucibles, nozzles and troughs that can withstand very high temperatures. It is used in electrodes including electric arc furnaces used in steel processing. It is also used in blast furnace linings and brake linings.
The lithium-ion battery industry, refractories and the steel industry have historically been the main driver of consumption with sustained robust growth which will ensure continued demand. Currently there are no substitutes for the anode part of a battery which makes graphite essential for electrification. As a growing number of countries around the globe strengthen their efforts to encourage production and use of green energy so as to transition towards lower-emissions in the energy and transport sectors, the role of commercial graphite as a key component will continue to grow.