The Problem With Graphite
Hardly a day goes by without another news article highlighting some critical mineral supply or geopolitical risk. Minerals such as lithium, nickel, copper, magnesium, graphite, and rare earths are key to the energy transition given the massive ramp up of battery manufacturing and electrification, or are inputs to aerospace and defense applications.
Let’s deep dive into one of these minerals in particular: graphite. A crystalline form of pure carbon, graphite’s unique combination of high conductivity, thermal resistance, and other characteristics make it essential across a variety of industries including steelmaking, nuclear reactors, refractory materials, brakes, lubricants, and batteries.
Although batteries currently comprise ~20% of graphite demand, the industry is anticipated to drive the majority of forecast demand, to the point where the world faces a >3x deficit of graphite supply by 2030.
This daunting challenge is exacerbated by the fact that China produces ~70% of the world’s natural graphite and ~50% of synthetic graphite, and controls nearly 100% of the refining process. Coated spherical graphite, the key ingredient in lithium ion battery anodes, may be cheaper and less sexy than lithium, but it comprises 20–50% of a battery by weight.
A dirty process for a clean future
Unfortunately, producing graphite has historically been a polluting endeavor. There are two types of graphite: natural graphite which is mined, and synthetic graphite derived from petroleum coke.
Natural graphite is extracted as ore, then goes through the beneficiation steps of crushing, grinding, screening, and flotation to remove impurities. This process suffers from the same environmental concerns that plague all mines.
Synthetic graphite, on the other hand, starts with petroleum coke (a byproduct of oil refining), before undergoing calcination at ~1400°C and graphitization at ~3000°C. Achieving such high temperatures requires immense amounts of energy, to the point where synthetic graphite from China generates 2–4x more emissions than natural graphite.
Various efforts to build domestic sources of graphite are underway, but those companies expect customers to pay premiums of between 30–50% compared with Chinese graphite.
As a result, labs and startups are attempting new methods to synthesize graphite, using other carbon feedstocks like methane, biomass, and coal. We’ll explore some of these methods in the next post.
