Graphite is a crystalline form of carbon used as the anode material in virtually all commercial lithium-ion batteries, as well as in steelmaking, refractories, lubricants, and nuclear moderators. Refining transforms mined flake graphite or synthetic graphite into the high-purity forms industry requires, most notably spherical purified graphite (SPG) for battery anodes, which typically must reach 99.95% carbon purity or higher.
Two main refining routes exist. The hydrofluoric acid (HF) route, dominant in China, is cheap and effective but generates hazardous fluoride waste. The thermal purification route, used by some Western and Japanese producers, heats graphite above 2,500°C to vaporize impurities; it is cleaner but energy-intensive and costly. Refining also includes micronization, spheroidization (rounding flakes into potato-shaped particles), and surface coating with pitch or carbon.
Politically, graphite refining is a focal point of critical minerals policy because the supply chain is highly concentrated. According to the US Geological Survey and IEA assessments, China accounts for roughly two-thirds of mined natural graphite and the large majority of global anode-grade refining capacity, including nearly all spherical graphite processing. This concentration prompted several policy responses:
- The US Inflation Reduction Act (2022) made battery materials sourced or processed in China ineligible for full EV tax credits via its Foreign Entity of Concern rules, with graphite given a temporary exemption that has been progressively tightened.
- The EU's Critical Raw Materials Act (2024) lists natural graphite as both critical and strategic.
- In October 2023, China announced export controls on certain graphite products, requiring permits for high-purity and spherical graphite shipments, citing national security.
Junior researchers should distinguish mining (Mozambique, Madagascar, China, Brazil dominate) from refining (overwhelmingly China), as the chokepoint sits at the refining stage rather than at the mine.
Example
In October 2023, China imposed export permit requirements on high-purity graphite and spherical graphite, tightening its grip on a refining stage where it holds an estimated 90%-plus global share.
Frequently asked questions
Mining is geographically diverse (Mozambique, Madagascar, Brazil, China), but the conversion to battery-grade spherical purified graphite is concentrated in China, which controls an estimated 90% or more of global anode-grade refining capacity.
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