In my column, Barry on Batteries, I discuss the role of graphite in lithium ion batteries. While lithium, nickel, and cobalt often dominate the conversation, graphite quietly plays a pivotal role—both in performance and sustainability.
Graphite is the heaviest and largest component by volume in a lithium-ion battery, comprising up to 28% of its weight. A single battery contains approximately 10 to 15 times more graphite than lithium—yet it’s frequently overlooked in supply chain discussions.
Sources and Processing: Natural vs. Synthetic Graphite
Natural graphite is mined in medium and fine flakes or in amorphous form from coal seams and a rare vein graphite from Sri Lanka. It makes up nearly 95% of battery-grade graphite supply, predominantly sourced from China; the remaining 5% comes from Japan, the U.S., Madagascar, and Mozambique,
Synthetic graphite, made from petroleum or needle coke in energy-intensive high-temperature furnaces, provides alternatives but comes with hefty environmental costs. Advances in energy-efficient furnaces and renewable energy options—like wood biomass—show promise for mitigating these impacts.
Graphite must be ultra-pure (99.95%+) and precisely shaped for use in batteries. This includes grinding and rounding to form spherical graphite (SPG), ideal for anodes due to its smoothness and small particle size, which helps reduce capacity loss and extend battery life. The SPG is then blended with binders and wetting agents to create an anode slurry, which is coated onto copper foil as part of the battery assembly process.
Recycling: A Circular Opportunity
Recycled graphite is rapidly emerging as a game-changer. Research has shown that recycled graphite matches natural and synthetic graphite in physical and electrical performance including particle size, purity, surface area, tap density, capacity retention, and overall performance.
Recovery begins with shredding and granulating end-of-life batteries into “black mass” where graphite can compose around 40%. Mechanical pretreatment, vacuum drying, and sorting separate the binders and coatings that complicate graphite recovery. Recycling facilities then employ specialized methods—like sieving, flotation, green solvents, or heat—to isolate and reclaim graphite for reuse.
Graphite & Sustainability
Graphite is far more than a passive component as it impacts battery weight, volume, and cost. However, supply is concentrated, processing is energy-heavy, and recovery is intricate.
Sustainable practices such as advanced manufacturing, synthetic alternatives, and recycling efforts can reposition graphite in a circular battery economy.
For more information, please visit my lithium page.