Tracing global cobalt flow: 1995-2015

Cobalt is an essential metal for next-generation clean technologies. In this study, a long-term trade-linked material flow analysis model is established to analyze cobalt flows throughout the metal's anthropogenic life cycle and across national boundaries during the 1995-2015 period. The results indicate that driven by more cobalt applications discovered and developed, global cobalt supply and demand have experienced rapid growth in recent decades. Global cobalt in-use stock reached 220 kilotons in 2015, which is mainly embodied in laptop computers. The major opportunity for secondary cobalt recovery exists in the cobalt stock contained in battery applications. Cutting the excess productivity of batteries is essential to improving cobalt utilization efficiency. A globally-distributed cobalt trade network has been established. Democratic Republic of the Congo, the United States, China, and Japan are the major powers in the trade network. Countries with strong dependence on cobalt imports face a high risk of cobalt shortages. The establishment of domestic cobalt reserves and the development of cobalt substitutes are viable options for these countries. Besides, international coordination and governance through the whole value chain of cobalt should be under consideration. High attention need to be paid on harmonizing the extraction of cobalt and other companion metals, mostly copper and nickel.