Lithium-ion batteries go cobalt-free

Abstract

Lithium-ion battery cathodes have always relied on cobalt, but the expensive metal's supply chain is fraught with issues. A new cobalt-free cathode could provide reprieve ( 2020, DOI: ). In lab tests, lithium-ion battery cells made with the new cathode held more energy over hundreds of charge cycles than commercial ones. Battery cathode materials are layered crystals of lithium metal oxides. Cobalt is key for boosting energy density and battery life because it keeps the layered structure stable as lithium ions get reversibly stuffed into and extracted from the cathode during battery operation. But some carmakers want to eliminate cobalt entirely, given its scarcity and the ethical considerations around mining the metal. About two-thirds of the world's cobalt mining is done in the Democratic Republic of Congo, where operations are linked to human rights and environmental abuses. But cobalt-free cathodes have lagged in performance and haven't been tested in practical