Lithium-ion battery material circularity: material availability, recycling economics, and the waste hierarchy

Electric vehicles (EVs) are a critical element of strategies for decreasing global greenhouse gas emissions. EVs are powered by lithium-ion batteries, which are material-intensive and require mining and processing that result in environmental and social impacts. Several governments, including the European Union, the state of California, and the Republic of China, have recognized that reusing, repurposing, and then recycling the battery at its end-of-life, also known as the waste hierarchy, is necessary to mitigate the externalities of the transition to EVs. Policy focused on the lithium-ion battery end-of-life have focused on recycling, and particularly on recovering cathode materials instead of the anodes and other materials, due to their comparably higher environmental, economic, and social impacts, as well as the geographical concentration of production. Prior studies have evaluated these impacts but have not considered the influence cathode chemistry and technological development may have on material circularity, resulting in a difference of material composition between batteries reaching their end-of-life and batteries currently being manufactured.For policies intended to create a circular EV battery industry to be effective, the quantity of materials reaching their end-of-life, and the environmental and social tradeoffs between end-of-life solutions, must be determined. This research uses methods from industrial ecology, including material flow analysis and life cycle analysis, to address a gap in lithium-ion battery policy; in particular, the design and evaluation of policies that consider the rapid evolution of lithium-ion battery technologies which will result in decreased use of cobalt and an increase in energy density. Material flow analysis is used to calculate spatially and temporally resolved battery material flows and propose a method for calculating feasible recycled content standards, accounting for cathode chemistry mix, EV sales, and lifespan. Technoeconomic assessment is used to evaluate the cost of recycling, considering location, cathode chemistry, and transportation mode. Lastly, life cycle analysis is used to evaluate the material life cycle impacts of directly recycling high cobalt batteries in comparison to extending the lifespan through reuse