Julia Yang, PhD, Environmental Fellow at Harvard University

Decarbonization goals for Net Zero Emissions by 2050 will be accomplished through widespread electrification of transportation fleets. Electric vehicles with high energy densities and acceptable cycle life are partly making this possible. However, as restrictions on critical materials in these devices tighten, the success of earth-abundant battery chemistries and scalable battery recycling become increasingly urgent.

In this talk, I explain how relaxing structural constraints for conventional battery electrodes, presumed to lead to sluggish Li diffusion, in fact results in partially disordered materials with ultrahigh power and energy density. Comprised of only earth-abundant Mn, these electrodes deliver specific energy greater than 900 Wh kg-1 within minutes. I explain how discharge occurs via a solid solution reaction and that excellent rate capability arises from Li transport throughout a newly activated inter-network and a largely intact intra-network. Our findings indicate incorporating partial spinel order is essential for accommodating ultrahigh rate performance in next-generation, earth-abundant electrodes.

To attain a sustainable energy transition, methods to recover metals from end-of-life batteries will need to be carefully developed. I conclude with a working critique on green solvents that have been recently demonstrated to leach cobalt and other transition metals with high efficiency.