Mechanistic Insights into Rechargeability and Capacity Limitations in Nonaqueous Li-O2 Batteries

Multiple directions in battery research are now being pursued in hopes of advancing beyond the specific energy limits imposed by conventional Li-ion electrode materials.  For example, ‘beyond Li-ion’ battery chemistries, such as Li-O₂, Li-S, and Mg-ion, are currently being explored as potential successors to Li-ion batteries given their very high theoretical specific energies; yet severe technical challenges have prohibited them from becoming a practical reality.  The objective of this presentation is to provide an assessment of such challenges, in particular, instabilities of the electrolyte and cathode, and Li₂O₂ electronic conductivity limitations, facing the nonaqueous Li-O₂ battery cathode. Results will be presented on the characterization of the Li₂O₂ formation mechanism and how the mechanism could be engineered to potentially alleviate problems associated with Li₂O₂ deposition on the cathode.