(670a) Novel Cathode Materials for Rechargeable Aluminum Batteries

Aluminum metal is one of the most coveted electrode materials for rechargeable batteries because it is inexpensive, globally abundant, non-flammable, non-toxic, and has a volumetric energy capacity almost four times greater than lithium metal. However, its widespread use in rechargeable batteries has thus far remained elusive, in part due to the limited number of cathode and electrolyte materials that can reversibly electrochemically cycle with aluminum metal anodes. Here, novel cathode materials for rechargeable aluminum batteries will be presented that are based on graphene and sulfur-containing materials (e.g., transition metal sulfides). Characterization of the cathode materials will be discussed as a function of state-of-charge and cycle number, emphasizing molecular-scale understanding of the reaction mechanisms via multi-dimensional NMR spectroscopy, X-ray diffraction, electron microscopy, and electrochemical methods. The results yield insights into design strategies for synthesizing next-generation cathode materials with improved energy densities, rate capabilities, and cycle lifetimes.