Research Rotation Project

Characterization of Ionic Liquids and Amorphous Materials for Mg Battery Applications

Jeff Yarger
Home Department - Chemistry and Biochemistry
Areas of Study - Biopolymers, Polyamorphic Materials, High Pressure Materials, Quantum Dots, Fuel Cell and Battery Materials
Office - ISTB1 470
Phone - 6235659913
E-mail - jyarger@gmail.com
Designation - Experimental

Breakthrough developments in cathode, anode and electrolyte materials will be required to realize the potential advantages of Mg in secondary battery technologies. All three will be explored as part of this focus area. These include developing a comprehensive understanding of Mg/Mg2+ redox processes in media that are stable toward this highly active metal (especially including ionic liquids), developing new Mg2+ insertion cathodes, and investigating new electrolyte systems for facile Mg2+ transport. The tools that will be employed include synthesis, electrochemical characterization, and state-of-the-art structural analysis using NMR, neutron and X-ray techniques. One objective is to understand at a fundamental level why the cycling rates are so low for Mg2+ insertion and deinsertion in most materials. One approach to solve this issue is to use nanoscale materials to reduce the diffusion distance for Mg2+ in the solid. More specifically, we will explore new organic-inorganic nanoscale hybrid materials that enable rapid Mg2+ transport while simultaneously facilitating electron percolation through the cathode structure. For example, Figure 1 shows the unusually facile multiple cycling we observe for Mg2+ insertion/deinsertion into redox active MnO2 nanoparticles embedded in a layer-by-layer (LbL) nanostructure. We also will employ these materials to create new 3D battery architectures using the control of hierarchical nanoscale structure approaches discussed above. From the standpoint of anode systems, our objective is to develop solvent systems with facile Mg/Mg2+ redox cycling. This part of the effort will be guided considerably by the results of characterization of the state of Mg2+ in ionic liquids, as well as theoretical studies of the Mg/ionic liquid interface. The overall goal of the project is to develop a new paradigm for electrochemical energy storage based on the Mg/Mg2+ multi-electron redox couple.