Keynote
NMR, MRI AND PDF STUDIES OF NA, Li-METAL AND LI-AIR BATTERIES

This talk will describe the use of NMR and MRI spectroscopy to characterize a series of “beyond-Li” electrode materials. The NMR results are combined with complementary techniques such as pair distribution function analysis of (X-ray) scattering data. In the sodium-ion battery case, ²³Na NMR spectroscopy can be used to follow changes in local structure in a manner very similar to that performed on lithium-ion battery materials. Our work using the method to study local structure and Na⁺ and electronic ordering in positive layered materials and intermetallic anodes will be described. The use of NMR and MRI (magnetic resonance imaging) to link structural changes with electrolyte concentrations will be demonstrated for lithium metal anodes. Finally, new developments in the field of lithium-oxygen batteries will be described. In particular NMR spectroscopy allows the different discharge products and many side-reactions to be followed. For example, ¹H and ⁷Li NMR spectroscopy can be used to separate Li₂O₂ from LiOH, allowing batteries that cycle via LiOH to be characterized. Our recent studies with LiI redox mediators and r-GO electrodes will be described.