(Invited) Ionic Transport and Structure of Battery Electrolytes, Electrodes and Interfaces: New NMR, Diffraction and Optical Microscopy Approaches

Abstract

This talk will discuss the development and use of new characterisation methods to understand function over different time and lengthscales, to improve materials function and battery performance. We show how electrode material function can be studied with NMR to measure transport, X-ray diffraction to measure phase segregation within the bulk, optical measurements to explore processes at the particle level, and continuum modelling to tie transport with particle level observations. In the examples discussed, NMR measurements provide hopping frequencies and diffusion coefficients and operando diffraction measurements provide evidence for solid solution vs two phase behaviour as a function of cycling. New optical measurements then allow phase transformation and phase fronts to be visualized directly. The processes that underpin the formation and movement of various phase fronts can then be explored via simulations. Applications to both anode cathode materials will be described. Finally new approaches to investigate the structures of pristine and degraded electrolyte will be discussed.