Liquid-State NMR Spectroscopy for Battery Electrolyte Design

Electrolytes transport ions and maintain interfacial stability, thus playing a pivotal role in determining battery performance. Liquid-state nuclear magnetic resonance (ls-NMR) spectroscopy has emerged as a powerful tool to elucidate the underlying electrolyte chemistry. However, the testing protocols and analysis criteria have not been fully standardized. In addition, the correlations between spectroscopic results and electrolyte chemistry are complex and poorly characterized. Therefore, it is imperative to clarify the principles of ls-NMR spectroscopy and the roles it can play in improving our mechanistic understanding of liquid battery electrolytes. In this Perspective, several emerging ls-NMR techniques are categorized and discussed, with an emphasis on visualizing the solvation effect, ion dynamics, and intermolecular interactions in liquid electrolytes. We demonstrate how ls-NMR spectroscopy can be used to understand electrolyte chemistry and expedite electrolyte design for emerging battery technologies.