NMR study of electrolytes for Li rechargeable batteries: from liquid to solid electrolytes

A fundamental understanding of lithium-ion (Li + ) interactions and ion-transport mechanisms in electrolytes is essential for the development of high-performance energy-storage systems. Nuclear magnetic resonance (NMR) spectroscopy serves as a powerful tool for elucidating Li + coordination environments, ion dynamics, transport pathways, and the formation and evolution of solid–electrolyte interphases (SEIs) at electrode–electrolyte interfaces. This review summarizes recent NMR-based studies on liquid, inorganic solid, and polymer electrolytes, highlighting how chemical-shift analysis, multidimensional correlation experiments, relaxation measurements, pulsed-field gradient (PFG) techniques, and isotope-exchange NMR reveal the relationships between local structure and the short- and long-range dynamics of Li + ions. Collectively, these advances underscore the importance of NMR spectroscopy in guiding the rational design of high-performance electrolyte systems for lithium rechargeable batteries.