Nuclear magnetic resonance studies of organic-inorganic composite solid electrolytes

Solid electrolytes have received widespread attention due to their higher safety than liquid electrolytes in the past decades. In particular, organic-inorganic composite solid electrolytes (CSEs) in which inorganic fillers dispersed in polymer solid electrolytes are considered to be one of the most promising candidate electrolytes for high-performance solid-state lithium batteries. Understanding the local environments and the conduction pathway/dynamics of Li⁺ is essential for the design of high-performance CSEs. Nuclear magnetic resonance (NMR) is a non-invasive quantitative technique that has unique capabilities in providing molecular structure information, morphological evolution, and measuring the movement of ions at different time scales. Therefore, for battery researchers, an accurate and comprehensive understanding of the basic principles and experimental design of solid-state NMR (SSNMR) is of great significance for investigating the abundant molecular structure and dynamics information in CSEs. The specific applications of the SSNMR technique in CSEs are briefly introduced in this present review.