Harnessing interfacial solvation structure for next-generation secondary batteries

Interphase chemistry between electrodes and electrolytes plays a key role in the performance of secondary batteries. Recent studies have revealed that interphase chemistry is closely correlated to the evolution of the interfacial solvation structure (ISS). However, complex ion–solvent interactions in the interfacial region in practical batteries make it challenging to understand the dynamics of the ISS using classical electric double layer models. Here we examine the thermodynamic and kinetic properties of the ISS, including the interfacial coordination structure, ion migration and desolvation behaviour. By regulating these properties, the construction of anion- and additive-rich ISSs can facilitate the formation of highly conductive and robust solid–electrolyte interphases in moderately concentrated electrolytes, improving the Coulombic efficiency, stability windows and desolvation kinetics, even under extreme operating conditions. We highlight how interdisciplinary strategies that combine advanced characterization techniques with computational simulations powerfully resolve the dynamic evolution of the ISS at an atomistic level. Lessons from electrocatalysis, where electrolyte effects and interfacial structuring have been successfully deciphered, further illustrate how such approaches can inspire progress in understanding and harnessing the ISS for next-generation batteries.