Ion Correlations and Their Impact on Transport in Polymer-Based Electrolytes

The development of next-generation polymer-based electrolytes for energy storage applications would greatly benefit from a deeper understanding transport phenomena in these systems. In this Perspective, we argue that the Onsager equations provide an intuitive but underutilized framework analyzing electrolytes. Unlike ubiquitous Stefan–Maxwell equations, generates coefficients with clear physical interpretation at atomistic level and can be computed easily molecular simulations using Green–Kubo relations. Herein present overview theory as it applies to discuss its relation experimentally measurable properties equations. Using case studies recent computational work, demonstrate how clarify nonintuitive such negative cation transference number, anticorrelated cation–anion motion, dramatic failure Nernst–Einstein approximation. We insights analysis inform design rules improved