Work

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

Year: 2021

Type: article

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

Source: Macromolecules

DOI: 10.1021/acs.macromol.0c02545

Authors: Kara D. Fong, Julian Self, Bryan D. McCloskey, Kristin A. Persson

Institutions: Lawrence Berkeley National Laboratory, University of California, Berkeley, Molecular Foundry

Language: English

Topic: Advanced Battery Materials and Technologies

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $5,000

Funders: National Science Foundation, Vehicle Technologies Program