Modeling coupled electrochemical and mechanical behavior of soft ionic materials and ionotronic devices

Abstract

Recently there has been an increase in demand for soft and biocompatible electronic devices capable of withstanding large stretch. Ionically conductive polymers present a promising class of soft materials for these emerging applications due to their ability to realize charge transport across the polymer network, while preserving the desired mechanical and chemical features. As opposed to electron transfer in traditional electrical conductors, the charge transport across these polymers is achieved through ion migration. When such materials are used in combination with electrical systems, they are known as ionotronic devices. The ability to simulate device performance based on its material composition and geometry would accelerate and improve ionotronic device design. The main challenge in developing reliable simulation capabilities for ionically conductive polymers is the complex and coupled electro-chemo-mechanical behavior. In this work we address this challenge by introducing a multiphysics framework incorporating the coupled effects of ion transport, electric fields and large deformation. The utility of the developed multiphysics model is showcased by simulating representative ion transport problems and the operation of soft ionotronic devices.