Thermo-chemo-mechanical stress analysis in a thin-electrolyte plate of all-solid-state battery

Abstract

Stress fields of the electrolytes of all-solid-state batteries can be induced by several factors, such as temperature variations, lithium-ion distributions, and mechanical constraints. In this study, the thermo-chemo-mechanical stress field in an electrolyte was formulated using plate theory, assuming an infinite thin-electrolyte plate in a planar battery system. The stress fields were successfully calculated with consideration of property variations with temperature and lithium concentration under various conditions of temperature gradients, lithium concentration profiles, and mechanical boundary constraints. The extent to which the property variations affected the stress fields was also demonstrated. From these calculated stress distributions, an estimation method of the critical conditions for safe operation was proposed to limit maximum stress induced in electrolytes.