Addressing Strain and Porosity Changes of Battery Electrodes Due to Reversible Expansion through DEM Simulations

Abstract

In this work, discrete element method (DEM) simulations were used to probe changes in electrode porosity, electrode strain, and the resultant pressure changes for composite electrodes comprised of active material and binder particles. Through the results acquired by these simulations, three cases that are representative of two limiting cases for electrode operation, and one case for realistic electrode face pressure during operation were captured and the implications on design and performance are discussed. Predicting changes in the porosity is a unique insight that is difficult if not impossible to capture experimentally but is important for predicting changes in electrochemical performance during cycling, and should be addressed early on in the design phase for automotive and grid storage battery design and performance.