Even though battery separators are not an active part of the Li-ion battery assembly, the microstructure of the separator affects ion transport and has a considerable impact on the overall performance and lifetime of the battery. Understanding the influence of the separator microstructure on the battery performance opens a vast potential for improvement of battery design.

This tutorial illustrates the capabilities of the GeoDict software to digitally analyze and optimize the microstructure of battery separators. Following the tutorial, you learn to import and crop the pre-processed microstructure of a segmented FIB-SEM scan of a Celgard PP1615 Lithium-Ion Battery Separator in GeoDict. Then, you calculate the geometric (morphological) and transport properties of the microstructure and identifies a representative elementary volume (REV). On this REV, the electrolyte-separator interaction is computed, and mechanical deformation is simulated. The geometric and transport properties are then discussed for the mechanically deformed structures as well.