Latest and Greatest in GeoDict 2027 for Electrochemistry Applications

This presentation provides an overview of recent developments in GeoDict for modeling electrochemical energy storage and conversion systems, with applications to batteries, fuel cells, and electrolyzers. 

New capabilities for generating realistic 3D microstructures expand the range of systems that can be modeled. An AI-based approach reconstructs 3D microstructures from 2D images for materials such as conventional Li-Ion NMC cathodes, ASSB-cathodes, or PEM fuel cell catalyst layers (CL). In addition three new GeoApps provide dedicated microstructure generation for solid oxide fuel cell electrodes, solid-state battery cathodes, and PEM fuel cell catalyst layers. The generated microstructures can be customized and used directly for image analysis, virtual testings, and multiphysics simulations.

For battery simulations, improved parametrization in BatteryDict simplifies the definition of open-circuit voltage, diffusivity, and conductivity as functions of stoichiometric (absolute) lithium concentration. This facilitates the use of experimentally measured and literature-based material properties. Mechanical degradation caused by volume changes during lithiation and delithiation can also be simulated, including failure within active materials that expand during lithiation.

Further developments extend the range of processes that can be investigated directly on resolved microstructures. Time-resolved saturation simulations provide insight into electrolyte wetting of battery electrodes as well as liquid saturation of gas diffusion layers (GDL) or CLs of PEM fuel cells. Electrochemical Impedance Spectroscopy (EIS) can now be simulated using the same microstructure-based model employed for electrochemical simulations without requiring an equivalent-circuit representation. This provides a direct link between microstructure, material parameters, and experimentally measured impedance data. 

The material database has also been extended with materials for sodium-ion batteries, supporting the simulation and investigation of this emerging battery technology.

Finally, new transient heat transport capabilities heat conduction and heat transfer associated with fluid flow through the microstructure. This is particularly relevant for PEM fuel cells and electrolyzers, where the local temperature distributions, including those near the membrane, are influenced by the transport of gases and liquids through the system.

Together, these developments provide a more integrated framework for generating electrochemical microstructures and investigating their couples electrochemical, mechanical, fluid, and thermal behavior.