Quantitative Phase Field Model for Electrochemical Systems

Abstract

Modeling microstructure evolution in electrochemical systems is vital for understanding the mechanism of various electrochemical processes. In this work, we propose a general phase field framework that is fully variational and thus guarantees that the energy decreases upon evolution in an isothermal system. The bulk and interface free energies are decoupled using a grand potential formulation to enhance numerical efficiency. The variational definition of the overpotential is used, and the reaction kinetics is incorporated into the evolution equation for the phase field to correctly capture capillary effects and eliminate additional model parameter calibrations. A higher-order kinetic correction is derived to accurately reproduce general reaction models such as the Butler-Volmer, Marcus, and Marcus-Hush-Chidsey models. Electrostatic potentials in the electrode and the electrolyte are considered separately as independent variables, providing additional freedom to capture the interfacial potential jump. To handle realistic materials and processing parameters for practical applications, a driving force extension method is used to enhance the grid size by three orders of magnitude. Finally, we comprehensively verify our phase field model using classical electrochemical theory.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 01, 2023
Source ID
10.1149/1945-7111/ad0ff6

Entities

People

  • Alexander F Chadwick
  • Jin Zhang
  • Peter W. Voorhees

Organizations

  • Office of Naval Research

Tags

Readers

  • Computational Fluid Dynamics (CFD)
  • Computational Modeling and Simulation
  • Electrochemical Engineering/ Fuel Cell Technologies