Performance Modeling of Hydrogen-Production Electrolysis Cells for Scaling up Electrochemical Materials
Authors: Ma Zhiwen , Witteman Liam , Boyer Hailey , Gifford Jeffrey 
Published: May 2020

This presentation will introduce modeling methods of an electrochemical cell and correspondent computational tools that enable the implementation of materials into a component design for assessing their performance, lifetime and reliability through high-fidelity modeling methods. The component modeling tools use ANSYS software as a solution framework, by adding fundamental thermochemical, electrochemical, and thermomechanical models, for simulations from basic material properties to a full-product design. The thermochemical and electrochemical modeling tools were developed from the fundamental transport and chemical processes from basic material performance data and correlations to reduce prediction uncertainties. By incorporating the specific mathematical descriptions for hydrogen-production processes, the modeling methods can be adapted to various electrolysis cell types as a general approach for electrolysis device design or performance optimization, because a common solver platform is used and expands the functionality of the computational fluid dynamics (CFD) software, ANSYS/Fluent with an add-on electrochemical module through Fluent’s User Defined Function (UDF). Particularly, we have developed models for high-temperature electrolysis (HTE) using proton-conducting solid oxide electrolysis cell (H-SOEC), low-temperature electrolysis (LTE) of proton-exchange-membrane electrolysis cell (PEMEC), and carbon-dioxide reduction (CO2R) cells.

These multi-scale electrochemical modeling tools have been used for component performance simulations and are for studying material implementation at the cell and stack level. Appropriate mathematical descriptions of the electrochemical and thermochemical processes were developed for a given system based on the underlying material performance taken from either experimental data or theoretical modeling results. The modeling practices were previously successfully applied to fuel cell design and transformed for electrolysis cell design. The integral modeling tool provides insights into new materials or components that can be or are being implemented into electrochemical cell and stacks. Furthermore, the computational tools can support the electrolyzer design, performance, degradation and life cycle predictions, and may accelerate the material implementation into a product with proper design and optimum performance conditions.

The presentation will show that the computational modeling links experimental materials research with a component or product using high-fidelity thermochemical and electrochemical models. The focus of this presentation will be on the modeling method and results for the H-SOEC electrolysis cells. The approach will facilitate material R&D in general and improve the computational tools to support industry for predicting product and life cycle performance. Validation of component performance and system integration results against prototype designs can allow iterative improvements to the model and to various types, processes, and scales of systems.