You are using an outdated browser. Please upgrade your browser to improve your experience.
Javascript is disabled in your web browser. For full functionality of this site it is necessary to enable JavaScript.
This website is using cookies.
We use them to give you the best experience. If you continue using our website, we'll assume that you are happy to receive all cookies on this website.
CPOTE2020 logo
6th International Conference on
Contemporary Problems of Thermal Engineering
Online | 21-24 September 2020

Abstract CPOTE2020-1292-A

Book of abstracts draft
slider slider slider slider slider slider

Tailoring SOFC electrodes' microstructure using 3D representative volume element generation and evolutionary computing

Szymon BUCHANIEC, AGH University of Science and Technology, Poland
Marcin MOŹDZIERZ, AGH University of Science and Technology, Poland
Tomasz PROKOP, AGH University of Science and Technology, Poland
Grzegorz BRUS, AGH University of Science and Technology, Poland

Solid oxide fuel cell has a high energy conversion efficiency and emits a low level of pollutants. Two of the crucial elements are electrodes that are typically a composite of ion and electron-conducting materials with a complex microstructure to promote the electrochemical reactions. The microstructure morphology of an electrode plays an important role in determining the electrochemical performances of a single cell and, consequently, a stack of cells. Therefore, the microstructure optimization design should be a part of developing a system at a very early stage. The electrode material microstructure can be locally-resolved to fulfill the role it has at a particular location in the stack. This study focuses on the optimization of the morphological features of solid oxide fuel cell electrodes for the given working conditions. For the optimization method, an evolutionary algorithm is adopted. The chosen optimization method allows screening of hundreds of candidate solutions represented by the vector of microstructural parameters. The functional dependencies among the microstructural parameters are obtained using representative volume element generation techniques to ensure a feasible solution. Each set of microstructure parameters is evaluated by an extremely fast reduced model of SOFC. The properties of the best electrodes are combined to create a new generation of solutions. The algorithm is iteratively repeated until converging criteria are met, and an optimal microstructure is found. The feasibility of the obtained optimal solution was validated by reconstructing the three-dimensional digital model of the optimal microstructure with parameters proposed by the algorithm. It was shown that the presented approach supports the design of electrodes and thereby can lead to the improvement of the solid oxide fuel cell stack's performance. Optimal structures promote gas and ion transport phenomena by increasing the volume fraction of pores and ionic conductors. Because of the high mobility of electrons, the electron-conducting phase fraction is at the minimum necessary to maintain connectivity and high reaction domain. The obtained values of microstructural parameters and relations between them are in good agreement with the literature. The obtained results unveil the direction to optimize complex 3D structures, which would further improve the microstructure design in the future.

Keywords: Solid oxide fuel cell (SOFC), Mathematical modelling, Microstructure, Optimisation, Microscale simulation
Acknowledgment: The „Easy-to-Assemble Stack Type (EAST): development of new solid oxide fuel cell stack for the innovation in Polish energy sector” project is carried out within the FIRST TEAM programme of the Foundation for Polish Science co-financed by the European Union under the European Regional Development Fund.