Research project

Multiphysics Modeling of Delamination in Solid Oxide Fuel Cells

Motivation 

Solid oxide fuel cells (SOFC) are new generation electrochemical devices that convert the chemical energy of a fuel directly into electrical energy with an additional amount of valuable heat energy. They can also be considered to be an environmentally friendly technology, depending on how the fuel is processed. Since the energy conversion is totally electrochemical and does not contain any other intermediate energy conversion steps, the electrical efficiency of SOFCs is relatively higher than similar mature technologies such as internal combustion engines. SOFCs may operate at very high temperature (600~1000°C) depending on the electrolyte material[1]. Specifically, reversible solid oxide cells (R-SOCs) can operate in both fuel cell mode and electrolysis mode. Due to their high efficiency, high-temperature operation, and versatility, R-SOCs exhibit potential advantages in various application scenarios[2].

Large internal-strain gradients caused by the mismatch in thermal expansion behavior between different fuel cell components are the main cause of this instability, which can lead to cell degradation, delamination or fracture[3]. The impact factors include the elastic, elastoplastic, creep strain material behavior, and mechanical constraints.[4] Various phenomena affecting cell performance have been identified, including delamination and cracking, Cr poisoning, grain coarsening, Ni redistribution in the Ni-YSZ electrode, secondary phase formation, etc. Among these mechanisms, electrode delamination and cracking, with more possible severe damage to cell life/operation than other mechanisms, is one of the most common irreversible modes of cell performance degradation[5].

Project goals

Multiphysics and multiscale modeling are essential for investigating the mechanisms and impacts of interfacial delamination. The doctoral project would be divided into three parts:

1. Probabilistic prediction of interfacial delamination in SOFC

2. Operational optimization strategies for mitigating delamination in SOFC

3. Mode-dependent interfacial delamination in R-SOC

References

[1]      Timurkutluk B, Timurkutluk C, Mat MD, Kaplan Y. A review on cell/stack designs for high performance solid oxide fuel cells. Renewable and Sustainable Energy Reviews 2016; 56:1101–21. doi.org/10.1016/J.RSER.2015.12.034.

[2]      Yang Y, Lei J, Huang X, Liao Z, Liu Y, Tu Z. Recent Development in Reversible Solid Oxide Fuel Cells: Theory, Integration and Prospective. ChemElectroChem 2024; 11:e202300593. doi.org/10.1002/CELC.202300593.

[3]      Zhang Y, Chen B, Guan D, Xu M, Ran R, Ni M, et al. Thermal-expansion offset for high-performance fuel cell cathodes. Nature 2021; 591:246–51. doi.org/10.1038/s41586-021-03264-1.

[4]      Peksen MM. Exploring the thermomechanical and dynamical mode switch transition of a reversible solid oxide cell. Int J Hydrogen Energy 2024; 81:353–70. doi.orghttps://doi.org/10.1016/j.ijhydene.2024.07.269.

[5]      Yang T, Fan Y, Liu J, Finklea H, Lee S, Guan B, et al. Multiphysics modeling of SOFC performance degradation caused by interface delamination and active layer cracking. Int J Hydrogen Energy 2022; 47:41124–37. doi.org/10.1016/J.IJHYDENE.2022.09.194.