Solid oxide electrolysis cells (SOECs) are a promising technology for high-efficiency hydrogen production using renewable electricity, offering a zero-CO₂-emission pathway toward decarbonization. However, SOEC stacks operate under harsh conditions, such as high temperatures (600–800 °C), redox atmospheres, and mechanical loads during stacking, which may cause cell fracture, delamination, or seal damage. To ensure durability and commercial viability, both electrochemical performance and mechanical reliability must be addressed. This study investigates the influence of rib geometry and thermal cell deformation on gas flow, electrochemical behavior, and mechanical stress through multiphysics simulations. Three rib configurations—linear, circular, and hexagonal—were evaluated under equal contact area ratios. Flow analysis showed that the linear rib achieved the highest average velocity, lowest pressure drops, and no reverse flow. In contrast, the circular and hexagonal ribs induced local gas stagnation and reverse flow, resulting in higher steam consumption per unit length. Electrochemical analysis revealed that the linear structure also exhibited the highest reaction efficiency. However, normalized current density distributions along the flow direction were similar across all geometries, indicating that the overall electrochemical performance differences were moderate. Mechanical analysis showed that stress concentrations occurred near the oxygen electrode side regardless of rib shape. Furthermore, in thermally deformed cells, uniaxial compression led to localized stress amplification, emphasizing the importance of cell flatness. These findings suggest that optimizing rib geometry and minimizing cell warpage are both critical for enhancing SOEC stack performance and mechanical stability.
KOJIMA et al. (Wed,) studied this question.