A novel hexagon-shaped interconnector for protonic ceramic electrolysis cells for large-scale green hydrogen production

Protonic ceramic electrolysis cells (PCECs) are the next generation of electrolysis technology for large-scale green hydrogen due to their lower power consumption but higher hydrogen production rate, compared with conventional alkaline electrolysis cells. The practical performance of PCEC stacks is still not satisfactory, and one key reason is the highly non-uniform distribution of H2O over large PCECs. To address the challenge of PCECs for practical application, a novel PCEC stack design with a hexagon-shaped interconnector is proposed and evaluated by using a comprehensive 3D numerical model. It is found that the novel interconnector can achieve higher uniformity indices for H2O and O2 by 11.7% and 46.2%, respectively. An overall performance index, integrating seven metrics, effectively identifies the hexagon-shaped interconnector with an 80 μm baffle thickness as the top performer. The methodology employed to derive this index proves to be a valuable tool for comprehensive performance evaluation, particularly in studies involving multiple metrics. This research lays a robust foundation for the optimisation of PCEC performance through an innovative interconnector design and advanced evaluation techniques.