Overcoming Durability Limits in SOEC Stacks Through Mass Transfer Control (May 21, 2026)

Professor Hong Jong-seop’s research team (including Master’s graduate Lim Jang-hyun and Ph.D. graduate Lee Woo-seok) has developed a mass-transfer-controlled stack structure designed to overcome the durability limitations of solid oxide electrochemical cell (SOEC) stacks through collaborative research with Hyundai Motor Company and the Korea Institute of Science and Technology (KIST). The research team focused on the issue of accelerated microstructural degradation of the Ni–YSZ fuel electrode caused by the concentration of water vapor and current density at the fuel inlet within commercial large-area SOEC stacks. To address this, they introduced a slit-sheet structure patterned with micro-slits to uniformize fuel supply, diffusion, and reaction distribution. Through long-term severe operation, three-dimensional multiphysics simulations, and FE-SEM post-analysis, the team demonstrated that this structure mitigates the high-humidity, high-reactivity environment at the inlet and suppresses nickel depletion, coarsening, and damage to the electrical interconnection network. In particular, the optimized stack reduced the degradation rate over 500 hours from 8% to 3% compared to conventional stacks and demonstrated stable durability even during long-term operation exceeding 2,000 hours. This study is significant in that it presents a practical and scalable design strategy capable of improving the durability of high-temperature water electrolysis systems by controlling transport phenomena within the stack without requiring changes to electrode materials. The findings of this study were published in Joule, a prestigious international journal in the energy field (Impact Factor of 37.1 as of 2025, ranked in the top 1.3% of the JCR Energy & Fuels category).

Link to the related paper: https://doi.org/10.1016/j.joule.2026.102485