A fully coupled electro-thermo-mechanical CFD model is developed and applied to illuminate the crucial factors influencing the overall performance of a solid oxide electrolysis cell (SOEC), particularly the configuration and geometry parameters of its inter-connector (IC), comprising ribs and channels. Expanding on a selected width ratio of 4:3, the gradient ribs/channels are further investigated to assess electrochemical and thermo-mechanical performance. It is elucidated that, while maintaining constant maximum temperature and thermal stress levels, employing a non-regular geometry IC with gradient channels may yield a 30% enhancement in hydrogen production. These nuanced explorations illuminate the complex interplay between IC configuration, thermal stresses, and electrolysis efficiency within SOECs.