Temperature and reactive current distributions in microtubular solid oxide electrolysis cells

A two-dimensional tubular model of a cathode supported microtubular solid oxide electrolysis cell (SOEC) was developed in order to investigate the temperature distribution within the cell during high-temperature steam electrolysis. High-temperature steam electrolysis using SOECs allows for highly efficient hydrogen generation, because the heat from the overpotential can be recycled in the form of a heat source for the electrolysis reaction. However, to improve the durability and strength of the components, an understanding of the temperature distribution of the cell is essential, because heat absorption during electrolysis reaction leads to complex temperature distributions. The current density-voltage curves obtained using the above-mentioned model were in good agreement with the experimental ones. The calculated and measured temperature distributions indicated that the distribution in microtubular SOECs is a nonuniform one and suggested that the current-collecting positions strongly affect the temperature and reaction distributions under the conditions used herein.