Tubular SOFC air electrode ohmic overpotential: Parametric and exergy study

Highlights: • Increase the oxygen vacancy concentration to 0.2 increases the exergy efficiency. • Increase the diffusion coefficient to 0.00005 cm² s⁻¹ enhances exergy efficiency. • Have the cathode with porosity between 0.2 and 0.4 enhances exergy efficiency. • Have the cathode with a tortuosity between 1 and 1.5 4 enhances exergy efficiency. - Abstract: The SOFC efficiency still can be improved by reducing the overpotential losses, However to battle this issue, band gap engineering of SOFC material needs to be considered. In this work, we analyzed the effect of various materials parameters and environmental conditions on the performance of SOFC. To maintain the optimum performance for SOFCs and to enhance the energy and exergy efficiency in practical application environments, it is recommended to have the oxygen vacancy concentration at 0.2, diffusion coefficient at 0.00005 cm² s⁻¹, cathode porosity of 0.3, tortuosity of 1.5, chemical capacitance at 2.7 F cm⁻², the conductor electrolyte interface at 0.0004 cm, surface area of the porous conductor at 50,000 cm² cm⁻³, and operating temperature of 1000 °C.