Effect of thermophysical properties of perovskite electrolytes on intermediate temperature SOFC

Solid oxide fuel cell (SOFC) has captured significant interest and the electrolyte material is the key during operating. The present work introduces a series of intermediate temperature perovskite materials regarding of synthesis and characterization method. Corresponding thermophysical properties including thermal diffusivity, specific heat and thermal conductivity were determined at relevant temperature range. The result shows that thermal diffusivity has a stable tendency for the intermediate temperature electrolytes materials; Ba 3 NbMoO 8.5 has the highest specific heat and BaSc 0.8 MoNb 0.2 O 2.8 has the highest thermal conductivity at 873 K. Besides, a 3-D model is established including transient state and steady state. After combining intermediate temperature electrolyte materials with different thermophysical properties, it is found that the maximum temperature gradient and thermal shock exist at switching time ( t = 600 s) and the tendency are controversial for each other. Besides, after comparing different supported structure of SOFC, a systematic selection strategy is provided for IT-SOFC application. Cathode-supported structure SOFC is an ideal choice for long term usage, which has a low temperature gradient; whereas electrolyte-supported structure with Na 0.5 Bi 0.5 TiO 3 electrolyte is beneficial to quick start-up system, which has the lowest thermal shock.