Investigation of the filling of a porous ceramic matrix by molten salts using nano X-ray tomography

High-resolution nano X-ray computed tomography (nano-XCT) was used to investigate the process of infiltration of a Molten Carbonate Fuel Cell (MCFC) matrix by liquid electrolyte. A ceramic matrix made of a LiAl 2O3 powder was infiltrated by a liquid electrolyte during the start-up process of the MCFC. Nano-XCT extends the state-of-the art techniques for characterizing the morphology of the ceramic matrix and for the study of the penetration kinetics with electrolyte. Quantitative morphology analysis using high-resolution nano-XCT provides 3D information for each MCFC component nondestructively. The spatially resolved volume fraction of the molten electrolyte calculated from the 3D XCT data is used for simulation and to improve MCFC performance. Based on the results obtained, a new start-up procedure is proposed for a single MCFC. This procedure is consistent with the morphology changes which occur during the melting process inside the ceramic matrix.