A versatile and robust process was developed for the fabrication of ceramic films in solid oxide fuel cells (SOFCs), allowing the microstructures of the films to be tailored from porous to dense. This nanoscale spray process was assisted by electrospray ionization and specific polymer additives such as polyvinyl pyrrolidone and polyvinyl butyral, and it provided a large degree of freedom for controlling the membrane microstructures of the cathode and electrolyte. The final spray-deposition-based SOFC cell, which consisted of a dense, thin electrolyte (thickness: similar to 4 mu m) and a crack-free porous cathode layer (thickness: similar to 10 mu m), exhibited notable reliability, an open-circuit voltage of similar to 1.11 V (approaching the theoretical value), and a maximum power density of similar to 805 mW/cm(2) at 650 degrees C, which is substantially higher than the power-generating performances of previously reported spray-deposition-based SOFCs.