Mathematical Model-Assisted Ultrasonic Spray Coating for Scalable Production of Large-Sized Solid Oxide Electrochemical Cells

Thinsolid oxide films are crucial for developing high-performancesolid oxide-based electrochemical devices aimed at decarbonizing theglobal energy system. Among various methods, ultrasonic spray coating(USC) can provide the throughput, scalability, quality consistency,roll-to-roll compatibility, and low material waste necessary for scalableproduction of large-sized solid oxide electrochemical cells. However,due to the large number of USC parameters, systematic parameter optimizationis required to ensure optimal settings. However, the optimizationsin previous literature are either not discussed or not systematic,facile, and practical for scalable production of thin oxide films.In this regard, we propose an USC optimization process assisted withmathematical models. Using this method, we obtained optimal settingsfor producing high-quality, uniform 4 x 4 cm(2) oxygenelectrode films with a consistent thickness of & SIM;27 & mu;min 1 min in a facile and systematic way. The quality of the filmsis evaluated at both micrometer and centimeter scales and meets desirablethickness and uniformity criteria. To validate the performance ofUSC-fabricated electrolytes and oxygen electrodes, we employ protonicceramic electrochemical cells, which achieve a peak power densityof 0.88 W cm(-2) in the fuel cell mode and a currentdensity of 1.36 A cm(-2) at 1.3 V in the electrolysismode, with minimal degradation over a period of 200 h. These resultsdemonstrate the potential of USC as a promising technology for scalableproduction of large-sized solid oxide electrochemical cells.