Hybrid-3D printing of symmetric solid oxide cells by inkjet printing and robocasting

When processed using state-of-the-art techniques, Solid Oxide Cells (SOCs) fabrication (e.g. tape casting) requires many fabrications steps. Recently Additive Manufacturing (AM) techniques have gained popularity to complement or substitute SOCs fabrication processes. AM allows the combination of different techniques to produce complete cells, minimising material waste while reducing the number of fabrication steps and improving their reliability. 3D printed symmetrical cells with composition LSM-YSZ/YSZ/LSM-YSZ were prepared by a robocasting and inkjet printing hybrid technology followed by a co-sintering step. Printability tests and rheological characterization have been made on the robocast LSM-YSZ slurries for the electrodes and on the water-based YSZ ink for inkjet printing to produce the dense electrolyte. This study presents the fabrication of complete cells with self-standing robocast electrodes combined with inkjet printed electrolytes and their co-sintering in one step. After co-sintering, the symmetrical cells were characterized by SEM-EDX, XRD and EIS. The microstructural analysis confirms the feasibility of the process and its reproducibility. The electrochemical characterization lead to an ASR value of ≈2.1 Ω cm² at 750 °C. These remarkable results demonstrate the potential of robocasting and inkjet printing for the fabrication of multi-material energy devices.