Single-step fully 3D printed and co-sintered solid oxide fuel cells

The application of additive manufacturing technologies for the fabrication of functional ceramics has exhibited extraordinary potential for revolutionizing conventional manufacturing routes of electrochemical energy generators. The incorporation of 3D printing into the production strategy of Solid Oxide Cells (SOCs) allows their geometrical complexity to be increased through the hierarchical design of the systems, while simultaneously optimizing the ceramic manufacturing process, minimizing the upfront investment, and augmenting the manufacturing efficiency owing to the reduction in production steps. In this regard, the elaboration of multi-material 3D printing for the fabrication of entire SOC devices is required to achieve a fully automated production process. The current work presents and discusses the main technological and material challenges for the development of self-supported Solid Oxide Fuel Cells (SOFCs) fabricated in a single step by using hybrid multi-material 3D printing. The results on the fabrication of complete self-supported SOFCs are here presented with special attention to the most critical steps: the hybridization of stereolithography and robocasting 3D printing technologies and the co-sintering of a multilayered ceramic device. The electrochemical characterization of the printed and co-sintered cells validates the innovative approach, reaching a remarkable maximum power density above 250 mW cm-2 at 950 degrees C. This result, together with the developed hybrid technology, represents a step forward for further digitalization of the functional ceramic device manufacturing, more specifically, the SOC manufacturing process, leading to the fabrication of fully 3D printed monolithic SOFC stacks. The capabilities of hybrid multi-material additive manufacturing to produce entire self-standing SOFC devices have been proved in just two stages, 3D printing and co-sintering.