Additive manufacturing of solid oxide fuel cells. A comprehensive review of patent literature

The solid oxide fuel cell (SOFC) technology has significant potential to become a large-scale, environmentally friendly solution for electricity generation, but realizing this goal hinges on advancements in performance and manufacturing. To succeed in this intent, additive manufacturing (AM) is considered a promising option. This study provides a comprehensive review of patent literature about the AM of SOFC, identifying and comparing goals, implemented AM strategies and clusters of intersections among them. Compared to previous reviews, limited to the scientific literature, some new solutions characterized by unknown goals and AM strategies have been identified. Most common clusters are: lattice structure optimization in SOFC electrodes to optimize porosity solving a compromise between gas diffusion, ionic conductivity and mechanical resistance; the printing of thin walls and self-supporting structures to build complex fuel channels; graded or 3D interface between electrolyte and electrode to improve the ionic flow. Patent bibliometrics and discussion of the results show how industrial and scientific research are patenting ideas rather than solutions ready to be implemented about the AM of the SOFC. The results of this review may be useful to industries interested in patent intelligence on the topic, as well as to researchers to understand which lines of research arouse greater economic interest.