Study on innovative large-area ceramic proton conducting cell industrialisation

In the next incoming years, it is reasonable to expect tremendous changes in the energetic scenario, the intensification of the climate crisis makes necessary strong and rapid transition towards a more sustainable world. Proton conductive cells, PCCs, can represent a possible and valid solution in the future to help a greener energy transition, in particular they rely on already well known and develop technologies, such as PEMs and SOCs, but PCCs combine their major pros, allowing to reach high efficiency at lower operating temperature, simplifying the management of the stack and reducing the impact of possible degradation mechanism. In the last years, the attention for PCCs has grown exponentially, with several studies focused on the development of new materials, long-term stability test, reversible operations, and the possibility to be coupled with different fuels. The research on PCCs is widely supported by a constant interest on hydrogen, that at the moment is not only supported at university level, but also at industrial ones, with several companies believing on the potential role of hydrogen in the future energy market. This thesis was possible thanks to the collaboration of Politecnico di Torino and ELCOGEN, leader in the field of SOCs production, aiming to prove the feasibility of manufacturing large-scale cell by using methodologies widely employed in the industrial sector. No economic analysis was conducted, however, in the various steps, attention was paid to cost-effective strategies that can guarantee reliable results for large volume production. The cells structure it is based on the most popular configuration of anode supported cell, that guarantee better mechanical and electro-chemical performance, furthermore four different electrolytes were tested to understand potential advantages and drawback for future works: BCZY72 was synthesized on site using a wet-chemical route, by XRD analysis a clear unique phase was reported, while BZCYYb711 and BZCY72 were purchased from @Kceracell, the last electrolyte tested it is made by coupling BZCY72 with ZnO as sintering aid to improve the densification process. The fuel electrode is made of three different layers, a pure NiO contact on the bottom, a thick green tape realized by tape casting, using NiO, BZCY72 and graphite as pores former, on the top was printed an active layer, using an equal amount in mass of NiO and BZCY72. The cells were then completed by printing the electrolyte layer. During this project, different sintering profiles have been evaluated to understand the most suitable strategy for the materials involved. The samples realized with BCZY72 altrough did not sintered well at 1400°C regardless the dwell time, they kept a flat surface and did not show any sign of chemical reaction on the surface, while for ELE-B the results are more conflictual, at 1400°C the samples were dense, however the excessive shrinkage deformed the surface, making them useless for further steps. ELE-C and ELE-D did not provide any promising result, with clear sign of phase decomposition at high temperature and chemical instability. From ELE-A cells was possible to obtain five circular half-cells with a diameter of 45mm, these samples were completed by applying a single layer for both the composite cathode, BSCF-BZCYYb, and the pure contact, BSCF.