The vacuum plasma spraying (VPS) process allows the production of very thin solid oxide fuel cells (SOFC) with low internal resistances. This enables the reduction of the cell operating temperature without a significant decrease in power density. Consequently, the long-term stability can be improved and low-cost materials can be used. Different material combinations and spray parameters were applied to develop completely plasma sprayed cells with thin gas tight YSZ or ScSZ electrolyte as well as porous YSZ-Ni- or ScSZ-Ni fuel electrode and (La,Sr)MnO_3-YSZ- or (La,Sr)MnO_3-ScSZ air electrode layers onto porous metallic substrates. The development of the plasma sprayed cells with a thickness of approximately 100 μm requires an overall electrical and electrochemical characterisation process of the single layers and of the completely plasma sprayed cell assembly. The paper focuses on the results of 4-point electrical conductivity measurements, I-V-measurements, impedance spectroscopy and long-term operation at constant current load. Cells with different sizes and material combinations on different porous metallic substrates were characterised. The individual resistances of the different cell components, such as polarisation of the electrodes and diffusion polarisation were determined, especially at different operating temperatures. High power density cells with large active areas enable the assembling of stacks which can be operated at reduced temperature of about 750°C-800°C.
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