Contents: This dataset contains 3D image stacks acquired with FIB-tomography from Ni-YSZ cermet anodes for Solid Oxide Fuel Cells (SOFC). The data was collected from three different Ni-YSZ anodes (fine-, medium- and coarse-grained). Each of these anodes was investigated first in pristine state (after sintering and reduction) and then also in degraded state (after exposure to 8 redox cycles). The 6 tomographs are then presented as stacks of 2D-tiff-images in 2 different versions: as gray-scale images (raw data) and as segmented images (Ni=white, YSZ=gray and pores=black). In total this gives 12 image stacks. Further details, such as the voxel resolutions and image window sizes are listed in the downloadable excel file (2_3D_Data_Info.xlsx). Scientific Context: The microstructures of the cermet anodes were investigated for the purpose of optimizing the anode performance, which depends on effective transport properties (i.e. conductivity of ions in YSZ and of electrons in Ni, as well as diffusivity of fuel/gas in the pores). Furthermore the anode performance also depends on the catalytic/electrochemical activity (i.e. Ni-surface area and three phase boundary length TPBL). The microstructure characteristics have a strong influence on effective properties, electrochemical activity and associated anode performance. Furthermore, microstructure degradation (e.g. by Ni-coarsening) may lead to performance loss over time. Hence, the investigations focus on a fundamental, quentitative understanding of the relationships between microstructure characteristics and effective properties. The study reveals quantitative descriptions of all relevant microstructure characteristics (porosity, tortuosity, constrictivity, surface/interface areas, TPBL) and of the corresponding effective transport porperties (electric and ionic.conductivities). The corresponding anode performance was characterized by impedance spectroscopy. The quantitative results of the microstructure investigation were published in: Pecho et al 2015a (doi:10.3390/ma8095265), Pecho et al 2015b (doi:10.3390/ma8105370), Holzer et al 2013 (doi: 10.1016/j.jpowsour.2013.05.047), Holzer et al 2011a (doi: 10.1016/j.jpowsour.2010.08.017) and Holzer et al 2011b (doi: 10.1016/j.jpowsour.2010.08.006).

Funding: - SFOE/BfE: SOF-CH (2010-2013): Enhancing the Lifetime of SOFC stacks in Switzerland (Grant SI 500'084) - Swiss National Science Foundation SNSF: Relationships between 3D topology and kinetics in mixed conducting electrodes for SOFC (Grant SNF 200021_135270) ZHAW project data base: https://www.zhaw.ch/en/search/?source=project&language=en Author's Personal Homepages: https://www.zhaw.ch/en/about-us/person/holz/ https://www.zhaw.ch/index.php?id=9118 https://www.researchgate.net/profile/Lorenz_Holzer https://scholar.google.com/citations?hl=de&user=9Wr7IccAAAAJ