title: Multi-Scale Correlative Tomography of a Li-Ion Battery Composite Cathode.
abstract: Focused ion beam/scanning electron microscopy tomography (FIB/SEMt) and synchrotron X-ray tomography (Xt) are used to investigate the same lithium manganese oxide composite cathode at the same specific spot. This correlative approach allows the investigation of three central issues in the tomographic analysis of composite battery electrodes: (i) Validation of state-of-the-art binary active material (AM) segmentation: Although threshold segmentation by standard algorithms leads to very good segmentation results, limited Xt resolution results in an AM underestimation of 6 vol% and severe overestimation of AM connectivity. (ii) Carbon binder domain (CBD) segmentation in Xt data: While threshold segmentation cannot be applied for this purpose, a suitable classification method is introduced. Based on correlative tomography, it allows for reliable ternary segmentation of Xt data into the pore space, CBD, and AM. (iii) Pore space analysis in the micrometer regime: This segmentation technique is applied to an Xt reconstruction with several hundred microns edge length, thus validating the segmentation of pores within the micrometer regime for the first time. The analyzed cathode volume exhibits a bimodal pore size distribution in the ranges between 0-1 μm and 1-12 μm. These ranges can be attributed to different pore formation mechanisms.
authors.affiliation: Laboratory for MEMS Applications, IMTEK Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg, Germany.
authors.forename: Riko
authors.initials: R
authors.lastname: Moroni
authors.affiliation: MEET Battery Research Center, Institute of Physical Chemistry, University of Münster, Corrensstraße 46, 48149 Münster, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Börner
authors.affiliation: Laboratory for MEMS Applications, IMTEK Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg, Germany.
authors.forename: Lukas
authors.initials: L
authors.lastname: Zielke
authors.affiliation: MEET Battery Research Center, Institute of Physical Chemistry, University of Münster, Corrensstraße 46, 48149 Münster, Germany.
authors.forename: Melanie
authors.initials: M
authors.lastname: Schroeder
authors.affiliation: MEET Battery Research Center, Institute of Physical Chemistry, University of Münster, Corrensstraße 46, 48149 Münster, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Nowak
authors.affiliation: MEET Battery Research Center, Institute of Physical Chemistry, University of Münster, Corrensstraße 46, 48149 Münster, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Winter
authors.affiliation: Helmholtz Centre Berlin, Hahn-Meitner-Platz 1, 14109 Berlin, Germany.
authors.forename: Ingo
authors.initials: I
authors.lastname: Manke
authors.affiliation: Laboratory for MEMS Applications, IMTEK Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg, Germany.|Hahn-Schickard, Georges-Koehler-Allee 103, 79110 Freiburg, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Zengerle
authors.affiliation: Laboratory for MEMS Applications, IMTEK Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg, Germany.|FIT, University of Freiburg, Stefan-Meier-Straße 21, 79104 Freiburg, Germany.
authors.forename: Simon
authors.initials: S
authors.lastname: Thiele