aIn the literature, it is widely claimed that during the initial period of Fischer-Tropsch synthesis liquid higher hydrocarbons fill catalyst pores completely, at least for temperatures of less than 250°C at a typical pressure of about 2 MPa. This leads to diffusional restrictions in the porous network for particles with a size for industrial fixed-bed operation (> 1 mm), whereby catalyst effectiveness and product selectivity are strongly affected. However, under industryally relevant reaction conditions, our experimental and theoretical investigations on the interplay of reaction and diffusion in cobalt catalyst particles reveal that the pores are only partly filled with liquid higher hydrocarbons even at a very long time on stream of months or more for a chain growth probability below about 0.8. Experiments were conducted in a magnetic suspension balance using particles of technical size (dp = 3 mm), and a mathematical model was developed describing quite accurately the formation, vaporization and accumulation of liquid products and their C-number distribution in the porous particle.

Li-ion cells of the industrially-relevant formats PHEV1 (prismatic), multi-layer pouch, and 21700 (cylindrical) are directly compared by experiments for the first time. All three cell formats were reproducibly built on pilot-scale with the same anode (graphite), cathode (NMC622), separator, and electrolyte allowing a direct comparison. The main differences between these formats are their capacities (24.6 Ah, 2.2 Ah, 2.3 Ah), volume/surface ratios, as well as tab and the jellyroll/stack configurations (flat-wound, stacked, wound). The comparison involves voltage curves during formation (0.1 C), discharge rate capability (0.5 C−3 C), heating behaviour, cell impedances, geometrical properties such as electrode curvatures and tab configurations, as well as comparison with coin half cells with anode and cathode vs Li counter electrode. The data are put into context with commercial and pilot-line built cells from other studies.

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During the production process of lithium‐ion battery cells, the filling, which consists of dosing and wetting steps, of the cell and its components with an electrolyte liquid is important for the quality and costs of the final product. The cell format as a combination of housing and cell arrangement not only determines the type of filling process but also influences the distribution of the electrolyte within the cell. The cell format also has an influence on the wetting state as a function of time. Herein, in situ neutron radiography is used to analyze the filling process of two different cell types – pouch cells with a z‐folded stack and hardcase cells with a flat wound roll. The results are then analyzed and transferred to other common cell formats to identify a fillable cell design and format‐dependent process improvement possibilities to enable faster processing.

We demonstrate the feasibility of investigating periodically driven magnetization dynamics in a scanning electron microscope with polarization analysis based on spin-polarized low-energy electron diffraction. With the present setup, analyzing the time structure of the scattering events, we obtain a temporal resolution of 700 ps, which is demonstrated by means of imaging the field-driven 100 MHz gyration of the vortex in a soft-magnetic FeCoSiB square. Owing to the efficient intrinsic timing scheme, high-quality movies, giving two components of the magnetization simultaneously, can be recorded on the time scale of hours.

Li‐ion battery cells on the basis of Si‐containing anodes suffer from their large volume expansion of up to 300%, impeding their extensive application in the automotive field. Herein, the synthesis of a Si‐rich Si/C composite is introduced. The implemented porosity of the composite has a buffering effect on the Si volume changes during cycling. The scalability of the material from lab‐scale to industrial‐scale batch sizes as well as from coin cell (<5 mAh), to pouch cell (≈0.75 Ah), and to prismatic (PHEV) cells (≈26 Ah) is demonstrated. The performance of the pouch cells and PHEV cells is further improved by cycling under an external mechanical pressure. The irreversible swelling of the pouch and the PHEV cells stays below 6% during cycling. Reproducible aging and swelling behavior of different cell types is observed and investigated in detail. The low irreversible volume increase is confirmed by X‐ray computer tomography (CT) measurements of the PHEV cells before and after cycling.

The domain structure and its changes with temperature were investigated for an epitaxial NdCo 5 thin film with in-plane texture in which a spin-reorientation transition takes place from the easy c-axis via the easy cone to the easy plane. Scanning electron microscopy with polarization analysis reveals a transition from a two-domain state at temperatures above 318 K via a four-domain state back to a 90 • -rotated two-domain state at temperatures below 252 K. The transition temperatures correspond well to those determined by global magnetization measurements. The magnetization configuration at the three different regimes of magnetic anisotropy and its transition with temperature were analysed in detail. From the local measurements, the spin-reorientation angle and the magnetocrystalline anisotropy constants of first and second order were derived. Gesellschaft phases the individual contributions of the cobalt-and the RE metal sublattices to the magnetocrystalline anisotropy lead to a temperature-driven spin-reorientation transition (SRT). This is due to the fact that the anisotropy of the RE sublattice decreases strongly with increasing temperature owing to the weak RE-RE exchange interaction, J RR , whereas the Co sublattice anisotropy is maintained even at high temperatures (J CoCo J RR ). At higher temperatures, the uniaxial anisotropy of the Co sublattice (parallel to the crystallographic c-axis) will always dominate, while a possible basal plane anisotropy of the RE subsystem may take over at lower temperature. This leads to a temperature-driven change in the easy magnetization direction known as SRT. Upon cooling down, an SRT with an opening of a magnetic easy cone takes place, e.g. in PrCo 5 , where it was investigated in bulk [1][2][3][4] as well as in epitaxial thin film samples [5]. A complete SRT from a magnetic easy c-axis via a magnetic easy cone to a magnetic easy plane in the ab-plane of the hexagonal crystal is observed in NdCo 5 . Additionally, in the easy basal plane the a-axis is energetically preferred over the b-axis [2,[6][7][8]. This thirdorder anisotropy effect is, however, not investigated in the present study. Like in the case of PrCo 5 , for NdCo 5 the SRT was initially observed in bulk samples [2,6,7,[9][10][11][12], where it takes place between 280 and 240 K. We recently succeeded in preparing epitaxial NdCo 5 films on MgO(110) and Al 2 O 3 (0001) substrates with an in-plane and out-of-plane texture, respectively [13,14]. For the in-plane samples the transition temperatures were determined as 310 and 255 K, while for the out-of-plane samples the transitions were qualitatively confirmed, but the exact temperatures were not accessible due to the influence of the shape anisotropy. For the in-plane textured film on MgO(110) investigated here, a sketch of the temperaturedependent easy axis of magnetization and the alignment of the crystal structure with respect to the substrate is shown in figure 1. Due to the shape anisotropy of a thin film, the different possible orientations along the surf...