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In recent years, the technology readiness level of next-generation lithium-sulfur (Li/S) batteries has shifted from coin cell to pouch cell dimensions. Promising optimizations of the electrodes, electrolytes, active materials, and additives lead to improved performance and cycling stability. However, new challenges arise with the pouch cell design and engineering (including electrode stacking and electrolyte filling), which influence the mechanistic processes of the cell. This study presents an unprecedented multimodal operando investigation of Li/S batteries on a pouch cell level and provides an inside view of material transformations during battery cycling, using X-ray radiography, electrochemical impedance spectroscopy, and spatially resolved temperature monitoring. With the comparison of two different electrolytes, new experimental details about sulfur and lithium sulfide deposition and dissolution processes are revealed and related to electrolyte and temperature distribution. Operando impedance measurements on monolayer pouch cells yield a clear correlation of electrochemical and macroscopic radiographic observations. Understanding the monolayer cells’ behavior represents an optimal foundation for further studies on multilayer pouch cell prototypes and demonstrators with the developed operando setup. Herein the proof of principle for correlated measurement methods on pouch cell level is shown, and the experimental proof of concept for sulfur crystal suppression in sparingly solvating electrolyte is visualized.

The understanding of dynamic processes in Li metal batteries is an important consideration to enable the full capacity of cells to be utilised. These processes, however, are generally not directly observable using X ray techniques due to the low attenuation of Li; and are challenging to visualise using neutron imaging due to the low temporal resolution of the technique. In this work, complementary X ray and neutron imaging are combined to track the dynamics of Li within a primary Li SOCl2 cell. The temporal challenges posed by neutron imaging are overcome using the golden ratio imaging method which enables the identification of Li diffusion in operando. This combination of techniques has enabled an improved understanding of the processes which limit rate performance in Li SOCl2 cells and may be applied beyond this chemistry to other Li metal cells.

The ability to track electrode degradation, both spatially and temporally, is fundamental to understand performance loss during operation of lithium batteries. X ray computed tomography can be used to follow structural and morphological changes in electrodes; however, the direct detection of electrochemical processes related to metallic lithium is difficult due to the low sensitivity to the element. In this work, 4 dimensional neutron computed tomography, which shows high contrast for lithium, is used to directly quantify the lithium diffusion process in spirally wound Li SOCl2 primary cells. The neutron dataset enables the quantification of the lithium transport from the anode and the accumulation inside the SOCl2 cathode to be locally resolved. Complementarity between the collected neutron and X ray computed tomographies is shown and by applying both methods in concert we have observed lithium diffusion blocking by the LiCl protection layer and identified all cell components which are difficult to distinguish using one of the methods alone

We present non destructive and non invasive in operando X ray tomographic investigations of the charge and discharge behavior of rechargeable alkaline manganese RAM batteries Zn MnO2 batteries . Changes in the three dimensional structure of the zinc anode and the MnO2 cathode material after several charge discharge cycles were analyzed. Battery discharge leads to a decrease in the zinc particle sizes, revealing a layer by layer dissolving behavior. During charging, the particles grow again to almost their initial size and shape. After several cycles, the particles sizes slowly decrease until most of the particles become smaller than the spatial resolution of the tomography. Furthermore, the number of cracks in the MnO2 bulk continuously increases and the separator changes its shape. The results are compared to the behavior of a conventional primary cell that was also charged and discharged several times

International audience; Gorgonopsia is one of the major clades of non-mammalian synapsids, and includes an array of large-bodied carnivores that were the top terrestrial predators of the late Permian. Most research on the clade has focused on these largest members; small-bodied gorgonopsians are relatively little-studied. Here, we redescribe a small gorgonopsian skull (MB.R.999) from the late Permian (Tropidostoma Assemblage Zone) of South Africa on the basis of neutron and synchrotron CT reconstructions, which yield new data on internal cranial morphology in Gorgonopsia. Because of the largely undistorted nature of MB.R.999, we were also able to reconstruct unossified areas such as the brain endocast and the otic labyrinth. MB.R.999 can be referred to the taxon Cynariops robustus based on its general skull proportions, postcanine tooth count, preparietal morphology, and vomerine morphology. We refer additional small gorgonopsian specimens from the Victoria West area to Cynariops robustus, and consider Cynarioides grimbeeki and Cynarioides laticeps to be synonymous with C. robustus. Inclusion of Cynariops in a phylogenetic analysis of Gorgonopsia recovers it within a large clade of African taxa, more closely related to Lycaenops and rubidgeines than Eriphostoma or Gorgonops.

The potentials of incoherent X ray scattering Compton tomography are investigated. Imaging materials of very different density or atomic number at once is a perpetual challenge for X ray tomography or radiography, in general. In a basic laboratory set up for simultaneous perpendicular Compton scattering and direct beam attenuation tomographic scans are conducted by single channel photon counting. This results in asymmetric distortions of the projection profiles of the scattering CT data set. In a first approach corrections of Compton scattering data by taking advantage of rotational symmetry yield tomograms without major geometric artefacts. A cylindrical sample composed of PE, PA, PVC, glass and wood demonstrates similar Compton contrast for all the substances, while the conventional absorption tomogram only reveals the two high order materials. Comparison to neutron tomography reveals astonishing similarities except for the glass component without hydrogen . Therefore, Compton CT bears the potential to replace neutron tomography, which requires much more efforts.

Though comprehensive knowledge of water status and water flow are important prerequisites for plant in many aspects of modern plant science truly non-destructive methods for the in-situ study of water transport are rare. Advanced imaging methods such as Magnetic Resonance Imaging (MRI) or Cold Neutron Radiography (CNR) may be applied to fill this gap. In CNR strong interaction of cold neutrons with hydrogen provides a high contrast even for small amounts of water. The combination of CNR with the low-contrast tracer D2O allows the direct visualisation of water flow and the calculation of water flow rates in plants with a high resolution at the tissue level. Here, we give a general introduction into this method, describe their latest developments, report about studies applying neutron radiography in plant science and provide most recent results of our experiments in this field.

Conservation of cultural heritage is extremely important not only from a cultural point of view, but also from a practical one. It is our duty to pass on to future generations the cultural heritage left to us by our ancestors. Wood is one of the most common materials used to generate works of art which are in a state of constant change and/or deterioration. In order to optimize the knowledge of artworks together with their conservation, it is necessary to use the most advanced scientific and technological tools. In the following paper, we will show the tomographic results which can be achieved by application of complementary techniques based on the combined use of X-ray and neutron radiography as structural probes.

In this chapter we give a brief overview of neutron based analytical investigations applied to study archaeological ceramics, and different types of stones. Since the vast majority of archaeological objects are made of ceramics and various stones—all are of geological origin—, one of the key objectives of these studies to determine the origin of raw material. This research is called provenance research, and a wide range of neutron based methods are applicable in it. Following a very basic, user-oriented description of the methods, we introduce examples from our everyday practice. The examples are about provenance of prehistoric stone tools, about the sources of 4th–3rd c. B.C. millennium limestone idols found in the South of Portugal, as well as about the characterization of 15th–16th c. A.D. Inka pottery. A very unique application of combined neutron techniques was aimed to determine the inner content of an Eighteenth Dynasty Egyptian sealed vessel. In addition, investigations of samples from different epochs and characterization of marbles are presented.