TY - JOUR A1 - Menga, D. A1 - Wagner, F. E. A1 - Fellinger, Tim-Patrick T1 - Life cycle of single atom catalysts: a Mo¨ssbauer study on degradation and reactivation of tetrapyrrolic Fe–N–C powders N2 - The degradation of a single-site atomically dispersed, model Fe–N–C powder catalyst with high activity is investigated using cryo-Mössbauer spectroscopy. The results indicate a degradation initiated by an Fe2+ to Fe3+ oxidation due to coordination of oxygen to tetrapyrrolic Fe–N4 sites at atmospheric conditions (change between characteristic doublets) before iron(III) oxide is formed (sextet). Thermal reactivation can be used to restore substantial catalytic activity of aged Fe–N–C powders. KW - Life cycle KW - Atom catalysts KW - Tetrapyrrolic Fe–N–C powders PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-586007 DO - https://doi.org/10.1039/d3mh00308f SN - 2051-6347 SP - 1 EP - 7 PB - Royal Society of Chemistry (RSC) AN - OPUS4-58600 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Menga, D. A1 - Wagner, F. E. A1 - Fellinger, Tim-Patrick T1 - Life cycle of single atom catalysts: a Mössbauer study on degradation and reactivation of tetrapyrrolic Fe–N–C powders N2 - The degradation of a single-site atomically dispersed, model Fe–N–C powder catalyst with high activity is investigated using cryo-Mössbauer spectroscopy. The results indicate a degradation initiated by an Fe2+ to Fe3+ oxidation due to coordination of oxygen to tetrapyrrolic Fe–N4 sites at atmospheric conditions (change between characteristic doublets) before iron(III) oxide is formed (sextet). Thermal reactivation can be used to restore substantial catalytic activity of aged Fe–N–C powders. KW - Single atom catalysts KW - Mössbauer study KW - Tetrapyrrolic Fe–N–C powders PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589352 DO - https://doi.org/10.1039/d3mh00308f VL - 10 SP - 5577 EP - 5583 PB - Royal Society of Chemistry AN - OPUS4-58935 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bates, J. S. A1 - Martinez, J. J. A1 - Hall, M. N. A1 - Al-Omari, A. A. A1 - Murphy, E. A1 - Zeng, Y. A1 - Luo, F. A1 - Primbs, M. A1 - Menga, D. A1 - Bibent, N. A1 - Sougrati, M. T. A1 - Wagner, F. E. A1 - Atanassov, P. A1 - Wu, G. A1 - Strasser, P. A1 - Fellinger, Tim-Patrick A1 - Jaouen, F. A1 - Root, T. W. A1 - Stahl, S. S. T1 - Chemical Kinetic Method for Active-Site Quantification in Fe-N‑C Catalysts and Correlation with Molecular Probe and Spectroscopic Site-Counting Methods N2 - Mononuclear Fe ions ligated by nitrogen (FeNx) dispersed on nitrogen-doped carbon (Fe-N-C) serve as active centers for electrocatalytic O2 reduction and thermocatalytic aerobic oxidations. Despite their promise as replacements for precious metals in a variety of practical applications, such as fuel cells, the discovery of new Fe-N-C catalysts has relied primarily on empirical approaches. In this context, the development of quantitative structure−reactivity relationships and benchmarking of catalysts prepared by different synthetic routes and by different laboratories would be facilitated by the broader adoption of methods to quantify atomically dispersed FeNx active centers. In this study, we develop a kinetic probe reaction method that uses the aerobic oxidation of a model hydroquinone substrate to quantify the density of FeNx centers in Fe-N-C catalysts. The kinetic method is compared with low-temperature Mössbauer spectroscopy, CO pulse chemisorption, and electrochemical reductive stripping of NO derived from NO2 − on a suite of Fe-N-C catalysts prepared by diverse routes and featuring either the exclusive presence of Fe as FeNx sites or the coexistence of aggregated Fe species in addition to FeNx. The FeNx site densities derived from the kinetic method correlate well with those obtained from CO pulse chemisorption and Mössbauer spectroscopy. The broad survey of Fe-N-C materials also reveals the presence of outliers and challenges associated with each site quantification approach. The kinetic method developed here does not require pretreatments that may alter active-site distributions or specialized equipment beyond reaction vessels and standard analytical instrumentation. KW - Active-Site Quantification PY - 2023 DO - https://doi.org/10.1021/jacs.3c08790 SP - 1 EP - 16 PB - ACS Publications AN - OPUS4-58889 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krug von Nidda, Jonas A1 - Fellinger, Tim-Patrick T1 - Current State of Research of Environmentally Friendly, Alternative Materials - Sodium-Ion-Batteries as an Example N2 - In order meet the anticipated future need for battery-based energy storage, it is essential to explore alternative systems beyond lithium-ion batteries. Sodium-ion batteries emerge as a promising option due to the abundance of readily available materials and the potential for reduced costs. T2 - 32. Sitzung Beraterkreis Technologie (BKT) CY - Cologne, Germany DA - 19.10.2023 KW - Sodium-ion-batteries PY - 2023 AN - OPUS4-58886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mehmood, Asad A1 - Fellinger, Tim-Patrick T1 - Ionothermal Template Transformation as a Sustainable Route Towards Carbon Electrodes in Energy Storage and Conversion N2 - Porous carbons with tuneable functionalities and morphologies have extensively been employed as electrode materials in a variety of electrochemical energy conversion and storage systems for instance in fuel cells and electrolysers as active catalysts and catalyst supports, and in secondary batteries as anode materials. Amorphous carbons with well-developed pore structures are of particular interest due to their superior mass-transport characteristics and remarkable charge storage capacities. T2 - Nano-Pak 2023, 2nd International Conference on Emerging Trends & Innovations in Nanotechnology CY - Lahore, Pakistan DA - 17.06.2023 KW - Ionothermal Template Transformation KW - Sustainable Route KW - Carbon Electrodes PY - 2023 AN - OPUS4-58897 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Structure-Performance Relations of PGM-free Electrocatalysts for PEM Fuel Cells N2 - Proton-exchange membrane fuel cells are amongst the most promising energy conversion technologies today. Herein non-precious iron-coordinated nitrogen doped carbons (Fe-N-Cs) as well as metal-free nitrogen-doped carbons (NDCs) are very promising alternatives for Pt-based cathode catalysts. The early reports on the application of such materials date back to the 1960´s when Jasinski demonstrated that - similar to natural porphyrins - N-coordinated transition metal complexes can be active sites for the ORR.1 The preparation of Fe-N-Cs was strongly optimized over the years; still they typically remain with harsh reaction conditions that complicate the selective formation of active FeN4 sites. Until recently, the employment of pyrolytic temperatures was a dogma for the synthesis of FeN4 sites, however coming with unfavorable side reactions. To avoid those harmful side reaction a limit of maximum ≈3 wt.% of Fe (depending on the precursor) was reached, which was also limiting the progress in catalyst performance for this class of materials.2, 3 Since 2006 it was shown that nitrogen doped carbons (NDCs) act as an inexpensive and highly active non-metal catalyst in the oxygen reduction reaction (ORR).4 Both, NDCs and Fe-N-Cs nowadays show the potential to reach performances of practical need, where NDC seem to be promising only for alkaline conditions, while Fe-N-Cs show promise independent of the pH.5, 6 For both PGM-free catalysts, high performance requires advantageous porosity, which typically means high surface area and mass transport pores as well as the control over the chemistry of catalytically active sites. Results and Discussion My group is developing novel synthetic strategies e.g. using molten salts or molten acids as unconventional reaction medium for the preparation of carbons materials.7, 8 Carbon materials with tunable very high surface area of ~2800 m2 g-1 and pore volumes, up to four times as high as in commercial activated carbons, are obtained. Fig. 1: Scheme of the porogenesis mechanism for NDCs by phase separation in of molten salt carbonization (a) to obtain tunable high surface area and porous carbon materials with varying nitrogen content (b). It turned out that such NDCs synthesized in presence of Mg2+ or Zn2+ give rise to a high degree of pyridinic and pyrrolic sites and outstanding ORR activity in alkaline conditions. The salt cations Mg2+ or Zn2+ act as template ions, which results in tetrapyrrolic functional groups embedded into the carbon structure. Based on this, we recently introduced a mild procedure to synthesize Fe-N-C, which leads to active-site formation at low temperatures due to coordination of Fe ions to the tetrapyrrolic functional groups of NDCs.2, 3 Figure 2: Scheme of the Active-Site Imprinting Strategy. A pyrolytic template-ion reaction forms a tetrapyrrolic functional group within the carbon framework (first step). Exchange of the template ion T (with T=Mg2+ or Zn2+) with Fe results in tetrapyrrolic Fe-N-C. The synthesis strategy of active-site imprinting and transmetalation is decoupling the preparation of NDCs from the preparation of the active sites and therefore breaks with the dogma of Fe-N-Cs preparation, circumventing the limitation to 3 wt.% of Fe.9 After a thermal activation step the Fe-N-Cs derived from active site imprinting show very good performance of ORR in acidic conditions, both on the half-cell (rotating disc electrode) and full-cell (5cm2 PEM single cell) level. Figure 3: a) Rotating disk electrode measurements show the large increase in ORR activity and low amount of peroxide formed by exchange of Zn to Fe coordinated to tetrapyrrolic NDC, especially when followed by a second heat treatment. b) Single cell PEMFC H2-O2 tests show a peak power density above 0.4 W cm-2 at a catalyst loading of 2 mg cm-2. Active-site imprinting is currently used by many groups worldwide, successfully pushing the performance of Fe-N-Cs forward, with higher Fe loadings and improved porosities.10-12 Challenges are the moderate turnover frequency (0.24 e- s-1 at 0.8 VRHE) of tetrapyrrolic Fe-N4 sites, 13 and a moderate shelf-life of tetrapyrrolic Fe-N-Cs in atmospheric conditions.14 Besides improvements of electrode engineering and optimization of fuel cell management, an improved synthetic control, leading to more active and stable catalytic environments are needed to tackle the need of sustainable electrocatalysts for future energy conversion technology.15 T2 - International Conference on Materials and Systems for Sustainability (ICMaSS2023) CY - Nagoya, Japan DA - 01.12.2023 KW - PGM-free catalysts PY - 2023 AN - OPUS4-61937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scholl, Juliane T1 - Degradation and Impact of Fluorinated electrolytes from Lithium-Ion Batteries N2 - Lithium-based batteries (LiBs) have become increasingly important in modern society, as cutting-edge portable energy storage systems and as a crucial component in the energy revolution. However, they still face challenges such as safety concerns, capacity degradation, and the ever-growing demand for higher energy density. To address these issues, researchers have turned their attention to fluorinated organic compounds (FOCs) as part of LiBs electrolytes. These substances, closely related to per- and polyfluorinated alkyl substances (PFAS), have shown great potential in optimizing LiBs. Specifically, their strong fluorine-carbon bond offers enhanced oxidative and chemical resistance. Nevertheless, their environmental impact is a cause for concern. Fluorinated organics can persist in the environment or can lead to the formation of persistent end-products, which accumulate and contribute to global health problems. To study the fate of fluorinated organic electrolytes in different environmental and application scenarios, a range of simulation methods are employed, including the TOP (Total Oxidizable Precursor) Assay, electrochemistry, photo-induced degradation, and cycling of self-assembled coin cells prepared with FOCs. Transformation products (TP) are identified using gas chromatography and liquid chromatography coupled with high resolution mass spectrometry (GC/LC-HRMS). T2 - 23. Norddeutsches Doktorandenkolloquium CY - Berlin, Germany DA - 05.10.2023 KW - Transformation products KW - Lithium-ion batteries KW - PFAS KW - TP KW - Batteries KW - Electrolytes PY - 2023 AN - OPUS4-58511 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bruhn, D. A1 - Köhler, S. A1 - Regenspurg, S. A1 - Schumann, F. A1 - Bäßler, Ralph A1 - Dunkelberg, E. A1 - Huenges, E. A1 - Frick, M. A1 - Hirschl, B. A1 - Sass, I. T1 - Positionspapier Wärmeversorgung in Berlin und Brandenburg durch GeoEnergie - Empfehlungen der GeoEnergie Allianz Berlin Brandenburg zu Forschung und Umsetzung N2 - Das gesellschaftliche Ziel der Defossilisierung der Energieversorgung erfordert eine disruptive Veränderung der Wärmebereitstellung. In Berlin und in den größten Brandenburger Städten Potsdam und Cottbus werden noch über 80 % der Nutzwärme über fossile Energieträger bereitgestellt. Die notwendigen Veränderungen erfordern Lösungen, die den tiefen Untergrund der Region nutzen. Allein die Nutzung der tiefen Geothermie kann mindestens 25% des Wärmebedarfs in Deutschland decken. Die Infrastruktur zur Verteilung dieser erneuerbaren Wärme ist bereichsweise vorhanden. Sie muss allerdings lokal und in ländlichen Gebieten weiter ausgebaut werden. Für die Sektoren Strom und Verkehr steht zwar Energie insbesondere aus Sonne und Wind bereit, aber wegen des zeitlich variablen Angebots besteht ein erheblicher Bedarf an großtechnischen Speichern für Strom und Wärme oder auch für Energieträger (z. B. Wasserstoff). Die saisonale oder temporale Überproduktion an Strom und Wärme aus erneuerbaren Energien zwingt dazu, eine urbane Speicherinfrastruktur aufzubauen, um eine grundlastfähige und bedarfsgerechte Lieferung zu realisieren. Hinzu kommt die Aufgabe das Treibhausgas Kohlendioxid aus der Atmosphäre zu reduzieren und unterirdisch dauerhaft zu lagern. Auch hier werden Speichertechnologien und ‐räume benötigt. Die nachhaltige energetische Nutzung des unterirdischen Raumes ist geeignet, entscheidende Beiträge zu einer zukünftigen Energiewirtschaft ohne fossile Brennstoffe zu leisten. Diese große interdisziplinäre Aufgabe erfordert die Zusammenarbeit vieler Fach‐, und Forschungseinrichtungen, die im Raum Berlin‐ Brandenburg vorhanden sind und in einer regionalen Forschungsallianz gebündelt werden sollen. Für die Region Berlin‐Brandenburg ergibt sich daraus die Chance, eine Schlüsselrolle in der Grundlagen‐ und angewandter Forschung zur Transformation des Energiesystems zu übernehmen und weltweit als Vorbild zu dienen. Im vorliegenden Papier werden die Formen einer nachhaltigen Geoenergienutzung, das geologische Potenzial der Region Berlin Brandenburg und dessen bisherige geoenergetische Nutzung dargestellt. Aus diesem Wissen wird der Ist‐Zustand hinsichtlich des energiewirtschaftlichen Potenzials und der sich daraus ergebenden Nutzungsoptionen abgeleitet, um darauf aufbauend Maßnahmen darzustellen, mit denen spürbare Beiträge zur Dekarbonisierung erreicht werden können. Daraus ergeben sich Handlungsempfehlungen für die Region, verbunden mit einem möglichen Beitrag der GEB² zum Risikomanagement, Investitionen in Schlüsseltechnologien, der Aus‐ und Weiterbildung, sowie der Akzeptanzerhöhung für geoenergetische Projekte. T2 - Gründungsveranstaltung der GeoEnergie Allianz Berlin Brandenburg CY - Berlin, Germany DA - 24.11.2023 KW - Geoenergie KW - Geothermie KW - Nachhaltigkeit PY - 2023 SP - 1 EP - 18 CY - Berlin & Potsdam AN - OPUS4-58924 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krug von Nidda, Jonas T1 - Löschwasseruntersuchungen bei Bränden von Energiespeichern mit Lithium-Ionen-Zellen (LöwE) N2 - Die Untersuchung der Zusammensetzung des Löschwassers bei Bränden von Lithium-Ionen-Batterien ist von hohem Interesse. Bisher sind nur wenige bzw. unzureichende Studien in diesem Themenfeld vorhanden. T2 - BAM-UBA-Behördenerfahrungsaustausch 2023 CY - Berlin, Germany DA - 12.06.2023 KW - Lithium-Ionen-Batterien KW - Löschwasser KW - Sicherheit PY - 2023 AN - OPUS4-59273 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krug von Nidda, Jonas T1 - Linking Key Features of Commercial Lithium-Ion Cells to Thermal Runaway Effects and Propagation Behavior N2 - Lithium-ion batteries (LIBs) are essential for the electrification of vehicles and play an important role for stationary storage units needed for grid-balancing. Research groups all over the world work on the improvement of LIBs regarding an increase in energy density as well as cycle-life and a decrease in costs. Next to these research topics, a continuously uprising and crucial field is safety features of LIBs, which can be implemented at different levels, such as material, cell, battery and system level. The abuse/misuse of a LIB can cause an internal release of heat which can trigger a chain of exothermic reactions on cell level. Hence, the cell temperature increases dramatically, causing the so-called thermal runaway (TR), possibly leading to flames and/or explosion of the cell. Moreover, the TR of one cell can initiate the TR of adjacent cells leading to a so-called propagation, possibly, causing the TR of the whole battery. Ideally, easily obtainable key features of a certain cell – such as cathode type, cell format, cell energy and state of charge (SOC) - could allow the prediction of its behaviour under abuse conditions. In the present study, we will discuss the latest result of our safety tests on cell level employing an external heater as TR-trigger. Single cell tests will be analysed regarding different hazardous features during the TR, e.g., cell temperature, occurrence of flames, peak pressure, gas amount and gas composition. Moreover, the possibility of a TR-propagation and the respective propagation speed will be gained from propagation tests utilizing six cells with identical SOC. In total, the study comprises over 200 tests on cell level. The gained data set is analysed in respect to the cell parameters, such as cell format, cell energy, SOC and the cathode type as well as the atmosphere (air vs. N2) present during the test. A special focus is put on the discussion of general conclusions linking cell parameters to TR-effects and propagation behaviour. The findings regarding common conclusions between key features and TR-effects can enable a rather facile selection process of cells/batteries for certain applications according to specific safety targets. Moreover, it allows to choose cell-specific safety measures, suitable during operation. In further works, the study will be extended to end-of-first life cells yielding important conclusions regarding crucial safety aspects for the implementation of those cells in 2nd-life application. Generally, the presented results can increase the overall understanding of the TR mechanism supporting the design of advanced measures to enhance the safety on cell level in the future. T2 - 224th ECS Meeting CY - Gothenburg, Sweden DA - 08.10.2023 KW - Lithium Ion Batteries KW - Thermal Runaway KW - Propagation KW - Safety PY - 2023 AN - OPUS4-59268 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scharpmann, Philippa T1 - In-situ Quantification of the Ageing Dynamics in Lithium-Ion Cells up to Failure-Near Conditions N2 - Implementing end-of-life (EOL) lithium-ion batteries from automotive applications in stationary energy storages is of utmost relevance for a sustainable handling of scarce resources. Beneficial from an economic and ecological perspective, such second-life applications urgently require a guarantee for safe operation. Unlike the state of health (SOH), defined by classical performance indicators such as capacity and voltage, the state of safety (SOS) of an aged battery cannot be assessed straightforward. Its determination requires a plethora of cells to be tested which is a particular challenge for new technologies with limited access to EOL batteries. For providing cells with a defined SOH at a reasonable timescale, we herein propose a novel method of greatly accelerating the ageing process of lithium-ion batteries. In a preliminary test series, lithium-ion NMC pouch cells are exposed to incrementally increasing temperatures, current rates and/or states of charge (SOC), until thermal runaway is induced. In this manner, the critical state in proximity to cell failure is spotted for individual and combined stress parameters. Based on this knowledge, cell-specific test parameters for heavily accelerated ageing are developed. In this protocol, electrical abuse conditions are defined by over/under charging and high current rates. Typically, the cells are cycled utilizing a depth of discharge above 100 %. The accelerated aging dynamics under these critical conditions are monitored by systematic capacity, open circuit voltage and electrochemical impedance spectroscopy (EIS) measurements. This enables a comparative assessment of the electrical behaviour, following conventional vs. heavily accelerated ageing. Such knowledge will in turn help to define the threshold to which cyclic ageing can be accelerated without changing the characteristic degradation mechanisms of lithium-ion batteries. T2 - 244th ECS Meeting CY - Gothenburg, Sweden DA - 08.10.2023 KW - Lithium-Ion Battery KW - Safety KW - Ageing PY - 2023 AN - OPUS4-61490 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krug von Nidda, Jonas T1 - Investigating thermal runaway effects and propagation behaviour of various types of commercial lithium-ion cells N2 - Lithium-ion battery (LIB) powered devices, such as laptops, mobile phones and power tools are ubiquitous in our daily lives. Moreover, LIBs are essential for the electrification of vehicles, and play an important role for stationary storage units needed for grid-balancing. The improvement of LIBs, in terms of increasing energy density as well as cycle-life and decreasing costs, is tackled by numerous research groups all over the world. In the last years, research regarding safety aspects has steadily gained more interest. The safety of LIBs can be implemented at different levels, such as material, cell, battery and system level. The abuse/misuse of an LIB can lead to an internal increase in heat which can trigger a chain of exothermic reactions on cell level. Thus, the cell temperature increases dramatically causing the so-called thermal runaway (TR). This process can lead to flames and/or explosion of the cell. Furthermore, the TR of one cell can initiate the TR of adjacent cells causing the so-called propagation, possibly, leading to the TR of the whole battery. Herein, we will show the latest result of our safety tests on cell level employing an external heater as TR-trigger. Regarding single cell tests, we will compare different hazardous features during the TR, e.g., cell temperature, occurrence of flames, peak pressure, and toxic gases, depending on the cell format, cell energy and the cathode type. The same cell parameters will be used to discuss the results of the propagation tests. Moreover, the influence of the state of charge (SOC) and the present atmosphere (air vs. N2) as well as the repeatability will be discussed. Overall, the study comprises over 180 tests on cell level. The findings regarding the TR behaviour can be used to create a hazard-classification scheme of LIBs, e.g., allowing the definition of (cell type specific) conditions for a safe transport. Furthermore, the results can increase the general understanding of the TR mechanism promoting the development of advanced measures to enhance the safety on cell level in the future. T2 - Advanced Battery Power 2023 CY - Aachen, Germany DA - 27.04.2023 KW - Thermal Runaway KW - Lithium Ion Batteries KW - Safety PY - 2023 AN - OPUS4-59267 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böttcher, Nils T1 - Visualizing the progression of the thermal runaway in lithium-ion-cells by controlled abuse tests at low temperatures N2 - Due to their increasing energy density, lithium-ion-batteries (LIBs) play a key role in the traffic energy transition. Regarding their safety behavior, the main challenge of LIB-cells remains the thermal runaway (TR) process. In situ/operando investigations of the TR on commercial cells is possible with radiographic and computer tomographic measurements. Nonetheless, high resolution visualization of the TR persists as a challenge due to the high progression speed of the TR-process itself. Generally, performing abuse tests at cryogenic temperatures allows to slow down or even prevent the TR. Nevertheless, not all abuse methods are suitable for TR investigations at low temperatures. Nail penetration is an appropriate option, however, contains numerous unknown parameters and therefore suffers regarding reproducibility. Herein, a self-developed high precision nail-penetration-setup is introduced, approaching the necessary mechanically reproducibility with controlled temperatures down to -190°C. The setup allows the preparation of critically abused, however, at cryogenic temperatures stable LIB-cells. These cells were controlled rethermalized to room temperature during synchrotron x-ray computer tomography (SXCT) with a pixel size up to 0.7 μm. During this measurement, the temperature and voltage of the cell is monitored allowing the visualization of the initial internal cell reactions. This study reveals the relation between internal reactions and cell voltage. Finally, the developed set-up enables in-depth analysis of thermal runaway behavior down to material level for various commercial battery cells in the future. T2 - International Battery Safety Workshop CY - Ulm, Germany DA - 28.09.2023 KW - Thermal Runaway KW - Lithium Ion Batteries KW - Computer Tomography PY - 2023 AN - OPUS4-59270 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krug von Nidda, Jonas T1 - Single Cell Exchange in Battery Packs – Sustainability vs. Safety Aspects N2 - Lithium-ion batteries usually consist of numerous individual cells. There is ongoing discussion about enhancing sustainability by considering the replacement of heavily aged or damaged cells. Nevertheless, the planned replacement of individual cells poses significant challenges in ensuring the required reliability and safety of the refurbished device. T2 - KLIB Gesprächsrunde Batteriesysteme CY - Online meeting DA - 16.05.2023 KW - Lithium Ion Batteries KW - Lithium Ion Cells KW - Cell Exchange KW - Safety KW - Sustainability PY - 2023 AN - OPUS4-59272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Appel, Paul Alexander T1 - Developing Tailor-Made Core-Shell Carbon Anode Materials for Sodium Ion Batteries N2 - The current strong interest in electromotive mobility and the need to transition to an energy grid with sustainable energy storage has led to a renewed interest in sodium ion batteries (SIBs). Hard carbons are promising candidates for high-capacity negative electrode materials in SIBs. Their high capacities, however, are often accompanied with high irreversible capacity losses during the initial cycles.[1] The goal of this project is to use analytical techniques to establish a correlation between the structure and the capacities of hard carbons. This has previously been difficult, in part because the sodium storage mechanism is not stoichiometric and due to the disordered structure of hard carbons. Large irreversible capacities associated with hard carbons are often in contradiction to the experimentally determined low surface area of the sample material.[1] A better understanding of the structure-property relationship should enable quantification and understanding of the potential of hard carbon materials for SIBs. Our approach is to explore whether a core-shell structure can separate sodium storage and solid electrolyte interphase formation so that storage capacity and irreversible losses can be investigated separately. The synthesis of a selection of porous carbon structures serving as the core material, will be attempted. Simultaneously, sodium-conducting shell structures will be developed to allow for separation of sodium ions and electrolyte molecules. Subsequently the combination of core and shell materials will be undertaken. These anodes should enable high capacities accompanied with low irreversible capacity due to optimized solid electrolyte interphase formation. T2 - ECS Gothenburg CY - Gothenburg, Sweden DA - 08.10.2023 KW - Energy Materials PY - 2023 AN - OPUS4-62003 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Appel, Paul Alexander T1 - Development of tailormade core-shell hard carbon materials as anode materials in sodium ion batteries N2 - The current strong interest in electromotive mobility and the need to transition to an energy grid with sustainable energy storage has led to a renewed interest in sodium ion batteries (SIBs). Hard carbons are promising candidates for high-capacity negative electrode materials in SIBs. Their high capacities, however, are often accompanied with high irreversible capacity losses, during the initial cycles.[1] The goal of this project is to synthesize carbon materials using different zeolite templates to obtain electrode materials that feature a defined and adjustable pore structure. A better understanding of the structure-property relationship by investigating porosity-tailored anode materials, should enable quantification and understanding of the potential of hard carbon materials for SIBs. Furthermore, a goal is to explore whether a core-shell structure can separate sodium storage and solid electrolyte interphase formation allowing the independent investigation of storage capacity and irreversible losses. T T2 - 34. Deutsche Zeolith-Tagung CY - Vienna, Austria DA - 21.02.2023 KW - Energy Materials PY - 2023 AN - OPUS4-62002 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voss, Heike T1 - Picosecond laser processing of hierarchical micro-nanostructures on Ti-alloy upon pre- and post-anodization N2 - Recent publications indicate that the order of electrochemical anodization (before or after the laser-processing step) plays an important role for the response of boneforming osteoblasts – an effect that can be utilized for improving permanent dental- or removable bone-implants. For exploring these different surface functionalities, multi-method chemical and structural characterizations were performed for two different characteristic micro-spikes covered by nanometric laserinduced periodic surface structures (LIPSS) on Ti-6Al-4V upon irradiation with nearinfrared ps-laser pulses (1030 nm wavelength, ~1 ps pulse duration, 66 & 80 kHz pulse repetition rate) at two distinct sets of laser fluence and beam scanning parameters. This involves morphological and topographical investigations by scanning electron microscopy (SEM) and white light interference microscopy (WLIM), near-surface chemical analysis by X-ray photoelectron spectroscopy (XPS) and hard X-ray photoelectron spectroscopy (HAXPES), as well as structural material examination via X-ray diffraction (XRD) measurements. The results allow to qualify the laser ablation depth, assess the spike geometry and surface roughness parameters, and provide detailed insights into the near-surface oxidation that may cause the different cell growth behavior for pre- or post-anodized medical implants. T2 - E-MRS Spring Meeting 2023 CY - Strasbourg, France DA - 29.05.2023 KW - Hard X-ray photoelectron spectroscopy (HAXPES) KW - Laser-induced periodic surface structures (LIPSS) KW - Ti6Al4V alloy KW - Hierarchical micro-nanostructures KW - Ultrashort laser processing PY - 2023 AN - OPUS4-60344 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Markötter, Henning T1 - Tomographic Imaging Capabilities with hard X-Rays at BAMline (Bessy II) N2 - The BAMline at the synchrotron X-ray source BESSY II (Berlin, Germany) is supporting researchers especially in materials science. As a non-destructive characterization method, synchrotron X-ray imaging, especially tomography with hard X-Rays, plays an important role in structural 3D characterization. The imaging capabilities allow for in-situ and operando experiments. In this presentation the equipment, data handling pipeline as well as various examples from material science are presented. T2 - Correlative Materials Characterization Workshop 2023 CY - Brno, Czech Republic DA - 09.11.2023 KW - Tomography KW - X-ray imaging KW - Li-ion battery PY - 2023 AN - OPUS4-58958 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Okeke, Joseph T1 - In situ and operando imaging, spectroscopy and tomography of batteries N2 - The development of more powerful and more efficient lithium-ion batteries (LIBs) is a key area in battery research, aiming to support the ever-increasing demand for energy storage systems. To better understand the causes and mechanisms of degradation, and thus the diminishing cycling performance and lifetime often observed in LIBs, in operando techniques are essential, because battery chemistry can be monitored non-invasively, in real time. Moreover, there is increasing interest in developing new battery chemistries. Beyond LIBs, sodium ion batteries (NIBs) have gained increasing interest in recent years, as they are a promising candidate to complement LIBs, owing to their improved sustainability and lower cost, while still maintaining high energy density.[1] Initial phases of NIB commercialisation have occurred in the past year. However, for the widespread commercialisation of NIBs, there are still challenges that need to be overcome in developing optimized electrode materials and electrolytes. For the development of such materials and greater understanding of sodium storage mechanisms, solid electrolyte interface (SEI) formation and stability, and degradation processes, in operando methodologies are crucial. Among the techniques available for in operando analysis, nuclear magnetic resonance spectroscopy (NMR) and imaging (MRI) are becoming increasingly used to characterize the chemical composition of battery materials, study the growth and distribution of dendrites, and investigate battery storage and degradation mechanisms. In situ and in operando 1H, 7Li and 23Na NMR and MRI have recently been used to study LIBs and NIBs, identifying chemical changes in Li and Na species respectively, in metallic, quasimetallic and electrolytic environment as well as directly and indirectly studying dendrite formation in both systems.[2-4] The ability of NMR and MRI to probe battery systems across multiple environments can further be complemented by the enhanced spatial resolution of micro-computed X-ray tomography (μ-CT) which can provide insight into battery material microstructure and defect distribution. Here, we report in operando 1H and 7Li NMR and MRI experiments that investigate LIB performance, and the identification of changes in the Li signal during charge cycling, as well as the observation of signals in both 1H and 7Li NMR spectra that we attribute to diminishing battery performance, capacity loss and degradation. Additionally, recent operando methodology are adapted and implemented to study Sn based anodes in NIBs. 23Na spectroscopy is performed to monitor the formation and evolution of peaks assigned to stages of Na insertion into Sn, while 1H MRI is used to indirectly visualize the volume expansion of Sn anodes during charge cycling. Battery operation and degradation is further explored in these NIBs, using μ-CT, where the anode is directly visualized to a higher resolution and the loss of electrolyte in the cell, during cycling is observed T2 - 17th International Conference on Magnetic Resonance Microscopy CY - Singapore DA - 27.08.2023 KW - Sodium ion battery KW - Lithium ion battery KW - NMR KW - MRI KW - Tomography PY - 2023 AN - OPUS4-58421 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Kai A1 - Mirabella, Francesca A1 - Knigge, Xenia A1 - Mezera, Marek A1 - Weise, Matthias A1 - Sahre, Mario A1 - Wasmuth, Karsten A1 - Voss, Heike A1 - Hertwig, Andreas A1 - Krüger, Jörg A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan A1 - Bonse, Jörn T1 - Chemical and topographical changes upon sub-100-nm laser-induced periodic surface structure formation on titanium alloy: the influence of laser pulse repetition rate and number of over-scans N2 - Titanium and its alloys are known to allow the straightforward laser-based manufacturing of ordered surface nanostructures, so-called high spatial frequency laser-induced periodic surface structures (HSFL). These structures exhibit sub-100 nm spatial periods – far below the optical diffraction limit. The resulting surface functionalities are usually enabled by both, topographic and chemical alterations of the nanostructured surfaces. For exploring these effects, multi-method characterizations were performed here for HSFL processed on Ti–6Al–4V alloy upon irradiation with near-infrared ps-laser pulses (1030 nm, ≈1 ps pulse duration, 1–400 kHz) under different laser scan processing conditions, i.e., by systematically varying the pulse repetition frequency and the number of laser irradiation passes. The sample characterization involved morphological and topographical investigations by scanning electron microscopy (SEM), atomic force microscopy (AFM), tactile stylus profilometry, as well as near-surface chemical analyses hard X-ray photoelectron spectroscopy (HAXPES) and depth-profiling time-of-flight secondary ion mass spectrometry (ToF-SIMS). This provides a quantification of the laser ablation depth, the geometrical HSFL characteristics and enables new insights into the depth extent and the nature of the non-ablative laser-induced near-surface oxidation accompanying these nanostructures. This allows to answer the questions how the processing of HSFL can be industrially scaled up, and whether the latter is limited by heat-accumulation effects. T2 - 2023 E-MRS Spring Meeting, Symposium L "Making light matter: lasers in material sciences and photonics" CY - Strasbourg, France DA - 29.05.2023 KW - Laser-induced periodic surface structures (LIPSS) KW - Ultrashort laser pulses KW - Laser processing KW - Hard X-ray photoelectron spectroscopy (HAXPES) KW - Time-of-flight secondary ion mass spectrometry (ToF-SIMS) PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589902 UR - https://onlinelibrary.wiley.com/doi/full/10.1002/pssa.202300719 DO - https://doi.org/10.1002/pssa.202300719 SN - 1862-6319 VL - 221 IS - 15 SP - 1 EP - 12 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-58990 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zaghdoudi, Maha A1 - Kömmling, Anja A1 - Jaunich, Matthias A1 - Wolff, Dietmar A1 - Albouy, P.-A. A1 - Häcker, Ralf A1 - Stock, Daniel T1 - Overview of ongoing research and future prospects on polyethylene neutron shielding materials at bam N2 - The extension of the interim storage period of radioactive waste before disposal will cause additional challenges for the nuclear waste management in Germany, so that an extensive knowledge of the long-term performance of casks, including their components and inventories, will be required for future extended storage licenses. Ultra-high and high molecular weight polyethylenes ((U)HMW-PE) are used for neutron shielding purposes in casks for storage and transport of spent fuel and high-level waste due to their extremely high hydrogen content. During their service life of several decades as cask components, the PE materials are exposed to neutron and gamma radiation from the radioactive inventory of the casks, mechanical assembling stresses and temperature. All these combined effects affect the material properties of such components which in turn may be crucial for some possible accident scenarios. At the Bundesanstalt für Materialforschung und -prüfung (BAM), the effects of high temperature exposure in combination with subsequent or previous irradiation were investigated with a comprehensive aging program including thermal aging at 125 °C for different aging periods up to 5 years and irradiation with doses ranging from 50 to 600 kGy. This contribution provides an overview of the ongoing research related to the structural changes of (U)HMW-PE induced by gamma irradiation and high temperature exposure and focuses on current research perspectives at BAM with regard to the prediction of the dynamic behavior of the material during extended interim storage in case of an accident scenario. First results of the coupled effect of temperature, radiation and mechanical loading will be presented. The effect of microstructural changes induced by gamma irradiation and high temperature on the mechanical behavior of (U)HMW-PE will be assessed. T2 - PATRAM22 CY - Juan-Les-Pins, Antibes, France DA - 11.06.2023 KW - (U)HMWPE KW - Ageing KW - Irradiation KW - WAXD KW - SHPB PY - 2023 SP - 1 EP - 10 AN - OPUS4-57707 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zaghdoudi, Maha T1 - Overview of ongoing research and future prospects on polyethylene neutron shielding materials at BAM N2 - The extension of the interim storage period of radioactive waste before disposal will cause additional challenges for the nuclear waste management in Germany, so that an extensive knowledge of the long-term performance of casks, including their components and inventories, will be required for future extended storage licenses. Ultra-high and high molecular weight polyethylenes ((U)HMW-PE) are used for neutron shielding purposes in casks for storage and transport of spent fuel and high-level waste due to their extremely high hydrogen content. During their service life of several decades as cask components, the PE materials are exposed to neutron and gamma radiation from the radioactive inventory of the casks, mechanical assembling stresses and temperature. All these combined effects affect the material properties of such components which in turn may be crucial for some possible accident scenarios. At the Bundesanstalt für Materialforschung und -prüfung (BAM), the effects of high temperature exposure in combination with subsequent or previous irradiation were investigated with a comprehensive aging program including thermal aging at 125 °C for different aging periods up to 5 years and irradiation with doses ranging from 50 to 600 kGy. This contribution provides an overview of the ongoing research related to the structural changes of (U)HMW-PE induced by gamma irradiation and high temperature exposure and focuses on current research perspectives at BAM with regard to the prediction of the dynamic behavior of the material during extended interim storage in case of an accident scenario. First results of the coupled effect of temperature, radiation and mechanical loading will be presented. The effect of microstructural changes induced by gamma irradiation and high temperature on the mechanical behavior of (U)HMW-PE will be assessed. T2 - PATRAM22 CY - Juan-les-Pins, France DA - 11.06.2023 KW - (U)HMWPE KW - Ageing KW - Irradiation KW - WAXD KW - SHPB PY - 2023 AN - OPUS4-57708 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -