TY - CONF A1 - Tschirschwitz, Rico T1 - Abschlusstreffen BMBF-Vorhaben SEE-2L, Teilvorhaben BAM: Aufbau eines Großversuchsstandes N2 - Der Vortrag stellt den aktuellen Bearbeitungsstand des Teilvorhabens an der BAM dar. Der Schwerpunkt liegt dabei auf der ersten Versuchsserie mit Batteriezellen und -modulen bis zu 6.8 kWh. Darüber hinaus werden die weiteren geplanten Versuche vorgestellt sowie die Ergbnisverwertung aus dem Projekt aufgezeigt. T2 - Abschlusstreffen zum BMBF-Vorhaben SEE-2L CY - Online meeting DA - 24.04.2023 KW - Stationäre Energiespeicher KW - Elektrische Energiespeicher KW - Auswirkungsbetrachtungen KW - Lithium-Ionen-Batterie PY - 2023 AN - OPUS4-57582 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tschirschwitz, Rico T1 - A study on thermal runaway propagation in battery cells and modules assembled of pouch cells N2 - Every technical system has a failure rate, including a lithium-ion battery. To minimize the effects in the event of a thermal runaway, it is necessary to know what consequences to expect. In the talk, current results from tests on the thermal runaway behaviour of lithium-ion batteries will be presented and conclusions drawn for the handling of those. T2 - EUSAS Conference 2023, "Addressing the fire risks of electromobility" CY - Frankfurt am Main, Germany DA - 10.05.2023 KW - Electrical Energy Storage KW - Lithium-ion battery KW - Propagation KW - Consequneces PY - 2023 AN - OPUS4-57583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Bernardy, Christopher A1 - Wagner, Patrick A1 - Rappsilber, Tim A1 - Liebner, Christian A1 - Hahn, S.-K. A1 - Krause, U. T1 - Harmful effects of lithium-ion battery thermal runaway: scale-up tests from cell to second-life modules N2 - For a comprehensive safety assessment of stationary lithium-ion-battery applications, it is necessary to better understand the consequences of thermal runaway (TR). In this study, experimental tests comprising twelve TR experiments including four single-cell tests, two cell stack tests and six second-life module tests (2.65 kW h and 6.85 kW h) with an NMC-cathode under similar initial conditions were conducted. The temperature (direct at cells/modules and in near field), mass loss, cell/module voltage, and qualitative vent gas composition (Fourier transform infrared (FTIR) and diode laser spectroscopy (DLS) for HF) were measured. The results of the tests showed that the battery TR is accompanied by severe and in some cases violent chemical reactions. In most cases, TR was not accompanied by pregassing of the modules. Jet flames up to a length of 5 m and fragment throwing to distances to more than 30 m were detected. The TR of the tested modules was accompanied by significant mass loss of up to 82%. The maximum HF concentration measured was 76 ppm, whereby the measured HF concentrations in the module tests were not necessarily higher than that in the cell stack tests. Subsequently, an explosion of the released vent gas occurred in one of the tests, resulting in the intensification of the negative consequences. According to the evaluation of the gas measurements with regard to toxicity base on the “Acute Exposure Guideline Levels” (AEGL), there is some concern with regards to CO, which may be equally as important to consider as the release of HF. KW - Large-scale tests KW - Lithium-ion battery KW - Gas emission KW - Thermal runaway KW - Consequences PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579054 DO - https://doi.org/10.1039/D3RA02881J SN - 2046-2069 VL - 13 IS - 30 SP - 20761 EP - 20779 PB - Royal Society of Chemistry (RSC) CY - Cambridge, UK AN - OPUS4-57905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Amano, K. O. A. A1 - Hahn, S.-K. A1 - Butt, N. A1 - Vorwerk, P. A1 - Gimadieva, E. A1 - Tschirschwitz, Rico A1 - Rappsilber, Tim A1 - Krause, U. T1 - Composition and Explosibility of Gas Emissions from Lithium-Ion Batteries Undergoing Thermal Runaway N2 - Lithium-based batteries have the potential to undergo thermal runaway (TR), during which mixtures of gases are released. The purpose of this study was to assess the explosibility of the gaseous emission from LIBs of an NMC-based cathode during thermal runaway. In the current project, a series of pouch lithium-based battery cells was exposed to abuse conditions (thermal) to study the total amount of gases released and the composition of the gas mixture. First, the battery cells were placed in a closed vessel, and the pressure and temperature rise inside the vessel were measured. In a second step, the composition of gases was analysed using a Fourier transform Infrared (FTIR) spectrometer. We found that the amount of released gases was up to 102 ± 4 L, with a clear dependence on the battery capacity. This study showed that the concentration of gaseous emissions such as carbon monoxide (CO), methane (CH4), ethylene (C2H4), ethane (C2H6), and hydrogen cyanide (HCN) increased with higher cell capacity. Of the five studied flammable gases, the maximum concentrations of carbon monoxide (16.85 vol%), methane (7.6 vol%), and ethylene (7.86 vol%) were identified to be within their explosible range. Applying Le Chatelier’s law, a calculated lower explosion limit (LEL) of 7% in volume fraction was obtained for the gas mixture. The upper explosion limit (UEL) of the gas mixture was also found to be 31% in volume. A filter comprising pyrobubbles was used for the removal of the studied gas components released during the thermal abuse. The investigation revealed that the pyrobubbles filter was highly effect in the removal of HCN (up to 94% removal) and CO2 (up to 100% removal). Herein, we report the dependency of the method of thermal runaway trigger on the measured maximum temperature. KW - Lithium-ion battery KW - Thermal runaway KW - Smoke gas emission KW - Gas explosion KW - Explosion limit PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576477 DO - https://doi.org/10.3390/batteries9060300 VL - 9 IS - 6 SP - 1 EP - 19 PB - MDPI CY - Basel, Switzerland AN - OPUS4-57647 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Albakri, Bashar T1 - Robustness in Fatigue Strength Estimation N2 - Researchers study the properties of polymeric membranes - an important building block of batteries – by first measuring its impedance spectra and then determining a so called equivalent electronic circuit (EEC), that is an electronic circuit that approximately reproduces these measurements. Determining EEC is not completely automatized since it includes the search for the topology of the electronic circuit. This search is an inverse problem, since the formulas for determining the impedance spectra given the circuit topology and parameters are known while there are no formulas for the invers direction. To solve this invers problem, the original problem is split into two parts. The first part is to determine the topology of the circuit and the second part is to determine the parameters of the circuit. For the first part a Convolutional Neural Network Classifier is trained on a simulated data set, where the simulator is an implementation of the formulas for determining the impedance spectra given the complete description of the electronic circuit. After the topology is determined, the parameters of the electronic circuit are found by minimizing the error between the observed spectra and the spectra corresponding to these parameters. This minimization is a global optimization. T2 - Mathematical and Statistical Methods for Metrology; MSMM 2023 CY - Turin, Italy DA - 30.05.2023 KW - Equivalent Electrical Circuits KW - Electrochemical Impedance Spectroscopy KW - Neural Networks KW - Global Optimization PY - 2023 AN - OPUS4-57677 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sablowski, J. A1 - Lugovtsova, Yevgeniya A1 - Bulling, Jannis A1 - Kupsch, C. T1 - Experimental Study of Ultrasonic Guided Waves in a Bipolar Plate of a Fuel Cell N2 - Water management in proton-exchange membrane fuel cells (PEMFCs) is critical for efficient operation. However, in-situ measurements of the water distribution in an operating PEMFC are challenging. In this study, we investigate key aspects of ultrasonic guided wave (UGW) propagation through the bipolar plate of a PEMFC using 3D scanning laser Doppler vibrometry (3D LDV). Our results provide insights for the design and optimization of UGW-based sensor systems for water detection in PEMFCs. T2 - 2023 IEEE International Ultrasonics Symposium (IUS) CY - Montreal, QC, Canada DA - 03.09.2023 KW - Ultrasonic guided waves KW - Laser Doppler vibrometry KW - Fuel cells KW - Water management PY - 2023 DO - https://doi.org/10.1109/IUS51837.2023.10307327 SP - 1 EP - 4 PB - IEEE AN - OPUS4-59540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - el Dsoki, Chalid T1 - Anforderungen für den Transport kritisch-defekter Lithiumbatterien nach Sondervorschrift 376 N2 - Die BAM legt als zuständige Behörde die zusätzlichen Prüfanforderungen an die verwendeten Verpackungen/ Großverpackungen nach P 911 und LP 906 fest (Teil A dieser BAM-GGR). Außerdem kann die BAM gemäß Sondervorschrift 376 davon abweichende alternative Verpackungs- und/oder Beförderungsbedingungen zulassen (Einzelfallfestlegung,Teil B dieser BAM-GGR). T2 - 19. Gefahrgut Technik Tage CY - Berlin, Germany DA - 16.11.2023 KW - Gefahrgutregel Transport kritische Batterien PY - 2023 AN - OPUS4-59067 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - el Dsoki, Chalid T1 - Hitzebeständigkeit von Funkgeräten N2 - Lithium-Akkus können bei großer Hitzeeinwirkung thermisch durchgehen. Und doch sind sie in vielen Geräten der Feuerwehr verbaut, zum Beispiel in Funkgeräten. Ein Sicherheitsrisiko beim Löscheinsatz? KW - Funkgeräte Löscheinsatz PY - 2023 IS - 12 SP - 64 EP - 66 AN - OPUS4-59075 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tschirschwitz, Rico T1 - BEV Accidents - Consequences in Case of a Battery Thermal Runaway N2 - The number of cars which use a battery for propulsion, like BEV (battery electric vehicle) or PHEV (plug-in hybrid electric vehicle), is increasing. Following, the probability of these car types being involved in car accidents will increase. In a worst-case accident scenario, the installed batteries could go under thermal runaway (TR). A TR could be initiated by various causes, e.g., high temperatures from outside, mechanical damage of the cells/modules/batteries or internal and external short circuits. During such an event, large amounts of heat and toxic and/or flammable gases are released. This poses a great hazard to people and property in the immediate vicinity. The paper describes a large-scale test series on the lithium-ion battery TR consequences of automobile cells and modules up to E = 6.85 kWh. Near field temperatures of ΔT > 800°C in a distance of l = 2 m were measured. During an overcharge test, fragment throwing distances of l > 30 m were detected. Subsequent gas explosions of the released gases were documented. Hydrogen fluoride (HF) was measured in all tests, from cell to module. The highest measured concentration was cHF = 76 ppm, which is significantly higher than the 30-min-level for AEGL 2 (acute exposure guideline level 2). Based on the experimentally determined consequences, concrete measures for the accident analysis are subsequently drawn. T2 - 31st Annual Congress of the European Association for Accident Research and Analysis (EVU) CY - Limassol, Cyprus DA - 05.10.2023 KW - Consequences KW - Electrical Energy Storage KW - Lithium-ion battery KW - BEV KW - Gas release PY - 2023 AN - OPUS4-58547 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tschirschwitz, Rico A1 - Hahn, Sarah-K. A1 - Krause, Ulrich T1 - BEV Accidents - Consequences in Case of a Battery Thermal Runaway N2 - The number of cars which use a battery for propulsion, like BEV (battery electric vehicle) or PHEV (plug-in hybrid electric vehicle), is increasing. Following, the probability of these car types being involved in car accidents will increase. In a worst-case accident scenario, the installed batteries could go under thermal runaway (TR). A TR could be initiated by various causes, e.g., high temperatures from outside, mechanical damage of the cells/modules/batteries or internal and external short circuits. During such an event, large amounts of heat and toxic and/or flammable gases are released. This poses a great hazard to people and property in the immediate vicinity. The paper describes a large-scale test series on the lithium-ion battery TR consequences of automobile cells and modules up to E = 6.85 kWh. Near field temperatures of ΔT > 800°C in a distance of l = 2 m were measured. During an overcharge test, fragment throwing distances of l > 30 m were detected. Subsequent gas explosions of the released gases were documented. Hydrogen fluoride (HF) was measured in all tests, from cell to module. The highestmeasured concentration was cHF = 76 ppm, which is significantly higher than the 30-min-level for AEGL 2 (acute exposure guideline level 2). Based on the experimentally determined consequences, concrete measures for the accident analysis are subsequently drawn. T2 - 31st Annual Congress of the European Association for Accident Research and Analysis (EVU) CY - Limassol, Cyprus DA - 05.10.2023 KW - Gas release KW - Consequences KW - Lithium-ion battery KW - Electrical Energy Storage KW - BEV PY - 2023 SP - 1 EP - 18 AN - OPUS4-58552 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Hahn, Sarah-K. A1 - Saupe, Alexander A1 - Janßen, Marvin A1 - Krause, Ulrich T1 - Sicherheitsrisiko Batterien – Demonstrator aus dem Projekt SEE-2L bereits im Einsatz N2 - Der Beitrag beschreibt das BMBF-Verbundvorhaben SEE-2L. Im Artikel werden die wesentlichen Meilensteine des Projektes vorgestellt. Ebenso werden die wichtigsten im Projekt erzielten Ergebnisse aufgeführt und verlinkt. KW - Stationäre Energiespeicher KW - Batterie KW - Auswirkungsbetrachtungen KW - EES KW - Elektrische Energiespeicher PY - 2023 UR - https://info.sifo.de/public/a_25436_GZ5jd/file/data/669_Informationsbrief_zur_zivilen_Sicherheitsforschung_07-2023.pdf#page=7 IS - 7 SP - 7 EP - 9 PB - Bundesministerium für Bildung und Forschung (BMBF) CY - Bonn AN - OPUS4-58347 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Amano, Kofi Owusu Ansah T1 - Study of thermal runaway and gas emissions in NMC lithium-ion batteries: State of Charge Dependence Investigation N2 - Thermal runaway investigations were performed by subjecting single and double NMC pouch cells to thermal abuse condition inside an air-tight reactor vessel with an internal volume of 100 dm³. The study was divided into two series. The findings revealed the thermal runaway-induced explosion in the cells results in a rate of temperature increase greater than 10 K/s. The highest gaseous production was achieved at a range of 90 – 100% SOC and higher battery capacities 0.79 L/Wh (Series 1, 10 Ah cell) and 0.87 L/Wh (Series 2, 32 Ah cell). The investigation showed between 25 m³ and 84 m³ of explosible gas mixture could be released from electric vehicles of nominal useable electrical energy from 32 kWh up to 108 kWh at thermal runaway. It was also found that, the release of these explosible gases could undergo a secondary explosion. T2 - 4th IBSW 2023 – International Battery Safety Workshop CY - Ulm, Germany DA - 28.09.2023 KW - Consequneces KW - Electrical Energy Storage KW - Propagation; Gas release KW - Lithium-ion battery PY - 2023 AN - OPUS4-58543 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Hahn, Sarah-K. A1 - Krause, Ulrich T1 - BMBF-Vorhaben SEE-2L - Auswirkungen des thermischen Durchgehens von Second-Life-Lithium-Ionen-Batterien auf Modulebene N2 - Elektrische Energiespeicher können unter bestimmten Bedingungen thermisch Durchgehen. Dies ist mit der Freisetzung von großen Mengen an Wärme sowie toxischen und/oder brennbaren Gasen assoziiert. Um die potenziellen Auswirkungen des thermischen Durchgehens zu quantifizieren, wurden Versuche mit Zellen und Modulen mit einem Energieinhalt von bis zu E = 6,85 kWh durchgeführt. Es wurden verschiedene Kenngrößen, wie z.B. Temperatur, Spannung, Massenabbrand, qualitative Gaszusammensetzung sowie Fragmente, messtechnisch erfasst und ausgewertet. Die Ergebnisse können sowohl für Bemessungen im vorbeugenden baulichen Brandschutz als auch in der Prozess- und Anlagensicherheit verwendet werden. Ebenso können sie in Konzept des abwehrenden Brandschutzes integriert werden. KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Lithium-Ionen-Batterie KW - Stationäre Energiespeicher KW - Thermisches Durchgehen PY - 2024 SN - 1868-6540 VL - 73. Jahrgang IS - 3 SP - 111 EP - 122 PB - Ebner Media Group GmbH & Co. KG CY - Ulm AN - OPUS4-61082 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hahn, S.-K. A1 - Tschirschwitz, Rico A1 - Bernardy, Christopher T1 - Forschung zur Sicherheit stationärer Energiespeicher - Zwischenspeicher als wichtiger Beitrag für eine erfolgreiche Energiewende N2 - Der Artikel stellt das BMBF-Vorhaben SEE-2L dar. Der Schwerpunkt liegt dabei auf dem Beitrag des Vorhabens für die Sicherheit von stationären Energiespeichern. Darüber hinaus wird aufgezeigt, welche Versuche bisher durchgeführt wurden und mit welchen Ergebnissen bis Projektende zu rechnen ist. KW - Stationäre Energiespeicher KW - Elektrische Energiespeicher KW - Auswirkungsbetrachtungen KW - Batterie KW - Thermal runaways PY - 2022 UR - https://www.behoerden-spiegel.de/e-mobility-magazin-2022/ SN - 1437-8337 VL - 2022 IS - Sonderheft E-Mobility Magazin 2022 SP - 23 EP - 24 PB - ProPress CY - Bonn AN - OPUS4-56401 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tschirschwitz, Rico T1 - Projekttreffen BMBF-Vorhaben SEE-2L, Teilvorhaben BAM: Aufbau eines Großversuchsstandes N2 - Der Vortrag stellt den aktuellen Bearbeitungsstand des Teilvorhabens an der BAM dar. Der Schwerpunkt liegt dabei auf der ersten Versuchsserie mit Batteriezellen und -modulen bis zu 6.8 kWh. Aus diesen Versuche werden die wesentlichen Ergebnisse gezeigt, insbesondere die Teperatur-, Spannungs, Gas- und Gewichtsmessung beim thermischen Durchgehen. T2 - Projekttreffen zum BMBF-Vorhaben SEE-2L (Sicherheit elektrochemischer Energiespeicher in Second Life Anwendungen) CY - BAM TTS, Baruth/Mark - Horstwalde, Germany DA - 08.11.2022 KW - Stationäre Energiespeicher KW - Elektrische Energiespeicher KW - Auswirkungsbetrachtungen KW - EES PY - 2022 AN - OPUS4-56212 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Sarah-K. A1 - Tschirschwitz, Rico A1 - Amano, Kofi Owusu Ansah A1 - Gimadieva, Elena A1 - Krause, Ulrich T1 - A Study on Thermal Runaway Propagation in Battery Modules Assembled from Pouch Cells N2 - Thermal runaway reactions were studied in arrangements from single battery cells with energy capacities of 2.5 Ah (9.25 Wh) to battery modules up to 6.85 kWh. All cells were pouch cells of the Li-ion NMC type and the modules were composed of such. Abuse was triggered either by overcharging or thermally by attaching a heat source (heating plate or glow plug) to the cells. Experiments with single cells or assemblies of two to four cells were undertaken in closed autoclaves. Samples of the gas released from the cells during the runaway were extracted and analysed using a Fourier-transformed infrared spectrometer (FTIR). In some experiments pressure peaks up to 7 bar (g) were observed which could not be explained by the gas release alone. Obviously, secondary explosions took place. Thermal runaway propagation was studied with and without an insulation layer between the battery cells. Several materials and combinations of them were tested as insulations: hollow glass spheres (Pyrobubbles®), phase change materials (PCM) and intumescent materials. Experiments showed that already layers of 10 to 20 mm of insulation effectively prevented the propagation of a thermal runaway. In addition to the experiments, a mathematical model was developed for studying numerically the heat transfer through arrangements of multiple battery cells and also the effect of insulation layers. This model was implemented into the commercial finite-element software package COMSOL Multiphysics®. The simulations confirmed the experimental findings that already quite thin insulation layers between cells or modules effectively delay or even suppress the propagation of the thermal runaway. T2 - EUSAS conference "Addressing the Fire Risks of Electromobility" CY - Frankfurt am Main, Germany DA - 10.05.2023 KW - Thermal Runaway KW - Consequences KW - Electrical Energy Storage KW - Gas release KW - Lithium-ion battery PY - 2024 UR - https://eusas.eu/publications/eusas-journals VL - 15 SP - 43 EP - 50 PB - EUSAS e.V. (European Society for Automatic Alarm Systems e.V.), Universität Duisburg-Essen, Dept. Nachrichtentechnische Systeme CY - Duisburg AN - OPUS4-61598 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Sarah-K. T1 - Second Life Verwendungen - Untersuchungen und erste Erfahrungen mit einem Ausbildungsdemonstrator N2 - Der Vortrag gibt zunächst einen Themeneinstieg in den Bereich der Second-Life-Batterien sowie rechtliche und technische Grundlagen zu Lebenszyklus und Alterung. Im Weiteren werden experimentelle Ergebnisse aus Versuchen zum thermischen Durchgehen mit Batteriemodulen aus dem BMBF-Vorhaben SEE-2L vorgestellt. Darüber hinaus wird ein eigens entwickelter Ausbildungsdemonstrators vorgestellt, welcher einen wesentlichen Baustein des Ergebnistransfers aus dem Vorhaben darstellt. T2 - Brände von Lithium-Ionen Batterien in Elektrofahrzeugen kontrollieren, eindämmen und vorbeugen CY - Essen, Germany DA - 25.04.2024 KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Lithium-Ionen-Batterie KW - Stationäre Energiespeicher KW - Thermisches Durchgehen PY - 2024 AN - OPUS4-60187 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tschirschwitz, Rico T1 - Sicherheit stationärer elektrischer Energiespeicher – Ergebnisse aus dem Projekt SEE-2L N2 - Einleitend wird im Vortrag das Aktivitätsfeld Elektrische Energiespeicher und -umwandlung vorgestellt sowie eine kurze Einführung in die Terminologie der elektrischen Energiespeicher gegeben. Im Folgenden wird das BMBF-Vorhaben SEE-2L vorgestellt. Hier wird der Schwerpunkt auf die Entwicklung und den Aufbau eines Großversuchsstand für das thermische Durchgehen von Lithium-Batterien auf Modul- und Batterieebene gelegt. Darüber hinaus werden die Ergebnisse einer ersten Versuchsserie vorgestellt. Zum Abschluss wird ein kurzer Ausblick zu weiteren anstehenden Versuchen gegeben. T2 - Behörden-Erfahrungsaustausch Anlagensicherheit 2024 CY - Berlin, Deutschland DA - 03.06.2024 KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Lithium-Ionen-Batterie KW - Stationäre Energiespeicher KW - Thermisches Durchgehen PY - 2024 AN - OPUS4-60190 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Sarah-K. T1 - Sicherheit elektrochemischer Energiespeicher – Ergebnisse aus dem Projekt SEE-2L N2 - Die Transformation der Energienutzung von konventionellen zu erneuerbaren Quellen führt dazu, dass zukünftig mehr Energie effizient zwischengespeichert werden muss. Eine Möglichkeit der elektrochemischen Zwischenspeicherung bieten Lithium-Ionen-Batterien. Hierfür können ausgemusterte Automobilantriebsbatterien verwendet werden. Erfüllen sie die hohen Anforderungen des mobilen Bereichs nicht mehr, haben sie oftmals noch eine ausreichende Kapazität und Leistungsfähigkeit für die stationäre Zwischenspeicherung. Neben der Verwendung der Batterien im größeren Maßstab, z.B. bei Energieversorgern, werden durch den vermehrten Einsatz von Photovoltaik-Anlagen in Ein- und Mehrfamilienhäusern verstärkt Zwischenspeicher für Privathaushalte nachgefragt. Dies birgt auch für Einsatzkräfte neue Herausforderungen in der Gefahrenabwehr. Im vom Bundesministerium für Bildung und Forschung (BMBF) geförderten Verbundprojekt „SEE-2L – Sicherheit elektrochemischer Energiespeicher in Second Life Anwendungen“ wurden Versuche mit Second Life Modulen durchgeführt. Verbundpartner im Projekt waren neben der vfdb die Otto-von-Guericke-Universität Magdeburg und die Bundesanstalt für Materialforschung und -prüfung. Zudem war das Institut der Feuerwehr Nordrhein-Westfalen eingebunden. Die durchgeführten Versuche bilden eine Grundlage für die Einordnung der Batteriespeicher, z.B. aus Sicht des baulichen Brandschutzes, zur Methodik der Brandbekämpfung oder zur Risikobewertung hinsichtlich der Prozess- und Anlagensicherheit. Im Beitrag werden die Versuchsergebnisse vorgestellt und Ansätze für deren Anwendung gezeigt. Um die gewonnenen Erkenntnisse zu vermitteln, wurde im Projekt zudem ein Schulungskonzept für Einsätze mit Lithium-Ionen-Technologien erarbeitet, das im Beitrag präsentiert wird. Es besteht aus theoretischen und praktischen Anteilen, sodass bei den Feuerwehren praxisnah aus- bzw. fortgebildet werden kann. T2 - vfdb-Jahresfachtagung CY - Magdeburg, Ger DA - 06.05.2024 KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Lithium-Ionen-Batterie KW - Stationäre Energiespeicher KW - Thermisches Durchgehen PY - 2024 AN - OPUS4-60192 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Tschirschwitz, Rico A1 - Bernardy, Christopher T1 - Aufbau eines Großversuchsstandes sowie Realisierung von Brandversuchen mit elektrischen Energiespeichern im Bereich bis 500 kWh - Schlussbericht zum Teilvorhaben BAM, Teil I: Kurzbericht N2 - Der Abschlussbericht stellt die wesentlichen Arbeitsschritte und Ergebnisse des Teilvorhabens der BAM im BMBF-Vorhaben SEE-2L vor. Im Rahmen dieses Vorhabens wurde auf dem Testgelände Technische Sicherheit (BAM TTS) ein Großversuchsstand für das thermische Durchgehen von Lithium-Batterien auf Modul- und Batterieebene entwickelt und aufgebaut. Im Zuge des Projektes konnte eine erste Versuchsserie zu den Auswirkungen des thermischen Durchgehens von Batteriemodulen durchgeführt werden. Der Abschlussbericht umfasst zwei Teile, im Teil I den Kurzbricht und im Teil II die eingehende Darstellung. KW - Thermisches Durchgehen KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Stationäre Energiespeicher KW - Lithium-Ionen-Batterie PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600676 DO - https://doi.org/10.2314/KXP:1887873864 N1 - Das Projekt SEE-2L ist ein drittmittelfinanziertes Verbundvorhaben des BMBF, Förderkennzeichen 13N15493, Projektlaufzeit 01.02.2021 - 30.04.2023. SP - 1 EP - 20 PB - Technische Informationsbibliothek (TIB) CY - Hannover AN - OPUS4-60067 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Sarah-K. A1 - Saupe, Alexander A1 - Tschirschwitz, Rico A1 - Bernardy, Christopher A1 - Janßen, Marvin A1 - Amano, Kofi Owusu Ansah A1 - Krause, Ulrich T1 - Sicherheit elektrochemischer Energiespeicher – Ergebnisse aus dem Projekt SEE-2L N2 - Die Transformation der Energienutzung von konventionellen zu erneuerbaren Quellen führt dazu, dass zukünftig mehr Energie effizient zwischengespeichert werden muss. Eine Möglichkeit der elektrochemischen Zwischenspeicherung bieten Lithium-Ionen-Batterien. Hierfür können ausgemusterte Automobilantriebsbatterien verwendet werden. Erfüllen sie die hohen Anforderungen des mobilen Bereichs nicht mehr, haben sie oftmals noch eine ausreichende Kapazität und Leistungsfähigkeit für die stationäre Zwischenspeicherung. Neben der Verwendung der Batterien im größeren Maßstab, z.B. bei Energieversorgern, werden durch den vermehrten Einsatz von Photovoltaik-Anlagen in Ein- und Mehrfamilienhäusern verstärkt Zwischenspeicher für Privathaushalte nachgefragt. Dies birgt auch für Einsatzkräfte neue Herausforderungen in der Gefahrenabwehr. Im vom Bundesministerium für Bildung und Forschung (BMBF) geförderten Verbundprojekt „SEE-2L – Sicherheit elektrochemischer Energiespeicher in Second Life Anwendungen“ wurden Versuche mit Second Life Modulen durchgeführt. Verbundpartner im Projekt waren neben der vfdb die Otto-von-Guericke-Universität Magdeburg und die Bundesanstalt für Materialforschung und -prüfung. Zudem war das Institut der Feuerwehr Nordrhein-Westfalen eingebunden. Die durchgeführten Versuche bilden eine Grundlage für die Einordnung der Batteriespeicher, z.B. aus Sicht des baulichen Brandschutzes, zur Methodik der Brandbekämpfung oder zur Risikobewertung hinsichtlich der Prozess- und Anlagensicherheit. Im Beitrag werden die Versuchsergebnisse vorgestellt und Ansätze für deren Anwendung gezeigt. Um die gewonnenen Erkenntnisse zu vermitteln, wurde im Projekt zudem ein Schulungskonzept für Einsätze mit Lithium-Ionen-Technologien erarbeitet, das im Beitrag präsentiert wird. Es besteht aus theoretischen und praktischen Anteilen, sodass bei den Feuerwehren praxisnah aus- bzw. fortgebildet werden kann. T2 - 70. Jahresfachtagung der vfdb CY - Magdeburg, Deutschland DA - 06.05.2024 KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Lithium-Ionen-Batterie KW - Stationäre Energiespeicher KW - Thermisches Durchgehen PY - 2024 SN - 978-3-9360-5038-7 SP - 645 EP - 657 PB - vfdb, Vereinigung zur Förderung des Deutschen Brandschutzes e.V. CY - Münster AN - OPUS4-60068 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Albakri, Bashar A1 - Turski Silva Diniz, Analice A1 - Benner, Philipp A1 - Muth, Thilo A1 - Nakajima, Shinichi A1 - Favaro, Marco A1 - Kister, Alexander ED - Hillman, Robert T1 - Machine learning-assisted equivalent circuit identification for dielectric spectroscopy of polymers N2 - Polymers have become indispensable across fields of application, and understanding their structure–property relationships and dynamic behaviour is essential for performance optimization. Polymer membranes, particularly ion exchange membranes, play a crucial role in renewable energy conversion technologies, fuel cells, solar energy conversion, and energy storage. In this context, broadband dielectric spectroscopy (BDS) offers a powerful, non-destructive approach to investigate the electrical response and relaxation dynamics of polymers. These properties are investigated by parametrizing the system’s impedance response in terms of a network of circuit elements, i.e. the electrical equivalent circuit (EEC), whose impedance resembles the one of the system under investigation. However, the determination of the EEC from BDS data is challenging due to system complexity, interdependencies of circuit elements, and researcher biases. In this work, we propose a novel approach that incorporates a convolutional neural network (CNN) model to predict the EEC topology. By reducing user bias and enhancing data analysis, this approach aims to make BDS accessible to both experienced users and those with limited expertise. We show that the combination of machine learning and BDS provides valuable insights into the dynamic behaviour of polymer membranes, thus facilitating the design and characterization of tailored polymers for various applications. We also show that our model outperforms state-of-the-art machine learning methods with a top-5 accuracy of around 80% for predicting the circuit topology and a parameter fitting error as low as 0.05%. KW - Polymer membranes KW - Electrochemical impedance spectroscopy KW - Broadband dielectric spectroscopy KW - Deep learning KW - Machine learning KW - Equivalent circuit PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-602138 DO - https://doi.org/10.1016/j.electacta.2024.144474 SN - 0013-4686 VL - 496 SP - 1 EP - 13 PB - Elsevier Ltd. AN - OPUS4-60213 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tschirschwitz, Rico T1 - Sicherheit elektrochemischer Energiespeicher - Ergebnisse aus dem Projekt SEE-2L N2 - Im Rahmen des BMBF-Vorhabens SEE-2L wurde auf dem Testgelände Technische Sicherheit (BAM TTS) ein Großversuchsstand für das thermische Durchgehen von Lithium-Batterien auf Modul- und Batterieebene entwickelt und aufgebaut. Im Zuge des Projektes konnte eine erste Versuchsserie zu den Auswirkungen des thermischen Durchgehens von Batteriemodulen durchgeführt werden. Im Vortrag werden die wesentlichen Ergebnisse der Versuche vorgestellt. T2 - Magdeburg-Köthener Brandschutz- und Sicherheitstagung CY - Magdeburg, Germany DA - 14.03.2024 KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Lithium-Ionen-Batterie KW - Stationäre Energiespeicher KW - Thermisches Durchgehen PY - 2024 AN - OPUS4-60143 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Li, Guiping A1 - Liu, Ye A1 - Schultz, Thorsten A1 - Exner, Moritz A1 - Muydinov, Ruslan A1 - Wang, Hui A1 - Scheurell, Kerstin A1 - Huang, Jieyang A1 - Szymoniak, Paulina A1 - Pinna, Nicola A1 - Koch, Norbert A1 - Adelhelm, Philipp A1 - Bojdys, Michael J. T1 - One‐Pot Synthesis of High‐Capacity Sulfur Cathodes via In‐Situ Polymerization of a Porous Imine‐Based Polymer N2 - AbstractLithium‐ion batteries, essential for electronics and electric vehicles, predominantly use cathodes made from critical materials like cobalt. Sulfur‐based cathodes, offering a high theoretical capacity of 1675 mAh g−1 and environmental advantages due to sulfur's abundance and lower toxicity, present a more sustainable alternative. However, state‐of‐the‐art sulfur‐based electrodes do not reach the theoretical capacities, mainly because conventional electrode production relies on mixing of components into weakly coordinated slurries. Consequently, sulfur‘s mobility leads to battery degradation—an effect known as the “sulfur‐shuttle”. This study introduces a solution by developing a microporous, covalently‐bonded, imine‐based polymer network grown in situ around sulfur particles on the current collector. The polymer network (i) enables selective transport of electrolyte and Li‐ions through pores of defined size, and (ii) acts as a robust host to retain the active component of the electrode (sulfur species). The resulting cathode has superior rate performance from 0.1 C (1360 mAh g−1) to 3 C (807 mAh g−1). Demonstrating a high‐performance, sustainable sulfur cathode produced via a simple one‐pot process, our research underlines the potential of microporous polymers in addressing sulfur diffusion issues, paving the way for sulfur electrodes as viable alternatives to traditional metal‐based cathodes. KW - In-situ polymerization KW - Sulfur cathodes PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604215 DO - https://doi.org/10.1002/anie.202400382 SN - 1433-7851 SP - 1 EP - 11 PB - Wiley VHC-Verlag AN - OPUS4-60421 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Amano, Kofi Owusu Ansah T1 - Thermal runaway characteristics and gas emission from sodium-ion cells – impact of state of charge level N2 - Like lithium batteries, sodium batteries can also undergo thermal runaway. In a series of tests, 30 thermal runaway tests were carried out with sodium battery cells. The tests were carried out both in nitrogen and in air with different SOCs. The presentation shows the main results of these tests. T2 - 7th International Battery Production Conference (IBPC) CY - Braunschweig, Germany DA - 27.11.2024 KW - Consequneces KW - Electrical Energy Storage KW - Sodium-ion battery KW - Gas release KW - SIB PY - 2024 AN - OPUS4-62178 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisermann, R. A1 - Esterl, F. A1 - Schuchardt, M. A1 - Breithaupt, Mathias A1 - Plath, R. T1 - Distributed acoustic/vibration sensing: Towards advanced transformer condition monitoring N2 - A novel method for transformer vibration monitoring using intensity-based distributed acoustic/vibration sensing (DAS/DVS) is presented. Fibre optic sensors were fully integrated into an oil-filled medium voltage distribution transformer. Opencircuit in-situ measurements were carried out using a single and three-phase supply with an electrical power of up to 30 kVA. Spectral analysis of the mechanical vibrations were performed by measuring the frequency response of the transformer using plain fibre- and transducer-based DVS approaches. The results were compared with the spectra of a microphone mounted on the outside of the transformer housing and the electrical measurements on the high voltage side. Using the fibre optic DVS based monitoring we were able to detect changes in operating power and frequency. Further it could be shown, that it is possible to identify anomalous behaviour such as electrical/mechanical noise sources using the determined vibration spectra. T2 - 2024 IEEE International Conference on High Voltage Engineering and Applications (ICHVE) CY - Berlin, Germany DA - 18.08.2024 KW - Distributed acoustic sensing KW - DAS KW - Transformer monitoring PY - 2024 DO - https://doi.org/10.1109/ICHVE61955.2024.10676084 SP - 1 EP - 4 PB - IEEE CY - New York City, New York, USA AN - OPUS4-61798 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisermann, R. T1 - Distributed acoustic/vibration sensing: Towards advanced transformer condition monitoring N2 - A novel method for transformer vibration monitoring using intensity-based distributed acoustic/vibration sensing (DAS/DVS) is presented. Fibre optic sensors were fully integrated into an oil-filled medium voltage distribution transformer. Opencircuit in-situ measurements were carried out using a single and three-phase supply with an electrical power of up to 30 kVA. Spectral analysis of the mechanical vibrations were performed by measuring the frequency response of the transformer using plain fibre- and transducer-based DVS approaches. The results were compared with the spectra of a microphone mounted on the outside of the transformer housing and the electrical measurements on the high voltage side. Using the fibre optic DVS based monitoring we were able to detect changes in operating power and frequency. Further it could be shown, that it is possible to identify anomalous behaviour such as electrical/mechanical noise sources using the determined vibration spectra. T2 - 2024 IEEE International Conference on High Voltage Engineering and Applications (ICHVE) CY - Berlin, Germany DA - 18.08.2024 KW - Distributed acoustic sensing KW - Condition monitoring KW - Transformer monitoring PY - 2024 AN - OPUS4-61799 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Román Healy Corominas, Francesco Piccolo T1 - Sulfur Spillover on Carbon Materials and its Relevance for Metall-Sulfur Solid-State Batteries N2 - Lithium-sulfur batteries are commonly assembled using a composite material containing porous carbon and sulfur as the cathode. While much work has been done on the design of such high performance composites, the interaction between sulfur and carbon is poorly unterstood. Here we provide further evidence that sulfur and porous carbon undergo a spontaneous reaction at room temperature, recently described as "sulfur spillover". Thermal measurements, XRD, XAS and EPR are used to provide insight into the interaction energy and structure of sulfur after spillover. We also show that the effect may cause a loss in cell voltage by about 70 mV. T2 - 11th Workshop Lithium-Sulfur Batteries CY - Dresden, Germany DA - 11.11.2024 KW - Sulfur Spillover KW - Metal-Sulfur Solid-State Batteries KW - TAM IV KW - XRD KW - XAS KW - EPR PY - 2024 AN - OPUS4-61736 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwarz, Irina A1 - Rieck, Arielle T1 - Valorization of carbon dioxide by electrocatalytic reduction coupled to acetogens via multiple electron carriers (Ecat-acetogens) N2 - To alleviate CO2 emissions and their impact on climate change, converting carbon dioxide into valuable products such as multi-carbon organic chemicals is of great importance. CO2 can be converted via different pathways such as electrochemical, photo-electrochemical and biological etc. Each approach offers distinct merits but also certain challenges in terms of process efficiency, product selectivity and implementation at scale etc. Therefore, developing coupled CO2 conversion systems, for instance bioelectrochemical reactors, can potentially address some of those challenges.[1] In this work, the focus is on developing cost-efficient, biocompatible, and high activity porous M-N-C catalysts with M = Ni and Co that are atomically dispersed as NiN4 and CoN4 active sites in porous carbon matrix. Ni- and Co-N-Cs are prepared by active-site imprinting approach using Mg as an imprinter.[2][3] Pyrolysis of Mg-N-C is carried out in a salt-melt at high temperatures (≥ 800 oC) and followed by an exchange with Ni or Co at low temperatures. N2-sorption of the materials reveal a micro-mesoporous structure with high surface areas (> 1000 m2 g-1) and a mass-transport enabling pore system. Extended X-ray absorption fine structure (EXAFS) reveal the existence of atomically dispersed single atom active sites with defined active site structure. A variety of Ni-N-Cs and Co-N-Cs were tested for CO2R activity in a rotating disc electrode (RDE) setup, showing high activity and selectivity towards CO2R versus the competing HER. Subsequently, these catalysts were implemented in a home-made bio-electrocatalytical system (BES) consisting of a bioreactor coupled to a CO2 electrolysis cell. Here, CO2 is first electrochemically converted to CO in the electrolysis cell which is then directly fed to bacteria (Clostridium ragsdalei) in bioreactor who further metabolize it to valuable carbon compounds such as acetate. In the BES, partial pressures of CO reached a maximum of 5.7 mbar and that of hydrogen was 2.7 mbar after 30 h. A specific exponential bacterial growth rate of 0.16 h-1 was observed with acetate formation rate of 1.8 mg L-1 h-1 and an acetate concentration of 0.103 g L-1 corresponding to acetate formation rate of 0.73 mmol d-1. As will be discussed in greater details in this talk, we have successfully demonstrated the validity of a coupled bio-electrocatalytical system concept operating with Co- and Ni-N-C catalysts for CO2 conversion. T2 - Joint SPP Conference CY - Jena, Germany DA - 06.11.2024 KW - CO2 Reduktion KW - Bioelectrocatalytical system PY - 2024 AN - OPUS4-61993 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwarz, Irina A1 - Rieck, Arielle T1 - Valorization of carbon dioxide by electrocatalytic reduction coupled to acetogens via multiple electron carriers (Ecat-acetogens) N2 - For the realization of a sustainable energy economy, it is of great importance to develop CO2 -neutral methods producing multi-carbon organic chemicals used as feedstock as well as carbon-neutral fuels by CO2 capture and conversion. In this work, a bio-electrocatalytical system (BES) consisting of a bioreactor coupled to a CO2 electrolysis cell is established. CO2 is first electrochemically converted to CO in electrolysis cell which is then directly fed to bacteria (acetogens) to further metabolize it to valuable carbon compounds such as acetate. The objective of this study is to develop cost-efficient, biocompatible and high activity electrocatalysts that can selectively convert CO2 to CO. Porous nitrogen-doped carbons containing atomically dispersed Ni and Co (Ni or Co-N-Cs) are prepared by active-site imprinting approach. First, synthesis of Mg- or Zn-N-C was carried out through pyrolysis of precursors in a salt melt followed by exchange with Ni or Co. N2-sorption porosimetry of the materials reveal a micro-mesoporous structure with high surface areas (> 1000 m2 g-1) and a mass-transport enabling pore system. Extended X-ray absorption fine structure (EXAFS) reveal the existence of single atom sites with no formation of nanoparticles. A variety of Ni-N-Cs and Co-N-Cs were tested for CO2R activity in a rotating disc electrode (RDE) setup, showing high activity (Tafel slopes range from 77 – 130 mV/decade) and selectivity towards CO2R versus the competing HER. Before operation in the BES, first tests were performed in a single cell. Significantly increased current was detected in the CO2R test in CO2-saturated electrolyte vs. in N2 -saturated electrolyte indirectly proving formation of carbon monoxide (CO). Transfer of the electrolysis cell operation into the BES proved to be successful. For biotic operation, the BES was inoculated with Clostridium ragsdalei. Partial pressures pCO reached a maximum of 5.7 mbar and pH2 was 2.7 mbar after 30h. The reduction of partial pressures is interpreted as the consumption of the gases by C.ragsdalei. We report a specific exponential growth rate of 0.16 h-1, acetate formation rate of 1.8 mg L-1 h-1 and an acetate concetration of 0.103 g L-1 corresponding to acetate formation rate of 0.73 mmol d-1.In this work we successfully demonstrated an integrated bio-electrocatalytic system (BES) to convert CO2 into value-added chemicals. The usage of a Co- and Ni-N-Cs as the reduction catalyst within the BES allowed production of CO and H2 with relative selectivity for CO resulting in the growth of Clostridium ragsdalei and acetate production. T2 - Joint SPP Conference CY - Jena, Germany DA - 06.11.2023 KW - Bioelectrocatalytical system PY - 2023 AN - OPUS4-61995 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwarz, Irina A1 - Rieck, Arielle T1 - Valorization of carbon dioxide by electrocatalytic reduction coupled to acetogens via multiple electron carriers (Ecat-acetogens) N2 - To alleviate CO2 emissions and their impact on climate change, converting carbon dioxide into valuable products such as multi-carbon organic chemicals is of great importance. CO2 can be converted via different pathways such as electrochemical, photo-electrochemical and biological etc. Each approach offers distinct merits but also certain challenges in terms of process efficiency, product selectivity and implementation at scale etc. Therefore, developing coupled CO2 conversion systems, for instance bioelectrochemical reactors, can potentially address some of those challenges.[1] In this work, the focus is on developing cost-efficient, biocompatible, and high activity porous M-N-C catalysts with M = Ni and Co that are atomically dispersed as NiN4 and CoN4 active sites in porous carbon matrix. Ni- and Co-N-Cs are prepared by active-site imprinting approach using Mg as an imprinter.[2][3] Pyrolysis of Mg-N-C is carried out in a salt-melt at high temperatures (≥ 800 oC) and followed by an exchange with Ni or Co at low temperatures. N2-sorption of the materials reveal a micro-mesoporous structure with high surface areas (> 1000 m2 g-1) and a mass-transport enabling pore system. Extended X-ray absorption fine structure (EXAFS) reveal the existence of atomically dispersed single atom active sites with defined active site structure. A variety of Ni-N-Cs and Co-N-Cs were tested for CO2R activity in a rotating disc electrode (RDE) setup, showing high activity and selectivity towards CO2R versus the competing HER. Subsequently, these catalysts were implemented in a home-made bio-electrocatalytical system (BES) consisting of a bioreactor coupled to a CO2 electrolysis cell. Here, CO2 is first electrochemically converted to CO in the electrolysis cell which is then directly fed to bacteria (Clostridium ragsdalei) in bioreactor who further metabolize it to valuable carbon compounds such as acetate. In the BES, partial pressures of CO reached a maximum of 5.7 mbar and that of hydrogen was 2.7 mbar after 30 h. A specific exponential bacterial growth rate of 0.16 h-1 was observed with acetate formation rate of 1.8 mg L-1 h-1 and an acetate concentration of 0.103 g L-1 corresponding to acetate formation rate of 0.73 mmol d-1. As will be discussed in greater details in this talk, we have successfully demonstrated the validity of a coupled bio-electrocatalytical system concept operating with Co- and Ni-N-C catalysts for CO2 conversion. T2 - eBiotech Workshop Week + Status Seminar CY - Jena, Germany DA - 19.03.2023 KW - Bioelectrocatalytical system PY - 2023 AN - OPUS4-61997 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Spindlegger, Anna A1 - Slotyuk, Lyubov A1 - Jandric, Aleksander A1 - De Souza, Ricardo Gabbay A1 - Prenner, Stefanie A1 - Part, Florian T1 - Environmental performance of second-life lithium-ion batteries repurposed from electric vehicles for household storage systems N2 - Repurposing lithium-ion batteries has proven to be a promising solution to address the rising number of end-of-life batteries that can be used for second-life energy storage systems and thus extend their service life. While previous research has provided valuable insights into the environmental benefits of battery repurposing, there is still a need to examine the repurposing process more thoroughly, in order to make well-informed decisions on the implementation of second-life battery storage systems. Therefore, this study examines the influence of different repurposing strategies on the environmental performance of second-life battery energy storage systems. A life cycle assessment was conducted, analysing four repurposing cases relating to the exchange of components, namely i) new battery management system and module casing (Base case), ii) new battery management system and reuse of module casing (Case 1), iii) new module casing and reuse of battery management system (Case 2) and iv) reuse of module casing and battery management system (Case 3). These impacts were compared to a storage system with new batteries, to determine the potential environmental benefits and identify the most suitable repurposing strategy. Our findings demonstrate significant environmental benefits of second-life battery energy storage systems across various impact categories and repurposing cases. The Base case and Case 1 resulted in environmental benefits across all impact categories. The highest benefits were observed for metal depletion with savings of 58 % and 61 %, respectively. Increased savings were obtained for Case 2 and Case 3. However, environmental drawbacks were identified for freshwater and marine ecotoxicity. In particular, Case 2 resulted in the highest drawbacks of -22 % and -16 %, respectively. These can be attributed to the allocation procedure, particularly affecting the recycling credits of battery management system recycling. The full allocation of end-of-life impacts and consequently the recycling credits to the second-life battery has not only led to a substantial increase in overall savings, but also resulted in impact categories that originally had disadvantages becoming those with the highest environmental savings. This study demonstrates the importance of carefully selecting repurposing strategies for second-life energy storage systems to maximize their environmental benefits and avoid drawbacks. Additionally, the results highlight the substantial influence of allocation procedures on overall environmental impacts, underscoring the need for clearer methodological guidance on addressing the multifunctionality of repurposed batteries. KW - Life cycle assessment KW - Repurposing KW - Second-life battery KW - Lithium-ion battery KW - Battery energy storage system KW - Circular economy PY - 2025 DO - https://doi.org/10.1016/j.spc.2025.01.003 SN - 2352-5509 VL - 54 SP - 227 EP - 240 PB - Elsevier CY - Amsterdam AN - OPUS4-62940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Alphonse, Amal A1 - Hintermüller, Michael A1 - Kister, Alexander A1 - Lun, Chin Hang A1 - Sirotenko, Clemens T1 - A neural network approach to learning solutions of a class of elliptic variational inequalities N2 - We develop a weak adversarial approach to solving obstacle problems using neural networks. By employing (generalised) regularised gap functions and their properties we rewrite the obstacle problem (which is an elliptic variational inequality) as a minmax problem, providing a natural formulation amenable to learning. Our approach, in contrast to much of the literature, does not require the elliptic operator to be symmetric. We provide an error analysis for suitable discretisations of the continuous problem, estimating in particular the approximation and statistical errors. Parametrising the solution and test function as neural networks, we apply a modified gradient descent ascent algorithm to treat the problem and conclude the paper with various examples and experiments. Our solution algorithm is in particular able to easily handle obstacle problems that feature biactivity (or lack of strict complementarity), a situation that poses difficulty for traditional numerical methods. KW - Obstacle Problems KW - Numerical Analysis KW - Optimization and Control KW - Simulation PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-622160 DO - https://doi.org/10.48550/arXiv.2411.18565 SP - 1 EP - 38 AN - OPUS4-62216 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Amano, Kofi Owusu Ansah A1 - Tschirschwitz, Rico A1 - Gimadieva, Elena A1 - Köhler, Florian A1 - Krause, Ulrich T1 - Thermal runaway and explosibility of the gas release from 18650 sodium-ion cells of NFM chemistry N2 - The present study investigates the thermal runaway behaviour and explosibility of the gas mixture released from sodium-ion batteries (SIBs). A total of 30 tests comprising two test series were performed using 18650 SIBs with a NaNi1/3Fe1/3Mn1/3O2 (NFM) chemistry. The cells of SOC level = 0 %, 25 %, 50 %, 75 % and 100 % were subjected to thermal abuse inside a 10 L pressurized reaction vessel. In test series 1, the tests were performed in an air atmosphere. In test series 2, an inert atmosphere was used. First, the total amount of gas released from the SIBs was calculated based on the temperature and pressure measured in the reaction vessel. Subsequently, a gas composition analysis was performed using a Fourier-transformed infrared (FTIR) spectrometer. This study revealed that the thermal runaway in SIBs could be categorized into four phases. At the onset of thermal runaway, the thermal runaway-induced explosion of the cells resulted in a rate of temperature rise ranging from 2 K/s to 70 K/s. The investigation further revealed a peak reaction temperature of 415 ◦C and a maximum pressure of 4 bar could be reached at thermal runaway in the 10 L vessel. The gas release of up to 5 ± 0.3 L (4 ± 0.2 L/Ah, 1.3 ± 0.1 L/Wh) from test series 1 and 2.4 ± 0.2 L (2 ± 0.1 L/Ah, 0.53 ± 0.04 L/Wh) from test series 2 showed a dependence on SOC and failure environment used. By applying Le Chatelier's mixing rule, the measured gas release from the air atmosphere showed a calculated lower explosion limit and upper explosion limit values of 4.8 % and 24 % in volume fraction, respectively. KW - Sodium-ion battery KW - Thermal runaway KW - Gas release KW - Gas explosion KW - Explosion limit PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631782 DO - https://doi.org/10.1016/j.est.2025.116614 SN - 2352-152X VL - 122 SP - 1 EP - 16 PB - Elsevier Ltd. AN - OPUS4-63178 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Sarah-K. T1 - Second Life Verwendungen - Untersuchungen und erste Erfahrungen mit einem Ausbildungsdemonstrator N2 - Der Vortrag gibt zunächst einen Themeneinstieg in den Bereich der Second-Life-Batterien sowie rechtliche und technische Grundlagen zu Lebenszyklus und Alterung. Im Weiteren werden experimentelle Ergebnisse aus Versuchen zum thermischen Durchgehen mit Batteriemodulen aus dem BMBF-Vorhaben SEE-2L vorgestellt. Darüber hinaus wird ein eigens entwickelter Ausbildungsdemonstrators vorgestellt, welcher einen wesentlichen Baustein des Ergebnistransfers aus dem Vorhaben darstellt. T2 - Brände von Lithium-Ionen-Batterien in Elektrofahrzeugen kontrollieren, eindämmen und vorbeugen CY - Essen, Germany DA - 25.03.2025 KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Lithium-Ionen-Batterie KW - Stationäre Energiespeicher KW - Thermisches Durchgehen PY - 2025 AN - OPUS4-63180 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lüders, C. A1 - Kalinka, Gerhard A1 - Li, Wei A1 - Sinapius, M. A1 - Wille, T. T1 - Experimental and numerical multiscale approach to thermally cycled FRP N2 - Due to the different thermal expansion of the constituent materials, cyclic thermal loading of FRP induces alternating stresses in the material at two scales: at the micro scale (level of fibre–matrix-interaction) and at the macro scale (level of the multidirectional laminate). Especially the micro scale effect is not comprehensively investigated yet. Additionally, computational investigations mostly neglect this effect due to the homogenous modelling of the composite material. As this effect is assumed to significantly contribute to the fatigue of FRP at thermal loads, the present paper suggests an experimental and numerical multiscale approach including Experiments at the different involved material scales to separately observe the effects acting at these scales. The approach also includes numerical modelling for each scale to complement the knowledge gained from the Experiments and to create a basis for the consideration of the micro effect even in macroscopic fatigue models treating homogeneous modelled composites. The main focus of the contribution is to bring the overall Approach up for discussion, rather than to present the multiscale modelling details. KW - Fatigue KW - Thermal cycling KW - Fibre reinforced plastic KW - Cryogenic KW - Carbon Fibre KW - Epoxy Resin PY - 2020 DO - https://doi.org/10.1016/j.compstruct.2020.112303 SN - 0263-8223 VL - 244 SP - 112303 PB - Elsevier Ltd. CY - Niederlande AN - OPUS4-50844 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique T1 - Data-Driven Spectrochemical Methods for Elemental and Isotopic Analysis N2 - High-resolution optical spectrometers generate spectra containing tens of thousands of data points per sample. Picometre-scale isotope shifts, matrix-induced line broadening, and strong inter-feature correlations render classical peak fitting unreliable. Current analytical challenges, therefore, require rigorous algorithms able to expose latent structure, quantify uncertainty, and remain chemically interpretable. The research program presented in this lecture integrates state-of-the-art spectrochemical instrumentation with mathematically disciplined data models. Principal Component Analysis and Partial Least Squares provide chemically meaningful latent variables, while gradient-boosted decision trees or deep neural networks (ANNDL) capture residual non-linearity without sacrificing traceability. All models are trained on isotope-enriched or synthetically generated spectra and distributed with full validation workflows. T2 - Chemisches Institutskolloquium, Humboldt-Universität zu Berlin CY - Berlin, Germany DA - 21.05.2025 KW - Spectrochemistry KW - Isotopes KW - Machine learning KW - Battery KW - Data fusion PY - 2025 AN - OPUS4-63488 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique T1 - Lithium isotope fractionation as a diagnostic tool for aging lithium-ion batteries N2 - Lithium-ion batteries (LIBs) are central to modern energy storage technologies, powering applications from portable electronics to electric vehicles and grid storage systems. Their popularity comes from their high energy density, efficiency, and extended cycle life. However, over time, various aging mechanisms lead to capacity loss, increased internal resistance, and, ultimately, battery failure. Understanding and predicting these aging processes is crucial for enhancing the reliability and longevity of LIBs. This necessity makes the development of advanced diagnostic tools essential. This study uses plasma-based spectrometry techniques to explore lithium isotope fractionation (LIF) as a predictive tool for monitoring LIB aging and degradation. Mass spectrometric techniques —including MC-ICP-MS, LA-ICP-MS, and MICAP-MS— were employed to analyze lithium isotopic composition in both new and aged lithium cobalt oxide (LCO) cells, including lab-made coin cells and commercial batteries. An isotopic fractionation was identified during electrochemical cycling: 6Li migrates towards the anode, while 7Li accumulates in the cathode. These isotopic patterns correlate with structural degradation, including solid electrolyte interphase (SEI) growth and crack formation, as confirmed by FIB-SEM, XANES, and EXAFS analyses. This correlation demonstrates that LIF aligns with key aging mechanisms in model coin cells and commercial batteries, such as capacity fade and impedance growth. LIF provides a powerful diagnostic tool for battery health monitoring and aging prediction by linking isotopic fractionation to structural degradation. This approach offers significant potential to extend battery lifespan and improve the reliability of energy storage systems. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - Isotope KW - Lithium KW - Battery aging KW - Degradation KW - Fractionation KW - Battery PY - 2025 AN - OPUS4-63487 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hahn, Sarah-K. A1 - Tschirschwitz, Rico A1 - Pascal, Schmitz A1 - Krause, Ulrich T1 - Forschung zur Sicherheit von Elektroenergiespeichern N2 - Bei der Umstellung der Energieversorgung von fossilen auf „erneuerbare“ Energieträger kommt der Zwischenspeicherung von Energie eine entscheidende Bedeutung zu. Volatile Energieträger wie Solar- und Windenergie werden in Abhängigkeit der Tageszeit und des Wetters gewonnen, sodass die Energiegewinnung starken Schwankungen unterliegt und gleichzeitig begrenzt vorhersagbar ist. Hinzu kommt, dass der Zeitpunkt von Spitzenwerten verfügbarer Energie (z. B. Sommernachmittag bei Wind und Sonnenschein) nur bedingt mit den Zeiten des größten Energiebedarfs (z. B. Winterabend mit niedrigen Temperaturen) übereinstimmt. KW - Auswirkungsbetrachtungen KW - Thermisches Durchgehen KW - Stationäre Energiespeicher KW - Lithium-Ionen-Batterie KW - Elektrische Energiespeicher PY - 2025 UR - https://www.schadenprisma.de/archiv/artikel/forschung-zur-sicherheit-von-elektroenergiespeichern/ SN - 0343-3560 VL - 2025 IS - 2 SP - 14 EP - 17 PB - Institut für Schadenverhütung und Schadenforschung der öffentlichen Versicherer e.V. (IFS) CY - Kiel AN - OPUS4-63994 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique T1 - On developments of continuum source atomic and molecular absorption spectrometry N2 - Der Bunsen-Kirchhoff-Preis 2022 wurde am 23.06.2022 anlässlich der analytica conference in München an Dr. Carlos Abad verliehen - in Anerkennung seiner exzellenten Entwicklungen im Bereich der continuum source atomic absorption spectrometry (CS-AAS). Dr. Carlos Abad ist ein herausragender Experte auf dem Gebiet der Atom- und molekularen Absorptionsspektrometrie. insbesondere trug er maßgeblich zur substanziellen Weiterentwicklung von Echelle-Spektrometern für die CS-AAS bei. So gelang es, einen quantitativen Zugang zu Elementen wie Bor, Chlor, Fluor und Schwefel, mittels AAS zu erreichen. Erstmals demonstriert Dr. Carlos Abad am Beispiel eines Zr-Modifier, dass durch die Zeitauflösung der eingesetzten Echelle-Systeme mechanistische Untersuchungen zur Wirkung des Modifiers im Graphitrohrofen möglich sind. Besonders hervorzuheben sind seine Arbeiten zum Einsatz der CS-AAS für die Analyse von Isotopen, die eine Genauigkeit aufweist, welche an die der Multikollektor-induktiv gekoppelten Plasma-Massenspektrometrie (MC-ICP-MS) heranreicht. Damit ergeben sich völlig neue Einsatzmöglichkeiten für technologisch hochrelevante Applikationen, wie z.B. die Untersuchung der Alterung von Lithium-Batterien oder die Lithium-Analyse in Blutserum. T2 - Analytica Conference: Bunsen-Kirchhoff-Preis 2022 der Deutsche Arbeitskreis für Analytische Spektroskopie (DAAS) CY - Munich, Germany DA - 23.06.2022 KW - Isotopes KW - Fluorine KW - Halogens KW - Non-metals KW - HR-CS-MAS KW - HR-CS-AAS KW - Bunsen-Kirchhoff-Preis KW - Continuum source atomic absorption spectrometry KW - Zr-Modifier KW - Graphite furnace KW - Lithium PY - 2022 AN - OPUS4-56500 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Graeber, Gustav T1 - Paste-like interlayers in alkali-metal battery anodes N2 - Giving an introduction to high-temperature batteries with molten alkali-metal anodes and solid electroyltes. Presenting the research on alkali-metal tensiometry and the study about wetting interactions between liquid alkali-metal alloys and porous carbon hosts. T2 - AG Christina Roth Seminar CY - Bayreuth, Germany DA - 16.07.2025 KW - Battery PY - 2025 AN - OPUS4-64069 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Graeber, Gustav T1 - Graeber Lab for Energy Research at Tag der Chemie in Adlershof N2 - Highlighting recent progress in the Graeber Lab for Energy Research in the areas of alkali-metal tensiometry, alkali-metal anodes in contact with solid electrolytes, sulfur cathodes and solid electrolyte synthesis. T2 - Tag der Chemie in Adlershof 2025 CY - Berlin, Germany DA - 03.07.2025 KW - Batterie PY - 2025 AN - OPUS4-64068 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Graeber, Gustav T1 - Paste-like alkali-metal anodes in contact with solid electroytes N2 - Explaining the motivation of the BMFTR ANaBatt project. Presenting recent advances in alkali metal tensiometry and characterization of alkali-metal wetting in porous carbon materials via X-ray computed tomography. T2 - Sodium Battery Symposium 6 CY - Dresden, Germany DA - 03.09.2025 KW - Battery PY - 2025 AN - OPUS4-64070 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böttcher, Nils T1 - Neue Brandlasten - neue Aufgaben für die Feuerwehr N2 - Die zunehmende Verbreitung von elektrischen Energiespeicher und Flüssiggasspeicher ermöglichen eine erfolgreiche Transition zu einer CO2 neutralen Energieversorgung. Allerdings bringen neue Energiespeicher mit hohen Energiedichten auch zusätzliche Herausforderungen für die Feuerwehr der Zukunft mit sich. Insbesondere Lithiumbatterien können bei falscher Handhabung zum thermischen Durchgehen führen. Dies kann katastrophale Auswirkungen mit sich bringen. Der Umstieg auf Wasserstoff als neuen Energieträger birgt ebenfalls zusätzliche Risiken und Unsicherheiten für die Einsatzkräfte. Daher ist die Lageeinschätzung und der möglichen Gefahren am Einsatzort für die Feuerwehrkräfte essenziell notwendig. T2 - Transfer on fire CY - Ludwigsfelde, Germany DA - 14.08.2024 KW - Lithiumbatterien KW - Sicherheit von Energieträgern KW - Gefahrguttransport PY - 2024 AN - OPUS4-61502 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böttcher, Nils T1 - Untersuchungen für den Transport gekühlter Batterien Vorstellung des Nageltests N2 - Im Zusammenhang mit den Untersuchungen zu den Möglichkeiten von gekühlten Transporten von Lithiumbatterien werden unterschiedliche Zerstörungsmethoden vorgestellt und diskutiert. Insbesondere wird dabei das neu entwickelte Nageltool und die vorläufigen Untersuchungen für den Einfluss von Ultratiefkühlung auf unbeschädigte Lithiumbatterien vorgestellt. T2 - ERFA-Verpackungen CY - Berlin, Germany DA - 22.09.2022 KW - Lithiumbatterien KW - Thermal Runaway KW - Gefahrguttransport KW - Nageltest PY - 2022 AN - OPUS4-56759 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böttcher, Nils T1 - Untersuchungen für den Transport gekühlter Batterien Vorstellung des Nageltests N2 - Im Zusammenhang mit den Untersuchungen zu den Möglichkeiten von gekühlten Transporten von Lithiumbatterien werden unterschiedliche Zerstörungsmethoden vorgestellt und diskutiert. Insbesondere wird dabei das neu entwickelte Nageltool vorgestellt. T2 - Fachkonferenz Lithiumbatterien CY - Goettingen, Germany DA - 28.04.2022 KW - Lithiumbatterien KW - Thermal Runaway KW - Gefahrguttransport KW - Nageltest PY - 2022 AN - OPUS4-56758 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, Wuyi A1 - Mehmood, Asad A1 - Ali, Ghulam A1 - Liu, Hui A1 - Chai, Liyuan A1 - Wu, Jun A1 - Liu, Min T1 - Nickel Nanocluster-Stabilized Unsaturated Ni–N3 Atomic Sites for Efficient CO2-to-CO Electrolysis at Industrial-Level Current N2 - Unsaturated Ni single-atom catalysts (SACs), Ni-Nx (x=1,2,3), have been investigated to break the conventional Ni-N4 structural limitation and provide more unoccupied 3d orbitals for CO2 reduction reaction (CO2RR) intermediates adsorption, but their intrinsically low structural stability has seriously hindered their applications. Here, we developed a strategy by integrating Ni nanoclusters to stabilize unsaturated Ni-N3 atomic sites for efficient CO2 electroreduction to CO at industrial-level current. Density Functional Theory (DFT) calculations revealed that the incorporation of Ni nanocluster effectively stabilizes the unsaturated Ni-N3 atomic sites and modulates their electronic structure to enhance the adsorption of the key intermediate *COOH during CO2RR. Guided by these insights, we prepared an optimal composite catalyst, Ni6@Ni-N3, which features a Ni6N6 nanocluster surrounded by six Ni-N3 single atoms sites, through low-temperature pyrolysis. The morphology and coordinative structure of Ni6@Ni-N3 were confirmed by an aberration-corrected transmission electron microscope (AC-TEM) and X-ray absorption spectroscopy (XAS). As a result, Ni6@Ni-N3 demonstrated a remarkably high CO Faradaic efficiency (FECO) of 99.7 % and a turnover frequency (TOF) of 83984.2 h−1 at 500 mA cm−2 under −1.15 VRHE, much better than those of Ni-N4 with a lower FECO of 86 % at 100 mA cm−2 and a TOF of 39309.9 h−1under identical potential. XAS analyses of Ni6@Ni-N3 before and after long-term CO2RR testing confirmed the excellent stability of its coordinative environment. This work highlights a generalizable approach for stabilizing unsaturated single-atom catalysts, paving the way for their application in high-performance CO2RR. KW - Electrochemical CO2 conversion KW - Single atom catalysts KW - CO2 electrolysis PY - 2025 DO - https://doi.org/10.1002/anie.202424552 SN - 1521-3773 VL - 64 IS - 13 SP - 1 EP - 10 PB - Wiley-VCH CY - Weinheim AN - OPUS4-62926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Graeber, Gustav T1 - Batterieforschung an der Humboldt-Universität zu Berlin - Selbstvorstellung beim KLiB N2 - Selbstvorstellung der Batterieforschungsaktivitäten der HU Berlin in Kooperation mit lokalen Partnern wie der BAM im Rahmen eines Netzwerktreffens. Fokus auf die Forschung in der Arbeitsgruppe Graeber zu Festkörperbatterien und der Arbeitsgruppe Adelhelm zu Natrium-Ionen-Batterien. T2 - KLiB Netzwerktreffen CY - Frankfurt, Germany DA - 26.03.2025 KW - Batterie PY - 2025 AN - OPUS4-63350 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Graeber, Gustav T1 - Graeber Lab for Energy Research - Overview N2 - Vorstellung der Forschungsaktivitäten der AG Graeber an der HU Berlin und an der BAM. Diese beinhalten die Erforschung grundlegender Benetzungsphänomene von Alkalimetallen, deren Anwendung in Festkörperbatterien mit pastenartigen Alkalimetallanoden, die Erforschung von Schwefelkathoden, die Synthese von Natrium-leitenden Festelektrolyten sowie die Entwicklung von Hydrogel-basierten Batterien. T2 - BMBF BattFutur NanoMatFutur Netzwerktreffen 2025 CY - Berlin, Germany DA - 24.02.2025 KW - Batterie PY - 2025 AN - OPUS4-63361 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Qi, Naiyu A1 - Somaskandan, Rachana A1 - Graeber, Gustav T1 - High-Precision Surface Tension Measurements of Sodium, Potassium, and Their Alloys via Du Noüy Ring Tensiometry N2 - The development of post-lithium-ion batteries has sparked significant interest in alkali-metal anodes, particularly sodium (Na), potassium (K), and sodium−potassium (Na−K) alloys. Na−K alloys are promising for partially liquid anodes due to their unique low melting points. A critical factor influencing Na−K-based anode performance is wetting behavior, which governs electrical conductivity, mechanical contact, and long-term stability. At the heart of wetting lies surface tension, a fundamental property of solid−liquid− gas interactions. However, the surface tension of alkali metals and their alloys, particularly Na−K systems, remains poorly understood due to experimental and theoretical challenges. This study bridged these gaps by employing Du Noüy ring tensiometry for the first time in alkali-metal systems to measure the surface tension of Na, K, and Na−K alloys across temperatures from ambient to 180 °C. A key innovation in this work is the development of the push-in Du Noüy method, which provided significantly higher precision and reliability compared to the traditional pull-out technique, without requiring a correction factor. The measured surface tension decreased with increasing temperature for the studied Na−K alloys. For instance, for a eutectic Na−K mixture, the surface tension decreases from 121.7 mN m−1 to 112.2 mN m−1 when increasing the temperature from ambient to 180 °C. Additionally, this study presented the first use of Gibbs free energy minimization to model the surface tension of the Na−K system. The robust method significantly enhanced the predictive accuracy compared to the previous simplified model, reducing deviations from 25% to 2%. Our findings reveal that surface tension increases with sodium mole fraction in the bulk phase, yet the surface monolayer remains potassium-rich, indicating non-ideal surface behavior. This study deepens the understanding of alkali-metal wetting behavior, providing valuable insights for designing optimized interfaces in next-generation semi-solid alkali-metal batteries. KW - Sodium−potassium alloy KW - Liquid-metal anodes KW - Alkali metal KW - Batteries KW - Surface tension PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630102 DO - https://doi.org/10.1021/acsami.5c02183 SN - 1944-8252 VL - 17 IS - 17 SP - 25985 EP - 25995 PB - American Chemical Society (ACS) CY - Washington, DC AN - OPUS4-63010 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -