TY - JOUR A1 - Naumann, Kathrin A1 - Tichter, Tim A1 - Nielsen, Rasmus S. A1 - Seger, Brian A1 - Hansen, Ole A1 - Chorkendorff, Ib A1 - Vesborg, Peter C. K. T1 - Protection Materials on III–V Semiconductors for Photoelectrochemical CO Reduction N2 - Tantalum oxide (TaOx) and amorphous titanium dioxide (TiO2) are employed as protection materials for commercial GaInP/GaAs/Ge triple-junction solar cells to facilitate the unbiased photoelectrochemical reduction of carbon monoxide on nanostructured copper particles. It has been found that a photoelectrode protected by a 150 nm-thick layer of TiO2, capped with 8 nm TaOx, and decorated with copper nanocubes in the size of 150 nm can successfully drive the photoelectrochemical conversion of carbon monoxide to ethylene. Implemented into a photoelectrochemical flow reactor, which continuously supplies the active interface with CO-saturated electrolyte, the device achieves a faradaic efficiency of 24% under AM1.5G conditions. Direct attachment of the copper nanocubes to a protection layer of TiO2 in the absence of TaOx results in a strong hydrogen evolution reaction (HER) and no CO reduction products are found. This unexpected loss in selectivity is studied via post-operando X-ray photoemission spectroscopy and ion-scattering spectroscopy. No modifications in the redox state of TiO2 orsigns of H intercalation are found, while the preferential redeposition of small Cu nanoparticles is considered possible. This increasein HER appears specific for TiO2, as additional, purely electroanalytical experiments using tantalum oxide or carbon as a support layer for Cu nanocubes can produce ethylene effectively. KW - Photoelectrochemistry KW - Carbon Monoxide Reduction KW - Protection Material KW - Multi‐junction KW - Copper Catalyst PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618712 DO - https://doi.org/10.1021/acs.jpcc.4c04782 SP - 1 EP - 10 PB - American Chemical Society (ACS) AN - OPUS4-61871 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Prenner, Stefanie A1 - Part, Florian A1 - Jandric, Aleksander A1 - Bordes, Arnaud A1 - Leonhardt, Robert A1 - Jung-Waclik, Sabine A1 - Huber-Humer, Marion ED - Djebali, Ridha T1 - Enabling Circular Business Models: Preconditions and Key Performance Indicators for the Market Launch of Repurposed Second‐Life Lithium‐Ion Batteries From Electric Vehicles N2 - With the rise of electric vehicles (EVs) and thus lithium‐ion batteries (LIBs), the number of end‐of‐life (EoL) LIBs after their first life in EVs is about to increase significantly. These end‐of‐first‐life (EoFL) EV LIBs still have sufficient energy density for less‐demanding second‐life applications like stationary battery energy storage systems (BESSs) or mobile applications (e.g., forklifts, tools). Repurposing EoFL EV LIBs extends their lifespan, offering sustainability benefits and supporting several United Nations (UN) Sustainable Development Goals (SDGs). However, prevailing market entry barriers, such as high repurposing costs, little information on battery history and aging, or lacking performance indicators, hinder the widespread implementation of second‐life applications. Thus, this study aims to identify preconditions for considering and selecting useful EoFL LIBs and to determine key performance indicators (KPIs) to minimize economic risks for a successful second‐life market launch. KPIs were rated according to importance using a Likert scale, and reference values were introduced. A mixed‐methods approach, using expert interviews, an exploratory workshop, and an online survey, was applied. Twelve important preconditions were identified, with the “availability of information on battery specification” and “compliance with standards and regulations” considered very important. In addition, 12 KPIs were derived, covering six economic, three environmental, and three technical and safety‐related indicators. The KPIs “state of safety (SoS)” and “resource savings (Rsav)” were rated as highly important. Overall, the findings provide performance measurement guidance for repurposing companies, facilitating the market launch and adoption of second‐life applications. Future research can build on these results and investigate variations among different battery types, ultimately promoting a circular economy. KW - Lithium-Ion battery KW - Key performance indicators KW - Circular economy KW - Electric vehicle KW - Sustainability PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-619167 DO - https://doi.org/10.1155/er/8331870 SP - 1 EP - 19 PB - Wiley AN - OPUS4-61916 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Prenner, Stefanie A1 - Part, Florian A1 - Jung-Waclik, Sabine A1 - Bordes, Arnaud A1 - Leonhardt, Robert A1 - Jandric, Aleksander A1 - Schmidt, Anita A1 - Huber-Humer, Marion T1 - Barriers and framework conditions for the market entry of second-life lithium-ion batteries from electric vehicles N2 - Transition to circular economy for lithium-ion batteries used in electric vehicles requires integrating multiple stages of the value cycle. However, strategies aimed at extending the lifetime of batteries are not yet sufficiently considered within the European battery industry, particularly regarding repurposing. Using second-life lithium-ion batteries (SLBs) before subsequent recycling can offer several advantages, such as the development of sustainable business models, the reduction of emissions, and alignment with UN Sustainable Development Goals 7, 12, and 13. Using expert and problem-centred interviews along with an exploratory workshop, this study guides stakeholders in the battery sector by illustrating the necessary changes for a more holistic circular economy. Moreover, an extended political, economic, social, technological, environmental, legal, and additionally safety-related (PESSTEL) analysis approach is carried out, which has not yet been used in this context. In this process, barriers, as well as necessary institutional framework conditions and organisational requirements for a successful market entry of SLB applications are investigated. Among others, key barriers relate to the competition with first-life applications and safety concerns. SLBs require high manual labour costs for repurposing, along with expenses for expired warranties and re-certifications. Ownership structures in traditional business models often result in SLBs and their corresponding usage data staying under the control of the manufacturers. Market viability, however, requires a level playing field for both first-life and second-life operators as well as circular battery and data-sharing business models. Gathering data on the ageing performance and performing improved safety testing according to test protocols facilitates the reliable assessment of SLBs. KW - Electric vehicle KW - Circular economy KW - Market entry barrier KW - Repurposing KW - Second-life lithium-ion battery KW - Second-life battery energy storage system PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-614543 DO - https://doi.org/10.1016/j.heliyon.2024.e37423 VL - 10 IS - 18 SP - 1 EP - 15 PB - Elsevier Ltd. AN - OPUS4-61454 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Caianiello, Carlo A1 - Tichter, Tim A1 - Arenas, Luis F. A1 - Wilhelm, René T1 - Toward Symmetric Organic Aqueous Flow Batteries: Triarylamine‐Based Bipolar Molecules and Their Characterization via an Extended Koutecký–Levich Analysis N2 - Symmetric organic flow batteries (SOFBs) can potentially address membrane crossover problems by employing bipolar redox‐active organic molecules (BROMs). Herein, a triarylamine (TAA) skeleton was chosen as a posolyte moiety for a new class of bipolar molecules for pH‐neutral aqueous flow batteries (FBs). Pyridinium and viologen derivatives were tethered to the posolyte moiety, and the new compounds were characterized. Cyclic voltammetry revealed that only viologen with a highly hydrophilic substituent, connected to the TAA moiety via a Zincke reaction, could be reversibly reduced. Varying the supporting electrolyte concentration on the selected derivative revealed water solubility as a challenge for further development. The selected derivative, MeO‐TPA‐Vi‐DMAE, was subjected to hydrodynamic voltammetry, and a modified Koutecký–Levich analysis was developed to investigate the observed potential‐dependent currents at the hydrodynamically dominated region, which are often seen with redox‐active organic molecules. This model discarded a purely Ohmic effect, showing a useful Levich slope at a certain overpotential before the onset of a secondary reaction. TAA‐based BROMs hold promise for pH‐neutral aqueous SOFBs, and the results will guide the design of new derivatives. The three‐term Koutecký–Levich relation here introduced will be useful not only to develop BROM‐based FBs but will most likely appeal to a much broader audience. KW - Redox Flow Batteries KW - Koutecký-Levich Analysis KW - Rotating Disc Electrode KW - Redox-active Bipolar Molecules KW - Electrode Kinetics PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631476 DO - https://doi.org/10.1002/chem.202500815 SN - 1521-3765 SP - 1 EP - 15 PB - Wiley VHC-Verlag AN - OPUS4-63147 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tichter, Tim A1 - Tichter, Alex A1 - Andrae, Dirk A1 - Roth, Christina T1 - Simulating cyclic voltammetry at rough electrodes by the digital-simulation–deconvolution–convolution algorithm N2 - The influence of electrode roughness on diffusional cyclic voltammetry (CV) is investigated from a theoretical perspective. For this purpose, the digital-simulation–deconvolution–convolution (DSDC) algorithm, initially developed for the simulation of CV at porous electrodes, is subjected to three substantial modifications. First, by employing adaptive numerical resolution and sample volumina, the computational demand of the digital simulation (DS) step is reduced significantly. Second, by modifying the Douglas–Gunn algorithm of the DS-step to operate on an arbitrarily incremented spatial grid perpendicular to the macroscopically planar electrode surface, the bulk of the fluid can be treated with an exponentially increasing spatial discretization which uses computational power even more efficiently. The third modification is an optimization of the computationally demanding deconvolution step which is used to extract the mass-transfer function from the data computed in the DS-step. This, initially recursive procedure, is replaced by a three-step sequence consisting of (I) a numerical Laplace transformation (NLT) on an exponentially expanding time-grid, (II) a Laplace-domain integration (LDI) and finally (III) a numerical inversion of Laplace transformation (NILT) using the Gaver–Stehfest (GS) inversion formula. Based on this novel strategy for CV simulation, the effects of electrode roughness are thoroughly investigated. It is demonstrated that for an ideally reversible reaction the effects of electrode roughness on the CV response are insignificant at common experimental timescales. In contrast, for scenarios with electrochemically quasi-reversible (or irreversible) kinetics, the apparent rate constants are allegedly upscaled by the area ratio 𝜓 = 𝐴rough∕𝐴planar . This manifests in a lower peak-to-peak separation without a distortion of the shape of the voltammetric profile. This behavior is finally explained in a quantitative manner in terms of convolution-sums and mass-transfer functions which ultimately puts the parameter electrode roughness into the semianalytical framework of convolutive modeling. KW - Rough electrodes KW - Electrode kinetics and Peak-to-Peak separation KW - Vanadium redox-flow batteries KW - Convolutive modeling KW - Digital-simulation KW - Numerical inversion of Laplace transformation KW - Gaver–Stehfest inversion formula PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-614620 DO - https://doi.org/10.1016/j.electacta.2024.145175 VL - 508 SP - 1 EP - 17 PB - Elsevier B.V. AN - OPUS4-61462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dayani, Shahabeddin A1 - Markötter, Henning A1 - Krug von Nidda, Jonas A1 - Schmidt, Anita A1 - Bruno, Giovanni T1 - Quantification of the Deep Discharge Induced Asymmetric Copper Deposition in Lithium‐Ion Cells by Operando Synchrotron X‐Ray Tomography N2 - AbstractLithium‐ion cells connected in series are prone to an electrical safety risk called overdischarge. This paper presents a comprehensive investigation of the overdischarge phenomenon in lithium‐ion cells using operando nondestructive imaging. The study focuses on understanding the behavior of copper dissolution and deposition during overdischarge, which can lead to irreversible capacity loss and internal short‐circuits. By utilizing synchrotron X‐ray computed tomography (SXCT), the concentration of dissolved and deposited copper per surface area is quantified as a function of depth of discharge, confirming previous findings. The results also highlight for the first time a nonuniform distribution pattern for copper deposition on the cathode. This research provides insights for safer battery cell design. KW - Lithium Ion Batteries KW - Deep Discharge KW - Computer Tomography KW - Copper Deposition KW - Litium Ion Cells PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-592717 DO - https://doi.org/10.1002/admt.202301246 SP - 1 EP - 7 PB - Wiley AN - OPUS4-59271 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Böttcher, Nils A1 - Dayani, Shahabeddin A1 - Markötter, Henning A1 - Bau, Alexander A1 - Setzchen, Max A1 - Schmidt, Anita A1 - Kowal, Julia A1 - Krug von Nidda, Jonas T1 - High Precision Nail‐Penetration Setup for the Controlled Thermal Runaway Initiation of Lithium‐Ion Cells at Very Low Temperatures N2 - A high precision nail‐penetration (NP) tool for characterizing the mechanically induced thermal‐runaway (TR) of lithium‐ion battery (LIB) cells in a defined range of temperatures down to −140 °C was developed. To understand the cell specific behavior at low temperatures aiming at the determination of safe handling conditions, different scenarios are analyzed. First, accuracy tests of the NP‐tool regarding motion and penetration depth are conducted with cylindrical cells at different temperatures. Thus, postmortem computer tomographic (CT) images are compared to the data measured with the newly integrated 3‐axis force sensor which is further combined with a high‐resolution position sensor. The herein developed setup allows evaluation of the NP‐metrics at an accuracy of ±1 pierced electrode layer without CT‐scans. Further NP examinations at 20 °C of fully charged cylindrical lithium nickel manganese cobalt oxide cells reveal a reproducible minimum damage as a reliable TR‐trigger. Moreover, NP‐tests at low temperature disclose a relation of the short circuit conductivity and TR‐reactions during subsequent rethermalization to room temperature. Finally, the implementation of a novel fixture for a controlled very fast cooling of LIB‐cells during critical damage opens the way to investigate the individual steps during a TR and, thus, to gain important information of the specific TR‐mechanism of different LIB‐cells. KW - Battery Safety KW - High-precision nail penetration KW - Lithium-ion batteries KW - Abuse testing KW - Thermal runaway PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598127 DO - https://doi.org/10.1002/ente.202301379 SN - 2194-4288 SP - 1 EP - 13 PB - Wiley VHC-Verlag AN - OPUS4-59812 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Leonhardt, Robert A1 - Böttcher, Nils A1 - Dayani, Shahabeddin A1 - Rieck, Arielle A1 - Markötter, Henning A1 - Schmidt, Anita A1 - Kowal, Julia A1 - Tichter, Tim A1 - Krug von Nidda, Jonas T1 - Exploring the electrochemical and physical stability of lithium-ion cells exposed to liquid nitrogen N2 - The transport and storage of lithium-ion (Li-ion) batteries — damaged or in an undefined state — is a major safety concern for regulatory institutions, transportation companies, and manufacturers. Since (electro)chemical reactivity is exponentially temperature-dependent, cooling such batteries is an obvious measure for increasing their safety. The present study explores the effect of cryogenic freezing on the electrochemical and physical stability of Li-ion cells. For this purpose, three different types of cells were repeatedly exposed to liquid nitrogen (LN2). Before and after each cooling cycle, electrical and electrochemical measurements were conducted to assess the impact of the individual freezing steps. While the electrochemical behavior of the cells did not change significantly upon exposure to LN2 , it became apparent that a non-negligible number of cells suffered from physical changes (swelling) and functional failures. The latter defect was found to be caused by the current interrupt device of the cylindrical cells. This safety mechanism is triggered by the overpressure of expanding nitrogen which enters the cells at cryogenic temperatures. This study underlines that the widely accepted reversibility of LN2 -cooling on a material scale does not allow for a direct extrapolation toward the physical integrity of full cells. Since nitrogen enters the cell at cryogenic temperatures and expands upon rethermalization, it can cause an internal overpressure. This can, in turn, lead to mechanical damage to the cell. Consequently, a more appropriate temperature condition — less extreme than direct LN2 exposure — needs to be found KW - Lithium-ion battery KW - LN2 cooling KW - Battery characterization PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599248 DO - https://doi.org/10.1016/j.est.2024.111650 VL - 89 SP - 1 EP - 7 PB - Elsevier B.V. AN - OPUS4-59924 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Böttcher, Nils A1 - Dayani, Shahabeddin A1 - Markötter, Henning A1 - Schmidt, Anita A1 - Kowal, J. A1 - Lu, Y. A1 - Krug von Nidda, Jonas A1 - Bruno, Giovanni T1 - Visualization of stepwise electrode decomposition in a nail penetrated commercial lithium-ion cell using low-temperature synchrotron X-ray computed tomography N2 - The transition towards zero carbon emissions in power generation hinges on the integration of efficient electrical energy storage systems, with lithium-ion batteries (LIBs) positioned as a pivotal technology. While generally safe, deviations in their operational guidelines due to manufacturing defects or misuse can lead to critical safety concerns, notably thermal runaway (TR) events. Internal short circuits (ISCs) are primary initiators of TR within LIBs. For abuse testing, ISCs are often triggered by nail penetration. This study explores the morphological changes and mechanisms underlying ISC-induced TR in LIBs using operando synchrotron X-ray computed tomography (SXCT) at subzero temperatures. A novel cryogenic setup was developed to control a stepwise temperature increase in the damaged sample while monitoring electrochemical characteristics and simultaneously enabling acquisition of high-resolution SXCT images. The findings reveal that conducting nail penetration at minus 80°C prevents immediate TR, enabling detailed analysis of subsequent structural and electrochemical behavior during controlled thawing. Thus, the initiation of TR processes at localized ISC sites has been observed, evidenced by voltage fluctuations and morphological changes, such as cathode material cracking and decomposition. These results underscore the importance of temperature control in mitigating TR risks and provide critical insights into the internal dynamics of LIBs under abusive conditions. The developed cryogenic SXCT methodology offers a powerful tool for non-destructive, high-resolution investigation of battery failure mechanisms, contributing to the enhancement of LIB safety. KW - Tomography KW - X-ray imaging KW - Lithium-ion battery PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611327 DO - https://doi.org/10.1016/j.jpowsour.2024.235472 VL - 623 SP - 1 EP - 10 PB - Elsevier CY - New York, NY AN - OPUS4-61132 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Böttcher, Nils A1 - Sander, Luise A1 - Ulbricht, Alexander A1 - Widjaja, Martinus Putra A1 - Fellinger, Tim-Patrick A1 - Schmidt, Anita A1 - Krug von Nidda, Jonas T1 - Sodium-ion battery research @ BAM (I): investigating the thermal runaway behaviour of commercial sodium-ion battery cells N2 - Commercially available sodium-ion battery (SIB) cells, with energy densities comparable to lithium-ion battery (LIB) cells based on LiFePO4, were investigated regarding their safety behaviour under thermal abuse conditions. Tests were carried out in an inert atmosphere. The SIB-cells went into thermal runaway (TR), intriguingly, even at a rather low state of charge of 30%. The TR-event was coupled with a pronounced jelly roll ejection, challenging the interpretation of the TR-diagrams. These findings highlight the necessity of incorporating SIB-cells into the ongoing safety classification discussions for LIB-cells. KW - Sodium Ion Batteries KW - Thermal Runaway KW - Battery safety PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-647652 DO - https://doi.org/10.1039/d5se00687b SN - 2398-4902 VL - 9 IS - 21 SP - 5832 EP - 5838 PB - Royal Society of Chemistry (RSC) AN - OPUS4-64765 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -