TY - CONF A1 - Fellinger, Tim-Patrick T1 - Basics, Challenges and Trends in Electrochemical Energy Storage N2 - In this lecture the fundamental principles of batteries are briefly introduced aligned by the historical development of the technology. The introduction is continued with an overview on current challenges regarding performance, durability, sustainability, cost and safety. Lastly, research trend on approaches to tackle the challenges are discussed by selected examples. T2 - Basics, Challenges and Trends in Electrochemical Energy Storage CY - Cottbus, Germany DA - 15.09.2025 KW - Batteries KW - Electrochemistry KW - Energy Materials PY - 2025 AN - OPUS4-64919 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Core-shell type carbon anodes for na-ion batteries N2 - Increasing prices of the material basis for lithium-ion batteries caused by limited production capacities or resource abundance has led to a renewed interest in sodium ion batteries (SIBs). Therein, amorphous disordered carbons such as hard carbons (HCs) are promising candidates for high-capacity negative electrode materials in SIBs. Their high capacities, however, are often accompanied with high irreversible capacity losses during the initial cycles,[1] while low initial losses are mostly accompanied with moderate capacities.[2] In our research we are aiming at morphologically improved carbons to reduce irreversible losses using a core-shell concept, leading to spacial separation of the reversible storage and unfavorable side reactions.[3] We investigated different methods to obtain core-shell structures with improved interfaces to restrict SEI formation to the external particle surface, while leveraging the Na storage potential of porous carbon core materials. With a simple and scalable chemical vapour deposition we obtained a 190-fold decrease in surface roughness, resulting in drastically reduced first cycle losses. Interestingly, the sodiation capacity at the same time increased to 400 mAh/g revealing the interference of excessive SEI formation with the storage process within the particles. T2 - Research Seminar of the Dahn Labs at Dalhousie University CY - Halifax, Canada DA - 27.05.2025 KW - Natrium-Ionen-Batterien KW - Synthetische Anoden KW - Kohlenstoff PY - 2025 AN - OPUS4-64912 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Commercial State-of-the-Art Sodium-Ion Batteries and Perspectives for the Negative Electrode (Anode) N2 - The current strong interest in electromotive mobility and the need to transition to an energy grid with sustainable storage devices has led to a renewed interest in sodium ion batteries (SIBs). Chinese battery manufacturers marketed the first cells, which are commercially available now. We have purchased and investigated two of these early cells to understand their composition and be able to compare to the state-of-the-art in the scientific community. According to our results and the current literature, all commercial cells utilize carbon-based anodes, with the characteristic sloping charge-discharge profile. In the presentation the results will be discussed in context with safety aspect and space for improvement. The latter aspect will be focused on hard carbon anodes. Amorphous disordered carbons such as hard carbons (HCs) are promising candidates for high-capacity negative electrode materials in SIBs. Their high capacities, however, are often accompanied with high irreversible capacity losses during the initial cycles,[1] while low initial losses are accompanied with moderate capacities.[2] In our research we are aiming at morphologically improved carbons to reduce irreversible losses using a core-shell concept.[3, 4] T2 - Eco-Mat Conference 2025 CY - Istanbul, Türkiye DA - 29.07.2025 KW - Natrium-Ionen-Batterien KW - Synthetische Anoden KW - Kohlenstoff PY - 2025 AN - OPUS4-64908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Improved Hard Carbon Anodes for Na-ion Batteries by Interface Modification N2 - The current strong interest in electromotive mobility and the need to transition to an energy grid with sustainable storage devices has led to a renewed interest in sodium ion batteries (SIBs). Amorphous disordered carbons such as hard carbons (HCs) are promising candidates for high-capacity negative electrode materials in SIBs. Their high capacities, however, are often accompanied with high irreversible capacity losses during the initial cycles,[1] while low initial losses are accompanied with moderate capacities.[2] In our research we are aiming at morphologically improved carbons to reduce irreversible losses using a core-shell concept.[3] We investigated different methods to obtain core-shell structures with improved interfaces to restrict SEI formation to the external particle surface, while leveraging the Na storage potential of porous carbon core materials. With a simple and scalable chemical vapour deposition we obtained a 190-fold decrease in surface roughness, resulting in drastically reduced first cycle losses. Interestingly, the sodiation capacity at the same time increased revealing the interference of excessive SEI formation with the storage process within the particles. T2 - ECS Spring Meeting 2025 CY - Montreal, Canada DA - 18.05.2025 KW - Natrium-Ionen-Batterien KW - Synthetische Anoden KW - Kohlenstoff PY - 2025 AN - OPUS4-64911 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Designing Core-Shell Carbon Materials for High-Performance Sodium-Ion Battery Anode N2 - Increasing prices of the material basis for lithium-ion batteries caused by limited production capacities or resource abundance has led to a renewed interest in sodium ion batteries (SIBs). Therein, amorphous disordered carbons such as hard carbons (HCs) are promising candidates for high-capacity negative electrode materials in SIBs. Their high capacities, however, are often accompanied with high irreversible capacity losses during the initial cycles,[1] while low initial losses are mostly accompanied with moderate capacities.[2] In our research we are aiming at morphologically improved carbons to reduce irreversible losses using a core-shell concept, leading to spacial separation of the reversible storage and unfavorable side reactions.[3] We investigated different methods to obtain core-shell structures with improved interfaces to restrict SEI formation to the external particle surface, while leveraging the Na storage potential of porous carbon core materials. With a simple and scalable chemical vapour deposition we obtained a 190-fold decrease in surface roughness, resulting in drastically reduced first cycle losses. Interestingly, the sodiation capacity at the same time increased to 400 mAh/g revealing the interference of excessive SEI formation with the storage process within the particles. T2 - International Carbon Conference 2025 CY - Saint Malo, France DA - 29.06.2025 KW - Sodium-Ion-Batteries KW - Hard Carbons KW - Synthetic Anodes KW - Carbon PY - 2025 AN - OPUS4-64907 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Sustainable energy materials and circularity N2 - Li-ion batteries (LIB) are the dominant energy storage technology and present in electrified transportation, electronic devices as well as robotics. This is due to their high energy density (300 watt-hours per kilogram), low self-discharge (1.5-2% per month), long storage life (10 years) and cyclability (500-2000 cycles). Unfortunately, these batteries require the use of scarce, toxic and unethically resourced materials for their fabrication. Furthermore, it is expected an increase of 26 million units of LIB on electric vehicles by 2030 generating a large amount of waste in a very near future. However, those end-of-life batteries can be considered an important source of metals and materials (electrolytes, binders, anodes) to be reused in other applications or incorporated in the battery supply chain. This also pushes the need to redesign the LIB components and other sustainable technologies using low-cost materials. The focus of this symposium is to bring together experts from around the world to discuss the latest advancements in sustainability of battery technologies and their impact on the future landscape of our society and environment. During the symposium, speakers will present recent research and developments in solving future and present problems derived from the exponential demand of LIB manufacturing T2 - Mat-Sus Spring Meeting 2025 CY - Sevilla, Spain DA - 03.03.2025 KW - CRM-free KW - Sustainability KW - Energy Materials PY - 2025 AN - OPUS4-64915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Molekularsiebende Kohlenstoffe als hochkapazitive und stabile Anoden in Natrium-Ionen-Batterien N2 - In dem Vortrag wird ein Fortschrittsbericht über die laufenden Arbeiten im BMBF-geförderten Verbundprojekt „Dialysorb“ gegeben. Nach einer kurzen Schilderung der Arbeitspaketstruktur und den Arbeitspaketinhalten werden einzelne wissenschaftliche Ergebnisse genannt und kurz diskutiert. So gelang es hier u.a. hochporöse Materialien mittels Gasphasenabscheidung von Kohlenstoffverbindungen derart zu modifizieren, dass nur noch ein Bruchteil der Porosität mittels Gassorption messbar ist. Elektrochemische Sodiierungs-/Dessodiierungsergebnisse deuten darauf hin, dass die Porosität im Kern der Materialien erhalten ist, da die reversible Sodiierungskapazität deutlich erhöht ist. Abschließend werden folgende Arbeitschritte erläutert und der Vortrag zur Diskussion gestellt. T2 - BMBF-Statusmeeting B@TS 2025 CY - Cologne, Germany DA - 07.04.2025 KW - Natrium-Ionen-Batterien KW - Synthetische Anoden KW - Kohlenstoff PY - 2025 AN - OPUS4-64906 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Leveraging the Potential of Na-Ion-Batteries with Tailormade Anodes N2 - Research progress on synthetic hard carbon anodes was suggested as key technology to leverage the potential of sodium ion batteries. The background, progress and market size of sodium ion batteries was presented and the relevance of producing such materials in terms of a business case was suggested. T2 - HWR Entrepreneural Workshop 2025 CY - Berlin, Germany DA - 18.10.2025 KW - Natrium-Ionen-Batterien KW - Synthetische Anoden KW - Kohlenstoff PY - 2025 AN - OPUS4-64909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Bioinspired Electrode Materials N2 - Porous carbon materials are known for their applicability in important areas such as sorption, catalysis and electrochemistry (e.g. fuel cell catalysts, supercapacitor or battery electrodes). It was shown that nitrogen doped carbons (NDCs) act as an inexpensive and highly active non-metal catalyst in the oxygen reduction reaction (ORR), with the potential to reach performances of practical need one day. A key strategy towards improvement for this aim comprises the generation of advantageous porosity, which typically means high surface area and mass transport pores as well as the control over the chemistry of catalytically active sites. My group developed novel sol-gel type strategies that are using molten salts or molten acids as unconventional reaction medium for the porogenesis in doped carbons, thereby revisiting classic activation techniques. Carbon materials with extra high surface area of ~2800 m2 g-1 and pore volumes, up to four times as high as in commercial activated carbons, are obtained. Hierarchical pore systems, like used in nature (leaves, lungs, etc.) facilitate some of the electrochemical performances. Moreover, because of the elements also defining organic matter, also binding motifs can be realized that are reminiscent of proteins/enzymes. We established the pyrolytic template-ion reaction using cations like Mg2+ and Zn2+ to imprint tetrapyrrolic N4 sites (like in the heme molecule), embedded into the carbon structure. The imprinted structure may be utilized as catalytically active site by performing ion-exchange reactions. This way catalytic activity can be tuned for different societal important reactions, but also the defined catalysts structure allows the assignment of structure-performance relations. Other “tricks” that nature uses, are to influence the passage of ions through cell walls, or to expel water molecules from catalytically active sites. I will show some recent work on carbon electrodes used as battery active materials that utilizes similar pathways. T2 - Kolloquium des Instituts für Anorganische und Allgemeine Chermie der Universität Freiburg CY - Freiburg, Germany DA - 04.12.2025 KW - Carbon KW - M-N-C KW - Fuel cell KW - Core-shell KW - Sodium ion battery PY - 2025 AN - OPUS4-65021 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Design, Structure and Performance of Fe-N-C Catalysts Based on Active-Site Imprinting N2 - Atomically dispersed M-N-C catalysts such as Fe-N-Cs are most promising alternatives for precious metal-based catalysts for several energy conversion reactions. Early reports on such materials date back to the 1960´s, when Jasinski pioneered the research based on tetrapyrrolic phthalocyanine macrocycles which were inspired by natural transition metal porphyrin complexes present in enzyme active sites. For decades, the selective synthesis of these catalysts was complicated by the formation of side phases due to the harsh reaction conditions facilitating side phase formation. In 2018, we introduced a mild procedure, which is conservative toward the carbon support and leads to atomically dispersed Fe-N4 site formation at temperatures as low as 80 °C in a wet-chemical step, essentially decoupling the preparation of the N-C backbone from the preparation of the active sites. The key concept therein is the so-called active-site imprinting into the N-C backbone using pyrolytic template ion reactions, allowing for high concentrations of N4 sites resulting in more than 3 at.% of Fe in atomically dispersed phase. Using the same precursor that is used for the preparation of phthalocyanines, we were able to produce atomically-dispersed single-site Fe-N-Cs that consist of tetrapyrrolic FeN4 complexes. The tetrapyrrolic Fe-N-C derivatives are highly active and extraordinary selective electrocatalysts for the oxygen reduction reaction. The well-defined and homogeneous active site structure allows to quantify the intrinsic catalytic activity of the materials in acid and base, reveal insights into the electrocatalytic mechanism and to reveal distinct degradation mechanism upon storage and electrochemical cycling. Herein, the general synthetic strategy of active-site imprinted catalysts will be discussed mainly based on both Mg-ion and Zn-ion templating towards “designed” Fe-N-C catalysts. The tetrapyrrolic active sites will be discussed regarding structure, activity, selectivity and durability. This hopefully stimulates a fruitful discussion of the perspectives in the field. T2 - Chemical Engineering Research Seminar of Higgins Group of McMaster University CY - Hamilton, Canada DA - 29.05.2025 KW - Carbon KW - M-N-C KW - Electrocatalysis KW - Fuel cells PY - 2025 AN - OPUS4-64913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fellinger, Tim-Patrick T1 - Deciphering Structure-Performance Relations of PGM-Free Fe-N-C Electrocatalysts Based on Synthetic Materials Design N2 - Fe-N-C electrocatalysts are very promising alternatives for precious metal-based catalysts for energy conversion reactions.[1-3] Early reports on such materials date back to the 1960´s, when Jasinski pioneered the research based on tetrapyrrolic phthalocyanine macrocycles which were inspired by natural transition metal porphyrin complexes present in enzyme active sites.[3] For decades, the synthesis of these catalysts with a high iron loading was complicated by the formation of side phases due to the harsh reaction conditions facilitating side phase formation. In 2018, we introduced a mild procedure, which is conservative toward the carbon support and leads to active-site formation at low temperatures in a wet-chemical step, essentially decoupling the preparation of the N-C backbone from the preparation of the active sites.[4, 5] The key concept therein is the so-called active-site imprinting into the N-C backbone using pyrolytic template ion reactions.[4][5] Using the same precursor that is used for the preparation of phthalocyanines, we were able not only to produce atomically-dispersed single-phase Fe-N-Cs with a high iron loading, but were also able to selectively form tetrapyrrolic Fe-N4 complexes.[6] The tetrapyrrolic Fe-N-C derivatives are highly active and extraordinary selective electrocatalysts for the oxygen reduction reaction. Deconvolution of morphological effects on the performance allowed to quantify the intrinsic catalytic activity of the materials in acidic and alkaline conditions and gives new insights into the reaction mechanism in alkaline.[7, 8] A distinct degradation mechanism upon storage was found for the tetrapyrrolic sites and new insights on degradation upon fuel cell operation could be obtained.[9, 10] Herein, the general synthetic material design strategy for atomically dispersed catalysts will be discussed based on tetrapyrrolic Fe-N-C catalysts, which will be analyzed for their potential as PGM-free fuel cell catalysts. T2 - Research Seminar of National Institute of Chemical Physics and Biophysics CY - Tallinn, Estonia DA - 29.09.2025 KW - Carbon KW - M-N-C KW - Electrocatalysis KW - Fuel cells PY - 2025 AN - OPUS4-64916 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -