Battery Research

Motivation: Electrodes in Li-Ion and Post-Li-Ion batteries are heavily influenced by their respective microstructure. Mapping the spatial distribution of degradation products within the microstructure offers a unique insight into the degradation mechanism of composite electrode materials, paving the way for optimizing the performance.

Aim: The aim of this project is to reconstruct the 3D microstructure of electrodes using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and GANs (General advisory networks) on large 2D ToF-SIMS images. The reconstructed microstructures will then be subject to digital characterization and finite element analysis to simulate the influence of degradation on key performance parameters such as conductivity and overpotential.

Notes: Depending on the preference, the project can be focused on the data science/simulation part or the experimental part such as performing the ToF-SIMS measurements and building the corresponding solid-state-battery cells. Either way you should be enthusiastic about software, large datasets and surface analytics. Of course, both German and English-Speakers are welcome!

Contact: Alexander Weiß, alexander.weiss and Prof. Dr. Anja Henss, anja.henss

Hintergrund / Motivation: Polymer electrolytes are a promising electrolyte class for solid state batteries. Reactions of polymer electrolytes with lithium metal play a critical role in developement of reservoir free solid state batteries and their potential longivity.

Ziel / Aim: Linking the properties of polymer electrolytes to the speed of lithium metal consumption after plating (see figure). By varying the parameters of polymer electrolytes (molecular weight, salt concentration, temperature,…) you will investigate the reaction speed of polymer electrolytes with lithium metal by a novel electrochemical technique (CTTA).

Hinweise / Notes: You will be preparing coin cells under inert conditions in a glovebox. Attention to detail and manual dexterity are advised. For an extended project, e.g. master thesis, there is also an opportunity to analyze the morphology of plated lithium and composition of the resulting reaction layer using surface analytical techniques.

Contact: Timo Weintraut, Timo.Weintraut; Prof. Dr. Anja Henss, anja.henss

Motivation: Na-S solid-state batteries are one of the most promising alternatives to Li-ion batteries. However, their development is still at an early stage and the design of well-functioning electrodes has a critical role. A potential solution to improve their performances includes the use of metal sulfides (e.g. iron disulfide FeS2) as active material in the cathode.

Aim: The object is to experimentally investigate FeS2 based cathodes in Na-S solid state battery. For this purpose, battery cells will be built and characterized with both electrochemical and analytical methods.

Notes: You should enjoy working in the laboratory, have initiative and enjoy learning new topics and techniques. You should be interested in physical chemistry and research in the field of advanced material for sustainable energy applications. We offer you an stimulating project in an active and international working group in which you can develop your skills.

Contact: Matilde Pavan, matilde.pavan; Prof. Dr. Anja Henss, anja.henss

Motivation: PEO-based polymer electrolytes are interesting materials for sodium solid-state batteries due to their safety and compatibility with sodium salts. However, their ionic conductivity and interfacial properties still need to be improved and better understood. However, the solid electrolyte interphase plays a crucial role in the battery performance.

Aim: This project aims to study PEO-based polymer electrolytes for sodium solid-state batteries, focusing on their preparation, characterization, and application in solid-state battery cells using electrochemical and analytical methods. The project will exploit CTTA technique, coupled with post-mortem analysis with ToF-SIMS and XPS, to understand the composition and the properties of the interphase.

Notes: The project involves experimental laboratory work under inert atmosphere in a glovebox, and cell production, in coin cell or pouch cell setup. If you are interested in the topic, you can always contact us to ask more informations, ask or propose some topic-related research projects too.

Contact: Tommaso Mavolo, tommaso.mavolo ; Prof. Dr. Anja Henss, anja.henss

Hintergrund / Motivation: Die Charakterisierung moderner Dünnschichtsysteme erfordert Analyseverfahren mit hoher räumlicher Auflösung und materialspezifischer Sensitivität. Elektronenbasierte Methoden im REM liefern eine Vielzahl komplementärer Signale, deren Potenzial jedoch noch nicht vollständig ausgeschöpft ist.

Ziel / Aim: Ziel ist die Weiterentwicklung und Kombination elektronenbasierter Analyseverfahren zur verbesserten Untersuchung von Dünnschichtsystemen. Dabei sollen insbesondere Tiefeninformation, Materialkontrast und kristallographische Eigenschaften gezielt zugänglich gemacht werden. Neue Auswerteansätze, z. B. auf Basis von Machine Learning, spielen dabei eine zentrale Rolle.

Hinweise / Notes: Die Arbeit kombiniert experimentelle Methoden (SE, BSE, EDX, EBSD, Auger) mit fortgeschrittener Datenanalyse. Ein Fokus liegt auf Querschnittsanalysen sowie perspektivisch auf operando-fähigen Messungen. Das Projekt richtet sich an Studierende mit Interesse an Physik, Materialwissenschaft und datengetriebenen Methoden.

Contact: Dr. Till Fuchs, till.fuchs; Prof. Dr. Anja Henss, anja.henss