PhD projects

Block copolymers can undergo self-assembly to form a new class of microparticles termed polymer Cubosomes. Polymer cubosomes consist of a periodic channel system, they are open porous, and have a high loading capacity. I will use polymer cubosomes either as template for metal oxides and transition metals or convert them directly to mesoporous carbon. The resulting materials will be then tested as novel anode materials for Lithium-ion batteries.

The PhD project is being conducted at the Chair of Polymer materials for electrochemical storage.

My work will focus on the synthesis and characterisation of novel Na⁺ conductors with high ionic conductivity and thermodynamic stability.

The PhD project will be conducted as part of the 4SBATT project at the Chair of Inorganic Active Materials for Electrochemical Energy Storage.

This project investigates the transport of electrons and ions in battery electrode materials as a function of their structure and grain size. We are synthesizing materials with different dimensionality of the percolation channels and particle sizes, to unveil the impact of confinement on both carrier types by studying their mobilities. First-principles calculations and machine learning will be used to construct a multi-scale model of the transport of both carriers in these structures. This approach will uncover ways to link or decouple electron and ion transport, hinting at future rational design criteria.

The PhD project is being conducted at the Chair of Inorganic Active Materials for Electrochemical Energy Storage within the SFB Multitrans - Project B01.

In my dissertation, I am investigating thermal problems in batteries at the microstructure level. We are particularly interested in how heat transport can be designed by using intrinsic thermally anisotropic materials. Graphite, as one of the most commonly used anode materials, is an example of such a material. The targeted alignment of graphite particles can improve heat dissipation in the battery. In addition, hot spots can be avoided, which in turn reduces the degradation of the active battery material.
I also work with laser-based methods and IR thermography for the non-destructive evaluation of battery materials and battery cells. The next step is to extend our setup to extract the thermal properties of calendered electrodes. Together with detailed information about the microstructure, we can then specifically modify the heat transport in the electrode.

The PhD project is being conducted at the Chair of Physical Chemistry I.

The aim of our research project is to establish an in-situ/operando solid-state NMR spectroscopic setup for batteries and energy materials. NMR spectroscopyn as an analytical method is sensitive to both, local structure and the mobility of ions in the materials.

This PhD project is supervised by Dr. Helen Grüninger at the Chair of Inorganic Chemistry III.

My project focuses on investigating electron transfer kinetics and the mechanisms of coupled electrochemical reactions, using electrochemical impedance spectroscopy (EIS). To achieve this, I will benchmark the implementation and analysis of impedance spectra using model systems and then extend its use to complex reactions relevant for energy conversion and energy storage.

The PhD project is being conducted at the Chair of Electrochemistry.

The project aims to improve the characterisation of silicon-containing anode materials for lithium-ion batteries through a holistic approach. By synthesising new composite materials, particularly Si-rGO composites, the performance and stability of the batteries will be optimised This will be achieved through the implementation of layered electrodes, which will then be electrochemically characterised using cycling, CV, differential capacitance analysis and impedance spectroscopy. In addition, physicochemical characterisation techniques such as SEM, TEM, FTIR, Raman, XRD, XPS and elemental analysis are used to gain a comprehensive insight into the structure and composition of the materials. The combination of these areas will provide insights into the de- and lithiation and degradation processes of the synthesised materials and electrodes, which will contribute to the further development of more powerful lithium-ion batteries.

The PhD project is being conducted at the Chair of Electrochemical Process Engineering.

The conflict between high charging rates and battery lifetime is still a challenge in the development of electric vehicles and power-tools. It is necessary to identify operating conditions that trigger degradation processes to be able to combine fast charging with a long battery lifetime. Therefore, non-invasive sensing techniques that monitor real-time dynamics within the battery are crucial. With Operando EIS or dynamic electrochemical impedance spectroscopy (DEIS), impedance data is recorded under charge or discharge to gain information about the battery under operation. By examining impedance anomalies, evidence of battery damage can be found during operation. This method should be used to develop a fast-charging control of lithium-ion batteries based on impedance signals.

The PhD project is being conducted at the Chair of Electrical Energy Systems.

In the iron redox flow battery (IRFB), elemental iron is deposited on the negative electrode, which, together with the parasitic hydrogen evolution reaction (HER), leads to reduced charging efficiency. Promising results are expected with regard to the influence of various parameters, such as additives or the electrode structure, on iron deposition and hydrogen evolution. In cooperation with the Junior Professorship for Battery Management Methods, the experiment will be linked to the simulation in order to gain an even better understanding of processes in the battery and to systematically optimise these processes.

The doctoral project is being carried out at the Chair of Materials Process Engineering.

In case of overheating due to overcharging or a mechanical defect of lithium-ion batteries there is a safety risk due to the thermally unstable electrolyte. Contact with atmospheric oxygen or humidity leads to oxidation of the electrolyte and thus to heat generation, which starts a chain reaction known as thermal runaway. The battery separator as a passive, safety-relevant component in LIBs ensures the spatial separation of anode and cathode and thus prevents internal short circuits. As a temperature-stable alternative to state-of-the-art polymer separators, glass is to be used as separator material. High thermal and chemical resistance as well as good wettability with the battery electrolyte predestine glass for this application.
At Keylab Glass Technology, separators based on glass fibers and glass particles are produced and characterized using colloidal processes. In extensive electrochemical testing procedure, the performance and stability of the glass separators was proven in test cells. However, the higher density of glass reduces the gravimetric energy density of the battery cell, so that the focus of the current research is on reducing the thickness of the separator.

The PhD project is being conducted at the KeyLab Glass Technology.

This research project investigates the feasibility of using Powder Aerosol Deposition (PAD) to fabricate micrometer-thin, dense, and ion-conductive NaSICON (Sodium Super Ionic Conductor) membranes for next-generation sodium-based solid-state batteries (SSSBs). These batteries offer several advantages over traditional lithium-ion batteries, including the use of more abundant and environmentally friendly sodium and the potential for higher energy densities and improved safety due to the solid electrolyte. The project focuses on the optimization of process conditions and parameters for PAD-NaSICON membranes, rather than material development.

The project focuses on three key aspects: achieving dense, sodium-conducting NaSICON membranes using PAD, understanding the relationship between the resulting microstructure and achievable room-temperature ionic conductivity, and exploring the potential of moderate annealing to enhance conductivity and reduce interface resistance. Additionally, researchers aim to demonstrate the feasibility of constructing sodium-conducting cells entirely with PAD-fabricated functional layers. The ultimate goal is to assemble an all-solid-state sodium battery by sequentially depositing cathode and solid electrolyte layers via PAD and to utilize Na metal as anode.

The PhD project is being conducted at the Chair of Functional Materials.