Micro- to Nanoscale Investigation of Interfacial Processes in Solid-State Batteries with Hybrid Electrolytes to Elucidate the Lithium Transport

• Applicants: Dr. Anja Henß; Dr. Felix Richter
• Subject Area: Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 496844749

The project MiNaBatt targets the understanding of the chemistry and transfer processes at the interfaces between polymer electrolytes and inorganic solid electrolytes. This is essential for the functioning of solid-state batteries with hybrid electrolytes, which promise to improve the performance of electrochemical energy storage devices. Thus, this research gives fundamental insight into the lithium transport between two electrolyte types with different lithium conduction mechanisms. The lithium transfer at the interface is complicated by the fact that most material combinations react with each other to form an interphase of degradation products, which significantly influence the lithium transfer across the interface. This drastically affects cell performance and it is vital to understand the underlying mechanisms.Therefore, MiNaBatt combines the experience of experts in the fields of electrochemistry, interfaces, materials synthesis and SIMS analysis to jointly pursue a systematic investigation into the interfaces of a selection of different combinations of polymer and inorganic solid electrolytes. The sample combinations are chosen to represent different functionality and reactivity of polymer and inorganic solid electrolytes. The selected samples cover a range from very commonly used combinations, such as PEO- and garnet-type hybrid electrolytes, to less studied electrolytes, such as polyphosphacenes. Our goal is to jointly investigate the interface chemistry at multi-scale dimensions. Therefore, we analyse the morphology and chemical composition of the interface in 2D and 3D with a new instrumental setup for the HIM-SIMS to enable analysis of polymer-inorganic-hybrids with highest lateral resolution. We also apply Hybrid-SIMS measurements with orbitrap analyser to obtain complementary information at high mass resolution. Along with electrochemical measurements of the interface resistance under varying temperature, pressure and current density, we intend to understand the physicochemical principles of lithium transfer through interfaces/interphases in hybrid solid electrolytes.

• DFG Programme: Research Grants
• International Connection: Luxembourg
• Partner Organisation: Fonds National de la Recherche
• Cooperation Partner: Dr. Jean-Nicolas Audinot