Solid-State-Chemistries for Batteries at AIT

Research and development efforts in industry and academia are highly focused on the progress of solid-state batteries (SSBs), to increase safety and performance of currently established lithium-ion batteries (LIBs). Solid electrolytes (SEs) have suffered from low ionic conductivity (0.1 mS cm-1) compared to liquid electrolytes (1 mS cm-1). Therefore, great efforts have been made to address this issue resulting in novel materials that even outperform liquid electrolytes. However, ionic conductivity is only one of several parameters that need to be addressed to enable SSBs. This includes electrochemical and chemical stability, processability, and costs. Some materials such as polymers, gels and ceramics used as solid electrolytes cover some of these parameters, however, none fulfill all of them at once. At Austrian Institute of Technology (AIT) different materials are evaluated for their applicability in SSBs:
- Polymer electrolytes (PEs), they excel in processability, however they show low room temperature ion conductivity. AIT directs efforts to improve PE formulations and anode and cathode films [1].
- Gel electrolytes (GEs), they show high ionic conductivity and good processability, AIT focuses on the improvement of the electrode-electrolyte interfaces [2].
- Ceramic electrolytes (CEs), they have the highest ionic conductivities, nevertheless, their processability is challenging, to address this issue AIT works on developing oxides-, sulfides- and halides-based electrolytes [3].
A compromise on key parameters is essential for obtaining SSBs suitable for complying with the safety, sustainability, and energy storage demands of today and tomorrow.

References
[1] N. Zhang, A. Beutl, K. Rajinovic, J. Kahr, M. Jahn, M. Nestoridi, Scalable preparation of practical 1 Ah all-solid-state lithium-ion batteries cells and their abuse tests, Journal of Energy Storage 59 (2023) 106547.
[2] H. Kühnelt, A. Beutl, F. Mastropierro, F. Laurin, S. Willrodt, A. Bismarck, M. Guida, F. Romano, Structural Batteries for Aeronautic Applications—State of the Art, Research Gaps and Technology Development Needs, Aerospace 2022, 9(1), 7.
[3] A. Tron, R. Hamid, N. Zhang, A. Paolella, P. Wulfert-Holzmann, V. Kolotygin, P. López-Aranguren, A. Beutl, Film processing of Li6PS5Cl electrolyte using different binders and their combinations, Journal of Energy Storage 2023, 66, 107480.