Solid-state batteries based on both lithium-ion and lithium-sulfur cells are regarded as promising future energy storage systems, particularly for mobility applications. In solid-state batteries, solid polymers or oxides are used as solid electrolytes. Compared to liquid electrolytes, solid electrolytes provide significantly higher safety levels and simpler cell structures. Moreover, solid electrolytes can be used in combination with active materials that are currently problematic for continuous operation. The use of metallic lithium as the anode and the elimination of the separator are also expected to double the energy density, which is very important in mobility application (vehicle and aircraft). Furthermore, the higher mechanical load-bearing capacity of solid-state batteries offers a key advantage with regard to the use in aircraft.
Due to all these reasons, solid-state batteries have been proved as a key future focus topic. However, there are still some challenges which need to be overcome. On the one hand, these battery systems require significantly more complex materials in comparison to conventional lithium-ion batteries. For example, in order to ensure stability against solid electrolytes, it could be a possibility to apply coatings in the nanometer range to active material particles. For the production of these materials, processes are being developed in the Battery LabFactory Braunschweig, bearing in mind the production of sufficient quantities of material for further processing into larger cells. On the other hand, the production of solid-state battery electrodes is currently limited to the laboratory scale, since the direct transfer of processing techniques for conventional lithium-ion batteries is not possible. With this aim, new processes for manufacturing the electrodes are being researched depending on the used materials.
