Preparation and characterization of carbon aerogels as electrode materials for battery applications

Kurzfassung

The production of lithium ion batteries is very resource-intensive and undergoes continuous growth in the face of increasing electrification in the energy and mobility sector as well as other areas that contribute to our current living standard. Next to lithium, graphite is one of the main materials required for battery production and is currently mined on a big scale from natural deposits causing the emission of toxic nanoscopic particles. On the other hand, preparation of synthetic graphite causes high carbon emissions as it requires a high energy-input.[1] In order to replace graphite and reduce current production effects on the environment, this work deals with the preparation and characterization of novel composite materials applicable in anodes. These composites consist of carbonized chitosan aerogels and carbon black that has been recovered and highly purified in a sophisticated process from end-of-life tyres, thus contributing to an overall more sustainable rechargeable battery. In this work, carbon aerogels have been obtained via carbonization of previously prepared chitosan aerogels[2]. The influence of various preparation conditions (applied temperature, atmosphere) on the pore structure (scanning electron microscopy, surface area, pore volume, pore size distribution), elemental composition and electrical conductivity has been studied and compared. Various approaches for material activation such as the application of CO2 have been tested. Furthermore, the influence of post-synthetic processing steps (milling, application of pressure) performed during electrode production has been investigated on the quest towards an optimised anode material. [1] Gomez-Martin, A.; Martinez-Fernandez, J.; Ruttert, M.; Heckmann, A.; Winter, M.; Placke, T.; Ramirez-Rico, J., Iron-Catalyzed Graphitic Carbon Materials from Biomass Resources as Anodes for Lithium-Ion Batteries. ChemSusChem 2018, 11 (16), 2776-2787. [2] Preibisch, I.; Niemeyer, P.; Yusufoglu, Y.; Gurikov, P.; Milow, B.; Smirnova, I. Polysaccharide-Based Aerogel Bead Production via Jet Cutting Method. Materials 2018, 11, 1287.