Nanocomposites as anode materials for lithium ion batteries: Synthesis, thermodynamic characterization and modeling of nanoparticular silicon dispersed in SiCN(O) and SiCO-based matrices (DFG SPP 1473 WENDELIB)
In the subproject 8 „Nanocomposites as anode materials for lithium ion batteries: Synthesis, thermodynamic characterization and modeling of nanoparticular silicon dispersed in SiCN(O) and SiCO-based matrices“ of the DFG SPP 1473 WENDELIB, we investigate amorphous and crystalline silicon nanoparticles homogeneously dispersed in a SiCN(O)- and SiCO-based ceramic derived from polysilazane and polysiloxane.
The electrochemical performance of the resulting SiCN(O)/Si and SiCO/Si material is studied in combination with commercial electrolytes and metallic lithium as reference/counter electrode material. The existence of intermediate compounds of the constituents is explored by a combination of quantum mechanical calculations, calorimetric measurements and thermodynamic modeling. We investigate the thermodynamics of the aforementioned materials by using computational methods (Calphad approach) for clarifying phase reactions. Additionally, we perform high temperature solution calorimetry to measure enthalpies of formation for the materials of interest. Ultimately, the new anode material shall be tested in a complete battery, where commercial cathode materials (LiCoO2, LiFePO4) will be used.
The MM group specifically deals with
- first-principle based structure-search of low-energy model-geometries of amorphous Li-Si, SiOC and SiCN
- thermodynamics and phase evolution of Li-Si systems
- intercalation kinetics of Li in Si, Li-Si, SiOC and SiCN
- development of bond-order potentials for large-scale classical molecular-dynamics simulations of composite structures
Beteiligte MM Mitarbeiter
Dr. Jochen Rohrer und Prof. Karsten Albe
Dispersive Feststoffe, Institut für Materialwissenschaften, TU Darmstadt
Institut für Angewandte Materialien – Angewandte Werkstoffphysik, KIT Karlsruhe