Renewable energy sources (RES) are slowly replacing unsustainable sources such as gasoline and coal, to lead us to a more environmentally sound future. The problem RES are facing is that the energy generation is highly weather-dependent, and therefore inconsistent. Energy storage systems are necessary to guarantee an efficient distribution of energy when it's needed. Battery systems, especially Li-Ion-Batteries (LIBs), are the storage devices of choice currently, due to their outstanding

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... c and volumetric capacities combined with solid cycle stability and high energy densities. Nevertheless, the demand for LIBs with higher energy densities and capacities is growing from year to year, urging research to look for alternative materials. Silicon has an outstanding theoretical capacity depending on the LixSiy phase, (i.e., 3579 or 4200 mAh.g-1), which is about ten times higher than graphite (372 mAh.g-1). The downside of silicon is that forming an alloy with Li leads to a substantial, irreversible specific and volumetric capacity loss, due to volume expansion (280-400 %) and solid electrolyte interface (SEI) formation during charge/discharge process. In this master's thesis project, studies on different protocols to synthesize mesoporous Si anode materials with enhanced cycle stability and specific charge values were conducted. Ordered mesoporous silicas (OMS) with different pore structures and particle sizes were used as starting materials for magnesiothermic reduction to silicon anode materials. Mesoporous silicon with high porosity and specific surface areas of 280 m2.g-1 (K1 made from KIT-6) were obtained. Unfortunately, heat accumulation appeared to be a serious problem, melting the ordered pore structures and original particle shape. Nevertheless, the average pore size of samples remained in the range of the starting materials (4-22 nm). An adapted reduction protocol including the use of NaCl as a heat modulator didn't decrease thermal effects and pore closing during reduction. The electrochemical performa [...]