Due to their potentially higher energy and power density, lower influence of the ambient temperature (freezing of liquid electrolyte) and higher safety compared to liquid electrolyte based lithium ion batteries, solid electrolyte based lithium batteries are gaining more and more interest. A variety of anode concepts, solid electrolytes and cathode concepts have been developed. All battery characteristics, such as energy and power density, cycle stability, but also the chemical stability between the materials can be influenced by a wide variety of combinations. Additionally, it may be necessary to use further additives or protection concepts.The first goal of this dissertation was to make a comprehensive comparison of the current literature and to put it into context with own battery data as a reference. This was necessary because results are sometimes not classified in the existing literature, no reference is added or no consistent data on masses and manufacturing methods are given. With this first work it was possible to draw in-depth conclusions about the minimal information needed for reproduction, but also to make recommendations for future research goals. Furthermore, an application for the calculation of battery performance was designed, where the calculations are based on minimal information. In the evaluation of the literature it was found that in the majority of publications carbon additives are used in the cathode composites. In the second publication, the focus was on the optimization of battery performance using carbon additives and the influence of their carbon morphology and surface. Cycling experiments and microstructure-resolved simulations show that with fibrous carbons a higher utilization of the cathode active material can be achieved. However, carbon additives lead to an increased capacity loss due to the decomposition of the solid electrolyte. The latter was investigated in more detail by means of cyclovoltammetry, X-ray photoelectron spectroscopy and cyclization experiments. The degree of degradation is directly related to the carbon morphology and surface. To prevent the reactions caused by the use of carbon additives, a protective concept was developed and tested.The results of this dissertation form the context for a comprehensive comparison of different cell concepts. The basic parameters are presented and discussed. Thus, the current state of the art in the field of solid-state batteries is summarized and evaluated. Recommendations and goals for a successful further development of solid-state batteries can be derived from this thesis. In the second part of the thesis such an optimization was carried out. The positive influence of carbon additives was examined more closely and the existing decomposition was reduced by a novel protection concept.
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