In this thesis the behavior and properties of solid-state batteries based on multiple electrodes are analysed. For this purpose thin film systems of the relevant materials are prepared to achieve model system for more detailed analysis of the material specific properties. The characterisation of the systems is carried out with typical physical and electrochemical methods and especially using impedance spectroscopy.The first material analysed in this thesis is Li4Ti5O12 which was recognized early on as an interesting candidate for an anode material for solid-state batteries due to its miniscule volume expansion during lithium insertion and extraction. For this material the preparation of thin film systems and the optimisation of preparation parameter is shown and special properties of the material in the system are discussed. Lithium titanate shows a clear two-phase behavior and the properties of the charged and discharged phase are vastly different. The main difference here is the ionic and electronic conductivity. The properties of the two phases are evaluated using impedance spectroscopy and conclusions about the phase transition are drawn from this data. The main point of discussion is between a phase transition based on a two-phase system or a solid solution system. Aside from the phase transition other properties of the system like the interaction between electrode and electrolyte are explained. It is shown that the resistance between electrode and electrolyte is miniscule but an additional electronic charge transfer between electrode and substrate material can form under certain circumstances. This phenomenon occurs due to the semiconducting, almost insulating nature of lithium titanate, which leads to extended space charge layers in the material. These space charge layers can also appear in contact with metal substrates and can hinder the cell performance for very thin electrode layers.In the second part of the thesis similar experiments are performed on another electrode material using lithium nickel manganese oxide. This material is of interest as cathode material due to its high working potential versus lithium metal. The work is mostly focused on the problems in electrode preparation, especially film adhesion, and evaluation of the interface between cathode and electrolyte. The data is interpreted in comparison to the data of lithium titanate and differences and similarities are highlighted. Additional the question of which phase of the material is deposited is exploded and how the interface between cathode and electrolyte changes in dependence of the utilized deposition method.
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