Interfaces and Interphases in Rechargeable Li Based Batteries: Cathode/Solid Electrolyte - Impedanzanalyse und Tomographie

At KIT, IAM-ET solid electrolytes and cathode / solid electrolyte interfaces developed by our partners will be analyzed by means of electrochemical impedance spectroscopy and tomography. The experimental investigations will provide a correlation between processing, microstructure and electrochemistry of the samples. The results will contribute to the development of materials and interfaces and support modeling and model validation.

At IAM-ET solid electrolytes and their interfaces will be analyzed electrochemically, aiming at a correlation of microstructural and electrical properties. To quantify the resistivity contributions of grains, grain boundaries and secondary phases impedance spectra will be measured in the frequency range from 100 Hz up to 3 GHz and evaluated by means of the distribution of relaxation times. WP 2 is about different types of cathode / solid electrolyte – interfaces, planar model interfaces as well as 3D structured ones will be investigated. To analyze their electrochemical properties cells with a low impedance counter electrode will be set up and tested. Impedance spectroscopy and the distribution of relaxation times for impedance analysis will be applied to set up appropriate equivalent circuit models. Combining electrochemical results and microstructural parameters, which will be gathered from 3D-reconstructions (FIB-SEM and µCT) of the electrodes, a quantification of the different loss mechanisms will be enabled. The experimental results will be continuously provided to the partners to support the development of models, materials and processes.