Dresden 2020 – wissenschaftliches Programm
Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...
CPP 89.2: Vortrag
Donnerstag, 19. März 2020, 09:50–10:10, HSZ 301
Evaluation of the Applicability of the Brick Layer Model for Describing the Electrical Transport within Ceramic Materials — •Janis K. Eckhardt1,2, Markus S. Friedrich2,3, Matthias T. Elm2,3,4, Peter J. Klar2,3, and Christian Heiliger1,2 — 1Institute for Theoretical Physics, Heinrich-Buff-Ring 16, 35392 Gießen, Germany — 2Center for Materials Research (LaMa), Heinrich-Buff-Ring 16, 35392 Gießen, Germany — 3Institute of Experimental Physics I, Heinrich-Buff-Ring 16, 35392 Gießen, Germany — 4Institute of Physical Chemistry, Heinrich-Buff-Ring 17, 35392 Gießen, Germany
In literature, the transport properties of ceramics such as the active cathode material within lithium ion batteries are commonly described by making use of the so called Brick Layer Model (BLM). The BLM cannot account for percolation effects. However, the microstructure of real devices, e.g. secondary materials of cathodes or thin films is such that disorder will lead to percolation effects. In order to account for these effects and to validate the applicability of the BLM an impedance network model based on Kirchhoff’s current law has been developed. With its help it is possible to compute impedance spectra and current density distributions of defined or random structures that mimic the properties of the real microstructure. Comparing the computational result to the prediction of the BLM, it becomes obvious that an additional semicircle(s) and signal(s) respectively in the impedance and distribution of relaxation times spectra may occur. This effect can be attributed to the multidimensional transport mechanism within the structures which is not accounted for in the commonly used BLM.