Numerical models for ionic conduction in CuBr-TiO2 composites and for electrolysis of CuBr films

The influence of size dispersion of CuBr grains on the experimentally observed conductivity enhancement in CuBr-TiO₂ composites is investigated. Using an extension of a random resistor network model recently introduced, we show that a bimodal size distribution can be simulated using a mean size value. Furthermore, we develop an electric breakdown model to simulate dendritic decomposition structures observed near the copper electrodes when a certain voltage is applied to thin CuBr films. Preliminary results for homogeneous systems without conductivity gradient are presented. Paper presented at the 6th Euroconference on Solid State Ionics, Cetraro, Calabria, Italy, Sept. 12–19, 1999.