Solid State Ionics, Vol.147, No.3-4, 249-257, 2002
Polymer electrolytes and polyelectrolytes: Monte Carlo simulations of thermal effects on conduction
Monte Carlo calculations were carried out to simulate ion diffusion through polymer matrices. A dynamic bond percolation (DBP) model was employed that includes local harmonic motion of covalently bound anions in polyelectrolyte systems. The temperature dependence of cation diffusion was investigated in polyelectrolytes and polymer-salt complexes for 0-100 degreesC. Systems in which the rate of polymer reorganization is independent of temperature display Arrhenius behavior both above and below the T-g of 35 degreesC. Systems in which the temperature is coupled to the rate of polymer reorganization display VTF behavior above the T-g and near Arrhenius behavior below the T-g. In all cases. the temperature is coupled to the rate of successful ion jumps. Temperature and T-g seem to have no effect on the ion density at which the cation conductivity reaches a maximum.
Keywords:polymer electrolyte;polyelectrolyte;ion conductivity;temperature dependence;Monte Carlo simulations;dynamic bond percolation model