Charge transport diffusion coefficients temperature dependence

A full model of the charge transport in the electrolyte would require the detailed description of the ionic transport processes inside the electrolyte. However, for the orientating study pursued in this contribution, it seems more appropriate to choose a simpler model that is able to describe the temperature dependence of the electrolyte qualitatively. The temperature dependence of diffusion coefficients in molten electrolytes can be described by an Arrhenius function [1]. Therefore, the temperature dependence of the conductivity is assumed to be of an Arrhenius type, as suggested in [6]. 

As explained before, the open-circuit potential of the battery depends on concentration, temperature, and transport limitations. The real voltage delivered by a battery in a closed circuit is affected by ohmic limitations (ohmic potential), concentration limitations (concentration overpotential), and surface limitations (surface overpotential). The close circuit potential of the cell is given by the open-circuit potential of the cell minus the drop in potential due to ohmic potential, concentration overpotential, and surface overpotential. The ohmic potential is due to the ohmic potential drop in the solution. It is mostly affected by the applied charge/discharge current of the battery. The concentration overpotential is associated with the concentration variations in the solution near the electrodes. It is strongly affected by transport properties such as electrolyte conductivity, transference number, and diffusion coefficients. Finally, the surface overpotential is due to the limited rates of the electrode reactions. 

In which the first term corresponds to the charge of the interface, the second term expresses the temperature dependency of the diffusion coefficient and YC is the TEC mass transport transfer function. According to the theory developed by Aaboubi et al. (Aaboubi, Citti,... 

Low values for the positive and negative charge carrier mobility have been reported for solid helium (Dahm, 1986). The dependence of the mobilities on temperature is thermally activated (see Figure 7). Increase of external pressure reduces the mobilities. These experimental facts indicate that an ionic-type transport occurs in this solid. The diffusion coefficients, D , of the carriers follow Equation 111 in... 

Transport of molecules across the cell membrane occurs by passive and facilitated diffusion and active transport (Stein, 1986 Finkelstein, 1987). Passive transport is governed by a mass-transfer coefficient, surface area for exchange, transmembrane concentration difference, and a partition coefficient. The partition coefficient can be modified by charge, pH, temperature, and presence of other drugs. Facilitated transport may be most simply described by Michaelis-Menten kinetics. Depending upon the carrier system, symmetric or asymmetric models may be used. 

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