Cottrell behavior

Such an it1/2 constancy is often termed Cottrell behavior. Deviations from such behavior occur at long times (usually over 100 s) as a result of natural convection... 

Recently, it was reported by Pyun et al. thatthe CTs of transition metal oxides such as Lii 8CoO2 [14,77-79], l i,, AiO. [11,12], Li, sMii.O [17,80,81], Lij + 8[Ti5/3Lii/3]O4 [11, 28], V2O5 [11, 55] and carbonaceous materials [18, 82-84] hardly exhibit a typical trend of diffusion-controlled lithium transport - that is, Cottrell behavior. Rather, it was found that the current-potential relationship would hold Ohm s law during the CT experiments, and it was suggested that lithium transport at the interface of electrode and electrolyte was mainly limited by internal cell resistance, and not by lithium diffusion in the bulk electrode. This concept is referred to as cell-impedance-controlled lithium transport. 

None of the CTs ever follow the Cottrell behavior - that is, there is no linear rela-... 

One can examine the current passed at the modified electrode during a potential step to the diffusion-limited regime for a solution species and then compare the result to the Cottrell behavior at a bare electrode (equation 5.2.11). Usually simple models, like those in Figure 14.5.1, are used. 

Non-Cottrell behavior throughout the lithium intercalation/deintercalation... 

Nahir, T.M. Buck, R.P. (1992) Modified Cottrell Behavior in Thin Layers Applied Voltage Steps under Diffusion Control for Constant-Resistance Systems. /, Electroanal. Chem. Vol.341, No.1-2, (December 1992), pp. 1-14, ISSN 1572-6657 Nair, P.R. Alam, M.A. (2010). Kinetic Response of Surfaces Defined by Finite Fractals. 

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