Simplified methods for determining the ionic resistance in a porous electrode using linear voltammetry

Two simplified methods are proposed for determining the internal ionic resistance of a porous electrode using linear voltammetry in the double layer region. With the 70% current response time t(0.7) on linear voltammogram and the independently measured uncompensated solution resistance R-e, the internal ionic resistance of a porous electrode can be calculated using the equation R-p=2.483t(0.7)/C-total-2.989R(e), where C-total is the total capacitance of the porous electrode and can be deduced from the plateau current on the voltammogram. When R-p is not much smaller than R-e, it is also possible to estimate the ionic resistance according to the curve shape of the linear voltammogram without knowing R-e. (C) 2001 Elsevier Science B.V. All rights reserved.