Polyaniline is deposited potentiodynamically on a nickel substrate in the presence of p-toluene sulfonic acid and the specific capacitance is estimated. The electrochemical characterisation of the electrode is carried out by means of cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge-discharge experiments. The specific capacitance is similar to 4.05 x 10(2) F g(-1). This indicates the feasibility of the polyaniline-coated nickel electrode for use in electrochemical supercapacitors. (c) 2005 Elsevier B.V. All rights reserved.