Study of the electrochemical behaviour of electrodes in solid state supercapacitors

In this work the electrochemical behavior of anodes and cathodes of small size full solid-state supercapacitors which operated in continuous cycling tests has been investigated. The electrochemical measurements were carried out in a cell equipped with a reference electrode (r.e.). Two types of supercapacitors were studied, the first one, a symmetric supercapacitor, based on activated carbon materials in the electrodes and the other one, a hybrid supercapacitor, based on activated carbon materials and ruthenium oxide. The introduction in the cell of the r.e. allowed to follow the voltage changes at the anode and at the cathode during the cyclic voltammetry (CV) and the galvanostatic charge-discharge (CD) measurements. The evaluation of the influence of some parameters of the electrodes on the performance of the complete supercapacitor has been investigated in this work. We would demonstrate the utility of this method of investigation in the study of the behavior of both electrodes and of supercapacitors. As an example of study we report the influence of the amount of activated carbon or of the presence of ruthenium oxide in the electrodes on the electrochemical performances. In detail, it has been investigated the influence of amount of active carbon materials on behaviour of the anode and cathode and of the full supercapacitors during charge and discharge processes at different conditions of voltage sweep rates (CV tests) and currents (CD tests).