Test & Measurement

Abstract:

Low frequency noise is a well-known tool for quality and reliability assessment of electronic devices. This phenomenon is observed in different electrochemical devices as well (e.g., smart windows, electrochemical corrosion processes). Thus, we can assume that the same tool can be used to asses quality of supercapacitors.

Their quality is usually determined only by capacitance and/or equivalent series resistance (ESR), or impedance. Degradation of supercapacitors’ is indicated by a change of capacitance and ESR and is measured by the established methods, determined by industrial standards. We propose to extend these methods by using low frequency noise measurements which should be in our opinion more sensitive to any changes degrading supercapacitors’ structures. This task is quite difficult because capacitance of the tested specimen is at least about a few or even a few dozens of Farads. It means that we can measure 1/f noise at very low frequency range only. This method is a new one and should be helpful in developing more advanced and economically efficient supercapacitors.

We discuss requirements for the measurement set-up and its possible configurations. Next, the prepared measurement set-up consisting of current/voltage sources, a switching unit, a data acquisition board and a computer controlling the process is described. Some experimental noise measurements are presented as well.

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