Portable and Highly Versatile Impedance Meter for Very Low Frequency Measurements

Abstract

Electrical Impedance Spectroscopy (EIS) is a characterization technique that is gaining more and more importance in various fields of research and applications. The frequency range of investigation varies according to the type of application. In some fields (biology, medicine, energy) it is useful to be able to perform measurements at very low frequency values (down to a few mHz or even below). While impedance meters operating at frequencies in the range from a few tens of Hz up to a few MHz can be regarded as quite standard pieces of instrumentation commonly available in many laboratories, instrumentation for measurements at very low frequencies, although commercially available, is less common. The subject of this work is the design, realization and testing of a low frequency impedance measurement platform that has the advantage of being portable, rather inexpensive, and yet highly versatile. In our approach, we exploit a personal computer and a soundboard as a powerful system for digital signal generation and analysis that, with the help of low complexity and low-cost external hardware and a public domain software for the implementation of the core system, allow to tailor the platform for targeting specific applications with minimal effort. As an example, we will demonstrate the application of the system to the investigation of polypyrrole-based supercapacitor structures.

Polypyrrole and Graphene Nanoplatelets Inks as Electrodes for Flexible Solid-State Supercapacitor

“…The values of the areal capacitance of the cells using electrodes developed from the PPy-GNP inks compare well with those obtained elsewhere using polyrrole and graphene based electrodes [39,40]. Impedance measurements were also performed on the test capacitors using the dedicated instrumentation discussed in [41]. In particular, we explored a very low frequency range, which was as low as 10 mHz with a 0 DC bias and a 20 mV amplitude for the AC test signals.…”

“…Impedance measurements were also performed on the test capacitors using the dedicated instrumentation discussed in [41]. In particular, we explored a very low frequency range, which was as low as 10 mHz with a 0 DC bias and a 20 mV amplitude for the AC test signals.…”

Impedance Spectroscopy and Its Application in Measurement and Sensor Technology

“…Especially for the measurement of impedance spectra at very-low-frequency values down to a few mHz or even below, many challenges should be solved. In this context, Scandurra et al [1] address the design, realization, and testing of a low-frequency impedance measurement platform. The realized system is portable, low-cost, and highly versatile.…”

Development of a Simple Setup to Measure Shielding Effectiveness at Microwave Frequencies

“…Although most of the electromagnetic emissions were intentional and beneficial for society, the coexistence of such a huge number of electromagnetic sources resulted in the onset of electromagnetic interferences (EMIs), which should be carefully considered in order to avoid electromagnetic compatibility (EMC) issues where EMIs interfere with the proper operation of other electronic devices [ 4 , 5 ]. The scientific community has always been prudent concerning the possible effects on human health; several examples have seen the possible effects of EMIs on test equipment, both at low and high frequencies, and for various applications from the biomedical to the industrial field [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ].…”