Electrode polarization in dielectric measurements: a review

Abstract

In this review, we present an overview of the state of the art concerning the fundamental properties of electrode polarization (EP) of interest in the measurement of high conductivity samples and its implications for both dielectric (DS) and impedance spectroscopy (IS). Initially a detailed description of what constitutes EP is provided and the problems that it induces. Then, we review some of the more popular models that have been used to describe the physical phenomena behind the formation of the ionic double layer. Following this we shall enumerate the common strategies used historically to correct its influence on the measured signals in DS or in IS. Finally we also review recent attempts to employ fractal electrodes to bypass the effects of EP and to offer some physical explanation as to the limitations of their use.

Mechanical, dielectric, and physicochemical properties of impregnating resin based on unsaturated polyesterimides

“…This leads to a separation of positive and negative charges, which give rise to an additional polarization. The increase in temperature makes it possible for the ionic charges to move from the bulk to the interface between the electrodes and the insulator [21,22]. One can observe a slight decrease in permittivity from 160°C for the same isofrequency spectrum of 0.1 Hz.…”

Electrical Impedance Spectroscopy for Quality Assessment of Meat and Fish: A Review on Basic Principles, Measurement Methods, and Recent Advances

“…Thus the most fundamental measuring method is using two electrodes to induce the current ( ) and to measure the voltage ( ). However, in this bipolar measurement method, because of the existence of electrode polarization, the measured impedance consists of two parts, that is, impedance of measured object and parasitic capacitive impedance on the interface of the electrode-sample ohmic contacts [22,56]. The parasitic impedance decreases with frequency increasing; thus it can be ignored when frequency is high in bipolar measurement system [17].…”

“…Electrode distance variation technique can be used for electrode polarization correction in bipolar measurement system. Some researches thought that capacitive gap contact between electrode and sample reflected the feature of the samples [22,56]. Based on electrode distance variation technique, Damez et al [61] investigated contact impedance as a parameter of interest for assessment of meat ageing.…”

“…Limitation of the technique is that the polarization impedance becomes large in comparison with the sample impedances at low frequencies. Therefore, the spacing between electrodes should be as large as possible in order to increase the weight of the sample impedance [56].…”

Epoxy/BN micro- and submicro-composites: dielectric and thermal properties of enhanced materials for high voltage insulation systems

“…An additional phenomenon has been observed at high temperatures and low frequencies for neat epoxy and all BN composites likewise, the so-called electrode polarization (EP). This is a parasitic phenomenon well known for epoxy resin and its composites [12][13][14], which can be related to a delay in charge transfer at interfaces between sample and electrodes, giving rise to additional interfacial polarization on a macroscopic level. This peak due to EP at high temperatures and low frequencies is overshadowed by low-frequency dispersion due to charge fluctuation, possibly superimposed by electronic conductivity, which is a rather common behavior for solid insulating materials at elevated temperatures.…”