импеданс

The electrochemical characteristics of the negative electrodes of the lead-acid battery with additives of carbon nanotubes and graphene were studied. It was shown that the highest values of the capacitive characteristics of the electrodes were obtained by adding carbon nanotubes to the negative active mass. The processes occurring on the negative electrode were studied by the method of impedance spectroscopy. Applying simulation, an equivalent electrical circuit was obtained, which adequately approximated the obtained frequency dependences.

The new materials obtained in the potassium polytitanate (PPT)–MnSO₄ system by modifying PPT in aqueous solutions of manganese sulfate of various concentrations, followed by thermal treatment and annealing at 1080°C, were synthesized and studied. The phase composition of the obtained materials was determined. Their electrochemical and electrophysical properties in the temperature range from 250 to 700°C were studied.

The electrochemical and electrophysical properties of the protonated and modified with silver iodide potassium titanates, which can be applied in energy storage units, have been investigated by impedance spectroscopy. It has been shown that the dielectric losses at medium and high frequencies are weakly dependent on the polarizing voltage. It has also been established that transfer in modified potassium titanate can be made through potassium and silver ions.

We have studied the capacitance and kinetic properties of nanoporous carbon material which was obtained from wood. The maximum radius pore distribution of the investigated material was 1.37 nm. The data from X-ray scattering and electrochemical impedance spectroscopy was used to investigate the influence of porous structure change and electronic structure of activated carbon material on the mechanism and kinetics of charge-discharge at 7.6m KOH solution.

Work is devoted to the study of electrochemical and dielectric properties of the base potassium polytitanate and polymer composite based on it. The temperature dependence of ac-conductivity, permittivity, dielectric loss tangent. An increase in the dielectric constant of the composite with respect to the values of the dielectric constant of the base potassium polytitanate. The values of the dc-conductivity.

The work is devoted to investigation of the anisotropy of conductivity and determination of the most likely charge carriers in the amorphous polytitanate potassium. Defined ac – and dc-conductivity, dielectric permittivity, dielectric loss tangent in mutually perpendicular directions compacted potassium polytitanate.
An increase in the shift of the peak and the dielectric loss tangent in a frequency region when measured along the preferred direction location lamellae potassium polytitanate.

A various features of the electrochemical behavior of number superfine carbon materials in electrolyte based on an ionic liquid 1-methyl-3-butilimidazolium tetrafluorineborate (1Me3BuImBF4) were determined by voltammetry and impedance methods. A comparative analysis of the effect of the type and nature of the electrolyte material on the main electrochemical characteristics of carbon electrodes which may be used in supercapacitors was done.

DOI: https://doi.org/10.18500/1608-4039-2017-17-4-225-234

The electrochemical characteristics of electrodes based on various fibrous carbon materials (manufactured by OOO NPTs Uvikom) for hybrid supercapacitors C/PbO₂ with an acid electrolyte have been investigated. It is shown that the highest values of the capacitive characteristics of the electrodes were obtained using carbon activated felt UVIS-AK-V-170, characterized by capacities up to 400 F/g.

In this paper, the electrochemical and electrophysical properties of protonated potassium polytitanate synthesized at pH values varying from 3.11 to 8.88 depending on the magnitude of the polarization voltage and the magnitude of the measured signal were studied by the method of impedance spectroscopy. The values of effective conductivity, relaxation times, frequency dependences of the loss tangent, and dielectric permittivity are determined.