impedance

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.

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.

The paper considers the electrochemical properties of potassium polytitanate synthesized at the values of pH varying from 3 to 8 in a wide temperature range from  − 26 to  + 80°C. The conductivity values and the activation energy were determined with the help of the method of impedance spectroscopy. The application of the obtained material used as a ceramic solid electrolyte in the energy storage units operating at low temperatures in the Far North is considered in the article.

Electrochemical characteristics of electrodes based on various carbon materials such as expanded graphite, nanotubes, black carbon for hybrid supercapacitors C/PbO₂ with acid electrolyte were investigated. It was shown that the highest values of the capacitive characteristics were obtained using TUBALL graphene nanotubes (LLC OCSiAl.ru, Novosibirsk).

The work is devoted to the study of the electrochemical characteristics of prototype energy storage devices made on the basis of electrodes consisting of titanium-modified graphite woven material “busofit”. It is shown that the modification increases the specific values of the capacitance and the magnitude of the operating voltage.

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

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.

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.

In this paper, we investigated the possibility of determining the internal resistance of the battery by pulsed method with followed Fourier transformation in transition characteristics. The changes of internal resistance of lithium sulfur cells were studied in dependence on the discharge and charge depths during continuous cycling by proposed method. It was shown that the internal resistance of lithium sulfur cell was maximal at the point corresponding to the transition between high-voltage and low-voltage plateaus both at the charge curves and at the discharge curves. The most significant increase in the internal resistance of lithium sulfur cells occurs at the initial stages of cycling. It was found that the internal resistance of lithium sulphur cell is governed by the way the state of charge is achieved. This is due to the difference in densities of products, generated in positive electrodes by electrochemical reactions at charge (ρ(S) = 2.07 g/cm³) and discharge (ρ(Li₂S) = 1.63 g/cm³).