Persons

Recently, in the components of the lithium-ion accumulators (LIA) an anomalously diffusion behavior of ion transport has been discovered. Currently, the microscopic models LIA, consecutively taking into account sub- or superdiffusion and percolation of lithium ions into LIA, are unavailable. The semi-empirical LIA models, using the fractional-order impedances, based on the impedances of fractional order, which are substantiated by the anomalous diffusion of ions in a percolative disordered medium are becoming popular. In the work an assessment of the influence of anomalous diffusion on the impedance spectra within the framework of sub-diffusion generalization of the electrochemical model has been carried out. Using the subdivision equations with the time derivatives of fractional order, the LIA electrochemical model has been modified. Within the framework of this model, using the Fourier transform of fractional differential operators, an equivalent circuit, generalizing popular LIA circuit models has been derived. It has been shown that the slope of a rectilinear low-frequency part of the Nyquist diagram does not always unambiguously determine the subdivision coefficient α and can be both larger and smaller than the slope corresponding to normal diffusion. It has been stipulated that the degradations of the battery properties is associated with a change of the diffusion type in the LIA components.

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Unique properties of carbon nanotubes (CNTs) make them promising for creating composite electrode materials, based on the combination of CNTs with transition metals oxides. The influence of the RF plasma functionalization on vertically aligned carbon nanotubes arrays structural characteristics has been studied using the combinational scattering spectroscopy. At a higher partial argon consumption and low total gases expenditure the processing time pull with nickel oxide distribution, deposited by the SILAR method, upon the nanotubes has been determined. By means of the scanning electron microscopy it has been shown that an increase of the functionalization time from 30 to 1200 seconds permits to increase the depth of CNT surface coverage by the nickel oxide layer from 300 nm to 2.5 μm. The resultant composite structures can be used as a supercapacitor electrode.

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The analysis of the current and future developments in the field of the power elements based on the ß-decay has been executed. The possible technologies of creation have been described and the calculations of the efficiency for produced by them power sources have been presented. The possibility of creating a self-charging supercapacitor based on CNTs using isotope Ni63 and C14 has been examined. The theoretical calculation, confirming the perspectives of selecting the fields of investigations, has been performed.

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