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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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The experimental data of the submicron periodic structures that are due to the laser radiation in air in a liquid medium (distilled water) on the surface of the polycrystalline nickel formed have been presented. By the electron microscopy methods the geometry of the formed surface structures has been defined: under irradiation in the air the structure is formed above the sample main surface, and under irradiation in liquid - below. The size of the pure nickel nanoparticles, produced by laser ablation formed by laser ablation of the nickel sample in liquid, has been measured.
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In development of radio isotope electric feed sources of long-term service for various application in the space branch, medicine, nano-and microsystem equipment, cryptography and telecommunications one of the most important issue is the determination of their reliable operation temperature range. In the work the influence of the negative and positive temperatures in the range from -60 to +60 °C to the output parameters of radio isotope sources of electrical feed, based on the energy double conversion has been investigated. It has been shown that in the indicated temperature ranges the voltage of the radio isotope idle running is 4 times increased. In this case the maximum value of the returned power loading is realized at temperature near 0 °C.The influence of temperature on all stages of the energy conversion has been analyzed. The investigations demonstrate that a significant reduction of the idle running and the shape of the returned power curve are determined by two mechanisms: a decrease in the luminous intensity of radioluminescent light sources (temperature quenching of lumninescence emission) and a decrease in the efficiency of the photoconverters. In this case, the decrease in the efficiency of photoconverters is weakly expressed in the negative temperature range (from -60 to 0 °C), and the main contribution, to the change of the output parametrers of the power sources is made by the thermal quenching of luminescence in the light source. In the positive temperature range both processes have a significant effect on the reduction of the output voltage and power.
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The radioisotope power sources based on the principle of the tritium beta-radiation power conversion sequentially into light and electric energy have been investigated. The spectral characteristics of used radio luminescent light sources, the spectral and electric characteristics of semiconductor photo converters have been analyzed. The experimental nuclear battery cells have been developed, based on which the battery with the short circuit current values U = 2.5V and I=1.2 µA at no-load voltage, respectively, has been assembled. The battery can be used as a power source for used household electronic devices with low power consumption.
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