импедансная спектроскопия

DOI: https://doi.org/10.18500/1608-4039-2018-18-3-122-127

Impedance spectroscopy was used to study the initial stages of lithium anode dissolution in SAFT LS-33600 cells at frequencies more than 35 Hz. It was found that experimental results can be described by the dissolution of metals covered by a passive film, including the stages of film dilatation and breakdown of the film.

The effect of 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF4) and 1-butyl-3-methylimidazolium tetrafluoroborate (BMIBF4) ionic liquids on the properties of the polymer electrolyte based on polyethylene glycol diacrylate (PEG-DA) and LiBF4 salt was studied. Research was carried out by spray-mass spectroscopy, differential scanning calorimetry, and electrochemical impedance spectroscopy technique in the temperature range from -40 to 120 °C.

Conductivity of yttria stabilized zirconia (YSZ) produced from weakly agglomerated nanopowder investigated by ac impedance spectroscopy. Dense ceramic samples with grain size from 90 to 800 nm were made by variation of both pressing and sintering conditions. It is found that the bulk conductivity is independent of grain size, but grain boundary conductivity is depended. Observed grain boundary resistance increases with grain size. It is in contradiction with previous results observed for range 1–18 μm where grain boundary resistance decreases with grain size. As result the maximum of grain boundary resistance vs ceramic grain size it seems is observed.

The possibility of the use of impedance spectroscopy using an impulse method of step current change and recording voltage change in during time at the terminals of a cell with subsequent Fourier transform of the input signal and the response to it to assess the current state of Li-cell. It is proposed use of current pre-impulse in order to minimize the influence of passive film. It is substantiated an algorithm based on the measurements of impedance phase for determining of residual capacity.

The Work is devoted to the research of influence of superficial processings of bipolar plates (BP) on specific electric characteristics of fuel ce)(s (FC). Researches were conducted on plates on the basis of the titan. Two methods of processing BP are considered: electrochemical gilding and ionic implantation of carbon. In work short descriptions of the resulted technologies, and also a technique and results of experiments are presented. In work it is shown that as gilding, and ionic implantation carbon titanic BP electric characteristics FC improve. Relative reduction of ohmic resistance FC in comparison with "pure" titanic plates have constituted 1,8 for electrochemical gilding and 1,4 for ionic implantation.