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This paper describes active mass and collector resistivity and impedance changes of lead-acid accumulator electrodes. Data was obtained during experiment with pulse charging cycling of old lead-acid accumulator. Resistivity changes of active mass and collector were measured using four-point direct current method. Impedance changes were observed by electrochemical impedance spectroscopy. Old lead-acid accumulator previously not used for almost half of a year was used in the experiment. Reasons why pulse charging was used follows: increased efficiency of charging, gas generation reduction, corrosion speed reduction, sulfation reversion of old cells.

This paper deals with measurement of negative electrodes with different additives in electrode active mass. The main aim of experiment was to find out if additives will have significant effect to imaginary part of impedance. Three electrodes were compared. The first electrode (nr.2) had titan dioxide additive, the second electrode (nr.3) had nano-size titan dioxide additive and the third electrode (nr.5) had the carbon type CR2996 additive. ExperimentalMeasurement method used was slightly modified electrochemical impedance spectroscopy. New method evolved from older one developed at our department of electrotechnology twenty years ago. This method required us to create our own electrodes with non-continuous system of parallel ribs, because to each rib two (voltage and current) wires are connected. So we can select ribs of electrode we wanted to measure (1,2).As it was told above, experimental electrodes with system of non-continuous parallel ribs (Fig. 1) were used. Ribs were fixed by epoxy resin. To each rib one voltage and one current wire were connected.Equivalent diagram of experimental electrode is at fig. 2. Rp means wire resistance that was measured before the experiment begins, Zk means corrosion impedance of interphase electrode/electrolyte, Zm means impedance of active mass. Measurement procedure is similar as one used in our experiments published lately. Measurement is composed of two steps, frequency dependency is measured between ribs 2-3. During first step current flows between ribs 1-4 and in second step the current flows between ribs 2-4. In first step we theoretically measure impedance of active mass Zm and

Because the preadolescent's inner world is still undeveloped and insufficiently enriched by the experience of experiencing critical situations that stand in the way of meeting important needs, his activism, aimed at overcoming them, is not stimulated. Therefore, in difficult situations the preadolescent includes the defense mechanisms. When the mechanisms prove to be inefficient, the body instinctively looks for a way out and often finds it in the external environment. Psychoactive substances can be used as external procedures to defend against the psychotraumatic situation and the vulnerability of preadolescents to drug use is directly related to the fact that drugs have become accessible, the consumption being often associated with the pressure exerted by the group of friends.

Following article deals with thermal phenomena in lead acid batteries. Possitive influance of negative active mass materials was tested on experimental electrodes, also different separators were used.