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Negative lead electrode for hybrid electric vehicles
Opravil, Petr ; Zimáková, Jana (referee) ; Bača, Petr (advisor)
This bachelors thesis is focusing on degradational proceses occurring in electrodes of lead-acid batteries working in parcial state of charge used in hybrid electric vehicles. Studied topics include storage of electrical energy, hybrid powertrains and lead-acid accumulators. Experimental cells have been made and were later used in experiments maintaining partial state of charge. This work is focused on finding a link between silanized glass fibres added to the electrodes and lowering the amount of degradation of cells.
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Optimalization and methods of internal resistance measurement of the lead acid battery cell
Fojtlín, Branislav ; Vaculík, Sebastian (referee) ; Křivík, Petr (advisor)
The aim of this master´s thesis is optimalization and methods of measuring the internal resistance of lead acid accumulator. First focus is on the analysis of properties of lead acid accumulators, their construction and negative effects. After that a method of measuring the internal resistance of experimental accumulator is processed. In this thesis practical design of measuring workplace is completed. The frequency analysis of impedance of charging and discharging accumulator is performed. After that the graph of internal resistance for various amplitude intensities, for various signal forms and also for various size of frequencies of alternating current are processed. The result of this thesis is a comparison of graphic works addictions charging and discharging characteristics of lead acid accumulator and determination of optimal amplitude, form and intensity of frequency of alternating current in point when internal resistance is evaluated correctly.
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Oxygen cycle during pulse charging of lead-acid accumulator
Havlíček, Jiří ; Vaněk, Jiří (referee) ; Křivík, Petr (advisor)
This master´s thesis applies to puls charging of lead-acid accumulator and arising oxygen cycle while charging. First part of the thesis is focused on potential dividing of lead-acid accumulators and their construction. I also focus on priciples of submerged electrodes accumulator, gel accumulator and AGM accumulator based on oxygen cycle. The next topic are thermal and degradation processes inside accumulators and their influence on capacity and lifespan. In theoretical part am I describing ways of charging and I also point out possitives and negatives. Practical part focuses on producing experimental cell and its form. Experimental cell is tested to different modes. I evaluate their influence on temperature inside the cell, intensity of oxygen cycle and capacity. I compare their influence on duration of charging cycle to another possible charging modes.
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Effect of glass fibers in the lead-acid batteries for hybrid electric vehicles
Klojda, Viktor ; Tošer, Pavel (referee) ; Bača, Petr (advisor)
Master´s thesis deals with the utilization of lead-acid accumulators in hybrid electric vehicle regime. It describes the side effects known as PCL, generated during PSOC regime and connected with the length of the battery lifespan. One possibility how to eliminate these effects, is the use of additives in active mass of the negative electrode, in the form of glass fibres. The project provides the parametres and reactions of additive, that have lead to the improvement of battery properties. The purpose of this thesis is to verify the positive effect of the aditive on the lifespan of the lead-acid accumulator.
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Development control programme for autonomous fotovoltaic system
Janáč, Stanislav ; Vaněk, Jiří (referee) ; Bača, Petr (advisor)
The project considers realization system, which allows us to test six different operation modes on lifetime of accumulators. The system will be connected to computer, that will perform measurement of current and voltage and switch betwen charge and discharge modes. The measured values will be recorded in certain time intervals to computer memory. After some time these measured data will be analised and the most optimal operational mode will be set.
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Impedance Measurement of Lead-acid Accumulator
Abraham, Pavel ; Dostál, Zdeněk (referee) ; Jareš, Petr (referee) ; Bača, Petr (advisor)
This dissertation deals with impedance measurements of lead-acid accumulator. Main aim was to study recent problems of impedance measurements of lead-acid accumulator and most importantly to extend difference method and also to interpret its results. The original DC difference method was developed earlier at our Power Sources Laboratory of Department of Electrical and Electronic Technology. The DC difference method and also the new AC difference method are both non-destructive, which means that experimental data can be obtained in situ. New method provides more accurate set of information because of its wide frequency range nature. Electrodes of lead-acid accumulator were analysed with special attention to collector / active mass double layer and to active mass itself. Various states and operation regimes were investigated. Obtained data contributed to better understanding of involved degradation mechanisms. Main aim of other experiment was to observe and interpret corrosion rates of electrode collector composed of various lead alloys. Last but not least charge and discharge regimes e.g. 100% deep of discharge regime, partial state of charge (PSoC) regime and pulse charge regime were analysed. BioLogic VSP was the device used for almost all experimental measurements. It takes a lot of effort to optimise VSP operation regime. Best operation regime of VSP for the difference method was suggested too.
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