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Investigation pressure effect on lead-acid accumulator lifetime for hybrid electric vehicles.
Kulhány, Andrej ; Bilko, Radek (referee) ; Bača, Petr (advisor)
The thesis is focused on remitting lead-acid segments of partial charge mode which simulates the conditions in HEV. The experimental cells were submitted to different pressures on the electrode system. The main aim of the thesis was to minimize the irreversible sulphating of the negative electrodes, which are in the PSoC regime limiting in the overall life of lead-acid accumulators. All cells were submitted to measurement of the negative electrode potentials, resistance of active materials, contact resistance of the grid – the active material and measurements of pressure changes during three PSoC cycles.
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Monitoring the condition of a lead-acid battery used in automobiles
Folk, Jan ; Zimáková, Jana (referee) ; Binar, Tomáš (advisor)
The aim of this bachelor thesis is to test the properties of lead-acid batteries according to the ČSN standard. The work deals with test methods on a lead-acid battery, which examines the life test, charging current test and reverse capacity test. Furthermore, the work deals with the thermal loading of the lead-acid battery under extreme conditions that may occur during transport. The lead-acid battery transport will be simulated using the Solidworks modelling program and the Ansys simulation program.
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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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Lead-acid battery charger with a pulse converter
Mihályi, Róbert ; Martiš, Jan (referee) ; Vorel, Pavel (advisor)
This master´s thesis discusses on complete designing of a lead-acid accumulator charger. Charger operates with the principle of a two-switch forward converter. It contains the design and manufacturing of all the proposed winding subcomponents, the semiconductor components, the control circuit board and the power circuit board. This thesis includes also the design and description of the individual parts of the power circuit and control circuit. The revival of the charger, including a description of the individual adjustments that were necessary for proper and reliable operation is also in the content. This thesis contains too a series of measurement performed to verify the correct function of the charger.
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Impedance measurement of lead-acid accumulator properties
Vaculík, Sebastian ; Neoral, Jiří (referee) ; Abraham, Pavel (advisor)
This work deals with the new and unique four-point method measurement of the impedance characteristics for experimental positive electrode. The theoretical part provides a short introduction to the electrochemical power sources, including the lead-acid batteries, which were used for measurement. Furthermore, there is description of the principle of electrochemical impedance spectroscopy and analysis of obtained data by using the equivalent circuit, consisting of passive components. The experimental section is devoted to the description of the device, which is used for realization of connection of electrodes with Potenciostat VSP, and program which is used for the simplification of processing of results. The main aim of this bachelor thesis is to get better understanding of lead-acid accumulators and impedance measurements. At practical part of the thesis I performed first measurements by two-step method based on electrochemical impedance spectroscopy.
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Using lead-acid accumulators in hybrid electric vehicle regime
Klojda, Viktor ; Vaněk, Jiří (referee) ; Bača, Petr (advisor)
This bachelor´s thesis is focused on utilization of maintenance-free lead-acid accumulators in hybrid electric vehicle regime. It describes paralel and serial draft of hybrid vehicles, their function, advantages and disadvantages. It compares lead-acid accumulators with other sorts of primary, secondary and fuel cells. Purpose of this thesis is to improve the lifetime of lead-acid batteries in PSOC regime and accompanying addition use, as an activ material of negative electrode.
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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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Development of autonomous fotovoltaic system
Svoboda, Luboš ; Vaněk, Jiří (referee) ; Bača, Petr (advisor)
The project considers realization system, which will allow us to test six different operation modes on lifetime accumulators. The system will link to computer, which will execute measurement current and tension and switch betwencharging and discharging modes. The measured values will record in someone time intervals in to computer memory. After someone time will analise these measured valuer and will provide optional operation mode.
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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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