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Temperature changes in lead-acid batteries
Grepl, Jan ; Chladil, Ladislav (referee) ; Bača, Petr (advisor)
The aim of this thesis is familiarization with the basic lead-acid batteries construction with specialization on their differences. This work is divided in theoretical part and practical part. At first, the theoretical part deals with basics of functions of electrochemical cells and their fundamental division. In the case of lead-acid batteries the work focuses on the fundamental chemical reactions and fundamental principle of their construction. Aftwerwars are also in this part included negative phenomena, which can occur during the operation of the lead-acid batteries and possibly decrease their capacity or shorten their lifetime period. In practical part takes part description of measuring station. Subsequently is realised the correction of masurement sensors. Finally there takes place an analysis of measured parameters in experimental cell in CC and CC/CV charging mode.
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Design of a kit for the creation of a supply point for electricity generated from renewable sources
Fridrich, Jiří ; Zimáková, Jana (referee) ; Binar, Tomáš (advisor)
This project deals with the design and realisation of a set that will work as a power supply point with electricity generated from renewable energy sources. The theoretical part deals with information about renewable energy sources and energy storage options. In the practical part, a mobile kit for powering variable message traffic signs is designed. It uses photovoltaic panels and stores energy in a lead-acid battery. A methanol fuel cell is used for backup power. The device is adapted for use in road traffic and meets the requirements of the relevant authorities. To verify the stability of the structure, there were performed static calculations, which proved the ability of the device to withstand wind stress. Part of the work was to draw a complete production documentation, which was used to create a test sample. Long-term measurements of energy flows in the system were performed on that sample. These measurements confirmed the ability of the device to operate autonomously and the possibility of using it for the required purpose.
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Lead-Acid Battery Evaluation Based On Opencircuit Voltage Fluctuation Measurement
Kuparowitz, Tomáš ; Kuparowitz, Martin
The state of charge and the state of health are two crucial parameters of batteries. Current state of the art methods of their estimation include some as simple as measuring open circuit voltage, all the way to fuzzy logic estimation and constant online battery overview. Some main problems of such methods are either the length of single parameter evaluation cycle, or their inherent inaccuracy due to limitations in battery manufacture precision. This article proposes novel method of the lead-acid battery state of the health estimation, based on open circuit noise measurement. It reports the nature of changes in low frequency noise spectral density, that occur after catastrophic self-discharge failure or avalanche voltage drop in lead-acid batteries.
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Cycling Of Vrla Lead-Acid Batteries For Use In Uninterruptible Power Supplies And Measurement Of Failed Batteries
Musil, Petr
This article deals with study on the influence of cycling of batteries with regard to their parameters. Electro-chemical reactions which take part in battery cells are described. This paper also offers a measurement scheme for automated measuring workstation. Furthermore, results of measurements are being presented on measured parameters of chosen batteries. Comparison of the measurements results and datasheet values is included. Conclusion sums up parameters of chosen batteries and their feasibility for further usage in Uninterruptible Power Supply as a crucial part of critical infrastructure.
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Fast-charger for lead-acid batteries 12 V
Kopuletý, Ondřej ; Pazdera, Ivo (referee) ; Vorel, Pavel (advisor)
This Master thesis deals with modification of lead battery charger connection. In particular, changes are made to the control board. The theoretical part describes the principle of charging lead batteries and the description of the basic types of switching power supplies. Furthermore, the dimensioning of important components in the circuit together with the optimization of the switching frequency and the parameters of the high-frequency transformer are also presented. At the end of the thesis is the procedure of assembling the whole charger.
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Monitoring of temperature influence on properties of lead-acid accumulators
Musil, Petr ; Křivík, Petr (referee) ; Bača, Petr (advisor)
This thesis deals with lead-acid battery, its parameters and temperature behaviour of this electro-chemical source of power. In the theory section, types of batteries are presented, followed by their primary parameters and electro-chemical reactions, which take part in battery cells. This section also contains information about charging stages, detailed description of each battery part, used materials, construction of the battery and degradation processes caused by battery operation. The practictal section of this thesis offers a measurement scheme for automated measuring workstation. Furthermore, the practical section presents results of measurements on parameters of chosen lead-acid battery types, it also contains long-term deep battery cycling and measurements under elevated temperatures. Detailed comparison of measurements results and datasheet values is included. Conclusion sums up parameters of chosen lead-acid battery types and their feasibility for further usage in power backuping.
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Pulse charging of lead-acid accumulator using negative current steps
Kantor, Pavel ; Vaněk, Jiří (referee) ; Křivík, Petr (advisor)
The lead-acid batteries are the most commonly used electrochemical power sources and are the oldest type of secondary battery cells. This master thesis provides a short introduction to the lead-acid batteries. It shows possible ways of sorting from different points of view, describes construction of lead-acid batteries, parameters of lead-acid batteries and electrochemical and physical reactions inside the battery. Futher the thesis deals with pulse charging of lead-acid batteries. The thesis describes the production of a set of experimental electrodes for electrochemical workplace resources. The thesis introduces the develepment environment Agilent VEE PRO and demonstrates its capabilities. The final part of this thesis are experiments focusing on the pulse charging using negative current pulses and evaluate the effect of different pulse modes on cells.
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Charger for lead-acid batteries
Kopuletý, Ondřej ; Procházka, Petr (referee) ; Ondrejček, Vladimír (advisor)
This bachelor‘s thesis deals with the modification, construction and testing of lead-acid battery chargers. It is described the principle of charging the batteries and individual topology of the switching power supplies. The original schematic diagram is taken from the thesis of Josef Kadlec. Diagrams of a power and control circuit have been modified. The topology of the charger is two switch forward converter with pulse transformer. The charging method is constant voltage with current limiting.
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The influence of electrolyte additives to lead-acid batteries properties
Dohnal, Martin ; Zimáková, Jana (referee) ; Bača, Petr (advisor)
This day is a lead battery is most prevalent in the automotive industry. Which is a source of energy when starting the car. In recent times the battery is used not only for startups, but also when driving in city traffic. This behavior can know the concept of a hybrid car. Which is used an electric motor which as a result reduce emissions standing cars in cities. The electric motor is powered by lead-acid battery and a rapid discharging and reducing battery life. To extend the life developed additives to the electrolyte. In the thesis, these additives investigated. If they really have a positive effect on the battery.
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Charging of lead-acid accumulator by pulse current
Jurčák, Tomáš ; Vaněk, Jiří (referee) ; Křivík, Petr (advisor)
Most used and oldest secondary current source is lead-acid battery. This bachelor´s thesis provides short introduction to lead-acid batteries, to their distribution, structure, chemical reaction inside lead-acid battery and negative effects on battery. Next part is focused on charging of lead-acid battery, here is shortly described few types of charging with emphasis on pulse charging. Last part is focused on construction of experimental electrode and experiments with pulse charging.
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