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Influence of the pulse charge on properties of the lead acid batteries
Zbožínek, Štěpán ; Vaculík, Sebastian (referee) ; Křivík, Petr (advisor)
The presented master´s thesis deals with lead-acid batteries and methods of their charging. First part shortly describes the problems of lead-acid batteries. There are introduced common principles, type of construction and requirements, that should be complied with lead-acid batteries. Following part discusses the basic characteristics of charging. There is given a detailed description of current pulse charging method, on which is also mainly focused this master´s thesis. For this charging method, several basic experiments were done in order to verify functionality of the measuring device, software, the tested cells and primarily to verify charging modes. The goal of this thesis is to find out suitable mode of pulse charging, which would be fast as well as tested cells-friendly. The conclusion of this master´s thesis contains a resume of acquired theoretical knowledge and an evaluation of measured results, on which was the appropriate charging mode proposed.
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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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Wind power generation and energy accumulation possibilities
Krbal, Michal ; Mastný, Petr (referee) ; Drápela, Jiří (advisor)
The goal of this bachelor’s thesis is to inform about conditions of running and the character of running of the wind power plants and about the suitable storage systems for the possibilities of time invariableness of power supply. For these reasons is immediately in the first chapter of the thesis described state of using wind power plants in The Czech republic and other countries in Europe which produce electric power. Description of individual functional parts is important mainly from the point of electrician conversion of kinetic energy of wind to electric energy with help of the electric power generator with the highest efficiency and without need for maintenance. It is necessary to know those functional parts of the power wind to be able to design appropriate storage system. The output electric power is very variable at time, mainly output voltage, because wind energy is variable too. The characteristics of the wind power plants as output voltage, frequency and their switching graded at time have to in accordance with requirements of the electricity supply systems not to disturb the stability or even collapse of the electricity supply system which would lead to serious economic consequences. These predicaments can be prevented with precise meteorological forecast or by using the acceptable storage system with small acquisition and operating costs, requirements to safeness and long service life, low weight and high efficiency of conversion of energy. The storage systems are classified into centralized and decentralizing systems with requirements to dynamic running and running time. To fulfil these conditions it is essential to choose acceptable and accessible locations with year lasting qualities of wind, which are being checked in advance using measurement and mathematical calculations.
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Optimalization of pulse charging mode of lead-acid battery
Sygeryč, Daniel ; Vaněk, Jiří (referee) ; Křivík, Petr (advisor)
This thesis deals with pulse charging lead acid batteries. The theoretical part provides the basic electrochemical reactions that take place in the lead pack, then this section discusses important parameters of lead-acid battery, its structure and distribution of the various types depending on the application. The next section describes the theory of charging lead-acid battery. The practical part deals with constructing experimental cells, which are then tested. The subject of the experimental execution and optimization of pulse charging modes in order to find a suitable pulse mode, which reduces the duration of charging, while significantly shorten the life of lead-acid battery.
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Examination of temperature changes in lead-acid battery system
Starý, Viktor ; Křivík, Petr (referee) ; Bača, Petr (advisor)
In the automobile industry is always more often talking about hybrid electric vehicles at the present. Functioning of these hybrid automobiles is provided by source of energy. This source is represented by accumulator. When accumulator is working we can see temperature changes. This project is dealing with used types of accumulators for hybrid electric vehicles. In the second phase is dealing with enquiring of temperature changes during different modes of operating.
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Lighting and lighting systems for stand-alone applications
Čejka, Lukáš ; Škoda, Jan (referee) ; Baxant, Petr (advisor)
This bachelor's thesis deals with the issue of lighting systems for stand-alone applications. These systems are independent of the electrical connection and they are powered by batteries. Batteries are charged by independent sources. The work is more focused on an autonomous lighting system that uses a solar panel. It mentions the main components of the system. Furthermore, in this work, we can find types of stand-alone lighting applications, their possibilities, problems, advantages and disadvantages, economic balance and also outline other possible solutions.
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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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