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Lead-acid baterry charger with automatic cycle
Moravec, Pavel ; Friedl, Martin (referee) ; Steinbauer, Miloslav (advisor)
The lead-acid batteries are still important and very often used type of battery even in 21st century. This project is focused on development of charger, which provides fast, but save charging of batteries with respect to maximum life time and reliability. The developed system uses constant current charging and constant voltage charging methods. It's specialized in charging batteries with liquid or gel electrolyte and traction types of batteries, which works with 12 V value of voltage. It's able to charge safely the deeply discharged batteries and when battery is unpluged for a long time, it can keep its capacity at maximum level too. The charger can choose optimal charging process according to the discharged level of battery. Each charging phase is interpreted by light signals and the achievable charging current is 20 A.
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Optimization of use properties Lead-Acid batteries
Lábus, Radek ; Dostál, Zdeněk (referee) ; Jareš, Petr (referee) ; Křivík, Petr (advisor)
This thesis focuses on the limitations of degradation mechanisms of Lead-Acid batteries, which significantly contributes unequal distribution of current (and therefore internal resistance, charge passed and power loss) on the surface of the electrodes of Lead-Acid battery. The unevenness of distribution of these parameters significantly influences the distribution of current tabs on the electrodes. In this work it was developed realistic model of Lead-Acid battery cell with plate electrodes with different variants of the distribution of current tabs. Measured results obtained in this model were compared with the results found out from the mathematical simulations. Through these simulations, it was possible to take a look deeply into the processes and changes in the electrodes of Lead-Acid batteries during discharge. Goal of this work was for predefined variants of positioning of the current tabs to simulate distribution of current, internal resistance, charge passed and power loss during discharge. Another goal was to compare the different variants and to find the optimal variant of current tabs positioning based on minimizing of unevenness of examined variables distribution.
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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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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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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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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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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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Temperature changes during pulse charging of lead-acid accumulator
Přikryl, Kamil ; Bača, Petr (referee) ; Křivík, Petr (advisor)
This master's thesis deals with the issue of lead-acid batteries, their charging methods and issue of thermal processes in lead-acid batteries. The thesis is divided into three main parts. The first section describes the theoretical knowledge of lead-acid batteries, such as history of lead-acid battery, structure, principle of operation, methods of charging and thermal processes taking place in the lead-acid battery. The second part describes in detail the production of experimental electrodes. The last section describes the automatic data logger for measuring and experiments, which were focused on pulse charging method with variable duty cycle pulses.
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