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New gel electrolytes based on copolymers for electrochemical power sources
Peterová, Soňa ; Sedlaříková, Marie (referee) ; Veselkova, Iuliia (advisor)
This thesis deals with description of preparation and use of monomers and copolymers for gel polymer electrolytes usable in electrochemical power sources. This thesis is divided in theoretical and experimental part. The theoretical part describes electrolytes focused on gel polymer electrolytes, measuring methods and materials used for experiments. The experimental part deals with calculation of composition of polymer electrolytes, method of preparation and evaluation of measured results. The method of applying GPE to a negative LTO electrode and a positive NMC electrode is described too. Linear Sweep Voltammetry (LSV) and Potentiostatic Electrochemical Impedance Spectroscopy (PEIS), Cyclic Voltammetry (CV) and Galvanostatic Cycling with Potential Limitation (GCPL) were chosen for measurement of properties.
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Low NOx emission combustion chamber of turbine engines
Šafránek, Martin ; Mašek, Jakub (referee) ; Šplíchal, Miroslav (advisor)
Bachelor thesis examines Low NOx emission combustion chamber of turbine engines. It describes in particular the events taking place in the combustion chambers and the mechanisms of generating all monitored emissions. It also focuses on the description of the most important design parameters, their estimated development, assessment and use in civil aviation. Further, this thesis deals with the legislation of various organizations that create certification standards for regulating the amount of emissions emitted.
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Data backup technology with a focus on backup between remote sites using the EMC Avamar deduplication backup
KINDELMANN, Ladislav
The aim of this dissertation is to analyze the way data backup of remote sites deduplication technology system used by EMC Avamar. This is a special type of data compression used not only when saving to disk arrays, but also in a virtual environment. Deduplication ensures saving storage space and reliability of data recovery. EMC Avamar system is one of the best-engineered and most extensive systems of which the above technology is used. The dissertation is divided into two parts - theoretical and practical. In the theoretical part student briefly summarize the available backup technologies and describes the remote backup methods, including examples using available software and hardware requirements. Then it specifies details of EMC Avamar and its implementation, HW requirements and functioning of the entire system. Student will analyzes the data deduplication technology, which the system uses, description of data transferring and the possible advantages and disadvantages compared to other systems. In the practical part it creates own proposal for implementation of data backup using the above mentioned system in a business environment between the two branches of the company. The aim will be to show the real technology features, advantages and shortcomings. The conclusion of the dissertation the student all accompanied overview of the use of backup systems in today's global market.
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Expanded Grpahite as Negative Electrode Material for Aporotic Intercalation Systems
Kaňa, Michal ; Čech, Ondřej (referee) ; Libich, Jiří (advisor)
This thesis deals with lithium-ion batteries. It focuses primarily on the materials which are the basis of negative electrode materials, especially on natural expanded graphite. The aim of this thesis is delineate problems of lithium-ion batteries and the possibilities how to improve their basic parameters such a capacity and current carrying capacity. The first part focuses on the description of the functionality of a lithium-ion battery. The second part focuses on the production of negative electrodes, measuring their properties and characteristics. In the last part, there are evaluated and compared individual negative electrode in the role of host of lithium and sodium ions according to the obtained data and then there are the conclusions draw
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Methods for Analysis of Switched Circuits
Kovář, Jan ; Ondráček, Oldřich (referee) ; Kalous, Jaroslav (referee) ; Kolka, Zdeněk (advisor)
The dissertation deals with simulations of the DC-DC converters in their basic configurations (Buck, Boost, Buck-boost, Cuk, SEPIC). In the first part of the thesis derivation of transfer functions Line-to-Output (LTO) and Control-To-Output (CTO) can be found. These symbolic responses are derived for three types of basic converters (Buck, Boost, Buck-boost) using well-known average model [1]. Derived expressions are very complicated. For reduction of these expressions symbolic approximation method was used, however the generality is lost. The average model was used to for decreasing the computational effort of analysis of DC-DC converters in the time domain. For these simulations VHDL-AMS language was used. The main topic of the thesis is harmonic balance method, which was adapted to DC-DC converters. Because conditions and assumptions for LTO and CTO functions are very different, harmonic balance method was derived into two variants. For obtaining of LTO response, duty cycle of switching signal can be considered as constant in time. Spectrum of this signal is simple as follows from well-known sinc function. For obtaining of CTO response PWM modulation must be used. Compared to sinc function spectrum of PWM modulation is richer (contains more combination frequencies). Many types of PWM modulation is described in [31]. For simulation PWM modulation with uniform sampling in two variants (single and double edge) was used. Non-ideal switching of PWM switch was modeled by PWM pulse with defined slew rate. Last section deals with comparison of all derived functions (LTO, CTO, modulation type, defined slew rate) with well-known averaged model.
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Compatibility of negative electrode materials at system of lithium-ion battery
Šikuda, Milan ; Sedlaříková, Marie (referee) ; Libich, Jiří (advisor)
This thesis deals with a study of lithium-ion batteries. It is focused into negative electrode materials and electrolytes. In this thesis is presented synthesis, electrochemical properties, possibilities to improving negative electrode materials as LTO (Lithium Titanate Oxid) and graphite. These electrode materials were investigated with respect to their compatibility at electrolytes with carbonate solvents, Sulfolane and DMF (DiMethylFormamide) in detail. The main aim of this thesis is to characterize electrode materials and electrolyte properties depending on wide range of temperatures and their comparison for the purpose of achievement of the best solution. The thesis is divided into two main parts. The theoretical part of thesis describes composition, process of synthesis and analysis of lithium-ion cell. Practical part contains measuring and evaluating of charge-discharge and irreversible capacity characteristics related to variety of environmental temperatures.
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