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Case "Kramný" of Perception of the guilt of alleged perpetrators based on diverse media coverage
Kazda, Tomáš ; Končelík, Jakub (advisor) ; Vranka, Marek (referee)
The case of Petr Kramný, who allegedly killed his wife and daughter in Egypt, has been printed in the memory of the Czech nation since 2013. Both because of its tragic and ambiguous circumstances and, above all, because of the media coverage of the case, which is the subject of this thesis. The "Kramný" case serves as a template of an actual "media trial", which examines the effect of tabloid and public media coverage via an online questionnaire. Respondents, randomly assigned to one of two groups, learn about the case of Matúš L., who allegedly killed his girlfriend. However, in reality, they read articles about the "Kramný" case - one group from the private platform blesk.cz, the other from the public media ct24.cz. The restrained and distant attitude of ČT contrasts with the sensationalist narratives longing for drama presented by Blesk. The results of the quantitative analysis confirm the hypothesis that tabloid coverage leads not only to a higher degree of guilt attributed to the accused but also to a more negative evaluation of his character traits. The accused's behavior is perceived as more suspicious by tabloid respondents, while these respondents also possess greater confidence in the strength and quantity of evidence. Although these findings do not necessarily imply any threat to the...
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Review of In-situ and Ex-situ Techniques for Characterization of Li-ion Batteries
Klvač, Ondřej ; Kazda, Tomáš
This paper describes the analytical techniques andsample preparation methods used in in-situ and ex-situ investigationsof Li-ion batteries (LIBs). The introduction briefly describesthe current state of Li-ion batteries and their aging mechanisms.The article is further divided into a description of ex-situ and insitutechniques. Ex-situ techniques include a detailed descriptionof sample preparation for repeatable results using Broad IonBeam (BIB) polisher. In-situ techniques are described in theform of a report of selected published experiments. The paper isfurther extended with our experiments involving ex-situ analysesof cylindrical and flat cell types using BIB in planar modeand cross-section mode. In the case of in-situ experiments, thedesign of the cell inside the SEM chamber is described. Twoexperiments have been performed - on the surface of a MEMSchip, and also using a micromanipulator as a current collectorof the investigated electrode.
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Recovery Of Anode Material From Lithium Ion Batteries
Báňa, Jiří ; Kazda, Tomáš
As the production of lithium-ion batteries (LIB) is growingat a meteoric pace with the advent of electromobility. There willbe a need for efficient use of recycling processes, which nowfocus mainly on selected metals. Direct recycling is a methodwith great potential due to its simplicity, ecological friendliness,and high efficiency. However, this method needs to be improvedand put into practical use. In this paper, it is focused thesimulation of LIB aging, composition analysis and then recoveryof the anode material of Motoma LFP 18650 and PanasonicNCR18650B batteries.
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Synthesis of Perspective materials for cathodes of Li-ion batteries with low cobalt content
Hálová, Hana ; Kazda, Tomáš (referee) ; Chladil, Ladislav (advisor)
The thesis is focused on cathode materials with low cobalt content. In the work, there is a comparison of cathodes with cobalt, low cobalt content, and without it. The materials are compared in terms of theoretical specific capacity, commonly achieved specific capacity within first cycles, energy density, and cycle life. Taking into account these criteria there have been selected perspective high voltage cathode materials. For selected cathode materials, various synthesis options were compared, with spray-drying synthesis chosen for the research conducted within the experimental part of the thesis. The thesis also describes the preparation of a laboratory apparatus for spray-drying synthesis, including a particle capture system. Furthermore, systematic experiments were carried out to optimize the high-temperature calcination process.
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Design of a calorimeter to characterize the properties of commercial batteries
Gavalierová, Veronika ; Šedina, Martin (referee) ; Kazda, Tomáš (advisor)
This thesis is focused on the study of the heat capacity of Li-ion cells. The theoretical part contains the basic issues of the technology, basic concepts, and knowledge. The next chapter, the practical part, is devoted to the practical measurement of the specific heat capacity of batteries, using a calorimeter. Various types of batteries were investigated, and a larger calorimeter was also constructed and described. This bulkier calorimeter was used for a larger pouch cell.
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Inverse vulcanised sulphur as an electroactive material for lithium-sulphur and sodium-sulphur batteries
Trochta, David ; Kazda, Tomáš (referee) ; Čech, Ondřej (advisor)
This thesis deals with the study of lithium-sulfur and sodium-sulfur batteries, which are designed for use at room temperatures. Both of these systems are interesting mainly due to their high theoretical capacity and low environmental impact, thus greatly outperforming lithium-ion batteries. The weakness of these new technologies is their low lifespan and the associated rapid loss of battery capacity. To increase the lifespan, elemental sulfur in this work was replaced by sulfur with an amorphous structure, synthesized by an inverse vulcanization process that has been optimized in various ways. In addition to the optimization of the inverse vulcanization technology window, the effect of the addition of carbonaceous additives during the synthesis was also investigated. In this work, a series of samples of inverse vulcanized sulfur with different ratios of input precursors were prepared and also with different additives. X-ray diffraction was used to confirm the amorphous structure of the material, which also excludes the presence of crystalline sulphur. The results of Raman spectroscopy were also presented, demonstrating the possibility of using this method to determine semi-quantitative ratios of the input precursors. Electrodes for electrochemical cells were fabricated from selected samples. The homogeneity of the distribution of the electroactive material on the electrode was investigated using a scanning electron microscope and elemental mapping by energy dispersive spectroscopy technique. The electrochemical characterization of the inversely vulcanized sulfur electrodes was carried out by cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic potential limited cycling.
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Intelligent BMS for lithium batteries
Vašíček, Jakub ; Kazda, Tomáš (referee) ; Vyroubal, Petr (advisor)
This thesis is focused on design of electronic system called BMS, which is necessary for lithium batteries safety operation. The first part contains a brief description of lithium battery design. The following is an overview of the main parameters of this type of batteries. The next part describing various methods of state of charge (SoC) estimation and the ways to ensure uniform charge of each cell. Based on the theoretic analysis, the block diagrams for individual parts of BMS were designed. The following describing device assembly and design of control algorithm. The last part is devoted to measurement of achieved attributes. In conclusion, results of the work are discussed and possibilities of future improvements are suggested.
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Analysis of critical parameters of the batteries for space applications
Šimek, Michal ; Šedina, Martin (referee) ; Kazda, Tomáš (advisor)
This thesis deals with the use of lithium-ion batteries for space applications. Primary and secondary electrochemical sources and their comparison are described in the paper. The main part of this work deals with lithium-ion batteries, their history, properties and used materials, deals with the use of li-ion batteries for space applications in terms of temperature and describes the effects of temperatures on li-ion batteries. At the last chapter deals with a lithium plating and his detection. In the practical part, a methodology for the detection of cast plating is proposed, which I then test on a number of cells, which I measure at various practical workloads.
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