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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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Binders for supercapacitors electrodes
Gottwald, Tomáš ; Dvořák, Petr (referee) ; Sedlaříková, Marie (advisor)
This work deals with the issues of useing binders for supercapacitor electrodes and optimizing the technological process for their production. The work focuses on optimizing the amount of binder used in order to acheive the most capacity. The methodology consists of creating an appropriate experimental electrode and subsequent measuring its associated capacity with AutoLab. This aproach leads to creating grafs which show the dependencies of capacity on the amount of binder used.
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Composite electrode materials for lithium-ion batteries based on LiFePO4 prepared using GAC method
Vilhelm, Ondřej ; Neoral, Jiří (referee) ; Čech, Ondřej (advisor)
Presented work investigates the problem of secondary lithium-ion cells and the different available cathode materials. We have prepared samples of LiFePO4 with the addition of different kinds of carbon materials such as Super P, Vulcan and expanded graphite. We have always created the sample with and without surfactant. Developed samples were compared by measuring electrochemical methods (cyclic voltammetry, charge and discharge cycles and impedance spectroscopy). We also modeled the three-point cell for measuring electrochemical electrode materials.
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Optimalisation of coposite materials for civil engineering
Kazda, Tomáš ; Chladil, Ladislav (referee) ; Novák, Vítězslav (advisor)
This work is focused on optimalisation of coposite materials for civil engineering. In the theoretical part of the project is introduction of the composite materials and materials which are used for their production. There are also concerned their properties and possible application areas. In conclusion of theoretical part this project is a summary of the possible use of composite materials. The practical part compares the characteristics of the different types of composites made in terms of conductivity and the rate of corrosion.
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Carbon materials for power sources
Tichý, Jiří ; Bača, Petr (referee) ; Novák, Vítězslav (advisor)
This work deals with carbon materials and using them in electrochemical energy sources. Object of this work was to prepare carbon materials and investigate their electrical properties. The theoretical part objects of the carbon materials, their properties, application in electrochemical energy sources and measurement methods used in experimental part. Experimental part describes the preparation of the electrodes with various carbon materials and summarizes the results of measurements.
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Investigation of carbon effect in negative active mass on lead-acid accumulator for HEV.
Tonar, Karel ; Křivík, Petr (referee) ; Bača, Petr (advisor)
The lead-acid bateries for hybrid-electric vehicle (HEV) working under high-rate partial-state-of-charge (HRPSoC) conditions. The negative plates of lead-acid batteries have low charge acceptance. The cycle life of the batteries is dependent on the rate accumulation of PbSO4 on the negative plates. Addition of some carbon or graphite forms to the negative paste mix improves the charge efficieny and slows down sulfation of the negative plates. The master’s thesis wants to explain the contribution of electrochemically active carbon (EAC) additives to the mechanis of the electrochemical reaction of charge of the negative plates.
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Conducting polymers and their use in supercapacitors
Gottwald, Tomáš ; Zatloukal, Miroslav (referee) ; Dvořák, Petr (advisor)
This work deals with the issues of using conducting polymers for supercapacitor electrodes and optimizing the technological process for their production. The work focuses on optimizing the amount of polymer used in order to achieve the most capacity. The methodology consists of creating an appropriate experimental electrode and subsequent measuring its associated capacity with BioLogic. This approach leads to creating charts which show the dependencies of capacity on the amount of polymer used.
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Factors influencing the Character of Phase Transformations in the Fe - C System
Gubán, Ivan ; Němec, Karel (referee) ; Molliková, Eva (advisor)
The goal of this thesis is the study of the factors influencing the character of the phase transformation in the Fe-C system. Focusing on the speed of the cooling of alloys under the consideration and concentration of carbon in the alloy, which influences the form of carbon gelling in the alloys of iron and the resulting structure of the material. Because of the limited range, the thesis does not take into account the influences caused by the presence of the impure and alloying elements. The illustrations of the microstructure of the particular alloys or their schematic illustration. In conclusion, there is included transformation diagrams of the particular steel.
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Preparation of 2D heterostructures
Ředina, Dalibor ; Hrabovský, Miloš (referee) ; Bartoš, Miroslav (advisor)
This bachelor's thesis refers about preparation of 2D hetestructures here at the IPE, BUT. The first theoretical part deals with properties of graphene, molybdenum disulfide and 2D heterostructures in general. Comprehensive overview is provided by basic facts about properties and allotropic modifications of carbon. Next part of this thesis outlines methods used in the fabrication of heterostructures and highlights presumably the best one. Experimental part deals with optimization of this method. Successive steps of this method are improved by various adjustments in order to achieve the highest success rate in the fabrication of these heterostructures. Result of this approach is stated in this thesis.
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