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Properties of carbon materials for supercapacitors
Štorek, Ondřej ; Dvořák, Petr (referee) ; Sedlaříková, Marie (advisor)
The Master’s Thesis deals with supercapacitators based on principle of eletrical double layer. At the outset there is an explanation of supercapacitor working principal. We discussed advantages and disavantages supercapacitators compared with other related elements in electrotechnics. Materials based on carbon and their structure for production supercapacitators are described too. In next part of Thesis we mention different methods and techniques for the measurement and the evaluation of supercapacitators‘s capacities. Optimal materials for production supercapacitators are presented in conclusion.
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Properties electrodes materials for alcaline accumulators
Řihák, Lukáš ; Vrbický, Jiří (referee) ; Sedlaříková, Marie (advisor)
This thesis is involved in basical properties of electrode materials for alkaline accumulators. This thesis describes the possibilities of capacity stabilisation of nickel electrode to be stable for highest number of cycles. Thesis also consider modification of properties of electrode materials on the base of nickel hydroxide by using dopes (aluminum, manganese). Measuration proceeded on the thin film electrodes created by electrodeposition. Measuration of properties of electrodes proceeded by cyclic voltammetry and frequency analyzis.
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The influence of alcaline accumulators loading on their parameters
Čech, Ondřej ; Vrbický, Jiří (referee) ; Sedlaříková, Marie (advisor)
This master's thesis deals with alkaline battery characteristics and it has special consideration of nickel-cadmium cells. There are three main experimental parts in this paper. First one is concerned with positive electrode materials properties and is aimed to investigate impact of magnesium ions formed into nickel hydroxide electrode structure. Second part deals with battery charging/discharging and response measurement tool design. National Instruments hardware PXI modules for data acquisition was used and program in LabView environment was made. Last one is concerned with nickel-cadmium cell properties changes during increased temperature stressing. Investigation of cell self-charge changes during lithium hydroxide addition into electrolyte was made.
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Electrodes for electrolyser
Kaňa, Ondřej ; Knotek, Tomáš (referee) ; Sedlaříková, Marie (advisor)
In my diploma work i focus on the production hydrogen by electrolysis of water using by electrolyzer. Especially, i concentrate on preparation electrodes for laboratory electrolyzer. I work on principles of increasing electrodes area, increasing functional surface of electrodes, by Nickel – Zinc coatings. By electroplating or chemical plating we spread microlayer of Nickel-Zinc onto electrodes made of steel plate. Then, in alkali - hydrate oxide, we will corrode Zinc components off the alloy and this is how we create pore surface of electrode. From macroscopic view, electrode has same geometrics propositions, however from microscopics view, the electrode has bigger surface area. The hydrogen production increases with unchanget sizes of electrolyzer.
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Thin layer for electrochromic devices
Pelčák, Vít ; Macalík, Michal (referee) ; Sedlaříková, Marie (advisor)
This diploma thesis deals with creation of transparent conductive layers on glass substrate, which serve as underlay for electrochromic layers. Zinc acetate dissolved in methane and distilled water serves as basis of solution. We are searching for optimal amount of either Fluor or Boron in depositted solutions to achieve best transparency and layer conductivity.
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Liquid aprotic electrolytes with TiO2 a Al2O3 nanoparticles
Tomeš, Petr ; Krejza, Ondřej (referee) ; Sedlaříková, Marie (advisor)
The first part of this diploma thesis is dealing with conductivity of liquid electrolytes. The second part is about third generation gel electrolytes and thein conductivity. The electrolytes were inorganic salts LiClO4, LiBF4 and NaClO4 in an aprotic propylene carbonate (PC) -used as a solvent. Nanosized Al2O3 and TiO2 particles were, proportionally to the sample's volume, added to the both – blend and gel samples in an amount expressed by weight percentage (wt). Both liquid and gel electrolytes contained following amount on nanosorbent: 3,46% wt, 7,17% wt, 10,0% wt and 12,0% wt. The liquid electrolytes were gelled using commercially available precursor Superacryl (Spofa dental s.r.o.).
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Electrolyzer for hydrogen production
Kunovjánek, Miroslav ; Knotek, Tomáš (referee) ; Sedlaříková, Marie (advisor)
The work is concerned with a production of hydrogen and oxygen through by the help of electrolytic process in a device called electrolyzer. The basis of the work is assurance of the best efficiency of this process by testing a variety of materials and surfaces of electrodes, and testing different types of alkalic electrolytes.
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Liquid electrolytes for supercapacitors
Bill, Jan ; Dvořák, Petr (referee) ; Sedlaříková, Marie (advisor)
This work deals with the preparation of liquid electrolytes from different types of aprotic solvents with the aim of their application as electrolytes in electrochemical supercapacitors. Different sorts of aprotic solvents have been chosen, in which the following forms of salts were used: LiBF4, LiClO4,LiPF6. In the next part of the work, the properties of these solvents were measured and the best electrolyte, according to the biggest possible capacity of the system, was chosen. In the theoretical part of this work, the physical principle of supercapacitors and their propeties are described. It deals with electrolytes, their division and with the properties that are appropriate for supercapacitors. The experimental part of the work describes the process of preparation of the samples of electrodes, electrolytes and the techniques of measuring their capacities.
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