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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Elektrolyty pro sodno – iontové akumulátory s použitím iontových kapalin / Electrolytes for sodium - ion batteries using ionic liquids

Suský, Stanislav January 2021 (has links)
The content of this work deals with a theoretical search of sodium-based batteries. The first part of the work contains an introduction to the issue of batteries, contains basic concepts, principles of secondary batteries. In the second part, the basic three divisions of sodium batteries according to the design principles are discussed in more detail. He also deals with the theory of ionic liquids. Their mechanical, thermal and electrical properties and the method used to measure electrolytes are described here. The practical part describes the measurement procedure, displays the recorded measured values and their evaluation.
32

Řízení výkonové LED pomocí ATtiny / Controlling a power LED using ATtiny

Holubčík, Jiří January 2008 (has links)
This master´s thesis puts mind to choice and suggestion of suited type of DC/DC tension converter for power supply of power LED. It shows comparison of available types of accumulators in The Czech Republic and types of DC/DC converters used in construction of the sample. The choice of available source of energy is subordinated to final weight and size of a battery. There are also some explicit requirements for the smallest possible size and highest effictivity. So the choice is aimed only for converters with a simple coil and minimum numbers of switching elements to realize the converter, for example by SMT technology. One of many possibilities is LTC3453 circuit, which is described in this thesis, assembled and measured. On the basis of this circuit the next two samples are assembled. Here I try to suppress problems from previous circuit and expand it´s possibilities by adding the control of luminance via the microcontroller ATtiny. Then is introduced the basic description of flashlight Petzl MYO XP which is available in stores.
33

Zkoumání vlivu přítlaku na životnost olověných akumulátorů pro hybridní elektrická vozidla. / Investigation pressure effect on lead-acid accumulator lifetime for hybrid electric vehicles.

Kulhány, Andrej January 2010 (has links)
The thesis is focused on remitting lead-acid segments of partial charge mode which simulates the conditions in HEV. The experimental cells were submitted to different pressures on the electrode system. The main aim of the thesis was to minimize the irreversible sulphating of the negative electrodes, which are in the PSoC regime limiting in the overall life of lead-acid accumulators. All cells were submitted to measurement of the negative electrode potentials, resistance of active materials, contact resistance of the grid – the active material and measurements of pressure changes during three PSoC cycles.
34

"Smart" tester a nabíječka akumulátorů / Smart accumulator tester and charger

Mílek, Čestmír January 2010 (has links)
Nickel cadmium and nickel metal hydride accumulators sets are currently used for supplying hand tools (screwdrivers,...). Problems of cheap hand tools are chargers, mostly of it doesn’t use any charging driving circuits. In consequence of it the accumulators are kept incorrectly, which causes lowernig of lifetime. This thesis suggest circuit design Main of intelligent charging system, which enable better battery management, increases battery lifetime and lower load of environment.
35

Automatický nabíječ akumulátorů pro zdravotnické přístroje / Automatic battery charger for medical equipment

Talanda, Oldřich January 2010 (has links)
The goal of this thesis is describe properties accumulators used in medical industry and proposal automatic baterry charger for medical equipment. The first part of the master’s thesis describes the most commonly used types of electrochemical accumulator systems used in the medical industry. Further listed are the criteria for the identification of the accumulator charge status. The second part of the master’s thesis defines demands on automatic baterry charger and proposal factual network solution.
36

Optimalizace a metody měření vnitřního odporu článku olověného akumulátoru / Optimalization and methods of internal resistance measurement of the lead acid battery cell

Fojtlín, Branislav January 2013 (has links)
The aim of this master´s thesis is optimalization and methods of measuring the internal resistance of lead acid accumulator. First focus is on the analysis of properties of lead acid accumulators, their construction and negative effects. After that a method of measuring the internal resistance of experimental accumulator is processed. In this thesis practical design of measuring workplace is completed. The frequency analysis of impedance of charging and discharging accumulator is performed. After that the graph of internal resistance for various amplitude intensities, for various signal forms and also for various size of frequencies of alternating current are processed. The result of this thesis is a comparison of graphic works addictions charging and discharging characteristics of lead acid accumulator and determination of optimal amplitude, form and intensity of frequency of alternating current in point when internal resistance is evaluated correctly.
37

Analýza teplotních dějů uvnitř článku olověného akumulátoru / Analysis of thermal processes inside of lead acid battery cell

Starý, Viktor January 2013 (has links)
Lead-acid battery is one of the most widely used electrochemical cells. These batteries have been associated with supplying energy to start the car. Currently used for propulsion and the overall operation of hybrid electric vehicles. When operating lead-acid batteries are made inside cell the thermal happens. The thermal going generate heat caused by chemical reactions during charging and discharging of the electrochemical system, the heat generated by ohmic and polarization losses and heat mediated contact with the environment. In this diploma thesis shows the principle of lead-acid battery and thermal processes that take places in the accumulator during its operation.
38

Kyslíkový cyklus při pulzním nabíjení olověného akumulátoru / Oxygen cycle during pulse charging of lead-acid accumulator

Havlíček, Jiří January 2015 (has links)
This master´s thesis applies to puls charging of lead-acid accumulator and arising oxygen cycle while charging. First part of the thesis is focused on potential dividing of lead-acid accumulators and their construction. I also focus on priciples of submerged electrodes accumulator, gel accumulator and AGM accumulator based on oxygen cycle. The next topic are thermal and degradation processes inside accumulators and their influence on capacity and lifespan. In theoretical part am I describing ways of charging and I also point out possitives and negatives. Practical part focuses on producing experimental cell and its form. Experimental cell is tested to different modes. I evaluate their influence on temperature inside the cell, intensity of oxygen cycle and capacity. I compare their influence on duration of charging cycle to another possible charging modes.
39

Vanadové články jako zdroje a akumulátory energie / Vanadium cells as a source and storage of energy

Langr, Pavel January 2015 (has links)
This semestral thesis deals with problematics of redox flow batteries, especially vanadium batteries. The first part is focused on describing basic terms, describes redox batteries and explains chemical processes. It also deals with vanadium batteries properties and construction. The second part of the thesis describes diagnostic method of spectroscopy, which seems to be very perspective for examining attributes of vanadium redax batteries.
40

Elektrický pohon motocyklu / Electric drive for motorcycles

Černošek, Martin January 2013 (has links)
The diploma thesis is focused on rebuilding of the combustion engine powered motorcycle to the electromotor powered motorcycle. In the thesis is chosen the suitable electromotor, next is designed the accumulator system, then is created the construction design of location electric system in the motorcycle frame and at the end is made the strength analysis of the mechanical parts. For the construction design is created 3D model in SolidWorks. The diploma thesis is also focused on comparison the motorcycle powered by combustion engine and the motorcycle powered by electromotor in the Supermoto race.

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