National Repository of Grey Literature 27 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Study of intercalation properties of electrode materials based on naturla graphite
Bílek, Lukáš ; Máca, Josef (referee) ; Libich, Jiří (advisor)
This diploma thesis deals with the issue of lithium-ion accumulators. The thesis focuses on the negative electrode of lithium-ion accumulators made of natural graphite. The first part of this thesis points to the issue of electrochemical cells. In the theoretical part the thesis deals with the SEI layer, advantages, disadvantages, characteristics, operating principle and the use of lithium-ion accumulators. The practical part focuses on the electrochemical properties of negative electrode, especially the determination of the diffusion coefficient. Thesis also deals with electrochemical impedance spectroscopy (EIS) and its use in determining the equivalent replacement circuit and calculating the diffusion coefficient.
Comparison of different types of commercial lithium-ion batteries and their properties under low temperature
Bičák, Tomáš ; Máca, Josef (referee) ; Libich, Jiří (advisor)
The diploma thesis deals with the issue of lithium-ion batteries. Describes development, technologies and materials used. The diploma thesis describes the operating principle, characteristics, advantages and disadvantages. The work is focused on the characteristic properties of commercial lithium-ion batteries under standard conditions and at reduced temperatures. At reduced temperatures, changes in properties due to low temperatures are observed. Furthermore, in this work they compare the measured values with the values given by the manufacturers.
Technologies for storing electrical energy in electric vehicles
Zdražil, Marek ; Walek, Agata (referee) ; Langerová, Petra (advisor)
Tato bakalářská práce je zaměřena na technologie pro ukládání elektrické energie, s důrazem na jejich použití v elektrických vozidlech. První kapitola se zabývá historickým vývojem technologií pro ukládání elektrické energie a jejich použitím v prvních elektrických vozidlech. Dále popisuje elektrická vozidla, která byla sporadicky vyráběna v průběhu dvacátého století, až po devadesátá léta, kdy tato technologie opět nabyla na atraktivitě. V další části nalezneme rozdělení současných elektromobilů a zástupce těchto kategorií mezi automobily vyráběnými v současnosti. Třetí část se věnuje technologiím používaným v současnosti, či nedávné minulosti. Následně je uveden přehled technologií, které by mohly do budoucna nahradit současné systémy, nebo dokonce konvenční spalovací motory.
A structure study of high-voltage cathode materials for lithium ion battery using X-ray crystallography
Kunický, Daniel ; Čech, Ondřej (referee) ; Chladil, Ladislav (advisor)
This diploma thesis deals with the X-Ray crystallography study of structural changes within lithium-ion cells. First part consists of the theoretical discussion about the structural changes in commerce lithium-ion cells with focus on X-Ray crystallography. Then the ex situ, in situ and operando terms are discussed. Verification of the XRD usage is realized on the LiFePO4 material. Experimental part deals with the optimization and preparation of electrochemical cells and the measurements. Finally, results of the Rietveld analysis are discussed.
Lithium-ion battery: Negative electrode materials based on graphite
Vencelides, Lukáš ; Máca, Josef (referee) ; Libich, Jiří (advisor)
This bachelor‘s thesis deals with the isuess related to the lithium-ion batteries. The history of development of lithium-ion batteries, current commercially available and developed types are described in the thesis. The thesis deals in detail with the description of the characteristics and operating principle of lithium-ion accumulators with emphasis on negative electrode and negative electrode materials. The goal of the thesis is technological and electrochemical characterization of graphite negative electrode materials. Two types of natural graphite are used in the thesis, both are potenti-galvanistically analyzed from the point of view of capacitance and current characteristics.
Lithium-ion cell: Treatment of Natural Graphite by Lithiation Method
Bílek, Lukáš ; Kazda, Tomáš (referee) ; Libich, Jiří (advisor)
This bachelor thesis deals with the issue of lithium-ion accumulators. The thesis focuses on the negative electrode of lithium-ion accumulator made of natural graphite. In the theoretical part the thesis focuses on the characteristics, the operating principle and the use of lithium-ion accumulators. Negative electrode materials are also analyzed. The main topic of the thesis is the use of lithiation method which suppresses irreversible capacity losses with the improvement of the capacitance and current characteristics of the battery.
Calandering of li-ion electrodes and its impact on the final capacity of lithium-ion cell
Svoboda, Lukáš ; Kazda, Tomáš (referee) ; Čech, Ondřej (advisor)
There is an effort to produce lithium-ion batteries with maximal density of energy, or higher capacity of cell with the same size. Calendaring of electrodes is important part of manufacturing of batteries. Its parameters, mainly the pressure of calendaring and with it related the final compression ratio of electrode layers, affect parameters of battery significantly. It is the process of pressing electrode material coated on current collector with certain pressure and it reduces its porosity and thickness. The aim of this bachelor thesis is determination of suitable level of calendaring that increases specific capacity, but does not reduce its cyclability.
Evaluation Of Temperature Influence on Lithium-ion Battery Properties
Zachová, Zuzana ; Libich, Jiří (referee) ; Bača, Petr (advisor)
This diploma thesis deals with monitoring of the influence of temperature on the properties of lithium-ion batteries, especially on the safety and capacity of selected batteries. Chapters 1 and 2 contain a literature review on the subject, describing electrochemical energy sources, especially secondary accumulators, mainly lithium-ion cells. Furthermore, the safety and degradation processes of lithium-ion batteries are discussed and the third chapter describes the design of experiments, realization and outputs of these experiments.
Study of intercalation properties of electrode materials based on expanded graphite
Vencelides, Lukáš ; Máca, Josef (referee) ; Libich, Jiří (advisor)
The diploma thesis deals with the issue of electrochemical cells and deals in detail with lithium-ion batteries. The thesis describes the history of development of lithium-ion batteries, basic information about lithium and basic types of electrochemical cells. The work is devoted in detail to the description of characteristics and operating principle of lithium-ion batteries with emphasis on the negative electrode and negative electrode materials. Of the negative electrode materials, both the most widely used material graphite and modern materials with a great potential for the future are described. In the measurement methods the work describes methods CV, GCPL and EIS. Great emphasis is placed on the explanation of the principle of the function of electrochemical impedance spectroscopy and its application in measurement of electrochemical properties of materials used in lithium-ion batteries. There is also described the procedure of calculation of diffusion coefficients using the results of electrochemical impedance spectroscopy. In the practical part, two methods are used to calculate the diffusion coefficients of lithium ions into the negative electrode made of expanded flake graphite using the results of a series of electrochemical measurements.
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.

National Repository of Grey Literature : 27 records found   1 - 10nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.