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Study of the properties of the advanced materials for the cathodes of the lithium-ion accumulators
Pustowka, Pavel ; Tichý, Jiří (referee) ; Kazda, Tomáš (advisor)
This thesis in its first part deals especially with characteristic of lithium ion accumulators in terms of their structure, electrochemical properties and also features of the most commonly used cathode materials. Especial attention is given to the high-voltage cathode material LiNi0,5Mn1,5O4 which cell voltage is close to 5V. The second practical part deals with the preparation of cathode materials based on LiNi0,5Mn1,5O4 with different temperatures in the second stage of annealing and analyzing them in terms of structure and electrochemical properties using appropriate measuring methods.
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Determination of the most suitable ratio of cathode materials for the lithium-sulfur battery system
Benešová, Petra ; Kazda, Tomáš (referee) ; Jaššo, Kamil (advisor)
This master's thesis deals with a topic of determination of the most suitable ratio of cathode materials for the lithium-sulfur systems. The first two chapters provide a general introduction to the topic of electrochemical energy sources and present the commonly used primary and secondary battery systems with emphasis on their characteristics and applications. The core of the theoretical part is dedicated to lithium-ion and lithium-sulfur batteries, their working principles along with the benefits or drawbacks related to the particular systems, and widely used materials. The experimental part briefly comments on determining the suitable electrode paste preparation method, the subsequent main part is focused on evaluation of electrochemical performance of cells using different ratios of cathode materials. Five samples of cathode materials were prepared, where the sulfur ratio is in range from 64 to 88 wt. %. Finally, the comparison of all prepared ratios in terms of their electrochemical properties is provided.
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Electrode materials and electrolytes for aluminium-ion accumulators
Benešová, Petra ; Kazda, Tomáš (referee) ; Čech, Ondřej (advisor)
This bachelor thesis presents a topic of aluminum-ion batteries, which have recently attracted great attention owing to their good electrochemical performance and possible use in commercially produced electronics. The paper introduces the basic principles of the function of aluminum-ion accumulators and their advantages, which are a main motivation for further research. The main feature of the theoretical part is an overview of the current state of research on suitable electrode materials and electrolytes for this type of accumulators. The experimental part is focused on the preparation of several carbon-based cathode materials, preparation of the IL-type electrolyte and subsequent cell assembly. The obtained results are evaluated and briefly discussed, taking into account the effects of the cell components and other factors.
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Study of the electrode materials for Li-Ion accumulators by electron microscopy
Kaplenko, Oleksii ; Čudek, Pavel (referee) ; Kazda, Tomáš (advisor)
The aim of this work is to describe the influence of temperature on the structure and chemical composition of electrode materials for Li-ion accumulators. Theoretical part of this thesis contains described terminology and general issues of batteries and their division. Every kind of battery is provided with a closer description of a specific battery type. A separate chapter is dedicated to lithium cells, mainly Li-ion batteries. Considering various composition of Li-ion batteries, the next subchapters deeply analyzes the most used cathode (with an emphasis on the LiFePO4, LiMn1/3Ni1/3Co1/3O2) and anode materials (with an emphasis on the Li4Ti5O12). The next chapters describe the used analytical methods: electron microscopy, energy dispersion spectroscopy and thermomechanical analysis. The practical part is devoted to the description of the individual experiments and the achieved results.
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Determination Of The Most Suitable Ratio Of Cathode Materials For The Lithium-Sulfur Battery System
Benešová, Petra
This paper presents the topic of lithium-sulfur batteries with a main focus on the influenceof different ratio of the cathode materials on the final electrochemical performance of the cell.The theoretical part of the article provides a comprehensive overview of the Li-S technology, mainadvantages and challenges related to the practical use of Li-S systems, and briefly mentions thetypical cathode materials. The objective of the experimental part is to provide a comparison of differentratios of cathode materials in terms of their electrochemical performance, taking into considerationthe physicochemical properties of prepared materials.
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Determination of the most suitable ratio of cathode materials for the lithium-sulfur battery system
Benešová, Petra ; Kazda, Tomáš (referee) ; Jaššo, Kamil (advisor)
This master's thesis deals with a topic of determination of the most suitable ratio of cathode materials for the lithium-sulfur systems. The first two chapters provide a general introduction to the topic of electrochemical energy sources and present the commonly used primary and secondary battery systems with emphasis on their characteristics and applications. The core of the theoretical part is dedicated to lithium-ion and lithium-sulfur batteries, their working principles along with the benefits or drawbacks related to the particular systems, and widely used materials. The experimental part briefly comments on determining the suitable electrode paste preparation method, the subsequent main part is focused on evaluation of electrochemical performance of cells using different ratios of cathode materials. Five samples of cathode materials were prepared, where the sulfur ratio is in range from 64 to 88 wt. %. Finally, the comparison of all prepared ratios in terms of their electrochemical properties is provided.
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Study Of The Electrode Materials For Li-Ion
Accumulators By Electron Microscopy
Kaplenko, Oleksii
One of the biggest problems with current Li-Ion batteries is thermal stability. Some active materials are more stable than others, but usually high-capacity materials suffer from lower thermal stability. During heating, not only the decomposition of the cathode material, but also the decomposition of other parts of the accumulator, such as anode material, binders and electrolytes, occurs. One of the important advantages of LiFePO4 over other cathode materials is its thermal and chemical stability, which improves battery safety. For this reason, high temperature effects were monitored on individual parts of the complete electrode, and the results are described in this work.
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Electrode Materials And Electrolytes For
Aluminum-Ion Accumulators
Benešová, Petra
This article presents the topic of aluminum-ion batteries, which may become an available alternative to commercially used lithium-ion batteries. Theoretical part of the paper focuses on the basic principles of aluminum-ion accumulators, their advantages in comparison with lithium-ion batteries, and the current state of research on electrode materials and electrolytes for Al-ion batteries. The experimental part deals with preparation of carbon based cathode material, ionic liquid electrolyte
and subsequent assembly of the electrode cell. Basic measurements were made to verify the electrochemical activity of the assembled cell. Eventually, the obtained results and following procedures or process modifications are discussed.
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Electrode materials and electrolytes for aluminium-ion accumulators
Benešová, Petra ; Kazda, Tomáš (referee) ; Čech, Ondřej (advisor)
This bachelor thesis presents a topic of aluminum-ion batteries, which have recently attracted great attention owing to their good electrochemical performance and possible use in commercially produced electronics. The paper introduces the basic principles of the function of aluminum-ion accumulators and their advantages, which are a main motivation for further research. The main feature of the theoretical part is an overview of the current state of research on suitable electrode materials and electrolytes for this type of accumulators. The experimental part is focused on the preparation of several carbon-based cathode materials, preparation of the IL-type electrolyte and subsequent cell assembly. The obtained results are evaluated and briefly discussed, taking into account the effects of the cell components and other factors.
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