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Modification Of The Production Of Positive Electrodes For Lithium-Sulfur Batteries
Jaššo, Kamil
The rapid development of electrical wearable devices and electric cars is forcing battery industry into developing more efficient and economic energy storage systems. One of the attractive candidates among these systems are Li-S batteries. These next-generation high-energy rechargeable batteries are promising mainly thanks to their high theoretical energy density and low cost. However, the safety concerns of lithium anode, insulating properties of sulfur and rapid drop of capacity during cycling due to dissolution of polysulfides are key limitations of practical use. A cell composed of metal lithium anode and carbon doped sulfur cathode in environment of *LiTFSI:LiNO3 DME:DOL electrolyte can be considered a basic lithium-sulfur cell. This type of lithium-sulfur cell is used in many scientific publications. This paper discusses the production of positive electrodes for lithiumsulfur cells and modifications of their production.
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Li-Ion Accumulators – Comparison Of Cathode Materials
Lexová, Kristýna
The issue of energy storage becomes increasingly important with the growing need for safe and clean energy that could be used in portable electronics and electric vehicles. This paper shortly introduces the topic of lithium-ion accumulators, compares currently used cathode materials and discusses promising future materials.
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Influence Of Ambient Temperature On Electrochemical Parameters Of Lithium-Sulfur Batteries
Jaššo, Kamil
With the increasing popularity of electric vehicles, the demand for their range is increasing and thus demand for the batteries that power them. Range of current electric vehicles using Li-ion battery technology is around 250 miles (400 km). In the case of use of new prospective next-gen batteries such as Lithium-sulfur (Li-S) range of the electric vehicle may be doubled or even tripled. However, there are many challenges ahead of using these batteries in electric vehicles. Since the batteries in electric vehicles are largely affected by ambient temperature, this article deals with researching the effect of ambient temperature on lithium-sulfur batteries.
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Influence Of Ambient Atmosphere To Active Material Of Disassembled Li-Ion Accumulator
Karmazinova, Katerina
At the present time the worldwide hot topic is recycling. How to deal with the product at the end of its life cycle? This paper is focused on recycling of active cathode material of lithiumion accumulators. The research considers the influence of ambient atmosphere on different types of lithium-ion accumulators within a time period. As the recycling method was chosen the solvent extraction. The results show a comparison of two the most common used cathode materials for lithium-ion accumulators – LiCoO2 and LiMn1/3Ni1/3Co1/3O2. At the forefront is the time period from disassembly the lithium-ion accumulator to extract cathode active material without structure changes due to the effect of the air atmosphere.
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Effect of temperature on electrochemical parameters of Li-S battery
Bečan, Jan ; Skala, Kateřina (referee) ; Jaššo, Kamil (advisor)
This bachelor's thesis deals with the production of lithium-sulfur battery and the effect of changing temperatures on its electrochemical parameters. The theoretical part is focused on primary and secondary batteries and their historical evolution, anode and cathode materials for lithium-ion batteries and next-generation batteries. The practical part is focused on preparing the electrode material for lithium-sulfur battery, completion of electrochemical cell and measuring the values of cycling charge/discharge at different temperatures.
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Carboxymethyl Cellulose As The Binder For
The Lithium-Sulfur Batteries
Jaššo, Kamil
Demand for the high energy density batteries significantly increased along with the rapid development of new power source depending technologies. While these technologies are rapidly evolving, the battery industry is lagging behind unable to meet the demand. As a prospective successor to the existing li-ion battery technology, can be the high-capacity lithium-sulfur battery system (Li-S). The most commonly used composition of the positive electrode material of Li-S batteries is a mixture of sulfur, carbon and PVDF1 binder mixed in NMP2 solvent, which is (according to the WHO3) slightly toxic. The article deals with a replacing PVDF with organic non-toxic water-soluble binder.
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Advanced systems of Li-Ion accumulators
Lexová, Kristýna ; Langerová, Petra (referee) ; Mihai, Hana (advisor)
S rostoucí potřebou energie pro přenosnou elektroniku a elektrická vozidla se problematika úschovy elektrické energie stává stále významnější. Tato bakalářská práce poskytuje přehled elektrochemických zdrojů energie, a to zejména lithno-iontových akumulátorů a nejpoužívanějších materiálů pro kladnou elektrodu. Práce pojednává také o vývoji vysokonapěťových katodových materiálů, včetně systému lithium-síra. Experimentální část této práce popisuje zhotovení několika vzorků kladných elektrod, a porovnává jejich elektrochemické vlastnosti.
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Design and properties of low-frequency amplifier with vacuum valves
Piroha, Ladislav ; Musil, Vladislav (referee) ; Šandera, Josef (advisor)
The purpose of the bachelor’s thesis is explanation of theory and construction of low frequency tube audio amplifier with UV meter. Main focus is on history and development of vacuum circuits from its early beginning, on electrical parameters and applied physical principles. Explanation of operating characteristics of amplifier classes and comparison of vacuum tube sound acoustic performance against transistor amplifier one. Finally, there is build description of single ended amplifier class A.
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Study of stability of electrolytes and electrodes by electrochemical methods
Bukáčková, Ivana ; Čech, Ondřej (referee) ; Kazda, Tomáš (advisor)
This master´s thesis deals with stability of electrolytes and electrodes using electrochemical methods of Li-ion batteries. The first part of the project is devoted to the characteristics of Li-ion batteries, electrochemical reactions and characteristics of electrode materials. Consenquetial part is concentrated on preparation and measurement of elektrolyte EC : DMC with 1M LiPF6. The elektrolyte was investigated using galvanostatic method, cyclic voltammetry and impedance spectroscopy.
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