|
|
Aprotic electrolytes for supercapacitors
Musílek, Václav ; Knotek, Tomáš (referee) ; Dvořák, Petr (advisor)
This master´s thesis deals different types of the aprotic electrolytes for supercapacitors and investigates by impedance spectroscopy to conductivity and method cyclic voltametry to measure dimension potential windows. Used aprotic solvents: propylencarbonate, dimethylsulfoxide, N, N dimethylformamide, ethylencarbonate, dimethylcarbonate, diethylcarbonate and acetonitrile. In the aprotic solvents were appended salts: LiClO4, NaClO4, KClO4, LiBF4, LiPF6, TEABF4 and TMABF4. From these compounds were prepared solutions with the different molar concentrations.
|
|
| |
|
|
The influence of ionic liquids on functional elements in lithium-ion batteries
Meščánková, Veronika ; Sedlaříková, Marie (referee) ; Máca, Josef (advisor)
This thesis deals with ionic liquids, their conductivity and the action of the electrode materials, separators and current collectors. The theoretical part is focused on the properties of ionic liquids, Li-ion batteries, corrosion, conductivity and analysis elements. The practical part is focused on the production of graphite electrodes, measuring the conductivity of ionic liquids with different parts of lithium – ion battery and measuring the potential window. Also, there is the effect of ionic liquids described in these parts.
|
|
|
The electrical properties of modified ionic liquids
Kulhavý, Miloslav ; Libich, Jiří (referee) ; Máca, Josef (advisor)
This thesis deals with ionic liquids and use of ionic liquids as electrolytes in lithium-ion batteries. Thesis describes basic characteristics of secondary electrochemical cells and characteristics of ionic liquids. Thesis also describes modifications and measurement of ionic liquids. Thesis also presents the results of measurement conductivity and potential window of modified ionic liquids.
|
|
|
Aprotic electrolytes with fire retardant
Hlava, Kamil ; Máca, Josef (referee) ; Sedlaříková, Marie (advisor)
This thesis deals with liquid aprotic electrolytes based on sulfolane with added flame retardant. The theoretical part of the thesis explains concepts - mainly aprotic electrolytes, flame retardants, and their practical use. It also discusses lithium - ion accumulators and materials used in them while focusing on the electrolyte function. The practical part of the thesis aims to measure the properties of aprotic electrolytes: their conductivity, potential window and flashpoint. It also contains a review of the measurement results.
|
|
|
The width of potential window of boron doped diamond electrodes in dependence on their pretreatment and composition of the mixed electrolyte solution
Dvořáková, Klára ; Schwarzová, Karolina (advisor) ; Dejmková, Hana (referee)
The diploma thesis focuses on the range of the potential window of the BDD electrode in dependence on the composition of the mixed electrolyte solution and the treatment of the electrode surface. The measurements were performed on a polished (p-BDD) and O-terminated (O-BDD) electrode by the method of linear sweep voltammetry (LSV) in a three-electrode system. It was confirmed that in an environment with a suitable organic solvent, the range of the potential window widens. The measured solutions consisted of deionized water containing sodium perchlorate with a concentration of 1 mmol l−1 and one organic solvent in which sodium perchlorate with a concentration of 1 mmol l−1 was also dissolved. Acetonitrile, methanol, N,N-dimethylformamide and isopropanol were used in solutions (0 %, 1 %, 5 %, 10 %, 50 %, 70 %, 90 %, 95 %, 99 % or 100 % volume percent). Expansion, or the shortening of the potential window range was evaluated separately for each solvent in the anodic and cathodic regions. The expansion of the window on both sides was confirmed in acetonitrile as the concentration of the solvent increases, so it is based on this experiment as a universal solvent suitable for the determination of reducing and oxidizing analytes, from measurements on O-BDD and also on p-BDD. In the case of the remaining...
|
|
|
Gel Polymer Electrolytes Based On MMA With Ionic Liquids
Jahn, Michal
Gel polymer electrolytes are perspective electrolytes for new types of Li-ion batteries today. The properties respectively advantages of these gels can be used also in other fields of electrochemistry. Very promising combination can be electrochemically stable polymers and ionic liquids, which are substances that consist of an organic cation and an inorganic or organic anion, with a melting point below 100 °C. Main advantages of ionic liquids are high ionic conductivity, inflammability and excellent electrochemical stability. These ionic liquids may be suitable for new lithiumion batteries and supercapacitors, especially where the required higher thermal stability. In this paper, I will present fundamental characteristics of gel polymer electrolytes with ionic liquids.
|
|
|
The influence of ionic liquids on functional elements in lithium-ion batteries
Meščánková, Veronika ; Sedlaříková, Marie (referee) ; Máca, Josef (advisor)
This thesis deals with ionic liquids, their conductivity and the action of the electrode materials, separators and current collectors. The theoretical part is focused on the properties of ionic liquids, Li-ion batteries, corrosion, conductivity and analysis elements. The practical part is focused on the production of graphite electrodes, measuring the conductivity of ionic liquids with different parts of lithium – ion battery and measuring the potential window. Also, there is the effect of ionic liquids described in these parts.
|
|
|
The electrical properties of modified ionic liquids
Kulhavý, Miloslav ; Libich, Jiří (referee) ; Máca, Josef (advisor)
This thesis deals with ionic liquids and use of ionic liquids as electrolytes in lithium-ion batteries. Thesis describes basic characteristics of secondary electrochemical cells and characteristics of ionic liquids. Thesis also describes modifications and measurement of ionic liquids. Thesis also presents the results of measurement conductivity and potential window of modified ionic liquids.
|
|
|
Aprotic electrolytes with fire retardant
Hlava, Kamil ; Máca, Josef (referee) ; Sedlaříková, Marie (advisor)
This thesis deals with liquid aprotic electrolytes based on sulfolane with added flame retardant. The theoretical part of the thesis explains concepts - mainly aprotic electrolytes, flame retardants, and their practical use. It also discusses lithium - ion accumulators and materials used in them while focusing on the electrolyte function. The practical part of the thesis aims to measure the properties of aprotic electrolytes: their conductivity, potential window and flashpoint. It also contains a review of the measurement results.
|
guest ::
