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Negative lead-acid battery electrode for hybrid electric vehicles
Dvořáček, Daniel ; Křivík, Petr (referee) ; Bača, Petr (advisor)
The thesis briefly discusses the issue of electrochemical power sources, especially with a focus on lead-acid batteries operating in modes that are typical of hybrid electric vehicles. The theoretical part of the thesis should be a good basis for the subsequent practical part, in which several experimental electrodes and their parameters will be performed and evaluated. The output of the practical part will be conclusions regarding the influence of different variants of modified carbon used as an additive in the active material of the negative electrode on the capacity and life of cells
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Negative lead electrode for hybrid electric vehicles
Opravil, Petr ; Zimáková, Jana (referee) ; Bača, Petr (advisor)
This bachelors thesis is focusing on degradational proceses occurring in electrodes of lead-acid batteries working in parcial state of charge used in hybrid electric vehicles. Studied topics include storage of electrical energy, hybrid powertrains and lead-acid accumulators. Experimental cells have been made and were later used in experiments maintaining partial state of charge. This work is focused on finding a link between silanized glass fibres added to the electrodes and lowering the amount of degradation of cells.
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Application of Ultracapacitors in Traffic Systems
Kalina, Emil ; Vorel, Pavel (advisor)
The work deals with relatively new components allowing electric energy accumulation – ultracapacitors. It focuses on their application in traffic systems – in independent electric vehicles. Design and verification of a system with ultracapacitor and DC/DC adaptive converter was done. Control of the adaptive converter modifies very positively the time wafeform of the traction accumulator current during the drive cycle. The designed connection of ultracapacitor and DC/DC converter implemented in the drive structure of experimental electric vehicle with induction machine contributes to increment the action radius of the vehicle by 16% (determined by experimental verification). This result was achived particularly by limitation of traction accumulator current peaks, And by more effective storage of energy gained by recuperative braking of the vehicle as well. The core of the system is a control of the adaptive converter in order to provide an active filtration of the accumulator’s current to its long-period mean value, i.e. elimination of current (power) peaks. These are caused by acceleration from non-zero initial vehicle speed or by recuperative braking. This is done by a subsidiary current loop. The converter has a superior voltage regulation loop, which sets in long-time period the voltage of ultracapacitors to the proper value – indirectly dependent on the speed of the vehicle. This ensures the appropriate energy management of the ultracapacitor. In the following, properties of test set of ultracapacitors were verified. Finally, methods of suppression of capacity variability influence in series connection of these components were compiled and critically reviewed.
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Negative lead electrode for hybrid electric vehicles
Opravil, Petr ; Zimáková, Jana (referee) ; Bača, Petr (advisor)
This bachelors thesis is focusing on degradational proceses occurring in electrodes of lead-acid batteries working in parcial state of charge used in hybrid electric vehicles. Studied topics include storage of electrical energy, hybrid powertrains and lead-acid accumulators. Experimental cells have been made and were later used in experiments maintaining partial state of charge. This work is focused on finding a link between silanized glass fibres added to the electrodes and lowering the amount of degradation of cells.
|
|
|
Negative lead-acid battery electrode for hybrid electric vehicles
Dvořáček, Daniel ; Křivík, Petr (referee) ; Bača, Petr (advisor)
The thesis briefly discusses the issue of electrochemical power sources, especially with a focus on lead-acid batteries operating in modes that are typical of hybrid electric vehicles. The theoretical part of the thesis should be a good basis for the subsequent practical part, in which several experimental electrodes and their parameters will be performed and evaluated. The output of the practical part will be conclusions regarding the influence of different variants of modified carbon used as an additive in the active material of the negative electrode on the capacity and life of cells
|
|
|
Application of Ultracapacitors in Traffic Systems
Kalina, Emil ; Vorel, Pavel (advisor)
The work deals with relatively new components allowing electric energy accumulation – ultracapacitors. It focuses on their application in traffic systems – in independent electric vehicles. Design and verification of a system with ultracapacitor and DC/DC adaptive converter was done. Control of the adaptive converter modifies very positively the time wafeform of the traction accumulator current during the drive cycle. The designed connection of ultracapacitor and DC/DC converter implemented in the drive structure of experimental electric vehicle with induction machine contributes to increment the action radius of the vehicle by 16% (determined by experimental verification). This result was achived particularly by limitation of traction accumulator current peaks, And by more effective storage of energy gained by recuperative braking of the vehicle as well. The core of the system is a control of the adaptive converter in order to provide an active filtration of the accumulator’s current to its long-period mean value, i.e. elimination of current (power) peaks. These are caused by acceleration from non-zero initial vehicle speed or by recuperative braking. This is done by a subsidiary current loop. The converter has a superior voltage regulation loop, which sets in long-time period the voltage of ultracapacitors to the proper value – indirectly dependent on the speed of the vehicle. This ensures the appropriate energy management of the ultracapacitor. In the following, properties of test set of ultracapacitors were verified. Finally, methods of suppression of capacity variability influence in series connection of these components were compiled and critically reviewed.
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