|
| |
|
|
Effect of additives in lead-acid batteries for hybrid electric vehicles
Tobolák, Jakub ; Křivík, Petr (referee) ; Bača, Petr (advisor)
This thesis is focused on lead-acid batteries used in hybrid electric vehicles. These batteries operate under partial charge, which brings problems with premature capacity loss. Tasks is to examine the influence of glass fibers as possible additives to the negative electrode of these cells in order to extend their life. The text describes the problem of hybrid electric vehicles, lead-acid batteries and other electrochemical sources.
|
|
|
Modified glass fibers as additives of the negative electrode of a lead-acid battery
Zbožínek, Tadeáš ; Zimáková, Jana (referee) ; Bača, Petr (advisor)
This bachelor thesis is focused on the working of lead-acid batteries in hybrid electronic vehicles. The goal is to increase the negative electrode characteristics of VRLA batteries. The negative electrode suffers significant degradation in the partial-state-of-charge mode, which is used for these vehicles. When the VRLA battery is being used in the partial-state-of-charge mode, premature loss of capacity occurs due to sulfation of the negative active mass. For these reasons we are trying to improve active mass with additives, which Is expected to interrupt the unwanted processes, that leading to capacity loss. We are focusing on a specific additive in form of glass fibers, which exhibits similar positive effect on the lifetime of the battery as a carbon additive. The surface of glass fibers will be modified. Afterwards, the influence of the modified glass fibers on the lifetime of the battery will be observed.
|
|
|
Modified glass fibers as additives of the negative electrode of a lead-acid battery
Zbožínek, Tadeáš ; Zimáková, Jana (referee) ; Bača, Petr (advisor)
This bachelor thesis is focused on the working of lead-acid batteries in hybrid electronic vehicles. The goal is to increase the negative electrode characteristics of VRLA batteries. The negative electrode suffers significant degradation in the partial-state-of-charge mode, which is used for these vehicles. When the VRLA battery is being used in the partial-state-of-charge mode, premature loss of capacity occurs due to sulfation of the negative active mass. For these reasons we are trying to improve active mass with additives, which Is expected to interrupt the unwanted processes, that leading to capacity loss. We are focusing on a specific additive in form of glass fibers, which exhibits similar positive effect on the lifetime of the battery as a carbon additive. The surface of glass fibers will be modified. Afterwards, the influence of the modified glass fibers on the lifetime of the battery will be observed.
|
|
|
Evaluation Of Temperature Influence on Lead-Acid Battery Properties
Langer, Martin ; Zimáková, Jana (referee) ; Bača, Petr (advisor)
This work deals with lead-acid batteries, their properties and individual types that are available on the market. The temperature dependences of the battery parameters at different ambient temperatures and at different discharging and charging modes are measured here. The theoretical part of the work deals with electrochemical cells in general, description of their main parts and principles of operation. The work analyzes the types of batteries used, their advantages and negatives. In the case of a lead-acid battery, its internal structure and the function of the electrodes and the electrolyte are taken into account. Furthermore, a description of individual possible negative phenomena that take place in lead-acid batteries and contribute to the end of their service life is included. In the practical part, 6 batteries are tested at different charging currents, which provides information about their behavior both during discharge and at the time of charging. During the experiments, testing is not only performed at room temperature, but the batteries are also exposed to high temperatures up to 75 ° C.
|
|
|
Cycling Of Vrla Lead-Acid Batteries For Use In Uninterruptible Power Supplies And Measurement Of Failed Batteries
Musil, Petr
This article deals with study on the influence of cycling of batteries with regard to their parameters. Electro-chemical reactions which take part in battery cells are described. This paper also offers a measurement scheme for automated measuring workstation. Furthermore, results of measurements are being presented on measured parameters of chosen batteries. Comparison of the measurements results and datasheet values is included. Conclusion sums up parameters of chosen batteries and their feasibility for further usage in Uninterruptible Power Supply as a crucial part of critical infrastructure.
|
|
|
The examination of the effect of titanium dioxide on the properties of lead-acid batteries
Mlýnek, Martin ; Vaněk, Jiří (referee) ; Bača, Petr (advisor)
Despite, considerable advances in technologies for storing electrical energy, lead-acid batteries are still the most widely used these days even it was invented more than a century ago. The functionality remains the same since its invention. Today´s time puts certain pressure on improving some aspects of the functionality like, heat management, charging and discharging speed, capacity and durability etc..... This bachelor´s thesis is based on the last mentioned, Durability,. The work presents the theory of acid batteries with the history of chemical reaction, technological production processes and battery construction. It is followed by a chapter about titanium and titanium dioxide as an addition of negative active mass where all the aspects are being examined in this work.
|
|
|
The examination of the effect of titanium dioxide on the properties of lead-acid batteries
Mlýnek, Martin ; Vaněk, Jiří (referee) ; Bača, Petr (advisor)
Despite, considerable advances in technologies for storing electrical energy, lead-acid batteries are still the most widely used these days even it was invented more than a century ago. The functionality remains the same since its invention. Today´s time puts certain pressure on improving some aspects of the functionality like, heat management, charging and discharging speed, capacity and durability etc..... This bachelor´s thesis is based on the last mentioned, Durability,. The work presents the theory of acid batteries with the history of chemical reaction, technological production processes and battery construction. It is followed by a chapter about titanium and titanium dioxide as an addition of negative active mass where all the aspects are being examined in this work.
|
|
|
Effect of additives in lead-acid batteries for hybrid electric vehicles
Tobolák, Jakub ; Křivík, Petr (referee) ; Bača, Petr (advisor)
This thesis is focused on lead-acid batteries used in hybrid electric vehicles. These batteries operate under partial charge, which brings problems with premature capacity loss. Tasks is to examine the influence of glass fibers as possible additives to the negative electrode of these cells in order to extend their life. The text describes the problem of hybrid electric vehicles, lead-acid batteries and other electrochemical sources.
|
|
|
Causes of Premature Capacity Loss of Lead-Acid Accumulators Operating in PSoC Mode in Hybrid Electric Vehicles
Bilko, Radek ; Jareš, Petr (referee) ; Dostál, Zdeněk (referee) ; Bača, Petr (advisor)
This thesis is completion of whole stage of researches and it is a result of existing need of increase efficiency, utilization rate and service life of lead acid batteries VRLA planned for utilization in hybrid electric vehicles in mode of partial state-of-charge PSoC. During the application of mode PSoC at lead acid battery occurs irreversible sulfation of negative electrodes and thus to loss their charging capability. This phenomenon, according to the latest trend called PCL3, isn´t connected with subsequently referred effects PCL1, PCL2, show up on positive electrodes. Result of this thesis is finding a new types of additives, determine their optimum amount and size in such a way that innovated composition of negative active materials be able to resist sulfation of negative electrode during operation in mode PSoC. Part of the effort to clarify actions ongoing on negative active material and causes non-returnable sulfation electrodes is also monitoring of structural changes electrode active material by using environmental scanning electron microscope, which helped to clarify processes related with loss of capacity in mode PSoC. Special attention during reserches was focused on study of the properties contact layers between collector and electrodes active material and itself active materials lead-acid battery druring exploitation. There were gain new information about influence repeated cycling of (charging, discharging) the critical area of the electrodes. Measurements was carried out on specially prepared experimental electrodes DC Difference Method, this enabled obtain data in situ.
|
guest ::
