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Investigation causes of the premature capacity loss in accumulator for hybrid electric vehicles
Vystrčil, Marek ; Bilko, Radek (referee) ; Bača, Petr (advisor)
This thesis describes the results of two successive experiments. The first was focused on the influence of impurities in the active mass of negative electrode in PSoC (Partial State of Charge) mode, which simulates the conditions occurring in HEV (hybrid electric vehicle). In the second experiment, cells with the same additives were exposed to optimum downforce 4N/cm2, by which we wanted to prove the influence of pressure on life of VRLA (Valve Regulated Lead Acid) cells working in operating HEV conditions.
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Effect of glass fibers in the lead-acid batteries for hybrid electric vehicles
Klojda, Viktor ; Tošer, Pavel (referee) ; Bača, Petr (advisor)
Master´s thesis deals with the utilization of lead-acid accumulators in hybrid electric vehicle regime. It describes the side effects known as PCL, generated during PSOC regime and connected with the length of the battery lifespan. One possibility how to eliminate these effects, is the use of additives in active mass of the negative electrode, in the form of glass fibres. The project provides the parametres and reactions of additive, that have lead to the improvement of battery properties. The purpose of this thesis is to verify the positive effect of the aditive on the lifespan of the lead-acid accumulator.
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Impedance measurements of lead-acid accumulators
Vaculík, Sebastian ; Bača, Petr (referee) ; Abraham, Pavel (advisor)
The main aim of this paper is to contribute to the elucidation of electrochemical processes. These processes occur in the investigated experimental lead-acid cell. For this purpose, electrochemical impedance spectroscopy was used. There are two methods of measurement presented. First one is used to measure impedance between electrodes. Second one is used to measure impedance of collector ribs inside positive or negative electrode. The results are represented by electrical equivalent circuits, whose elements are described in detail in the theoretical part.
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Research of thermal effects in lead-acid batteries
Vrba, Marek ; Abraham, Pavel (referee) ; Neoral, Jiří (advisor)
Based on the Czech and foreign literature, this work introduces us to the history, the dividing types of electrochemical cells, specifically deals with the lead-acid battery. The lead-acid battery principle is described and its behavior during charging and discharging. Another topic is the design and distribution. The basic division is the lead-acid accumulator batteries with electrodes submerged and maintenance-free batteries so-called "VRLA", which is gradually coming into force and function of classical battery electrodes are submerged in more demanding applications. Currently, VRLA batteries are used for PSOC system in hybrid vehicles. The practical part of this work deals with PSOC regime that is applied to the experimental cells with electrodes with different admixtures. The results of the influence of admixtures on the durability of articles in PSOC system are summarized at the end of this work.
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Using lead-acid accumulators in hybrid electric vehicle regime
Klojda, Viktor ; Vaněk, Jiří (referee) ; Bača, Petr (advisor)
This bachelor´s thesis is focused on utilization of maintenance-free lead-acid accumulators in hybrid electric vehicle regime. It describes paralel and serial draft of hybrid vehicles, their function, advantages and disadvantages. It compares lead-acid accumulators with other sorts of primary, secondary and fuel cells. Purpose of this thesis is to improve the lifetime of lead-acid batteries in PSOC regime and accompanying addition use, as an activ material of negative electrode.
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Monitoring of Electrode Changes of Negative Electrode for Lead-Acid Batteries by Operando Confocal Microscopy
Hálová, Hana ; Vanýsek, Petr (referee) ; Chladil, Ladislav (advisor)
The thesis is focused on the laser microscopy observation of the negative electrode for lead-acid batteries during their cycling. The surface changes are evaluated during both deep cycling and PSoC (Partial State of Charge) cycling. The mode leads to gradual degradation of the negative electrode – mostly because of irreversible sulfation. The speed of the sulfation can be influnced by additives of the negative active mass added already during production process. The active mass was firstly examined by electron microscope and X-ray diffractometer. The crystal growth during cycling was observed using confocal microscope Olympus Lext OLS4100.
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