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11	Vliv teploty na životnost olověného akumulátoru / Influence of temperature on lead acid batteries lifetime Kopečný, Martin January 2011 (has links) Lead –acid batteries are the most common type of secondary cells used in automotive industry. This diploma thesis deals with the influence of temperature on their lifetime. In the preamble of this work is shortly described their history, division, construction and processes during battery operation. There are noted unfavorable phenomena which have an impact on increasing the temperature inside the battery. The first experimental part is devoted to evaluation the effects of addition on the temperature rise during charging. The second part is focused on conditions simulation in hot areas at the temperature above 30 °C and effects of this temperature on the function of lead – acid batteries.
12	Impedanční měření olověného akumulátoru / Impedance Measurement of Lead-acid Accumulator Abraham, Pavel January 2013 (has links) This dissertation deals with impedance measurements of lead-acid accumulator. Main aim was to study recent problems of impedance measurements of lead-acid accumulator and most importantly to extend difference method and also to interpret its results. The original DC difference method was developed earlier at our Power Sources Laboratory of Department of Electrical and Electronic Technology. The DC difference method and also the new AC difference method are both non-destructive, which means that experimental data can be obtained in situ. New method provides more accurate set of information because of its wide frequency range nature. Electrodes of lead-acid accumulator were analysed with special attention to collector / active mass double layer and to active mass itself. Various states and operation regimes were investigated. Obtained data contributed to better understanding of involved degradation mechanisms. Main aim of other experiment was to observe and interpret corrosion rates of electrode collector composed of various lead alloys. Last but not least charge and discharge regimes e.g. 100% deep of discharge regime, partial state of charge (PSoC) regime and pulse charge regime were analysed. BioLogic VSP was the device used for almost all experimental measurements. It takes a lot of effort to optimise VSP operation regime. Best operation regime of VSP for the difference method was suggested too.
13	Příčiny předčasné ztráty kapacity olověných akumulátorů pracujících v PSoC režimu hybridních elektrických vozidel / Causes of Premature Capacity Loss of Lead-Acid Accumulators Operating in PSoC Mode in Hybrid Electric Vehicles Bilko, Radek January 2014 (has links) 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.
14	Fabrication et caractérisation de détecteurs à gouttelettes en surchauffe à bas bruit de fond au sein du projet PICASSO Piro, Marie-Cécile January 2008 (has links) Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal. Matière sombre Supersymétrie WIMP Détecteur de gouttelettes en surchauffe Polymérisation Salle blanche Nucléation Test d'étalonnage Masse active Mesure de bruit de fond Analyse des signaux Neutrons Émetteurs [alpha] Purification des matériaux SNOLAB Dark matter Supersymmetry WIMP Superheated droplet detector Polymerization Clean room Nucleation Calibration measurements Active mass Background measurements Signal analysis Neutrons [Alpha] emitters Purification of materials SNOLAB
15	Fabrication et caractérisation de détecteurs à gouttelettes en surchauffe à bas bruit de fond au sein du projet PICASSO Piro, Marie-Cécile January 2008 (has links) Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal Matière sombre Supersymétrie WIMP Détecteur de gouttelettes en surchauffe Polymérisation Salle blanche Nucléation Test d'étalonnage Masse active Mesure de bruit de fond Analyse des signaux Neutrons Émetteurs [alpha] Purification des matériaux SNOLAB Dark matter Supersymmetry WIMP Superheated droplet detector Polymerization Clean room Nucleation Calibration measurements Active mass Background measurements Signal analysis Neutrons [Alpha] emitters Purification of materials SNOLAB

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