Orientador: Eduardo René Perez Gonzalez / Banca: Carlos Frederico de Oliveira Graeff / Banca: Valtencir Zucolotto / O Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi da Unesp / Resumo: Na presente dissertação de mestrado apresentam-se estudos de um material polimérico do tipo poli(azo)uretana, chamada aqui de PAzoU, obtida a partir da reação de azocorante com o bis-carbonato cíclico de di-glicidiléter-bis-fenol A. A reação do azocorante possuindo dois agrupamentos 'NH IND. 2' livres com o bis-carbonato conduz à formação da PAzoU, a qual foi caracterizada por ressonância magnética nuclear de carbono 13 ('INTPOT. 13 C' RMN) em solução e na forma de pó e cromatografia de permeação por gel (GPC). Vale ressaltar a importância ecológica e industrial deste processo, uma vez que a poliuretana resultante é livre de isocianato (NIPU, do inglês non-isocyanate polyurethane) e foi obtida a partir da captura e ativação do 'CO IND. 2'. Uma vez caracterizado o polímero, filmes nanoestruturados foram fabricados com o objetivo principal de se investigar a estruturação em nível molecular do polímero nos filmes finos. Tal estruturação, além das características físicas e químicas do material em si, é um fator fundamental nas propriedades óticas e elétricas do filme. A importância do estudo destes materiais na forma de filmes finos justifica-se porque a maioria dos dispositivos eletrônicos de materiais orgânicos é fabricada tendo o filme fino como elemento transdutor de sinal. Três diferentes tipos de filmes finos foram estudados: filmes de Langmuir, filmes de Langmuir-Blodgett (LB) e filmes evaporados (ou PVD, do inglês physical vapor deposition). Os filmes de Langmuir, estudados na forma de monocamadas na interface ar/água, foram caracterizados por isotermas de pressão de superfície vs área molecular média (isotermas 'pi'-A) variando-se diferentes parâmetros: solventes para a dissolução do polímero, testes de estabilidade, curvas de histereses, velocidade de compressão das moléculas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work is related to the results of the study of a polymeric material in a form of ultrathin films. The studied polymer is a poly(azo)urethane, named PAzoU, obtained by the copolymerization of a diazo(4-aminomethyl-benzylamine) with the cyclic bis-carbonate of diglicidilether- bis-phenol A. The final polyurethane is a NIPU, non-isocyanate polyurethane material being remarkable the ecological and industrial role of materials obtained from 'CO IND. 2' capture and activation. The PAzoU was characterized by carbon 13 nuclear magnetic resonance ('INTPOT. 13 C' RMN) in solution and in solid state, and by gel permeation chromatography (GPC). Once the polymer was characterized, nanostructured films were fabricated for investigating the polymer structuration at molecular level. Such structuration, in addition to the physical and chemical characteristics of the material itself, plays an important role on the film optical and electrical properties. In fact, most of the organic electronic devices are fabricated with the signal transducer element as a thin film. This justifies the importance of the study of the polymeric materials in the thin film form. The films have been studied in the monomolecular form by the langmuir technique on the air/water interface. The PAzoU has been characterized by isotherms of surface pressure vs mean molecular area ('pi'-A isotherm). The influence of the solvent has been investigated and N,N-dimethylformamide (DMF) was chosen as the most appropriate for 'pi'-A isotherm experiments. Hence, other experiments were carried out using DMF as solvent: stability tests, hysteresis curves, compression speed of the molecules, and mixed films produced using stearic acid (SA). Afterwards the Langmuir films were transferred onto solid substrate forming Langmuir-Blodgett (LB) films, which were... (Complete abstract click electronic access below) / Mestre

Orientador: Celia Marina de Alvarenga Freire / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-28T23:57:37Z (GMT). No. of bitstreams: 1 Silva_JoseRochaAndradeda_M.pdf: 3642803 bytes, checksum: e91a23ef6d38a032df085e07b32843f1 (MD5) Previous issue date: 2000 / Resumo: Os acumuladores de energia estacionários devem ser periodicamente avaliados quanto à sua capacidade de carga, visando assegurar que sua energia acumulada poderá ser prontamente utilizada, quando das falhas do sistema de alimentação convencional. Normalmente, essas avaliações são realizadas através dos testes de capacidade, que apresentam como principais desvantagens, o fato do banco de baterias permanecer indisponível, durante a realização do teste, e o desperdício da energia acumulada nas baterias. Neste trabalho á avaliada a potencialidade do método de espectroscopia de impedância eletroquímica como ferramenta na determinação do estado-de-carga de baterias chumbo-ácidas, através da análise das relações dos seus parâmetros eletroquímicos e sua quantidade de carga armazenada / Abstract: Stationary lead-acid batteries must have their charge capacity periodically evaluated in order to assure that they are ready to supply energy during conventional supplier faults. Normally, these evaluations are conduct by capacity tests, which present these main disadvantages: batteries remain unavailable while tests are conducted and total energy accumulated in batteries is dissipate during the tests. In this work electrochemical impedance spectroscopy is evaluated as a tool to assess the lead., acid batteries¿ state-of-charge, by analysing the co-relations between battery electrochemical parameters and its stored energy / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

One of the technical advances made by the lead-acid battery industry in the field of portable power supply was the development of the valve regulated lead-acid battery (VRLA). This battery reduced the necessity for periodic servicing in terms of having to replenish the cells with distilled water. Further, this new type of battery can now be installed near sensitive electronic equipment without the danger of acid spill or dangerous fumes being emitted. In addition, longer service performance is achieved in terms of life cycle capacity, when compared to the conventional flooded type batteries. However, the new type of battery requires the manufacturing of high precision electrodes and components with low tolerances for error. In order for the manufacturers to produce such a premium product, a thorough understanding of the electrochemistry of the inner components is necessary. None of the South African lead-acid battery manufacturers are currently making VRLA batteries to supply a very competitive global market, where a large range of sizes and capabilities are available. In order to introduce the VRLA battery into such a competing market in South Africa, a niche area for its application was identified in order to establish the viability of manufacturing such a battery locally. This is done by integrating the VRLA concept into an existing battery, such as the miners cap lamp (MCL) battery. Its application is specific with well-defined performance criteria in a relatively large consumable market in the South African mining industry. The study looked at various components within a local manufacturing environment that required a better understanding and modification of the processes to build VRLA MCL batteries. This included a detailed study of the manufacturing processes of the positive electrode. The study involved the investigation of the types of grid alloys used, the type of electrode design, such as tubular or flat plate, the addition of redlead to the paste mixing process and subjecting the batteries to accelerated life cycle testing. A better understanding of the oxygen recombination cycle was also performed in order to evaluate the correct use of certain design criteria in the manufacturing process. This included the study of the pressure release valve and the type of positive electrode used. The study also looked at developing an inexpensive analytical technique to evaluate the porosity of cured and formed electrodes using a glycerol displacement method. The monitoring of the state of health (SoH) of VRLA batteries on a continuous basis is an important parameter in unique applications such as remote power supply. A device was developed to monitor the SoH of VRLA batteries on a continuous basis. The working principle of the device was tested on a MCL VRLA battery. With the development of other types of VRLA batteries for specific applications such as in stand-by power supplies, the monitoring device would then be integrated in the battery design.

In this paper, a state of charge (SOC) and a state of health (SOH) estimation method for lead-acid batteries are presented. In the algorithm the measurements of battery’s terminal voltage, current and temperature are used in the process of SOC calculation. The thesis was written in cooperation with Micropower AB. The algorithm was designed to fulfill the specific requirements of the electric vehicles application: an error below 5% of SOC, computational simplicity and the possibility of being implemented in a basic programming languages. The current used method at Micropower, Coulomb counting, is compared with a method presented by Chiasson and Vairamohan 2005 based on modified Thevein circuit during charging and discharging of the battery. The Thevenin based method gave better result compared to Coulomb counting but seems not to fulfill Micropowers requirements. A correction method based on periods of no charging or discharging, possible to be used together with Coulomb counting as well as with the Thevenin method was developed. The evaluation method indicates that when using also the correction method the Micropowers requirements are fulfilled. / I detta papper, är ett laddningstillstånd (SOC) och hälsotillstånd (SOH) skattningsmetod för blybatterier presenteras. I algoritmen mätningarna av batteriets polspänning, ström och temperatur används i processen för SOC beräkning. Avhandlingen är skriven i samarbete med Micropower AB. Algoritmen har utformats för att uppfylla de särskilda kraven för elektriska fordon: ett fel under 5% av SOC, computational enkelhet och möjligheten att genomföras i ett grundläggande programmeringsspråk. Den nuvarande metoden vid Micropower, Coulomb räkning, jämförs med en metod som presenteras av Chiasson och Vairamohan 2005 baserad på modifierad Thevein kretsen under laddning och urladdning av batteriet.

The lead-acid batteries are the most commonly used electrochemical power sources and are the oldest type of secondary battery cells. This master thesis provides a short introduction to the lead-acid batteries. It shows possible ways of sorting from different points of view, describes construction of lead-acid batteries, parameters of lead-acid batteries and electrochemical and physical reactions inside the battery. Futher the thesis deals with pulse charging of lead-acid batteries. The thesis describes the production of a set of experimental electrodes for electrochemical workplace resources. The thesis introduces the develepment environment Agilent VEE PRO and demonstrates its capabilities. The final part of this thesis are experiments focusing on the pulse charging using negative current pulses and evaluate the effect of different pulse modes on cells.

This project deals with the design and realisation of a set that will work as a power supply point with electricity generated from renewable energy sources. The theoretical part deals with information about renewable energy sources and energy storage options. In the practical part, a mobile kit for powering variable message traffic signs is designed. It uses photovoltaic panels and stores energy in a lead-acid battery. A methanol fuel cell is used for backup power. The device is adapted for use in road traffic and meets the requirements of the relevant authorities. To verify the stability of the structure, there were performed static calculations, which proved the ability of the device to withstand wind stress. Part of the work was to draw a complete production documentation, which was used to create a test sample. Long-term measurements of energy flows in the system were performed on that sample. These measurements confirmed the ability of the device to operate autonomously and the possibility of using it for the required purpose.

The thesis is focused on remitting lead-acid segments of partial charge mode which simulates the conditions in HEV. The experimental cells were submitted to different pressures on the electrode system. The main aim of the thesis was to minimize the irreversible sulphating of the negative electrodes, which are in the PSoC regime limiting in the overall life of lead-acid accumulators. All cells were submitted to measurement of the negative electrode potentials, resistance of active materials, contact resistance of the grid – the active material and measurements of pressure changes during three PSoC cycles.

The lead-acid batteries are the most commonly used electrochemical power sources and are the oldest type of secondary battery cells. This master thesis provides a short introduction to the lead-acid batteries and shows possible ways of sorting from different points of view. Thesis describes construction of lead-acid batteries, parameters of lead-acid batteries, electrochemical and physical reactions inside the battery. Futher the thesis deals with pulse charging of lead-acid batteries. In the next part of the thesis is described the production of a set of experimental electrodes for electrochemical workplace resources. The final part of this thesis are experiments focusing on the pulse charging using negative current pulses and evaluate the effect of different pulse modes on cells.

The aim of this master´s thesis is optimalization and methods of measuring the internal resistance of lead acid accumulator. First focus is on the analysis of properties of lead acid accumulators, their construction and negative effects. After that a method of measuring the internal resistance of experimental accumulator is processed. In this thesis practical design of measuring workplace is completed. The frequency analysis of impedance of charging and discharging accumulator is performed. After that the graph of internal resistance for various amplitude intensities, for various signal forms and also for various size of frequencies of alternating current are processed. The result of this thesis is a comparison of graphic works addictions charging and discharging characteristics of lead acid accumulator and determination of optimal amplitude, form and intensity of frequency of alternating current in point when internal resistance is evaluated correctly.

This diploma thesis is focused on design of lead acid baterry charger. First chapters describes the charging and discharging principes. This paper also shows basics types of lead acid batteries, their distribution depends on maintenance and part connected to the processes connected to the charging and discharging of the acumulators. Following part is focused on theoretical design of the charger with set up of parameters. Diploma thesis also contains comparsion of requested and real parameters of the charger.