This Master’s thesis deals with the lead-acid batteries, which are alternativ power supply. The lead-acid batteries are the oldest type of battery cells. This lead-acid batteries have a great use in hybrid electric vehicles (HEVs), which operate in different modes of vehicle operation. These modes correspond to the reactions taking place during discharging and charging the battery. The lead-acid batteries in hybrid electric vehicles work in mode PSoC. The practical part of the Master`s thesis examines how the characteristics of lead-acid batteries are modified due to admixture of glass fibers into negative active material and application of pressure to the electrode system.

The master thesis provides a brief introduction to the lead-acid batteries. The thesis describes an internal construction, electrochemical reactions inside the batery, the area of application and possible degradation effects. The next part deals with an analytic method of the measurement called electrochemical impedance spectroscopy. The thesis describes the principle of measurement, alternative equivalent circuits, the impedance of electrochemical cell and the analyse of recorded datas. In the practical part was assembled the functional lead-acid cell. After that, experimental measurement was passed on the lead-acid cell in discharge and in a different concentration of electrolyte. In the last part was created the simulation of treatment of an electrochemical cell in the development solution Agilent VEE and after that all the measurement results were compared with the simulation.

Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2017-07-12T21:44:11Z No. of bitstreams: 1 PGCA_Dissertacao_Fabio.pdf: 17456050 bytes, checksum: 0e14f30b37a0f91b865c29f80d2ff377 (MD5) / Made available in DSpace on 2017-07-12T21:44:11Z (GMT). No. of bitstreams: 1 PGCA_Dissertacao_Fabio.pdf: 17456050 bytes, checksum: 0e14f30b37a0f91b865c29f80d2ff377 (MD5) Previous issue date: 2016-08-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / There are presently market a wide range of batteries. These batteries come to meet the need of electric power supply for electronic devices unable to be connected to a source of electricity for a certain period of time. For this to happen, a battery goes through a cycle involving a charge period and a discharge period. Another point to be noted is that the vast majority of applications that utilize lead acid batteries have a supply voltage above 2 volts, the voltage which is provided by a single cell. For higher voltages, it is necessary to link various cells in series. According to manufacturers of lead acid batteries, if loading and unloading are carried out in accordance with the specifications provided for the product, ensures the maximum utilization of battery life, but failure to comply with these specifications can shorten the life of a battery lead acid in more than 50%. Given the above, this paper describes the design of a system to charge control, discharge control and load balancing for lead acid batteries for better efficiency and maximum utilization of the useful life of the batteries. / Atualmente, existe no mercado uma grande gama de baterias. Estes acumuladores v?m para suprir a necessidade de fornecimento de energia el?trica para dispositivos eletroeletr?nicos impossibilitados de serem conectados a uma fonte geradora de energia el?trica por um determinado per?odo de tempo. Para que isso aconte?a, uma bateria passa por um ciclo que envolve um per?odo de carga e um per?odo de descarga. Outro ponto a ser observado ? que a grande maioria das aplica??es que utilizam baterias de chumbo ?cido possuem tens?o de alimenta??o superiores a 2 volts, que ? a tens?o fornecida por uma ?nica c?lula. Para obter tens?es maiores, faz-se necess?ria a liga??o de v?rias c?lulas em s?rie. Segundo os fabricantes das baterias de chumbo ?cido, se forem realizadas cargas e descargas em conformidade com as especifica??es fornecidas para o produto, garante-se o aproveitamento m?ximo da vida ?til da bateria, mas a inobserv?ncia destas especifica??es pode diminuir a vida ?til de uma bateria de chumbo ?cido em mais de 50%. Diante do exposto, este trabalho descreve o projeto de um sistema para controle de carga, controle de descarga e balanceamento de carga para baterias de chumbo ?cido que garanta uma melhor efici?ncia e o m?ximo aproveitamento da vida ?til destas baterias.

Made available in DSpace on 2017-07-24T19:38:05Z (GMT). No. of bitstreams: 1 Micheli Barbosa de Andrade.pdf: 2002962 bytes, checksum: 51f76c0895430f8d105003d680198199 (MD5) Previous issue date: 2011-02-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In Brazil, the main source of lead metal is derived from recycled lead-acid batteries by the pyrometallurgical process. The process consists in separating the components of lead-acid battery and subsequent fusion of the metal in the furnace to reduce the rotational type. Recycling is an economical alternative, sustainable and environmentally friendly but, recycling industries are potentially polluting. During the process, there is generating a large amount of slag, which may contain metals that were present in raw material or that were added to the reactions necessary to promote the recycling process. This slag is classified as Class I waste, hazardous waste, according to Brazilian standard NBR 10004 Brazilian Association of Technical Standards and (ABNT) and must have as the final destination of hazardous waste landfill. The contribution of this paper lies in the chemical evaluation of the slag from the recycling of lead batteries; structural characterizations, indicate that in turn, forms of association of the metal, and their potential to mobilize heavy metals from the method of Tessier (Method of selective extraction applied to soils and sediments) applied to the residue in order to evaluate the conditions in which metals can be removed in the same. Data from x-ray fluorescence (XRF) showed a predominance of the elements Fe, Si, S, Al, Ca, Pb and Zn, with the initial sample had a higher quality metals and in a much higher sample. By x-ray diffraction was obtained to confirm these associated elements, forming compounds. The fayalite was present in all samples, mainly in lower and central samples, as well as lead sulfide and iron sulfide, the large overlap of the peaks difficult to visualize the phases. The evaluation of the mobilization of metals from the Tessier method and comparison with the VMP CONAMA 357 demonstrated the potential risks, direct or indirect, of the mobilization of these metals. With the application of different conditions of leaching of the method of Tessier, one can observe that treatment of these slags in pH 5.0 extracts about 90% of lead present in the slag. / No Brasil, a principal fonte de chumbo metalico e obtido a partir da reciclagem de baterias de chumbo-acido pelo processo pirometalurgico. O processo consiste na separacao dos componentes da bateria de chumbo-acido e posterior fusao dos metais no forno de reducao do tipo rotatorio. Esta e uma alternativa economica, sustentavel e ecologicamente correta mas, as industrias de reciclagem sao potencialmente poluidoras. Durante o processo, ha geracao de uma grande quantidade de escoria, que pode conter metais que estavam presentes na matéria prima ou que foram adicionados para promover as reacoes necessarias ao processo. Essa escoria e classificada como residuo de classe I, residuo perigoso, segundo a norma brasileira NBR 10004 da Associacao Brasileira de Normas e Tecnicas (ABNT) e deve ter como destino final o aterro de industriais. A contribuicao deste estudo reside na avaliacao quimica da escoria proveniente da reciclagem de baterias de chumbo; as caracterizacoes estruturais, que indicam por sua vez, as formas de associacao do metal; e o seu o potencial de mobilizacao de metais a partir do metodo de Tessier (metodo de extracoes seletivas aplicado a solos e sedimentos) aplicado ao residuo como forma de avaliar as condicoes em que os metais podem ser removidos do mesmo. Pelos dados de fluorescencia de raios x (FRX) observou-se predominância dos elementos Fe, Si, S, Al, Ca, Pb e Zn, sendo que na amostra inicial houve uma maior qualidade de metais e na amostra superior uma maior quantidade. Pela difracao de raios x obteve-se a confirmacao destes elementos associados, formando compostos. A fayalita estava presente em todas as amostras, principalmente nas amostras inferior e central, assim como sulfeto de chumbo e sulfeto de ferro; a grande superposicao dos picos dificultou a visualizacao das fases. A avaliacao da mobilizacao dos metais a partir do metodo de Tessier e a comparacao com os VMP do CONAMA 357 demonstraram os riscos potenciais, diretos ou indiretos, da mobilizacao desses metais. Com a aplicacao das diferentes condicoes de lixiviação do metodo de Tessier, pode-se observar que o tratamento dessas escorias em pH 5,0 extrai cerca de 90% do chumbo presente na escoria.

Unmanned ground and aerial vehicles (UGVs and UAVs) have strict payload limitations, limited free space affecting on board power availability resulting in limited endurance and operational range. This limitation is exacerbated by the addition of sensors, actuators and other related equipment needed to accomplish mission objectives in diverse applications. Two energy sources are mainly available for mobile applications; batteries and fuel cells. Batteries are a relatively cheap, tested technology with good performance under varying loads. On the other hand, fuel cells offer fast and easy refueling solutions. Furthermore, preliminary studies have shown that a hybrid system can combine the advantages of both technologies offering a superior system. It is true that for most outdoors applications, payload needs, sensor suite utilization and energy requirements are apriori unpredictable. This makes proper sizing of energy storage devices and the prediction of remaining available energy rather difficult tasks. This research proposes an indirect way of improving the operational range for UAVs of Vertical Take Off and Landing (VTOLs), since the VTOL vehicle is transported to the mission site without the need to fly. The proposed gimballed platform, which will be a power source itself, rotates around two axes perpendicular to each other, allowing the VTOL to take-off and land, regardless of the position of the UGV, while securing it during transportation. The UGV can also serve as a charging station for the VTOL. Furthermore, this research proposes a Matlab Simulation tool that can simulate the energy and power demand of small to mid-sized robotic vehicles. This model will simulate the power consumption in the motors based on Skid steering, road gradient, linear and angular velocity. With the energy and power requirements estimated, a Matlab optimization tool is proposed to be used to determine the optimal configuration of a power system for mobile applications under constraints relating to capacity/runtime, weight, volume, cost, and system complexity. The configuration will be based on commercially available batteries, and fuel cells to significantly reduce cost and delivery time. The optimization tool can be used for any mobile application. Finally, a new model is proposed for the accurate prediction of battery runtime and remaining energy for single battery discharge. This model reformulates Peukert's equation and achieves higher accuracy by introducing a new concept of variable exponent which is a function of battery capacity and discharge current.

This thesis studies State-of-Charge (SOC) method for widely used lead-acid batteries and the most prospective lithium-ion batteries. First, the relationship between the battery capacity and the open-circuit-voltage under different charging/discharging currents is investigated based on the equivalent circuit. Experimental results indicate that the open-circuit-voltage of the lead-acid battery varies regularly with the charging/discharging current and the duration of time for the battery disconnected from the load. Accordingly, a dynamic open-circuit-voltage method in considerations the open-circuit-time and the previous operating current is capable of precisely estimating the battery capacity in a shorter time. As for the lithium-ion batteries, their charging/discharging characteristics reveal that the Coulomb/Ampere-Hour Counting method is capable of yielding accurate estimations. Finally, through the experiments that emulate practical operations, the SOC estimations of batteries are verified to demonstrate the effectiveness and accuracy of the proposed methods.

Thesis (MEng)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: This thesis presents the design of a DSP based controller system for an auxiliary converter for generic energy storage connection to a line-interactive power compensator. The aim is to utilize a wide range of energy storage systems and incorporate them into the existing power compensator. This was done by adding a second converter to the system. The new controller was developed to control this converter and thereby the energy storage. A study was done on lead acid batteries, flow batteries and flywheels in order to gain a basic understanding of these systems and identify the requirements for their control. Based on these findings, a new DSP based controller and measuring system was developed. To test the new system a dc to dc converter was implemented for the control of lead acid and flow batteries. A dc to ac converter was also tested for the control of flywheel energy storage. / AFRIKAANSE OPSOMMING: Die tesis handeloor die ontwerp van'n DSP gebaseerde beheerstelsel vir 'n Iyninteraktiewe on-onderbreekbare kragbron met drywings-kompensasie met 'n hulp omsetter vir algemene enegiestoor koppeling. The doel is om 'n wye verskeindheid energie store in die huidige drywings elektroniese stelsel te inkorporeer. 'n Tweede omstetter is by die stelsel gevoeg om die energie stelsel te beheer. 'n Nuwe beheerder is ontwikkel om die omsetter te beheer en daardeur die energie stoor. Loodsuur batterye, vloei batterye en vliegwiele is ondersoek om 'n basiese begrip te vorm en te identifiseer wat nodig is vir die beheer van sulke energie store. Die nuwe DSP beheerder en meetstelsel is ontwikkel gebaseer op hierde ondervindings. Om die nuwe beheerstelsel te toets is 'n gs na gs omsetter geïmplementeer vir die beheer van loodsuur en floei batterye. Die omsetter is geherkonfigureer na 'n gs na ws opstelling en getoets. Die konfigurasie word gebruik vir die beheer van vliegwiele.

At the nuclear power plant in Forsmark, several different securitysystems are used. One of these systems comprises uninterruptiblepower supply (UPS) and consists of lead-acid batteries. The batteries are dimensioned to supply the load for two hours and are constantly charged. This to ensure they’re fully charged in case the regular power source fails. Discoveries have been made that the lifetime of the batteries are shorter than calculated and this thesis examines if the environmental temperature is the reason. Higher temperatures will cause the batteries to corrode more easily which leads to a decrease of the capacity of the batteries. The temperature have been logged in selected areas during two weeks in April 2018. The results have been compared to the meteorological temperature and analyzed together with capacity tests of the batteries. The batteries that have inferior results in the capacity tests are placed in spaces with high temperatures and needs to be cooled as soon as possible. In longterm, installation of a proper cooling system is recommended. To measure the temperature during several periods throughout the year ensures if the meteorological temperature affects the environment of the batteries. If so, more spaces where batteries are placed may need cooling during the hotter period of the year.

This Master thesis deals with modification of lead battery charger connection. In particular, changes are made to the control board. The theoretical part describes the principle of charging lead batteries and the description of the basic types of switching power supplies. Furthermore, the dimensioning of important components in the circuit together with the optimization of the switching frequency and the parameters of the high-frequency transformer are also presented. At the end of the thesis is the procedure of assembling the whole charger.

The lead-acid bateries for hybrid-electric vehicle (HEV) working under high-rate partial-state-of-charge (HRPSoC) conditions. The negative plates of lead-acid batteries have low charge acceptance. The cycle life of the batteries is dependent on the rate accumulation of PbSO4 on the negative plates. Addition of some carbon or graphite forms to the negative paste mix improves the charge efficieny and slows down sulfation of the negative plates. The master’s thesis wants to explain the contribution of electrochemically active carbon (EAC) additives to the mechanis of the electrochemical reaction of charge of the negative plates.