Subsequent to the studies on precursor lead-acid systems by Daniel, Grove and Sindesten, practical lead-acid batteries began with the research and inventions of Raymond Gaston Planté in France as early as in 1859, and, even to-day, lead-acid battery remains the most successful battery system ever developed, and no other battery is yet able to compete with lead-acid batteries on cost grounds, albeit batteries based on other chemistries are rapidly catching up. In the past, although lead-acid battery designs have been optimized in several different directions, there are still certain new challenges facing the lead-acid battery designers as additional failure modes become evident in various use modes. There are three types of lead-acid batteries in common use: (a) batteries with flooded or excess electrolyte, (b) low-maintenance lead-acid batteries with a large excess of electrolyte, and (c) batteries with immobilized electrolyte and a pressure-sensitive valve usually referred to as absorptive glass-microfibre (AGM) valve-regulated lead-acid (VRLA) batteries. The flooded-electrolyte lead-acid battery requires checking of specific gravity of electrolyte, periodic addition of water to maintain electrolyte level above the plates and recharge soon after discharge to prevent hard sulfation that causes loss of capacity. The emission of acid fumes corrodes metallic parts in the vicinity of the battery, and the seepage of acid on the top cover of the batteries leads to leakage current resulting in increased self-discharge and ground-shunt hazards. To overcome these problems, AGMVRLA batteries based on oxygen-recombination cycle have emerged. These batteries offer the freedom of battery placement, cyclability without the addition of water or checking the specific gravity, increased safety, and superior performance in some instances. Both flooded-electrolyte and AGM-VRLA batteries can suffer from acid stratification. But, AGM-VRLA batteries are especially susceptible to failures owing to the heat generated by oxygen recombination within the cells as well as due to cell-to-cell variations in electrolyte volumes. Indeed, partial heating of AGM-VRLA batteries could cause dry-out with grid corrosion and even lead to thermal runaway. Consequently, mitigating temperature variations in AGM-VRLA batteries becomes seminal to their commercial success. A dissipation of local heat within the AGM-VRLA batteries can be achieved by adequately filling the void volume in the battery with a thermally conducting gel, such as a gel formed from colloidal silica and sulfuric-acid electrolyte. Although, conventional lead-acid batteries are considered rather a matured technology, significant research and development efforts are currently under way to enhance their performance. Indeed, many improvements have been made in the lead-acid battery since its invention, and although the essential electrochemistry remains unchanged, the modern lead-acid batteries have little semblance to those produced 50 years ago. Over the years, seminal advances have been made in the lead-alloys used, in the materials and design of separators, in battery packaging and in their construction methods, which have led to lead-acid batteries with improved performance, lighter weight and lower cost. This thesis is an attempt to develop lightweight hybrid-VRLA batteries.

Orientador: William Dias Belangero / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-28T23:43:39Z (GMT). No. of bitstreams: 1 Faria_LidiaDornelasde_M.pdf: 3066212 bytes, checksum: 6cb5506682740e2fcb2de4b1694998a3 (MD5) Previous issue date: 2015 / Resumo: A Terapia por ondas de choque (TOC) é uma alternativa não invasiva utilizada como método de indução a formação óssea que consiste em pulsos sonoros de alta energia transmitidas de modo focal a um tecido específico. Artigos demonstram aumento de vascularização, que ativação de proteínas como BMP (bone morphogenic protein) e Erk (extracellular signal-regulated kinase) induzindo diferenciação osteogênica após sua utilização no tecido ósseo. O presente estudo visou avaliar os níveis das proteínas Erk e Akt (akutely transforming), envolvidas na cascata protéica responsiva a deformação celular gerada por estímulo mecânico e consequente transformação em estímulo bioquímico induzindo a osteogênese. Os animais selecionados para o estudo foram anestesiados e divididos em dois diferentes grupos, onde no dia 1, o primeiro grupo foi submetido a TOC em sessão única de 500 impulsos gerados por aparelho eletrohidráulico a 0,12mJ/mm²na tíbia intacta e o segundo não recebeu TOC. Na sequência, os animais foram divididos em 3 subgrupos para cada tempo de segmento de 7, 14 e 21 dias A determinação dos níveis das proteínas propostas foi realizada por meio de immunoblotting. A fosforilação das proteínas Erk e Akt dos tecidos ósseos das tíbias extraídas dos ratos aumentou nos grupos submetidos a TOC após 7, 14 e se manteve elevado até o 21° dia quando comparado ao controle / Abstract: Extracorporeal shock wave therapy (ESWT) is a non-invasive alternative used as a method for inducing bone formation that consists of high-energy acoustic pulses transmitted in a focal way to a specific tissue. Studies show increase in vascularization which activate proteins such as BMP and Erk inducing osteogenic differentiation after its use in the bone tissue. The present study aimed at evaluating the levels of Erk and AKT proteins involved in the protein cascade responsive to cell deformation in biochemical stimulus inducing osteogenesis. The animals selected for the study were under anesthesia and divided in two different groups where on day 1 the first group was submitted to ESWT in one 500 pulse-session generated by an electrohydraulic device at 0,12mJ/mm² in intact tibia and fibula and the second did not receive ESWT. Then the animals were divided into 3 sub-groups, one for each segment times of 7, 14 and 21 days. Immunoblotting analysis was performed to determine the levels of the proposed proteins. The Erk and Akt protein phosphorylation of the bone tissues of extracted tibia from the animals increased in the groups submitted to ESWT and kept elevated until the 21st day when compared to the control group / Mestrado / Fisiopatologia Cirúrgica / Mestra em Ciências

The task of research work is to study new mechanisms and to minimize disturbance of lead batteries for hybrid electric vehicles. Those arising under the PSoC (Partial State of Charge) and is linked to irreversible sulphation mainly negative electrodes. As one solution to prevent sulphation of the negative electrode appears to be the active ingredients in a negative matter. In the investigated electrodes is verified the influence of carbon, titanium dioxide and silica on the grain size of the order of nanometers.

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.

Lead-acid batteries of hybrid electric vehicles (HEV) are functioning in PSoC regime (Partial State of Charge). In PSoC regime new fail mechanisms occur. These mechanisms usually lead to nonreversible sulphation of negative electrodes. Main aim of this research is to avoid negative electrode sulphation and to improve lifetime of lead-acid accumulators used in HEV.

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.

This thesis deals with issues of the issue lead-acid batteries and their application in mode of hybrid electric vehicle. The experiment is focused on the production of electrodes to determine the effect five types of additives in negative active mass in PsoC(Partial State of Charge) mode. This simulates conditions occurring in the mode of hybrid electric vehicles (HEV).

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.

This diploma thesis deals with the design of a partially integrated charge pump in 0.25 micron technology ACMOS. The work is divided into two main parts, theoretical and practical. The theoretical section describes in detail various topologies of higher voltage generation of a charge pump and selected methods of regulating the output voltage of charge pumps. The practical part deals with the the actual design of a charge pump together with the arguments for the choice of the TPVD topology and the type of the regulation. Three regulation methods of a charge pump were implemented, tested and are dealt with: Pulse Skip, Constant frequency and PWM. There are 3 sub chapters, each describing a different regulation method, defining all the key elements of the design of such a charge pump and the results of the simulations are discussed. Conclusion of the thesis summarizes the results of the design of charge pumps, comparing them on the basis of the chosen type of output voltage regulation.

Diploma thesis work includes simulation of compensation of control for discrete. The aim of the work is a solution positioning control of servomotor drive piston, which is controlled by pass of the pressure oil with the help of several electromagnetically controlled switchboards with the orifice in the output channels. The verification activities of the regulated system is done using simulation in Matlab/Simulink and Matlab/Simulink, Matlab/Hydrosim. The requirement on the created model is to verify the behavior of the system to be modified to be used for the further development of the issue