• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 29
  • 15
  • 9
  • 4
  • 3
  • 1
  • 1
  • Tagged with
  • 66
  • 66
  • 66
  • 27
  • 26
  • 16
  • 15
  • 13
  • 11
  • 11
  • 10
  • 9
  • 9
  • 9
  • 8
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Characterisation of Used Lead-Acid Batteries for Feed Optimisation in Secondary Lead Production / Karakterisering av uttjänta blybatterier för optimering av ingående material i sekundär blyproduktion

Neiström, Linda January 2018 (has links)
Used lead-acid batteries are the main raw material in secondary lead production. Technologicalprogress in the car industry, have raised concerns regarding the lead-acid battery’s leading positionas electrochemical storage system in the future. However, the lead-acid battery industry isadvancing with innovations, such as hybrid and micro-hybrid vehicles, and is believed to have acontinued important role in the rechargeable battery market. Lead is one of the most investigatedmetal due to concerns from society regarding the negative effect on human health and theenvironment. Consequently, that has led to tighter controls and regulations of the lead processingindustry which, in turn, has led to technological improvement concerning design and operation ofthe lead processing plants. Used lead-acid batteries have a complex composition with a variety ofcomponents made of lead (i.e., metallic, oxide or sulphate) and non-lead materials (plastics andelectrolyte). Traditionally, battery recycling is done without separating those components.However, to optimise the use of resources and decrease the environmental impact of secondarylead production, a pre-treatment step to the batteries recycling is desired. The pre-treatment iscomprised of breaking the batteries and separation of the battery components. The aim of the present thesis, was to study the components of a used lead-acid battery, which willbe the outgoing material of a future plastic separation plant at Boliden Bergsöe, and their effect onthe process. Furthermore, the study aimed at investigating the possibilities to adjust the feedcomposition for further process optimisation and improvement of the process quality in terms ofenergy usages and environmental impact. This was done by characterise, through qualitative andquantitative composition and mass distribution, the fractions in a used lead-acid car battery. Four lead-acid car batteries were provided for dismantling to study mass distribution, and toliberate the components for further analysis. The analytical techniques used in this study werequalitative and quantitative (Rietveld) XRD analysis, SEM-EDS and TGA. The result showed thatoverestimated amount of battery separators (PE) has been used at production planning in energyandemission calculations, which can cause financial losses due to overpaid emission tax. The pastefraction showed a large variation in mass between the studied batteries and consists mostly ofPbSO4. Large variation in the paste mass may cause uneven sulphur emission from smelter.Consequently, this reinforces the need for implementation of the separation of the battery feed fora better control of the paste addition to the smelter. When PE decomposes in the shaft furnace the remaining ash will mainly consist of silica, whichwill affect the sulphur uptake in the shaft furnace. The large content of silica leads to a lower energycontribution to the process; however, a lower content of hydrocarbons leads to lower CO2emissions. If a desulphurisation of the pastes would be implemented, it is believed to affect theprocess through a decreased need of coke and iron. A reduced usage of coke and iron would lowerthe production costs and lead to decreased CO2 emissions. A desulphurisation will also decreasethe lead sulphate content in the feed, thus lead to better control of the sulphur emissions. This study provides additional support and further insight into composition and mass distributionof the components in a lead-acid battery. Furthermore, the study indicates possible impact of thefuture separation on the new feed properties and on the subsequent processing.
42

Studies On Lead-Acid, Nickel-Based And Silver-Zinc Rechargeable Batteries

Hariprakash, B 05 1900 (has links) (PDF)
No description available.
43

Kombinovaný vliv skelných vláken a oxidu titaničitého jako aditiv záporné elektrody na vlastnosti olověného akumulátoru. / The combined effect of glass fibers and titanium oxide as the negative electrode additive on the properties of the lead accumulator

Gerlich, Jakub January 2017 (has links)
This thesis deals with the problematic of lead acid batteries for HEVs. It starts with classification of electrochemical cells then proceeds to focus on lead acid batteries, mainly because they are the most used source of electrical power in automotive industry. The practical part of the work describes the process of manufacturing the electrode system used in the later parts. The experimental part is focused on the behaviour of the cells under conditions that appear in hybrid electric vehicles. The effect of aditives in active matter of the negative electrode on the parameters of the cells is observed, such as voltage, capacity and operating life
44

Sledování vlivu teploty na vlastnosti olověných akumulátorů / Monitoring of temperature influence on properties of lead-acid accumulators

Musil, Petr January 2019 (has links)
This thesis deals with lead-acid battery, its parameters and temperature behaviour of this electro-chemical source of power. In the theory section, types of batteries are presented, followed by their primary parameters and electro-chemical reactions, which take part in battery cells. This section also contains information about charging stages, detailed description of each battery part, used materials, construction of the battery and degradation processes caused by battery operation. The practictal section of this thesis offers a measurement scheme for automated measuring workstation. Furthermore, the practical section presents results of measurements on parameters of chosen lead-acid battery types, it also contains long-term deep battery cycling and measurements under elevated temperatures. Detailed comparison of measurements results and datasheet values is included. Conclusion sums up parameters of chosen lead-acid battery types and their feasibility for further usage in power backuping.
45

Automatizované měřicí pracoviště pokusných článků olověného akumulátoru / Automatized measuring apparatus for lead acid battery cells

Čapek, Ivo January 2008 (has links)
This presented work deals with the development of an automated station for the measuring of experimental cells of the Lead Acid Battery. The principle is to design a measuring station and make programs for cycling of cells in standard and PSoC modes.
46

Vliv přítlaku a aditiv na životnost olověného akumulátoru pro hybridní elektrická vozidla / Influence of pressure and additives on cycle life of lead acid battery for hybrid electric vehicle

Přívozník, Tomáš January 2012 (has links)
This master’s thesis deals with lead acid battery in hybrid electric vehicles which operating at mode of partial state of charge (PSoC). In this mode, there is often a negative electrode degradation mostly due to irreversible mechanism of suphation. The idea of this work is detect ideal value of mechanical pressure exerted on active mass of negative electrode in combination with additives to prevent mechanism of sulphation and lead to increased cycle life of lead acid battery.
47

Studium vnitřního odporu článku olověného akumulátoru pro hybridní elektrická vozidla / Study of internal resistance of the lead acid battery cell for hybrid electric vehicles

Vojtíšek, Miloš January 2013 (has links)
This work aims on acumulators for hybrid vehicles and deals particularly with research of inner-resistance of the lead-acid batteries. There is a brief characterization of hybrid cars in first part of the tesis. Second part is dealing with design of experimental measurement setup for measurement of lead-acid electrochemical cells. Set of experiments on several cells was performed, description of experiments and results in graphical form are present.
48

Optimalizace užitných vlastností olověných akumulátorů / Optimization of use properties Lead-Acid batteries

Lábus, Radek January 2015 (has links)
This thesis focuses on the limitations of degradation mechanisms of Lead-Acid batteries, which significantly contributes unequal distribution of current (and therefore internal resistance, charge passed and power loss) on the surface of the electrodes of Lead-Acid battery. The unevenness of distribution of these parameters significantly influences the distribution of current tabs on the electrodes. In this work it was developed realistic model of Lead-Acid battery cell with plate electrodes with different variants of the distribution of current tabs. Measured results obtained in this model were compared with the results found out from the mathematical simulations. Through these simulations, it was possible to take a look deeply into the processes and changes in the electrodes of Lead-Acid batteries during discharge. Goal of this work was for predefined variants of positioning of the current tabs to simulate distribution of current, internal resistance, charge passed and power loss during discharge. Another goal was to compare the different variants and to find the optimal variant of current tabs positioning based on minimizing of unevenness of examined variables distribution.
49

Comparative life cycle assessment of different lithium-ion battery chemistries and lead-acid batteries for grid storage application

Yudhistira, Ryutaka January 2021 (has links)
With the rapid increase of renewable energy in the electricity grids, the need for energy storage continues to grow. One of the technologies that are gaining interest for utility-scale energy storage is lithium-ion battery energy storage systems. However, their environmental impact is inevitably put into question against lead-acid battery storage systems. Therefore, this study aims to conduct a comparative life cycle assessment (LCA) to contrast the environmental impact of utilizing lithium-ion batteries and lead-acid batteries for stationary applications, specifically grid storage. The main tools in this study include Microsoft Excel for the life cycle inventory and OpenLCA for life cycle modelling and sensitivity analysis. In this research, a cradle-to-grave LCA for three lithium-ion battery chemistries (i.e. lithium iron phosphate, nickel cobalt manganese, and nickel cobalt aluminium) is conducted. The impact categories are aligned with the Environmental Footprint impact assessment methodology described by the European Commission. The standby grid operation scenario is considered for estimating the environmental impacts, where the batteries would deliver 4,800 kWh of electric energy throughout 20 years. Consequently, the functional unit will be in per kWh energy delivered. The lead-acid battery system has the following environmental impact values (in per kWh energy delivered): 2 kg CO2-eq. for climate change, 33 MJ for fossil resource use, 0.02 mol H+-eq. for acidification, 10-7 disease incidence for particulate emission, and 8x10-4 kg Sb-eq. for minerals resource use. Going back to the lithium-ion batteries systems, for the climate change and fossil resource use impact categories, the best performer is found to be the nickel cobalt aluminium (NCA) lithium-ion battery, with 46% and 45% less impact than lead-acid for the respective categories. On the other hand, the nickel manganese cobalt (NMC) was the best for the acidification and particulate emission impact categories with respective 65% and 51% better performance compared to lead-acid batteries. Finally, for the minerals and metals resource use category, the lithium iron phosphate battery (LFP) is estimated to be the best performer, which is 94% less than lead-acid. To conclude, the life cycle stage determined to have the largest contribution for most of the impact categories was the use stage, which then becomes the subject to a sensitivity analysis. The sensitivity analysis was done by varying the renewable contribution of the electricity grids in the use phase. Overall, the lithium-ion batteries systems have less environmental impact than lead-acid batteries systems, for the observed impact categories. The findings of this thesis can be used as a reference to decide whether to replace lead-acid batteries with lithium-ion batteries for grid energy storage from an environmental impact perspective. / Med den snabba ökningen av förnybar energi i elnäten, fortsätter behovet av energilagring att växa. En av de tekniker som växer intresse för energilagring på nyttan är litiumjon batteriets energilagringssystem. Emellertid, deras miljöpåverkan ifrågasätts oundvikligen mot blysyrabatteri lagringssystem. Därför syftar denna studie till att göra en komparativ livscykelanalys (LCA) för att komparera miljöpåverkan av att använda litiumjonbatterier och blybatterier för stationära applikationer, särskilt för nätlagring. I denna forskning genomfördes en vagga-till-grav-LCA (eller cradle-to-grave i engelska) för tre litiumjonbatterikemi (litium järn fosfat, nickel kobolt mangan, och nickel cobalt aluminium). Effektkategorier anpassades till miljökonsekvensbedömning metoden som beskrivs av Europeiska kommissionen. Det användningsfall scenariot för batterierna var standby läget, där batterierna leverera 4800 kWh elektrisk energi för 20 år. Följaktligen den funktionella unit är i ‘per kWh levererad energi’. Blysyrabatteriet hade följande ungefärliga miljöpåverkansvärden (i per kWh levererad energi): 2 kg CO2-eq. för climate change, 33 MJ för fossil resource use, 0.02 mol H+-eq. för acidification, 10-7 disease incidence för particulate emission, and 8x10-4 kg Sb-eq. för minerals resource use. Tillbaka till litiumjonbatterierna, för climate change och fossil resource use resursanvändnings kategorier, den bäst presterande var litiumjonbatteriet nickel kobolt aluminium (NCA). Det hade 46% och 45% mindre påverkan än blysyrabatteriet för respektive kategori. Å andra sidan, var nickel mangan kobolt (NMC) bäst för acidifcation och particulate emission kategorier. De är 65% och 51% bättre än blysyra för kategorierna. Slutligen, litium järn fosfat batteriet (LFP) är det bäst presterande för resource use of minerals and metals kategoriet, vilket det är 94% mindre än blysyra. Avslutningsvis, det livscykelstadier som var bestämt att ha det största bidraget för de flesta av påverkningskategorierna är användningsstadiet, som sedan blir föremål för en känslighetsanalys. I slutändan, litiumjonbatterierna ha mindre miljöpåverkan än blybatterier i detta projekt, för de observerade slagkategorierna. Resultaten av denna avhandling kan sedan användas som referens för att avgöra om bly-syrabatterier ska ersättas med litiumjonbatterier för energilagring ur ett miljöeffektperspektiv.
50

Vliv vodivých keramik na životnost olověných akumulátorů / Influence of conductive ceramics on the life of lead acid batteries

Tobolák, Jakub January 2014 (has links)
This thesis is focused on lead-acid batteries used in hybrid electric vehicles. These cells work in specific conditions, particularly under partial charge referred to as PSOC. This fact is responsible for the premature loss of capacity cell lead-acid batteries and their short lifetime. The task of this thesis is to examine the effect of conductive ceramics as possible additives to the negative electrode active materials of lead-acid battery cells operating in a PSOC, in order to prolong their life.

Page generated in 0.064 seconds