Made available in DSpace on 2018-08-01T21:58:48Z (GMT). No. of bitstreams: 1 tese_10827_Dissertação Jenifer Rigo Almeida - FINAL.pdf: 2105933 bytes, checksum: 17fccc5751be81765e75282388ce4b0c (MD5) Previous issue date: 2017-03-27 / Baterias de íon-Lítio (LIBs) exauridas são consideradas resíduos sólidos perigosos devido à presença de metais e compostos orgânicos em sua composição, representando desperdício de recursos naturais não renováveis e de metais valiosos quando descartadas. Este trabalho tem por objetivo fornecer dados quantitativos sobre a composição química do material ativo do cátodo (MAC) de diferentes LIBs exauridas visando monitorar variações com o passar dos anos e auxiliar nos processos de reciclagem do material. Os elementos Al, Co, Cr, Cu, Ga, Li, Mg, Mn, Ni, Ti e Zn foram determinados por espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES) após lixiviação ácida empregando 2,0 mol.L-1 de ácido cítrico (HCit) e H2O2 (0,25 mol.L-1) como alternativa ambientalmente favorável. As condições otimizadas para adequação do meio às curvas analíticas foram: para Al, Cu: Curva de HCit diluído 10 vezes sem padrão interno (PI); para Co, Li, Mn, Ni: Curva de HCit diluído 500 vezes sem PI; para Ga, Zn: Curva de HCit diluído 10 vezes com Y. O procedimento analítico empregado alcançou limites de detecção de 0,01 mg.L-1 para Al; 0,20 mg.L-1 para Co; 0,006 mg.L-1 para Cr; 0,02 mg.L-1 para Cu; 0,004 mg.L-1 para Ga; 0,02 mg.L-1 para Li; 0,0005 mg.L-1 para Mg; 0,07 mg.L-1 para Mn; 0,70 mg.L-1 para Ni; 0,0005 mg.L-1 para Ti e 0,007 mg.L-1 para Zn. A exatidão do procedimento foi confirmada por testes de adição e recuperação dos analitos obtendo-se valores entre 92-113 %. Os elementos majoritários Co (43-67 % m/m), Li (5,3-6,8 % m/m), Mn (0,8-8,2 % m/m), Ni (0,1-11,7 % m/m) e Al (0,06-3,2 % m/m) e os elementos minoritários Cr (0,0005-0,002 % m/m), Cu (0,01-0,05 % m/m), Mg (0,005-0,02 % m/m), Ti (0,001-0,07 % m/m), Ga (0,0009-0,03 % m/m) e Zn (0,009-0,05 % m/m) demonstraram que a composição do MAC pode variar de acordo com a capacidade e ano de fabricação. As baterias mais antigas foram as que apresentaram maiores teores de Co e Li. As baterias de menor capacidade foram as que continham os maiores teores de Mn e Ni, indicando que o Co foi substituído. O pó do MAC e o resíduo após lixiviação foram caracterizados por difratometria de raios X (DRX) obtendo-se LiCoO2 como composto principal, podendo ser reutilizado.

京都大学 / 0048 / 新制・課程博士 / 博士(人間・環境学) / 甲第21876号 / 人博第905号 / 新制||人||216(附属図書館) / 2018||人博||905(吉田南総合図書館) / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 内本 喜晴, 教授 田部 勢津久, 教授 吉田 鉄平 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(人間・環境学) / 甲第22548号 / 人博第951号 / 新制||人||226(附属図書館) / 2019||人博||951(吉田南総合図書館) / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 内本 喜晴, 教授 田部 勢津久, 准教授 藤原 直樹 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DFAM

The demand for Lithium-ion batteries (LIBs) has been growing exponentially in recent years due to the proliferation of electric vehicles (EV). A large amount of lithium-ion batteries are expected to reach their end-of-life (EOL) within five to seven years. The improper disposal of EOL lithium-ion batteries generates enormous amounts of flammable and explosive hazardous waste. Therefore, cost-effectively recycling LIBs becomes urgent needs. Lithium nickel cobalt manganese oxides (NCM) are one of the most essential cathode materials for EV applications due to their long cycle life, high capacity, and low cost. In 2008, 18.9% of Lithium-ion batteries used NCM cathode material worldwide while this number increased to 31% six years later. An environment–friendly and low-cost direct recycling process for NCM has been developed in this project. The goal of this project is to recycle the EOL NCM and yield battery-grade NCM with equivalent electrochemical performance compared to virgin materials. In order to achieve this goal, four different heat treatment conditions are investigated during the direct recycling process. From the experimental results, the charge and discharge capacities of the recycled material are stable (between 151-155 mAh/g) which is similar to that of the commercial MTI NCM when sintered at 850 °C for 12 hours in the air. In addition, the cycling performance of recycled NCM is better than the commercial MTI NCM up to 100 cycles. / Master of Science / The demand for Lithium-ion batteries has been growing exponentially in recent years due to the proliferation of electric vehicles. A large amount of lithium-ion batteries are expected to reach their end-of-life within five to seven years. The improper disposal of end-of-life lithium-ion batteries generates enormous amounts of flammable and explosive hazardous waste. Therefore, cost-effectively recycling Lithium-ion batteries becomes urgent needs. Lithium nickel cobalt manganese oxides are one of the most essential cathode materials for electric vehicles applications due to their long cycle life, high capacity, and low cost. In 2008, 18.9% of Lithium-ion batteries used Lithium nickel cobalt manganese oxides cathode material worldwide while this number increased to 31% six years later. An environment–friendly and low-cost direct recycling process for Lithium nickel cobalt manganese oxides material has been developed in this project. The goal of this project is to recycle the end-of-life manganese oxides cathode material. In order to achieve this goal, four different heat treatment conditions are investigated during the direct recycling process. From the experimental results, the cycling performance of recycled NCM is better than the commercial MTI NCM.

Conventional primary Li/CFx batteries employ graphite and polyvinylidene fluoride additives in the cathodes. These additives usher in some un-desired side-effects, such as lower battery capacities (mAh/g) and smaller current densities (mA/g). An innovative pretreatment was developed in this research in which CFx was subject to a “solvated electron” reduction to obtain a thin layer graphitic carbon coating on the CFx particle surfaces. Resistivity tests revealed that these partially reduced CFx particles have a higher conductivity at comparable graphitic carbon contents. Electrochemical discharge reactions demonstrated that batteries made from the reduced CFx were superior to the conventional batteries with higher current densities and higher capacities achieved. Impedance spectroscopy (EIS) studies found out that the reduced CFx particles have smaller cell reaction resistances, smaller double layer/intercalation capacitances and smaller mass transport resistances. It appears that use of reduced CFx has the potential to replace the conventional CFx plus additives as a cathode material in Li/CFx batteries.

No description available.

<p>Lithium-ion batteries provide a more cost-effective and non-toxic source of reusable energy compare to other energy sources. Several research studies have lead to production of some more promising cathode components for lithium ion batteries. Recently, a new series of pyrophosphate-based composition Li₂FeP₂O₇ and Li₂MnP₂O₇ has been reported as cathode materials. They have shown a 3D framework structure and the two Lithium-ions in the three-dimensional tunnel structure make it possible that more than one lithium ion be extracted during cycling. Lithium solid state nuclear magnetic resonance (NMR) is an effective technique to study this cathode material, not only for analyzing local structure, but also for investigation of the microscopic processes that take place in the battery.</p> <p>In this work, Li₂FeP₂O₇ and Li₂MnP₂O₇ have been synthesized. The lithium environment of these materials is studied using 1D ^6,7Li NMR. Assignment of Li₂MnP₂O₇ spectrum has been made based on Fermi-contact interaction and crystal structure. Both variable temperature experiment and 1D selective inversion NMR are used to establish Li-ion pathways as well as Li hopping rates for Li₂MnP₂O₇. Also, ⁷Li MAS NMR measurements are used to characterize Li environments in LixFeP₂O₇after being electrochemically cycled to different points, and preliminary results regard to changes to ion mobility in LixFeP₂O₇at different electrochemical cycled points are presents here, solid-solution (de)lithetiation process is confirmed for this material.</p> / Master of Science (MSc)

This thesis in its first part deals especially with characteristic of lithium ion accumulators in terms of their structure, electrochemical properties and also features of the most commonly used cathode materials. Especial attention is given to the high-voltage cathode material LiNi0,5Mn1,5O4 which cell voltage is close to 5V. The second practical part deals with the preparation of cathode materials based on LiNi0,5Mn1,5O4 with different temperatures in the second stage of annealing and analyzing them in terms of structure and electrochemical properties using appropriate measuring methods.

Die wachsende Weltbevölkerung und die stetigen Entwicklungen in der Industrie benötigen einerseits immer größere Mengen an Grundchemikalien und führen andererseits zu einem ständig steigenden Energiebedarf. Die Dissertation behandelt daher die Themen Zeolithe und Kathodenmaterialien, welche zwei aktuelle Forschungsschwerpunkte der chemischen Industrie darstellen. Der Fokus der Arbeit lag in der Steuerung der Partikelgröße durch die hydrothermale und mikrowellenunterstützte Kristallisation.

Indiana University-Purdue University Indianapolis (IUPUI) / In the last years, lithium-ion batteries (LIBs) have become the most important energy storage system for consumer electronics, electric vehicles, and smart grids. The development of lithium-ion batteries (LIBs) based on current practice allows an energy density increase estimated at 10% per year. However, the required power for portable electronic devices is predicted to increase at a much faster rate, namely 20% per year. Similarly, the global electric vehicle battery capacity is expected to increase from around 170 GWh per year today to 1.5 TWh per year in 2030--this is an increase of 125% per year. Without a breakthrough in battery design technology, it will be difficult to keep up with the increasing energy demand. To that end, a design methodology to accelerate the LIB development is needed. This can be achieved through the integration of electro-chemical numerical simulations and machine learning algorithms. To help this cause, this study develops a design methodology and framework using Simcenter Battery Design Studio® (BDS) and Bayesian optimization for design and optimization of cylindrical cell type 18650. The materials of the cathode are Nickel-Cobalt-Aluminum (NCA)/Nickel-Manganese-Cobalt-Aluminum (NMCA), anode is graphite, and electrolyte is Lithium hexafluorophosphate (LiPF6). Bayesian optimization has emerged as a powerful gradient-free optimization methodology to solve optimization problems that involve the evaluation of expensive black-box functions. The black-box functions are simulations of the cyclic performance test in Simcenter Battery Design Studio. The physics model used for this study is based on full system model described by Fuller and Newman. It uses Butler-Volmer Equation for ion-transportation across an interface and solvent diffusion model (Ploehn Model) for Aging of Lithium-Ion Battery Cells. The BDS model considers effects of SEI, cell electrode and microstructure dimensions, and charge-discharge rates to simulate battery degradation. Two objectives are optimized: maximization of the specific energy and minimization of the capacity fade. We perform global sensitivity analysis and see that thickness and porosity of the coating of the LIB electrodes that affect the objective functions the most. As such the design variables selected for this study are thickness and porosity of the electrodes. The thickness is restricted to vary from 22microns to 240microns and the porosity varies from 0.22 to 0.54. Two case studies are carried out using the above-mentioned objective functions and parameters. In the first study, cycling tests of 18650 NCA cathode Li-ion cells are simulated. The cells are charged and discharged using a constant 0.2C rate for 500 cycles. In the second case study a cathode active material more relevant to the electric vehicle industry, Nickel-Manganese-Cobalt-Aluminum (NMCA), is used. Here, the cells are cycled for 5 different charge-discharge scenarios to replicate charge-discharge scenario that an EVs battery module experiences. The results show that the design and optimization methodology can identify cells to satisfy the design objective that extend and improve the pareto front outside the original sampling plan for several practical charge-discharge scenarios which maximize energy density and minimize capacity fade.