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Synthesis Characterization And Improvement Of Li Excess Spinel And Layered Mn Based Cathode Materials For Lithium Ion Batteries
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Book Synopsis Synthesis, Characterization and Improvement of Li-excess Spinel and Layered Mn-based Cathode Materials for Lithium Ion Batteries by :
Download or read book Synthesis, Characterization and Improvement of Li-excess Spinel and Layered Mn-based Cathode Materials for Lithium Ion Batteries written by and published by . This book was released on 2013 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Batteries for Sustainability by : Ralph J. Brodd
Download or read book Batteries for Sustainability written by Ralph J. Brodd and published by Springer Science & Business Media. This book was released on 2012-12-12 with total page 513 pages. Available in PDF, EPUB and Kindle. Book excerpt: Batteries that can store electricity from solar and wind generation farms are a key component of a sustainable energy strategy. Featuring 15 peer-reviewed entries from the Encyclopedia of Sustainability Science and Technology, this book presents a wide range of battery types and components, from nanocarbons for supercapacitors to lead acid battery systems and technology. Worldwide experts provides a snapshot-in-time of the state-of-the art in battery-related R&D, with a particular focus on rechargeable batteries. Such batteries can store electrical energy generated by renewable energy sources such as solar, wind, and hydropower installations with high efficiency and release it on demand. They are efficient, non-polluting, self-contained devices, and their components can be recovered and used to recreate battery systems. Coverage also highlights the significant efforts currently underway to adapt battery technology to power cars, trucks and buses in order to eliminate pollution from petroleum combustion. Written for an audience of undergraduate and graduate students, researchers, and industry experts, Batteries for Sustainability is an invaluable one-stop reference to this essential area of energy technology.
Book Synopsis Development of Manganese-Based High Voltage Spinel and High Capacity Li-rich Layered Oxides for Improving Rate Capability as High Performance Cathode Materials in Lithium Ion Battery by : 金怡君
Download or read book Development of Manganese-Based High Voltage Spinel and High Capacity Li-rich Layered Oxides for Improving Rate Capability as High Performance Cathode Materials in Lithium Ion Battery written by 金怡君 and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Understanding the Capacity Fade Mechanisms of Spinel Manganese Oxide Cathodes and Improving Their Performance in Lithium Ion Batteries by : Won Chang Choi
Download or read book Understanding the Capacity Fade Mechanisms of Spinel Manganese Oxide Cathodes and Improving Their Performance in Lithium Ion Batteries written by Won Chang Choi and published by . This book was released on 2007 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lithium ion batteries have been successful in portable electronics market due to their high energy density, adopting the layered LiCoO2 as the cathode material in commercial lithium ion cells. However, increasing interest in lithium ion batteries for electric vehicle and hybrid electric vehicle applications requires alternative cathode materials due to the high cost, toxicity, and limited power capability of the layered LiCoO2 cathode. In this regard, spinel LiMn2O4 has become appealing as manganese is inexpensive and environmentally benign, but LiMn2O4 is plagued by severe capacity fade at elevated temperatures. This dissertation explores the factors that control and limit the electrochemical performance of spinel LiMn2O4 cathodes and focuses on improving the performance parameters such as the capacity, cyclability, and rate capability of various spinel cathodes derived from LiMn2O4. From a systematic investigation of a number of cationic and anionic (fluorine) substituted spinel oxide compositions, the improvements in electrochemical properties and performances are found to be due to the reduced manganese dissolution and suppressed lattice parameter difference between the two cubic phases formed during the charge-discharge process. Investigations focused on fluorine substitution reveal that spinel LiMn[subscript 2-yz]LiyZnzO[subscript 4-eta]F[subscript eta] oxyfluoride cathodes synthesized by solid-state reactions at 800 °C employing ZnF2 as a raw material and spinel LiMn[subscript 2-y-z]Li[subscript y]Ni[subscript z]O[subscript 4-eta]F[subscript eta] oxyfluoride cathodes synthesized by firing the cation-substituted LiMn[subscript 2-y-z]LiyNi[subscript z]O4 oxides with NH4HF2 at a moderate temperature of 450 °C show superior cyclability, increased capacity, reduced Mn dissolution, and excellent storage performance compared to the corresponding oxide analogs and the conventional LiMn2O4. Spinel-layered composite cathodes are found to exhibit better electrochemical performance with graphite anode when charged to 4.7 V in the first cycle followed by cycling at 4.3-3.5 V compared to the normal cycling at 4.3 - 3.5 V. The improved performance is explained to be due to the trapping of trace amounts of protons that may be present in the electrolyte within the layered oxide lattice during the first charge to 4.7 V and the consequent reduction in Mn dissolution. Electrochemical performances of 3 V spinel Li4Mn5O12 cathodes are also improved by fluorine substitution due to the suppression of the disproportionation of Li4Mn5O12 during synthesis and the formation of the Li2MnO3 phase.
Book Synopsis Materials for Lithium-Ion Batteries by : Christian Julien
Download or read book Materials for Lithium-Ion Batteries written by Christian Julien and published by Springer Science & Business Media. This book was released on 2000-10-31 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt: A lithium-ion battery comprises essentially three components: two intercalation compounds as positive and negative electrodes, separated by an ionic-electronic electrolyte. Each component is discussed in sufficient detail to give the practising engineer an understanding of the subject, providing guidance on the selection of suitable materials in actual applications. Each topic covered is written by an expert, reflecting many years of experience in research and applications. Each topic is provided with an extensive list of references, allowing easy access to further information. Readership: Research students and engineers seeking an expert review. Graduate courses in electrical drives can also be designed around the book by selecting sections for discussion. The coverage and treatment make the book indispensable for the lithium battery community.
Book Synopsis From Intrinsic to Extrinsic Design of Lithium-Ion Battery Layered Oxide Cathode Material Via Doping Strategies by : Chul-Ho Jung
Download or read book From Intrinsic to Extrinsic Design of Lithium-Ion Battery Layered Oxide Cathode Material Via Doping Strategies written by Chul-Ho Jung and published by Springer Nature. This book was released on 2022-10-20 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses the comprehensive understanding of Ni-rich layered oxide of lithium-ion batteries cathodes materials, especially focusing on the effect of dopant on the intrinsic and extrinsic effect to its host materials. This book can be divided into three parts, that is, 1. overall understanding of layered oxide system, 2. intrinsic effect of dopant on layered oxides, and 3. extrinsic effect of dopant on layered oxides. To truly understand and discover the fundamental solution (e.g. doping) to improve the Ni-rich layered oxides cathodic performance, understanding the foundation of layered oxide degradation mechanism is the key, thus, the first chapter focuses on discovering the true degradation mechanisms of layered oxides systems. Then, the second and third chapter deals with the effect of dopant on alleviating the fundamental degradation mechanism of Ni-rich layered oxides, which we believe is the first insight ever been provided. The content described in this book will provide research insight to develop high-performance Ni-rich layered oxide cathode materials and serve as a guide for those who study energy storage systems.
Book Synopsis Synthesis and Analysis of Spinel Cathode Materials for High Voltage Solid-state Lithium Batteries by : Anna Windmüller
Download or read book Synthesis and Analysis of Spinel Cathode Materials for High Voltage Solid-state Lithium Batteries written by Anna Windmüller and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Chemical, Structural, and Electrochemical Characterization of 5 V Spinel and Complex Layered Oxide Cathodes of Lithium Ion Batteries by : Arun Kumar Tiruvannamalai Annamalai
Download or read book Chemical, Structural, and Electrochemical Characterization of 5 V Spinel and Complex Layered Oxide Cathodes of Lithium Ion Batteries written by Arun Kumar Tiruvannamalai Annamalai and published by . This book was released on 2007 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lithium ion batteries have revolutionized the portable electronics market since their commercialization first by Sony Corporation in 1990. They are also being intensively pursued for electric and hybrid electric vehicle applications. Commercial lithium ion cells are currently made largely with the layered LiCoO2 cathode. However, only 50% of the theoretical capacity of LiCoO2 can be utilized in practical cells due to the chemical and structural instabilities at deep charge as well as safety concerns. These drawbacks together with the high cost and toxicity of Co have created enormous interest in alternative cathodes. In this regard, spinel LiMn2O4 has been investigated widely as Mn is inexpensive and environmentally benign. However, LiMn2O4 exhibits severe capacity fade on cycling, particularly at elevated temperatures. With an aim to overcome the capacity fading problems, several cationic substitutions to give LiMn[subscript 2-y]M[subscript y]O4 (M = Cr, Fe, Co, Ni, and Cu) have been pursued in the literature. Among the cation-substituted systems, LiMn[subscript 1.5]Ni[subscript 0.5]O4 has become attractive as it shows a high capacity of ~ 130 mAh/g (theoretical capacity: 147 mAh/g) at around 4.7 V. With an aim to improve the electrochemical performance of the 5 V LiMn[subscript 1.5]Ni[subscript 0.5]O4 spinel oxide, various cation-substituted LiMn[subscript 1.5-y]Ni[subscript 0.5-z]M[subscript y+z]O4 (M = Li, Mg, Fe, Co, and Zn) spinel oxides have been investigated by chemical lithium extraction. The cation-substituted LiMn[subscript 1.5-y]Ni[subscript 0.5-z]M[subscript y+z]O4 spinel oxides exhibit better cyclability and rate capability in the 5 V region compared to the unsubstituted LiMn[subscript 1.5]Ni[subscript 0.5]O4 cathodes although the degree of manganese dissolution does not vary significantly. The better electrochemical properties of LiMn[subscript 1.5-y]Ni]subscript 0.5-z]M[subscript y+z]O4 are found to be due to a smaller lattice parameter difference among the three cubic phases formed during the chargedischarge process. In addition, while the spinel Li[subscript 1-x]Mn[subscript 1.58]Ni[subscript 0.42]O4 was chemically stable, the spinel Li[subscript 1-x]Co2O4 was found to exhibit both proton insertion and oxygen loss at deep lithium extraction due to the chemical instability arising from a overlap of the Co[superscript 3+/4+]:3d band on the top of the O[superscript 2-]:2p band. The irreversible oxygen loss during the first charge and the consequent reversible capacities of the solid solutions between Li[Li[subscript 1/3]Mn[subscript 2/3]]O2 and Li[Co[subscript 1-y]Ni[subscript y]]O2 has been found to be determined by the amount of lithium in the transition metal layer of the O3 type layered structure. The lithium content in the transition metal layer is, however, sensitively influenced by the tendency of Ni[superscript 3+] to get reduced to Ni[superscript 2+] and the consequent volatilization of lithium during synthesis. Moreover, high Mn4+ content causes a decrease in oxygen mobility and loss. In addition, the chemically delithiated samples were found to adopt either the parent O3 type structure or the new P3 or O1 type structures depending upon the composition and synthesis temperature of the parent samples and the proton content inserted into the delithiated sample. In essence, the chemical and structural stabilities and the electrochemical performance factors of the layered (1-z) Li[Li[subscript 1/3]Mn[subscript 2/3]]O2 · (z) Li[Co[subscript 1-y]Ni[subscript y]]O2 solid solution cathodes are found to be maximized by optimizing the contents of the various ions.
Book Synopsis State-of-the-Art Materials Science in Belgium 2017 by : Dirk Poelman
Download or read book State-of-the-Art Materials Science in Belgium 2017 written by Dirk Poelman and published by MDPI. This book was released on 2018-10-17 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "State-of-the-Art Materials Science in Belgium 2017" that was published in Materials
Book Synopsis High-Resolution Transmission Electron Microscopy by : Peter Buseck
Download or read book High-Resolution Transmission Electron Microscopy written by Peter Buseck and published by Oxford University Press. This book was released on 1989-02-02 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an introduction to the fundamental concepts, techniques, and methods used for electron microscopy at high resolution in space, energy, and even in time. It delineates the theory of elastic scattering, which is most useful for spectroscopic and chemical analyses. There are also discussions of the theory and practice of image calculations, and applications of HRTEM to the study of solid surfaces, highly disordered materials, solid state chemistry, mineralogy, semiconductors and metals. Contributors include J. Cowley, J. Spence, P. Buseck, P. Self, and M.A. O'Keefe. Compiled by experts in the fields of geology, physics and chemistry, this comprehensive text will be the standard reference for years to come.
Book Synopsis Proceedings of the Symposium on Lithium Batteries by : Subbarao Surampudi
Download or read book Proceedings of the Symposium on Lithium Batteries written by Subbarao Surampudi and published by The Electrochemical Society. This book was released on 1999 with total page 594 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Comprehensive Energy Systems by : Ibrahim Dincer
Download or read book Comprehensive Energy Systems written by Ibrahim Dincer and published by Elsevier. This book was released on 2018-02-07 with total page 5543 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Energy Systems, Seven Volume Set provides a unified source of information covering the entire spectrum of energy, one of the most significant issues humanity has to face. This comprehensive book describes traditional and novel energy systems, from single generation to multi-generation, also covering theory and applications. In addition, it also presents high-level coverage on energy policies, strategies, environmental impacts and sustainable development. No other published work covers such breadth of topics in similar depth. High-level sections include Energy Fundamentals, Energy Materials, Energy Production, Energy Conversion, and Energy Management. Offers the most comprehensive resource available on the topic of energy systems Presents an authoritative resource authored and edited by leading experts in the field Consolidates information currently scattered in publications from different research fields (engineering as well as physics, chemistry, environmental sciences and economics), thus ensuring a common standard and language
Book Synopsis High Energy Density Cathode Active Materials for Lithium-ion Batteries by : Mehmet Nurullah Ates
Download or read book High Energy Density Cathode Active Materials for Lithium-ion Batteries written by Mehmet Nurullah Ates and published by . This book was released on 2015 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: Renewable energy sources such as solar energy, wind and hydroelectric power are increasingly being developed as essential energy alternatives to alleviate the deleterious effects of greenhouse gases in the globe. Large scale energy storage is an indispensable component of renewable energy sources and in this context, Li-ion batteries (LIBs), due to their high energy and power densities and long cycle life, have spurred great interest. Current Li-ion battery technology employs lithium cobalt oxide, LiCoO2, or one of its congeners, in which some of the Co is substituted with Ni and/or Mn as cathode active material. The deficiencies of LiCoO2 include: i-) low capacity with only 0.5 mole of Li+ is being reversibly used in the battery leading to 140 mAh/g discharge capacity at low to medium rates, ii-) high cost, and iii-) environmental concerns arising from the harmful physiological effects of Co metal. In order to overcome these deficiencies of LiCoO2, Li-rich layered metal dioxides, also known as layered-layered lithiated metal oxide composite compound, formulated as xLi2MnO3.(1-x)LiMO2 (M=Mn, Ni or Co), have been proposed recently. This dissertation presents an account of investigations leading to advanced materials which overcome the deficiencies of this class of high energy density Li-ion battery cathodes. Chapter 1 discusses the fundamental aspects of generic battery systems and elaborates on the current state of the art of rechargeable Li batteries. Chapter 2 deals with the discovery of the material 0.3Li2MnO3.0.7LiNi0.5Co0.5O2 (LLNC) that allowed us to conclude which segment of the lithium rich layered composite metal oxide is responsible for structural transformation from the layered to spinel phase during charge/discharge cycling. The crystal structure and electrochemistry of this new cathode active material in Li cells have been compared to that of 0.3Li2MnO3.0.7LiMn0.33Ni0.33Co0.33O2 (LLNMC). In LLNC, the removal of Mn from the LiMO2 (M=transition metal) segment allowed us to determine the identity of the manganese oxide moiety in it that triggers the layered to spinel conversion during cycling. The new material LLNC resists the layered to spinel structural transformation under conditions in which LLNMC does. X-ray diffraction (XRD) patterns revealed that both compounds, synthesized as approximately 300 nm crystals, have identical super lattice ordering attributed to Li2MnO3 existence. Using X-ray absorption (XAS) spectroscopy we elucidated the oxidation states of the K edges of Ni and Mn in the two materials with respect to different charge and discharge states. The XAS data along with electrochemical results revealed that Mn atoms are not present in the LiMO2 structural segment in LLNC. Electrochemical cycling data from Li cells further revealed that the absence of Mn in the LiMO2 segment significantly improves the rate capabilities of LLNC with good capacity maintenance during long term cycling. Removing the Mn from the LiMO2 segment of lithium rich layered metal oxides appears to be a holistic strategy for improving the structural robustness and rate capabilities of these high capacity cathode materials for Li-ion batteries. Chapter 3 examines the effect of alkali ion doping (Na+) into the cathode material of the composition 0.3Li2MnO3.0.7LiMn0.33Ni0.33Co0.33O2 (LLNMC). The 5 wt. % Na doped material, formulated as 0.3Li2MnO3.0.7Li0.97Na0.03Mn0.33Ni0.33Co0.33O2, was compared to its counterpart without Na doping. The discharge rate capability of the LLNMC was greatly improved at both room temperature and 50 0C with the Na doping. The Na doped material exhibited significantly higher electronic conductivity than its un-doped analog as evidenced by dc electronic conductivity data and AC impedance of Li cells. Charge/discharge cycling results of Li cells containing these cathode materials at 50 0C indicated that the voltage decay of LLNMC, accompanied by a layer to spinel structural conversion, was mitigated with Na doping. X-ray diffraction analysis revealed that ionic exchange of Na occurs upon contact of the cathode material with the electrolyte and produces a volume expansion of the crystal lattice which triggers a favorable metal (probably Ni) migration to Li depleted regions during electrochemical oxidation of Li2MnO3 in the first charge. X-ray absorption near edge spectra (XANES) data showed that Na doped NMC has better Ni reduction efficiency to provide higher rate capability. Extended X-ray absorption fine spectra (EXAFS) data supported this conclusion by showing that in the case of Na doped LLNMC, the structure has a larger crystal cage allowing for better metal migration into the Li depleted regions located in the layered unit cell of C2/m space group. XANES of Mn K-edge supported by pre-edge analysis also revealed that during charging of the electrode, the Na doped NMC was oxidized to a higher Mn valence state compared to its undoped counterpart. The results of a comprehensive electrochemical and structural investigations of a wide range of lithium rich layered metal oxide cathode active materials, xLi2MnO3.(1-x)LiMnaNibCocO2 (where x, a, b and c vary) are reported in Chapter 4. In order to identify the cathode material having the optimum Li cell performance we first varied the ratio between Li2MnO3 and LiMO2 segments of the composite oxides while maintaining the same metal ratio residing within their LiMO2 segments. The materials with the overall composition 0.5Li2MnO3.0.5LiMO2 containing 0.5 mole of Li2MnO3 per mole of the composite metal oxide were found to be the optimum in terms of electrochemical performance. The electrochemical properties of these materials were further tuned by changing the relative amounts of Mn, Ni and Co in the LiMO2 segment to produce xLi2MnO3.(1-x)LiMn0.50Ni0.35Co0.15O2 with enhanced capacities and rate capabilities. The rate capability of the lithium rich compound in which x=0.3 was further increased by preparing electrodes with about 2 weight-percent multiwall carbon nanotube in the electrode. Lithium cells prepared with such electrodes were cycled at the 4C rate with little fade in capacity for over one hundred cycles. In Chapter 5, the results of a new synthesis technique, called self-ignition combustion (SIC), that dramatically enhanced the rate capabilities of a lithium rich layered metal oxide compound we prepared are discussed. In this chapter, we report a high rate Li-rich layered manganese nickel cobalt (MNC) cathode material of the composition 0.5Li2MnO3.0.5LiMn0.5Ni0.35Co 0.15O2, termed SIC-MNC cathode material for Li-ion batteries with discharge capacities of 200, 250, and 290 mAh/g at C, C/4 and C/20 rates, respectively. This high rate discharge performance combined with little capacity fade during long term cycling is unprecedented for this class of Li-ion cathode materials. The exceptional electrochemistry of the Li-rich SIC-MNC in Li-ion cells is attributed to its open porous morphology and high electronic conductivity. The structure of the material investigated by means of X-ray diffraction, High Resolution Transmission Electron Microscopy (HRTEM) and X-ray absorption spectroscopy combined with electrochemical data revealed that the porous morphology was effective in allowing electrolyte penetration through the particle grains to provide high Li+ transport in tandem with high electronic conductivity for high rate discharge. Extended cycling behavior and structural phase transition of the new material were further examined through Field Emission Scanning Electron Microscopy (FESEM), XRD, XAS and HRTEM. The new SIC-MNC cathode represents the long sought after next generation cathode material for Li-ion batteries with pecific energy exceeding 400 Wh/kg or energy density over 1000 Wh/l. The conclusion and future directions are presented in Chapter 6.
Book Synopsis Optimization of Layered Battery Cathode Materials Synthesized Via Spray Pyrolysis by : Miklós Lengyel
Download or read book Optimization of Layered Battery Cathode Materials Synthesized Via Spray Pyrolysis written by Miklós Lengyel and published by . This book was released on 2014 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rapid advancements of techniques for the synthesis of Li-ion battery materials are critically needed to address the requirement of a clean and efficient transportation sector. The current research serves this goal by developing an approach to producing layered cathode materials with superior electrochemical performance for electric vehicles (EVs). Current widespread application of EVs is primarily limited by their short range and their high price, which is primarily driven by the cost of the battery pack. The cost of the battery pack is driven by the cost of the cathode material that empowers it. Novel, high throughput and inexpensive synthesis methods delivering nanostructured materials are a key to meeting these requirements. The synthesis techniques need to be scalable, robust, and reproducible while producing high-density materials for lithium ion batteries. To this end we advance spray pyrolysis for the synthesis of the layered NMC composite materials, which are showing high promise as a cathode material. Spray pyrolysis produces high purity materials, and the limited number of process parameters allows for low cost and excellent control over product properties and outstanding batch-to-batch reproducibility. Layered Li-excess composite materials show nearly twice the capacity of commercial LiCoO2 cells. The materials are inexpensive, have improved safety characteristics and long cycle life. Yet, as recently demonstrated, the materials suffer from an inherent layered-spinel phase change. This leads to a voltage fade over extended cycling, and this shortcoming needs to be addressed before commercial implementation is feasible. In this work spherical-shape layered xLi2MnO3*(1-x)LiNi1/3Mn1/3Co1/3O2 composites were synthesized. The relationship between composition and material stability under different synthesis conditions (350 °C - 800°C reactor temperatures, 0.5 - 2.5 M concentration, 6.6 - 10.4 lpm flow rates) were explored. We found that from among the compositions corresponding to x = 0.3, 0.5 and 0.7, the composition for x = 0.3, or Li1.14Mn0.46Ni0.2Co0.2O2, provides improved stability and the least amount of voltage fade while displaying capacities around 190 mAhg-1 after 100 cycles at C/10 rate at room temperature. At the same time, for x = 0.5, or Li1.2Mn0.54Ni0.13Co0.13O2, the material delivers 205-210 mAhg-1 discharge capacities at C/3 rate at room temperature after 100 cycles, but displays more voltage fade over cycling. This work demonstrated that the major process parameters (flow rate, reactor synthesis temperature and concentration) can be accurately controlled and the synthesis method is robust. The reproducibility of the process was evaluated using charge and discharge tests and the standard deviation for cycling tests was 4 mAhg-1 at C/3 rate based on 4 batches produced under identical conditions on different dates. This indicates excellent batch-to-batch reproducibility. Post-synthesis annealing temperature optimization was performed for cobalt doped samples at 850 °C and 900 °C and we found that annealing for 900 °C for 2 hours improves the cycling stability of the samples. We evaluated the effect of lithium content between 3.3 wt% excess and 3.3 wt% deficiency and annealed the materials for 2, 5 and 20 hours at 900 °C. This helped develop a fundamental understanding between surface area and internal structural changes related to the Li2MnO3 structural component of the materials. Spray pyrolysis uniquely allows for the accurate control of stoichiometry and composition to trace contaminant level at these concentrations. Furthermore, through a collaborative research between Argonne National Laboratory, X-Tend Energy, LLC and Washington University in St. Louis a novel, highly scalable patent-pending slurry spray pyrolysis process was developed, which allows the production of battery materials with excellent electrochemical performance and provides a general platform for oxide materials at greater than 50 gh-1 scale. This unique process is the only known solution to the hollow sphere issue that has challenged spray pyrolysis synthesis for decades, namely producing particles greater than 2[mu]m size with a solid (non-hollow) but porous interior morphology. Tap densities greater than 1.0 gcm-3 are achieved at greater than 50 gh-1 scale as compared to 0.4-0.6 gcm-3 at 2 gh-1 scale. Li1.2Mn0.54Ni0.13Co0.13O2 produced by this novel process delivered ~205 mAhg-1 discharge capacity after 100 cycles at C/3 rate at room temperature, reproducing the electrochemical performance of the laboratory scale synthesis process and meeting or exceeding the performing of materials produced by co-precipitation. Voltage fade was addressed in the latter part of the work by varying the compositional ratio and using trace elemental doping. Results demonstrated for the first time that by selectively doping the xLi2MnO3*(1-x)LiNi1/3Mn1/3Co1/3O2 materials voltage fade can be reduced, as indicated by dQ/dV curves. The spray pyrolysis process for xLi2MnO3*(1-x)LiNi1/3Mn1/3Co1/3O2 materials, in particular for layered Li1.2Mn0.54Ni0.13Co0.13O2 displayed the highest capacity (c.a. 205-210 mAhg-1 after 100 cycles at C/3 rate at room temperature) among all cathode materials synthesized via spray pyrolysis to date.
Book Synopsis Magnetic, Electronic, and Electrochemical Properties of High-voltage Spinel Cathodes for Lithium-ion Batteries by : Zachary Moorhead-Rosenberg
Download or read book Magnetic, Electronic, and Electrochemical Properties of High-voltage Spinel Cathodes for Lithium-ion Batteries written by Zachary Moorhead-Rosenberg and published by . This book was released on 2015 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lithium-ion technology has revolutionized the electronics and electric vehicle industry in the past two decades. First commercialized by Sony in 1991, the lithium-ion battery is composed of three main components: (i) the cathode, (ii) the anode, and (iii) the electrolyte. Graphitic carbon remains the most widely used anode material due to its low voltage vs. the Li/Li+ redox couple and high specific capacity. However, there are several popular cathode materials, including layered oxides, spinel oxides, and polyanion materials. In an effort to increase the energy density of lithium-ion batteries, much focus is given to improving the gravimetric charge capacity and the overall cell voltage. The latter must be accomplished by employing high-voltage cathodes, the most promising of which is the lithium manganese nickel oxide spinel with a specific capacity of 146 mAh/g and a redox voltage of 4.7 V vs. Li/Li+. However, there are still several problems with this material that must be understood and overcome in order to develop high-voltage spinel as a viable commercial cathode. Physical property measurements can reveal the underlying electronic and atomic interactions in the solid in order to better understand high-voltage spinel and its odd behavior. Novel magnetic techniques have been developed, which reliably indicate the degree of Mn-Ni ordering and quantitative determination of the concentration of the Mn3+ ion. Measurements of several physical properties as a function of lithium content were also undertaken to determine the effects of Mn-Ni ordering on the electronic conductivity and the importance of electron-ion interactions. In addition to understanding the physical properties of high voltage spinel, the understanding of the solid state chemistry and unique structure was utilized to realize a new full cell construction technique. The spinel structure offers a unique way to deal with first cycle irreversible capacity loss in full cells stemming from solid-electrolyte interphase (SEI) layer growth on the anode surface. To that end, a novel microwave-assisted chemical lithiation process was developed using non-toxic and air-stable chemicals. New composite anode chemistry was combined with a pre-lithiated spinel cathode to demonstrate the feasibility of this approach to realizing practical next-generation Li-ion cells.
Book Synopsis Studies on Anionic Redox in Li-Rich Cathode Materials of Li-Ion Batteries by : Biao Li
Download or read book Studies on Anionic Redox in Li-Rich Cathode Materials of Li-Ion Batteries written by Biao Li and published by Springer. This book was released on 2018-12-13 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents studies and discussions on anionic redox, which can be used to boost the capacities of cathode electrodes by providing extra electron transfer. This theoretically and practically significant book facilitates the implementation of anionic redox in electrodes for real-world use and accelerates the development of high-energy-density lithium-ion batteries. Lithium-ion batteries, as energy storage systems, are playing a more and more important role in powering modern society. However, their energy density is still limited by the low specific capacity of the cathode electrodes. Based on a profound understanding of band theory, the author has achieved considerable advances in tuning the redox process of lithium-rich electrodes to obtain enhanced electrochemical performance, identifying both the stability mechanism of anionic redox in lithium-rich cathode materials, and its activation mechanism in these electrode systems.
Download or read book Bibliography written by Pierre Villars and published by Walter de Gruyter. This book was released on 2012-12-21 with total page 1827 pages. Available in PDF, EPUB and Kindle. Book excerpt: By browsing about 10 000 000 scientific articles of over 200 major journals mainly in a 'cover to cover approach' some 200 000 publications were selected. The extracted data is part of the following fundamental material research fields: crystal structures (S), phase diagrams (also called constitution) (C) and the comprehensive field of intrinsic physical properties (P). This work has been done systematically starting with the literature going back to 1900. The above mentioned research field codes (S, C, P) as well as the chemical systems investigated in each publication were included in the present work. The aim of the Inorganic Substances Bibliography is to provide researchers with a comprehensive compilation of all up to now published scientific publications on inorganic systems in only three handy volumes.
