Solution Method Preparation and Electrochemical Characteristics Analysis of Spinel LiMn2O4 as the Cathode Materials in Lithium Ion Batteries

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Total Pages : 214 pages
Book Rating : 4.:/5 (768 download)

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Book Synopsis Solution Method Preparation and Electrochemical Characteristics Analysis of Spinel LiMn2O4 as the Cathode Materials in Lithium Ion Batteries by : 林樂

Download or read book Solution Method Preparation and Electrochemical Characteristics Analysis of Spinel LiMn2O4 as the Cathode Materials in Lithium Ion Batteries written by 林樂 and published by . This book was released on 2001 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Understanding the Electrochemical Properties and Safety Characteristics of Spinel Cathodes for Lithium-ion Batteries

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ISBN 13 :
Total Pages : 230 pages
Book Rating : 4.:/5 (861 download)

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Book Synopsis Understanding the Electrochemical Properties and Safety Characteristics of Spinel Cathodes for Lithium-ion Batteries by : Katharine Rose Chemelewski

Download or read book Understanding the Electrochemical Properties and Safety Characteristics of Spinel Cathodes for Lithium-ion Batteries written by Katharine Rose Chemelewski and published by . This book was released on 2013 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Manganese spinel cathodes LiMn2O4 offer the advantage of a strong, edge-shared octahedral framework with fast, 3-dimensional Li+-ion conduction. To better understand the safety of these materials, the thermal stability characteristics of spinel oxide and oxyfluoride cathodes Li[subscript 1.1]Mn[subscript 1.9-y]M[subscript y]O4[subscript-z]F[subscript z] (M = Ni and Al, 0 ≤ y ≤ 0.3, and 0 ≤ z ≤ 0.2) have been investigated systematically. The thermal characteristics are assessed in terms of the onset temperature and reaction enthalpy for the exothermic reaction. The thermal stability increases with decreasing lithium content in the cathode in the charged state. High-voltage spinel cathodes LiMn[subscript 1.5]Ni[subscript 0.5]O4 are promising candidates for electric vehicles and stationary storage of electricity produced by renewable energies due to their high power capability. However, widespread adoption of this high-voltage spinel cathode is hampered by severe capacity fade resulting from aggressive reaction with the electrolyte to form a thick solid-electrolyte interphase (SEI) layer. The synthesis conditions of the co-precipitation method are found to influence the microstructure and morphology through nucleation and growth of crystals in solution. Two samples prepared by similar wet-chemical routes have been characterized by microscopy and electrochemical methods to determine the role of microstructure and morphology on the electrochemical performance. It is found that the surface crystal planes play a key role in the capacity retention and rate performance. In order to achieve consistent electrochemical properties essential for the commercialization of the high-voltage spinel cathode LiMn[subscript1.5]Ni[subscript 0.5]O4, the relationship between cation ordering, presence of impurity phase, and particle morphology must be elucidated. Accordingly, comparison of the stoichiometric LiMn[subscript1.5]Ni[subscript 0.5]O4 cathodes with a Mn/Ni ratio of 3.0 prepared by different methods having varying morphologies and degrees of cation ordering is presented. It is found that although an increase in the degree of cation ordering decreases the rate capability, the crystallographic planes in contact with the electrolyte have a dominant effect on the electrochemical properties. To examine the effect of cation substitution on morphology, an investigation of the nucleation and growth of doped co-precipitated mixed-metal hydroxide precursor particles and the resulting stabilization of preferred crystallographic surface planes in the final spinel samples are presented. It is found that doping with certain cations stabilizes the growth of low-energy (111) surface planes, facilitating a long cycle life and fast high-rate performance. With an aim to develop a better understanding of the factors influencing the electrochemical properties, a systematic investigation of LiMn[subscript 1.5]Ni[subscript0.5-x]M[subscript x]O4 (M = Cu and Zn and x = 0.08 and 0.16), in which Ni2+ ions are substituted by divalent Cu2+ and Zn2+ ions, is presented. It is found that although both Zn and Cu are divalent with ionic radii similar to that of Ni2+, they behave quite differently with respect to cation ordering and site occupancy, and higher levels of doping leads to distinct differences in cycling and rate performances.

Chemical, Structural, and Electrochemical Characterization of 5 V Spinel and Complex Layered Oxide Cathodes of Lithium Ion Batteries

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Total Pages : 292 pages
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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.

Synthesis and Analysis of Spinel Cathode Materials for High Voltage Solid-state Lithium Batteries

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ISBN 13 : 9783958063969
Total Pages : pages
Book Rating : 4.0/5 (639 download)

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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:

LiMn2O4-Based Cathode Materials for Lithium Ion Batteries Prepared by the Pechini Process

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Total Pages : 180 pages
Book Rating : 4.:/5 (187 download)

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Book Synopsis LiMn2O4-Based Cathode Materials for Lithium Ion Batteries Prepared by the Pechini Process by : Wen Liu

Download or read book LiMn2O4-Based Cathode Materials for Lithium Ion Batteries Prepared by the Pechini Process written by Wen Liu and published by . This book was released on 1997 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Magnetic, Electronic, and Electrochemical Properties of High-voltage Spinel Cathodes for Lithium-ion Batteries

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Total Pages : 312 pages
Book Rating : 4.:/5 (921 download)

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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.

Preparation and Characterization of Cathode Materials for Lithium Ion Batteries Using Sol-gel Method

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ISBN 13 :
Total Pages : 36 pages
Book Rating : 4.:/5 (96 download)

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Book Synopsis Preparation and Characterization of Cathode Materials for Lithium Ion Batteries Using Sol-gel Method by : Ramanan A. V. Pattabiraman

Download or read book Preparation and Characterization of Cathode Materials for Lithium Ion Batteries Using Sol-gel Method written by Ramanan A. V. Pattabiraman and published by . This book was released on 2010 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Facile Preparation and Electrochemical Performances of LiMn2O4/Li1.2(Mn0.56Ni0.16Co0.08)O2 Blend Cathode Materials for Lithium Ion Battery

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Total Pages : 0 pages
Book Rating : 4.:/5 (14 download)

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Book Synopsis Facile Preparation and Electrochemical Performances of LiMn2O4/Li1.2(Mn0.56Ni0.16Co0.08)O2 Blend Cathode Materials for Lithium Ion Battery by :

Download or read book Facile Preparation and Electrochemical Performances of LiMn2O4/Li1.2(Mn0.56Ni0.16Co0.08)O2 Blend Cathode Materials for Lithium Ion Battery written by and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Modeling, Synthesis and Characterization of LiMn2O4 Spinels

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Total Pages : 3 pages
Book Rating : 4.:/5 (684 download)

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Book Synopsis Modeling, Synthesis and Characterization of LiMn2O4 Spinels by :

Download or read book Modeling, Synthesis and Characterization of LiMn2O4 Spinels written by and published by . This book was released on 1997 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors report on an integrated program to understand the fundamentals of LiMn2O4 performance as a cathode for lithium ion rechargeable batteries. Specifically, this program is designed to address the effects of doping on the crystal chemistry, lattice constants, and electrochemical performance. The work is being expanded to include studies on LiCoO2 and LiNiO2.

An Investigation of the Morphological and Electrochemical Properties of Spinel Cathode Oxide Materials Used in Li-ion Batteries

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Total Pages : 482 pages
Book Rating : 4.:/5 (1 download)

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Book Synopsis An Investigation of the Morphological and Electrochemical Properties of Spinel Cathode Oxide Materials Used in Li-ion Batteries by : Charmelle Snyders

Download or read book An Investigation of the Morphological and Electrochemical Properties of Spinel Cathode Oxide Materials Used in Li-ion Batteries written by Charmelle Snyders and published by . This book was released on 2016 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt:

State-of-the-Art Materials Science in Belgium 2017

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Publisher : MDPI
ISBN 13 : 3038972428
Total Pages : 300 pages
Book Rating : 4.0/5 (389 download)

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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

Low Temperature Processing and Electrochemical Characterization of Phosphate Based Cathode Materials and Electrolytes for Li-ion Batteries

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ISBN 13 : 9783844014051
Total Pages : 166 pages
Book Rating : 4.0/5 (14 download)

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Book Synopsis Low Temperature Processing and Electrochemical Characterization of Phosphate Based Cathode Materials and Electrolytes for Li-ion Batteries by : Madhav Singh

Download or read book Low Temperature Processing and Electrochemical Characterization of Phosphate Based Cathode Materials and Electrolytes for Li-ion Batteries written by Madhav Singh and published by . This book was released on 2012-10-21 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Design, Synthesis and Properties of High-voltage Spinel Cathode and Hybrid Anode Materials for Lithium-ion Batteries

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Total Pages : pages
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Book Synopsis Design, Synthesis and Properties of High-voltage Spinel Cathode and Hybrid Anode Materials for Lithium-ion Batteries by : Haidong Liu

Download or read book Design, Synthesis and Properties of High-voltage Spinel Cathode and Hybrid Anode Materials for Lithium-ion Batteries written by Haidong Liu and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Synthesis and Characterization of Lini0. 6mn0. 35co0. 05o2 and Li2fesio4/C As Electrodes for Rechargeable Lithium Ion Battery

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ISBN 13 : 9781361298015
Total Pages : pages
Book Rating : 4.2/5 (98 download)

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Book Synopsis Synthesis and Characterization of Lini0. 6mn0. 35co0. 05o2 and Li2fesio4/C As Electrodes for Rechargeable Lithium Ion Battery by : Pengda Hong

Download or read book Synthesis and Characterization of Lini0. 6mn0. 35co0. 05o2 and Li2fesio4/C As Electrodes for Rechargeable Lithium Ion Battery written by Pengda Hong and published by . This book was released on 2017-01-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Synthesis and characterization of LiNi0.6Mn0.35Co0.05O2 and Li2FeSiO4/C as electrodes for rechargeable lithium ion battery" by Pengda, Hong, 洪鹏达, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: The rechargeable lithium ion batteries (LIB) are playing increasingly important roles in powering portal commercial electronic devices. They are also the potential power sources of electric mobile vehicles. The first kind of the cathode materials, LiXCoO2, was commercialized by Sony Company in 1980s, and it is still widely used today in LIB. However, the high cost of cobalt source, its environmental unfriendliness and the safety issue of LiXCoO2 have hindered its widespread usage today. Searching for alternative cathode materials with low cost of the precursors, being environmentally benign and more stable in usage has become a hot topic in LIB research and development. In the first part of this study, lithium nickel manganese cobalt oxide (LiNi0.6Mn0.35Co0.05O2) is studied as the electrode. The materials are synthesized at high temperatures by solid state reaction method. The effect of synthesis temperature on the electrochemical performance is investigated, where characterizations by, for example, X-ray diffraction (XRD) and scanning electron microscopy (SEM), for particle size distribution, specific surface area, and charge-discharge property, are done over samples prepared at different conditions for comparison. The electrochemical tests of the rechargeable Li ion batteries using LiNi0.6Mn0.35Co0.05 cathode prepared at optimum conditions are carried out in various voltage ranges, at different discharge rates and at high temperature. In another set of experiments, the material is adopted as anode with lithium foil as the cathode, and its capacitance is tested. In the second part of this study, the iron based cathode material is investigated. Lithium iron orthosilicate with carbon coating is synthesized at 700℃ by solid state reaction, which is assisted by high energy ball milling. Characterizations are done for discharge capacities of the samples with different carbon weight ratio coatings. DOI: 10.5353/th_b4715029 Subjects: Lithium ion batteries Cathodes Lithium compounds - Synthesis Cobalt compounds - Synthesis Manganese compounds - Synthesis Silicon compounds - Synthesis Iron compounds - Synthesis

Effect of Processing Routes on Structural/Electrochemical Properties of Mn-based Spinel Cathode for Li Batteries Applications

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Total Pages : 84 pages
Book Rating : 4.:/5 (18 download)

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Book Synopsis Effect of Processing Routes on Structural/Electrochemical Properties of Mn-based Spinel Cathode for Li Batteries Applications by : 夏曉萍

Download or read book Effect of Processing Routes on Structural/Electrochemical Properties of Mn-based Spinel Cathode for Li Batteries Applications written by 夏曉萍 and published by . This book was released on 2018 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Nanowires

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Publisher : BoD – Books on Demand
ISBN 13 : 1789859050
Total Pages : 122 pages
Book Rating : 4.7/5 (898 download)

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Book Synopsis Nanowires by : Simas Rackauskas

Download or read book Nanowires written by Simas Rackauskas and published by BoD – Books on Demand. This book was released on 2019-04-10 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanowires are attracting wide scientific interest due to the unique properties associated with their one-dimensional geometry. Developments in the understanding of the fundamental principles of the nanowire growth mechanisms and mastering functionalization provide tools to control crystal structure, morphology, and the interactions at the material interface, and create characteristics that are superior to those of planar geometries. This book provides a comprehensive overview of the most important developments in the field of nanowires, starting from their synthesis, discussing properties, and finalizing with nanowire applications. The book consists of two parts: the first is devoted to the synthesis of nanowires and characterization, and the second investigates the properties of nanowires and their applications in future devices.

Low-temperature Synthesis and Electrochemical Properties of Aliovalently-doped Phosphates and Spinel Oxides

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ISBN 13 :
Total Pages : 260 pages
Book Rating : 4.:/5 (882 download)

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Book Synopsis Low-temperature Synthesis and Electrochemical Properties of Aliovalently-doped Phosphates and Spinel Oxides by : Arturo Gutierrez

Download or read book Low-temperature Synthesis and Electrochemical Properties of Aliovalently-doped Phosphates and Spinel Oxides written by Arturo Gutierrez and published by . This book was released on 2014 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lithium-ion batteries are being intensely pursued as energy storage devices because they provide higher energy and power densities compared to other battery systems such as lead-acid and nickel-metal hydride batteries. This dissertation (i) explores the use of a low-temperature microwave-assisted synthesis process to obtain aliovalently-doped lithium transition-metal phosphates and lower-valent vanadium oxide spinels, some of which are difficult to obtain by conventional high-temperature processes, and (ii) presents an investigation of the electrochemical properties of the aliovantly-doped phosphate cathodes and doped lithium manganese oxide and oxyfluoride spinel cathodes in lithium-ion batteries. Following the introduction and general experimental procedures, respectively, in Chapters 1 and 2, Chapter 3 first focuses on understanding of how the inductive effect and structural features in lithium transition-metal borate, silicate, and phosphate cathodes affect the M2+ʹ3+redox energies. It is found that the magnitude of the voltages delivered by the polyanion cathodes can be predicted based simply on the coordination of the transition-metal ion. Furthermore, the differences in the voltages delivered by the phosphates and pyrophosphates are explained by considering the resonance structures and their contribution to the covalency of the polyanion. Chapter 4 presents a low-temperature microwave-assisted solvothermal process to substitute 20 atom % V3+ for Mn2+ in LiMnPO4. It is shown that the solubility of vanadium in LiMnPO4 decreases upon heating the doped samples to ≥ 575 °C, demonstrating the importance of employing a low-temperature process to achieve aliovalent doping in LiMnPO4. It is further demonstrated that by increasing the vanadium content in the material, the discharge capacity in the first cycle could be increased without any additional carbon coating. Subsequent X-ray absorption spectroscopy data reveal that the better performance is facilitated by enhanced Mn-O hybridization upon incorporating vanadium into the lattice. Chapter 5 explores the influence of various factors, such as the oxidation state of Mn, electronegativity of the dopant cation Mn+, and the dissociation energy of M-O bond, on the electrochemical properties of cation-doped oxide and oxyfluoride spinel cathodes. As an extension, Chapter 6 presents the effect of processing conditions on the surface concentration of the dopant cation Mn+. Chapter 7 presents an extension of the low-temperature microwave-assisted synthesis process to obtain AV2O4 (Mg, Fe, Mn, and Co) spinel oxides. The method is remarkably effective in reducing the synthesis time and energy use due to the efficiency of dielectric heating compared to conventional heating. The ability to access V3+ is facilitated by the relative positions of the energy levels of the cations in solution, which is lower than that in the solid, and the use of a strong reducing solvent like TEG. Finally, Chapter 8 provides a summary of the salient findings in this dissertation.