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Li4Ti5O12 nanorods have been successfully synthesized via hydrothermal method using TiO2-B as titanium source and template. Such Li4Ti5O12 nanorods with sizes of 100-200 nm in diameter and 1-2 mu m in length can be observed. The L...
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Li4Ti5O12 nanorods have been successfully synthesized via hydrothermal method using TiO2-B as titanium source and template. Such Li4Ti5O12 nanorods with sizes of 100-200 nm in diameter and 1-2 mu m in length can be observed. The Li4Ti5O12 nanorods exhibit high discharge capacity of about 101.1 mAh g(-1) after 1000 cycles at 20C for the lithium ion battery anode. The Li4Ti5O12 nanorods also show excellent sodium storage performance, which have a reversible capacity of approximately 131.6 mAh g(-1) after 100 cycles at 0.1C. Based on the electrochemical performance, it is suggested that Li4Ti5O12 nanorods have a great potential for lithium and sodium ion battery that are available as large-scale storage devices for applications such as automotive and stationary energy storage. (C) 2015 Elsevier B.V. All rights reserved.
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A novel study was done using a designed 6.7L chamber for experiments under both enclosed and ventilated conditions. Under enclosed condition, for LIB (li-ion battery) above 0% SOC (state of charge), the cases ruptured. Above 50% S...
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A novel study was done using a designed 6.7L chamber for experiments under both enclosed and ventilated conditions. Under enclosed condition, for LIB (li-ion battery) above 0% SOC (state of charge), the cases ruptured. Above 50% SOC, an explosion was even triggered. Though the analysis of collected gas from the enclosed condition, the flammable gas (e.g., CH4, CO) concentration increased as SOC increased, even a gas explosion occurred. Under ventilation, the tendency of case rupture decreased and the gas explosion risk was reduced. Whether the case rupture occurred was depended on the rate of generated gas venting. Fick's Law was adopted to describe this phenomenon. It was found that the external pressure was the key factor impacting the case rupture. This work studied the LIB thermal runaway behaviors from a novel perspective, and provided a reference for the safety protection of the LIBs.
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Because of its intriguing properties, lithium has been extensively utilized in a wide number of industrial, scientific, and clinical applications. This article reviews the history of its discovery, its basic properties, and its cu...
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Because of its intriguing properties, lithium has been extensively utilized in a wide number of industrial, scientific, and clinical applications. This article reviews the history of its discovery, its basic properties, and its current mineralogical sources and surveys some of the more important uses of lithium today.
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Lithium-ion (rocking-chair) batteries with lithiated metal oxide cathodes and carbon anodes are finding use in many emerging electronic applications with current drains ranging from a few microamperes (e.g., memory backup, real-ti...
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Lithium-ion (rocking-chair) batteries with lithiated metal oxide cathodes and carbon anodes are finding use in many emerging electronic applications with current drains ranging from a few microamperes (e.g., memory backup, real-time clock, bridge function) to many milliamperes (e.g., laptop computers, phones, etc.). The majority of these applications (e.g., coin, cylindrical, prismatic cell configuration) require a steady low current with periodic high drain pulses. We have found that lithium-ion systems based on lithiated nickel oxide cathodes (LiNiO_2) and carbon anodes can be tailored for high capacity moderate rate or moderate capacity high rate applications. In the first instance, a graphitic carbon anode and ethylene carbonate-based electrolyte (e.g., ethylene carbonate-dimethyl carbonate (EC-DMC)) has proven effective while in the second case a petroleum coke anode and propylene carbonate-based electrolyte (e.g., propylene carbonate-dimethoxyethane (PC-DME)) look best. An unoptimized, experimental LiNiO_2/LiPF_6, EC-DMC/graphitic carbon, AA-cell has delivered 620 mAh at 0.1 mA cm~(-2) but the capacity then dropped to 535 mAh at 1 mA cm~(-2) and 375 mAh at 3 mA cm~(-2). Efforts are under way to improve the rate capabilities of cells incorporating graphitic carbon anodes. Initial results indicate that microfiber graphite, special electrolytes and in-house prepared LiM_xNi_(1-x)O_2 compounds will achieve the desired performance levels.
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A University of Surrey-led international team of researchers devised an improved methodology to push forward the detection sensitivity and spatial resolution for investigating the degradation mechanism of lithium-ion batteries.
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Real-time monitoring of the thermal characteristics of a lithium ion battery under electrical excitation, is a key requirement that underpins the safe operation of the battery; its reliability and life. Further, it facilitates the...
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Real-time monitoring of the thermal characteristics of a lithium ion battery under electrical excitation, is a key requirement that underpins the safe operation of the battery; its reliability and life. Further, it facilitates the design of many supporting elements of the battery system, including the thermal management strategy and the algorithms that comprise the battery management system. The novelty of this study is advanced distributed thermal monitoring from external to embedded measurement for future smart battery and management. Rayleigh scattering based optical fibre sensors are known to be robust and able to operate when immersed in electrolyte, they have a small physical size and are able to provide a measurement of temperature with a spatial resolution of circa 2.6 mm. The spatial distribution of the temperature profile, arising from the complexity and variations within the cell is investigated. The results show that the peak temperature between the cell core and surface, along the cell length can be as high as 9.7 ?& nbsp;for 1C discharge. This paper provides a detailed explanation of the cell modification method, instrumentation process and the fundamental principles of in-cell optical measurement. Results are presented and discussed within the context of enhanced battery thermal management and improved system safety that are applicable to the application of lithium ion batteries across a number of domains including automotive and aerospace.
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With the aim of finding new cathode materials for lithium--ion batteries, the synthesis of layered solid solutions with LiFe_yCo_1-yO_2 stoichiometries has been studied in this work. X-ray single phase products were obtained by a ...
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With the aim of finding new cathode materials for lithium--ion batteries, the synthesis of layered solid solutions with LiFe_yCo_1-yO_2 stoichiometries has been studied in this work. X-ray single phase products were obtained by a ceramic procedure for 0 ≤ y ≤ 0.2. The unit cell dimensions of the powdered solids increase with the iron content. The Rietveld analysis of a sample with y = 0.l using anisotropic thermal parameters led to K_BRAGG = 3'37. The hexagonal unit cell parameters of this solid were a = 2.827l(l) A and c = l4. l266(7) A. The site occupancy used in the Rietveld procedure was f (Fe~T_0.0086)_6c[Li_0.9868Fe~0_0.0046]3b[Li_0.0132co_0.9000Fe~0_0.0868 ]3aO_2 ac c ording to the intensity of the signals observed in the M6ssbauer spectrum. This consists of one intense (87/100) quadrupole split signal with isomer shift of ca. 0.3l6(3) mm/s is ascribable to Fe(lIl) replacing cobalt in the CoO_2 layers. Two weaker quadrupole signals result from small amounts of iron in octahedral 3b and pseudotetrahedral 6c sites of the LiO_2. layers. The presence of pseudotetrahedral iron puts obstacles to the lithium ion diffusivity. In consequence, the electrochemical spectra evidence an increased cell polarization as increases. The lithium extraction at the end of the first charge decreases with iron content, with a maximum of 0.6 Li per formula for y = 0.l. The introduction of nickel in the composition of these solids may be useful to improve the electrochemical performance of the solid solutions. Ternary systems show an improved electrochemical behaviour.
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In this work, a reduction roasting strategy was adopted to transform hematite into powerful anode materials to store lithium (Li), sodium (Na) and potassium (K). This strategy aimed to construct conductive porous structure on pris...
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In this work, a reduction roasting strategy was adopted to transform hematite into powerful anode materials to store lithium (Li), sodium (Na) and potassium (K). This strategy aimed to construct conductive porous structure on pristine hematite particles and could be generalized to other oxide anodes. The free volume of porous structure could cushion the volume changes, improve its accessibility to Li~+, Na~+, K~+ ions, and shorten ionic diffusion pathways. Therefore, these newly-designed anodes were discharged and charged to test their storage capacity, cycling stability as well as rate performances. Their cyclic voltam-metry curves and electrochemical impedance spectra were also measured to unravel ion-storage mechanisms.
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Electrochemical energy storage is of extraordinary importance for fulfilling the utilization of renewable and sustainable energy sources. There is an increasing demand for energy storage devices with high energy and power densitie...
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Electrochemical energy storage is of extraordinary importance for fulfilling the utilization of renewable and sustainable energy sources. There is an increasing demand for energy storage devices with high energy and power densities, prolonged stability, safety, and low cost. In the past decade, numerous research efforts have been devoted to achieving these requirements, especially in the design of advanced electrode materials. Hollow carbon spheres (HCS) derived nanomaterials combining the advantages of 3D HCS and porous structures have been considered as alternative electrode materials for advanced energy storage applications, due to their unique features such as high surface-to-volume ratios, encapsulation capability, together with outstanding chemical and thermal stability. In this review, the authors first present a comprehensive overview of the synthetic strategies of HCS, and elucidate the design and synthesis of HCS-derived nanomaterials including various types of HCS and their nanohybrids. Additionally, their significant roles as electrode materials for supercapacitors, lithium-ion or sodium-ion batteries, and sulfur hosts for lithium sulfur batteries are highlighted. Finally, current challenges in the synthesis of HCS and future directions in HCS-derived nanomaterials for energy storage applications are proposed.
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摘要 :Highlights?A new method for anode recycling and remanufacturing has been developed.?Recycled anodes showed performance similar to fresh material.?Recycled graphite shows evidence of prelithiation, with excellent first cycle capaci...
展开Highlights?A new method for anode recycling and remanufacturing has been developed.?Recycled anodes showed performance similar to fresh material.?Recycled graphite shows evidence of prelithiation, with excellent first cycle capacity.AbstractThis work demonstrates an experimental methodology for reusing anode material from end of life commercial lithium ion batteries (LiB) in order to create new LiB anodes. End-of-life LiB cells were safely opened and assessed as a source of anode material. Anode material extracted from LiB cells through a basic mechanical separation was cycled stably with minimal processing. The LiB cells produced with recovered anode material showed equivalent cycling capacity and lower first cycle capacity loss than similarly produced virgin graphite anodes, regardless of recycled material source or morphology, as shown by SEM imaging. The effects of some graphite pre-lithiation were seen, mainly in a lowered initial voltage of the cells before the first cycle. A methodology for scaling
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