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"Union Carbide Corporation Nuclear Division operating the Oak Ridge Gaseous Diffusion Plant, Oak Ridge Y-12 Plant, Oak Ridge National Laboratory, and Paducah Gaseous Diffusion Plant for the Atomic Energy Commission under U.S. government contract W-7405-eng-26." ; "Date Issued: June 5, 1964" ; "April 24, 1964" ; Y-1470-C ; "Chemistry; TID-4500 (29th Edition)." ; Includes bibliographical references (p. 11). ; U.S. Atomic Energy Commission ; Mode of access: Internet.

We report surface chemical cation composition analysis of high quality superconducting LiTi$_{2}$O$_{4}$ thin films, grown epitaxially on MgAl$_{2}$O$_{4}$ (111) substrates by pulsed laser deposition. The superconducting transition temperature of the films was ~13.8 K. Surface chemical composition is crucial for the formation of a good metal/insulator interface for integrating LiTi$_{2}$O$_{4}$ into full-oxide spin-filtering devices in order to minimize the formation of structural defects and increase the spin polarisation efficiency. In consideration of this, we report a detailed angle resolved x-ray photoelectron spectroscopy analysis. Results show Li segregation at the surface of LiTi$_{2}$O$_{4}$ films. We attribute this process due to outdiffusion of Li toward the outermost LiTi$_{2}$O$_{4}$ layers. ; The research leading to these results has received funding from the European Union Seventh Framework Programme ([FP7/2007–2013] [FP7/2007–2011]) under Grant agreement 316657 (SpinIcur), the European Research Council AdG (291442 "Superspin"), European Research Council AdG (247276 "NOVOX") and the EPSRC (Equipment Account Grant EP/K035282/1). ; This is the final version of the article. It first appeared from Elsevier via https://doi.org/10.1016/j.jcrysgro.2016.09.017

Lithium-ion batteries currently equip portable electronic devices, such as smartphones and laptops, and are the choice to power electric vehicles. The scarcity of raw materials in nature, however, has required the development of new technologies and the ternary lithium compound LiNi1/3Mn1/3Co1/3O2 has stood out as an alternative for replacing part of the cobalt in LiCoO2 by nickel and manganese, which are more abundant, reducing the electrode's cost. The sol-gel route for synthesis of ternary electrode materials has been widely used, but it faces problems of volumetric expansion due to the decomposition of organic material during calcination. To improve the synthesis of the ternary compound, a modified sol-gel route with control of the heating kinetics in the pre-calcination step and without pH control was investigated in this study. The compound was analyzed by X-ray diffraction, Rietveld refinement, Fourier transform infrared absorption spectroscopy, and Raman that showed the purification of the ternary phase with appropriate crystallinity for application as electrode in batteries from 700 ºC. In conclusion, ternary synthesis with rate control during heat treatment may be a useful alternative for industrial scale-up production.

The effect of various concentrations of lithium sulfate on human erythrocytes in vitro has been studied. It has been shown that the effect of lithium salt in maximum pharmacological and toxic concentrations on cells leads to a modification of the physicochemical state of membrane-bound proteins and lipids. It was found that in human erythrocytes exposed to lithium ions, there is a decrease in the activity of membrane-bound acetylcholinesterase and methgemoglobin reductase, as well as a change in the microviscosity of the lipid bilayer of membranes. The results obtained can be used to create a cell test system for assessing the toxicity of lithium compounds.

Im Kontext der Elektromobilität besitzt die Pouchzelle durch ihre hohe volumetrische und gravimetrische Energiedichte hervorragende Applikationseigenschaften. Die Herstellung des Elektroden-Separator-Zellverbunds ist durch die sequenzielle Abfolge von Zu- und Rückstellbewegungen – zurzeit ausgeführt von Industrierobotern – ineffizient und kostentreibend. Vorgestellt wird das Konzept einer vollautomatisierten Anlage mit einer kontinuierlichen Verfahrensführung ohne Verwendung von Zu- und Rückstellbewegungen.
 
In the context of electromobility, the pouch cell has distinctive advantages due to its high volumetric and gravimetric energy density. Manufacturing the electrode-separator-compound is inefficient and partly responsible for high manufacturing costs due to the required sequential setting and resetting movements of industrial robots carrying them out. A concept of a fully automated machine is presented, which uses a continuous process flow and avoids setting and resetting movements.

In order to achieve the CO2 emission targets of the German Government, it is necessary to significantly reduce the CO2 emissions of passenger cars. The substitution of the conventional internal combustion engine by a battery electric drive is a suitable method for this purpose. For a high economical use of such vehicles, high range and low cost are of great importance. Both criteria can be achieved by the use of high-voltage cathode materials in the lithium ion batteries used. However, since these materials show a strong aging, their commercial use is not yet possible. The dominant aging mechanism in high-voltage cathode materials is not yet clearly described in the literature. In this work, the LiNi0.5Mn1.5O4 high-voltage material was used to identify this aging mechanism and to investigate its connection to the surface layer formation. Firstly, measurements were carried out on full cells, which had different lithium loadings. By means of the evaluation of the capacity profiles in combination with the method of differential capacity, the dominant aging mechanism could be identified as the loss of free lithium. This lithium is bound in the cell and is no longer available for further cell operation. In order to investigate whether the bound lithium is deposited as a topcoat on the electrode surface, a new method for sample preparation was developed. This results in very smooth sample surfaces and allows an optimal characterization of the surface layers on the battery electrodes. Visual examination of these samples by means of scanning electron microscopy showed the formation of a closed covering layer on the electrode. There are also indications that the surface layer is detached from the electrode surface again as a result of the state of charge. The characterization of the cover layer by means of X-ray photoelectron spectroscopy showed that this consists of decomposition products of the electrolyte and of lithium compounds. Studies on half and full cells showed, that the surface layers on electrodes of ...

In order to achieve the CO$_{2}$ emission targets of the German Government, it is necessary to significantly reduce the CO$_{2}$ emissions of passenger cars. The substitution of the conventional internal combustion engine by a battery electric drive is a suitable method for this purpose. For a high economical use of such vehicles, high range and low cost are of great importance. Both criteria can be achieved by the use of high-voltage cathode materials in the lithium ion batteries used. However, since these materials show a strong aging, their commercial use is not yet possible. The dominant aging mechanism in high-voltage cathode materials is not yet clearly described in the literature. In this work, the LiNi$_{0.5}$Mn$_{1.5}$O$_{4}$ high-voltage material was used to identify this aging mechanism and to investigate its connection to the surface layer formation. Firstly, measurements were carried out on full cells, which had different lithium loadings. By means of the evaluation of the capacity profiles in combination with the method of differential capacity, the dominant aging mechanism could be identified as the loss of free lithium. This lithium is bound in the cell and is no longer available for further cell operation. In order to investigate whether the bound lithium is deposited as a topcoat on the electrode surface, a new method for sample preparation was developed. This results in very smooth sample surfaces and allows an optimal characterization of the surface layers on the battery electrodes. Visual examination of these samples by means of scanning electron microscopy showed the formation of a closed covering layer on the electrode. There are also indications that the surface layer is detached from the electrode surface again as a result of the state of charge. The characterization of the cover layer by means of X-ray photoelectron spectroscopy showed that this consists of decomposition products of the electrolyte and of lithium compounds. Studies on half and full cells showed, that the surface layers ...

The LiCoMnO4 spinel compound was prepared by a sol–gel method. Structural measurements were utilized to investigate the characteristics of LCMO powder. The powder crystallizes in the space group Rd-3m, with a trigonal crystallinity structure, according to XRD analysis (hexagonal axes). SEM images showed that the crystalline grains sizes were about 200 nm - 350 nm, which provides large surface area. The sample had soft magnetic characteristics, according to hysteresis behaviour analysis in the Vibrating Sample Magnetometer (VSM). The prepared material is thought to be a candidate for the applications of energy storage in lithium-ion batteries.

U.S. Ballistic Missile Defense Organization (BMDO) has requirements for pulse power sources of high specific power and specific energy for applications in electric weapons, sensing, and communications systems. These objectives can be met by thin film, high temperature battery components such as a lithium-insertion anode, a lithium intercalation cathode and a high conducting Li(+) ion electrolyte separator. This Phase I program focussed on a new class of Li(+) ion conducting compounds and solid electrolytes made from these compounds using polymer gels. The inorganic Li(+) conductors, which are excellent gel formers, have interesting crystal structures and are thermally and electrochemically stable. The electrolyte separators of 100-200 micrometers thickness, made from these inorganic compounds incorporated in polymeric gels utilizing lithium salts and plasticizer-solvents, have exhibited ionic conductivity of> 5x10(exp -3) S/cm at 100 deg C.

We present the magnetic properties of LiNi1-xCoxPO4 magnetoelectrics, with x = (0-0.2), and their analysis of concentration dependences. Samples have been synthesized by a glycerol-nitrate method. To refine crystal structure X-ray diffraction measurements were carried out. Magnetic measurements were performed at the external magnetic field of 500 Oe over the temperature range (2-300) K. The neutron powder diffraction patterns of LiNi0.9Co0.1PO4 were recorded over temperature interval from 4.4 K up to 25 K. The partial doping in the LiNi1-xCoxPO4 magnetoelectrics the Ni ions for Co ions leads to a narrowing of the temperature interval where the incommensurate phase is established. © Published under licence by IOP Publishing Ltd. ; 3.6121.2017/8.9 ; 02. ; The work was supported by MES of RF (contract No. 3.6121.2017/8.9), and by Act 211 Government of RF (contract No. 02.A03.21.0006).

The increasing demand for portable electronic devices and batteries has led to a growing interest in Li compounds. Lithium manganese oxides (LMO) are the most popular lithium-ion sieves (LIS) precursor materials due to their high lithium adsorption capacity and selectivity. The key step in forming LIS is the lithium desorption process from the crystalline lattice of the LMO. However, this process has been less researched than its counterpart, the lithium adsorption process. In this line, there are some studies describing the process of lithium desorption in acid media from spinel-type LMO. Nevertheless, there is no evidence of the lithium desorption process of layered-type lithium-rich LMO in acidic media. In the present work, we investigated the lithium desorption behavior of different LMO nanocomposites in HCl. LMOs with different Li/Mn ratios were synthesized by promoting the lithium-rich layered phase (Li2MnO3). The morphology, size, crystallinity, chemical composition, and surface properties of LMO nanocomposites and delithiated products were studied. In addition, density functional theory (DFT) calculations were carried out to understand the differential lithium desorption behavior, confirming its dependence on the Li/Mn ratio of the LMO nanocomposites. Herein, we demonstrate that the lithium diffusion energy barrier plays a major role during lithium desorption from LMO nanocomposites. Our results suggest that an exhaustive characterization of lithium precursor materials (LMO) is necessary to select a suitable desorption process ; This work was financially supported by CONICYT PFCHA/ DOCTORADO/2015-21151648 (Ruth Pulido), PFCHA/DOCTORADO/ 2017-21172001 (Nelson Naveas) and partially funded by project USAMPSA, PID-2020-112770-C22, from the Government of Spain. The simulations used in this paper have been performed in the Centro de Computacion ´ Científica-Universidad Autonoma ´ de Madrid (CCC-UAM); thanks to CPU time and other resources granted by the institution