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Structural Elucidation of tert-Butyllithium/Lithium Alkoxide and Lithium Hydride/Lithium Alkoxide Mixed Aggregates

Description: The effects of lithium alkoxides on the rates of reactions and on the structures of a series of tert-butyllithium/lithium alkoxide mixed aggregates were studied, where the alkoxides were iso-butoxide, tert-butoxide and menthoxide. It was found that their effects depend not only on their amount present, but also on their steric bulk. The tert-butyllithium/lithium alkoxide mixed aggregates were exposed to UV light or heat to form lithium hydride/lithium alkoxide mixed aggregates. The aggregation states were assigned from either 13C-6Li coupling or a new technique based on the relative intensity of NMR peaks using different nuclei. The compounds formed depend upon the method of formation and the alkoxide. The unique properties of the lithium hydride/lithium alkoxide mixed aggregates are their high solubility in hydrocarbon solutions, very reactive bases, showing 6Li-1H couplings, and having only one hydride ion per aggregate. Their formation, reactivity, solubility, and aggregation states were found to depend on the size of lithium alkoxides. X-ray crystal structures of lithium tert-butoxide and lithium menthoxide were also studied and found to be hexameric.
Date: December 1997
Creator: Nguyen, Hanh D.
Partner: UNT Libraries

Engineering Development of Lithium/Metal Sulfide Battery Technology for Vehicle Propulsion : Summary Report, October 1977- September 1978

Description: The research, development, and management activities done in preparation for in-vehicle testing of engineering-scale lithium/metal sulfide batteries are described. These activities were carried out at Argonne National Laboratory (ANL) from October 1977 to September 1978. Over the past year, lead--acid batteries were tested both in the laboratory and in a Renault automobile. The data obtained from these tests will be used to assess the performance of lithium/metal sulfide batteries. Testing of a 40 kWh lithium/metal sulfide battery in a vehicle is planned for early 1979. The equipment needed to evaluate the performance of this battery was designed and fabricated. Testing of this equipment is expected to begin at the end of 1978. In order to carry out the above in-vehicle test, the lithium/metal sulfide battery must have a thermally efficient case and a charger. Construction of such a case is in progress. A portable charger/equalizer that has the capability of charging up to six lithium/metal sulfide cells was fabricated.
Date: March 1979
Creator: Barney, Duane L.; Chilenskas, A. A.; DeLuca, W. H.; Hayes, E. R.; Hornstra, F.; Farahat, M. K. et al.
Partner: UNT Libraries Government Documents Department

Determination of Hydrogen in Lithium Hydride

Description: Abstract: "A method for determining hydrogen in lithium hydride by heating samples with lead at 600 C, was developed. The hydrogen evolved during thermal decomposition of the hydride is purified and oxidized to water with cupric oxide at 400 C. The analysis is completed by collecting and weighing this water. Success in development of the analytical procedure has depended upon a careful design and assembly of equipment for handling samples in a dry, inert atmosphere. For seven pure hydride samples analyzed by the recommended method the estimates of the standard deviation varied between 0.12 and 0.41 percent lithium hydride (or 1.3 and 4.2 parts per thousand) for 8 to 18 determinations on each sample. The procedure is relatively insensitive to variations in certain conditions. For single-piece samples weighing 0.2 to 0.5 gram it was found to be more satisfactory than a method which uses mercury in place of lead for sample decomposition. For powdered lithium hydride samples the lead and mercury methods are equally satisfactory."
Date: May 1954
Creator: Bergstresser, K. S. & Waterbury, Glenn R.
Partner: UNT Libraries Government Documents Department

Fast Neutron Interactions with Li⁶ and Li⁷

Description: Abstract: "Measurements have been made of the cross sections for the reactions Id-6(n, dn)He-4 and Li-7(n, tn)He-4 over an incident neutron energy range of 5 - 14 MeV. The energy and angular distributions of all reaction products were determined."
Date: July 18, 1963
Creator: Rosen, Louis, {}
Partner: UNT Libraries Government Documents Department

Li⁶ and Li⁷ (n. 2n) Cross Sections at 14.1 Mev

Description: Abstract: "An absolute measurement of the 14.1-Mev (n, 2n) cross sections of Li-6 and Li-7 has been made using the large scintillator technique, resulting in cross sections in barns of 0.070 +/- 0.006 and 0.056 +/- 0.005 for Li-6 and Li-7, respectively."
Date: May 29, 1958
Creator: Ashby, V. J.; Catron, H. C.; Newkirk, Lester L.; Taylor, C. J. & Williamson, M. A.
Partner: UNT Libraries Government Documents Department

An NMR Study of 2-Ethylbutyllithium/Lithium 2-Ethyl-1-butoxide Mixed Aggregates, Lithium Hydride/Lithium 2-Ethyl-1-butoxide Mixed Aggregates, n-Pentyllithium Aggregates, and n-Pentyllithium/Lithium n-Pentoxide Mixed Aggregates

Description: A 13C and 6Li variable temperature NMR study of 2-ethylbutyllithium/lithium 2-ethyl-1-butoxide mixed aggregates formed from reacting 2-ethyl-1-butanol with 2-ethylbutyllithium in two O/Li ratios of 0.2/1 and 0.8/1. The 0.2/1 sample resulted in two 2-ethylbutyllithium/lithium 2-ethyl-1-butoxide mixed aggregates and seven lithium hydride/lithium 2-ethyl-1-butoxide mixed aggregates. The lithium hydride mixed aggregates were also studied using selective 1H decoupling experiments. The 0.8/1 sample resulted in six 2-ethylbutyllithium/lithium 2-ethyl-1-butoxide mixed aggregates and five lithium hydride/lithium 2-ethyl-1-butoxide mixed aggregates. A low temperature 13C NMR spectroscopy study of n-pentyllithium indicated three aggregates, most likely a hexamer, an octamer, and a nonamer. A low temperature 13C NMR study of an 0.2/1 O/Li ratio sample of n-pentyllithium mixed with 1-pentanol resulted in three n-pentyllithium/lithium n-pentoxide aggregates mixed aggregates along with the three n-pentyllithium aggregates. 13C NMR data for this mixture gave inconclusive results whether or not lithium hydride/lithium alkoxide mixed aggregates were present in the sample.
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Date: December 2005
Creator: Sellers, Nicole
Partner: UNT Libraries

Lithium-oxide-stabilized alpha manganese dioxide for rechargeable lithium batteries

Description: Objective was to increase the reversible cycling capacity of anhydrous {alpha}-MnO{sub 2} by stabilizing its structure. We have synthesized various {alpha}-MnO{sub 2} materials and modified their structures via lithia doping in order to determine what properties are important for controlling cycling performance. A set of new stabilized {alpha}-[xLi{sub 2}O]{center_dot}MnO{sub 2} (x<0.2) cathode materials was synthesized, structurally characterized, and electrochemically evaluated.
Date: June 1996
Creator: Johnson, C. S.; Dees, D. W.; Mansuetto, M. F.; Thackeray, M. M.; Vissers, D. R.; Argyriou, D. et al.
Partner: UNT Libraries Government Documents Department

Electron-Population Analysis and the Dipole Moment of the LiH ¹Σ⁺ Excited State / A.M. Karo

Description: Abstract: "Detailed consideration is given to some properties of the first excited electronic state. Following the analysis proposed bv Mulliken, SCF LCAO-MO coefficients are used to obtain qualitative information about the electron distributions. Comparison is made with earlier work with respect to the description of the excited-state dipole moment, the effective electric moment between the ground and excited states is also calculated. From this, the oscillator strength for the first allowed transition is computed as a function of the internuclear distance."
Date: July 1959
Creator: Karo, Arnold M.
Partner: UNT Libraries Government Documents Department

Magnetic Diagnostics for the Lithium Tokamak eXperiment

Description: The Lithium Tokamak eXperiment (LTX) is a spherical tokamak with R0 = 0.4m, a = 0.26m, BTF ∼ 3.4kG, IP ∼ 400kA, and pulse length ∼ 0.25s. The focus of LTX is to investigate the novel, low-recycling Lithium Wall operating regime for magnetically confined plasmas. This regime is reached by placing an in-vessel shell conformal to the plasma last closed flux surface. The shell is heated and then coated with liquid lithium. An extensive array of magnetic diagnostics is available to characterize the experiment, including 80 Mirnov coils (single and double-axis, internal and external to the shell), 34 flux loops, 3 Rogowskii coils, and a diamagnetic loop. Diagnostics are specifically located to account for the presence of a secondary conducting surface and engineered to withstand both high temperatures and incidental contact with liquid lithium. The diagnostic set is therefore fabricated from robust materials with heat and lithium resistance and is designed for electrical isolation from the shell and to provide the data required for highly constrained equilibrium reconstructions.
Date: June 20, 2008
Creator: L. Berzak, R. Kaita, T. Kozub, R. Majeski, and L. Zakharov
Partner: UNT Libraries Government Documents Department

Lithium-endohedral C{sub 60} complexes.

Description: High capacity, reversible, lithium intercalated carbon anodes have been prepared, 855 m.Ah/g, which exceed the capacity for stage 1 lithium intercalated carbon anodes, 372 mAh/g. Since there is very little hydrogen content in the high capacity anode, the fullerene C{sub 60} lattice is used to investigate the nature of lithium ion bonding and spacing between lithiums in endohedral lithium complexes of C{sub 60}. Three lithium-endohedral complexes have been investigated using ab initio molecular orbital calculations involving 2,3 and 5 lithium. The calculated results suggest that lithium cluster formation may be important for achieving the high capacity lithium carbon anodes.
Date: May 4, 1998
Creator: Scanlon, L. G.
Partner: UNT Libraries Government Documents Department

Plasma Synthesis of Lithium Based Intercalation Powders for Solid Polymer Electrolyte Batteries

Description: The invention relates to a process for preparing lithium intercalation compounds by plasma reaction comprising the steps of: forming a feed solution by mixing lithium nitrate or lithium hydroxide or lithium oxide and the required metal nitrate or metal hydroxide or metal oxide and between 10-50% alcohol by weight; mixing the feed solution with O2 gas wherein the O2 gas atomizes the feed solution into fine reactant droplets, inserting the atomized feed solution into a plasma reactor to form an intercalation powder; and if desired, heating the resulting powder to form a very pure single phase product.
Date: January 4, 2005
Creator: Kong, Peter C.; Pink, Robert J. & Nelson, Lee O.
Partner: UNT Libraries Government Documents Department

Electronic Properties of LiFePO4 and Li doped LiFePO4

Description: LiFePO{sub 4} has several potential advantages in comparison to the transition metal oxide cathode materials used in commercial lithium-ion batteries. However, its low intrinsic electronic conductivity ({approx} 10{sup -9} S/cm) is problematic. We report here a study by soft x-ray absorption/emission spectroscopy of the electronic properties of undoped LiFePO{sub 4} and Li-doped LiFePO{sub 4} in which Li{sup +} ions are substituted for Fe{sup 2+} ions in an attempt to increase the intrinsic electronic conductivity. The conductivities of the Li{sub 1+x}Fe{sub 1-x}PO{sub 4} samples were, however, essentially unchanged from that of the undoped LiFePO{sub 4}. Nonetheless, evidence for changing the electronic properties of LiFePO{sub 4} by doping with excess Li+ was observed by the XAS/XES spectroscopy. New pre-edge features the O-1s XAS spectrum of Li{sub 1.05}Fe{sub 0.95}PO4 is a direct indication that the charge compensation for substitution of Fe{sup 2+} by Li{sup +} resides in the unoccupied O-2p orbitals. A charge transfer (CT) excitation was also observed in the doped material implying that the unoccupied O-2p orbitals created by doping are strongly hybridized with unoccupied Fe-3d orbitals of neighboring sites. However, the strong covalent bonding within the (PO{sub 4}){sup 3-} anions and the large separation of the Fe cations means that the charge created by doping is not delocalized in the manner of electrons or holes in a semiconductor.
Date: May 31, 2006
Creator: Allen, J.L.; Zhuang, G.V.; Ross, P.N.; Guo, J.-H. & Jow, T.R.
Partner: UNT Libraries Government Documents Department

Li+ alumino-silicate ion source development for the Neutralized Drift Compression Experiment (NDCX)

Description: We report results on lithium alumino-silicate ion source development in preparation for warmdense-matter heating experiments on the new Neutralized Drift Compression Experiment (NDCXII). The practical limit to the current density for a lithium alumino-silicate source is determined by the maximum operating temperature that the ion source can withstand before running into problems of heat transfer, melting of the alumino-silicate material, and emission lifetime. Using small prototype emitters, at a temperature of ~;;1275 oC, a space-charge-limited Li+ beam current density of J ~;;1 mA/cm2 was obtained. The lifetime of the ion source was ~;;50 hours while pulsing at a rate of 0.033 Hz with a pulse duration of 5-6 mu s.
Date: October 1, 2010
Creator: Roy, Prabir K.; Greenway, Wayne G.; Kwan, Joe W.; Seidl, Peter A.; Waldron, William L. & Wu, James K.
Partner: UNT Libraries Government Documents Department