7439-93-2Relevant articles and documents
Effect of electrolyte composition on lithium dendrite growth
Crowther, Owen,West, Alan C.
, p. A806-A811 (2008)
Lithium deposition is observed in situ using a microfluidic test cell. The microfluidic device rapidly sets up a steady concentration gradient and minimizes ohmic potential loss, minimizes electrolyte usage, and shows good repeatability. Dendrite growth is observed at different current densities for electrolytes containing lithium hexafluorophosphate or lithium bis(trifluoromethane sulfonyl) imide (LiTFSI) in mixtures of propylene carbonate (PC) and dimethyl carbonate. Dendrites are formed at shorter times in electrolytes containing LiTFSI and high amounts of PC. The time to first observed dendrites increases linearly (for all electrolyte compositions) with a resistance given by the Tafel slope of the lithium reduction polarization curve.
Electrochemical formation of Sm-Ni alloy films in a molten LiCl-KCl-SmCl3 system
Iida, Takahisa,Nohira, Toshiyuki,Ito, Yasuhiko
, p. 2537 - 2544 (2001)
The electrochemical formation of Sm-Ni alloys was investigated in a molten LiCl-KCl-SmCl3 (0.5 mol%) system at 723 K. The cyclic voltammogram for a Mo electrode showed the reduction wave from Sm(III) to Sm(II) at 1.60 V (vs Li+/Li), but no reduction wave from Sm(II) to Sm metal. For a Ni electrode, small cathodic currents were observed at potentials more negative than 0.10 V, which indicated the formation of Sm-Ni alloy. The formation of an SmNi2 phase was confirmed by XRD analysis of a sample prepared at 0.10 V for 72 h. The thickness of the SmNi2 film was estimated to be approximately 100 nm. A much thicker SmNi2 film (~20 μm) was obtained by cathodic galvanostatic electrolysis at 50 mA cm-2 in a time period as short as 1 h. Since Li metal was codepositing during the electrolysis and the SmNi2 film was rapidly formed, this electrochemical formation method was termed the 'Li codeposition method'. The formed SmNi2 film was changed to other alloy phases by anodic potentiostatic electrolysis. The formation potentials of SmNi5, SmNi3 and SmNi2 were found to be 1.20, 0.65 and 0.29 V, respectively.
Delayed release of Li atoms from laser ablated lithium niobate
Chaos,Dreyfus,Perea,Serna,Gonzalo,Afonso
, p. 649 - 651 (2000)
The present vapor-phase optical (atomic) absorption measurements study the escape dynamics of Li atoms from a LiNbO3 target surface upon laser ablation in vacuum. The objective is to understand the low-Li content of LiNbO3 films prepared by pulsed laser deposition. A primary result is a delayed release of Li atoms, 2-20 μs after the laser pulse; they eject with a velocity of 6 × 105 cms-1, which is consistent with an electronic ejection mechanism. The long emission period means there are almost no intraplume Li collisions in the gas phase and no forward focusing of the delayed released atoms. This appears to explain the low-Li content usually found in films grown in the normal direction.
Ormont, B.,Petrow, B. A.
, (1936)
Effects of some organic additives on lithium deposition in propylene carbonate
Mogi, Ryo,Inaba, Minoru,Jeong, Soon-Ki,Iriyama, Yasutoshi,Abe, Takeshi,Ogumi, Zempachi
, p. A1578-A1583 (2002)
The effects of some film-forming organic additives, fluoroethylene carbonate (FEC), vinylene carbonate (VC), and ethylene sulfite (ES), on lithium deposition and dissolution were investigated in 1 M LiClO4 dissolved in propylene carbonate (PC) as a base solution. When 5 wt % FEC was added, the cycling efficiency was improved. On the contrary, addition of 5 wt% VC or ES significantly lowered the cycling efficiency. The surface morphology of lithium deposited in each electrolyte solution was observed by in situ atomic force microscopy (AFM). In PC + FEC, the surface was covered with a uniform and closely packed layer of particle-like deposits of about 100-150 nm diam. The surface film seemed to be more solid in PC + VC, and inhomogeneous in PC + ES. From ac impedance measurements, it was revealed that the surface film formed in PC + FEC has a lower resistance than that in the additive-free solution, whereas that formed in PC + VC or PC + ES has a higher resistance. Large volume changes during lithium deposition and dissolution require that the surface film should be elastic (or soft) and be self-repairable when being damaged. In addition, a nonuniform current distribution is liable to cause dendrite formation, which requires that the surface film should be uniform and its resistance should be as low as possible. PC + FEC gave a surface film that satisfies all these requirements, and therefore only FEC was effective as an additive for deposition and dissolution of lithium metal.
Kahlenberg, L.
, p. 602 - 603 (1899)
Mueller et al.
, p. 419 (1922)
Quantum properties of nanoscale metallic Li colloids formed by electron irradiation in LiF
Beuneu,Vajda
, p. 329 - 333 (2003)
We present experimental results on the nucleation of nanoscale metallic lithium colloids, of well-controlled diameter (2-5 nm), in MeV electron-irradiated LiF single crystals. Conduction electron spin resonance experiments show a clear-cut quantum effect in these colloids: the spin susceptibility follows a mixed Curie-Pauli law, characteristic for tiny metallic particles in which the mean level spacing is comparable to kT. The behavior of the spin relaxation times (T1 and T2) is presented and a discussion of quantum size effect in small metallic particles is proposed.
Marchac, T.,Bukovec, P.,Bukovec, N.
, p. 305 - 310 (1988)
ELECTROCHEMICAL BEHAVIOUR OF Co3O4 AND CoO CATHODES IN HIGH-TEMPERATURE CELLS.
Thackeray,Baker,Coetzer
, p. 405 - 411 (1982)
Preliminary investigations of the electrochemical behavior of Li-Al/LiCl, KCl/Co//3O//4 and Li-Al/LiCl, KCl/CoO cells are reported. At an operating temperature of 420 degree C, maximum discharge capacities of up to 546 mA-h per gram of cobalt oxide were r
Surface film formation and lithium underpotential deposition on Au(111) surfaces in propylene carbonate. In situ scanning tunneling microscopy study
Saito, Toshiya,Uosaki, Kohei
, p. A532-A537 (2003)
The formation and the morphological change of surface film on a Au(111) electrode in propylene carbonate solution containing 0.1 M LiClO4 in the potential region between 0.8 and 2.5 V (Li/Li+) were studied by in situ scanning tunneling microscopy. The surface film was observed on a gold electrode at potentials more negative than 1.5 V (Li/Li+), and many nuclei appeared on the flat terrace of the electrode at potentials more negative than 0.9 V, where underpotential deposition of lithium on gold was started. Many holes on the surface film were observed after the dissolution of lithium and were thought to be formed as a result of breakdown of the film in nanometer order. The deposition and dissolution of the submonolayer lithium affected the surface morphology in nanometer order.
Structural and functional analysis of surface film on li anode in vinylene carbonate-containing electrolyte
Ota, Hitoshi,Sakata, Yuuichi,Otake, Yumiko,Shima, Kunihisa,Ue, Makoto,Yamaki, Jun-Ichi
, p. A1778-A1788 (2004)
The lithium cycling efficiencies of the lithium anode in the ethylene carbonate (EC)-based electrolytes were improved by adding vinylene carbonate (VC) to the electrolyte. We analyzed the surface films of deposited lithium on a nickel substrate in a VC-containing electrolyte with scanning electron microscopy, Fourier transform infrared spectroscopy, two-dimensional nuclear magnetic resonance, gel permeation chromatography, and X-ray photoelectron spectroscopy. The corresponding surface films comprise various polymeric species including poly-(vinylene carbonate) [poly-(VC)], oligomeric VC, and a ring-opened polymer of VC. Furthermore, the surface film of carbon double bonds (C = C-O) and lithium carboxylate (RCOOLi) as reduction products of VC were formed on deposited lithium. These structures of the surface film on the lithium anode were similar to those on the graphite anode. At elevated temperatures, the VC-containing electrolyte led to the formation of surface films comprising poly(VC). The VC-derived polymeric surface film, which exhibited gel-like morphology, could prevent the deleterious reaction which occurs between deposited lithium and the electrolyte, resulting in an enhanced lithium cycling efficiency. 2004 The Electrochemical Society.
Hydrogen production via thermochemical water-splitting by lithium redox reaction
Nakamura, Naoya,Miyaoka, Hiroki,Ichikawa, Takayuki,Kojima, Yoshitsugu
, p. S410-S413 (2013/11/19)
Hydrogen production via thermochemical water-splitting by lithium redox reactions was investigated as energy conversion technique. The reaction system consists of three reactions, which are hydrogen generation by the reaction of lithium and lithium hydrox