Carbon bases lithium

Kinoshita, K., X. Song, J. Kim, and M. Inaba. 1999. Development of a carbon-based lithium microbattery. J Power Sources 81-82 170-175. 

Quantitative Analysis of All llithium Initiator Solutions. Solutions of alkyUithium compounds frequentiy show turbidity associated with the formation of lithium alkoxides by oxidation reactions or lithium hydroxide by reaction with moisture. Although these species contribute to the total basicity of the solution as determined by simple acid titration, they do not react with allyhc and henzylic chlorides or ethylene dibromide rapidly in ether solvents. This difference is the basis for the double titration method of determining the amount of active carbon-bound lithium reagent in a given sample (55,56). Thus the amount of carbon-bound lithium is calculated from the difference between the total amount of base determined by acid titration and the amount of base remaining after the solution reacts with either benzyl chloride, allyl chloride, or ethylene dibromide. 

The double titration method, which involves the use of ben2ylchloride, 1,2-dibromoethane, or aUyl bromide, determines carbon-bound lithium indirectly (101,102). One sample of the //-butyUithium is hydroly2ed directly, and the resulting alkalinity is determined. A second sample is treated with ben2ylchloride and is then hydroly2ed and titrated with acid. The second value (free base) is subtracted from the first (total base) to give a measure of the actual carbon-bound lithium present (active base). 

The United States produces and consumes about one-half of all the wodd production. Ore grades for the two principal nonbrine producers are becoming poor, and imports of brine-based lithium carbonate are increa sing. 

The structure and composition of the lithium surface layers in carbonate-based electrolytes have been studied extensively by many investigators [19-37], High reactivity of propylene carbonate (PC) to the bare lithium metal is expected, since its reduction on an ideal polarizable electrode takes place at much more positive potentials compared with THF and 2Me-THF [18]. Thevenin and Muller [29] found that the surface layer in LiC104/PC electrolyte is a mixture of solid Li2C03 and a... 

State-of-the-art thin film Li" cells comprise carbon-based anodes (non-graphitic or graphite), solid polymer electrolytes (such as those formed by solvent-free membranes, for example, polyethylene oxide, PEO, and a lithium salt like LiPFe or LiCFsSOs), and metal oxide based cathodes, in particular mixed or doped oxides... 

Currently, graphite-based lithium ion batteries use mixed solvent electrolytes containing highly viscous ethylene carbonate (EC) and low viscosity dilutants such as dimethyl carbonate (DMC) or diethyl carbonate (DEC) as main solvents. EC is indispensable because of its excellent filming characteristics. DMC and/or DEC are required to get the low temperature... 

Said subjects are being analyzed in this work. Also, the authors have attempted to show that in order to be suitable for lithium-ion applications, a carbon-based active material has to meet a complex number of physicochemical and electrochemical characteristics. A simple check of galvanostatic behavior, which is often used today to conclude about carbon s suitability for lithium-ion battery technology, is rarely enough for making an accurate assessment. 

Carbonaceous materials with varying degree of graphitic order are the most common commercial anodes in secondary lithium-ion batteries. Among carbon-based materials, natural graphite is the most promising anode... 

Propylene-ammonia reaction, 10 135 Propylene-based routes, to methyl methacrylate, 16 251-252 Propylene carbonate, in lithium cells, 3 459... 

Probably the most common fluxes are sodium carbonate (Na2C03), lithium tetraborate (Li2B407), and lithium metaborate (LiB02). Fluxes maybe used by themselves or in combination with other compounds, such as oxidizing agents (nitrates, chlorates, and peroxides). Applications include silicates and silica-based samples and metal oxides. 

Figure 60. Discharge capacities of LiNiCo02/MCMB lithium ion cells at -20 °C with different carbonate-based electrolytes. Cells are charged at room temperature and discharged using a C/15 rate. (Reproduced with permission from ref 515 (Figure 4). Copyright 2003 Elsevier.)...

Metallation of 3,4-dimethyl-l,2,5-thiadiazole (55) to the anion (56) was accomplished with the use of a nonnucleophilic base, lithium diisopropylamide <82JHC1247>. Nucleophilic attack at sulfur resulted in an alkyllithium reagent <70CJC2006>. The lithiomethyl derivative (56) was carboxylated to (57) with carbon dioxide and converted to the vinyl derivative (58) via an esterification, reduction, mesylation, and base elimination sequence (Scheme 12). 

Figure 1. Enthalpies of interaction of THF ( ) and 2 J-dimethyltetrahydrofuran (0) with 0.03M solutions of polystyryllithium in benzene at 25°C R - [base]/[Li] where [Li] is the concentration of carbon-bound lithium atoms in the solution.

In addition to carbon-based systems, other intercalation compounds are also currently being proposed as alternative lithium ion cell negative plates. Examples include LiJtTiS2, Li/TiC, L /H-sO and, more recently, a family of Li SnOv compounds. However, the applicability of these materials in practical batteries has not yet been established, and coke and graphite are still the materials used in all commercial lithium ion cells. 

Quantitative Analysis of Alkyllithium initiator Solutions. The amount of carbon-bound lithium is calculated from the difference between the tolal amount of base determined by acid titration and the amount of base remaining after the solution reacts with either benzyl chloride, ally I chloride, or ethylene dibromide. 

The base used may be hydroxide, alkoxide, carbonate, alkyl lithium, or alumina (13, 20, 24, 41, 49). The reaction is the reverse of the vinylidene synthesis by protonation of the n-acetylide, and the two complexes form a simple acid-base system. For the iron complexes in Eq. (2), the pK has been measured at 7.78 (in 2 1 thf-H20) (24). 

A solid-state solar cell was assembled with an ionic liquid—l-ethyl-3-methylimidazolium bis(trifluoromethanesulfone)amide (EMITFSA) containing 0.2 M lithium bis(trifluoromethanesulfone)amide and 0.2 M 4-tert-butylpyridine—as the electrolyte and Au or Pt sputtered film as the cathode.51,52 The in situ PEP of polypyrrole and PEDOT allows efficient hole transport between the ruthenium dye and the hole conducting polymer, which was facilitated by the improved electronic interaction of the HOMO of the ruthenium dye and the conduction band of the hole transport material. The best photovoltaic result ( 7p=0.62 %, 7SC=104 pA/cm2, FOC=0.716 V, and FF=0.78) was obtained from the ruthenium dye 5 with polypyrrole as the hole transport layer and the carbon-based counterelectrode under 10 mW/cm2 illumination. The use of carbon-based materials has improved the electric connectivity between the hole transport layer and the electrode.51... 

The topic of this book is focused on active masses containing carbon, either as an active mass (e.g., negative mass of lithium-ion battery or electrical double layer capacitors), as an electronically conducting additive, or as an electronically conductive support for catalysts. In some cases, carbon can also be used as a current collector (e.g., Leclanche cell). This chapter presents the basic electrochemical characterization methods, as applicable to carbon-based active materials used in energy storage and laboratory scale devices. 

The first commercial lithium-ion cell containing a carbon based hybrid material is the Sony Nexelion cell which was introduced in 2006.30 Nexelion cells contain a graphite/cobalt-doped amorphous tin hybrid electrode. Batteries of this cell type are used in video cameras which require high energy density but can accept the lower cycling stability of the Nexelion batteries compared to conventional lithium-ion battery systems. 

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