Lithium perchlorate-1,2-dimethoxyethane

Lithium iodide, 57, 37 Lithium, methyl, 55, 7, 10,58, 43 Lithium perchlorate- 1,2-dimethoxyethane complex, 57, 74... 

Anhydrous lithium perchlorate (60 g.) obtained from Ventron Corporation was placed in a 500-ml. flask under dry nitrogen, and 85 ml. of anhydrous 1,2-dimethoxyethane was added. The mixture became... 

When the lithium perchlorate was dissolved initially in the entire 240 ml. of 1,2-dimethoxyethane and processed as above, the yield was considerably lower. The submitters report that, if less lithium perchlorate is used in the preparation of the octamethyltetraoxaquaterene, the yield of the product is lowered. 

Lithium perchlorate, complex with 1,2-dimethoxyethane, 57, 74 Lithium, phenyl-, [591-51-5], 55, 11 58, 138... 

There is as yet no consolidated opinion as to the optimum electrolyte for lithium-sulfiir batteries. Experiments with solid polymer electrolyte are described, but aprotic electrolyte in a Celgard-type separator commonly used in lithium ion batteries is applied more frequently. A large number of electrolytes has been studied that differ both in solvents and the lithium salt. The greatest acceptance was gained by lithium imide solutions in dioxolane (or in a mixture of dioxolane and dimethoxyethane) and also lithium perchlorate solutions in sulfone. Dissolution of polysulfides in electrolyfe is accompanied by a noticeable increase in viscosity and specific resistance of electrolyte. It is the great complexity of the composition of the electrochemical system and that of the processes occurring therein that prevent as yet commercialization of lithium-sulfiir electrolytes. 

Barthel J, Neueder R, Poepke H, Wittmann H (1999) Osmotic coefficients and activity coefficients of nonaqueous electrolyte solutions. Part 2. Lithium perchlorate in the aprotic solvents acetone, acetonitrile, dimethoxyethane, and dimethylcarbonate. J Solution Chem 28 489-503... 

Some workers have tried to correlate the Raman spectra of lithium perchlorate solutions with macroscopic (conductance and viscosity) measurements [229,230,237,238]. In 1,2-dimethoxyethane and 2-methoxyethanol, Raman spectroscopy shows that the solvation of the lithium ion is accomplished through the ethereal oxygen atom in both solvents and there is a good qualitative correlation between the degree of ionic pairing demonstrated by the conductance measurements and that revealed by the Vi(A,) envelope of the perchlorate anion. 

In Li-Mn02 batteries, lithium perchlorate (LiCl04) or lithium trifluoromethane-sulfonate (LiCp3S03) is widely employed as an electrolytic solute, and mainly propylene carbonate (PC) and 1,2-dimethoxyethane (DME) are employed as a mixed solvent. The PC-DME-UCLO4 electrolyte shows high conductivity (>10 cm ) and low viscosity (<3 cP). 

A disadvantage of the vanadium pentoxide cathode is its relatively low electronic conductivity. To offset this the cell is modified with 10% w/w carbon powder and 5% PTFE binder. The anode is pure lithium. The electrolyte consists of 1m lithium perchlorate dissolved in propylene carbonate or 1 1 propylene carbonate 1 2 dimethoxyethane. 

Some details on the construction of this type of cell are shown in Figure 24.16. The current collector is a sheet of perforated stainless steel. The stainless steel top cap functions as the negative terminal and the stainless steel cell can as the positive terminal of the cell. The polypropylene closure is highly impermeable to water vapour and prevents moisture entering the cell after it has been sealed. The separator is of non-woven polypropylene cloth and contains the electrolyte, a solution of lithium perchlorate in a mixture of propylene carbonate and dimethoxyethane. The lithium negative electrode is punched from sheet lithium and the manganese dioxide cathode is made from a highly active electrolytic oxide. 

Two companies (Eveready and venture Technology) have been involved in the development of these cells. The venture Technology AAA type bobbin cell introduced in 1982 has a stainless steel can with lithium foil in contact with the inner surface. The positive electrode is a composite of iron disulphide (FCS2), graphite and PTFE binder on an aluminium grid. The separator is porous polypropylene and the electrolyte a solution of lithium perchlorate in a 1 1 v/v propylene carbonate 1 2 dimethoxyethane mixture. 

Created electrolyte comprised of solvent and ionic species. Possible ionic species include lithium tetrafluoroborate, tetrabutylammonium perchlorate, and tetraethylammonium tetrafluoroborate. Salt most preferred is ethyltriethylammonium tetrafluoroborate preferred solvent is non-aqueous. Examples include ethylene carbonate, propylene carbonate, N-methypyrrolidione, 1,2-dimethoxyethane, methyl formate, sulfuryl chloride, and tributyl phosphate. The most preferable solvent is a nitrile, specifically propionitrile. AIM solution of MTEATFB in propionitrile yielded conductivity of 48 mS/cm at 95°C and 28 mS/cm at 23°C. 

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