Lithium iodine

Fig. 24. Cutaway view of lithium—iodine pacemaker ceU in case-grounded, central anode configuration (36).

Leclanche or dry cell Alkaline Cell Silver-Zinc Reuben Cell Zinc-Air Fuel Cell Lithium Iodine Lithium-Sulfur Dioxide Lithium-Thionyl Chloride Lithium-Manganese Dioxide Lithium-Carbon Monofluoride... 

Lithium hydroxide, 15 134, 140-141 Lithium hypochlorite, 4 52 15 141 pool sanitizer, 26 175 Lithium iodide, 3 417 15 140 Lithium-iodine cells, 3 463-464 characteristics, 3 462t speciality for military and medical use, 3 430t... 

Li2S204 being the SEI component at the Li anode and the solid discharge product at the carbon cathode. The Li—SOCI2 and Li—SO2 systems have excellent operational characteristics in a temperature range from —40 to 60 °C (SOCI2) or 80 °C (SO2). Typical applications are military, security, transponder, and car electronics. Primary lithium cells have also various medical uses. The lithium—silver—vanadium oxide system finds application in heart defibrillators. The lithium—iodine system with a lithium iodide solid electrolyte is the preferred pacemaker cell. 

Likewise, aryllithiums generated by lithium-iodine exchange undergo intramolecular cyclization to give pyrrolo-azepine 72. The best results were obtained when Weinreb (R = Me, = OMe) or morpholine amides were used as internal electrophiles, resulting in 66 and 70% yields, respectively (Equation (7) (2005T331D). 

Lithium-iodine cells are produced simply by making direct contact between anode and cathode. On touching, a thin layer of lithium iodide is formed by direct reaction. As soon as the layer becomes complete, the reaction rate decreases sharply, since diffusiou of iodine through lithium iodide is very slow. Thus the cell may be written as... 

Fig. 9.9 Lithium-iodine solid state button cell for electric watches and pocket calculators. (By courtesy of Catalyst Research Corporation.)...

Fig. 9.11 Projected discharge characteristics of a nominal 400 mAh lithium-iodine solid state cell. (By permission of Catalyst Research Corporation.)...

The high reliability and the complete absence of faults such as electrolyte leakage or gas generation make the lithium-iodine solid state battery a particularly suitable device for powering implanted electronic devices, and it is now widely used in the cardiac pacemaker industry. The design and construction of Medtronic Inc, pacemaker batteries are shown in Fig. 9.12. A typical unit, such as the Enertec Alpha 33 , has dimensions of 33.4 mm X 27.4 mm X 7.9 mm, giving a total volume of 6.0 cm3 and a mass of 22 g. The cell has a completely welded construction and uses a specialized... 

Fig, 9,12 Cutaway of a lithium-iodine pacemaker cell. (By courtesy of Medtronic Inc.)... 

Schlosser and co-workers have reported the shift of lithium in lithiated l-bromo-3-(tri-fluoromethyl)benzene 2,fa Quenching at — 100 C gives exclusively the product derived from 2, whereas after 2 hours at — 75 C, arene 2 is completely converted into less basic 3. A lithium-iodine exchange takes place in lithiated 2-chloro-3-iodo-6-(trifluoromethyl)pyridine 4, which at —85 C is totally converted into the less basic isomer 5.7 These rearrangements have been discussed in terms of a base-catalyzed halogen dance or halogen-shuffling mechanism. 

Solid Cathode Cells. Solid cathode cells include lithium-manganese dioxide cells, lithium carbon inonofluoridc cells, lithium iron disulfide cells, and lithium—iodine cells. 

Bailey, W. F. Brubaker, J. D. Jordan, K. P. Effect of solvent and temperature on the lithium-iodine exchange of primary alkyl iodides reaction of tBuLi with 1-iodooctane in heptane-ether mixtures./. Organomet. Chem. 

The lithium/iodine-poly-(2-vinyl pyridine) system has some unique properties. Its major application is in implantable medical devices such as cardiac pacemakers, which operate at a thermostatted 37°C [28], The reaction is... 

Iodine — Iodine, L, is a halogen which occurs naturally mainly as iodide, I- [i]. Iodine (Greek ioeides for colored violet ) is a black solid with a melting point of 113.6 °C which is readily undergoing sublimation to form a violet gas. Iodine occurs in the oxidation states -1,0, +1, +3, +5, +7 and it possesses a rich redox chemistry [ii]. In aqueous solution the formation of I2 from I- occurs with a standard potential of 0.621V vs. SHE and this oxidation process is preceded by the formation of I3 with a standard potential of 0.536 V vs. SHE. For the reaction I2(cryst) + 2e - 21 E = 0.535 V. The I—/I3 redox couple is employed, for example, in solar cells [iii] and in long-lived lithium-iodine battery systems. The oxidation of I2 in organic solvents results formally in I+ intermediates which is a powerful oxidant and useful, for example, in electro-synthetic chemical processes [ii]. 

Selenophene-3-aldehyde has been obtained by the Sommelet reaction of 3-bromomethylselenophene (obtained from 3-methyl-selenophene and A-bromosuccinimide), by reaction of dimethyl-formamide with 3-lithioselenophene (obtained by lithium-iodine exchange at — 60°C),74 and by reduction and subsequent hydrolysis of selenophene-3-carbonitrile.75... 

Intramolecular conjugate additions of unsaturated esters. Reaction of the ester la with n-butyllithium at — 100° results in r-butyl cyclopentylacetate (2a) in 82% yield. The cyclization presumably involves a rapid lithium-iodine exchange to form a nucleophilic center that undergoes an intramolecular conjugate addition to form a cy-... 

The lithium-iodine solid-state battery is used exclusively for heart pacemaker. The electrode reactions in this case are very simple, leading to the overall cell reaction ... 

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