Lithium-chloride cells

Measurement of conductivity of a fibre. If a fibre is impregnated with an electrolyte, such as lithium chloride, its electrical resistance will be governed by its moisture content, which in turn depends on the humidity of the atmosphere in which it is situated, Iri a lithium chloride cell, a skein of very fine fibres is wound on a plastic frame carrying the electrodes and the current flowing at a constant applied voltage gives a direct measure of the relative humidity. 

Lithium—Thionyl Chloride Cells. Lidiium—thionyi chloride cells have very high energy density. One of the main reasons is the nature of the ceU reaction. 

The geometry of ionic crystals, in which there are two different kinds of ions, is more difficult to describe than that of metals. However, in many cases the packing can be visualized in terms of the unit cells described above. Lithium chloride, LiCl, is a case in point Here, the larger Cl- ions form a face-centered cubic lattice (Figure 9.18). The smaller Li+ ions fit into holes between the Cl- ions. This puts a Li+ ion at the center of each edge of the cube. 

Sulfur dioxide is soluble in the electrolyte. Sulfur is soluble up to about 1 mol dm 3, but it precipitates in the cathode pores near the end of discharge. Lithium chloride is essentially insoluble and precipitates on the surfaces of the pores of the carbon cathode, forming an insulating layer which terminates the operation of cathode-limited cells [37],... 

An experimental investigation of explosion hazards in lithium-sulfinyl chloride cells on forced discharge showed cathode limited cells are safe, but anode limited cells may explode without warning signs [1]. Extended reversal at -40°C caused explosion on warming to ambient temperature, owing to thermal runaway caused by accelerated corrosion of lithium [2], The violent explosion of a large prismatic cell of a battery is described [3], Another study of explosion mechanisms in lithium/thionyl chloride batteries is reported [4]... 

Consider the Daniell cell Zn Zn2+ Cu2+ Cu. The cell emf is about 1.1 V when prepared with clean, pure electrodes and both solutions at unit activity. The emf decreases to about 1.05 V after adding lithium chloride to the copper half-cell. Adding more LiCl, but this time to the zinc solution, increases the emf slightly, to about 1.08 V. 

Lithium sulfuryl chloride batteries, 23 654 Lithium SVO cells, speciality for military and medical use, 3 430t Lithium t-butoxide, 15 148 Lithium tetraborate, 15 137 Lithium tetrafluoroborate, in lithium cells, 3 459... 

Lithium tetrahydridothallate(III), 24 632 Lithium tetrahydroborate, physical properties of, 4 194t Lithium—thionyl chloride cells, 3 466 characteristics, 3 462t speciality for military and medical use, 3 430t... 

The materials used in nonwoven fabrics include a single polyolefin, or a combination of polyolefins, such as polyethylene (PE), polypropylene (PP), polyamide (PA), poly(tetrafluoroethylene) (PTFE), polyvinylidine fluoride (PVdF), and poly(vinyl chloride) (PVC). Nonwoven fabrics have not, however, been able to compete with microporous films in lithium-ion cells. This is most probably because of the inadequate pore structure and difficulty in making thin (<25 /rm) nonwoven fabrics with acceptable physical properties. 

Alkynes can be reduced electrolytically. Internal alkynes gave 65-80% yields of cis alkenes when electrolysed in 10% sulfuric acid in ethanol at spongy nickel cathode [127], or predominantly trans alkenes if the electrolysis was carried out in a methylamine solution of lithium chloride. The yields of the alkenes and the ratios of trans to cis alkenes varied depending on whether the electrolysis was carried out in divided or undivided cells (yields 24-80%, composition of product 89-99% of trans alkene) [379]. 

V-Acylsaccharins prepared by treatment of the sodium salt of saccharin with acyl chlorides were reduced by 0.5 molar amounts of sodium bis(2-methoxyethoxy)aluminum hydride in benzene at 0-5° to give 63-80% yields of aliphatic, aromatic and unsaturated aldehydes [1108 Fair yields (45-58%) of some aliphatic aldehydes were obtained by electrolytic reduction of tertiary and even secondary amides in undivided cells fitted with platinum electrodes and filled with solutions of lithium chloride in methylamine. However, many secondary and especially primary amides gave 51-97% yields of alcohols under the same conditions [130]. 

In an electrolytic cell (Fig. 5) consisting of platinum electrodes (2 cm x 5 cm in area) and cathode and anode compartments separated by an asbestos divider, each compartment is charged with 17 g (0.4 mol) of lithium chloride and 450 ml of anhydrous methylamine. Isopropylbenzene (12 g, 0.1 mol) is placed in the cathode compartment and a total of 50,000 coulombs (2.0 A, 90 V) is passed through the solution in 7 hours. After evaporation of the solvent the mixture is hydrolyzed by the slow addition of water and extracted with ether the ether extracts are dried and evaporated to give 9.0 g (75%) of product boiling at 149-153° and consisting of 89% of a mixture of isomeric isopropylcyclohexenes and 11% of recovered isopropylbenzene. 

Lithium chloride is used in the production of lithium metal by electrolysis. It also is used in metallurgy as a eutectic melting composition with potassium chloride (LiCl 41 mol% KCl 59 mol%). Other applications are in low temperature dry-cell batteries as a dehumidifier in air conditioning in welding and soldering flux as a desiccant in fireworks and in mineral waters and soft drinks. 

Lithium has numerous pharmacologic effects. It is able to cross through sodium channels, competing with monovalent and divalent cations in cell membranes (AHFS, 2000). Animal studies have shown that lithium at a serum level of 0.66 + — 0.08 mEq/L can increase the amphetamine-induced release of serotonin (5-hydroxytryptamine [5-HT]) and the concentrations of a serotonin metabolite (e.g., 5-hydroxyindoleacetic acid [5-HIAA]) in the perifornical hypothalamus (PFH) of rats before and after chronic lithium chloride administration (Baptista et ah, 1990), a mechanism possibly involved in lithium s antidepressant effect. The precise neurobiological mechanisms through which lithium reduces acute mania and protects against recurrence of illness remain uncertain (Lenox and Hahn,... 

The cell reaction thus leads to the formation of relatively insoluble lithium chloride at the cathode, which under some circumstances may block the porous carbon current collector, leading to an increased internal resistance. Another product is S02, which may lead to an increasing internal pressure as the discharge continues. However, in practice most of the S02 remains dissolved and the pressure build-up is small. Further electrochemical reduction of S02 to form lithium dithionite may also occur. A number of other possible reactions have been suggested, and as... 

Fig. 4.35 Discharge curves of D-size lithium-thionyl chloride cells at ambient temperature (a) 3.0 A (b) 1.0 A (c) 0.1 A...

Lithium-thionyl chloride cells are also constructed as reserve batteries... 

The energy density of liquid cathode lithium cells can be further enhanced to over 500 Wh/kg (1000 Wh/dm3) by the use of halogen additives. BrCl, added to lithium-thionyl chloride cells, boosts the OCV to 3.9 V and prevents the formation of sulphur in the early stages of discharge. D-sized cells are manufactured, Addition of chlorine to lithium-sulphur yl chloride cells increases the energy density and improves the temperature-dependent electrical characteristics. 

Liquid Cathode Cells. Liquid cathode cells include lithium-sulfur dioxide cells and lithium-thionyl chloride cells. 

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