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Lithium primary aqueous

All lithium based batteries use nonaqueous electrolytes because of the reactivity of lithium in aqueous solution and because of the electrolyte s stability at high voltage. The majority of these cells use microporous membranes made of polyolefins. In some cases, nonwovens made of polyolefins are either used alone or with microporous separators. This section will mainly focus on separators used in secondary lithium batteries followed by a brief summary of separators used in lithium primary batteries. [Pg.184]

Lithium primary cells have typical energy densities of up to 250 Wh/kg (500 Wh/dm3), which are twice as high as the best conventional aqueous... [Pg.108]

Lithium primary batteries are a comparatively new type of primary battery. Since they were first introduced, however, they have found a variety of applications, mainly in consumer uses. Lithium batteries have the lightweight properties of lithium, such as low specific gravity (0.53) and low potential (-3.0 V vs NHE), and by using a non-aqueous electrolyte solution, they have the following superior characteristics ... [Pg.150]

Lithium batteries use nonaqueous solvents for the electrolyte because of the reactivity of lithium in aqueous solutions. Organic solvents such as acetonitrile, propylene carbonate, and dimethoxyethane and inorganic solvents such as thionyl chloride are typically employed. A compatible solute is added to provide the necessary electrolyte conductivity. (Solid-state and molten-salt electrolytes are also used in some other primary and reserve lithium cells see Chaps. 15, 20, and 21.) Many different materials were considered for the active cathode material sulfur dioxide, manganese dioxide, iron disulfide, and carbon monofluoride are now in common use. The term lithium battery, therefore, applies to many different types of chemistries, each using lithium as the anode but differing in cathode material, electrolyte, and chemistry as well as in design and other physical and mechanical features. [Pg.328]

The reactivity of lithium in aqueous solutions requires the use of nonaqueous electrolytes for lithium anode batteries. Polar organic hquids are the most common electrolyte solvents for the active primary cells, except for the thionyl ehloride (SOCy and sulfuryl chloride (SO2CI2) cells, where these inorganie compounds serve as both the solvent and the active cathode material. The important properties of the eleetrolyte are ... [Pg.332]

Among all of the metal-air couples, the lithium-oxygen (Li-02) couple is especially attractive because it has the highest theoretical specific energy, as was shown in Table 22.1. Primary aqueous lithium-air batteries have been used for decades in applications such as life-vest beacons the battery is activated by sea water, and the... [Pg.773]

In the first method a secondary acetylenic bromide is warmed in THF with an equivalent amount of copper(I) cyanide. We found that a small amount of anhydrous lithium bromide is necessary to effect solubilization of the copper cyanide. Primary acetylenic bromides, RCECCH Br, under these conditions afford mainly the acetylenic nitriles, RCsCCHjCsN (see Chapter VIII). The aqueous procedure for the allenic nitriles is more attractive, in our opinion, because only a catalytic amount of copper cyanide is required the reaction of the acetylenic bromide with the KClV.CuCN complex is faster than the reaction with KCN. Excellent yields of allenic nitriles can be obtained if the potassium cyanide is added at a moderate rate during the reaction. Excess of KCN has to be avoided, as it causes resinifi-cation of the allenic nitrile. In the case of propargyl bromide 1,1-substitution may also occur, but the propargyl cyanide immediately isomerizes under the influence of the potassium cyanide. [Pg.155]

Payne rearrangement. The Payne rearrangement2 of a primary cts-2,3-epoxy alcohol to a secondary 1,2-epoxy alcohol usually requires a basic aqueous medium, but it can be effected with BuLi in THF, particularly when catalyzed by lithium salts. As a consequence, the rearrangement becomes a useful extension of the Sharpless epoxidation, with both epoxides available for nucleophilic substitutions. Thus the more reactive rearranged epoxide can be trapped in situ by various organometallic nucleophiles. Cuprates of the type RCu(CN)Li are particularly effective for this purpose, and provide syn-diols (3).3... [Pg.63]

Initial development of ambient secondary lithium batteries was based on the primary lithium systems described in Chapter 4, consisting of a lithium metal negative, a non-aqueous lithium ion conducting electrolyte and a positive electrode material which could undergo a reversible electrochemical reaction with lithium ions ... [Pg.198]

Lithium aluminum hydride is a convenient reagent for reduction of nitro compounds, nitriles, amides, azides, and oximes to primary amines. Catalytic hydrogenation works also. Aromatic nitro compounds are reduced best by reaction of a metal and aqueous acid or with ammonium or sodium polysulfides (see Section 23-12B). Reduction of /V-substituted amides leads to secondary amines. [Pg.1607]

Cancer pagurus cuticle can be dispersed in hot, aqueous solutions of lithium thiocyanate and be reprecipitated without separating the chitin and protein components. The stability of the complex under these conditions would suggest the presence of primary bonding. Thus, some ehitin-protein bonding does exist in arthropod cuticle, but its exact nature and its physiological significance or its involvement in chitin biosynthesis (or both) remain uncertain. [Pg.375]

Increased hydrolytic stability of the ester function is readily attained by shielding the carbonyl group from nucleophilic attack. Thus, pivalates are slow to deprotect compared with acetates and the protracted reaction times required for cleavage of the pivalate may be incompatible with other protecting groups such as the TBS ethers. In such instances, the pivalate may be cleaved in good yield by reduction with diisobutylalaneJ576 604 In a synthesis of Laurencin, a secondary acetate was selectively cleaved in the presence of a primary pivalate with lithium hydroxide in aqueous methanol [Scheme 4.337).640 Subsequent deprotection of the pivalate in the presence of the TBS ether was then effected with diisobutylalane. [Pg.337]


See other pages where Lithium primary aqueous is mentioned: [Pg.566]    [Pg.91]    [Pg.566]    [Pg.66]    [Pg.150]    [Pg.436]    [Pg.186]    [Pg.148]    [Pg.465]    [Pg.1011]    [Pg.487]    [Pg.147]    [Pg.442]    [Pg.251]    [Pg.297]    [Pg.330]    [Pg.96]    [Pg.353]    [Pg.287]    [Pg.223]    [Pg.333]    [Pg.16]    [Pg.441]    [Pg.107]    [Pg.243]    [Pg.363]    [Pg.350]    [Pg.414]    [Pg.41]    [Pg.679]    [Pg.205]    [Pg.288]    [Pg.281]    [Pg.281]    [Pg.146]    [Pg.169]    [Pg.129]   
See also in sourсe #XX -- [ Pg.773 ]




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