Lithium cobalt dioxide

Lithium cobalt dioxide, uses, 7 24 It Lithium complex greases, 15 243 Lithium compounds, 20 598-599. See also Organolithium compounds inorganic, 15 136-142 uses for, 15 134 Lithium cyanide, 8 194 Lithium 5—alumina, 2 406t... 

Auborn, J.J., and Barberio, Y.L. 1987. Lithium intercalation cells without metallic lithium. Molybdenum dioxide/lithium cobalt dioxide and tungsten dioxide/lithium cobalt dioxide. Journal of the Electrochemical Society 134, 638-647. 

One of the oldest forms (and is a very common form) of rechargeable and wet type is the lead-acid battery. Alternative chemical reactions have given way to new rechargeable battery cells like lithium ion and metal hydride. Typical lithium ion anodes are based on carbon while the cathode is made from lithium cobalt dioxide, lithium manganese dioxide, or many other chemical combinations. 

The energy density of commercial cells has almost doubled since their introduction in 1991 since 1999 the volumetric energy density has increased from 250 to over 400 Wh/1. Details of the original commercial cells have been reviewed by Nishi, where key aspects are discussed concerning the need for large particle size, 15—20 /increase safety and the intentional incorporation of lithium carbonate into the cathode to provide a safety valve. The lithium carbonate decomposes, releasing carbon dioxide when the charging exceeds 4.8 V, which breaks electrical flow in the cell. These lithium cobalt oxides also contain excess lithium and can be best represented by the formula... 

The following procedure is based on the reaction of an aqueous solution of cobalt(II) chloride with the equivalent amount of (2-aminoethyl)carbamic acid, followed by oxidation with hydrogen peroxide and the subsequent formation of bis(ethylene-diamine)cobalt(III) ions. The bis(ethylenediamine)cobalt(lII) species are converted to the carbonato complex by reaction with lithium hydroxide and carbon dioxide. During the entire preparation a vigorous stream of carbon dioxide is bubbled through the reaction mixture. This procedure appears to be essential in order to minimize the formation of tris(ethylenediamine)cobalt(III) chloride as a by-product. However, the formation of a negligible amount of the tris salt cannot be avoided. The crude salts have a purity suitable for preparative purposes. The pure salts are obtained by recrystallization from aqueous solution. 

The procedure described here is based on the observation that amine monohydroxo complexes of cobalt(III), rhodium(IIl), and iridium(III) react directly with carbon dioxide to form the corresponding carbonato complexes,2 3 without effect on the configuration of the amine ligands.4 The amine monoaqua complex is allowed to react with lithium carbonate or carbon dioxide gas at room temperature at pH 8.0 for a few minutes, and the carbonato complex is isolated by adding alcohol. The procedure has been used to prepare salts of the following cations pentaammine(carbonato)-cobalt(III),2 ds-ammine(carbonato)bis(ethylenediamine)cobalt(III),5 trans-... 

One can see that decomposition temperatures of these compounds are within temperature range 40-600°C. Some compounds, such as monohydrate of lithium hydroxide (40°C), hydrated titanium dioxide (60°C), iron hydroxide (100°C), manganese (145°C) and cobalt (150°C) hydroxides, tungsten acid (180°C), etc., start to release water at relatively low temperatures. Other compounds decompose at a temperature above 200°C. No correlation between formation enthalpy and thermal stability of hydroxides and hydrated oxides is observed. 

The ruthenium-cobalt bimetallic complex system catalyzes the homologation of methanol with carbon dioxide and hydrogen in the presence of iodide salts. A synergistic effect is found between these two metals. The yield of ethanol is also affected by the Lewis acidity of the iodide salt, lithium iodide being most effective. The reaction profile shows that methanol is homologated with CO formed by the hydrogenation of CO2. 

---