Lithium-carbon batteries

Table 13. Specifications of secondary lithium-carbon batteries...

TM oxide insertion 293-321 lithium carbon batteries, secondary 45 lithium carbon materials 361... 

In the literature of recent years, we indeed see more and more publications on the study and development of novel nonaqueous high energy density battery systems, nonaqueous electro-organic synthesis, and mechanistic studies. This parallels worldwide efforts to commercialize nonaqueous lithium and lithium-carbon batteries. Hence, it is important to gather from time to time the knowledge accumulated in these areas, to update the literature and provide the increasing number of people working in this field with a comprehensive compendium on the practical and theoretical aspects of nonaqueous electrochemistry. 

Another matter, of relevance to activation of carbons, was the observation that whereas cesium, mbidium and potassium could easily form intercalation compounds, sodium and lithium were quite unreactive, but not totally so. Further, sodium apparently prefers to intercalate into less-ordered carbons (not graphitic) and lithium has its own characteristics when it comes to insertion into carbon (electrically driven) for the lithium-carbon battery. 

Lithium Carbon Batteries. These batteries are made in an hermetically sealed stainless-steel container with a metallic lithium anode, a Ketjen black carbon cathode, and a LiAlCl4 6SO2 electrolyte. The cathode composition is 96% Ketjen black and 4% Teflon. Teflon-rich carbon-coated nickel exmet is used as the cathode substrate. These batteries are made cathode-limited with the anode capaeity at least twiee the cathode capacity. Batteries are vacuum filled with the electrolyte. The open-eireuit voltage of the system is about 3.3 V. The average discharge voltage is 3.1 V at 1 mA/em. It is heheved that high-surface-area carbon forms a complex with the electrolyte, and this eomplex takes part in the cell reaction. 

Lithium Bromide. Lithium biomide [7550-35-8] LiBi, is piepaied from hydiobiomic acid and lithium carbonate oi lithium hydroxide. The anhydrous salt melts at 550°C and bods at 1310°C. Lithium bromide is a component of the low melting eutectic electrolytes ia high temperature lithium batteries. 

Lithium Iodide. Lithium iodide [10377-51 -2/, Lil, is the most difficult lithium halide to prepare and has few appHcations. Aqueous solutions of the salt can be prepared by carehil neutralization of hydroiodic acid with lithium carbonate or lithium hydroxide. Concentration of the aqueous solution leads successively to the trihydrate [7790-22-9] dihydrate [17023-25-5] and monohydrate [17023-24 ] which melt congmendy at 75, 79, and 130°C, respectively. The anhydrous salt can be obtained by carehil removal of water under vacuum, but because of the strong tendency to oxidize and eliminate iodine which occurs on heating the salt ia air, it is often prepared from reactions of lithium metal or lithium hydride with iodine ia organic solvents. The salt is extremely soluble ia water (62.6 wt % at 25°C) (59) and the solutions have extremely low vapor pressures (60). Lithium iodide is used as an electrolyte ia selected lithium battery appHcations, where it is formed in situ from reaction of lithium metal with iodine. It can also be a component of low melting molten salts and as a catalyst ia aldol condensations. 

L2 Why is carbon a suitable candidate for the anode of a Lithium-ion Battery ... 

One criterion for the anode material is that the chemical potential of lithium in the anode host should be close to that of lithium metal. Carbonaceous materials are therefore good candidates for replacing metallic lithium because of their low cost, low potential versus lithium, and wonderful cycling performance. Practical cells with LiCoOj and carbon electrodes are now commercially available. Finding the best carbon for the anode material in the lithium-ion battery remains an active research topic. 

The work presented in this chapter involves the study of high capacity carbonaceous materials as anodes for lithium-ion battery applications. There are hundreds and thousands of carbonaceous materials commercially available. Lithium can be inserted reversibly within most of these carbons. In order to prepare high capacity carbons for hthium-ion batteries, one has to understand the physics and chemistry of this insertion. Good understanding will ultimately lead to carbonaceous materials with higher capacity and better performance. 

Carbons deseribed in sections 3 and 5 have already been used in practical lithium-ion batteries. We review and briefly describe these earbon materials in seetion 6 and make a few coneluding remarks. 

Graphitic carbon is now used as the anode material in lithium-ion batteries produced by Moli Energy (1990) Ltd., Matsushita, Sanyo and A+T battery. It is important to understand how the structures and properties of graphitic carbons affect the intercalation of lithium within them. 

In lithium-ion battery applications, it is important to reduce the cost of electrode materials as much as possible. In this section, we will discuss hard carbons with high capacity for lithium, prepared from phenolic resins. It is also our goal, to collect further evidence supporting the model in Fig. 24. 

Chapter 11 reports the use of carbon materials in the fast growing consumer eleetronies applieation of lithium-ion batteries. The principles of operation of a lithium-ion battery and the mechanism of Li insertion are reviewed. The influence of the structure of carbon materials on anode performance is described. An extensive study of the behavior of various carbons as anodes in Li-ion batteries is reported. Carbons used in commereial Li-ion batteries are briefly reviewed. 

Table S, Specifications of coin-type lithium-carbon monofluoride batteries...

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