Intercalation of lithium

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. 

Heman L, Morales J, Sanchez L, Tirado JL (1993) Kinetics of intercalation of Lithium and Sodium into (PbS)i,i4(NbS2)2. Chem Mater 5 1167-1173... 

Naji A., Willmann P., and Billaud D. Electrochemical Intercalation of Lithium into Graphite Influence of the Solvent Composition and the Nature of the Lithium Salt. Carbon, 36, 1347-1352 (1998). 

The specific capacity obtained in such Ams, actually corresponds to near theoretical limit of 372 mA-h/g, as calculated on a basis of classical LiC6 stoichiometry). Further increase of capacity is possible only via switching to new or modified materials, composites or alloys, which are capable for reversible and stable intercalation of lithium. 

In recent years lithium - ion power sources have occupied one of the first places among other modem energy storage systems. Their functioning is based on the possibility of reversible intercalation of lithium ions in active materials (AM). Substances of tin are investigated often as negative materials for lithium-ion batteries. 

Being thermally decomposed onto the surface of carbon, this complex is expected to form very small catalytically active NiCo204 spinel centers. Thus, we have studied the catalytic activity of the products of pyrolysis at different temperatures toward two electrochemical reactions -reduction of oxygen in alkaline electrolyte and intercalation of lithium into carbons in aprotic electrolyte of Li-ion battery. To our knowledge, the catalytic effect of the metal complexes in the second reaction was not yet considered in the literature. 

Abe, T., Kawabata, N., Mizutani, Y., Inaba, M., and Ogumi, Z., Correlation between cointercalation of solvents and electrochemical intercalation of lithium into graphite in propylene carbonate solution, J. Electrochem. Soc. (2003) 150 (3), A257-A261. 

Guerard D., Herold A. Intercalation of lithium into graphite and other carbons. Carbon 1975 13 337-45. 

Intercalation of species into the CNT structure has also been performed. For instance, the intercalation of lithium in CNTs [93,94] is one attractive topic due to the potential applications in electrochemical energy storage in lithium batteries. Edge-plane defects turn out to be very important for such processes [95]. 

Figure 25. (top) Electrochemical intercalation of lithium into e-V0P04, ° and (bottom) relationship between the various structures in the VOPO4 system the building block for all these structures is shown at the lower right. 

Magnetic susceptibility and Li and magnetic resonance results of FePSj and their lithium intercalates reveal that iron remains in the high-spin divalent state. In Li NiPSj, electrons added by intercalation of lithium seem to go to the transition-metal 4s or higher empty sulphur orbitals. The disappearance of magnetism in Li NiPSj for x > 0.5 is not understood. 

The electrochemical discharge-charge process of the battery is based on the intercalation/de-intercalation of lithium molybdenum disulphide ... 

Figure 26. Displacement of the layer stacking sequence (see text) on intercalation of lithium in graphite.11 Reprinted from J. Maier, Physical Chemistry of Ionic Materials. Ions and Electrons in Solids. Copyright 2004 with permission from John Wiley Sons, Ltd.

They showed that the reversible charge capacity of heat-treated cokes as a function of their degree of graphitization is in remarkable agreement with the expression (Equation 7.6) if xaa = 0.75, xaP = 0.20, and Xpp = 1. The lower value of xap was qualitatively confirmed by STM observations on pyrocarbons heat-treated at 2000°C.172 In the ap state, interstitial clusters of carbon atoms which commensurate with the graphite lattice hindered the intercalation of lithium and, thus, decreased the stoichiometric coefficient x with respect to a random distribution of interstitials. 

Winter M, Besenhard JO. Electrochemical intercalation of lithium ion batteries. In Wakihara M, Yamamoto O (Eds.), Lithium Ion Batteries Fundamentals and Performance. Wiley-VCH, New York, 1998 127. 

Maurin G, Bousquet Ch, Henn F, Bernier P, Almairac R, Simon B. Electrochemical intercalation of lithium into multiwall carbon nanotubes. Chem Phys Lett 1999 312 14-18. 

Intercalation electrodes may include either carbon electrodes or transition metal oxide and sulfide electrodes, which intercalate with solution components such as metal cations. The most important example is intercalation of lithium ions with many types of carbonaceous materials at low potentials (0-1.5 V versus Li/Li+)... 

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