Lithium intercalation-deintercalation

Different investigations of the mechanisms of capacity degradation during cycling show that one of the main reasons of this degradation is significant change (by a factor of 3-4) in AM volume on the intercalation-deintercalation of lithium, followed by AM destruction [2-3],... 

The benefit of a hybrid phase for the intercalation-deintercalation of mobile species such as Li+ cations is well illustrated by the study of conductive polymers such as polyaniline or polypyrrole intercalated into a V2O5 framework as potential electrode materials in lithium batteries [34]. For PANI/V2O5, an oxidative post-treatment performed under an oxygen atmosphere allowed the authors to compare the conductivity attributed to the polymer, as in absence of reduced cations, there was no electronic hopping between ions, and the conductive state was due only to the... 

The metastable spinel form of TiS2, which has cubic close-packing of the sulfide ions, was similarly formed by the deintercalation of copper from CuTi2S4. ° This cubic structure can also be reversibly intercalated with lithium, although the diffusion coefficient is not as high as in the layered form. 

Figure 16. Voltage profiles for the first two lithium intercalation/deintercalation cycles realized on graphite anode in t-BC/EMC and c-BC/EMC solutions of 1.0 M LiPEe. (Reproduced with permission from ref 255 (Eigure 7). Copyright 2000 The Electrochemical Society.)...

Finally, NMR has also be used to study other spinels materials that do not contain manganese. For example, the intercalation/deintercalation of lithium titanate spinels such as Li4/3+Ji5/304 and Lii.i-Tii.904+a have been investigated. These materials may be used as anode materials in combination with cathodes operating at 4 V (vs Li) to produce cells with potentials of ca. 2.5 V. These materials are either diamagnetic or metallic, and unlike the mangan-ates, only very small differences in shifts are seen for Li in the different sites of the spinel structure. Nonetheless, these shift differences are enough to allow the concentrations of the different sites to be quantified and monitored following insertion of Li or as a function sample preparation method. ... 

As discussed in the next section, lithiated carbon electrodes are covered with surface films that influence and, in some cases, determine their electrochemical behavior (in terms of stability and reversibility). They are formed during the first intercalation process of the pristine materials, and their formation involves an irreversible consumption of charge that depends on the surface area of the carbons. This irreversible loss of capacity during the first intercalation/deintercalation cycle is common to all carbonaceous materials. However, several hard, disordered carbons exhibit additional irreversibility during the first cycle, in addition to that related to surface reactions with solution species and film formation. This additional irreversibility relates to consumption of lithium at sites of the disordered carbon, from which it cannot be electrochemically removed [346-351],... 

Figure 23.2 Galvanostatic intercalation-deintercalation of lithium in graphite using a two-electrode lithium-graphite cell. The inset is a magnification of the curve at low potential, which shows the existence of different stage domains. The potential plateaus during reduction represent the successive transitions from stages III to II and to I.

When cationic guest atoms such as lithium, hydrogen, and sodium reversibly enter or leave the host oxide crystal, along with an accompanying electron flow but without any change in crystal structure, the reaction is referred to as intercalation/ deintercalation as follows [1, 2] ... 

In this respect, this chapter details the fundamentals and most important advances in the research activities on lithium intercalation into and deintercalation from transition metals oxides and carbonaceous materials, especially from thermodynamic and kinetic points of view, including methodological overviews. The thermodynamics of lithium intercalation/deintercalation is first introduced with respect to a lattice gas model with various approximations, after which the kinetics of lithium intercalation/deintercalation are described in terms of a cell-impedance-controlled model. Finally, some experimental methods which have been widely used to explore the thermodynamics and kinetics of lithium intercalation/deintercalation are briefly overviewed. 

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