Intercalation compounds, electrically conducting

Further improvements in anode performance have been achieved through the inclusion of certain metal salts in the electrolyte, and more recently by dkect incorporation into the anode (92,96,97). Good anode performance has been shown to depend on the formation of carbon—fluorine intercalation compounds at the electrode surface (98). These intercalation compounds resist further oxidation by fluorine to form (CF ), have good electrical conductivity, and are wet by the electrolyte. The presence of certain metals enhance the formation of the intercalation compounds. Lithium, aluminum, or nickel fluoride appear to be the best salts for this purpose (92,98). 

Elastic-inelastic collision model, Szilard-Chalmers reaction and, 1 269 Electrical conduction, in organic superconductors, 29 278-286 Electrical conductivity of chalcogenide halide compounds, 23 331 of Group IB, 23 337-339, 342, 346-349 photoelectric effects, 23 368, 410 semiconductors, 23 368, 390, 395-396, 400-402, 410-412 superconductors, 23 375-377 of graphite intercalation compounds, 23 290, 294, 309-310, 312, 317-318 Electric discharges arc type, 6 146-147 chemical reactions in, 6 189-191 chemical reactions in, 6 143-206... 

The potassium donates an electron to the graphite (forming and the conductivity of the graphite increases. Graphite electron-acceptor intercalation compounds have also been made with NO3T CrOs, Br2, FeCls, and ASF5. Some of these compounds have electrical conductivity approaching that of aluminum (see Chapter 6). 

Titanium disulfide has a Cdl2 structure (see Chapter 1). The solid is golden-yellow and has a high electrical conductivity along the titanium layers. Forming intercalation compounds with electron donors can increase the conductivity of titanium disulfide, the best example being with lithium, LLTiS2. This compound is synthesized in the cathode... 

In lithium polymer batteries, one electrode is lithium foil, or in some cases another electrically conducting material such as graphite, and the other is a reversible intercalation compound as in liquid electrolyte lithium batteries. Compounds used as intercalation electrodes include LiCo02 and VeOis. The cell developed in the Anglo-Danish project, which ran from 1979 to 1995, was... 

Both of the potassium and polybromide intercalation compounds are good conductors of electricity. In the potassium inlercalam. the electrons in the conduction band can carry the current directly, as in a metal. In the compounds of graphite with polybromide. holes in the valence band conduct by the mechanism discussed previously for semiconductors (Chapter 7). 

Pietronero, L. and S. Strassler. 1981. Bond length, bond strength and electrical conductivity in carbon based systems. In L. Pietronero, E. Tossati (eds.), Physics of Intercalation Compounds pp. 23-32. Springer-Verlag, Berlin. 

As charges are injected in the chains, electrical neutrality is maintained by counterion insertion in the polymer matrix. In this way conducting polymers resemble intercalation compounds, with the difference that usually the counterions arrange randomly. In some cases, however (more especially in poly acetylene, but also in poly aniline), ordering of the counterions, or stages, has been observed. The ion insertion can thus be compatible with a crystalline structure. It has been observed, however, that the crystallinity is degradated on cycling (see Chapter 12, Section II.C). 

Graphite intercalation compounds have received widespread interest for two main reasons. First, intercalation results in compounds that have metallic conductivity. The electrical conductivity can approach that of copper metal and is highly anisotropic ratios of the conductivity in-plane to that along the c axis can be six orders of magiutude at room temperature. Secondly, graphite is a unique host lattice in that intercalation compounds can be formed with either electron donors or electron acceptors as guest species. 

T. E. Thompson, E. M. McCarron and N. Bartlett, The Electrical Conductivity of Graphite-AsFs Intercalation Compounds and Their Relationship to Other Graphite-MFe Salts, Synthetic Metals 3 (1981) 255-267. 

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