Chemical and electrochemical intercalation of lithium into boronated carbons

Boron-substituted carbons have been produced by chemical vapour deposition from acetylene and boron trichloride precursors at 1140 degrees C. Li inter calation was investigated, chemically from the Li vapour and electrochemica lly in Li-carbon cells. In both cases, the amount of intercalated Li increa ses with the boron content of the carbon, up to a value of 13 at.% boron. A bove this value, the intercalation of lithium is not so efficient. This beh aviour is understood by assuming that boron, which acts as an electron acce ptor and hence favours the intercalation of electron donors like lithium, c an enter substitutionally into the carbon lattice up to a certain limit, wh ich is close to 13 at.% for the materials deposited at 1140 degrees C. (C) 1999 Elsevier Science Ltd. All rights reserved.