@article{924b5cd5a8a14d0780ce855c6f4d6d72,
title = "Structure and properties of deeply Li-doped Polyacenic Semiconductor (PAS)",
abstract = "As an anode material of lithium rechargeable battery, amorphous carbon materials have been studied extensively because of their high electrochemical performance. The polyacenic semiconductor (PAS) materials prepared from phenol resin at relatively low temperatures (500-1000 °C) show a highly Li-doped state up to C2Li state without liberation of Li cluster. The Li storage mechanism as well as the large hysteresis observed in the voltage-capacity profile of the amorphous carbon materials are still the subjects of controversy. We review the proposed models of Li storage mechanism and present the results of our molecular orbital (MO) calculations. It will be shown that the nature of Li dopant is strongly dependent on the position of Li dopant. Possibility of the formation of small Li clusters is also discussed.",
author = "Tokio Yamabe and Kazuyoshi Tanaka and Hiroki Ago and Kazunari Yoshizawa and Shizukuni Yata",
note = "Funding Information: The Li storage mechanism of hydrogen-containing carbons (carbon treated at low temperatures) are reviewed with respect to recent proposed models. Understanding of the Li storage mechanism as well as the electronic structure is a significant and interesting subject for further development of. the rechargeable battery. On the other hand, from a number of experiments such as 7Li NMR, ESR, and Raman measurements, Li-doping mechanism has been gradually understood. As a clue to the Li storage mechanism, we have investigated the geometric and electronic structures of Li-doped carbon materials on the basis of semiempirical MO analyses. Intercalant Li which is almost completely ionized is stabilized well by both the negatively-charged upper and lower carbon layers, which results at most in the formation of the C6Li configuration. On the other hand, adsorbing Li atoms on the carbon layer can form small Li cation clusters concomitant with fully ionized Li atoms. Very small Li clusters are allowed to exist only on the carbon layer surface because of the restriction of the Li-Li distance of such clusters. Acknowledgments - This work was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan and by JSPS Program for Supporting University-Industry Cooperative Research Project.",
year = "1997",
month = feb,
day = "28",
doi = "10.1016/s0379-6779(97)81181-2",
language = "English",
volume = "86",
pages = "2411--2414",
journal = "Synthetic Metals",
issn = "0379-6779",
publisher = "Elsevier BV",
number = "1-3",
}