Structures and Formation Energies of Li_xC_6 (x=1-3) and its Homologues for Lithium Rechargeable Batteries

• Published in: Bulletin of the Korean Chemical Society pp. 2045 - 2050
• Main Authors: 도칠훈, 한병찬, 진봉수, Hal-Bon Gu
• Format: Journal Article
• Language: English
• Published: 대한화학회 01.06.2011
• Subjects: 화학
• ISSN: 0253-2964; 1229-5949

Using first principles density functional theory the formation energies of various binary compounds of lithium graphite and its homologues were calculated. Lithium and graphite react to form Li_1C_6 (+141 mV) but not form LiC_4 (.143 mV), LiC_3 (.247 mV) and LiC_2 (.529 mV) because they are less stable than lithium metal itself. Properties of structure and reaction potentials of C_5B, C_5N and B_3N_3 materials as iso-structural graphite were studied. Boron and nitrogen substituted graphite and boron-nitrogen material as a iso-electronic structured graphitic material have longer graphene layer spacing than that of graphite. The layer spacing of Li_xC_6, Li_xC_5B,Li_xC_5N materials increased until to x=1, and then decreased until to x=2 and 3. Nevertheless Li_xB_3N_3 has opposite tendency of layer spacing variation. Among various lithium compositions of Li_xC_5B, Li_xC_5N and Li_xB_3N_3, reaction potentials of Li_xC_5B (x=1-3) and Li_xC_5 (x=1) from total energy analyses have positive values against lithium deposition. KCI Citation Count: 16