Tight-binding quantum chemical molecular dynamics study of cathode materials for lithium secondary battery

摘要

Our tight-binding quantum chemical molecular dynamics (TBMD) program was applied to the investigation of the structural and electronic properties of LixMn2O4. The calculated lattice constants of the LiMnO4 and lambda-MnO2 were 8.17 and 8.08 Angstrom, respectively, which are in good agreement with experimental results. The electronic analysis showed that the manganese atoms n the LiMn2O4 were separated into two groups based on their electronic states, which correspond to Mn3+ and Mn4+. We calculated the average potential for the reaction of Li + Mn2O4 --> LiMn2O4 and obtained the average potential of 4.2 V. The experimental value of the potential is approximately 4.0 V, indicating that our program is a powerful tool to predict the potential of various materials, as well as their atomistic and electronic structures. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 23]