Work

Vibrational Contribution to the Thermodynamic Properties of Lithium Ion Batteries System: A First Principles Calculations

Year: 2013

Type: article

Abstract: Although density functional theory has played important role in designing electrode materials for lithium ion batteries, it fails in correctly prediction of temperature dependant parameters of performance of the battery system that is more relevant in application. To simulate the temperature dependence of the thermodynamic parameters, the lattice vibrational energy should be included. In this paper, we calculated the lattice vibrational dynamic properties of the LiCoO2/Li half battery system. We found that there is no imaginary frequency appeared when all Li atoms are removed, indicating that the bulk structure is stable upon Li removal. Furthermore, the vibration frequency of Co atom along the ab-plane is substantially increased after lithium is removed, due to the strengthened Co-O bonds. The vibrational entropy of the LiCoO2 and its delithiated state Li□CoO2 is very close to each other. We show that the intercalation potential of the battery is altered noticeable when the lattice vibrational contribution is included.

Source: International Journal of Electrochemical Science

DOI: 10.1016/s1452-3981(23)13130-0