(312d) First-Principles Density Functional Theory Modeling of Li Binding: Thermodynamics and Redox Properties of Quinone Derivatives for Lithium-Ion Batteries

First-Principles
Density Functional Theory Modeling of Li Binding: Thermodynamics and Redox
Properties of Quinone Derivatives for Lithium-Ion Batteries

Ki Chul Kim,¹ Tianyuan Liu,²
Seung Woo Lee,² and Seung Soon Jang¹

¹School of Material
Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive NW,
Atlanta, GA 30332-0245, USA

²G. W. Woodruff School
of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive NW,
Atlanta, GA 30332-0405, USA

Abstract

The
Li-binding thermodynamics and redox potentials of seven different quinone
derivatives are investigated to determine their suitability as positive
electrode materials for lithium-ion batteries. First, using density functional
theory (DFT) calculations on the interactions between the quinone derivatives
and Li atoms, we find that the Li atoms primarily bind with the carbonyl groups
in the test molecules. Next, we observed that the redox properties of the
quinone derivatives can be tuned in the desired direction by systematically
modifying their chemical structures using electron-withdrawing functional
groups. Further, DFT-based investigations of the redox potentials of the
Li-bound quinone derivatives provide insights regarding the changes induced in
their redox properties during the discharging process. The redox potential
decreases as the number of bound Li atoms is increased. However, we found that
the functionalization of the quinone derivatives with carboxylic acids can
improve their redox potential as well as their charge capacity. Through this
study, we also determined that the cathodic activity of quinone derivatives
during the discharging process relies strongly on the solvation effect as well as
on the number of carbonyl groups available for further Li binding.