Binding Energy-Assisted Oxidation Potential as a Measure of Prelithiation Capability

The solution-based chemical prelithiation of electrode materials is an effective approach to elevate the initial coulombic efficiency (ICE) and energy-density of the Li-ion battery. Although various lithium-aromatic compound complex solutions (LACSs) have been reported as prelithiation reagents, fundamental understandings are still lacking regarding their drastic difference in prelithiation behavior. In this work, the rate-determining step and some key factors that affect the prelithiation capability were recognized via electrochemical evaluation, spectroscopic analysis, and density functional theory (DFT) calculations. Considering the inherent correlations between the potential of electrochemical Li⁺-extraction from LACS upon cyclic voltammetry (the oxidation potential of LACS, E_O), the calculated highest occupied molecular orbital (HOMO) energy level, the binding energy (BE) of the solvated Li-ions to the solution (BE_solution), and the prediction accuracy of prelithiation capability and calculations efficiency, we proposed BE-assisted E_O as a descriptor for its prelithiation feasibility. This strategy will provide important guidance for the rapid selection and rational design of LACSs for efficient chemical prelithiation.