Molecular tailoring engineering enables stable and efficient chemical pre-lithiation for graphite anodes in lithium-ion batteries

Graphite (Gr) is a low-cost, highly stable anode material for lithium-ion batteries (LIBs). However, the Gr anode has the disadvantage of low initial coulombic efficiency (ICE) due to the loss of active lithium caused by the formation of solid electrolyte interface (SEI). Chemical pre-lithiation is an effective method to compensate for the loss of active lithium, but the redox potential of traditional chemical pre-lithiation reagents is higher than the Li + insertion potential of Gr (≈0.2 V vs Li/Li + ), which leads to the inability of lithiation reaction. In this work, a methoxybiphenyl lithium chemical pre-lithiation system is designed by molecular tailoring engineering, density functional theory (DFT) and experimental investigations demonstrate the system's reduced redox potential (0.075–0.142 V vs Li/Li + ) and a suitable Li + binding energy. The results demonstrate that the ICE of Gr anode chemically pre-lithiated for 4 min is 103.32 % and the process is stable and efficient by using the molecularly tailored chemical pre-lithiation reagent. In practical applications, the lithium-ion full-battery assembled with LiFePO 4 (pGr||LFP) exhibits high ICE (93.05 %) and energy density (321.7 Wh kg −1 ). The novel methoxybiphenyl lithium chemical pre-lithiation system prepared by molecular tailoring engineering provides a promising approach for chemical pre-lithiation engineering.