Lifecycle Synergistic Prelithiation Strategy of Both Anode and Cathode for High-Performance Lithium-Ion Batteries

Abstract

Prelithiation is recognized as an effective technology for addressing the depletion of active lithium, but conventional methods are constrained by their reliance on singular lithium replenishment mechanisms and limited functionality. Herein, a synergistic and comprehensive lifecycle prelithiation technology is introduced as applicable to both anode and cathode. For anode prelithiation, highly reactive biphenyl lithium is leveraged as a lithium replenishing agent, supplemented by functional additives, ethoxy(pentafluoro)cyclotriphosphazene (PFPN) and fluoroethylene carbonate (FEC), to generate a robust SEI enriched with Li₃N, LiF, Li₃P and Li₂O. This approach not only compensates for the initial active lithium loss but also fortifies the structural integrity of the SEI. For cathode prelithiation, the high-capacity lithium replenisher Li₂C₂O₄ and Li₂C₄O₄ comprising B, N double-doped carbon loaded Mo₂C-W₂C (Mo-W@BNC) heterogeneous catalysts is employed, which exhibits superior catalytic performance in facilitating the release of lithium. The exceptional efficient liberations of lithium are achieved at discharge voltages of 3.78 V and 4.14 V for Li₂C₂O₄ and Li₂C₂O₄, respectively. The prelithiation for both anode and cathode mitigates the initial active lithium loss by 22.6%. Moreover, a singular activation during subsequent usage contributes an additional 0.8 mAh cm⁻² of active lithium, achieving a capacity retention of 99.3% after 250 cycles at 0.5C.