This study reports an ambient-air-tolerant approach for negative electrode prelithiation by using 1 M lithium-biphenyl (Li-Bp)/tetrahydrofuran (THF) solution as the prelithiation reagent. Key to this strategy are the relatively stable nature of 1 M Li-Bp/THF in ambient air and the unique electrochemical behavior of Bp in ether and carbonate solvents. With its low redox potential of 0.41 V vs Li/Li+, Li-Bp can prelithiate various active materials with high efficacy. The successful prelithiation of a phosphrous/carbon composite electrode and the notable improvement in its initial Coulombic efficiency (CE) demonstrates the practicality of this strategy.
Keywords: ambient air; biphenyl; lithium-ion batteries; negative electrode; prelithiation.