Prelithiation plays a crucial role in advancing the development of high-energy-density batteries, and ultrathin lithium (UTL) has been proven to be a promising anode prelithiation reagent. However, there remains a need to explore an adjustable, efficient, and cost-effective method for manufacturing UTL. In this study, we introduce a method for producing UTL with adjustable thicknesses ranging from 1.5 to 10 μm through blade coating of molten lithium on poly(vinylidene fluoride)-modified copper current collectors. By employing the transfer-printing method, prelithiated graphite and Si-C composite electrodes are prepared, which exhibit significantly improved initial Coulombic efficiencies of 99.60% and 99.32% in half-cells, respectively. Moreover, the energy densities of Li(NiCoMn)1/3O2 and LiFePO4 full cells assembled with the prelithiated graphite electrodes increase by 13.1% and 23.6%, respectively.
Keywords: lithiophilicity; lithium-ion battery; prelithiation; surface modification; ultrathin lithium.