Effective Strategy for Enhancing the Performance of Li₄Ti₅O₁₂ Anodes in Lithium-Ion Batteries: Magnetron Sputtering...

The interface between the current collector and active material is the primary interface of charge transfer. Herein, we designed an effective strategy to optimize the interface architecture by depositing molybdenum disulfide on the copper foil surface (Cu-MoS₂) via magnetron sputtering. The Cu-MoS₂ is directly used as a current collector and supports the Li₄Ti₅O₁₂ anode (Cu-MoS₂-LTO). Typically, after being cycled at 1 A g^-1 for 300 cycles, the capacities of the Cu-LTO cell and Cu-MoS₂ cell are about 114.94 and 128.35 mA h g^-1, respectively, whereas the capacity of the Cu-MoS₂-LTO cell is as high as 373.9 mA h g^-1 with a capacity retention rate of 89.1%. The MoS₂ not only optimizes the interfacial architecture but also provides an additional capacity contribution to the Cu-MoS₂-LTO cell. Based on scanning electron microscopy and X-ray photoelectron spectroscopy test analysis, we propose a dual interface model. It is revealed that the molybdenum disulfide film can significantly improve the charge-transfer efficiency and uniformity of the interface, reduce internal resistance of the batteries, prevent oxidation of the copper foil, and thereby improve the chemical stability of the current collector. In addition, magnetron sputtering technology has large-scale productivity and greatly enhances the industrial application of this strategy.