Construction of Rectifying Interphase via Quasi‐PN Junction Effect for Uniform Lithium Deposition in Lithium Metal Batteries

ABSTRACT The controllable regulation of the SEI is pivotal to solve the problem of Li dendrite growth for high‐performance LMBs, yet its achievement is constrained by the difficulty in dynamic synergistic matching of ion and electron fluxes. Herein, based on the rectification principle of diodes, a quasi‐PN junction composed of a BP loaded Li anode (P‐type) and an ATO‐coated separator (N‐type) is constructed in the separator/anode interface, creating a “rectifying interphase” to achieve uniform lithium deposition in LMBs. During battery operation, the RI layer can block electron transport and enhance Li + flux, thereby reducing the initial nucleation sites of Li and facilitating the rapid migration of Li + . The as‐formed multiphase SEI layer exhibits both high mechanical strength and efficient Li + transport capability, effectively suppressing side reactions. Remarkably, the NCM811||Li cells with the RI deliver an initial capacity of 175.51 mAh g −1 and a capacity of 121.77 mAh g −1 after 900 cycles at 0.5 C. In addition, they exhibit a high energy density of 640.88 Wh kg −1 (calculated based on the mass of cathode active material and twice the theoretical mass of anode active material) and high‐safety performance. This work provides a new insight for the interface optimization of high‐performance battery systems.