Enabling Stable Lithium Metal Anode via 3D Inorganic Skeleton with Superlithiophilic Interphase

Abstract The lithium metal battery (LMB) is among the most sought‐after battery chemistries for high‐energy storage devices. However, LMBs usually undergo uncontrollable lithium deposition and severe side reactions, which significantly impede their practical applications. Herein, a stable Al 2 O 3 ‐based inorganic framework with superlithiophilic lithium aluminum oxide (Li‐Al‐O) interphase is created via reacting Li with Al 2 O 3 nanoparticles. The Al 2 O 3 ‐based inorganic framework can serve as a stable Li “host,” reducing the volume expansion during cell cycling. Moreover, the strong interaction between Li‐Al‐O interphase and Li + can redistribute Li + and reduce the ion concentration gradient near surface protrusion, thus reducing uneven lithium electrodeposition. From galvanostatic measurements, symmetric cells with the 3D Al 2 O 3 ‐hybrid electrode can operate under an ultrahigh current density of 8 mA cm −2 over 480 cycles. When used in full cells, it improves the capacity retention of Li/LiFePO 4 from 78.4% to 93.6% after 200 cycles and enables long‐term operation of Li/Li 4 Ti 5 O 12 for over 1200 cycles.