Thermally Conductive AlN‐Network Shield for Separators to Achieve Dendrite‐Free Plating and Fast Li‐Ion Transport toward Durable and High‐Rate Lithium‐Metal Anodes

Abstract Lithium‐metal anodes suffer from inadequate rate and cycling performances for practical application mainly due to the harmful dendrite growth, especially at high currents. Herein a facile construction of the porous and robust network with thermally conductive AlN nanowires onto the commercial polypropylene separator by convenient vacuum filtration is reported. The so‐constructed AlN‐network shield provides a uniform thermal distribution to realize homogeneous Li deposition, super electrolyte‐philic channels to enhance Li‐ion transport, and also a physical barrier to resist dendrite piercing as the last fence. Consequently, the symmetric Li|Li cell presents an ultralong lifetime over 8000 h (20 mA cm −2 , 3 mAh cm −2 ) and over 1000 h even at an unprecedented high rate (80 mA cm −2 , 80 mAh cm −2 ), which is far surpassing the corresponding performances reported to date. The corresponding Li|LiFePO 4 cell delivers a high specific capacity of 84.3 mAh g −1 at 10 C. This study demonstrates an efficient approach with great application potential toward durable and high‐power Li–metal batteries and even beyond.