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The performance of lithium‐metal batteries is severely hampered by uncontrollable dendrite growth and volume expansion on the metal anodes. Inspired by the "blockchain" concept in data mining, here we utilize a conductive polymer‐filled metal–organic framework (MOF) as the lithium host, in which polypyrrole (PPy) serves as the "chain" to interlink Li "blocks" stored in the MOF pores. While the N‐rich PPy guides fast Li+ infiltration/extrusion and serves as the nucleation sites for isotropic Li growth, the MOF pores compartmentalize bulk Li deposition for 3D matrix Li storage, leading to low‐barrier and dendrite‐free Li plating/stripping with superb Coulombic efficiency. The as‐fabricated lithium‐metal anodes operate over 700 cycles at 5 mA cm−2 in symmetric cells, and 800 cycles at 1 C in full cells with a per‐cycle capacity loss of only 0.017 %. This work might open a new chapter for Li‐metal anode construction by introducing the concept of "blockchain" management of Li plating/stripping. [ABSTRACT FROM AUTHOR]

One of the key challenges in achieving practical lithium–air battery is the poor moisture tolerance of the lithium metal anode. Herein, guided by theoretical modeling, an effective tactic for realizing water‐resistant Li anode by implementing a wax‐assisted transfer protocol is reported to passivate the Li surface with an inert high‐quality chemical vapor deposition (CVD) graphene layer. This electrically conductive and mechanically robust graphene coating enables serving as an artificial solid/electrolyte interphase (SEI), guiding homogeneous Li plating/stripping, suppressing dendrite and "dead" Li formation, as well as passivating the Li surface from moisture erosion and side reactions. Consequently, lithium–air batteries fabricated with the passivated Li anodes demonstrate a superb cycling performance up to 2300 h (230 cycles at 1000 mAh g−1, 200 mA g−1). More strikingly, the anode recycled thereafter can be recoupled with a fresh cathode to continuously run for 400 extended hours. Comprehensive time‐lapse and ex situ microscopic and spectroscopic investigations are further carried out for elucidating the fundamentals behind the extraordinary air and electrochemical stability. [ABSTRACT FROM AUTHOR]