Bilayer carbon-based structure with the promotion of homogenous nucleation for lithium metal anodes

Lithium metal anodes (LMAs) are considered as the promising alternatives for next-generation high energy density batteries, but are still hampered by the severe growth of uncontrollable lithium dendrites. The growth of lithium dendrites induces poor cycling lifespan and serious safety concerns, dragging lithium metal batteries out of practical applications. We designed a bilayer carbon-based structure covered with Co/C nanosheets and vertical graphene sheets (VGS). The enormous specific surface area and uniformly distributed Co nanoparticles of the CC@Co/C-VGS host are derived from its unique design, which can reduce local current density and nucleation overpotential, resulting in a dendrite-free morphology and exceptional cycling stability. Symmetric cells exhibit over 400 cycles (800 h) at a high current density/capacity of 10 mA cm−2/10 mA h cm−2. Full cells using LiFePO4 as the cathode have an enhanced rate capability and a prolonged lifespan, reaching 90 mA h g−1 after 1000 cycles at 2 C with 73.5% capacity retention. This unique design sheds light on developing high-performance LMAs.