Lithiophobic-lithiophilic composite architecture through co-deposition technology toward high-performance lithium metal batteries

Metallic lithium (Li) has been acclaimed as the most promising anode materials for lithium batteries due to its ultrahigh theoretical capacity of 3860 mA h g⁻¹. Its practical application is impeded, however, due to the notorious problems related to dendrite growth caused by its uneven current density distribution and high Li nucleation overpotential. Here, we report a three-dimensional (3D) lithiophobic phase (Cu) and lithiophilic phase (Zn or Sn) composite architecture realized through a facile electrochemical co-deposition technology and its use as a scaffold for dendrite-free Li metal anode. It is found that the simultaneous formation of this lithiophobic-lithiophilic composite on Cu foam leads to ultrafine lithiophilic phase (20 nm) and reduced Li nucleation overpotential, as well as enhanced homogeneity, which enables a uniform electric field distribution during lithium plating/stripping, thus facilitating even and dendrite-free Li deposition. In the meanwhile, the lithiophobic component in the composite acts as a strong backbone, helping to maintain structural stability during lithium storage. Also, the as-prepared three-dimensional micro/nanoporous scaffold with large surface area can effectively reduce the local current density and suppress Li dendrite growth. The full cells with the composite architecture/Li as anode and LiFePO₄ as cathode show promising electrochemical performance with over 80% capacity retention over 1600 cycles at 5 C. This work broadens the horizon of lithiophilic hosts for next-generation high-performance Li metal batteries. © 2019 Published by Elsevier Ltd.