Lithiophilic Sb surface modified Cu nanowires grown on Cu foam: a synergistic 1D@3D hierarchical structure for stable lithium metal anodes

The uncontrollable lithium (Li) dendrite growth during repeated cycles is a safety risk and is an undesirable electrochemical property of Li metal batteries (LMBs) that hinders the commercialization of LMBs. To realize a dendrite-free Li anode, a hierarchical lithiophilic current collector was fabricated with Sb modified Cu nanowires on Cu foam (1D@3D-Cu/Sb). The 3D porous Cu foam scaffolds have ample space which can buffer the volume changes and provide a reduced local current density. Moreover, the Sb modified 1D Cu nanowires with a secondary structure of an homogenized Li+ flux provide numerous lithiophilic sites for uniform Li+ deposition, further suppressing the Li dendrite formation. Consequently, the 1D@3D-Cu/Sb as a Li host operates for over 900 h with a low overpotential (similar to 11 mV) without intense voltage fluctuation for symmetrical cells. Furthermore, the full cells pairing Li-deposited 1D@3D-Cu/Sb with a LiFePO4 (LFP) cathode achieves promising cycling stability for 200 cycles at 0.5C.

Automated summary

By fabricating a hierarchical lithiophilic current collector, the uncontrollable lithium dendrite growth in lithium metal batteries is effectively suppressed, leading to enhanced cycling stability and safety of the batteries, thus promoting the commercialization process.