Ni/Graphdiyne composites inhibit dendrite growth in lithium metal anodes

Abstract

The growth of lithium dendrites during repeated deposition or dissolution is a key issue that inhibits lithium metal anodes for high energy density batteries. Here, we demonstrate nickel-anchored graphdiyne materials by solvothermal method on three-dimensional copper foam and apply them to Li metal deposition and stripping. The graphdiyne has a very high Li storage capacity, but poor Li affinity. On the other hand, Ni is highly lithiophilicity and the rich nanoporous structure of graphdiyne provides a stable Li deposition interface, enabling high-efficiency and high-capacity Li deposition and stripping. Ni-anchored graphdiyne modified copper foam substrate can achieve high-area, high-rate dendrite-free Li deposition and stripping. The deposition and stripping of 1 mA h cm−2 of lithium at a current density of 1 mA cm−2 show an overpotential of about 12 mV, high cycle efficiency of 98.5%, and a cycle time of up to 2200 h. The cycle efficiency can reach 98% at higher current density and higher lithium deposition and stripping amount. We assemble a full battery with Ni/GDY@Li using LiFePO4 as the cathode material, showing excellent capacity and cycling stability.