Lithium dendrite inhibition via 3D porous lithium metal anode accompanied by inherent SEI layer

Abstract

Lithium (Li) metal anodes have been considered as the ultimate anode materials for the next-generation rechargeable batteries. However, uneven dendrite formation and anode volume expansion still can put a brake on the development of Li metal anode. Here, freestanding three-dimensional Li metal foam accompanied by inherent solid electrolyte interphase (SEI) capsulation formed by template-free chemical etching is constructed to promote the uniform lithium deposition and suppress dendritic Li growth. Contrary to planar Li metal foil, the 3D porous Li matrix can buffer the volume change and guide Li deposition inside its porous structure. Moreover, the encapsulated artificial SEI layer, which efficiently uniform the diffusion of Li ions on the interface, enables deeply deposited Li metal. Benefiting from the unique deposition kinetics, the Li plating/stripping process based on our strategy can be deeply cycled at various current densities with low overpotential between 1.0 and 20.0 mA cm−2 and achieve long lifetime up to 350 h. Moreover, Li metal batteries with LiNiCoMnO2 (Ni:Co:Mn=1:1:1) cathode exhibit excellent electrochemical performance at high current density and active material loading for more than 20.4 mg cm−2. In terms of both porous Li matrix and inherent dense SEI layer, our cell greatly suppresses the gassing process and reduces heat generation, further demonstrating the reliability and security of the batteries.