Direct growth of 3D host on Cu foil for stable lithium metal anode

Abstract

Featuring light weight and high specific capacity, lithium (Li) metal anode has been regarded as the “Holy Grail” for lithium-ion based batteries. The barriers in terms of mossy and dendritic Li formation and infinite volume expansion should be overcome before its application in practice. Herein, we propose a three-dimensional (3D) CNT host on Cu foil, serving as an integrated electrode (C-host@Cu) to stabilize Li metal cyclic behavior. The 3D host is prepared by growing CNT sponge on the Cu substrate directly and seamlessly. Stable cycling with high Coulombic efficiency of ~ 99% is achieved at a current density of 1 mA/cm2 over 250 cycles. In contrast, the bare Cu electrode presents a mossy-like Li morphology with a low Coulombic efficiency of ~ 60% after 150 cycles. The results reveal that the effective manipulation of Li deposition in this unique 3D host successfully suppresses the growth of Li dendrites.