Enabling Lithium-Metal Anode Encapsulated in a 3D Carbon Skeleton with a Superior Rate Performance and Capacity Retention in Full Cells

Suppressing the formation of lithium (Li) dendrites is central to implementing Li-metal anode, which has gained growing attention due to its ultrahigh specific capacity and low redox potential. Here, a novel approach is adopted to deposit Li-metal within a rigid three-dimensional (3D) carbon paper (3DCP) network, which consists of a cross-link framework of carbon fibers and graphene nanosheets (GNs). This unique structure yields a uniform distribution of Li-nuclei during the preliminary stage of Li-plating and the formation of a stable solid-electrolyte interface. The as-obtained anode can deliver a high areal capacity of 10 mAh cm^-2 without the dendritic formation after 1000 cycles in a Li@3DCP/LiFePO₄ full cell at 4 C. In addition, the Li@3DCP anode displays low voltage platform (<20 mV at 1 mA cm^-2), high plating/stripping efficiency (99.0%), and long lifespan (>1000 h). When coupled with LiNi_0.8Co_0.15Al_0.05O₂ cathode, the Li@3DCP electrode exhibits a superior rate capability up to 10 C and high temperature performance (60 °C). The unprecedented performance is attributed to the desirable combination of micro/nanostructures in 3DCP, in which carbon fiber framework provides the mechanical stability for volume change, whereas numerous lithiophilicity sites on GNs enable the suppression of Li-dendrite growth.