Wettable carbon felt framework for high loading Li-metal composite anode

Li metal anode has received extensive attention due to its high specific capacity and low potential vs. Li/Li+ for lithium batteries. However, dendrite growth, volume change and "dead" Li formation during cycling hinder its practical application. Here we report an innovated cuprite-coated carbon felt as current collector, with ultralight 3D framework and significantly improved Li-metal loading through thermal infusion. The Li-metal anode has a high Li content of 90 wt.%. The cuprite coating improves the lithiophilicity of carbon felt remarkably, due to the surface affinity reaction between cuprite and Li. The porous carbon felt provides good electronic connection and buffer space to accommodate volume change during Li stripping/plating. It leads to uniformly distributed local current density and preference of Li stripping/plating in the highly dispersed concave areas, with suppressed formation of dendrites and “dead” Li. The Li composite electrode shows excellent cycle stability with low polarization in both symmetric and full cells. This work opens a new approach for the development of high loading Li composite anodes for advanced Li metal batteries.