Lithium–Carbon Composite Anodes for Solid-State Lithium Metal Batteries

While various carbon materials have been reported to make composite lithium metal anodes (LMAs) for liquid-electrolyte batteries, transferring the success to solid-state batteries has proven challenging. Here, we investigate the Li cycling performance of composite LMAs with four representative carbon materials, including carbon black, carbon nanotubes, ordered mesoporous carbon, and graphite. While most carbon materials can demonstrate comparable or better performance than planar Li foil, graphite exhibits the best electrochemical performance in terms of Li cycling. An almost 2-fold increase in the critical current density can be achieved at room temperature after the incorporation of graphite in Li metals due to improvement in the interfacial contact between the anode and the solid electrolyte during Li stripping. The results suggest the effective role of graphite over other types of carbon materials in improving the transport of Li atoms in composite Li anodes for solid-state battery applications.