Self-Organized Core-Shell Composite Electrodes for Copper-Free and Dendrite-Free Lithium Metal Batteries with Ultrahigh Energy Density

Lithium metal (Li) is appealing anode material that provides the highest capacity and the lowest electrochemical potential to lithium battery. However, the easy formation of lithium dendrites during the charge/discharge process largely hinders its application. Reported approaches to suppressing the dendrites formation often scarify the energy density of the battery. We report here an energy-enhancing strategy to achieve dendrite-free and long-term stable Li anode. A self-organized core-shell composite anode, comprising of an outer shell of lithiation liquid metal (LixLMy) and an inner layer of Li, is developed. The composite anode (LixLMy) processes high electrical and ionic conductivity, isolates Li from the electrolyte, and inhibits the growth of Li dendrites. Full cells made of composite anodes and commercially available NCM622 cathodes show ultrahigh energy density of 1500 Wh L–1 (483 Wh kg–1), and a high capacity retention per cycle of 99.95% over more than 500 cycles.