Lithium metal anode on a copper dendritic superstructure

Li-metal is one of the most promising anode materials for electrochemical energy storage. However, the growth of Li dendrites during electrochemical deposition leads to low Coulombic efficiency and safety concerns and has long hindered the application of rechargeable Li-metal batteries. In this study, we designed a Cu dendritic superstructure with macropores as an anode-free three-dimensional current collector, which can significantly improve the electrochemical plating/stripping behavior of Li. The Li-metal anodes are accommodated by a Cu dendritic superstructure with no uncontrollable Li dendrites. This anode can operate for more than 600 h without a short-circuit and exhibits a low level of voltage hysteresis (~20 mV). The anode-free dendritic superstructure demonstrates exceptional performance and highlights the importance of rational design for a current collector that can accommodate Li anodes and provide a long lifespan.