TiO₂/Cu₂O heterostructure enabling selective and uniform lithium deposition towards stable lithium metal anodes

Lithium (Li) metal is the ultimate anode choice for next generation high energy density batteries. However, the high nucleation energy barrier and nonuniform electric field distribution, as well as huge volume expansion, lead to the uncontrollable growth of Li dendrites and poor utilization of Li metal, which hinders its practical application. Herein, titanium dioxide/cuprous oxide (TiO₂/Cu₂O) heterostructure is constructed on the rimous skeleton of Cu mesh, and the heterostructure decorated rimous Cu mesh (H-CM) can act as both current collector and host for dendrite-free Li metal anode. The TiO₂/Cu₂O heterostructure realizes selective Li nucleation by nano TiO₂ and then induces fast and uniform Li conduction with the aid of heterostructure interface and nano Cu₂O contributing to dendrite-free Li deposition. While the internal and external space of rimous skeletons in H-CM is used to accommodate the deposited Li and buffer its volume change. Therefore, the cycling reversibility of the derived Li metal anode in H-CM is improved to a high Coulombic efficiency of 98.8% for more than 350 cycles at a current density of 1 mA·cm⁻², and 1,000 h (equals to 500 cycles) stable repeated Li plating/stripping can be operated in a symmetric cell. Furthermore, full cells with limited Li anode and high loading LiFePO₄ cathode present excellent cycling and rate performances.