Lithiophilic 3D Copper‐Based Magnetic Current Collector for Lithium‐Free Anode to Realize Deep Lithium Deposition

Abstract Lithium metal is the ideal anode material for high‐energy‐density lithium‐based batteries. Nevertheless, lithium metal tends to accumulate on the surface of the current collector during the plating and stripping process to form lithium dendrites, resulting in low Coulombic efficiency and safety issues. Here, a lithiophilic 3D copper‐based magnetic current collector is designed by loading ferromagnetic nickel–cobalt alloy and lithiophilic zinc oxide onto the copper foam to create a lithium‐free anode. Under the micromagnetic field, the novel lithium‐free anode achieves a high level of deep lithium deposition (from 300 µm to about 1000 µm), successfully alleviating the large change of lithium volume. In addition, the Coulombic efficiency and cyclic stability are improved effectively. With a total capacity of 1 mA h cm −2 at a current density of 1 mA cm −2 , the Coulombic efficiency of the above remains 95% at 590th‐cycle. Moreover, the symmetric cell can stably cycle for more than 560 h at 2 mA cm −2 with the capacity of 1 mA h cm −2 . This novel strategy will potentially open up new horizons for lithium‐free anodes, which may be generalized to other advanced energy storage systems.