Self‐smoothing lithium metal anode based on screen‐printed Cu‐mesh current collector for long‐term safety of lithium metal batteries

Abstract Lithium metal is an attractive anode candidate to enable high‐energy lithium battery systems. However, nonideal dendrite growth at the anode/separator interface hinders the safe application of lithium metal batteries (LMBs). Three‐dimensional (3D) current collectors (CCs) with high specific surface area could afford a crucial effect on suppressing dendrites, yet still subject to large thickness/weight and limited scalability for large‐area fabrication. Here, we show an industry‐compatible screen‐printing technique to prepare ultrathin (∼1.5 μm) and ultralight (∼0.54 mg cm −2 ) Cu mesh on commercial Cu foil to realize a long‐term safety of LMBs. In contrast to conventional laboratory level techniques, the screen‐printed Cu‐mesh CCs (∼8.3 mg cm −2 ), which are even lighter than the original Cu foil (∼8.84 mg cm −2 ), show a high compatibility for large‐area fabrication. Meanwhile, the periodic Cu mesh can be also used to regulate the homogeneous distribution of Li‐ion flux and thus, be in favor of realizing self‐smoothing anodes at even deep and fast plating/stripping of lithium. The resulting lithium anodes demonstrate a long‐term cyclic life of ∼840 h at 1 mA cm −2 with a high Coulombic efficiency of 97.5%. LMBs with Cu‐mesh CCs exhibit outstanding capacity retentions of ∼87% after 350 cycles at 1 C and ∼80% after 200 cycles at 5 C, suggesting a significant step of printable 3D CCs toward practical application of high‐energy LMBs.