One-Step Stacking Armor Current Collectors for Dendrite-Free Lithium Metal Batteries

Li metal is a promising anode for high-energy-density batteries, suffering from rapid capacity fading and uncontrolled volume expansion. Herein, an innovative method is employed to fabricate a 3D current collector. Laser processing is used to form through-holes on ultrathin Cu foil, which is integrated with Cu foam by one-step stacking. A hybrid copper composite (HCC) current collector is constructed efficiently. Through-holes serve as guided channels, promoting inward deposition to the bottom Cu foam. Owing to the high surface area and interconnected porous network, Cu foam offers ample space and reaction interfaces. A synergistic effect enables precise regulation of deposition behavior, effectively suppressing uncontrolled dendrite growth and volume expansion. The HCC half cell enables stable Li plating/stripping for 580 cycles with CE exceeding 98.2% at 0.5 mA cm^-2. For a full cell assembled with a commercial LiFePO₄ cathode, it maintains an 82% capacity retention rate after 280 cycles at 2 C, providing a promising pathway toward practical applications.