Tailored Hierarchical Porous Copper Architectures via Three Dimensional Printing and Pressure‐less Sintering for Next‐Generation Lithium‐Metal Batteries

As the demand for safer, higher‐energy batteries continues to rise, researchers are looking beyond graphite, whose capacity is capped at 372 mAh g −1 . Lithium metal stands out with its exceptional capacity of 3860 mAh g −1 and very low reduction potential, but its practical use is hampered by dendrite growth, unstable interfaces, and large volume changes. Structural modification of copper current collectors is a promising strategy to stabilize lithium metal anodes. Three‐dimensional (3D) porous architectures can homogenize current distribution and suppress dendrite growth, yet their fabrication via combined 3D printing and pressureless sintering remains unexplored. In this study, a new fabrication approach is presented that combines 3D printing with pressureless sintering to create a hierarchical porous copper current collector. The interconnected pores guide lithium to deposit inside the structure, lowering the chance of dendrite‐induced short circuits. The large surface area helps reduce nucleation barriers and promotes a uniform SEI, which in turn improves cycling stability. Compared to conventional copper foil, the porous design shows faster charge transfer and greater structural integrity during repeated lithium plating and stripping. Ex situ characterizations and surface morphology analyses further validate its ability. Overall, this method opens a pathway toward more reliable and high‐performance lithium metal anodes.