Electrochemically\nTailored Host Design with Gradient\nSeeds for Dendrite-Free Li Metal Batteries

Dendritic challenges in Li metal batteries are commonly\nresolved\nusing porous three-dimensional (3D) current collectors, which have\na significant issue in that Li is deposited from the top (top growth)\nof the structure rather than from the bottom (bottom growth), failing\nto effectively suppress dendrite growth and volumetric expansion.\nWe propose the structure incorporating a gradient lithiophilic seed\nwithin a 3D framework by pulse electroplating Mg, specifically targeting\nthe near bottom to promote bottom growth and achieve dense Li deposition.\nThis method achieves precise control over the catalytic seed size\nand distribution. Optimal conditions for maximizing the catalytic\neffect are identified. The resulting Mg-gradient porous-Cu structure\nexhibits superior Li-plating behavior with bottom growth, significantly\nreducing dendrite formation and improving cycle life. The mechanistic\norigin of bottom-guided Li growth is supported by DFT and 3D simulation\nresults. This method presents a significant step forward in developing\nhigh-performance Li–metal batteries.