Metal Anodes with Ultrahigh Reversibility Enabled by the Closest Packing Crystallography for Sustainable Batteries

Abstract The ever‐growing annual electricity generated from sustainable and intermittent energy such as wind and solar power requires cost effective and reliable electrochemical energy storage. Rechargeable batteries based on multivalent metal anodes such as Zn, Al, and Fe, taking advantage of large‐scale production and affordable cost, have emerged as promising candidates. However, the uncontrollable dendrite‐like metal deposition on regular substrate caused by disordered metal crystallization usually leads to premature failure of batteries and even safety concerns when the dendrite bridges the electrodes. Here it is reported that a series of metal anodes (Zn, Co, Al, Ni, and Fe) with multiple crystal structures (hexagonal close‐packed, face‐centered cubic, and body‐centered cubic) can achieve dendrite‐free and epitaxial deposition on single‐crystal Cu(111) substrates enabled by the closest packing crystallography. Moreover, the closest packed facets are aligned horizontally with the substrates, resulting in compact planar construction and excellent chemical stability even at an unprecedented current density of 1 A cm⁻². The full cells under a practical anode‐to‐cathode capacity ratio of 2.3 show a cycling life span of over 800 cycles with Coulombic efficiency of > 99.9%. The universal approach of regulating metal electrodeposition in this work is expected to boost the development of emerging sustainable energy storage/conversion devices.