High‐Performance Hydrogen‐Aided Sn‐Air Battery

ABSTRACT The growing demand for energy storage has driven the need for secure, cost‐effective batteries. Although aqueous tin‐air batteries (SnABs) offer high theoretical energy density and intrinsic safety, their commercialization faces significant challenges due to high charging overpotential and limited cycle life, primarily caused by sluggish oxygen evolution reaction (OER) kinetics. Here, a hydrogen‐aided Sn‐air battery (Sn‐HAB) is reported, which replaces the sluggish OER with an efficient hydrogen oxidation reaction (HOR) at the cathode during charging, substantially reducing the overpotential. Moreover, a tinophilic brass mesh (BM) substrate is introduced to regulate Sn deposition, enabling a dense and dendrite‐free morphology at 100 mA cm −2 . As a result, the Sn‐HAB operates from 0 to 1000 mA cm − 2 , achieving a charging voltage of 1.0 V (versus 2.5 V for SnABs at 100 mA cm − 2 ) and a cycle life exceeding 900 cycles—nearly 20 times longer than conventional SnABs. An anode‐free (without bulk Sn) configuration maintains stable operation for over 800 cycles, and ampere‐hour‐level cells demonstrate scalability. This work overcomes the rate and efficiency limitations of SnABs, establishing a pathway toward safe, low‐cost aqueous energy storage systems.