Built‐In Electric Field of In Situ Formed Artificial Interface Layer Induces Fast and Uniform Sodium‐Ions Transmission to Achieve a Long‐Term Stable Sodium Metal Battery Under Harsh Conditions

Sodium metal batteries (SMBs), the next‐generation advanced secondary batteries, have attracted extensive attention due to their low cost and high energy density. However, the unavoidable interfacial side reactions and uncontrollable dendrite growth severely restrict their practical application. In this work, a Na (100)‐textured composite anode embedded with antimony‐doped tin oxide (ATO) nanoparticles (ATO‐12Na) is innovatively designed via an accumulative roll bonding technique. It is observed that the Na (100) texture not only contributes to the formation of anion‐derived inorganic‐rich solid electrolyte interphase layer on the surface of ATO‐12Na composite anode but also efficiently induces the uniform and horizontal Na deposition during the pre‐deposition stage. Profiting from the intrinsic Na affinity of Na (100) texture and the high sodiophilicity of ATO active sites, the integrated composite anode exhibits enhanced interfacial compatibility and excellent Na plating/stripping stability. At 2 mA cm−2, the ATO‐12Na symmetric cell can operate steadily for more than 1400 h. The full cell assembled by ATO‐12Na anode and Na3V2(PO4)3 cathode delivers impressive long‐term cycling stability over 4500 cycles at 500 mA g−1 with a high capacity retention of 80.7%. This study offers a new approach to designing ultra‐stable, dendrite‐free, and high‐performance SMBs.

Na (100)‐Textured Electrode Embedded with Sb‐Doped SnO₂ Nanoparticles for Dendrite‐Free Sodium Metal Batteries

Li,

Miao,

Lin

et al. 2024

Highly Stable Sodium Metal Batteries Enabled by Manipulating the Fluorinated Organic Components of Solid‐Electrolyte‐Interphase

Wang,

Dai,

et al. 2024

Na metal batteries (NMBs) stand at the forefront of advancing energy storage technologies, but are severely hampered by Na dendrite issues, especially when using carbonate electrolytes. Suppressing the growth of Na dendrites through constructing NaF‐rich solid‐electrolyte‐interphase (SEI) is a commonly‐used strategy to prolong the lifespan of NMBs. In contrast, fluorinated organic SEI components are often underutilized. Inspired by unveiling the adsorption configuration of fluorinated organic compounds on the surface of Na metal, an optimized SEI architecture for stabilizing NMBs is proposed by investigating the C4H9SO2F‐/C4F9SO2F‐treated Na metal anodes. It is revealed that the SEI built on a fluorinated inorganic/organic hybrid layer exhibit favorable Na passivation capability, significantly improving Na deposition behavior. As a result, the NMB with a high‐loading cathode (15 mg cm−2) and a negative/positive capacity ratio (N/P) ratio of 4 shows a long‐term life span over 1000 cycles with 92.8% capacity retention at 2 C. This work opens a new pathway for developing robust and high‐energy‐density NMBs.

Conformal Sodium Deposition Facilitated by Ion Adsorption‐Intercalation Process within Hetero‐Interface for Stable Sodium Metal Batteries

Wang,

Zuo,

Wang

et al. 2024

Sodium (Na) metal battery is regarded as one of the most promising candidates for large‐scale energy storage devices, benefiting from the abundant sodium reserves and low cost. However, its practical application is hindered by the dendrite growth and unstable electrode‐electrolyte interface. Herein, a 3D sodiophilic structure composed of a carbon matrix overlaid with g‐C3N4 coating layers (g‐C3N4/3D‐C) is designed to stabilize the Na plating/stripping behavior. The sodiophilicity is endowed by a highly reversible adsorption‐intercalation process at the hetero‐interface, which can guide conformal Na deposition and induce the formation of inorganic‐rich solid‐electrolyte interphases with high structural stability and fast Na‐ion transport. Meanwhile, the 3D scaffold can effectively accommodate Na deposition during Na plating/stripping and depress the dendrite formation. As a result, the half cell assembled with g‐C3N4/3D‐C electrode delivers long‐term cycling performance at 1.0 mA cm−2 with a high Coulombic efficiency of 99.92% for over 2000 cycles and of 99.94% even at 5 mA cm−2, 10 mAh cm−2. The practical feasibility of the g‐C3N4/3D‐C is verified with full cells, which shows favorable rate capability and long‐cycle performance. The sodiophilic hetero‐interface construction strategy proposed in this work sparks new insights for designing high‐performance Na metal anodes.