Addition of aluminum lactate in electrolyte promotes (002)-textured zinc growth and suppresses side reactions in zinc-ion batteries

Aqueous zinc-ion batteries (AZIBs) suffer from interfacial instability mainly due to the inherent electrochemical incompatibility between zinc anodes and aqueous electrolytes. Herein, we report aluminum lactate (Al-Lac) as an effective electrolyte additive that stabilizes zinc anodes via comprehensive solvation structure regulation. Al-Lac competitively coordinates with water molecules via Al 3+ and lactate ions, disrupting the original [Zn(H 2 O) 6 ] 2+ solvation sheath, reducing water activity, and suppressing hydrogen evolution. Furthermore, Al 3+ preferentially adsorbs onto the Zn surface under an electric field, establishing a protective electrostatic shield that guides uniform Zn 2+ deposition. As a result, the nucleation overpotential of Zn 2+ is significantly reduced, Zn deposition is oriented preferentially along the (002) plane, and dendrite growth is effectively inhibited. Consequently, the introduction of Al-Lac effectively enhances the interfacial reaction kinetics during Zn deposition and maintains the interfacial impedance. The corresponding Zn||Zn symmetric cells achieve an ultra-long lifespan of 5000 h (2 mA cm −2 , 1 mAh cm −2 ), and full-cells with Na 2 V 6 O 16 ·2.74H 2 O cathodes exhibit negligible capacity decay after 2000 cycles at 10 A g −1 . This work provides a feasible strategy for the development of low-cost and high-stability AZIBs. Aluminum lactate regulates the competitive solvation structure and builds an electrostatic shield, enabling (002)-textured zinc deposition and long lifespan for aqueous zinc-ion batteries. Download: Download high-res image (155KB) Download: Download full-size image