Promoting Preferential\nZn (002) Deposition with a\nLow-Concentration Electrolyte Additive for Highly Reversible Zn-Ion\nBatteries

Aqueous zinc-ion batteries have promising potential as\nenergy storage\ndevices due to their low cost and environmental friendliness. However,\ntheir development has been hindered by zinc dendrite formation and\nparasitic side reactions. Herein, we introduce a low-concentration\nsodium benzoate (NaBZ) electrolyte additive to stabilize the electrode–electrolyte\ninterface and promote deposition on the Zn (002) crystal plane. From\nexperimental characterization and computational analyses, NaBZ was\nfound to adsorb on the Zn surface and inhibit side reactions while\nguiding homogeneous Zn deposition on the (002) plane. Consequently,\nZn|Zn symmetric cells with the NaBZ additive cycled stably for over\n1000 h at a current density of 0.5 mA cm<sup>–2</sup> and an\nareal capacity of 0.5 mAh cm<sup>–2</sup>, while Zn|Cu cells\nshowed excellent reversibility with a Coulombic efficiency of 99.05%.\nMoreover, Zn|Na<sub>0.33</sub>V<sub>2</sub>O<sub>5</sub> full cells\nachieve a high specific capacity of 124 mAh g<sup>–1</sup> while\ncycling for 600 h at 2 A g<sup>–1</sup>. These findings present\na low-cost electrolyte modification strategy for reversible zinc-ion\nbatteries.