Synergistic regulating the aluminum corrosion by ellagic acid and sodium stannate hybrid additives for advanced aluminum-air battery

Aqueous aluminum-air batteries have attracted tremendous interest because of their inherent safety and low cost. However, their lifespan is limited by the severe self-corrosion at aluminum anode. Herein, a design strategy is presented to suppress the corrosion by modifying the aluminum/electrolyte interface. Adding hybrid additives (ellagic acid and sodium stannate) can significantly reduce the corrosion rate of aluminum anode (0.7667 mg cm−2 min−1 in the blank electrolyte and 0.3662 mg cm−2 min−1 in the electrolyte with hybrid additives). The aluminum-air full battery can achieve a higher discharge specific capacity of 2439 mAh g−1. Spectral characterization and theoretical calculation confirm that the corrosion inhibition is attributed to a composite protective film formed on the aluminum surface. This strategy has proven to be general in preventing metal corrosion.