Effect of Annealing Process on Anode Discharge Performance of Aluminum-Air Batteries

This paper investigates the effect of annealing process on the discharge performance of aluminum air battery anode, the results show that. The annealing treatment after rolling can make the grain of aluminum anode be refined, and the surface of aluminum anode with lower morphology has Bi and Pb precipitation, resulting in pitting corrosion. With the increase of morphology, the element distribution is uniform, and the precipitated phase is dissolved in the aluminum matrix, and the corrosion performance is improved. At the same time, the fine grain reduces the internal potential difference of aluminum anode and improves the corrosion resistance of the anode. The microstructure of aluminum anode with large morphology variable becomes more uniform after annealing, which improves the corrosion resistance of aluminum anode. Compared with the aluminum anode with low morphology, the energy density and specific capacity of the anode with high morphology were increased by 584.35 Wh·kg⁻¹ and 579.61 mAh·g⁻¹, respectively, and the anode efficiency was also increased by 19.45%. The anode efficiency of the high-variant sample was increased by up to 10.74% after annealing. The fine-crystalline aluminum anode exhibited higher discharge voltage and electrochemical performance than the coarse-crystalline aluminum anode at constant current density.