Discharge and corrosion behaviors of the alpha-Mg and beta-Li based Mg alloys for Mg-air batteries at different current densities

The discharge and corrosion behaviors of the wrought alpha-Mg and beta-Li based Mg alloys at large current densities were investigated in this work. The beta-Li phase strongly promotes the power density of Mg based anodes up to 58.9mW/cm(2) at 80 mA/cm(2), due to the dissolvable discharge product. The alpha-Mg based alloy suffers significant hydrogen gas evolution. The beta-Li phase memorably weakens the hydrogen evolution, due to prior dissolution of beta-Li phase. The discharged surface becomes fine and dense after the fast and uniform consumption of the anodes at large current density. The corroded phase transforminto particle-like clusters. Furthermore, the fine and dense precipitates play important roles in the spalling behavior of beta-Li phase and surface film formation process. The corrosion behaviors connecting discharge properties are also discussed in detail. (C) 2018 Elsevier Ltd.