High power density Al-air batteries with commercial three-dimensional aluminum foam anode

Aluminum (Al) is the desired material for metal-air batteries, owing to its attractive electrochemical performance. Unfortunately, the actual power densities of the batteries are relatively low. This research describes a high power density Al-air battery equipped with commercial three-dimensional (3D) Al foam as the anode coupled with dual cathodes in NaOH electrolyte. The corrosion responses and electrochemical performances of the 3D Al foam are investigated in 1, 2, and 4 mol L −1 NaOH solutions. Compared with the dense Al plate, the Al foam owns better electrochemical performances in 4 mol L −1 NaOH solution. The peak power density of the Al foam (80.6 mW cm −2 ) increases by ~ 56.84%, relative to the Al plate (51.2 mW cm −2 ). At 100 mA cm −2 , the capacity density of Al foam reaches 1983 mAh g −1 , and the energy density comes to 1567 Wh Kg −1 . Considering the cost and performance, the commercial 3D Al foam anode with a large specific surface and small electrode polarization is expected to be a promising anode material for the Al-air batteries.