Effect of Tween 85 and calcium malate as hybrid inhibitors on the performance of alkaline aluminum-air batteries

The great potential application of aluminum-air (Al-air) batteries is due to their high safety and energy density. The downside is the severe self-corrosion of the Al anode. Herein, a novel additive package consisting of tween 85 (T-85) and calcium malate (CM) is developed to inhibit the hydrogen evolution of the self-corrosion of Al anode in alkaline Al-air batteries. In alkaline solutions, Ca2+ in CM preferentially forms Ca(OH)2 precipitates. It can adhere to the surface of Al alloy providing additional binding sites for [C4H4O5]2- adsorption at the solution/ Al alloy interface. In addition, T-85 can also form a hydrophobic layer from its carbon chains. Al malate can be filled into the hydrophobic layer to form a bifunctional film on the anode. The utilization rate of the anode can reach 57.16 % and the efficiency of the corrosion inhibition can reach 76.23 %. This work provides a new reference for developing the full Al-air battery unit.