Effect of Agar as Electrolyte Additive on the Aluminum-Air Batteries

The performance of aluminum-air battery is improved by adding agar molecules to the electrolyte (4 M NaOH). A significant suppression of the parasitic self-corrosion reaction and the improvement of fuel efficiency were obtained. The fuel efficiency is elevated up to 35.95% and the corrosion inhibition efficiency increases up to 62.8%. The physisorption of the agar molecules on the aluminum surface improved the performance of aluminum-air battery. The adsorption of agar molecules on the aluminum surface was observed from the surface analysis with SEM, Freundlich adsorption isotherm and the adsorption energies from the computational simulations. Furthermore, the optimized structure model of agar molecules on the aluminum surface was proposed. To figure out the inhibition performance of agar molecules as an electrolyte additive for aluminum-air batteries, the experimental methods such as hydrogen evolution test, electrochemical tests, surface analysis and density functional theory (DFT) with computational simulations are used in this study.