Preparation of 3‐D Porous Pure Al Electrode for Al‐Air Battery Anode and Comparison of its Electrochemical Performance with a Smooth Surface Electrode

Abstract

Abstract This study compared the electrochemical performances of porous surface electrodes obtained by the salt casting process against a smooth surface electrode. Potentiodynamic polarization test, linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS) tests of porous and smooth Al electrodes were performed using 0.5 M NaOH solution. According to the Tafel analysis, the Jcor value of the Al‐porous electrode was measured as 3.23 mA cm−2, which is approximately 55 % higher than the Al‐smooth electrode. The Ecor value was more negative for the Al‐porous electrode. Results of the low charge transfer resistance (2.2 Ω) of the Al‐porous electrode compared to the Al‐smooth electrode (2.8 Ω) concluded that the porous surface was increased the current density by increasing charge transport due to higher surface area. The galvanostatic discharge tests of the electrodes were carried out in an Al‐air battery test cell using a graphite carbon air cathode. As a result, the power density of the Al‐porous electrode was approximately 42 % higher than the Al‐smooth surface electrode.

Keywords

• Al-air battery
• Anode electrode
• Electrochemical analyses
• Galvanostatic discharge
• 3-D porous Al