Effects of external field treatment on the electrochemical behaviors and discharge performance of AZ80 anodes for Mg-air batteries. (1st February 2020)

• Record Type: Journal Article
• Authors: Chen, Xingrui; Ning, Shaochen; Le, Qichi; Wang, Henan; Zou, Qi; Guo, Ruizhen; Hou, Jian; Jia, Yonghui; Atrens, Andrej; Yu, Fuxiao
• Is Part Of: Journal of materials science & technology. Volume 38(2020)
• Page Start: 47
• Page End: 55
• Publication Date: 2020-02-01
• Subjects: Mg-air batteries -- Magnesium alloy -- Discharge performance -- Electrochemical behaviors -- Ultrasonic field -- Electromagnetic field; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2019.07.043
• Languages: English
• ISSNs: 1005-0302

Abstract

Abstract: In this work, the effects of external field treatment on electrochemical behaviors and discharge performance of as-cast Mg-8%Al-0.5%Zn (wt%) anodes for Mg-air batteries are systematically investigated in 3.5 wt% NaCl solution. The external field treatment particularly the variable-frequency ultrasonic field can dramatically refine the α-Mg grains and β phases. The grain size decreases from 1594.8 ± 43 μm (untreated billet) to 140.6 ± 15 μm after variable-frequency ultrasonic field treatment. The values of open circuit potential, electrochemical activity and corrosion resistance of Mg-8%Al-0.5%Zn anode are improved with external field treatment, which should be attributed to refined grains and dispersive β phase. The external field treatment especially the variable-frequency ultrasonic field improves stability and the value of cell voltage, and enhances the discharge performance of the Mg-8%Al-0.5%Zn anode. The variable-frequency ultrasonic field treated anode has the best discharge capacity and anodic efficiency at current density of 45 mA cm −2, with the values of 1417 mA h g −1 and 63.3%, respectively. The ultrasonic field vibration changes the dissolution behavior of α-Mg matrix during the discharge process, showing the oriented surface morphologies.