Researchers demonstrate AZ31 magnesium alloy foils as thin anodes for rechargeable magnesium batteries
10 August 2021
Researchers in Israel and Spain have demonstrated the feasibility of processing ultrathin Mg anodes for use in rechargeable magnesium battery cells by using AZ31 Mg alloys (3% Al; 1% Zn). A paper on their work appears in the journal ChemSusChem.
Rechargeable magnesium batteries are of interest because of their potential high energy density, and reduced environmental impact and greater stability compared to lithium-ion batteries. However, a critical challenge for devoloping RMBs is finding suitable electrolyte solutions that enable efficient and reversible Mg operation.
Most studies on magnesium batteries have concentrated on novel electrolyte systems; only few studies have focused on the practical feasibility of using pure metallic Mg as the anode material. Pure Mg metal anodes have been demonstrated to be useful in studying the fundamentals of nonaqueous Mg electrochemistry. However, the researchers noted, pure Mg metal may not be suitable for mass production of ultrathin foils (< 100 microns) due to its limited ductility.
The metals industry overcomes this problem by using ductile Mg alloys.
The researchers found that their AZ31 thin-film alloys presented reversible Mg dissolution and deposition behavior in complex ethereal Mg electrolytes solutions comparable to that of pure Mg foils.
Optical images of the AZ31 foil during the rolling process. Maddegalla et al.
They also demonstrated that secondary Mg battery prototypes comprising ultrathin AZ31 Mg alloy anodes (≈ 25 µm thick) and Mg x Mo 6 S 8 Chevrel phase cathodes exhibit cycling performance that is equal to that of similar cells containing thicker pure Mg foil anodes.
The possibility of using of ultrathin processable Mg metal anodes is an important step in the realization of rechargeable Mg batteries.—Maddegalla
Maddegalla, A., Mukherjee, A., Blázquez, J.A., Azaceta, E., Leonet, O., Mainar, A.R., Kovalevsky, A., Sharon, D., Martin, J., Sotta, D., Ein-Eli, Y., Aurbach, D. and Noked, M. (2021), “AZ31 Magnesium Alloy foils as thin Anodes for Rechargeable Magnesium Batteries.” ChemSusChem. doi: 10.1002/cssc.202101323
Partha Saha, Moni Kanchan Datta, Oleg I. Velikokhatnyi, Ayyakkannu Manivannan, David Alman, Prashant N. Kumta (2014) “Rechargeable magnesium battery: Current status and key challenges for the future,” Progress in Materials Science, Volume 66, Pages 1-86, doi: 10.1016/j.pmatsci.2014.04.001