(GR8) Design of a Molten Salt Metal-Air Battery with High-Energy Density

Authors: Amanda Lota, Nicolas Masse, Mahya Shahabi, Lucien Wallace

Advisors: Adam Powell

Category: Graduate


Decarbonization of long-haul transportation i.e. ships and trains is among the toughest challenges toward eliminating greenhouse emissions, but metal-air batteries have extraordinary potential to meet this challenge. This talk will present experimental and modeling results for a novel molten salt magnesium-air battery with a MgCl‚-NaCl-KCl-MgO electrolyte operating at 420-620°C. O² dissolves at the cathodes and Mg² at solid magnesium anodes. Experimental results show 1.9 V open circuit voltage, which is the highest to date for an Mg-air battery. Modeling shows up to 0.5 W/cm² at 80% efficiency or 3.3 W/cm² at 42% efficiency. Directional solidification removes MgO reaction product from the molten salt electrolyte. The stability of the cathode material is another criterion for this fuel cell. This battery has the potential for 30-40 times the energy of lithium-ion batteries at very high efficiency, and its Mg anode and molten salt materials are abundant in seawater.