An artificial coating of the Anode may revive an old battery chemistry. http://www.batterypoweronline.com/news/nrel-research-overcomes-major-technical-obstacles-in-magnesium-metal-batteries/ Advantages: Magnesium is cheaper and more plentiful than Lithium Magnesium gives up 2 electrons vs 1 for Lithium, so has the potential for double the energy density