Lithium batteries store about 0.5 MJ/kg. Compared to the specific energy of burning lithium metal (40 MJ/kg) the energy from the electricity producing redox rea

Lithium batteries store about 0.5 MJ/kg. Compared to the specific energy of burning lithium metal (40 MJ/kg) the energy from the electricity producing redox reaction is pretty low. In the case of lithium batteries. Our problem isn't the stored electric energy, it's the medium being a highly flammable alkaline metal. If we could somehow store that 0.5 MJ/kg in a non-flammable medium with similar energy density it would have 5% the specific energy of a similarly massing piece of hardwood.