NOVEL AQUEOUS ALUMINUM SULFUR BATTERIES

Aluminum sulfur batteries based on concentrated polysulfide catholytes and an alkaline aluminum anode are introduced and investigated. The new battery is expressed by aluminum oxidation and aqueous sulfur reduction for an overall battery discharge consisting of 2Al + S4(2-) + 2 OH- + 4H2O --> 2Al(OH)3 + 4HS- E(cell) = 1.79V The theoretical energy density of the Al/S battery (based on potassium salts) is 647 Wh/kg. A first generation aluminum sulfur battery is demonstrated with an open-circuit voltage of 1.3 V, and energy densities based, respectively, on dry and total battery materials of 170 and 110 Wh/g.