Novel aluminum batteries: a step towards derivation of superbatteries

In alkaline-elevated temperature electrolytes, planar aluminum is capable of supporting current densities one to two orders of magnitude higher than conventional electrodes. Conditions are investigated in which these unusually high power densities, through the electrolyte-surface interface, may also occur with high coulombic efficiency, a step towards the derivation of superbatteries. Aluminum-ferricyanide batteries based on aqueous solution phase alkaline ferricyanide cathodes and solid aluminum anodes are investigated. The battery is expressed by aluminum oxidation and ferricyanide reduction for an overall battery discharge consisting of: Al + 3OH(-) + 3Fe(CN)(6)(3-)-->Al(OH)(3) + 3Fe(CN)(6)(4-); E-cell =2.8 V. Aluminum potassium ferricyanide batteries are demonstrated with current densities approaching 2000 mA/cm(2) with polarization losses of 0.6 mV/cm(2)/mA, resulting in a high power density of over 2 W/cm(2). (C) 1998 Elsevier Science B.V.