A direct borohydride – acid peroxide fuel cell

Abstract

A fuel cell operating with aqueous sodium borohydride and hydrogen peroxide streams, with one, two and four cells (electrode area 64, 128 and 256 cm2) connected in a bipolar mode in a filterpress flow cell is reported. The oxidation of borohydride ion was carried out on Au/C particles supported on a carbon felt electrode while the reduction of hydrogen peroxide was carried out on carbon supported Pt on a carbon paper substrate. Comparable cell potentials and power densities to direct borohydride fuel cells reported in the literature were obtained. The challenges to further development includes: increasing the low current density and avoid decomposition of borohydride and peroxide ions. The maximum power obtained at 20oC for one, two and four cell stacks was 2.2, 3.2 and 9.6 W (34.4, 25 and 37.5 mW cm-2 respectively) with cell voltages of 1.06, 0.81 and 3.2 V at current densities of 32, 16 and 12 mA cm-2, respectively