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 cm 2 ) 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 20• C 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.

A Self-Supported Direct Borohydride-Hydrogen Peroxide Fuel Cell System

“…However, there are several technical challenges that need to be addressed in the DBFCs employing air or H 2 O 2 as oxidant [7][8]. Among these, DBFCs with acidified H 2 O 2 as oxidant provide high operating voltages and power densities, and are especially useful for submersible and space applications where anaerobic conditions prevail [8][9][10][11].…”

The filter-press FM01-LC laboratory flow reactor and its applications

“…A number of redox couples have been proposed for use within large-scale flow batteries. Operational technologies include bromine/polysulfide, all vanadium, zinc/bromine, zinc/cerium [15,71], borohydride [13] and soluble lead-acid [14,72]. The need to scale-up this type of battery (power capacity and current density is proportional to electrochemical cell size), lead to the use of a flexible, controlled flow cell.…”

“…Ponce de León et al [14] evaluated a sodium borohydridehydrogen peroxide liquid electrolyte fuel cell on a bench scale using the FM01-LC reactor. The electrode reactions are:…”

“…The authors reported a peak power density of 50 mW cm À2 using a six-cell fuel cell stack which is 30% higher than the power density obtained with the FM01 (35 mA cm À2 ) cell described above. It should be realised that the concentration of hydrogen peroxide in the work reported by Raman et al [73] was 2 mol dm À3 [73] whereas in the work reported by Ponce de Leon at al., it was 1 mol dm À3 [14].…”

“…Following a description of electrodes and cells, the importance of reaction environment is considered. A general review of the versatility and uses of the filter-press-type FM01-LC electrolyser in applications including electrosynthesis [8,9], metal ion removal [10,11], electrochemical degradation of organic contaminants [12,12] and energy storage [14][15][16] is then presented.…”