The Br2/H2\ redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and (-) electrode architecture are investigated. Increasing hydrogen pressure and depositing the (-) catalyst layer on the membrane instead of on the carbon paper backing layers have a large positive impact on performance, enabling a limiting current density above 2\ A cm-2\ and a peak power density of 1.4\ W\ cm-2. Maximum energy efficiency of 79\% is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br-\ reversibly adsorbs at the Pt (-) electrode for potentials exceeding a critical value, and the extent of Br-\ coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.
}, year = {2015}, booktitle = {Journal of Applied Electrochemistry}, journal = {Journal of Applied Electrochemistry}, series = {Journal of Applied Electrochemistry}, volume = {45}, pages = {11 - 19}, month = {01/2015}, issn = {0021-891X}, doi = {10.1007/s10800-014-0772-1}, }