Kinetics of the Chemical Dissolution of Vanadium Pentoxide in Acidic Bromide Solutions

A novel vanadium bromide redox flow battery employing a vanadium bromide electrolyte in both half-cells has been proposed. Preparation of the electrolyte for this redox cell requires the chemical dissolution of vanadium pentoxide powder in the acidic bromide supporting electrolyte. In this study, the kinetics of the chemical dissolution process were investigated and a second order surface controlled reaction is reported with rate equation given by: Rate = 5 × 10−4(l mol−1 s−1)[Br−]2 at 25 °C and an activation energy of 37.2 kJ mol−1.