Research on uniformity of vanadium redox-flow battery

The uniformity of the vanadium redox flow battery (VRB) directly affect its life span. The flow channel structure and the operating parameters of the battery had been measured and analyzed. By optimizing the pipeline structure and flow frame structure, the uniformity of the stack was improved. When the ratio of executive diameter to branch pipe diameter was reduced from 4:3 to 4:1, the standard deviation of the liquid flow velocity was reduced from the 0.039 m/s to 0.001 m/s. The standard deviation of the stack liquid flow had been decreased from the 0.142 m/s to 0.032 m/s by optimizing the flow frame structure. The standard deviation of VRB increased linearly with the increase of the current. The slope and intercept of the linear equation related to the properties of electrolyte, electrode materia, and surface structure. The standard deviation of VRB decreased with the increase of the flow rate, but stayed the same after a certain flow was reached. The experimental results can provide technical support for the material selection and the operation of VRB. © 2017, Chemical Industry Press. All right reserved.