Visualization of flow patterns in a cell of redox flow battery by infrared thermography

摘要

For redox flow batteries (RFBs), it is very important to flow electrolyte uniformly in the porous electrodes. Integrated segment methods have been studied to analyze in situ flow behavior in a cell of RFBs. However, the resolution of the contour plots obtained with these methods is very low at present since only several dozen segments can be used. Therefore, to visualize the flow patterns of electrolyte in the electrode, a model cell which consists of a single porous electrode and two clamping plates was constructed and tested. The experiments were performed by feeding hot working liquid to the cell after cooling the cell without discharging cooling water, and measuring the temperatures in the electrode by thermocouples and the temperature distribution of the outer surface of the clamping plate by infrared thermography (IRT). Time variations of temperatures of the outer surface of the clamping plate show similar trends with one in the electrode. Further, the temperature distributions measured by IRT were considerably changed when the inlet and outlet conditions were changed. This shows that the flow patterns of electrolyte in the electrode can be visualized by measuring the outer surface temperature distribution of the clamping plate by IRT.