Impedance Spectroscopy to Prevent Performance Degradation due to Sea Salt for Marine Polymer Electrolyte Fuel Cells

Abstract

The application of polymer electrolyte fuel cells (PEFCs) for marine vessels will be an effective means of reducing the environmental impact and solving energy crisis problems. The diagnosis of abnormal operational conditions is an important aspect of improving the reliability and durability of marine PEFCs, and helps to ensure long-term safe and stable operation. Electrochemical impedance spectroscopy (EIS) is a technique suitable for the real-time diagnosis of operational PEFCs. EIS analyses are performed using an equivalent circuit model consisting of several resistances and capacitances, associated with ohmic, activation and concentration overpotentials. The present work investigates the effects of abnormal variations in the cell temperature as well as the flow rate and relative humidity values of supplied gases on the cell resistance and capacitance values using EIS analysis. The detection of sea salt (NaCl) contamination in the cathode air stream is also evaluated by injecting a NaCl solution into the cathode inlet gas.