The characteristic of internal resistanceof PEMFC under dynamic loading

The component of internal resistance of proton exchange membrane fuel cell(PEMFC) has been analyzed in this paper.The characteristic of fuel cell under dynamic loading was discussed with on-site internal resistance.It was indicated that there was a stable internal resistance corresponding to a certain current density due to the water content of proton exchange membrane(PEM),the higher the current density was,the lower the internal resistance of fuel cell was.The concept of initial resistance Ri of fuel cell was defined.It was discovered that,during dynamic loading of PEMFC,the lower the initial resistance was,the lower the polarization degree was.The experiment results showed that the internal resistance kept decreasing when the fuel cell was flooding.It was pointed out that the real-time internal resistance could be used to diagnose the real-time conditions of PEMFC.