Investigation of the sensitivity of operating temperature for water distribution of fuel cell stack based on electrochemical impedance spectroscopy

The water content of fuel cell can be controlled by adjusting working conditions. Although the water content cannot be directly observed, the electrochemical impedance spectroscopy (EIS) data can be used to characterise the internal water content. In this paper, the EIS data of fuel cell are obtained through experiments. According to the results, changing the operating temperature has a significant impact on the low-frequency impedance. The temperature should be changed to avoid dehydration or flooding at different current density. The impedance of single cell shows that although the optimised temperature improves performance, there is still an imbalance of water content among the cells. This article also compares the effect of controlling relative humidity and working temperature. The comparison shows that the two solutions have close effects on the impedance. Considering various factors, controlling working temperature is an effective method of fuel cell water management. © 2022 Inderscience Enterprises Ltd.