Experimental investigation on the impact of hydrogen supply temperature on fuel cell stack performance

To enhance the hydrogen utilization rate, hydrogen recirculation devices are frequently adopted in high-power fuel cell systems to reclaim the residual hydrogen in the exhaust gas. Nevertheless, this brings about a more adverse water-vapor environment for the operation of proton exchange membrane fuel cell (PEMFC). In this paper, an 80kW PEMFC stack was independently designed and a control variable approach was employed to explore the influence of the inlet hydrogen temperature on the performance of the PEMFC stack. The results demonstrate that a significant end effect exists in high-power PEMFC stacks, with the lowest voltage emerging at the single cell on the hydrogen inlet side, where the performance of the single cell cannot operate stably due to the excessively low hydrogen temperature. Additionally, the study revealed that 49°C is the turning point of the inlet hydrogen temperature. When the hydrogen temperature is lower than 49°C, the voltage of the PEMFC stack decreases significantly as the temperature drops. Conversely, when the hydrogen temperature is higher than 49°C, the PEMFC stack can operate stably. This research holds crucial theoretical and practical significance for enhancing the performance and service life of high-power fuel cells.