Dynamic internal performance of PEMFC under fuel starvation with high-resolution current mapping: An experimental study

• Published in: International journal of hydrogen energy Vol. 54; pp. 990 - 1000
• Main Authors: Ma, Ao, Yin, Cong, Yang, Haiyu, Yu, Jun, Huang, Kaixin, Qiao, Zemin, Tang, Hao
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 07.02.2024
• Subjects: Fuel starvation; Internal current distribution; Segmented fuel cell; Voltage reversal; Segmented fuel cell; Voltage reversal; Fuel starvation; Internal current distribution
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2023.11.191

The fuel starvation in a proton exchange membrane fuel cell (PEMFC) during automotive operation conditions could lead to severe decay of the catalyst layer and performance degradation. As the fuel starvation occurs locally and induces uneven reverse current inside the fuel cell stack, it is critical to understand the dynamic mechanism of the fuel cell internal performance during the fuel starvation process. In this work, a self-developed segmented cell with 396 segments is applied to measure the transient current distributions inside the fuel cell stack with active area of 406 cm2. In the present experiment, the fuel starvation process is simulated by decreasing the H2 stoichiometric ratio from 1.5 to 1.0 and the dynamic performance is tested as the cell voltage drops to the shutdown values. The results show that the current density uniformity worsens significantly during the fuel starvation, even though the load current is kept stable. With the cell voltage decreasing from 0.5 V to −0.9 V in fuel starvation, the maximum local current around H2 inlet rises from 1.363 A/cm2 to 3.697 A/cm2 and the lowest current density near H2 outlet drops from −0.039 A/cm2 to −0.1 A/cm2 under the load current density of 0.5 A/cm2. The analysis of transient local current behaviors corresponding to the voltage reversal process is beneficial to optimize the control of PEMFC system and mitigate the performance degradation. •Dynamic characteristics of voltage and current distribution during fuel starvation are studied.•A segmented fuel cell with 396 segments is applied to measure transient current distributions.•Maximum local current at H2 inlet rises significantly with decreased cell voltage in fuel starvation.•Uneven H2 distribution in fuel starvation worsens the uniformity of internal current distribution.