Experimental study on improving water management in proton exchange membrane fuel cells through intermittent forced hydrogen convection at the anode

• A supply method for intermittent forced hydrogen convection is proposed. • The hydrogen supply strategy is coupled with the purge strategy. • The voltage decay rate decreased by 41.56 % using this method. • Voltage stability over the duration of the purge was improved by 3.7 %. Proton exchange membrane fuel cells (PEMFCs) operating in the dead-end anode (DEA) mode are susceptible to flooding downstream of the channel, causing uneven water distribution and subsequent performance degradation. Therefore, this study introduces a novel bidirectional hydrogen supply and bidirectional purge (BHS-BP) mode. This mode requires only the addition of three solenoid valves and piping reconfiguration based on the DEA mode. This low-cost modification allowed any anode inlet or outlet to serve as a hydrogen supply or purge port, facilitating intermittent forced hydrogen convection by controlling the solenoid valves. This study tested both the proposed and DEA modes on an air-cooled open-cathode PEMFC stack. Results show that the proposed mode effectively enhanced water distribution uniformity, at 7A load current, when hydrogen is supplied downward along the channel for 6 s and upward for 12 s, the power enhancement reaches a maximum of 2.56 %. The average voltage decay rate for a single purge period is reduced from 0.947 mVs −1 to 0.913 mVs −1 , and the total voltage decay rate of the stack during long-time operation is significantly reduced from 0.243 mVs −1 to 0.142 mVs −1 , the Hydrogen utilization rate is increased by 1.259 %. Furthermore, the proposed mode improves the voltage output stability by 3.7 % during purge duration.