Enhancing the Efficiency of Open-Cathode PEM Fuel Cells: An Experimental Study

Abstract

Open-cathode Proton Exchange Membrane (PEM) fuel cells represent a promising clean energy technology for small-scale portable applications. These electrochemical devices convert hydrogen into electricity, producing water as the only byproduct. However, open-cathode PEM fuel cells face considerable challenges due to their dependence on ambient conditions, where fluctuations in air temperature and humidity directly impact efficiency. While several control strategies that optimize fuel cell performance have been described in the literature, a significant gap remains regarding the experimental implementation of Maximum Efficiency Point Tracking (MEPT) methods that integrate hydrogen waste reduction strategies. To address this limitation, this paper implements and validates a hybrid control strategy that combines Proportional-Integral (PI) and Perturb and Observe (P&O) controllers, identifying the optimal current setpoint and dynamically adjusting the hydrogen flow rate. The methodology involved characterizing fuel cells and systematically identifying maximum efficiency points (MEPs) which contributed to the development of the strategy. The proposed approach is experimentally validated using a 1kW PEM fuel cell system from Horizon, demonstrating an 39% reduction in hydrogen consumption compared to conventional control strategies. These efficiency improvements could substantially contribute to the adoption of open-cathode PEM technology in small-scale portable applications where fuel economy is a critical factor.