Development of 130 kW Self-Humidifying Proton Exchange Membrane Fuel Cell System

Replacing external humidifiers with self-humidification technology can simplify the structure of fuel cell systems and improve their cost-effectiveness. This paper analyzes a feasible method for achieving self-humidification at the system level, suggesting that membrane drying can be prevented by increasing the hydrogen circulation pump revolutions, reducing the air stoichiometric ratio, and controlling the stack temperature. A theoretical design for each subsystem of the 130 kW PEMFC-based self-humidifying fuel cell system was also proposed. The system was built and tested under steady-state conditions, achieving an efficiency of 86.7% under the rated power. Additionally, the stack's high-frequency resistance, voltage, and cathode/anode pressure drop were measured to analyze the water content status inside. The results indicate that the high-frequency resistance of the stack was 57.17 mΩ·cm2, and the single-cell voltage difference was 0.03 V, which means no membrane drying failure occurred under the rated power. The construction of the 130 kW self-humidifying fuel cell system described in this paper provides guidance for designing and integrating self-humidification systems based on PEMFC.