Study on a drasitically hydrogen consumption saving conditioning method for Polymer electrolyte membrane fuel cell

Abstract

In this study, a cost-effective fuel cell conditioning method is proposed to significantly shorten the processing time and reduce the consumption of hydrogen gas. This method, known as Air braking (AB) promotes triple-phase boundary (TPB) relocation by controlling air supply. Commonly used conditioning methods, including Constant Current (CC) and Constant Voltage (CV), are compared, and the results indicate that the limiting current densities of Air braking, Constant Voltage, and Constant current are 2.0616, 2.0072, and 1.9256 A/cm(2), respectively. Using Air braking, peak performance is achieved within 2 h, which is faster than that of Constant current and Constant Voltage at 4 and 21 h, respectively. Additionally, scanning electron micrograph (SEM) images of the membrane-electrode assembly (MEA) cross sections are captured after the Constant Current, Constant Voltage, and Air braking processes, and the thickness of the cross sections are measured. The cathode and anode catalyst layers are thickest when the Air braking method is used. This means that using Air braking conditioning activates the catalyst penetration into the membrane, expands the triple phase boundary, and consequently leads to performance improvement. According to our results, MEA conditioning with the Air braking method shortens the conditioning time significantly and achieves maximal MEA performance.