(215b) Comparison between Pemfc Water Management Model and in-Situ Water Transfer Measurements

This work describes the design steps and demonstrates the capabilities of a novel water transfer factor measurement apparatus for the purpose of experimental analysis, water management model validation and tailoring. Several measurement concepts were screened on the basis of their water transfer factor accuracy using a Monte-Carlo approach. The most promising concept was assembled and tested to assess its actual measurement accuracy. Combining cathode and anode measurements, the simulated water transfer factor accuracy was typically better than ±0.01. The measurement strategy was finally implemented on a real PEMFC and several series of tests were conducted. Experimental data was in good agreement with a recently proposed model under moderately high pressure (200 kPa) and current densities (above 0.3 A/cm²), but indicates that the model tends to underestimate the back diffusion of the water from the cathode to the anode especially at low current densities.