Investigating the Role of a Microporous Layer on the Water Transport and Performance of a PEMFC

Abstract

A test station was modified to collect water from the anode and cathode exhaust streams of a PEM fuel cell. Various combinations of cells were built and tested with (SGL10BA) and without microporous layers (SGL10BB) on the electrodes. Cells with a MPL at the cathode performed much better compared to cells with no MPL and the degradation rates were decreased. Water balance experiments were conducted with two combinations of inlet relative humidities (RH): 100% anode-60% cathode and 60% anode-100% cathode at current densities of 300, 500 and 700 mA/cm2. For the range of current densities studied, the net drag coefficient at 60{degree sign}C was -0.08-+0.08 mol H2O/mol H+ for RH 60% anode and 0.01-0.2 mol H2O/mol H+ for RH 100% anode. There was no significant change in the drag coefficient attributable to the presence of the MPL on the cathode. A MPL on the anode did affect the net water drag.