Effective Testing Matrix for Studying Membrane Durability in PEM Fuel Cells: Part 2. Mechanical Durability and Combined Mechanical and Chemical Durability

Abstract

Accelerated testing that targets specific mechanisms of chemical and mechanical durability, and tests that target both failure mechanisms at the same time can be an effective tools to advance membrane technologies for PEM fuel cells. Such tests should be accelerated to reduce development times, with conditions relevant to the given application. In studies of membrane mechanical durability, uniform membrane degradation was obtained by using careful test design. When conducting a combined mechanism accelerated test, the relative balance of the two mechanisms should be considered. Too much mechanical stress in the test can overwhelm improvements in the chemical durability of the materials and vise versa. Customer screening and more realistic testing conditions are used to verify accelerated test conclusions. Test results indicate that combinations of these test protocols enable the dependable selection of more mechanically and chemically durable membranes and also provide quantitative data to assist understanding of degradation mechanisms in fuel cells under various operation conditions.