Effects of carbon corrosion on proton exchange membrane fuel cell performance using two durability evaluation methods

A gas diffusion layer (GDL) is a major component that facilitates the discharge of generated water and the diffusion of reactant gases in the proton-exchange-membrane fuel cell (PEMFC). However, the GDL is composed of carbon materials, and therefore, it is vulnerable to carbon corrosion. When the PEMFC is at start-up or shutdown, a reduction reaction is induced where a temporary hydrogen shortage phenomenon occurs in the anode region caused by the air flowing into the gaps of the fuel cell stacks from the outside and from the oxygen crossover through the membrane. This phenomenon induces the reaction of carbon and water at the cathode, and eventually, carbon materials are corroded by an oxidation reaction. In this study, two durability evaluation methods for inducing carbon corrosion are applied to investigate the carbon corrosion phenomenon and performance degradation systematically. The effects of the corroded GDL and corroded membrane electrode assembly on the PEMFC performance are independently identified, and the causes of performance degradation of the corroded GDL are quantitatively investigated.