Understanding the Mechanisms for Recoverable Vs. Unrecoverable AEMFC Degradation

Abstract

In recent years there has been significant improvement in the achievable current and peak power densities [1 - 3] as well as the longevity of operating AEMFCs [4]. However, cell performance degradation remains an area of concern for the technology and a key to reducing performance decline is understanding mechanisms at work – which includes both recoverable and irrecoverable (irreversible) losses. To date, very few studies have been done that aim to understand and counter performance degradation mechanisms, while those that have generally focused only on irrecoverable performance degradation [5,6] The present study highlights recoverable (mainly associated with water management) and unrecoverable degradation mechanisms (AEM and Ionomer degradation, catalyst loss etc.) and propose solutions for these problems. Rigorous experiments have been performed to understand the degradation processes and fundamental factors have been explored responsible for AEMFC in-situ degradation.