Non-destructive platinum catalyst-replenishment method for deteriorated polymer electrolyte membrane fuel cells

Abstract

A novel method for replenishing platinum catalysts on an electrolyte membrane of polymer electrolyte membrane fuel cell (PEMFC) is studied. The method injects electrocatalyst-supplementing ink into a pre-assembled fuel cell in a simple and non-destructive manner. For replenishing, straightforward catalyst-replenishment equipment and corresponding protocol are proposed. The protocol consists of injection, penetration, and purge processes. As a feasibility study, the method is performed on fuel cells with pristine membranes. Target fuel cells for this study include a membrane-assembled cell without catalyst layers (CLs) (Cell 1) and a cell assembled with a membrane-coated cathodic CL (Cell 2). An open-circuit voltage of 0.804 V in Cell 1 and a current of 77 mA in Cell 2 are measured, as supported through electrochemical impedance spectroscopy. Results of energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy also support the presence of platinum catalysts.