Magnetic Resonance Imaging and Tunable Diode Laser Absorption Spectroscopy for In-Situ Water Diagnostics in Polymer Electrolyte Membrane Fuel Cells

Abstract

Magnetic resonance imaging (MRI) and tunable diode laser absorption spectroscopy (TDLAS) are focused as novel diagnostic techniques for in-situ measurement of water in operating polymer electrolyte membrane fuel cells (PEMFCs). Basic principle and practical applications of MRI to visualize water content distribution in polymer electrolyte membranes (PEMs) are described. It is shown that MRI visualization gives us fundamental understandings on water transport processes involved in PEMFCs. In-situ TDLAS measurement technique is also presented as a diagnostic tool to evaluate variation of water vapor concentration in gas flow channels in PEMFCs. TDLAS measurement in combination with numerical analysis can be used to obtain local current density distribution and local water transfer numbers across the membrane. Recent advances and future prospects on MRI and TDLAS as in-situ diagnostic technique for water transport in operational PEMFCs are summarized.