Anhydrous Proton Exchange Membranes for High-Temperature Hydrogen Fuel Cells

A key component of hydrogen fuel cells is the proton exchange membrane (PEM), which facilitates the movement of protons from the anode to the cathode. Current PEMs rely on water and acidic conditions, limiting the operating temperature to 80 °C, while hydrogen fuel cells perform best at 150-180 °C.

This research aims to develop a dry and thermally stable PEM from linear and branched fluoroaromatic polymers with imidazole groups for proton conduction, allowing the PEM to perform at higher temperatures without flooding. The structure and thermal stability of the polymers are characterized using Nuclear Magnetic Resonance, Gel Permeation Chromatography, Differential Scanning Calorimetry, and Thermal Gravimetric Analysis. Synthesis modifications are ongoing to improve thermal performance.

A locally assembled Electrochemical Impedance Analyzer (–100 to 200 °C, 10 µHz to 2 MHz), validated with lab-made and standard membranes, alongside a Dynamic Mechanical Analyzer, will assess electrical and mechanical properties. We will present structural, thermal, conduction, and mechanical data for membranes with varying branching and imidazole content, outlining preliminary structure–property relationships and strategies to enhance stability for high-temperature PEM applications.