HZB scientists have teamed up with partners of 3M Company in order to explore the water management in an alternative proton exchange membrane type, called PFIA. The experiments have been conducted using the infrared facilities of BESSY II synchrotron to reveal how water is retained even at dry conditions in PFIA. The observations explain why PFIA membranes are superior to the widely used NAFION membranes at higher temperatures and low humidity.