In this paper, a measurement cell for recording synchrotron X-ray images of low and high temperature PEM fuel cells is described. The experimental setup allows for recording of cross-sectional images, as well as for radiograms in through-plane direction, with limited signal degradation. First results on H(3)PO(4) concentration and distribution as a function of the operating conditions are presented. This basic cell design is optimized for liquid water detection. To visualize water in an operating cell the energy of the synchrotron X-ray beam has been chosen in a range between 7 and 30 keV where high resolution images can be obtained. The cell design is described in detail, and references to results obtained with LT-PEMFC applications focusing on liquid water evolution are given. For HT-PEMFC applications, the method of synchrotron X-ray imaging can provide an insight on electrolyte concentration and distribution. These investigations show that significant information can be collected on electrolyte distribution and concentration as a function of operating parameters such as temperature, media utilization and humidification degree. First results for the dependence of electrolyte distribution on operating conditions are presented. (C) 2010 Elsevier B.V. All rights reserved.