Investigation focuses on resolving the temperature distribution of water within porous media of electrochemical device using ToF neutron imaging technique. The temperature of the water has a great impact on the performance of the device and the heat dissipation estimation is an important factor in electrochemical cell characterization in terms of voltage loss origins. This study aims to prove that it is possible to obtain temperature gradients and possibly the map of heat distribution over the active area of the cell to identify possible hot spots which can lead to accelerated degradation. Further work might lead to development of new diagnostic technique for Fuel Cells and Electrolyzers.