Water management in fuel cells - a challenge for non-desctructive high resolution methods

Water management in fuel cells - a challenge for non-desctructive high resolution methods. An efficient water management is a key issue in the development of fuel cells with regard on long term stability and performance. The porous gas diffusion layer is employed to ensure a uniform distribution of the reactant gases across the electrochemically active area, the catalyst layer. In this contribution the joined research activities of the Helmholtz Center Berlin (visualization) and the Center for Solar Energy and Hydrogen Research (ZSW, fuel cell development) are presented, where the evolution, distribution as well as the transport of liquid water in fuel cells under operating conditions is investigated. By means of synchrotron radiography and tomography small water cluster in the range of several nano-liters are detected. Based on these findings an empirical selection of materials can be avoided and new materials can be tailor-made to fulfill the engineering requirements.