Behaviour of Polymer Electrolyte Fuel Cells when Scaling Up from a Unit Cell to a Stack

摘要: Often the performance of a unit cell or a small stack of a few cells is used to extrapolate to the power and efficiency of a large stack. An important issue in scale-up is gas distribution to the individual cells in the stack. Due to the parallel gas supply, individual cells may not receive an optimal quantity of fuel or air. The stack may not deliver the maximum power predicted from the single cell measurement. Stoichiometric ratio {lambda}, gas pressure P, pressure difference {delta}P and flow field characteristics are the most important parameters for obtaining stable and similar voltage from each cell. (author)