A novel gas distributor for fuel cells is proposed. It has three-dimensional current-collecting elements distributed in gas-delivery, fields- for effective current collection and heat/mass transfer enhancement. An analysis model has been developed in order to understand the performance of the output power density when the dimensions and distributive arrangement of the current collectors are different. Optimization analysts for a planar-type SOFC was conducted in order to outline the approach in optimizing a gas-delivery field when adopting three-dimensional current-collecting elements in a fuel cell. Experimental test of a proton exchange membrane (PEM) fuel cell adopting the novel gas distributor was conducted for verification of the new approach. Significant improvement of power output was obtained for the proposed new PEM fuel cells compared to the conventional ones under the same conditions except for the different gas distributors. Both the experimental ressults and modeling analysis are of great significance to the design of fuel cells of high power density.(C) 2004 Elsevier B.V. All rights reserved.