A design for a miniaturized (0.25 cm(2) active area) methanol/air polymer electrolyte fuel cell (PEFC) is described. The design incorporates all the basic parts of a large methanol/air PEFC in a smaller, simpler package. The electrodes for the mini-PEFC are constructed via standard microelectromechanical systems and microelectronic fabrication techniques using silicon substrates. Testing results show that the design successfully miniaturizes a large methanol/air PEFC and that such mini-PEFCs are able to perform to the levels of large cells in terms of current density.