On the macroscale, fuel cell systems typically require heavy clamping constructions to seal layers. Here we report an alternative manufacturing approach that utilizes patterned polymer layers to yield much thinner, lighter laminar flow-based fuel cells (LFFCs). Most LFFCs reported to date have been proof-of-concept configurations. To meet the power requirements of portable electronic devices, challenges related to the design and manufacturing of scalable LFFC systems still need to be addressed. Here we report electrodes that are encapsulated between polymer layers with metallized polymer layers serving as current collectors. Assembly of a polymer-encapsulated anode and cathode yields a 1-mm thick all-polymer fuel cell, about one order of magnitude thinner than most microfluidic fuel cells. To identify performance changes associated with this alternative approach to electrode and catalyst integration, we first validated performance by analyzing the polymer-encapsulated anodes and cathodes individually, and then the complete cell after bonding the polymer-encapsulated electrodes together. This all-polymer fuel cell achieved a maximum power density of 10 mW cm(-2) at room temperature when using 1 M methanol as the fuel. Thin, lightweight fuel cell stacks for future portable power applications could be obtained by scaling and stacking of the all-polymer cell reported here. (C) 2013 Elsevier B.V. All rights reserved.