TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The first and second gas-diffusion backings comprise porous electrically conductive material, fibrous carbon structure and/or particulate carbon.    TECHNOLOGY FOCUS - TEXTILES AND PAPER - Preferred Materials: The fibrous carbon structure is paper, woven fabric, or non-woven web.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The electrically conductive material comprises porous component, preferably carbon particles and/or polymeric component such as fluoropolymer. The electrocatalyst coating composition comprises electrocatalyst, and ion-exchange polymer such as highly fluorinated ion-exchange polymer comprising sulfonate ion exchange groups. The polymer membrane is highly fluorinated ion-exchange polymer comprising sulfonate ion exchange groups or a reinforced perfluorinated ion-exchange polymer membrane. The thermoplastic polymer is melt-processable fluoropolymer, partially fluorinated polymer, thermoplastic fluoroelastomer, aromatic condensation polymer, polyolefin, modified polyolefin, thermoplastic elastomer, liquid-crystal polymer, and/or aromatic polyamide, preferably polyvinylidene fluoride, polyaryl ether ketone, or polyethylene.    TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Process: The first and second electrocatalyst coating compositions are applied to opposite sides of polymer membrane to form a catalyst coated membrane prior to formation of multi-layer sandwich. The coating compositions are applied by screen printing, offset printing, gravure printing, flexographic printing, pad printing, slot die coating, doctor blade coating, dip coating, or spray coating. Application of thermoplastic polymer is by injection or compression molding. The peripheral edge of polymer membrane is supported by structural features in the tool to assist polymer in flowing onto both sides. The molding tool is provided with low thermal conductivity inserts in part of the area where it does not contact the thermoplastic polymer. A portion of tool surface within the mold cavity has rough texture or spikes. The edge of the membrane is treated to improve wettability or adhesion to thermoplastic polymer. A fountain-flow pattern of inflowing polymer increases the separation between first and second gas-diffusion backings, and/or first and second electrocatalyst coatings.Preferred Dimensions: The peripheral area of the tool is thicker than the area where multi-layer element is supported. The polymer membrane and gas-diffusion backings have the same or different size.