Abstract: An electrochemical cell assembly includes first and second flow field plates, first and second gas diffusion media disposed between the first and second flow field plates, and a membrane electrode assembly disposed between the first and second gas diffusion media. The membrane electrode assembly can include a proton exchange membrane, and a catalyst layer on the proton exchange membrane. The catalyst layout can be configured to omit the catalyst layer from a portion of the proton exchange membrane adjacent an edge region of one of the first and second gas diffusion media, thereby enabling at least a portion of the reactant fluid flow to first encounter a region of the membrane electrode assembly without the catalyst layer. The modified catalyst layout can improve reactant fluid flow along the membrane electrode assembly, reduce wear on the membrane electrode assembly and improve electrochemical cell efficiency during operation.

Abstract: A sealing and repair technique is provided for forming complex and multiple seal configurations for fuel cells and other electrochemical cells. To provide a seal, for sealing chambers for oxidant, fuel and/or coolant, a groove network is provided extending through the various elements of the fuel cell assembly. A source of seal material is then connected to an external filling port and injected into the groove network, and the seal material is then cured to form the seal. There is thus formed a “seal in place”, that is robust and can accommodate variations in tolerances and dimensions, and that can be bonded, where possible, to individual elements of the fuel cell assembly. To repair part of an electrochemical cell stack, some elements are removed and either repaired or replaced. The cell assembly is then put together again and a bore is provided for injection of fresh seal material.

Abstract: A membrane electrode assembly for an electrochemical cell assembly is provided with a modified catalyst layout. The modified catalyst layout improves reactant fluid flow along the membrane electrode assembly, reduces wear on the membrane electrode assembly and improves electrochemical cell efficiency during operation.

Abstract: An electrochemical cell assembly with structural improvements for improving cell operation. The electrochemical cell assembly may include at least one of an extended MEA and chamfered edges on the flow field plates for preventing the shorting of the anode and cathode flow field plates. Further, the flow field plates may include a pocket for providing an appropriate space to accommodate a gas diffusion media and applying an appropriate amount of compression to the gas diffusion media.

Abstract: A sealing technique is provided for forming complex and multiple seal configurations for fuel cells and other electrochemical cells. To provide a seal, for sealing chambers for oxidant, fuel and/or coolant, a groove network is provided extending through the various elements of the fuel cell assembly and a seal material is then injected into the groove network. Several structural improvements have been made to cell components in relation to this seal in place process to reduce manufacturing cost and improve the performance of the electrochemical cells.