Abstract: Water transfer means (86) transfers fuel cell product water from a cathode water transport plate (34) to an anode water transport plate (23) of the same or a different fuel cell, wholly within a fuel cell stack (50), (disposed within each fuel cell of a fuel cell stack (50)). The water transfer means may be a very high permeability proton exchange membrane (21a), a water transfer band (90) such as silicon carbide particles, a porous water transfer zone (107), with or without a flow restrictor (109), internal water manifolds (112, 113) which extend through an entire fuel cell stack, or internal manifolds (112a, 112b, 112c, 112d, 113a, 113b, 113c, 113d) which extend only through groups of cells between solid plates (71).

Abstract: Water transfer means (86) transfers fuel cell product water from a cathode water transport plate (34) to an anode water transport plate (23) of the same or a different fuel cell, wholly within a fuel cell stack (50), (disposed within each fuel cell of a fuel cell stack (50)). The water transfer means may be a very high permeability proton exchange membrane (21a), a water transfer band (90) such as silicon carbide particles, a porous water transfer zone (107), with or without a flow restrictor (109), internal water manifolds (112, 113) which extend through an entire fuel cell stack, or internal manifolds (112a, 112b, 112c, 112d, 113a, 113b, 113c, 113d) which extend only through groups of cells between solid plates (71).

Abstract: A PEM fuel cell system (19) has a multifunction oxidant manifold (98) disposed contiguously beneath a fuel cell stack (20), serving as coolant accumulator (28). An electric heater (45) is powered by the fuel cell electrical output (47, 51) during frozen startup. Auxiliary pump (54) and conduits (55, 57, 58) forces water (28) above oxidant pressure in upper coolant manifold (41), into the oxidant flow fields to be warmed before flowing from the oxidant exhaust to the accumulator to melt additional ice. Alternatively, melted coolant is forced by oxidant pressure into coolant channels for heating. Conduit (61) conducts coolant from the coolant flow fields to the accumulator. A condensing heat exchanger (65) embedded in accumulator coolant receives oxidant exhaust. A condensing heat exchanger (70) has cold inlet air (75) and warm moist oxidant exhaust (72) on opposite sides, condensing liquid into the accumulator.

Abstract: A start system for enabling rapid fuel cell power from sub-freezing initial conditions in a fuel cell power plant which comprises heating an antifreeze coolant source and melting ice in the sump of a cell stack assembly with the heated antifreeze to effect start up.

Abstract: A start system for enabling rapid fuel cell power from sub-freezing initial conditions in a fuel cell power plant which comprises heating an antifreeze coolant source and melting ice in the sump of a cell stack assembly with the heated antifreeze to effect start up.

Abstract: The combination of a culturing process, bioluminescence mediated by luciferin/luciferase, and a light measuring device allows microbial monitoring in liquids with microbial concentrations as low as 1 CFU/100 ml. All characteristics of this monitor are zero gravity compatible which makes it particularly suitable for applications such as monitoring microbial counts in water in a zero gravity, closed environment.