Abstract: A reaction vessel that integrates and balances an endothermic process with at least one exothermic process of the fuel cell system. Preferably the exothermic process is conducted in stages to provide more uniform and/or controllable heat generation and exchange, and to produce a uniform and/or controllable temperature profile in the endothermic reaction process. The invention allows for the elimination of the working fluid loop of prior art systems that had unsatisfactory response times at startup, and during transient conditions, and also added to the overall mass and volume of the fuel cell system.

Abstract: A reaction vessel that integrates and balances an endothermic process with at least one exothermic process of the fuel cell system. Preferably the exothermic process is conducted in stages to provide more uniform and/or controllable heat generation and exchange, and to produce a uniform and/or controllable temperature profile in the endothermic reaction process. The invention allows for the elimination of the working fluid loop of prior art systems that had unsatisfactory response times at startup, and during transient conditions, and also added to the overall mass and volume of the fuel cell system.

Abstract: A device and method for operating a fuel cell system. The device includes a combustor that is configured to combine reactants used in the fuel cell in such a way as to produce an inert fluid used to inert electrodes within the fuel cell. The device also includes componentry to permit purging of the electrodes subsequent to their inerting. In one form, the combustor is of such thermal mass that heat generated by combustion of the reactants is substantially absorbed by the combustor such that recourse to supplemental cooling apparatus is not required. The combustor may also be configured to promote staged mixing and subsequent reaction of the fuel cell reactants to further limit excess heat generated by the reaction.

Abstract: A reaction vessel that integrates and balances an endothermic process with at least one exothermic process of the fuel cell system. Preferably the exothermic process is conducted in stages to provide more uniform and/or controllable heat generation and exchange, and to produce a uniform and/or controllable temperature profile in the endothermic reaction process. The invention allows for the elimination of the working fluid loop of prior art systems that had unsatisfactory response times at startup, and during transient conditions, and also added to the overall mass and volume of the fuel cell system.

Abstract: A fuel cell system having a dynamically controlled pressure regulator for varying the backpressure on the system under varying ambient temperatures and pressures.

Abstract: Method of operating an autothermal reformer (ATR) to produce a high temperature reformate including preheating steam and air inputs to the ATR with heat from the reformate. The steam is heated by the reformate, and the air is then heated by the steam. There is no direct heat exchange between the reformate and the air. In the heat exchangers effecting the heat transfer, the steam is kept at a higher pressure that both the reformate and the air.

Abstract: A fuel cell system having a methanol decomposition reactor that is used to solve cold startup and transient operating condition problems. Methanol is charged into a methanol decomposition reactor and heat is supplied to decompose methanol (an endothermic reaction) and to produce hydrogen molecules and carbon monoxide. Hot exhaust gas (effluent) from the methanol decomposition reactor is charged to a steam reformer to preheat the reformer. The hydrogen produced by methanol decomposition is used by a fuel cell stack.

Abstract: A fuel cell system having a thermally integrated isothermal CO-cleansing subsystem including a water-gas-shift reactor, a preferential oxidation reactor, at least one system heat exchanger, and a closed-loop heat transfer circuit dedicated to that subsystem. The heat transfer circuit utilizes a heat transfer medium which has a high specific heat and is circulated through the circuit at a sufficiently high rate as to thermally dominate the gas stream components communicating with the circuit.

Abstract: Method of operating an autothermal reformer (ATR) to produce a high temperature reformate including preheating steam and air inputs to the ATR with heat from the reformate. The steam is heated by the reformate, and the air is then heated by the steam. There is no direct heat exchange between the reformate and the air. In the heat exchangers effecting the heat transfer, the steam is kept at a higher pressure that both the reformate and the air.

Abstract: An electrochemical engine for a vehicle comprises a fuel processor operating to process liquid fuel to hydrogen gas reformate, a combustor to generate heat for the fuel processor, and a fuel cell stack to generate electricity from the hydrogen gas reformate and producing water vapor by-product. A water management system of the engine comprises a condenser to reclaim liquid water from the water vapor by-product and a water tank for storing the reclaimed water. A water pump circulates water from the water tank to the fuel processor. A drainage valve is operable to open to release water from the water tank to a freeze tank to avoid freezing water in the water tank.

Abstract: A thermally integrated two-stage methanol reformer including a heat exchanger and first and second reactors colocated in a common housing in which a gaseous heat transfer medium circulates to carry heat from the heat exchanger into the reactors. The heat transfer medium comprises principally hydrogen, carbon dioxide, methanol vapor and water vapor formed in a first stage reforming reaction. A small portion of the circulating heat transfer medium is drawn off and reacted in a second stage reforming reaction which substantially completes the reaction of the methanol and water remaining in the drawn-off portion. Preferably, a PrOx reactor will be included in the housing upstream of the heat exchanger to supplement the heat provided by the heat exchanger.

Abstract: A fuel cell system including a fuel reformer heated by a catalytic combustor fired by anode and cathode effluents. The combustor includes a turbulator section at its input end for intimately mixing the anode and cathode effluents before they contact the combustors primary catalyst bed. The turbulator comprises at least one porous bed of mixing media that provides a tortuous path therethrough for creating turbulent flow and intimate mixing of the anode and cathode effluents therein.

Abstract: A multi-stage, isothermal, carbon monoxide preferential oxidation (PrOx) reactor comprising a plurality of serially arranged, catalyzed heat exchangers, each separated from the next by a mixing chamber for homogenizing the gases exiting one heat exchanger and entering the next. In a preferred embodiment, at least some of the air used in the PrOx reaction is injected directly into the mixing chamber between the catalyzed heat exchangers.

Abstract: A fuel cell system including a fuel reformer heated by a catalytic combustor fired by anode effluent and/or fuel from a liquid fuel supply providing fuel for the fuel cell. The combustor includes a vaporizer section heated by the combustor exhaust gases for vaporizing the fuel before feeding it into the combustor. Cathode effluent is used as the principle oxidant for the combustor.