Patent ID: 9525183
Filing Date: 2016-12-20
CPC Classification: H01M,Y02E

Claim Text:
1. A fuel cell system comprising: a first fuel supply means for supplying a hydrocarbon containing fuel, an oxidant supply means for supplying oxidant, an exothermally operating partial oxidation reformer in which said fuel and oxidant are converted into a carbon-monoxide and hydrogen rich reformate, a first exothermally operated fuel cell stack downstream of the reformer, in which said carbon-monoxide and hydrogen rich reformate, as anode gas, and a cathode gas are converted to water and CO a second, non-exothermally operated fuel cell stack in which vapour reformation taking place is endothermal, wherein said first fuel cell stack and said second fuel cell stack are electrically connected in series with respect to the gas flow of the anode and cathode gases, and a second fuel supply means for admixing additional hydrocarbons to the anode waste gas before being introduced into the second fuel cell stack, a control unit which controls operation of the fuel cell system so that the first fuel cell stack is operated exothermally, the second fuel cell stack is operated non-exothermally, and so that heated anode waste gas containing water molecules from the first fuel cell stack is supplied to the second fuel cell stack in an uncooled state whereby the thermal energy from the exothermally operated first fuel cell stack is transferred via its anode and cathode waste gas to the second fuel cell stack for supplying the energy for endothermal vapour reformation in the second fuel cell stack, and wherein the control unit controls admixing the hydrocarbons to the anode waste gas from the first fuel cell stack in a molar ratio of water molecules to the hydrocarbons' carbon atoms of more than one.