The present invention relates to methods and systems related to fuel cells, and in particular, to direct carbon fuel cells. The methods and systems relate to cleaning and removal of components utilized and produced during operation of the fuel cell, regeneration of components utilized during operation of the fuel cell, and generating power using the fuel cell.

In various aspects, a method for producing electricity by operating two or more turbines in series is provided. The method can include introducing, at least part of, the exhaust from an upstream turbine into a combustion chamber of a downstream turbine. In one aspect, exhaust from the upstream turbine is introduced into the downstream turbine's combustion chamber via the downstream turbine's compression chamber.

Systems and methods are provided for operating molten carbonate fuel cells to produce increased amounts of H.sub.2 in the anode effluent while still maintaining operation of the cell within conventional operation boundaries, such as having a temperature differential between the cathode input flow and the cathode effluent of 35 C. or more, with the cathode effluent being hotter than the cathode input flow. This temperature differential between the cathode input flow and the cathode effluent while still producing excess hydrogen is achieved in part by a) passing an input flow containing hydrocarbons and/or reformable fuel into an external reformer, b) reforming 20 vol % or more of the hydrocarbons and/or reformable fuel in the external reformer prior to c) passing the partially reformed input flow into a fuel cell or fuel cell stack where additional reforming is performed in the anode(s) and/or in a reforming element in the fuel cell stack.

Subject of the invention is a carbon capture system onboard a vessel which comprises an internal combustion engine for producing power and an exhaust gas, a molten carbonate fuel cell, which comprises a cathode and an anode, for producing electric energy, a cathode outlet stream and an anode outlet stream, wherein the cathode is in fluid communication with the internal combustion engine for receiving at least a portion of the exhaust gas, and a CO.sub.2 separation means which is in fluid communication with the anode for receiving at least a portion of the anode outlet stream, wherein the CO.sub.2 separation means is configured to separate CO.sub.2 from the at least a portion of the anode outlet stream for producing a CO.sub.2 rich stream and a CO.sub.2 depleted stream wherein the molten carbonate fuel cell has an electric connection with the CO.sub.2 separation means for at least partially using the electric energy to at least partially operate the CO.sub.2 separation means.

Systems and methods are provided for capturing CO.sub.2 from a combustion source using molten carbonate fuel cells (MCFCs). At least a portion of the anode exhaust can be recycled for use as part of anode input stream. This can allow for a reduction in the amount of fuel cell area required for separating CO.sub.2 from the combustion source exhaust and/or modifications in how the fuel cells can be operated.

A method of fabricating a fuel cell component for use with or as part of a fuel cell in a fuel cell stack, the method comprising: providing a fuel cell component, providing a deposition assembly for depositing loading material particles onto the fuel cell component, and actuating the deposition assembly to cause the deposition assembly to deposit said loading material particles onto said fuel cell component.

There is described a direct carbon fuel cell system. The system includes fuel cells, each fuel cell having a porous fuel cell anode and a fuel cell cathode. The system further includes a molten carbonate electrolyte and a fuel supply apparatus for flowing a fuel slurry having carbon particles and a carbon carrier fluid to the fuel cell anodes in parallel. The carbon carrier fluid has a same composition as the molten carbonate electrolyte. An oxidant supply apparatus flows an oxygen-containing stream to the fuel cell cathodes in parallel. An electrolyte circulation apparatus circulates the molten carbonate electrolyte in contact with each of the fuel cells. During operation of the direct carbon fuel cell system to generate electric power, carbon is oxidized at the fuel cell anodes to produce carbon dioxide, and at the fuel cell cathodes oxygen and carbon dioxide react to produce carbonate ions.

Cathode collector structures and/or corresponding cathode structures are provided that can allow for improved operation for a molten carbonate fuel cell when operated under conditions for elevated CO.sub.2 utilization. A cathode collector structure that provides an increased open area at the cathode surface can reduce or minimize the amount of alternative ion transport that occurs within the fuel cell. Additionally or alternately, grooves in the cathode surface can be used to increase the open area.

Molten carbonate fuel cell configurations are provided that include one or more baffle structures within the cathode gas collection volume. The baffle structures can reduce the unblocked flow cross-section of the cathode gas collection volume by 10% to 80%. It has been discovered that when operating a molten carbonate fuel cell under conditions for elevated CO.sub.2 utilization, the presence of baffles can provide an unexpected benefit in the form of providing increased transference and/or increased operating voltage.

Cathode collector structures and/or corresponding cathode structures are provided that can allow for improved operation for a molten carbonate fuel cell when operated under conditions for elevated CO.sub.2 utilization. A cathode collector structure that provides an increased open area at the cathode surface can reduce or minimize the amount of alternative ion transport that occurs within the fuel cell. Additionally or alternately, grooves in the cathode surface can be used to increase the open area.