Fuel cell, components and systems

A fuel cell comprising:

• (a) an anode comprising a porous substrate and a thin film disposed on the substrate, the thin film comprising a catalytic material;
• (b) a cathode;
• (c) a porous barrier interposed between the anode and cathode;
• (d) an anode-side channel defined between the anode and barrier for receiving a fuel-rich fluid;
• and
• (e) a cathode-side channel defined between the cathode and barrier for receiving a fuel-depleted fluid.

A fuel cell comprising:

• (a) an anode comprising a first anode section, a second anode section and a third anode section, the first and second anode sections each comprising a porous substrate for flowing a fuel/electrolyte combination therethrough, and the third anode section interposed between the first and second anode sections and fluidly communicating with the first and second anode sections;
• (b) a cathode comprising a first cathode section and a second cathode section;
• (c) a first channel interposed between the first anode section and the first cathode section;
• and
• (d) a second channel interposed between the second anode section and the second cathode section.

A fuel cell stack comprising:

• (a) a first side, a second side opposing the first side, a third side, and a fourth side opposing the third side;
• (b) a plurality of substantially planar electrodes arranged substantially parallel to each other and comprising respective edges defining the first, second, third, and fourth sides, the plurality of electrodes defining a plurality of first channels fluidly communicating with the first and second sides for conducting an oxygen-containing fluid generally from the first side to the second side, and defining a plurality of second channels fluidly communicating with the third and fourth sides for conducting a fuel/electrolyte combination generally from the third side to the fourth side;
• and
• (c) a device fluidly communicating with the second channels for removing water from the fuel/electrolyte combination by a pressure differential.

A method for operating a fuel cell comprising:

• (a) operating a plurality of electrodes comprising anodes and cathodes to collect electrons from the anodes;
• (b) switching the operation of at least one electrode to a refresh cycle whereby catalyst supported by the electrode is cleaned, wherein switching comprises disconnecting the at least one electrode from an electron-receiving load;
• and
• (c) applying an electric charge to one or more electrodes including the disconnected electrode.

A fuel cell comprising:

• (a) an anode;
• (b) a cathode;
• (c) a porous barrier interposed between the anode and cathode;
• (d) an anode-side channel defined between the anode and barrier for receiving a fuel-rich fluid;
• and
• (e) a cathode-side channel defined between the cathode and barrier for receiving a fuel-depleted fluid;
• and
• (f) a separator device communicating with the anode-channel and the cathode-side channel for separating fuel from a fluid processed by the anode.

A fuel cell stack comprising:

• (a) a first side, a second side opposing the first side, a third side, and a fourth side opposing the third side;
• (b) a plurality of substantially planar electrodes arranged substantially parallel to each other and comprising respective edges defining the first, second, third, and fourth sides, the plurality of electrodes defining a plurality of first channels fluidly communicating with the first and second sides for conducting an oxygen-containing fluid generally from the first side to the second side, and defining a plurality of second channels fluidly communicating with the third and fourth sides for conducting a fuel/electrolyte combination generally from the third side to the fourth side;
• and
• (c) a device fluidly communicating with the second channels for removing heat from the fuel/electrolyte combination.

A method for operating a fuel cell comprising:

• (a) operating a plurality of electrodes comprising anodes and cathodes to collect electrons from the anodes;
• (b) switching the operation of at least one electrode to a refresh cycle whereby catalyst supported by the electrode is cleaned;
• and
• (c) applying an electric charge to one or more electrodes whereby at least one of these electrodes undergoes the refresh cycle.

A method for operating a fuel cell comprising:

• (a) operating a plurality of electrodes comprising anodes and cathodes to collect electrons from the anodes;
• (b) switching the operation of at least one electrode to a refresh cycle whereby catalyst supported by the electrode is cleaned;
• (c) operating the at least one electrode in an electron-collecting cycle after cleaning the at least one electrode;
• and
• (d) switching the operation of at least one other electrode to the refresh cycle.

A method for operating a fuel cell comprising:

• (a) operating a plurality of electrodes comprising anodes and cathodes to collect electrons from the anodes;
• (b) switching the operation of at least one electrode to a refresh cycle whereby catalyst supported by the electrode is cleaned;
• and
• (c) flowing an electrolyte-containing fluid through at least one of the electrodes in a net forward direction that includes oscillatory components.

A method for operating a fuel cell comprising:

• (a) operating a plurality of electrodes comprising anodes and cathodes to collect electrons from the anodes;
• (b) switching the operation of at least one electrode to a refresh cycle whereby catalyst supported by the electrode is cleaned;
• and
• (c) flowing an electrolyte-containing fluid through the electrodes including the at least one electrode being refreshed.