Fuel cell

A fuel cell comprising:

• a fuel cell body including an anode having an anode-side separator that is flat in a thickness direction and has projections and depressions formed on a surface of the anode-side separator, a cathode disposed so as to face the anode, and a membrane electrode assembly disposed between the anode and the cathode;
• a first fuel container for containing liquid fuel to be fed to the anode, the container housing at least the anode of the fuel cell body therein so as to be immersed in the liquid fuel and so as to feed the contained liquid fuel to the anode;
• a second fuel container for containing liquid fuel concentrate having a concentration higher than that of the liquid fuel contained in the first fuel container so as to feed the liquid fuel concentrate to the first fuel container;
• and
• a collection amount regulator for adjusting respective collection amounts of a product produced in the cathode to the first fuel container and the second fuel container, wherein
• the fuel cell body has passageways surrounded by the projections and depressions formed on the surface of the anode-side separator and a surface of the membrane electrode assembly, and
• the fuel passageways are connected to a feed port and a discharge port so as to extend in substantially one direction from the feed port to the discharge port, the discharge port being provided at a position higher than that of the feed port.