a cell of a solid electrolyte direct - flame fuel cell generates power in a state that the cell is placed inside or in the vicinity of a flame . the cell is configured in such a manner that a cathode layer is formed on one surface of a solid electrolyte layer and an anode layer is formed on the other surface . the cell is characterized by being curved so that the anode layer side has a concave shape and the cathode layer side has a convex shape .