Patent ID: 8197977

Claim:
A fuel cell system comprising: a fuel cell stack formed by stacking a plurality of fuel cells in a stacking direction, said fuel cells each being formed by stacking an electrolyte electrode assembly and a separator, said electrolyte electrode assembly including an anode, a cathode, and an electrolyte interposed between said anode and said cathode; a heat exchanger for heating an oxygen-containing gas using a heat medium before the oxygen-containing gas is supplied to said fuel cell stack; an evaporator for vaporizing water to produce a mixed fuel of a raw fuel chiefly containing hydrocarbon and water vapor; a reformer for performing steam reforming using the water vapor and the raw fuel to produce a fuel gas to be supplied to said fuel cell stack; and a combustor for burning the raw fuel to produce a combustion gas, wherein a fluid unit including at least said heat exchanger, said evaporator, and said reformer is provided at one end of said fuel cell stack in the stacking direction, and said combustor is provided inside said evaporator; and said combustor has a combustion gas path for discharging the combustion gas produced in said combustor, and said reformer is provided at a position in the middle of and in contact with said combustion gas path; and wherein said combustion gas path is connected to said heat exchanger for supplying the combustion gas after heating the reformer as a heat medium.