Patent ID: 8257878

Claim:
A semi-passive type fuel cell system comprising: a stack having a stack upper end, a stack lower end, and a plurality of unit cells laterally stacked with one another, each unit cell including a membrane-electrode assembly and bipolar plates located on both sides of the membrane-electrode assembly, the membrane-electrode assembly having an electrolyte membrane, a cathode electrode, and an anode electrode, the electrolyte membrane having an electrolyte membrane first side surface and an electrolyte membrane second side surface, the cathode electrode being formed on the electrolyte membrane first side surface and the anode electrode being formed on the electrolyte membrane second side surface, the bipolar plates each having a bipolar plate upper end and a bipolar plate lower end; a heat transfer device configured to transfer heat from the stack lower end to the stack upper end comprising: a first heat transfer structure on the stack upper end; a second heat transfer structure on the stack lower end; and a heat pipe coupled to the first heat transfer structure and the second heat transfer structure and configured to transfer heat from the second heat transfer structure to the first heat transfer structure; means for supplying fuel to the stack; and means for supplying air to the stack, wherein each of the bipolar plates has air paths formed on a surface facing and contacting the cathode electrode and extending in an air path direction from the bipolar plate upper end to the bipolar plate lower end; wherein the means for supplying air includes ducts respectively installed on the stack upper end and the stack lower end and includes means for blowing air through the ducts, wherein the ducts comprise a first duct installed on the stack upper end and a second duct installed on the stack lower end, the first duct including a first duct first part and a first duct second part; wherein the means for blowing air through the stack are installed in the first duct first part and are offset from the air paths in a direction perpendicular to the air path direction; wherein the first duct second part includes a first duct second part left end and a first duct second part right end, the first duct second part left end being closest to the means for blowing air; and wherein an upper wall of the first duct second part is inclined downwards to have a predetermined inclination angle so that a height of the upper wall gradually decreases from the first duct second part left end to the first duct second part right end.