Fuel cell system

A fuel cell system comprising:

• a fuel cell stack having one or more fuel cells;
• a discharging flow path discharging an exhaust from the fuel cell stack;
• a mixing tank supplying a fuel to the fuel cell stack;
• a radiator condensing water from the exhaust in a controlled amount and recycling the water to the mixing tank;
• a ventilator controllably feeding air to the radiator;
• and
• a controller unit controlling the ventilator so as to control the controlled amount,
• wherein the controller unit calculates the controlled temperature in accordance with an equation of
• P
• H
• 2
• ⁢
• O
• sat
• ⁡
• (
• T
• fin_cathode
• )
• =
• N
• ⁡
• (
• 2
• ⁢
• I
• op
• 6
• ⁢
• F
• +
• 2
• ⁢
• I
• c
• .
• o
• .
• 6
• ⁢
• F
• )
• F
• cathode_out
• ⁢
• P
• ,
• in which Tfin—cathode is the controlled temperature, Iop is a current generated by the fuel cells, Ic.o. is a proton current converted from a cluantity of a crossover methanol through the fuel cells. F is the Faraday constant, Fcathode —out is a flow rate of gas exhausted from the cathodes, N is a number of the fuel cells, and P is gas pressure in the radiator.

A fuel cell system comprising:

• a fuel cell stack having one or more fuel cells;
• a discharging flow path discharging an exhaust from the fuel cell stack;
• a mixing tank supplying a fuel to the fuel cell stack;
• a radiator condensing water from the exhaust in a controlled amount and recycling the water to the mixing tank;
• a ventilator controllably feeding air to the radiator;
• and
• a controller unit controlling the ventilator so as to control the controlled amount.
• wherein the controller unit calculates the controlled amount so as to balance the controlled amount of the condensed water with a demand in the fuel cells in accordance with an expression of NIop/6F, in which N is a number of the fuel cells, Iop is the current, and F is the Faraday constant.

A fuel cell system comprising:

• a fuel cell stack having one or more fuel cells;
• a discharging flow path discharging an exhaust from the fuel cell stack;
• a mixing tank supplying a fuel to the fuel cell stack;
• a radiator condensing water from the exhaust in a controlled amount and recycling the water to the mixing tank;
• a ventilator controllably feeding air to the radiator;
• and
• a controller unit controlling the ventilator so as to control the controlled amount,
• wherein the controller unit calculates the controlled amount so as to balance the controlled amount of the condensed water with a demand in the fuel cells to have water in an amount represented by an expression of
• N
• ·
• (
• 2
• ⁢
• I
• op
• 6
• ⁢
• F
• +
• 2
• ⁢
• I
• c
• .
• o
• .
• 6
• ⁢
• F
• )
• ,
• allowed to be exhausted to the atmosphere, in which N is a number of the fuel cells, Iop is the current generated by the fuel cell state, Ic.o. is a proton current converted from quantity of a crossover methanol through the fuel cell stack, and F is the Faraday constant.