Water atomization apparatus for a fuel cell system and also a method for humidifying a gas flow supplied to a fuel cell system

Water atomization apparatus for a fuel cell system, the apparatus comprising a plurality of fuel cells connected together to form a fuel cell stack and each having an anode, a cathode and a membrane, said fuel cell stack having:

• an anode side with an inlet for a fuel and an outlet for non-consumed fuel and exhaust gases which arise at said anode side;
• a cathode side with an inlet for a gaseous oxidation agent and an outlet for exhaust gases arising at the cathode side;
• and
• a compressor connected upstream of the cathode side inlet, said water atomizing apparatus further comprising:
• a supply tank for deionized water;
• a pressure pump connected to said supply tank;
• a reservoir fed by said pressure pump and containing deionized water under pressure in operation;
• a pressure regulating valve having an inlet connected to said reservoir and determining an operating pressure which prevails therein;
• and
• at least one controllable injection valve adapted to inject atomized water into at least one of said cathode side and said anode side of said fuel cell stack.

A method for the humidification of a gas flow supplied to a fuel cell system, the method comprising:

• taking deionized water from water supply tank and forwarding it by means of a pressure pump into a reservoir for storing said deionized water under pressure;
• determining one of a preset pressure level and a predetermined pressure range in said reservoir by means of a valve;
• and
• injecting atomized water into said gas flow via at least one controllable injection valve connected to said reservoir.