Fuel cell auxiliary system and shutdown cathode rapid purging method

Abstract

The invention discloses a fuel cell auxiliary system and a shutdown cathode rapid purging method. The auxiliary system includes an air filter, an air flowmeter, an air compressor, an intercooler, an air bypass valve, a humidifier, an electric pile air incoming temperature sensor, an electric pile air outgoing humidity sensor, an air back pressure valve, an electric pile, an electric pile water outgoing temperature sensor, a water pump, an electric three-way valve, a radiator, a voltage sensor, an AC impedor and a current sensor. The auxiliary system is advantaged in that change of the system is little, parts are simple, and integration is facilitated; when a fuel cell is shutdown, an electric pile can be rapidly dried through purging, normal start at the next time is facilitated, and the auxiliary system can play the important role in the fuel cell vehicle field.

Description

technical field [0001] The invention relates to the technical field of fuel cell systems, in particular to a fuel cell auxiliary system and a method for quickly purging cathodes during shutdown. Background technique [0002] When the fuel cell system is running, the stack generates water on the cathode side through an electrochemical reaction. When the fuel cell system is shut down, the water on the cathode side of the stack needs to be blown dry to avoid flooding of the stack at the next startup and ensure normal startup. [0003] When the fuel cell system is applied on the vehicle, the vehicle is generally not equipped with nitrogen, so the stack is usually purged with air. Once hydrogen and air exist on both sides of the stack membrane, an open circuit voltage (>1V) will be generated, which is corrosive to the catalytic layer and carbon support of the fuel cell stack. Therefore, it is necessary to load current on the busbar of the stack during shutdown to reduce the a...

AI Technical Summary

Problems solved by technology

Once hydrogen and air exist on both sides of the stack membrane, an open circuit voltage (>1V) will be generated, which is corrosive to the catalytic layer and carbon carrier of the fuel cell stack.

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