Air Supply Method for Rapid Loading of Fuel Cells

Abstract

The invention provides an air supply method for fuel cell fast loading. By employing current I to control a corresponding air flow rate V, the method comprises the steps of: determining the real-time current I for increase of the initial current Ia to the final current Ib during fuel cell fast loading; diving the process for increase of the initial current Ia to the final current Ib into N steps, and determining the theoretical air flow rate Vn corresponding to the current In of each step according to the function formula Vn=f(In), n=1, 2, ..., N; and directed at the current In of any step, determining the actual air flow rate V'n=Vn+x=f(In+x), with x being greater than or equal to 1. The method provided by the invention adopts current rather than power as a representation of the fuel cell, and makes use of a step technique to control the air supply rate, so that normal fuel cell stack reaction can be ensured under a fuel cell fast loading state.

Description

technical field [0001] The invention relates to a vehicle-mounted fuel cell, in particular to a supply method for providing sufficient air supply when the fuel cell is rapidly loaded. Background technique [0002] A fuel cell is a device that directly converts chemical energy into electrical energy. Vehicle-mounted fuel cells are generally proton exchange membrane fuel cells (PEMFC), which mainly use hydrogen as fuel and air as oxidant. PEMFC has the advantages of high efficiency, no pollution, wide application, low noise, fast energy replenishment, and modular structure, so PEMFC is considered to be one of the ideal power sources for future vehicles. [0003] The reaction that takes place in a fuel cell is 2H 2 +O 2 →2H 2 O, where O 2 It mainly comes from air, and the ratio of the amount of air supplied to the amount of air required for complete reaction is called the excess air coefficient λ. Usually, to ensure the complete combustion of fuel, the air excess coefficie...

AI Technical Summary

Problems solved by technology

However, in the case of rapid loading, due to the rapid increase in power, the required air volume increases sharply, and the excess air coefficient will drop significantly if the supplied air volume is not correspondingly increased.

The consequence is that the carbon carrier of the catalyst in the fuel cell system will be damaged by oxidation and loss. In severe cases, the stack will even undergo a reverse reaction (ie, electrolysis reaction), which will lead to membrane perforation, accelerate the attenuation of battery performance, and seriously affect the life of the battery.

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