Zero gas emission system applied to hydrogen-oxygen fuel cell

Abstract

The invention belongs to the field of fuel cells, and particularly discloses a zero gas emission system applied to a hydrogen-oxygen fuel cell. The system comprises a fuel cell stack, a gas supply device and a buffer device, wherein the fuel cell stack is used as a reaction place of the hydrogen-oxygen fuel cell; the gas supply device comprises a hydrogen supply unit and an oxygen supply unit and is used for providing hydrogen and oxygen for the fuel cell stack; one end of a hydrogen buffer tank in a hydrogen buffer unit of the buffer device is connected with an anode gas outlet, and the other end is connected with an anode gas inlet through a first electromagnetic valve; and one end of an oxygen buffer tank in the oxygen buffer unit is connected with the cathode gas outlet, and the other end of the oxygen buffer tank is connected with the cathode gas inlet through a second electromagnetic valve. The static buffer container including the hydrogen buffer tank and the oxygen buffer tank is used for replacing dynamic circulation equipment, pressure difference is formed through switching gas supply of the gas supply unit and the buffer unit, water in the fuel cell stack is discharged, and the long-time stable operation capability of the fuel cell can be effectively improved.

Description

technical field [0001] The invention belongs to the field of fuel cells, and more specifically relates to a zero gas emission system applied to hydrogen-oxygen fuel cells. Background technique [0002] The main advantages of fuel cells for underwater propulsion are: (1) High energy conversion efficiency and specific energy. Fuel cells directly convert chemical energy into electrical energy without other intermediate steps and are not limited by the Carnot cycle. The energy conversion efficiency is higher than The heat engine is 2 to 3 times higher, and combined with the high-energy-density hydrogen-oxygen energy, the specific energy of the propulsion system can be greatly increased, which is conducive to increasing the range of the unmanned underwater vehicle. (2) Low vibration and noise, there are no moving parts inside the fuel cell, and there is no combustion like a heat engine, so the vibration and noise are low, which is conducive to improving the stealth of the unmanne...

AI Technical Summary

Problems solved by technology

However, during the long-term closed process of the stack, liquid water is continuously generated and accumulated in the battery, causing the battery to be flooded, which directly leads to the attenuation of battery performance and life, which will affect the current density distribution, material transportation and accelerate carbon corrosion.

[0004] The existing method is to circulate the gas through circulation pumps and other equipment to improve the gas utilization rate, but this will lead to problems such as increased noise and increased power consumption; when the battery is shut down, the inert gas is used to purge and remove the liquid water in the stack, which will cause fuel The problem of battery work pause and lag

CN111129545A discloses a vehicle fuel cell hydrogen circulation system and its control method. The method adopts a serpentine purge to drain water, but still needs to discharge hydrogen at the tail during operation, resulting in fuel loss

CN108075154A discloses a hydrogen-air proton exchange membrane fuel cell start-up and operation method without humidification conditions, without humidification, but needs to control the current density loading rate; CN105633433B discloses a method for draining water in a mobile body and a fuel cell system. The circulation pump discharges the liquid components separated from the exhaust gas, and only recovers the hydrogen gas, but the use of the circulation pump will increase the power consumption required by auxiliary equipment, and the use of a gas-liquid separator for liquid water separation increases the complexity of the equipment

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