CN213905418U

CN213905418U - Purging device and purging system for fuel cell

Info

Publication number: CN213905418U
Application number: CN202023242460.5U
Authority: CN
Inventors: 蔡永健; 徐冰; 周元昌; 陈卫; 陶建伟
Original assignee: Nekson Power Technology Co ltd
Current assignee: Nekson Power Technology Co ltd
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2021-08-06
Anticipated expiration: 2030-12-29

Abstract

The utility model relates to a sweep device and system of sweeping for fuel cell, wherein, the device includes the casing, and the casing is equipped with induction port, air inlet and gas outlet, and the induction port passes through shell cavity way intercommunication with the gas outlet, and says at shell cavity and be equipped with hydrogen absorption catalyst near the one end of gas outlet, and air inlet and shell cavity way intercommunication, and be equipped with the solenoid valve on the air inlet and the connection route that shell cavity said, and the solenoid valve is used for the intercommunication or cuts off being connected between air inlet and the shell cavity way. Utilize the utility model discloses a purging system can directly accomplish the cleaing away of the remaining hydrogen of pile through the hydrogen source in the stage of shutting down, improves fuel cell's life-span.

Description

Purging device and purging system for fuel cell

Technical Field

The utility model relates to a fuel cell technical field, concretely relates to a sweep device and system that sweeps for fuel cell.

Background

At present, the influence factors influencing the service life of the fuel cell are very many, wherein the ending process in the shutdown stage is a very important link, because after the fuel cell system is shut down, the anode of the fuel cell stack is filled with hydrogen, and the influence of two aspects can be caused:

because the gas partial pressure of the anode and the cathode is different, air (oxygen) permeates from the anode to the cathode or air is stopped for a long time and flows back and diffuses to the cathode area filled with hydrogen to form a hydrogen/air interface, so that high potential can be generated to cause serious corrosion to a catalyst carbon carrier, and finally the performance of the fuel cell is seriously degraded. Secondly, because the diffusion speed of hydrogen is far greater than that of air, negative pressure is formed inside the galvanic pile, the maximum negative pressure can reach about-80 kPa, and irreversible damage can be caused to the membrane in the long term.

Therefore, there is a great need in the art for a purging system for a fuel cell.

SUMMERY OF THE UTILITY MODEL

The present invention is directed to overcome the above-mentioned drawbacks of the prior art and to provide a purging device for a fuel cell with a strong purging capability.

The present application further provides a purging system formed by using the above purging device.

In order to achieve the purpose of the present invention, the present application provides the following technical solutions.

In a first aspect, the application provides a sweep device for fuel cell, the device includes the casing, the casing is equipped with induction port, air inlet and gas outlet, wherein, the induction port passes through shell cavity way intercommunication with the gas outlet, just the shell cavity way is close to the one end of gas outlet and is equipped with hydrogen and absorbs the catalyst, air inlet and shell cavity way intercommunication, just be in be equipped with the solenoid valve on the air inlet and the connected path that shell cavity said, the solenoid valve is used for the intercommunication or cuts off be connected between air inlet and the shell cavity way. The gas enters the shell of the purging device from the gas suction port and is discharged into the atmosphere through the shell inner cavity channel and the gas outlet, and due to the existence of the catalyst, the hydrogen is consumed, so that the shell inner cavity channel is in a negative pressure state, and the gas can be continuously sucked into the shell.

In one embodiment of the first aspect, the front end of the catalyst is provided with filter cotton.

In one embodiment of the first aspect, the catalyst is Pt/Al₂O₃。

In an implementation manner of the first aspect, an adjusting cavity is disposed in the housing, the adjusting cavity is located on a connecting pipeline between the solenoid valve and the housing inner cavity pipeline, and the adjusting cavity is connected with the housing inner cavity pipeline through an adjusting pipeline.

In one embodiment of the first aspect, a pipe diameter of an end of the regulating pipeline close to the regulating cavity is smaller than a pipe diameter of an end of the regulating pipeline close to the shell inner cavity.

In one embodiment of the first aspect, a muffler is provided at the air outlet.

In the second aspect, this application still provides a be equipped with as above the purge system for fuel cell who sweeps the device, the system includes hydrogen source, three-way valve, pile, discharge valve and sweeps the device, wherein, an import and the hydrogen source intercommunication of three-way valve, another import and the atmosphere of three-way valve are connected, the export of three-way valve and the access connection of pile, the import of discharge valve is connected with the gas vent of pile, discharge valve's export with the induction port of sweeping the device is connected, the air inlet and the hydrogen source of sweeping the device communicate with the connecting line of three-way valve.

In one embodiment of the first aspect, a filter is provided on a pipe connecting the three-way valve with the atmosphere.

Compared with the prior art, the beneficial effects of the utility model reside in that:

(1) after the fuel cell is stopped, the residual hydrogen in the galvanic pile can be removed more quickly, the corrosion of the hydrogen to a catalyst carrier in the galvanic pile is avoided, and the service life of the fuel cell is prolonged;

(2) in the process of removing the proton membrane, large pressure difference cannot be formed in the galvanic pile, and the service life of the proton membrane is prolonged.

Drawings

FIG. 1 is a schematic diagram of the connection of a purge system of the present application;

fig. 2 is a schematic structural view of the purging device in fig. 1.

In the figure, 1 electric pile, 2 purging device, 3 hydrogen source, 4 three-way valve, 5 exhaust valve, 6 filter, 7 silencer, 20 casing, 21 air inlet, 22 casing cavity channel, 23 filter cotton, 24 catalyst, 25 air outlet, 26 air inlet, 27 solenoid valve, 28 regulating cavity and 29 regulating pipeline.

Detailed Description

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as is understood by those of ordinary skill in the art to which the invention belongs. All numerical values recited herein as between the lowest value and the highest value are intended to mean all values between the lowest value and the highest value in increments of one unit when there is more than two units difference between the lowest value and the highest value.

In the following description of the embodiments of the present invention, it is noted that in the detailed description of the embodiments, all the features of the actual embodiments may not be described in detail in order to make the description concise and concise. Modifications and substitutions may be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and scope of the invention, and the resulting embodiments are within the scope of the invention.

Examples

The embodiments of the present invention will be described in detail below, and the embodiments are implemented on the premise of the technical solution of the present invention, and detailed embodiments and specific operation procedures are given, but the scope of the present invention is not limited to the following embodiments.

Example 1

A purging system for a fuel cell is structurally shown in figure 1 and comprises a hydrogen source 3, a three-way valve 4, a galvanic pile 1, an exhaust valve 5 and a purging device 2, wherein one inlet of the three-way valve 4 is communicated with the hydrogen source 3, the other inlet of the three-way valve 4 is connected with the atmosphere, a filter 6 is arranged on a connecting pipeline, an outlet of the three-way valve 4 is connected with an inlet of the galvanic pile 1, an inlet of the exhaust valve 5 is connected with an exhaust port of the galvanic pile 1, an outlet of the exhaust valve 5 is connected with the purging device 2, and a silencer 7 is arranged at an outlet of the purging device 2.

The structure of the purging device 2 is shown in fig. 2, and it includes a casing 20, the casing 20 has a suction port 21, an air inlet 26 and an air outlet 25, wherein, the suction port 21 communicates with the air outlet 25 through a casing inner cavity channel 22, and one end of the casing inner cavity channel 22 near the air outlet 25 is sequentially provided with a filter cotton 23 and a catalyst 24, and the suction port 21 is connected with the outlet of the exhaust valve 5 in fig. 1. The gas inlet 26 is communicated with the housing inner cavity passage 22, and a solenoid valve 27 and a regulating cavity 28 are sequentially arranged on a connecting path, the solenoid valve 27 is used for communicating or cutting off the connection between the gas inlet 26 and the housing inner cavity passage 22, and the gas inlet 26 is communicated with a connecting pipeline of the hydrogen source 3 and the three-way valve 4 in fig. 1. In addition, the regulating chamber 28 and the housing inner channel 22 are communicated through a regulating pipeline 29, and the pipe diameter of the regulating pipeline 29 at one end close to the regulating chamber 28 is small, and the pipe diameter of the regulating pipeline 29 at one end close to the housing inner channel 22 is large, namely the pipe diameter at a position is smaller than that at a position B shown in fig. 2.

The working principle of the purging system is as follows:

when the device is shut down, the hydrogen source 3 is kept open, an inlet connected with the hydrogen source 3 in the three-way valve 4 is closed, the inlet connected with the atmosphere in the three-way valve 4 is opened, the galvanic pile 1 is communicated with the atmosphere, the exhaust valve 5 is opened at the same time, the electromagnetic valve 27 in the purging device 2 is opened at last, at this time, the hydrogen source 3 enters the purging device 2 through the air inlet 26, and is discharged from the air outlet 25 after sequentially passing through the adjusting cavity 28, the adjusting pipeline, the shell inner cavity pipeline 22 and the catalyst 24, at this time, the air suction port 21 forms negative pressure, and because the air suction port 21 is communicated with the interior of the galvanic pile 1, and because the mass density of hydrogen is very small, the residual hydrogen in the galvanic pile 1 can be rapidly sucked out.

The principle that negative pressure is formed in the suction port is as follows:

the continuous equation for incompressible air gas according to fluid mechanics is known as follows:

S₁v₁＝S₂v₂

in the formula: s₁Is the cross-sectional area at A; s₂Is the cross-sectional area at B; v. of₁Is the fluid velocity at a; v. of₂Is the fluid velocity at B;

from the above equation, the area at B is significantly smaller than the area at A, and therefore the gas flow rate at B is also significantly larger than at A. Then, the energy equation of the constant flow of the incompressible gas (Bernoulli principle) can be used to know

When the height difference is ignored, the operation can be simplified into

The pressure at A is the pressure of the hydrogen source, and during the actual production process, the pressure of the hydrogen source is 136 KPa. When the shutdown was performed, the inside of the stack was in communication with the atmosphere, and therefore the pressure inside the stack was 101KPa, which was the atmospheric pressure, and the air inlet of the purge device was in communication with the inside of the stack, and therefore the pressure of the air inlet was also 101 KPa. From the above equation, the pressure decreases when the flow rate increases, and when the difference between the gas flow rates at points a and B is large enough, the gas pressure at point B is much lower than that at point a.

As can be seen from the formula, the value of the gas pressure at B depends on the gas pressure at A and the gas flow rates at A and B, and the gas flow rates at A and B depend on the cross-sectional areas at A and B. Therefore, as long as the cross-sectional sizes at a and B are sufficient, the air pressure at B can be less than atmospheric pressure, i.e., less than the pressure at the suction port. Therefore, the air flow can flow from the air suction port to the position B, and finally, all hydrogen in the electric pile is exhausted.

The embodiments described above are intended to facilitate the understanding and appreciation of the application by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present application is not limited to the embodiments herein, and those skilled in the art who have the benefit of this disclosure will appreciate that many modifications and variations are possible within the scope of the present application without departing from the scope and spirit of the present application.

Claims

1. A purging device for a fuel cell is characterized by comprising a shell, wherein the shell is provided with an air suction port, an air inlet and an air outlet, the air suction port is communicated with the air outlet through an inner cavity channel of the shell, a hydrogen absorption catalyst is arranged at one end of the inner cavity channel of the shell, which is close to the air outlet, the air inlet is communicated with the inner cavity channel of the shell, an electromagnetic valve is arranged on a connecting path of the air inlet and the inner cavity channel of the shell, and the electromagnetic valve is used for communicating or cutting off the connection between the air inlet and the inner cavity channel of the shell;

be equipped with the regulation chamber in the casing, it is located the connecting pipeline between solenoid valve and the shell inner chamber way to adjust the chamber, just adjust and be connected through the regulation pipeline between chamber and the shell inner chamber way, just the pipe diameter that the one end that the regulation pipeline is close to the regulation chamber is less than its pipe diameter that is close to shell inner chamber way one end.

2. A purge device for a fuel cell according to claim 1, wherein a filter cotton is provided at a front end of the catalyst.

3. The purge apparatus for a fuel cell according to claim 1, wherein the catalyst is Pt/Al₂O₃。

4. The purge apparatus for a fuel cell according to claim 1, wherein a muffler is provided at the gas outlet.

5. A purging system for a fuel cell provided with a purging device as claimed in any one of claims 1 to 4, the system comprising a hydrogen source, a three-way valve, a stack, an exhaust valve and the purging device, wherein one inlet of the three-way valve is connected to the hydrogen source, the other inlet of the three-way valve is connected to the atmosphere, the outlet of the three-way valve is connected to the inlet of the stack, the inlet of the exhaust valve is connected to the exhaust port of the stack, the outlet of the exhaust valve is connected to the suction port of the purging device, and the inlet of the purging device is connected to the connecting line of the hydrogen source and the three-way valve.

6. The purge system for a fuel cell according to claim 5, wherein a filter is provided on a line connecting the three-way valve with the atmosphere.