CN215184093U

CN215184093U - Battery anode hydrogen circulation system

Info

Publication number: CN215184093U
Application number: CN202121411597.0U
Authority: CN
Inventors: 范爱民; 叶长流; 范德新; 罗子聪
Original assignee: Shunde Polytechnic
Current assignee: Shunde Polytechnic
Priority date: 2021-06-24
Filing date: 2021-06-24
Publication date: 2021-12-14
Anticipated expiration: 2031-06-24

Abstract

The utility model discloses a hydrogen circulation system of a battery anode, which comprises a high-pressure hydrogen source and a galvanic pile, and is characterized by also comprising a galvanic pile reaction route and a hydrogen injection route; the reactor reaction route comprises the high-pressure hydrogen source, an ejector, a heating and humidifying device and the reactor which are sequentially connected; the hydrogen injection route comprises the galvanic pile, a water-gas separator and the injector which are sequentially connected; hydrogen enters the galvanic pile from the galvanic pile reaction route to complete chemical reaction, and the residual hydrogen after reaction is sucked into the galvanic pile reaction route from the hydrogen injection route by the injector. The utility model discloses a set up endless recovery route, make inside surplus hydrogen of galvanic pile pass through backpressure device, moisture separator, get back to the ejector, participate in new galvanic pile chemical reaction along galvanic pile reaction route again, reach the complete utilization of hydrogen, avoid extravagant resource, practice thrift use cost.

Description

Battery anode hydrogen circulation system

Technical Field

The utility model relates to a new energy automobile technical field, more specifically say, relate to battery positive pole hydrogen circulation system.

Background

With the gradual deepening of the life theory of green environmental protection nowadays, more and more people begin to select new energy automobiles, especially hydrogen engine automobiles, because the fuel that the hydrogen engine used is gaseous hydrogen, what discharges is pure water, it has advantages such as pollution-free, zero release, reserves are abundant, and hydrogen engine automobile is the vehicle that really realizes zero release. However, since hydrogen is expensive and the hydrogen inside the reactor cannot completely react during the reactor reaction, the effective utilization rate is low, which results in waste of hydrogen and increased use cost.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a battery positive pole hydrogen circulation system provides a high-efficient circulated structure, reaches the purpose that can reuse unreacted hydrogen, realizes the complete utilization of hydrogen, avoids extravagant resource, practices thrift use cost.

The technical proposal of the utility model for solving the technical problem is that: a battery anode hydrogen circulation system comprises a high-pressure hydrogen source and an electric pile, and is characterized by also comprising an electric pile reaction route and a hydrogen injection route; the reactor reaction route comprises the high-pressure hydrogen source, an ejector, a heating and humidifying device and the reactor which are sequentially connected; the hydrogen injection route comprises the galvanic pile, a water-gas separator and the injector which are sequentially connected; hydrogen enters the galvanic pile from the galvanic pile reaction route to complete chemical reaction, and the residual hydrogen after reaction is sucked into the galvanic pile reaction route from the hydrogen injection route by the injector.

The reactor reaction route further comprises a pressure adjusting device and a mass flow meter, and the pressure adjusting device and the mass flow meter are connected between the high-pressure hydrogen source and the ejector.

The hydrogen injection route further comprises a backpressure device, and the backpressure device is connected between the galvanic pile and the water-gas separator.

The ejector comprises a nozzle, a suction chamber, a mixing chamber and a pressure expansion chamber, wherein the suction chamber is provided with a nozzle inlet and an ejected hydrogen inlet, and the pressure expansion chamber is in a conical cylinder shape.

The mixing chamber comprises a conical cylindrical mixing chamber inlet cavity and a cylindrical mixing chamber main cavity, and the diameter of an inlet of the mixing chamber inlet cavity is larger than that of an outlet of the mixing chamber inlet cavity.

The nozzle diameter Dn, the mixing chamber diameter Dm, and the mixing chamber major length Lm satisfy the following equation:

Dm/Dn=5.2、Lm/Dm=4。

the outlet end of the nozzle enters the mixing chamber through the suction chamber, and the distance between the outlet end of the nozzle and the joint of the suction chamber and the mixing chamber is 8 mm.

The utility model has the advantages that:

the utility model discloses be provided with endless recovery route, make the inside surplus hydrogen that does not participate in the chemical reaction of PEMFC pile pass through backpressure device, moisture separator, get back to the ejector, participate in new galvanic pile chemical reaction along galvanic pile reaction route again, reach the complete utilization of hydrogen, avoid extravagant resource, practice thrift use cost.

The ejector of the utility model has a scientific and reasonable structure, so that the ejection coefficient is ideal in the whole operation range, wherein the ejection coefficient corresponding to the peak power of 57.2kW is 1.31; the injection coefficient corresponding to 10.7kW at the low power point reaches 1.45, and the inlet pressure of the injector is increased but still within the working pressure range of the hydrogen injection valve.

Drawings

Fig. 1 is a schematic diagram of a hydrogen circulation system for a battery anode according to the present invention.

Fig. 2 is the schematic diagram of the ejector structure of the present invention.

Fig. 3 is a schematic size diagram of the ejector of the present invention.

Fig. 4 is a flow chart of the ejector size design of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "center", "lateral", "up", "down", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. "plurality" means two or more unless otherwise specified.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected. Can also be detachably connected or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases for those skilled in the art.

The fuel cell is an energy conversion device which directly converts chemical energy stored in reactants into electric energy through electrochemical reaction, and the energy conversion efficiency is high because the conversion process does not have the work of a heat engine and the limitation of Carnot cycle. In fuel cells, hydrogen gas is used as a carrier of energy, and its stable and efficient supply is closely related to the output power of the stack. In the conventional fuel cell at present, a hydrogen supply system mostly adopts a mode of stabilizing pressure and supplying more fuel quantitatively after a two-stage pressure reducing valve reduces pressure to provide enough fuel for a galvanic pile. Although the method can enable the fuel cell to meet the working requirement, when the electric pile is in a low-load area, the hydrogen is wasted due to excessive hydrogen supply, and the effective utilization rate is low; in the high load region, due to the large hydrogen demand, the hydrogen supply will be insufficient, and finally the fuel starvation and the power output will be insufficient, which seriously affects the working performance of the whole system. Therefore, the utility model discloses research and development an efficient hydrogen supply circulation system carries out the system integration through ejector and fuel cell pile and matches, can realize gaseous recovery and pressure boost under the condition that does not consume extra power, promotes fuel utilization and fuel cell efficiency.

Referring to fig. 1, the utility model discloses a battery anode hydrogen circulation system, draw the route including galvanic pile reaction route, hydrogen, galvanic pile reaction route: the system comprises a high-pressure hydrogen source 1, a pressure adjusting device 2, a mass flowmeter 3, an ejector 4, a heating and humidifying device 5 and a PEMFC pile 10.

Wherein, high pressure hydrogen source 1 is connected with pressure regulating device 2, and pressure regulating device 2 is connected with mass flow meter 3, and mass flow meter 3 is connected with ejector 4, and ejector 4 is connected with humidification device 5, and humidification device 5 is connected with PEMFC 10.

The pressure adjusting device 2 is used for adjusting the pressure.

Wherein the mass flow meter 3 can measure and control the flow of hydrogen into the reactor route.

The heating and humidifying device 5 is used for increasing the humidity and temperature of the hydrogen.

The hydrogen is output by a high-pressure hydrogen source 1, sequentially passes through a pressure regulating device 2, a mass flow meter 3, an ejector 4 and a heating and humidifying device 5, and finally reaches the interior of a PEMFC (proton exchange membrane fuel cell) galvanic pile 10 to perform chemical reaction with oxygen in the galvanic pile, so that the starting work of the galvanic pile is completed.

The unreacted hydrogen returns to the reactor reaction route from the hydrogen injection route. The hydrogen injection route is as follows: the device comprises a PEMFC pile 10, a backpressure device 6, a water-gas separation device 7, an ejector 4, a heating and humidifying device 5 and the PEMFC pile 10. The PEMFC pile 10 is connected with a back pressure device 6, the back pressure device 6 is connected with a water-gas separation device 7, and the water-gas separation device 7 is respectively connected with an exhaust valve 8, a drain valve 9 and an ejector 4 in a parallel mode.

The back pressure device 6 is used for realizing back pressure regulation of the battery.

The water-gas separation device 7 is used for screening residual substances, separating water from unreacted hydrogen and preventing water from entering a reactor reaction route. The residual substances after the galvanic pile reaction reach a water-gas separator 7 after passing through a backpressure device 6, water and gas are separated in the water-gas separator 7, redundant oxygen is discharged through an exhaust valve 8, redundant water is discharged through a drain valve 9, hydrogen which is not completely decomposed returns to an ejector 4, and then reaches a PEMFC 10 again through a heating and humidifying device 5 to participate in the reaction.

The structure and the size of the ejector 4 are shown in figures 2-3, and the ejector comprises a nozzle 41, a suction chamber A, a mixing chamber B and a diffusion chamber C, wherein the suction chamber is provided with two inlets, one inlet is arranged on a reactor reaction route, the nozzle 41 is inserted into an ejector inner cavity from the inlet, the other inlet is an ejected hydrogen inlet 42 connected with a hydrogen ejection route, and the mixing chamber is divided into two sections and comprises a conical mixing chamber inlet cavity 43 and a cylindrical mixing chamber main cavity 44. The diffuser chamber C is in the shape of a conical cylinder, is connected with the mixing chamber main cavity 44, and gradually increases in diameter. The mixing chamber inlet length is Lc, the mixing chamber main length is Lm, the injected hydrogen inlet diameter is Ds, the nozzle diameter Dn, the mixing chamber diameter Dm and the nozzle position size NXP, the mixing chamber inlet inclination angle is C, and the diffusion chamber inclination angle is P. The boundary of the suction chamber A and the mixing chamber B is used as an original point O, NXP is the size of the outlet end of the nozzle from the original point O, if NXP is positive, the outlet end of the nozzle is in the suction chamber A, and if NXP is negative, the outlet end of the nozzle enters the mixing chamber through the suction chamber. The structure of the ejector directly influences the ejection effect, and the hydrogen ejection coefficient reflects whether the ejector can eject low-pressure hydrogen (ejected humid gas output by the hydrogen ejection route). The hydrogen injection coefficient refers to the flow of low-pressure hydrogen which can be sucked when high-pressure hydrogen of unit mass passes through the injector under a certain working condition, and the key size influencing the performance of the injector is as follows: the nozzle diameter Dn, the mixing chamber diameter Dm, the mixing chamber major length Lm, and the nozzle position dimension NXP need to be sequentially searched for optimal values of the above parameters in the design process. And the screening of the optimal value is completed by simulation modeling and hydrogen injection ratio curve analysis. Simulation modeling parameter range: the power of the galvanic pile is in the range of 10kW-60 kW, the hydrogen inlet pressure of the galvanic pile is 0.3-1 bar, the hydrogen pressure drop of the galvanic pile is 0.02-0.07bar, and the mass flow is 0.1-1 g/s. And (4) modeling the simulation modeling according to different Dn, and performing simulation calculation according to multiple groups of operating conditions. According to the calculation result of the variable working condition, a change curve of Dn, an injection coefficient and main injection inlet pressure can be drawn, so that a parameter value with an available load range and injection performance reaching a better value can be found. With the reduction of the Dn value, the injection performance is enhanced, the available load range is widened, but the inlet pressure of the injector is increased, the inlet pressure of the injector is limited to be below the maximum working pressure Pmax =10barG of the hydrogen injection valve, and a better solution of Dn is obtained. After the Dn value is determined, a group of hydrogen injection coefficient curves are made by Dm/Dn within the range of 3-7 according to the operating condition and are subjected to comparative analysis to obtain the superior values of Dm/Dn and Lm/Dm, the NXP value is adjusted on the basis of the optimal parameter values, the optimal NXP value is found to be reduced along with the increase of the power of the stack, and the superior value range of the NXP value is determined; in the range, a larger value can obtain better ejection performance under a small load, so that the available load range of the ejector is widened. Taken together, the required NXP = -8mm is selected, the nozzle extending 8mm from the suction chamber into the mixing chamber, i.e. the distance between the end of the nozzle in the mixing chamber and the connection of the suction chamber and the mixing chamber is 8 mm. Dimension design flow of optimized dimensions referring to fig. 4, the optimized parameters are determined as follows:

Dn：1.5 mm。

Dm：7.8 mm。

Ds:12 mm。

Dm/Dn=5.2。

the mixing chamber has an inlet length Lc of 15.1 mm.

Mixing chamber major length Lm: 31.2 mm.

The length Ld of the pressure expansion chamber is 42.4 mm.

NXP=-8mm

∠C:19.7゜、∠P:7.5゜、Lm/Dm=4。

According to a simulation analysis result, the injection coefficient is improved in the whole operation range, wherein the injection coefficient corresponding to the peak power of 57.2kW is 1.31; the low power point is 10.7kW, and the corresponding injection coefficient is 1.45. The inlet pressure of the eductor is increased but still within the operating pressure range of the hydrogen injection valve.

The above is only the preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, many variations and modifications can be made without departing from the inventive concept, and these all fall into the protection scope of the present invention.

Claims

1. A battery anode hydrogen circulation system comprises a high-pressure hydrogen source and an electric pile, and is characterized by also comprising an electric pile reaction route and a hydrogen injection route; the reactor reaction route comprises the high-pressure hydrogen source, an ejector, a heating and humidifying device and the reactor which are sequentially connected; the hydrogen injection route comprises the galvanic pile, a water-gas separator and the injector which are sequentially connected; hydrogen enters the galvanic pile from the galvanic pile reaction route to complete chemical reaction, and the residual hydrogen after reaction is sucked into the galvanic pile reaction route from the hydrogen injection route by the injector.

2. The cell anode hydrogen circulation system of claim 1, wherein the stack reaction circuit further comprises a pressure regulating device and a mass flow meter, wherein the pressure regulating device and the mass flow meter are connected between the high pressure hydrogen source and the ejector.

3. The battery anode hydrogen circulation system of claim 1, wherein the hydrogen injection circuit further comprises a back pressure device connected between the galvanic pile and the moisture separator.

4. The battery anode hydrogen circulation system of claim 1, 2 or 3, wherein the ejector comprises a nozzle, a suction chamber, a mixing chamber, a pressure expansion chamber, the suction chamber is provided with a nozzle inlet and an ejected hydrogen inlet, and the pressure expansion chamber is in a conical cylinder shape.

5. The cell anode hydrogen circulation system of claim 4, wherein the mixing chamber comprises a conical cylindrical mixing chamber inlet cavity and a cylindrical main mixing chamber cavity, the mixing chamber inlet cavity having an inlet diameter greater than an outlet diameter.

6. The cell anode hydrogen circulation system of claim 5, wherein the nozzle diameter Dn, the mixing chamber diameter Dm, and the mixing chamber major length Lm conform to the following equation:

Dm/Dn=5.2、Lm/Dm=4。

7. the battery anode hydrogen circulation system of claim 5, wherein the outlet end of the nozzle passes through the inlet chamber into the mixing chamber, and the outlet end of the nozzle is 8mm from the junction of the inlet chamber and the mixing chamber.