CN212517257U - Structure of high-temperature fuel cell stack for hydrogen production by methanol reforming - Google Patents

Abstract

The utility model discloses a structure of a methanol reforming hydrogen production high-temperature fuel cell stack. The technical scheme of the utility model is that: the double-pole plate assembly comprises a first end plate, a second end plate, a double-pole plate assembly arranged between the first end plate and the second end plate and a screw assembly used for fixing the first end plate and the double-pole plate assembly, a flow equalizing cover plate and a bottom plate which are connected with the first end plate and the second end plate are respectively arranged above and below the double-pole plate assembly, the double-pole plate assembly comprises heat insulation plates and current collecting plates arranged on two sides, hydrogen and oxygen inlets and outlets are formed in the current collecting plates, the double-pole plate assembly comprises a plurality of reaction units connected in sequence, each reaction unit comprises two double-pole plates and a membrane electrode arranged between the two double-pole plates, a proton exchange membrane and a large sealing ring, a small sealing ring is arranged between the reaction units. The utility model provides a scheme pile cooling temperature difference, generated power are big, longe-lived and easy dismounting.

Description

Structure of high-temperature fuel cell stack for hydrogen production by methanol reforming

Technical Field

The utility model relates to a high temperature fuel cell technical field, in particular to structure of methyl alcohol reforming hydrogen manufacturing high temperature fuel cell pile.

Background

A high temperature fuel cell is a new type of power generation device that directly converts chemical energy of a fuel (such as hydrogen) and an oxidant (such as oxygen) into electrical energy. Because the energy conversion is not limited by the Carnot cycle and the additional product is only water, and because the water is in the high-temperature environment and the water is discharged along the bipolar plate flow channel in the form of water vapor, the high-temperature fuel cell has the characteristics of high energy conversion efficiency, environmental friendliness and the like. Hydrogen is the best fuel for fuel cells, and development of fuel cells is accelerated in large companies related to automobiles and energy sources in developed countries. At present, a plurality of technical difficulties exist in the links of hydrogen storage, transportation, distribution, filling and the like, so that the supply requirements of fuel cells of various scales cannot be met. Hydrogen-rich fuels such as alcohols and hydrocarbons move in a reforming mode or hydrogen is produced on site to provide a hydrogen source for a fuel cell, so that the hydrogen-rich fuel reforming method has the characteristics of high energy density, high energy conversion rate, easiness in transportation, convenience in carrying and the like, and has an advantage in the aspect of economic safety, and hydrogen production by reforming methanol and water is one of the effective reforming hydrogen production modes generally accepted by the market at present. The methanol reforming hydrogen production high-temperature fuel cell has the following advantages: 1. the safety performance is high, the methanol can be directly used for reforming hydrogen production, and the problem of hydrogen storage is not involved; 2. the bipolar plate has simple structure, the product water is discharged in a steam form in a high-temperature environment, and the bipolar plate has no water discharge flow channel; 3. the temperature difference of the electric pile is small, the efficiency is high, the cooling fan cover adopts a flow equalizing structure, and the cooling and the cathode runner are separated; 4. the requirement on the purity of hydrogen is low, and the requirement on the content of hydrogen in a high-temperature environment is low; 5. the tail gas emission is free of NOx and Sox, and the reforming hydrogen production reaction product is free of NOx, SOx and the like.

SUMMERY OF THE UTILITY MODEL

The main object of the present invention is to provide a structure of a high temperature fuel cell stack for methanol reforming hydrogen production, which has the advantages of temperature difference of stack cooling, large power generation, long service life and convenient assembly and disassembly.

In order to achieve the above purpose, the utility model provides a following technical scheme: the utility model provides a structure of methyl alcohol reforming hydrogen production high temperature fuel cell pile, includes first end plate, second end plate, sets up the bipolar plate subassembly between first end plate and second end plate and with the fixed screw assembly of first end plate, second end plate and bipolar plate subassembly, the top and the below of bipolar plate subassembly are provided with respectively and flow equalize apron and the bottom plate of being connected with first end plate and second end plate, the bipolar plate subassembly is including setting up heat insulating board and the collector plate in both sides, be provided with hydrogen and oxygen on the collector plate and import and export, the bipolar plate subassembly includes the reaction unit that a plurality of connected gradually, the reaction unit includes two bipolar plates and sets up membrane electrode, proton exchange membrane and the big sealing washer between two bipolar plates, is provided with little sealing washer between the reaction unit, be provided with the cooling runner on the bipolar plate.

Preferably, all be provided with on first end plate and the second end plate can with the apron that flow equalizes and the connecting block that the bottom plate is connected, the upper portion of the connecting block of first end plate sets up and the inlet opening that the apron communicates that flow equalizes, the lower part of the connecting block of second end plate sets up the exhaust vent that communicates with the bottom plate, be provided with the board that flow equalizes in the apron, be provided with a plurality of through-holes on the board that flow equalizes.

Preferably, the large sealing ring comprises a double-peak sealing ring tightly attached with the bipolar plate.

Preferably, the cooling flow channel is a serpentine flow channel.

Preferably, the through-holes include a small through-hole near the first end plate and a large through-hole near the second end plate.

Preferably, the screw assembly includes a screw, a nut, and a spring.

The utility model discloses have following advantage for prior art, can solve current fuel cell pile cooling temperature difference big, the generated power is low, and is short-lived, dismouting difficulty scheduling problem. The galvanic pile is sealed by locking the galvanic pile through the screw rod assembly, and each contact surface is sealed through the large sealing ring and the small sealing ring to prevent gas leakage. Referring to fig. 4, the reformed hydrogen gas enters the hydrogen flow channel of the bipolar plate along the axial direction through the inlet at one side of the collector plate, and the gas flows to the diagonally opposite outlet through the serpentine flow channel and flows out; referring to fig. 5, air enters the bipolar plate axially through an inlet on one side of the collector plate on the other end, and flows to an oblique angle outlet through a serpentine flow channel to flow out. The hydrogen in the flow channel of the bipolar plate reaches the proton exchange membrane coated with the catalyst through the gas diffusion layer on the membrane electrode, the hydrogen protons pass through the proton exchange membrane and then enter the oxygen side, the electrons pass through an external circuit and reach the oxygen side, and the hydrogen protons, the electrons and the oxygen molecules react through the catalyst to generate water to be discharged. Cooling air enters through the air inlet holes of the flow equalizing cover plate and the connecting block, cooling gas uniformly flows through the cooling flow channel of the bipolar plate of the galvanic pile through the flow equalizing plate, and the gas reaches the bottom plate and is discharged from the air outlet holes. Adopt bolted connection assembly between apron and bottom plate and two end plates flow equalizes, can dismantle the change convenience. The structure that the cooling air duct and the cathode air inlet duct are separated is adopted, so that the thickness of the bipolar plate is reduced, the whole volume is reduced, and the manufacturing cost is low.

Drawings

Fig. 1 is a schematic diagram of the overall structure of a high-temperature fuel cell stack for hydrogen production by methanol reforming according to the present invention;

FIG. 2 is a partial exploded view of the structure of a high temperature fuel cell stack for hydrogen production by methanol reforming according to the present invention;

FIG. 3 is a schematic structural view of a bipolar plate;

FIG. 4 is a flow path diagram of hydrogen gas;

FIG. 5 is a flow path diagram of oxygen;

FIG. 6 is a flow path diagram of air;

fig. 7 is a schematic structural view of a flow equalizing cover plate.

In the figure: 1. a first end plate; 2. a second end plate; 3. a screw assembly; 4. a bipolar plate assembly; 5. a flow equalizing cover plate; 6. a base plate; 7. a heat insulation plate; 8. a collector plate; 9. hydrogen and oxygen inlets and outlets; 10. a bipolar plate; 11. a membrane electrode; 12. a proton exchange membrane; 13. a large seal ring; 14. a small seal ring; 15. a cooling flow channel; 16. connecting blocks; 17. an air inlet hole; 18. an air outlet; 19. a flow equalizing plate; 20. and a through hole.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings.

As shown in fig. 1, a structure of a methanol reforming hydrogen production high-temperature fuel cell stack comprises a first end plate 1, a second end plate 2, a bipolar plate assembly 4 arranged between the first end plate 1 and the second end plate 2, and a screw assembly 3 for fixing the first end plate 1, the second end plate 2 and the bipolar plate assembly 4, wherein a flow equalizing cover plate 5 and a bottom plate 6 connected with the first end plate 1 and the second end plate 2 are respectively arranged above and below the bipolar plate assembly 4, the bipolar plate assembly 4 comprises heat insulating plates 7 and current collecting plates 8 arranged on two sides, hydrogen and oxygen inlets and outlets 9 are arranged on the current collecting plates 8, the bipolar plate assembly 4 comprises a plurality of reaction units connected in sequence, each reaction unit comprises two bipolar plates 10, and a membrane electrode 11, a proton exchange membrane 12 and a large sealing ring 13 arranged between the two bipolar plates 10, small sealing rings 14 are arranged between the reaction units, and cooling flow channels 15 are arranged on the bipolar plate 10.

Preferably, all be provided with the connecting block 16 that can be connected with the apron 5 and the bottom plate 6 flow equalize on first end plate 1 and the second end plate 2, the upper portion of the connecting block 16 of first end plate 1 sets up the fresh air inlet 17 with the apron 5 intercommunication that flow equalize, the exhaust vent 18 that communicates with the bottom plate 6 is set up to the lower part of the connecting block 16 of second end plate 2, be provided with the board 19 that flow equalize in the apron 5 that flow equalize, be provided with a plurality of through-holes 20 on the board 19 that flow equalize.

Preferably, the large seal ring 13 comprises a double-peak seal ring that is in close contact with the bipolar plate 10. The large sealing ring 13 adopts a cross-section double-peak sealing structure, so that gas is prevented from leaking under the condition of single-peak sealing failure.

Preferably, the cooling flow channel 15 is a serpentine flow channel.

Preferably, the through holes 20 comprise small through holes 20 close to the first end plate 1 and large through holes 20 close to the second end plate 2. The flow equalizing cover plate 5 with the through holes 20 in different sizes is adopted to ensure that the temperature difference of each bipolar plate 10 of the stack is small, the working efficiency and the service life of the stack are improved, the reason for the arrangement is that the air volume is larger at the position close to the first end plate 1, so the arranged through holes 20 are smaller, the larger through hole 20 at the back is arranged because the air volume is reduced, and the air inlet volume at each position of the bipolar plate assembly 4 is more or less or the temperature difference is smaller.

Preferably, the screw assembly 3 includes a screw, a nut, and a spring.

The structure of the methanol reforming hydrogen production high-temperature fuel cell stack can solve the problems of large cooling temperature difference, low power generation power, short service life, difficult disassembly and assembly and the like of the conventional fuel cell stack. The electric pile is sealed by locking the electric pile through the screw assembly 3, and each contact surface is sealed through the large sealing ring 13 and the small sealing ring 14, so that gas leakage is prevented. Referring to fig. 4, the reformed hydrogen gas enters the hydrogen flow channel of the bipolar plate 10 along the axial direction through the inlet at one side of the collector plate 8, and the gas flows to the diagonally opposite outlet through the serpentine flow channel and flows out; referring to fig. 5, air enters the bipolar plate 10 axially through an inlet on one side of the collector plate 8 on the other side, and flows through serpentine channels to an outlet on the diagonal side. The hydrogen in the flow channel of the bipolar plate 10 reaches the proton exchange membrane 12 coated with the catalyst through the gas diffusion layer on the membrane electrode 11, the hydrogen protons pass through the proton exchange membrane 12 and then enter the oxygen side, the electrons pass through the external circuit and reach the oxygen side, and the hydrogen protons, the electrons and the oxygen molecules react through the catalyst to generate water to be discharged. Cooling air enters through the air inlet holes 17 of the flow equalizing cover plate 5 and the connecting block 16, cooling gas uniformly flows through the cooling flow channels 15 of the stack bipolar plates 10 through the flow equalizing plate 19, and the gas reaches the bottom plate 6 and is discharged from the air outlet holes 18. The flow equalizing cover plate 5, the bottom plate 6 and the two end plates are connected and assembled through bolts, and can be detached and replaced conveniently. The bipolar plate 10 has a structure in which the cooling air duct and the cathode intake air duct are separated, so that the thickness is reduced, the overall volume is reduced, and the manufacturing cost is low.

It should be noted that, this scheme can be applicable to the field of methanol reforming hydrogen production fuel cell static power generation, because the influence of external environment, for example violent vibrations, striking etc. may cause the inside of the pile to shift, leak etc., so still not be fit for under the on-vehicle high shock condition, because violent vibrations cause the inside of the pile to shift, leak for a long time, and then influence the reduction of pile power generation, the life-span is shortened. But this scheme has very big application market prospect in static electricity generation aspect, like portable power generation case, the fixed power station in remote mountain area, island power station etc. have very obvious advantage.

It is above only the utility model discloses a preferred embodiment, the utility model discloses a scope of protection does not only confine above-mentioned embodiment, the all belongs to the utility model discloses a technical scheme under the thinking all belongs to the utility model discloses a scope of protection. It should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims (6)

1. A structure of a methanol reforming hydrogen production high-temperature fuel cell stack is characterized in that: including first end plate, second end plate, setting bipolar plate assembly between first end plate and second end plate and with first end plate, second end plate and the fixed screw rod subassembly of bipolar plate assembly, bipolar plate assembly's top and below are provided with respectively and flow equalize apron and the bottom plate of being connected with first end plate and second end plate, bipolar plate assembly is including setting up heat insulating board and the current collector plate in both sides, it imports and exports to be provided with hydrogen and oxygen on the current collector plate, bipolar plate assembly includes the reaction unit that a plurality of connected gradually, the reaction unit includes two bipolar plates and sets up membrane electrode, proton exchange membrane and the big sealing washer between two bipolar plates, is provided with little sealing washer between the reaction unit, be provided with the cooling flow way on.

2. The structure of a methanol reforming hydrogen production high-temperature fuel cell stack according to claim 1, characterized in that: the flow equalizing cover plate is characterized in that connecting blocks capable of being connected with the flow equalizing cover plate and the bottom plate are arranged on the first end plate and the second end plate respectively, an air inlet hole communicated with the flow equalizing cover plate is formed in the upper portion of the connecting block of the first end plate, an air outlet hole communicated with the bottom plate is formed in the lower portion of the connecting block of the second end plate, a flow equalizing plate is arranged in the flow equalizing cover plate, and a plurality of through holes are formed in the flow equalizing plate.

3. The structure of a methanol reforming hydrogen production high-temperature fuel cell stack according to claim 1, characterized in that: the large sealing ring comprises a double-peak sealing ring tightly attached to the bipolar plate.

4. The structure of a methanol reforming hydrogen production high-temperature fuel cell stack according to claim 1, characterized in that: the cooling flow channel is a snake-shaped flow channel.

5. The structure of a methanol reforming hydrogen production high-temperature fuel cell stack according to claim 2, characterized in that: the through holes include a small through hole near the first end plate and a large through hole near the second end plate.

6. The structure of a methanol reforming hydrogen production high-temperature fuel cell stack according to claim 1, characterized in that: the screw assembly comprises a screw, a nut and a spring.

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