CN214176087U

CN214176087U - Fuel cell stack and end plate thereof

Info

Publication number: CN214176087U
Application number: CN202120474888.8U
Authority: CN
Inventors: 刘行; 王仁芳; 石伟玉
Original assignee: Shanghai Jieqing Technology Co Ltd
Current assignee: Shanghai Hydrogen Propulsion Technology Co Ltd
Priority date: 2021-03-04
Filing date: 2021-03-04
Publication date: 2021-09-10
Anticipated expiration: 2031-03-04

Abstract

The utility model relates to a fuel cell stack and an end plate thereof, wherein, the end plate of the fuel cell stack comprises an end plate body and a reinforcing plate; the end plate body is provided with mounting holes along the circumferential direction; the reinforcing plate can be fixed with a side of the end plate body, and when the reinforcing plate is fixed, the reinforcing plate is in a compression state and forms an arc-shaped structure with the middle part protruding to one side of the end plate body, and the protruding part of the arc-shaped structure can be abutted to the end plate body. The fuel cell stack assembly structure has the advantages that after the fuel cell stack is assembled, the contact pressure inside the fuel cell stack is uniformly distributed, the output performance of the fuel cell stack is improved, the service life is prolonged, and meanwhile, the structure of the end plate is simple and the cost can be reduced.

Description

Fuel cell stack and end plate thereof

Technical Field

The utility model relates to a fuel cell technical field, concretely relates to fuel cell galvanic pile and end plate of fuel cell galvanic pile.

Background

Proton exchange membrane fuel cells are devices that utilize the electrochemical reaction of hydrogen and oxygen to produce electrical energy. The voltage output by the single battery is generally less than 1V, and the output power is limited. In order to provide voltage and power which meet the use requirements of electrical appliances, a plurality of single batteries are generally connected in series, end plates are used as supporting structures at two ends of each single battery, and the single batteries are fastened through screw rods and nuts to form a fuel cell stack.

A fuel cell stack generally consists of the following structure: the single cell is composed of two bipolar plates and a membrane electrode, leakage of reaction gas and cooling liquid is prevented through a sealing rubber line, and in order to guarantee the sealing performance of the sealing rubber line, a certain clamping force, namely the fuel cell stack assembly force, is required to be guaranteed between the end plates. In addition to maintaining the seal, some of the assembly force is used to maintain the contact pressure between the bipolar plate and the membrane electrode. Current is transmitted between the bipolar plate and the membrane electrode through contact, and contact resistance is generated at a contact interface. If the contact pressure is smaller, larger contact resistance is generated, and the overall output performance of the fuel cell stack is reduced; if the contact pressure is too large, irreversible mechanical damage is generated to the membrane electrode, and the service life of the fuel cell stack is shortened.

And a plurality of screws are arranged around the end plates, and the screws generate tensile force by screwing the nuts, so that a clamping effect is formed between the two end plates, and the fuel cell stack assembly is realized. Because the screw rods are distributed around the end plates, the end plates are easy to bend and deform under the action of the screw rods, so that the stress distribution in the fuel cell stack is uneven. The regions near the middle of the end plates are susceptible to under-stressing while the regions near the edge of the end plates are susceptible to over-stressing. The contact pressure between the bipolar plate and the membrane electrode in the area with insufficient stress is small, so that larger contact resistance is generated, and the overall output performance of the fuel cell stack is reduced. The contact pressure between the bipolar plate and the membrane electrode in the overpressure area is overlarge, so that irreversible mechanical damage is generated to the membrane electrode, and the service life of a fuel cell stack is shortened.

After the fuel cell stack is assembled, how to make the contact pressure inside the fuel cell stack be uniformly distributed, improve the output performance of the fuel cell stack and prolong the service life is a technical problem to be solved by technical personnel in the field.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a fuel cell pile and end plate of fuel cell pile can be at fuel cell pile equipment back for the inside contact pressure distribution of fuel cell pile is even, improves fuel cell pile output performance, increase of service life, the simple structure and the reduce cost of end plate simultaneously.

In order to solve the technical problem, the utility model provides an end plate of a fuel cell stack, which comprises an end plate body and a reinforcing plate; the end plate body is provided with mounting holes along the circumferential direction; the reinforcing plate can with a side of end plate body is fixed, and when fixed, the reinforcing plate is in the pressurized state and forms the middle part to the convex arc structure of one side of end plate body, just the bulge of arc structure can with end plate body butt.

When the reinforcing plate is in the fixed state with the end plate body, the reinforcing plate receives the extrusion and forms similar both ends and compare in the structure of middle part perk, middle part convex position and end plate body butt because the reinforcing plate is in compression state, consequently the reinforcing plate has the effort of recovering free state to this effort can drive the edge of end plate body to the trend of middle part perk.

When the end plate and the bottom plate are connected through the screw and the single battery clips are fastened in the mounting state, the acting force of the screw on the end plate body is located on the peripheral edge of the end plate body and is the same as the protruding direction of the reinforcing plate, the edge area of the end plate body bends towards one side of the bottom plate relative to the middle area under the action of the screw, and the middle area of the end plate body tends to arch towards the side far away from the bottom plate. Under the mounted state, the reinforcing plate is located the side that the end plate body kept away from the battery cell, the setting up of this reinforcing plate makes its orientation that produces the deformation trend to the end plate body and the effect of screw rod produces the deformation trend to the end plate body just opposite, consequently, the setting up of this reinforcing plate can improve the anti bending deformation ability of end plate under the mounted state, guarantee the overall structure stability of end plate, and then make the inside contact pressure distribution of fuel cell pile even, improve fuel cell pile output performance, increase of service life.

That is to say, through set firmly the reinforcing plate in the side of end plate body can guarantee that fuel cell pile inside contact pressure distributes evenly, simple structure and cost are lower.

Optionally, the end plate body is provided with a mounting groove towards one side end face of the reinforcing plate, and the reinforcing plate is located in the mounting groove.

Optionally, the length of the end plate is greater than the width, step structures are respectively arranged at two ends of the installation groove along the length direction of the end plate, and two ends of the reinforcing plate are respectively fixed with the step structures.

Optionally, the end of the reinforcing plate and the step structure are fixed by a fastener.

Optionally, a step surface of the step structure is provided with a threaded hole, two ends of the reinforcing plate are respectively provided with a through hole corresponding to each threaded hole, and the reinforcing plate is fixed to the step structure through a bolt.

Optionally, each of the through holes is arranged symmetrically about a center of the reinforcing plate.

Optionally, the material of the reinforcing plate is steel or aluminum.

Optionally, the end plate body is made of a metal material or an insulating material.

Optionally, the thickness of the end plate body is 10mm-30 mm.

The utility model also provides a fuel cell pile, it includes that end plate, bottom plate, screw rod, nut and clamp locate the end plate with a plurality of battery cells between the bottom plate, the both ends of screw rod are passed respectively the end plate with the bottom plate passes through the nut is fixed.

The technical effect of the fuel cell stack with the end plate is similar to that of the fuel cell stack, and is not repeated herein for saving space.

Drawings

Fig. 1 is a schematic structural diagram of a fuel cell stack according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of the end plate of FIG. 1;

fig. 3 is a cross-sectional view of the end plate.

In the accompanying fig. 1-3, the reference numerals are illustrated as follows:

100-end plate; 200-a base plate; 300-a single cell; 400-screw rod; 500-a nut; 1-end plate body, 11-mounting hole, 12-mounting groove, 13-step structure; 2-a reinforcing plate; and 3-bolts.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments.

Referring to fig. 1-3, fig. 1 is a schematic structural diagram of a fuel cell stack according to an embodiment of the present invention; FIG. 2 is a schematic structural view of the end plate of FIG. 1; fig. 3 is a cross-sectional view of the end plate.

The embodiment of the utility model provides an end plate 100 of fuel cell pile and fuel cell pile, wherein, as shown in fig. 1, the fuel cell pile includes end plate 100, bottom plate 200 and presss from both sides a plurality of battery cells 300 of locating between end plate 100 and bottom plate 200, and it is fixed through many screws 400 along circumference arrangement between end plate 100 and the bottom plate 200, and screw 400 passes end plate 100 and bottom plate 200 and fixes through nut 500 to press from both ends respectively with end plate 100 and bottom plate 200 and press from both sides each battery cell 300 that is located between the two.

Specifically, as shown in fig. 2 and 3, in the present embodiment, the end plate 100 includes an end plate body 1 and a reinforcing plate 2, wherein the end plate body 1 is provided with a mounting hole 11 along a circumferential direction thereof, the mounting hole 11 is used for being fixed to the bottom plate 200 by a screw 400, the reinforcing plate 2 can be fixed to one side surface of the end plate body 1, and when the reinforcing plate 2 is fixed to the end plate body 1, the reinforcing plate 2 is in a compressed state and forms an arc-shaped structure with a middle portion protruding to one side of the end plate body 1, and a protruding portion of the arc-shaped structure can abut against the end plate body 1.

As shown in fig. 3, when reinforcing plate 2 and end plate body 1 are in fixed state, reinforcing plate 2 receives the extrusion and forms similar both ends and compare in the structure of middle part perk, the convex position in middle part and end plate body 1 butt, because reinforcing plate 2 is in compression state, consequently reinforcing plate 2 has the effort of recovering free state to this effort can drive the edge of end plate body 1 to the trend of middle part perk.

In the mounted state, when the end plate 100 and the bottom plate 200 are connected by the screws 400 and the respective unit cells 300 are sandwiched and fastened, the force of the screws 400 on the end plate body 1 is located at the outer peripheral edge of the end plate body 1 in the same direction as the protruding direction of the reinforcing plate 2, the end plate body 1 is caused by the screws 400 to bend in the edge region toward the side of the bottom plate 200 with respect to the middle region, and the middle region of the end plate body 1 tends to arch toward the side away from the bottom plate 200. Under the mounted state, reinforcing plate 2 is located the side that single cell 300 was kept away from to end plate body 1, the setting up of this reinforcing plate 2 makes its orientation that produces the deformation trend to end plate body 1 and screw rod 400's effect produce the deformation trend to end plate body 1 just opposite, consequently, the setting up of this reinforcing plate 2 can improve the anti bending deformation ability of end plate 100 under the mounted state, guarantee end plate 100's overall structure stable, and then make the inside contact pressure distribution of fuel cell pile even, improve fuel cell pile output performance, and the service life is prolonged.

That is to say, in this embodiment, the reinforcing plate 2 is fixedly arranged on one side of the end plate body 1, so that the uniform distribution of the internal contact pressure of the fuel cell stack can be ensured, the structure is simple, and the cost is low.

In the above embodiment, the end plate body 1 is further provided with the mounting groove 12 towards one side end face of the reinforcing plate 2, the reinforcing plate 2 is located in the mounting groove 12, the mounting groove 12 can be used for accommodating the reinforcing plate 2, and meanwhile, compared with the case that the reinforcing plate 2 is directly arranged on the end face of the end plate body 1, the overall height of the fuel cell stack can be reduced, and meanwhile, the overall weight of the end plate 100 can also be reduced. Specifically, in this embodiment, the depth of the mounting groove 12 is not required, and may be set according to the structural strength requirement, the thickness of the end plate body 1, the height of the reinforcing plate 2, and the like.

In the above embodiment, the length of the end plate 100 is greater than the width, the step structures 13 are respectively disposed at two ends of the installation groove 12 along the length direction of the end plate 100, and two ends of the reinforcing plate 2 are respectively fixed with the step structures 13. Or, the end of the reinforcing plate 2 can extend out of the mounting groove 12 and be fixed with the end face of the end plate body 1, and the step structure 13 can ensure that at least most (even all) of the reinforcing plate 2 is located in the mounting groove 12, so as to further reduce the overall height of the end plate 100.

Specifically, as shown in fig. 1 to 3, the end plate 100 is a rectangular structure, the mounting groove 12 and the reinforcing plate 2 are also rectangular structures, and the step structures 13 are disposed at two ends of the mounting groove 12 in the length direction, of course, the shape of the mounting groove 12 also changes with the change of the shape of the end plate 100, when the end plate 100 is a square structure (i.e., the length and the width are equal), the mounting groove 12 and the reinforcing plate 2 are also square structures, at this time, the reinforcing plate 2 may be a structure in which the middle area protrudes and the peripheral edge tilts after being fixed to the end plate body 1, the step structures 13 are disposed at two opposite sides of the mounting groove 12, or the step structures 13 are disposed around the mounting groove 12; similarly, when the end plate 100 is of a circular configuration, the mounting groove 12 and the reinforcing plate 2 are also of a circular configuration.

Further, the step surface of the step structure 13 is provided with a threaded hole, two ends of the reinforcing plate 2 are respectively provided with a through hole corresponding to each threaded hole, and the reinforcing plate 2 is fixed with the step structure 13 through the bolt 3. Of course, in this embodiment, the end of the reinforcing plate 2 may be fixed to the stepped structure 13 by riveting, and when the reinforcing plate 2 is fixed by the bolt 3, the tightening amount of the bolt may be adjusted, and since the reinforcing plate 2 has an arc-shaped structure, the end surface of the bolt 3 is not completely attached to the reinforcing plate 2, and specifically, the bending radian of the reinforcing plate 2 may be adjusted by changing the tightening amount of the bolt 3 between the reinforcing plate 2 and the stepped structure 13, so that the deformation state of the end plate 100 may be adjusted, and the bending deformation resistance of the end plate may be improved. Moreover, the pre-deformation of the end plate 100 can be adjusted according to different assembly requirements, which is more beneficial to the assembly and matching of the fuel cell stack.

Furthermore, in the present embodiment, the through holes of the reinforcing plate 2 are symmetrically arranged with respect to the center of the reinforcing plate 2, that is, the bolts 3 for fixing the reinforcing plate 2 and the end plate body 1 are symmetrically arranged with respect to the center of the reinforcing plate 2, so that the reinforcing plate 2 can be uniformly stressed, and the service life of the reinforcing plate 2 can be ensured.

In the above embodiment, the material of the reinforcing plate 2 is a high-strength metal material such as steel or aluminum, so as to ensure that the reinforcing plate 2 has the required structural strength, and at the same time, the thickness of the reinforcing plate 2 can be reduced, thereby reducing the overall weight of the end plate 100.

In the above embodiment, the end plate body 1 is made of metal to ensure the structural strength of the end plate body 1, or the end plate body 1 may be made of insulating material, specifically, high-strength insulating material, such as epoxy resin and glass fiber reinforced resin. Therefore, the arrangement of the insulating plate between the end plate 100 and the current collecting plate can be eliminated, the number of parts of the fuel cell stack is reduced, the integral structure is simplified, the integral size of the fuel cell stack can be reduced, and the arrangement is convenient.

In the above embodiment, the thickness of the end plate body 1 is 10mm to 30mm, and the reinforcing plate 2 can improve the overall bending resistance of the end plate 100, so that the thickness of the end plate body 1 can be set to be thin, the weight and the cost can be reduced on the basis of ensuring the structural strength of the end plate 100, and the overall height of the fuel cell stack can be reduced.

In addition, in the present embodiment, the number of the screws 400 and the number of the bolts 3 for mounting the reinforcing plate 2 are not limited, and may be set according to actual conditions.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.

Claims

1. An end plate of a fuel cell stack, characterized by comprising an end plate body (1) and a reinforcing plate (2);

the end plate body (1) is provided with mounting holes (11) along the circumferential direction;

reinforcing plate (2) can with a side of end plate body (1) is fixed, and when fixed, reinforcing plate (2) are in compression state and form the middle part to the convex arc structure of one side of end plate body (1), just the bulge of arc structure can with end plate body (1) butt.

2. The end plate of a fuel cell stack according to claim 1, wherein the end plate body (1) is further provided with a mounting groove (12) at a side end surface facing the reinforcing plate (2), and the reinforcing plate (2) is located in the mounting groove (12).

3. The end plate of a fuel cell stack according to claim 2, wherein the length of the end plate is greater than the width of the end plate, step structures (13) are respectively arranged at two ends of the installation groove (12) along the length direction of the end plate, and two ends of the reinforcing plate (2) are respectively fixed with the step structures (13).

4. The end plate of a fuel cell stack according to claim 3, wherein the end of the reinforcement plate (2) and the step structure (13) are fixed by a fastener.

5. The end plate of the fuel cell stack according to claim 4, wherein the stepped surface of the stepped structure (13) is provided with threaded holes, both ends of the reinforcing plate (2) are respectively provided with through holes corresponding to the threaded holes, and the reinforcing plate (2) is fixed to the stepped structure (13) by bolts (3).

6. The end plate of a fuel cell stack according to claim 5, wherein each of the through-holes is arranged symmetrically with respect to the center of the reinforcing plate (2).

7. End plate of a fuel cell stack according to any of claims 1-6, characterized in that the material of the reinforcement plate (2) is steel or aluminium.

8. End plate of a fuel cell stack according to any of claims 1-6, characterized in that the end plate body (1) is of a metallic or insulating material.

9. End plate of a fuel cell stack according to any of claims 1-6, characterized in that the thickness of the end plate body (1) is 10mm-30 mm.

10. The fuel cell stack is characterized by comprising an end plate, a bottom plate (200), a screw (400), a nut (500) and a plurality of single cells (300) clamped between the end plate and the bottom plate (200), wherein two ends of the screw (400) respectively penetrate through the end plate and the bottom plate (200) and are fixed through the nut (500).