CN112002922A

CN112002922A - Sealing structure of fuel cell stack

Info

Publication number: CN112002922A
Application number: CN202010888951.2A
Authority: CN
Inventors: 朱景兵; 秦臻; 杨克蒋; 施正荣
Original assignee: Zhejiang Haihao New Energy Technology Co ltd
Current assignee: Zhejiang Haihao New Energy Technology Co ltd
Priority date: 2020-08-28
Filing date: 2020-08-28
Publication date: 2020-11-27

Abstract

The invention discloses a sealing structure of a fuel cell stack, the fuel cell stack comprises at least 1 single cell provided with an anode plate, a membrane electrode and a cathode plate, the inner peripheries of the surfaces of the anode plate and the cathode plate in each single cell are respectively provided with an active area for arranging a reducing agent channel and an oxidizing agent channel, the active areas are contacted with the membrane electrode, the peripheries of the anode plate, the cathode plate and the membrane electrode are sealed and pressed, the outer peripheries of at least 1 surface of the anode plate and/or the cathode plate and/or the membrane electrode at least comprise a first closed sealant line channel and a second closed sealant line channel, and the first closed sealant line channel and the second closed sealant line channel are distributed in parallel interval or non-parallel interval distribution and are used for realizing multiple sealing effects on the single cell; the invention greatly reduces the leakage probability possibly caused by a single sealing rubber wire, and can powerfully improve the power density of the fuel cell stack.

Description

Sealing structure of fuel cell stack

Technical Field

The invention relates to the field of fuel cell manufacturing, in particular to a sealing structure of a fuel cell stack.

Background

A fuel cell is a chemical device that directly converts chemical energy of fuel into electrical energy, and is also called an electrochemical generator. The fuel cell converts the Gibbs free energy in the chemical energy of the fuel into electric energy through electrochemical reaction, is not limited by Carnot cycle effect, and has high energy conversion rate; the reaction product of the fuel cell which adopts hydrogen as fuel is water, so that the method is environment-friendly and can realize zero-pollution emission theoretically; in addition, the fuel cell has no mechanical transmission part, few moving parts and low noise during working; the fuel cell has the advantages of high specific energy, high reliability, wide fuel range, short starting time, small volume, convenient carrying and the like. It follows that fuel cells are currently the most promising power generation technology from the viewpoint of energy conservation and ecological environment conservation.

Structurally, a fuel cell generally includes a membrane electrode (also referred to as MEA) and a Current Collector (Current Collector); among them, the membrane electrode of the fuel cell is an electrochemical reaction site where a reducing agent (typically, a fuel such as methanol or hydrogen) undergoes an oxidation reaction and an oxidizing agent (typically, oxygen or air) undergoes a reduction reaction. The conventional membrane electrode mainly comprises a proton exchange membrane (also called PEM membrane) which is located in the middle and both sides of which are respectively provided with a cathode and an anode integrally, and gas diffusion layers (also called GDL membranes) which are respectively located on the upper surface and the lower surface of the proton exchange membrane, wherein in order to promote the occurrence of electrochemical reaction, a catalyst (usually located at the interface between the proton exchange membrane and the gas diffusion layers) is also generally arranged among the cathode, the anode and the proton exchange membrane; the current collector is also called Bipolar Plate (Bipolar Plate) and is responsible for distributing fuel and air to the surfaces of the cathode and anode and for dissipating heat of the stack, and is also a key component responsible for connecting the single cells in series to form a fuel cell stack, and mainly plays a role in separating an oxidant, a reducing agent and a coolant and collecting current.

In actual manufacture, seals are required between fluid transfer passages (e.g., a reducing agent or an oxidizing agent or a coolant) within the fuel cell stack, as well as between the fluid transfer passages and the exterior of the stack. Leakage of fluid or mixing of different fluids within the stack not only results in waste, reduces the performance of the stack, but may also cause safety hazards. In practical applications, the total length of the sealing line of a 100 kw fuel cell stack may reach about 1 km, and therefore, the sealing technology in the fuel cell stack technology has a great influence on the safety, life, efficiency, and other aspects of the stack.

In the prior art fuel cell stack, an embedded groove is usually provided at the edge of the graphite or metal electrode plate to be sealed, a sealing gasket is placed in the embedded groove, or a circle of glue is applied at the sealed edge by a glue applicator to realize sealing after curing and pressing. However, these sealing methods generally face at least one of the following technical problems:

a. there is generally only a single leak-proof seal path, with a high risk of seal failure.

b. A good seal is formed by applying a large pressure to the sealing ring, so that a large stress is formed in a local area of the pole plate, which easily causes damage or distortion of the pole plate.

c. Grooves need to be preset on the polar plates, so that the thickness requirement of the polar plates is increased, and the power density of the fuel cell stack is reduced.

d. The single sealing ring or the sealing rubber line is easy to generate plastic deformation, and the sealing failure risk is higher.

Therefore, based on the above state of the art, the present applicant has sought a new sealing technical solution to effectively improve the sealing performance of the fuel cell stack.

Disclosure of Invention

In view of this, an object of the present invention is to provide a sealing structure of a fuel cell stack, which greatly reduces the leakage probability possibly caused by a single sealing glue line, and can forcefully improve the power density of the fuel cell stack.

The utility model provides a seal structure of fuel cell pile, the fuel cell pile includes 1 at least monocell that is equipped with anode plate, membrane electrode and negative plate, and the anode plate in every monocell and negative plate surface inner periphery are equipped with the active area that is used for setting up reductant passageway and oxidant passageway respectively, and this active area contacts with the membrane electrode, just sealed pressfitting between anode plate, negative plate and the membrane electrode frame, the anode plate and/or the periphery of 1 at least surface of cathode plate and/or membrane electrode includes first closed form sealed glue line way and second closed form sealed glue line way at least, first closed form sealed glue line way with second closed form sealed glue line way is parallel interval distribution or non-parallel interval distribution, is used for realizing to the multiple sealed effect of monocell.

Preferably, the outer peripheries of the upper and lower surfaces of the anode plate and/or the cathode plate and/or the membrane electrode each include at least a first closed sealant lane and a second closed sealant lane, and the first closed sealant lane and the second closed sealant lane of the upper and lower surfaces of each plate or membrane electrode are vertically and symmetrically distributed with respect to the bipolar plate or membrane electrode.

Preferably, 1 or more sealing partition glue lines distributed at intervals are arranged between adjacent closed sealing glue lines, and two ends of each sealing partition glue line are respectively connected with 1 closed sealing glue line.

Preferably, the shape of the preset closed sealant lane is taken as a target pattern, the sealant is arranged on the periphery of the surface of the anode plate or the cathode plate or the membrane electrode through a screen printing process or an ink-jet printing or gluing process or a brushing process, and the closed sealant lane is obtained through curing and molding.

Preferably, the end part of the sealing glue on the surface of the polar plate or the membrane electrode is in a convex arc shape.

Preferably, before the sealant is cured and formed, the anode plate, the membrane electrode frame and the cathode plate are pressed into a whole in advance, and then the whole is cured and sealed.

Preferably, after the sealant is cured and molded, the anode plate, the membrane electrode frame and the cathode plate are sealed and pressed into a whole.

Preferably, the surface of the polar plate is provided with surface undulations with rough characteristic structures, so that firm bonding between each glue line and the surface of the polar plate is facilitated.

Preferably, the surface relief height is less than the height of the closed sealant lane.

Preferably, the number of the closed sealant lines is 2-300, and/or the width of the closed sealant lines is 30-500 micrometers, and/or the height of the closed sealant lines is 3-100 micrometers, and/or the aspect ratio of each closed sealant line is 0.1-1. The polar plate related to the application can be a silicon polar plate, a graphite polar plate, a metal polar plate, a ceramic polar plate, a composite polar plate or other suitable materials, and the material of the polar plate is not particularly limited; the fuel cell according to the present invention may be a fuel cell cooled by cooling water, a fuel cell cooled by air cooling, or a fuel cell having another structure, and the present invention is not particularly limited thereto.

The application relates to a sealed including in the fuel cell pile, between the polar plate of adjacent monocell, between polar plate and the membrane electrode to and the sealed effect between polar plate and the pile external structure, mainly can realize: a reductant fluid (e.g., hydrogen), an oxidant fluid (e.g., oxygen or air), and a cooling medium (e.g., cooling water, if any).

Because the sealing effect of the sealing structure mainly depends on the pressure intensity of the sealing structure, the larger the pressure intensity is, the better the sealing performance of the fuel cell is, under the same pressure condition, in order to ensure that a single sealing structure has enough pressure intensity, the width of the glue line is enlarged, so that the pressure intensity cannot be improved, and the negative influence is caused on the sealing effect; therefore, the present application creatively has the following positive technical effects compared with the sealing mode of adopting a sealing gasket or beating a circle of rubber ring in the prior art by arranging a plurality of closed sealing rubber tracks on the outer periphery of the surface of the pole plate:

1. due to the fact that multiple sealing effects on the monocells are achieved, the possibility of leakage possibly caused by a single sealing glue line is greatly reduced; in practical application, the leakage probability of the structure with n closed sealant lines is n times of the leakage probability of a single sealant, so that the leakage probability of the fuel cell is obviously reduced; the application further provides that a sealing partition glue line is arranged between the adjacent spaced closed sealing glue line channels, and the leakage probability of the fuel cell can be further reduced through partition in the partition area.

2. The thin sealant channels which are as level as possible with the surfaces of the polar plates can be printed through the printing glue lines, so that the leakage probability among the polar plates and between the polar plates and the frame of the membrane electrode in the fuel cell is greatly reduced, and the sealing performance of the single sealant channel is effectively improved.

3. The structure of avoiding adopting seal ring is favorable to reducing the thickness of single cell in the fuel cell on the basis of guaranteeing excellent sealed effect, consequently can promote the power density of fuel cell pile powerfully.

Drawings

FIG. 1 is a schematic view of the structure of a single cell 1 in a fuel cell according to an embodiment of the present invention;

FIG. 2 is a schematic view of the seal end 40 on the plate according to the present embodiment;

FIG. 3 is a schematic structural diagram of a plate in example 1 of the present application;

FIG. 4 is an enlarged view of the structure of FIG. 3 at A;

FIG. 5 is a schematic structural diagram of a plate in example 2 of the present application;

FIG. 6 is an enlarged view of the structure at B in FIG. 5;

FIG. 7 is a partial structural view of a plate in example 3 of the present application;

FIG. 8 is a partial structural view of a plate in example 4 of the present application;

FIG. 9 is a schematic structural diagram of a plate in example 5 of the present application;

FIG. 10 is an enlarged view of the structure of FIG. 9 at C;

FIG. 11 is a schematic structural view of a plate in example 6 of the present application;

fig. 12 is an enlarged view of the structure at D in fig. 11.

Detailed Description

The embodiment of the invention discloses a sealing structure of a fuel cell stack, which comprises at least 1 single cell provided with an anode plate, a membrane electrode and a cathode plate, wherein the inner peripheries of the surfaces of the anode plate and the cathode plate in each single cell are respectively provided with an active area for arranging a reducing agent channel and an oxidizing agent channel, the active areas are contacted with the membrane electrode, the peripheries of the anode plate, the cathode plate and the membrane electrode are sealed and pressed, the outer peripheries of at least 1 surface of the anode plate and/or the cathode plate and/or the membrane electrode at least comprise a first closed sealant line channel and a second closed sealant line channel, and the first closed sealant line channel and the second closed sealant line channel are distributed in parallel interval or non-parallel interval, so that the multiple sealing effect on the single cell is realized.

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1: referring to fig. 1, a sealing structure of a fuel cell stack, the fuel cell stack includes at least 1 single cell 1 provided with an anode plate 10, a membrane electrode 20 (the outer periphery of which is provided with a membrane electrode frame 20a, which may be made of a known PCT material), and a cathode plate 30, in this embodiment, the fuel cell 1 includes at least 2 single cells 1 provided with an anode plate, a membrane electrode, and a cathode plate, and the single cells 1 are sealed and stacked to form the fuel cell stack, preferably, in this embodiment, the frame width of the outer periphery of the fuel cell stack for sealing is in a range of 3-10mm, preferably 4-6 mm; the anode plate 10 and the cathode plate 30 according to this embodiment may be made of silicon plate, graphite plate, metal plate, ceramic plate, composite plate, or other suitable materials;

in the present embodiment, the inner peripheries of the surfaces of the anode plate 10 and the cathode plate 30 in each single cell 1 are respectively provided with an active region for arranging a reducing agent channel (a known structure, not shown) and an oxidizing agent channel (a known structure, not shown), the active regions are in contact with the membrane electrode 20, the anode plate 10, the cathode plate 30 and the membrane electrode frame 20a are sealed and pressed, the outer peripheries of at least 1 surface of the anode plate 10 and/or the cathode plate 30 and/or the membrane electrode frame 20a at least comprise a first closed sealant track and a second closed sealant track, and the first closed sealant track and the second closed sealant track are distributed in parallel or non-parallel intervals for realizing multiple sealing effects on the single cell 1;

preferably, in the present embodiment, the outer peripheries of the upper and lower surfaces of the anode plate 10 and the cathode plate 30 each include at least a first closed sealant lane and a second closed sealant lane, and further preferably, in the present embodiment, the first closed sealant lane and the second closed sealant lane on the upper and lower surfaces of each of the

anode plates

10,30 are distributed vertically and symmetrically with respect to the

bipolar plates

10,30, so as to achieve good sealing of the interiors of the single cells 1, and the anode plates 10 and the cathode plates 30 in adjacent single cells 1 can also achieve press-fitting sealing through the first closed sealant lane and the second closed sealant lane which are correspondingly matched, and meanwhile, the closed sealant lane structure distributed vertically and symmetrically with respect to the

anode plates

10,30 can reduce the shear stress generated to the

plates

10,30 when the single cells 1 are press-fitted, and further avoid the

plates

10,30 are deformed and damaged during pressing; of course, in other embodiments, at least the first closed sealant lane and the second closed sealant lane may be included in the outer peripheries of the upper and lower surfaces of the membrane electrode frame 20a, which is further favorable for the sealing effect;

in other embodiments, a bipolar plate that can be used as both the anode plate 10 and the cathode plate 30 may be used, and the inner peripheries of the upper and lower surfaces of the bipolar plate are respectively provided with active regions for disposing a reducing agent channel and an oxidizing agent channel; the outer peripheries of the upper surface and the lower surface of the bipolar plate at least comprise a first closed sealant line channel and a second closed sealant line channel, and the first closed sealant line channel and the second closed sealant line channel on the upper surface and the lower surface of the bipolar plate are vertically and symmetrically distributed relative to the bipolar plate; further preferably, the bipolar plate structure may adopt the related art solution disclosed in CN 110581288A.

Preferably, in the present embodiment, a preset closed sealant lane shape is used as a target pattern, and the sealant is disposed on the outer peripheries of the surfaces of the anode plate 10 and the cathode plate 30 by a screen printing process or an inkjet printing or a glue applying process or a brushing process, as further shown in fig. 2, the sealant end portion 40 on the surfaces of the

plates

10,30 is in a convex arc shape, and then the closed sealant lane is obtained by curing molding, so as to ensure that the closed sealant lane does not have a significant convex sense relative to the surfaces of the

plates

10, 30; since the screen printing process, the inkjet printing process, the glue applying process and the painting process are all known processes, a person skilled in the art can implement the conventional technical means according to a target pattern, and the embodiment does not have a technical scheme which is particularly required to be limited, so that the specific glue applying process is not described in detail in the embodiment; it should be further noted that the sealant used in the application can be any known sealant, and the application has no particular innovation in the sealant material itself, and the skilled person can select the sealant conventionally according to the actual requirement;

more preferably, in the present embodiment, the sealant is printed by a screen printing process, and in actual implementation, a target pattern of the screen printing plate is designed in advance by drawing software, and the thickness of the screen printing plate is selected according to the sealant track thickness required by the engineering design of fuel cell stack assembly, so as to print the sealant on the

electrode plates

10 and 30, or print the corresponding sealant on the membrane electrode frame 20 a;

preferably, in the present embodiment, before the sealant is cured and molded, the anode plate 10, the membrane electrode 20, the membrane electrode frame 20a and the cathode plate 30 are pressed into a whole in advance, and then the whole curing and sealing are performed, which may be referred to as wet sealing; in other embodiments, after the sealant is cured and molded, the anode plate 10, the membrane electrode 20, the membrane electrode frame 20a and the cathode plate 30 may be sealed and pressed into a whole, which may be referred to as dry sealing; the applicant finds that wet sealing has better performance on the sealing and bonding performances of two surfaces, has low requirement on the smoothness of the sealing surface and higher tolerance on the thickness difference of the sealing glue, but a fuel cell stack prepared by the wet sealing cannot be disassembled, the curing temperature is not too high, and the subsequent disassembly and assembly maintenance is not facilitated; relatively, the fuel cell stack prepared by dry sealing can be flexibly disassembled, and the sealant can be cured at a higher temperature before pressing and sealing, so that a higher curing degree is ensured; those skilled in the art can make specific selections according to actual needs, and this embodiment is not particularly limited in this respect;

preferably, in the present embodiment, the surfaces of the anode plate 10 and the cathode plate 30 may have surface undulations (not shown) as a rough feature structure, which facilitates the firm adhesion between each glue line and the surface of the

plates

10,30, and the height of the surface undulations is less than the height of the closed seal glue line channel; further preferably, the surface relief height is 0.01-0.5 times the height of the closed sealant lane, most preferably, the surface relief height is 0.1-0.3 times the height of the closed sealant lane;

the present embodiment preferably proposes the plates 10,30 (which may be used as anode plates or cathode plates), and the number of the closed sealant lines on the periphery of each surface of the

plates

10,30 is 2-300, preferably 2-20, and more preferably 4-10; specifically, preferably, as shown in fig. 3 and fig. 4, in the present embodiment, 4 closed sealant channels are disposed on the periphery of a single surface of the

electrode plates

10 and 30 at intervals, and specifically include a first closed sealant channel 41a, a second closed sealant channel 41b, a third closed sealant channel 41c, and a fourth closed sealant channel 41d, where the first closed sealant channel 41a is located on the outermost periphery, and the fourth closed sealant channel 41d is located on the periphery of the fluid channel;

specifically, the closed sealant lanes 41a, 41b, 41c, and 41d are preferably in a quadrilateral shape, and in other embodiments, the shape of the closed sealant lanes may be selected according to the shape and area of the actual electrode plates 10 and 30, for example, a triangular shape, an arc shape, or a closed shape with other shapes may be adopted, which is not particularly limited in this embodiment; the width W1 of each closed sealant lane 41a, 41b, 41c, 41d is in the range of 50-500 microns, preferably 50-250 microns, and most preferably 100 microns; the height range of each closed sealant track 41a, 41b, 41c, 41d is 5-100 micrometers, preferably 10-40 micrometers, and the most preferred embodiment is 30 micrometers, and the aspect ratio of each closed sealant track is 0.1-1, preferably 0.2-0.6, which is found by the applicant after a large number of tests, generally, as long as the width W1 of each sealant track 41a, 41b, 41c, 41d is two times larger than the height, the thickness of the intersection point between each closed sealant track is not increased, which is beneficial to obtaining more excellent sealing effect; the spacing period W2 of each closed sealant track 41a, 41b, 41c, 41d is in the range of 50-1000 microns, preferably 100-500 microns, and most preferably 300 microns, and the spacing period W2 referred to in this embodiment is the sum of the width W1 of the sealant track and the distance between adjacent sealant tracks.

Example 2: the remaining technical solutions of this embodiment 2 are the same as those of embodiment 1, except that, referring to fig. 5 and fig. 6, in this embodiment 2, a plurality of seal partition glue lines 50a (located at two sides of the inlet/outlet 60 of the polar plate fluid channel) are disposed between adjacent closed seal glue lines, and two ends of each seal partition glue line 50a are respectively connected to 1 closed seal glue line, which is beneficial to further sealing effect.

Example 3: the remaining technical solutions of this embodiment 3 are the same as those of embodiment 1 or embodiment 2, except that, referring to fig. 7, in this embodiment 3, a plurality of seal partition glue lines 50b (located at two sides not provided with the fluid passage inlet/outlet 60) are disposed between adjacent closed sealant lines, and two ends of each seal partition glue line 50b are respectively connected to 1 closed sealant line; the interval D1 of the sealing and separating glue line 50b is in the range of 150-; particularly preferably, the sealing partition glue lines 50b between different adjacent closed sealing glue lines are distributed in a flush manner, which is beneficial to further sealing effect.

Example 4: the remaining technical solutions of this embodiment 4 are the same as those of embodiment 3, except that, referring to fig. 8, in this embodiment 4, a plurality of seal partition glue lines 50c are disposed between adjacent closed sealant lanes, and both ends of each seal partition glue line 50c are respectively connected to 1 closed sealant lane; the sealing partition glue lines 50c between different adjacent closed sealing glue lines are distributed in a staggered manner, which is beneficial to further sealing effect.

Example 5: the remaining technical solutions of this embodiment 5 are the same as those of embodiment 1, and the difference is that, referring to fig. 9 and fig. 10, this embodiment 5 provides a polar plate (which can be used as an anode plate or a cathode plate), the outer periphery of a single surface of the polar plate is provided with 2 closed sealant lanes, specifically including a first closed sealant lane 42a and a second closed sealant lane 42b, the first closed sealant lane 42a is located at the outer periphery of the second closed sealant lane 42b, wherein, the distance between the first closed sealant line channel 42a and the second closed sealant line channel 42b in the long side direction is not equal to the distance between the two in the wide side direction, therefore, the first closed sealant line channel and the second closed sealant line channel are distributed at intervals in a non-parallel mode, and the sealant lines in the first closed sealant line channel and the second closed sealant line channel are not overlapped.

Example 6: the remaining technical solutions of this embodiment 6 are the same as that of embodiment 1, and the difference is that, referring to fig. 11 and fig. 12, this embodiment 6 provides a polar plate (which may be used as an anode plate or a cathode plate), where the periphery of a single surface of the polar plate is provided with 4 closed sealant lanes, specifically including a first closed sealant lane 43a, a second closed sealant lane 43b, a third closed sealant lane 43c, and a fourth closed sealant lane 43d, where the first closed sealant lane 43a, the second closed sealant lane 43b, the third closed sealant lane 43c, and the fourth closed sealant lane 43d are distributed at non-parallel intervals, and part of the first closed sealant lane 43a, the second closed sealant lane 43b, and the third closed sealant lane 43c are overlapped.

It should be noted that, as well known to those skilled in the art, in order to realize the injection and outflow of fluid (reducing agent fluid, oxidant fluid or cooling medium fluid), the periphery of the

electrode plates

10,30 of the fuel cell stack generally needs to be provided with a plurality of fluid channel inlets and outlets 60, preferably, in order to further facilitate the sealing effect, except for the fluid channel inlets and outlets which need to be correspondingly communicated with the fluid channels provided by themselves, the peripheries of the other fluid channel inlets and outlets (communicated with the fluid channel inlets and outlets of other electrode plates) of the

electrode plates

10,30 are all sealed by providing a plurality of sealing glue lines (refer to the sealing and separating glue lines 50a) connected with the closed sealing glue lines, the membrane electrode frame 20a can also be correspondingly provided with reference to the sealing structure, and the embodiment will not be specifically described.

The embodiments 1-6 creatively provide a plurality of closed sealing glue lines on the outer periphery of the surface of the pole plate, which has the following positive technical effects compared with the prior art that a sealing mode of sealing a gasket or beating a circle of gasket is adopted: because the multiple sealing effect on the single fuel cell is realized, the leakage probability possibly caused by a single sealing rubber line is greatly reduced; in practical application, the leakage probability of the structure with n closed sealant lines is n times of the leakage probability of a single sealant, so that the leakage probability of the fuel cell is obviously reduced; the embodiment further provides that the sealing and separating rubber lines are arranged between the adjacent spaced closed sealing rubber lines, so that the leakage probability of the fuel cell can be further reduced through separating in different regions (for example, when a polar plate is scratched, in the process of screen printing, the height of the rubber line at each point is defective due to the blockage of the screen at each point, and the total leakage probability can be reduced by separating the rubber lines through the accidental quality defects); the printed or brushed glue line can be very thin and can be flush with the surface of the polar plate as much as possible, so that gaps between the polar plates in the fuel cell and gaps between the polar plates and a membrane electrode frame are greatly reduced, and the sealing performance of a single glue line is effectively improved; the structure of avoiding adopting seal ring (need not set up groove structure), on the basis of guaranteeing excellent sealed effect, be favorable to reducing the thickness, volume and the weight of single cell in the fuel cell, consequently can promote the power density of fuel cell pile powerfully.

The theoretical knowledge level of combining this application inventor and based on make a large amount of experimental verification to this application sealed effect after summarize the discovery, in the structural scheme of multichannel sealed gluey line that this application provided, influence sealed effect's main factor including: the number of the closed sealant lanes, the height of the closed sealant lanes, the width W1 of the closed sealant lanes, the interval period W2 of each closed sealant lane, the distance D1 of the sealing partition sealant line (if any) and the parameter design of the excessive or insufficient width of the sealing partition sealant line all have negative effects on the sealing effect or other performances; the surface relief height (smoothness) of the surface of the polar plate is also a factor influencing the sealing effect, and particularly, scratches and pits on the surface of the polar plate can be caused in the processing process of the polar plate, so that a leakage channel is formed between sealing parts; therefore, the present application lists more preferable parameter ranges in the embodiments, and those skilled in the art can further perform experiments to find out the optimal relevant parameter settings according to the description of the present application, and these parameter ranges are all routine technical choices that those skilled in the art can make according to the content of the present application and the technical teaching given by the present application, and the detailed description is not repeated for the sake of brevity.

In order to further verify the sealing effect of the embodiment, the application performs a comparative test:

first set of comparative examples: by adopting the technical scheme of the embodiment 1, the number of the closed sealant lines is 2;

second set of comparative examples: by adopting the technical scheme of the embodiment 1, the number of the closed sealant lines is 4;

third set of comparative examples: by adopting the technical scheme of the embodiment 2, the number of the closed sealant lines is 4;

fourth comparative example: the fuel cell stack was constructed as in example 1, except that the plates were sealed by a one-pass rubber ring.

According to the sealing structure of the four groups of comparative examples, the fuel cell stacks with 2 monocells are obtained by sealing and pressing, the fuel cell stacks are connected with compressed air, the air pressure of the compressed air can be continuously adjusted and measured within the range of 0-0.7MPa, the fuel cell stacks are immersed in water, whether bubbles exist or not is observed to verify air leakage, and then the sealing effect is verified, and the specific observation process is as follows:

when compressed air was not injected into each fuel cell stack, no bubbling was found;

when compressed air with a pressure of 0.1MPa was injected into each fuel cell stack, no bubbling was observed;

when compressed air at a pressure of 0.2MPa was injected into each fuel cell stack, the fuel cell stacks of the fourth comparative example exhibited very little bubbling, and no bubbling was observed in the remaining stacks;

when compressed air with a pressure of 0.3MPa was injected into each fuel cell stack, the fuel cell stacks of the fourth comparative example exhibited more bubbling, and the remaining stacks exhibited no bubbling;

when compressed air having a pressure of 0.4MPa was injected into each fuel cell stack, the fuel cell stacks of the fourth comparative example exhibited a large amount of bubbling, the fuel cell stacks of the first comparative example exhibited a very small amount of bubbling, and the remaining stacks exhibited no bubbling.

When compressed air having a pressure of 0.5MPa was injected into each fuel cell stack, the fuel cell stacks of the fourth comparative example failed in the overall seal, the fuel cell stacks of the first comparative example exhibited a small amount of bubbling, and the remaining stacks exhibited no bubbling.

The fuel cell stack without air leakage in the test can reach the air leakage standard specified by the national standard GB/T28817-2012 and the international standard IEC/TS 62282-7-12010.

In the actual production of a fuel cell stack, the pressure of the fluid inside it is usually 0.3MPa at maximum, so there is no risk of leakage as long as the gas leakage threshold pressure of the stack is ensured to be greater than 0.3 MPa.

Of course, the present application only exemplifies some embodiments, and those skilled in the art can select different numbers and shapes of the closed sealant lines and the sealant partition lines according to actual needs to obtain a large number of alternative embodiments, and the changes of these alternative embodiments can bring positive technical effects on the sealing effect, and also belong to the conventional technical choices that can be made by those skilled in the art based on the technical content of the present application, so that the present application will not be further described.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. The utility model provides a seal structure of fuel cell pile, the fuel cell pile includes 1 at least monocell that is equipped with anode plate, membrane electrode and negative plate, and the anode plate in every monocell and negative plate surface inner periphery are equipped with the active area that is used for setting up reductant passageway and oxidant passageway respectively, and this active area contacts with the membrane electrode, just sealed pressfitting between anode plate, negative plate and the membrane electrode frame, its characterized in that, the outer periphery of 1 at least surface of anode plate and/or negative plate and/or membrane electrode includes first closed form sealed glue line way and second closed form sealed glue line way at least, first closed form sealed glue line way with the second closed form sealed glue line way is parallel interval distribution or non-parallel interval distribution, is used for realizing to the multiple sealed effect of monocell.

2. The sealing structure of a fuel cell stack according to claim 1, wherein the outer peripheries of the upper and lower surfaces of the anode plate and/or the cathode plate and/or the membrane electrode each include at least a first closed sealant lane and a second closed sealant lane, and the first closed sealant lane and the second closed sealant lane of the upper and lower surfaces of each plate or membrane electrode are vertically and symmetrically distributed with respect to the bipolar plate or membrane electrode.

3. A sealing structure of a fuel cell stack according to claim 1, wherein 1 or more sealing and isolating adhesive lines are disposed at intervals between adjacent closed sealing adhesive lines, and both ends of the sealing and isolating adhesive line are respectively connected to 1 closed sealing adhesive line.

4. The seal structure of a fuel cell stack according to claim 1, 2 or 3, wherein a predetermined closed seal sealant lane shape is used as a target pattern, a seal sealant is disposed on an outer periphery of a surface of the anode plate or the cathode plate or the membrane electrode by a screen printing process or an ink jet printing or a glue applying process or a painting process, and the closed seal sealant lane is obtained by curing molding.

5. A seal structure of a fuel cell stack according to claim 4, wherein the end of the sealant on the surface of the electrode plate or the membrane electrode is in the shape of a convex arc.

6. The seal structure of a fuel cell stack according to claim 4, wherein the anode plate, the membrane electrode frame and the cathode plate are previously pressed together before the sealant is cured and molded, and then the entire curing and sealing are performed.

7. The sealing structure of a fuel cell stack according to claim 4, wherein the anode plate, the membrane electrode frame and the cathode plate are sealed and pressed into a whole after the sealant is cured and molded.

8. A seal structure of a fuel cell stack according to claim 1, wherein the surface of the plate has surface undulations as a roughness feature to facilitate a secure bond between each glue line and the surface of the plate.

9. A seal structure of a fuel cell stack according to claim 8, wherein said surface relief height is smaller than the height of said closed sealant lane.

10. The seal structure of a fuel cell stack according to claim 1, wherein the number of the closed sealant lanes is 2 to 300, and/or the width of the closed sealant lanes is in the range of 30 to 500 micrometers, and/or the height of the closed sealant lanes is in the range of 3 to 100 micrometers, and/or the aspect ratio of each closed sealant lane is 0.1 to 1.