Hydrogen fuel cell stack

Abstract

The invention discloses a hydrogen fuel cell stack which comprises a pair of end plates, a plurality of cell units are stacked between the pair of end plates, each cell unit comprises a cathode plate and an anode plate, each end plate is provided with an end plate connecting hole, the cathode plate in each cell unit is provided with a cathode plate connecting hole, and the anode plate in each cell unit is provided with a cathode plate connecting hole. The anode plate in each battery unit is provided with an anode plate connecting hole, the end plate connecting hole corresponds to the cathode plate connecting hole of each cathode plate and the anode plate connecting hole of each anode plate, and the end plates and all the battery units are fixed through the end plate connecting holes, the cathode plate connecting holes and the anode plate connecting holes; an air flow field capable of spirally conveying air from inside to outside is arranged on the plate surface of each negative plate; and a hydrogen flow field capable of spirally conveying hydrogen from outside to inside is arranged on the plate surface of each anode plate. The method has the advantage that the condition that the middle of the polar plate is expanded and bulged due to uneven heating in the working process of the electric pile can be effectively prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen fuel cells. Background Art

[0002] A hydrogen fuel cell is an electrochemical device that converts the chemical energy of hydrogen into electrical energy. It has been developing rapidly in recent years because it is clean and pollution-free. The structure of a hydrogen fuel cell stack includes a pair of end plates, and a number of battery cells are stacked between the end plates, also known as single cells. Each single cell includes a cathode plate, an anode plate, and a proton exchange membrane. The cathode plate and the anode plate are processed with flow channels, also known as flow fields, which are used to separate oxidants and reductants, collect current, guide the reaction gas to be evenly distributed, conduct heat, and drain water.

[0003] In a conventional hydrogen fuel cell stack, the structure of the flow field on the plate includes: a plurality of straight or folded flow channels opened on the plate surface of the flow field plate, and the flow channels extend from one end of the plate surface of the flow field plate to the other end of the plate surface of the flow field. All the plates in the hydrogen fuel cell stack are fixed around the plate surface outside the flow field.

[0004] It has been found during use that traditional plates have the following defects: the hydrogen fuel cell stack expands due to heat during the reaction, and the center of the plate is prone to expansion due to uneven pressure and heat, which can easily lead to failure of the sealing of the entire hydrogen fuel cell stack. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a hydrogen fuel cell stack in which all the plates are fixed in the middle, which can effectively prevent the center of the plate from expanding due to uneven pressure and uneven heating, thereby effectively extending the service life of the hydrogen fuel cell stack.

[0006] In order to solve the above problems, the technical solution adopted by the present invention is: a hydrogen fuel cell stack, comprising: a pair of end plates, a plurality of battery cells are stacked between the pair of end plates, each battery cell comprises a cathode plate and an anode plate, each end plate is provided with an end plate connection hole, a cathode plate in each battery cell is provided with a cathode plate connection hole, an anode plate in each battery cell is provided with an anode plate connection hole, the end plate connection holes correspond to the cathode plate connection holes of each cathode plate and the anode plate connection holes of each anode plate, and the end plates and all battery cells are fixed through the end plate connection holes, the cathode plate connection holes and the anode plate connection holes; An air flow field capable of conveying air spirally from the inside to the outside is arranged on the surface of each cathode plate; an arc-shaped air flow channel inlet is arranged on the cathode plate at the air flow field inlet, an arc-shaped air flow channel outlet is arranged on the cathode plate at the air flow field outlet, and a cathode plate air output hole is arranged on the cathode plate outside the air flow channel outlet; the cathode plate connection hole on each cathode plate is located at the spiral center of the air flow field thereon, and fan-shaped cathode plate air input holes and fan-shaped cathode plate hydrogen output holes are arranged on the cathode plates on both sides of the cathode plate connection hole, the air flow channel inlet is located outside the cathode plate air input hole, and the air flow field is arranged spirally from the inside to the outside in the direction from the air flow channel inlet to the air flow field outlet; a cathode plate hydrogen input hole is also arranged on each cathode plate; A hydrogen flow field capable of spirally transporting hydrogen from outside to inside is arranged on the surface of each anode plate; an arc-shaped hydrogen flow channel inlet is arranged on the anode plate at the hydrogen flow field inlet, an arc-shaped hydrogen flow channel outlet is arranged on the anode plate at the hydrogen flow field outlet, and an anode plate hydrogen input hole is arranged on the anode plate outside the hydrogen flow channel inlet; the anode plate connection hole on each anode plate is located at the spiral center of its hydrogen flow field, and fan-shaped anode plate air input holes and fan-shaped anode plate hydrogen output holes are arranged on the anode plates on both sides of the anode plate connection hole, and the hydrogen flow channel outlet is located outside the anode plate hydrogen output hole, and the hydrogen flow field is spirally arranged from outside to inside in the direction from the hydrogen flow channel inlet to the hydrogen flow channel outlet; an anode plate air output hole is also arranged on each anode plate; The two end plates are respectively a working end plate and a support end plate, wherein the working end plate is provided with an end plate air input hole, an end plate air output hole, an end plate hydrogen input hole, and an end plate hydrogen output hole, which are sealed and connected with the cathode plate air input hole, cathode plate air output hole, cathode plate hydrogen input hole, cathode plate hydrogen output hole on the cathode plate in each battery unit, and the anode plate air input hole, anode plate air output hole, anode plate hydrogen input hole, and anode plate hydrogen output hole on the anode plate, so as to form a stack air input channel, a stack air output channel, a stack hydrogen input channel, and a stack hydrogen output channel, respectively, the air flow channel inlet on each cathode plate is connected with the stack air input channel, and the air flow channel outlet on each cathode plate is connected with the stack air output channel; the hydrogen flow channel inlet on each anode plate is connected with the stack hydrogen input channel, and the hydrogen flow channel outlet on each anode plate is connected with the stack hydrogen output channel.

[0007] Furthermore, in the aforementioned hydrogen fuel cell stack, a side connection mechanism is also arranged between a pair of end plates and all battery cells, and the side connection mechanism includes: a plurality of end plate positioning holes are opened on each end plate, at least two cathode plate positioning holes are opened on the cathode plate in each battery cell, each cathode plate positioning hole is opened on the edge of the cathode plate outside the air flow field, and all cathode plate positioning holes are evenly distributed on both sides of the longitudinal center axis of the cathode plate; a plurality of anode plate positioning holes are opened on the anode plate in each battery cell, each anode plate positioning hole is opened on the edge of the anode plate outside the hydrogen flow field, and all anode plate positioning holes are evenly distributed on both sides of the longitudinal center axis of the anode plate; all end plate positioning holes correspond one-to-one with all cathode plate positioning holes on each cathode plate, and all anode plate positioning holes on each anode, and are fixed by positioning pins.

[0008] Furthermore, in the aforementioned hydrogen fuel cell stack, the end plate connection holes of a pair of end plates are fixed to the cathode plate connection holes and anode plate connection holes of all battery cells by bolts.

[0009] Furthermore, in the aforementioned hydrogen fuel cell stack, each end plate has an outer wall provided with reinforcing ribs centered on the end plate connection hole and in a cross shape, and the thickness of the reinforcing ribs gradually increases from the edge of the end plate toward the end plate connection hole.

[0010] Furthermore, in the aforementioned hydrogen fuel cell stack, an end plate water inlet and an end plate water outlet are provided on the working end plate, a cathode plate water inlet and a cathode plate water outlet are provided on each cathode plate, and an anode plate water inlet and an anode plate water outlet are provided on each anode plate; the end plate water inlet and the end plate water outlet on the working end plate are respectively sealed and connected with the cathode plate water inlet and the cathode plate water outlet on each cathode plate and the anode plate water inlet and the anode plate water outlet on each anode plate to form a stack water input channel and a stack water output channel; a water flow field for cooling is provided on the other side of the anode plate of each battery cell, and the water flow field includes: a water flow field inlet and a water flow field outlet, and a A plurality of water flow field channel ridges are provided, and water flow channels are formed between adjacent water flow field channel ridges, and the water flow channels guide water from the water flow field inlet to the water flow field outlet; the water flow channels are distributed in the area corresponding to the position of the hydrogen flow field, and the water flow channels are arranged in a mirror-symmetrical manner about the longitudinal center axis of the anode plate; the end plate water inlet and the end plate water outlet on the working end plate are arranged in a mirror-symmetrical manner about the longitudinal center axis of the working end plate, the cathode plate water inlet and the cathode plate water outlet on the cathode plate are arranged in a mirror-symmetrical manner about the longitudinal center axis of the cathode plate, and the anode plate water inlet and the anode plate water outlet on the anode plate are arranged in a mirror-symmetrical manner about the longitudinal center axis of the anode plate; the water flow field inlet and the water flow field outlet of each anode plate are respectively connected to the stack water input channel and the stack water output channel.

[0011] Furthermore, in the aforementioned hydrogen fuel cell stack, the air flow field structure on each cathode plate includes: a plurality of spiral and spaced cathode flow channel ridges protruding from the cathode plate surface, there are at least two cathode flow channel ridges, each cathode flow channel ridge is arranged in an Archimedean spiral from the inside to the outside, and a cathode flow channel is formed between every two adjacent cathode flow channel ridges; the starting ends of all cathode flow channel ridges are staggered in the circular arc-shaped air flow channel inlet position area, and the ends of all cathode flow channel ridges are also staggered in the circular arc-shaped air flow channel outlet position area.

[0012] Furthermore, in the aforementioned hydrogen fuel cell stack, a cathode flow channel ridge starting end position area is provided with a plurality of spaced starting end auxiliary air flow channel ridge segments for separating the airflow and guiding the airflow to the air flow channel inlet, the starting end auxiliary air flow channel ridge segments are arranged in the same spiral spacing as the cathode flow channel ridges outside thereof, and a cathode flow channel ridge terminal position area is provided with a plurality of spaced terminal auxiliary air flow channel ridge segments for separating the airflow and guiding the airflow to the air flow channel outlet, the terminal auxiliary air flow channel ridge segments are arranged in the same spiral spacing as the cathode flow channel ridges inside thereof.

[0013] Furthermore, in the aforementioned hydrogen fuel cell stack, the number of cathode flow channel ridges is four.

[0014] Furthermore, in the aforementioned hydrogen fuel cell stack, the hydrogen flow field structure on each anode plate includes: a plurality of spiral and spaced anode flow channel ridges protruding from the anode plate surface, the number of anode flow channel ridges being at least two, each anode flow channel ridge being arranged in an Archimedean spiral from the outside to the inside, and an anode flow channel being formed between every two adjacent anode flow channel ridges; the starting ends of the anode flow channel ridges are staggered in the circular arc-shaped hydrogen flow channel inlet position area, and the ends of all the anode flow channel ridges are also staggered in the circular arc-shaped hydrogen flow channel outlet position area.

[0015] Furthermore, in the aforementioned hydrogen fuel cell stack, a starting end position area of ​​the anode flow channel ridge is provided with a plurality of spaced starting end auxiliary hydrogen flow channel ridge segments for separating the gas flow and guiding the gas flow to the hydrogen flow channel inlet, the starting end auxiliary hydrogen flow channel ridge segments are arranged in the same spiral spacing as the anode flow channel ridge on its inner side, and a terminal position area of ​​the anode flow channel ridge is provided with a plurality of spaced terminal auxiliary hydrogen flow channel ridge segments for separating the gas flow and guiding the gas flow to the hydrogen flow channel outlet, the terminal auxiliary hydrogen flow channel ridge segments are arranged in the same spiral spacing as the anode flow channel ridge on its outer side.

[0016] Furthermore, in the aforementioned hydrogen fuel cell stack, the number of anode flow channel ridges is four.

[0017] Furthermore, in the aforementioned hydrogen fuel cell stack, the four corners of each end plate and the cathode plate and anode plate are rounded.

[0018] The advantages of the present invention are: First, it adopts an intermediate fixing method so that the middle position area of ​​the electrode plate is also constrained, which can effectively prevent the expansion and bulging of the middle of the electrode plate due to uneven heating during the operation of the entire stack, thereby greatly extending the service life of the stack. Second, based on the intermediate fixation, the air flow field on the cathode plate and the hydrogen flow field on the anode plate are both spirally arranged, thereby providing a new type of spiral flow field structure. The spiral flow field structure has a tendency to throw the gas out along the spiral direction, which can not only accelerate the diffusion of the gas, but also disturb the gas, thereby increasing the contact between the gas and the diffusion layer, greatly improving the reaction efficiency, and thus greatly improving the working efficiency of the hydrogen fuel cell stack. Third, both the air flow field and the hydrogen flow field adopt a multi-head spiral flow channel structure, which greatly improves the distribution speed of the gas and can effectively reduce the pressure difference between the gas inlet and outlet, thereby greatly improving the working efficiency of the stack and reducing the failure rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of a hydrogen fuel cell stack described in the present invention.

[0020] Figure 2 It is a structural schematic diagram of the air flow field on the cathode plate in a hydrogen fuel cell stack described in the present invention.

[0021] Figure 3 It is a structural schematic diagram of the hydrogen flow field on the anode plate in a hydrogen fuel cell stack described in the present invention.

[0022] Figure 4 It is a structural schematic diagram of the water flow field on the anode plate in a hydrogen fuel cell stack described in the present invention. DETAILED DESCRIPTION

[0023] The present invention will be further described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0024] like Figure 1As shown, a hydrogen fuel cell stack includes: a pair of end plates, two end plates are respectively a working end plate 1 and a support end plate 2, and a plurality of battery cells are stacked between the pair of end plates, each battery cell includes a cathode plate 3 and an anode plate 4. An end plate connection hole 11 is provided on each end plate. A cathode plate connection hole 301 is provided on the cathode plate 3 in each battery cell, and an anode plate connection hole 401 is provided on the anode plate 4 in each battery cell. The end plate connection hole 11 corresponds to the cathode plate connection hole 301 of each cathode plate 3 and the anode plate connection hole 401 of each anode plate 4. A pair of end plates and all battery cells are fixed by the end plate connection hole 11, the cathode plate connection hole 301 and the anode plate connection hole 401. Specifically, in this embodiment, the end plate connection hole 11 of a pair of end plates is fixed to the cathode plate connection hole 301 and the anode plate connection hole 401 of all battery cells by bolts 5. In order to increase the rigidity of a pair of end plates and further improve the reliability of the connection, a cross-shaped reinforcing rib 18 centered on the end plate connecting hole 11 is provided on the outer wall of each end plate, and the thickness of the reinforcing rib 18 gradually increases from the edge of the end plate toward the end plate connecting hole 11.

[0025] like Figure 2 As shown, an air flow field 30 capable of conveying air spirally from the inside to the outside is arranged on the plate surface of each cathode plate 3; an air flow channel inlet 31 is opened on the cathode plate 3 at the entrance of the air flow field 30, an air flow channel outlet 32 ​​is opened on the cathode plate 3 at the outlet of the air flow field 30, and a cathode plate air output hole 302 is opened on the cathode plate 3 outside the air flow channel outlet 32. The air flow channel inlet 31 and the air flow channel outlet 32 ​​are both arc-shaped. The cathode plate connection hole 301 on each cathode plate 3 is located at the spiral center of the air flow field 30 thereon. Fan-shaped cathode plate air input holes 303 and fan-shaped cathode plate hydrogen output holes 304 are opened on the cathode plate 3 on both sides of the cathode plate connection hole 301. The air flow channel inlet 31 is located outside the cathode plate air input hole 303, and the air flow field 30 is spirally arranged from the inside to the outside in the direction from the air flow channel inlet 31 to the air flow channel outlet 32. A cathode plate hydrogen input hole 305 is also arranged on each cathode plate 3. The air channel inlet 31, the air channel outlet 32, the cathode plate air output hole 302, and the cathode plate air input hole 303 are located on the same side of the cathode plate longitudinal center axis XX, and the cathode plate hydrogen output hole 304 and the cathode plate hydrogen input hole 305 are located on the other side of the cathode plate longitudinal center axis XX.

[0026] In this embodiment, the structure of the air flow field 30 on each cathode plate 3 includes: a plurality of spiral cathode flow channel ridges protruding from the plate surface of the cathode plate 3 and arranged at intervals, and there are at least two cathode flow channel ridges. In this embodiment, the number of cathode flow channel ridges is four, such as Figure 2As shown, the four cathode flow channel ridges are respectively the first cathode flow channel ridge 33, the second cathode flow channel ridge 34, the third cathode flow channel ridge 35, and the fourth cathode flow channel ridge 36. Each cathode flow channel ridge is arranged in an Archimedean spiral from the inside to the outside, and a cathode flow channel 37 is formed between each two adjacent cathode flow channel ridges. The purpose of providing multiple cathode flow channel ridges is to form a multi-start spiral cathode flow channel 37 so that the gas at the air flow channel inlet 31 can be quickly dispersed to reduce the pressure difference between the air flow channel inlet 31 and the air flow channel outlet 32.

[0027] In order to allow the gas to be quickly and evenly dispersed from the air channel inlet 31 to each cathode channel 37, the starting ends of all cathode channel ridges are staggered in the arc-shaped air channel inlet 31. In order to allow the gas in each cathode channel 37 to be quickly and evenly dispersed to the air channel outlet 32, the ends of all cathode channel ridges are also staggered in the arc-shaped air channel outlet 32.

[0028] The cathode flow channel ridge starting position area is provided with a plurality of spaced starting auxiliary air flow channel ridge segments 38 for separating the airflow and guiding the airflow to the air flow channel inlet 31. Specifically, in this embodiment, two starting auxiliary air flow channel ridge segments 38 are provided, one long and one short. The starting auxiliary air flow channel ridge segment 38 is arranged in the same spiral spacing as the cathode flow channel ridge outside it. The cathode flow channel ridge terminal position area is provided with a plurality of spaced terminal auxiliary air flow channel ridge segments 39 for separating the airflow and guiding the airflow to the air flow channel outlet 32. The terminal auxiliary air flow channel ridge segment 39 is arranged in the same spiral spacing as the cathode flow channel ridge inside it.

[0029] like Figure 3As shown, a hydrogen flow field 40 capable of spirally transporting hydrogen from outside to inside is provided on the plate surface of each anode plate 4; a hydrogen flow channel inlet 41 is provided on the anode plate 4 at the inlet of the hydrogen flow field 40, and the hydrogen flow channel inlet 41 is in the shape of a circular arc. A hydrogen flow channel outlet 42 is provided on the anode plate 4 at the outlet of the hydrogen flow field 40, and the hydrogen flow channel outlet 42 is also in the shape of a circular arc. An anode plate hydrogen input hole 405 is provided on the anode plate 4 outside the hydrogen flow channel inlet 41. The anode plate connection hole 401 on each anode plate 4 is located at the spiral center of its hydrogen flow field 40. A fan-shaped anode plate air input hole 403 and a fan-shaped anode plate hydrogen output hole 404 are provided on the anode plate 4 on both sides of the anode plate connection hole 401. The hydrogen flow channel outlet 42 is located outside the anode plate hydrogen output hole 404. The hydrogen flow field 40 is spirally arranged from outside to inside in the direction from the hydrogen flow channel inlet 41 to the hydrogen flow channel outlet 42. Each anode plate 4 is also provided with an anode plate air output hole 402. The hydrogen flow channel inlet 41, the hydrogen flow channel outlet 42, the anode plate hydrogen output hole 404, and the anode plate hydrogen input hole 405 are located on the same side of the longitudinal center axis OO of the anode plate; the anode plate air input hole 403 and the anode plate air output hole 402 are located together on the other side of the longitudinal center axis OO of the anode plate.

[0030] In this embodiment, the hydrogen flow field 40 structure on each anode plate 4 includes: a plurality of spiral anode flow ridges protruding from the surface of the anode plate 4 and arranged at intervals, each anode flow ridge being arranged in an Archimedean spiral shape from outside to inside. There are at least two anode flow ridges, and in this embodiment, the number of anode flow ridges is four. Figure 3 As shown, the four anode flow channel ridges are respectively the first anode flow channel ridge 43, the second anode flow channel ridge 44, the third anode flow channel ridge 45, and the fourth cathode flow channel ridge 36, and an anode flow channel 47 is formed between each two adjacent anode flow channel ridges. The starting ends of the anode flow channel ridges are staggered in the position area of ​​the arc-shaped hydrogen flow channel inlet 41, which can make the hydrogen in the hydrogen flow channel inlet 41 evenly and quickly distributed to each anode flow channel 47. The ends of all the anode flow channel ridges are also staggered in the position area of ​​the arc-shaped hydrogen flow channel outlet 42, which can make the hydrogen in all the anode flow channels 47 quickly discharged into the hydrogen flow channel outlet 42.

[0031] In the present embodiment, the starting end position area of ​​the anode flow channel ridge is provided with a plurality of spaced starting end auxiliary hydrogen flow channel ridge segments 48 for separating the gas flow and guiding the gas flow to the hydrogen flow channel inlet 41, and the starting end auxiliary hydrogen flow channel ridge segments 48 are arranged in the same spiral spacing as the anode flow channel ridge inside thereof, and the terminal position area of ​​the anode flow channel ridge is provided with a plurality of spaced terminal auxiliary hydrogen flow channel ridge segments 49 for separating the gas flow and guiding the gas flow to the hydrogen flow channel outlet 42, and the terminal auxiliary hydrogen flow channel ridge segments 49 are arranged in the same spiral spacing as the anode flow channel ridge outside thereof.

[0032] The working end plate 1 is also provided with an end plate air input hole 13, an end plate air output hole 12, an end plate hydrogen input hole 15, and an end plate hydrogen output hole 14. The end plate air input hole 13, the end plate air output hole 12, the end plate hydrogen input hole 15, and the end plate hydrogen output hole 14 are respectively provided on the plate body on both sides of the longitudinal center axis of the working end plate 1.

[0033] The end plate air input hole 13, the end plate air output hole 12, the end plate hydrogen input hole 15, and the end plate hydrogen output hole 14 are sealed and connected with the cathode plate air input hole 303, the cathode plate air output hole 302, the cathode plate hydrogen input hole 305, and the cathode plate hydrogen output hole 304 on the cathode plate 3 in each battery cell, and the anode plate air input hole 403, the anode plate air output hole 402, the anode plate hydrogen input hole 405, and the anode plate hydrogen output hole 404 on the anode plate 4, thereby forming a stack air input channel 300, a stack air output channel 200, a stack hydrogen input channel 500, and a stack hydrogen output channel 400, respectively. The air flow channel inlet 31 on each cathode plate 3 is connected to the stack air input channel 300; the air flow channel outlet 32 ​​on each cathode plate 3 is connected to the stack air output channel 200; the hydrogen flow channel inlet 41 on each anode plate 4 is connected to the stack hydrogen input channel 500, and the hydrogen flow channel outlet 42 on each anode plate 4 is connected to the stack hydrogen output channel 400.

[0034] When the hydrogen fuel cell stack is working, air enters the stack air input channel 300 from the end plate air input hole 13, and then is distributed to each cathode flow channel 37 through the air flow channel inlet 31 of each cathode plate 3. Under the guidance of the cathode flow channel 37, the remaining air converges to the air flow channel outlet 32, and then is discharged from the hydrogen fuel cell stack from the end plate air output hole 12 through the stack air output channel 200.

[0035] Hydrogen enters the stack hydrogen input channel 500 from the end plate hydrogen input hole 15, and is then distributed to each anode channel 47 through the hydrogen channel inlet 41 of each anode plate 4. Under the guidance of the anode channel 47, the remaining hydrogen converges to the hydrogen channel outlet 42, and then is discharged from the hydrogen fuel cell stack from the end plate hydrogen output hole 14 through the stack hydrogen output channel 400.

[0036] In order to cool down the hydrogen fuel cell stack during operation, the working end plate 1 is also provided with an end plate water inlet 16 and an end plate water outlet 17. Each cathode plate 3 is also provided with a cathode plate water inlet 306 and a cathode plate water outlet 307; each anode plate 4 is also provided with an anode plate water inlet 406 and an anode plate water outlet 407. The end plate water inlet 16 and the end plate water outlet 17 on the working end plate are sealed and connected with the cathode plate water inlet 306 and the cathode plate water outlet 307 on each cathode plate 3 and the anode plate water inlet 406 and the anode plate water outlet 407 on each anode plate 4, respectively, one by one, to form a stack water input channel 600 and a stack water output channel 700.

[0037] like Figure 4 As shown, a water flow field 50 for cooling is arranged on the other side of the anode plate 4 of each battery unit, and the water flow field 50 includes: a water flow field inlet 51 and a water flow field outlet 52, and a plurality of water flow field flow channel ridges 53 are arranged between the water flow field inlet 51 and the water flow field outlet 52, and a water flow channel 54 is formed between adjacent water flow field flow channel ridges 53, and the water flow channel 54 guides water from the water flow field inlet 51 to the water flow field outlet 52. The water flow channels are distributed in the area corresponding to the position of the hydrogen flow field 40, and the water flow channels 54 are arranged in a mirror symmetric manner about the longitudinal center axis OO of the anode plate. The end plate water inlet 16 and the end plate water outlet 17 on the working end plate 1 are mirror-symmetrically arranged about the longitudinal center axis of the working end plate 1, the cathode plate water inlet 306 and the cathode plate water outlet 307 on the cathode plate 3 are mirror-symmetrically arranged about the longitudinal center axis XX of the cathode plate, and the anode plate water inlet 406 and the anode plate water outlet 407 on the anode plate 4 are mirror-symmetrically arranged about the longitudinal center axis OO of the anode plate; the water flow field inlet 51 of the water flow field 50 of each anode plate 4 is connected to the fuel cell water input channel 600, and the water flow field outlet 52 of the water flow field 50 of each anode plate 4 is connected to the fuel cell water output channel 700.

[0038] During operation, cooling water enters the stack water input channel 600 from the end plate water inlet 16, and then enters the water flow field 50 on each anode plate 4. The cooling water in the water flow field 50 continuously absorbs heat during the movement from the water flow field inlet 51 to the water flow field outlet 52. The heated cooling water converges to the stack water output channel 700, and then is output from the end plate water outlet 17. The above is the water cooling process.

[0039] For further reliable assembly and connection, a hydrogen fuel cell stack described in this embodiment is also provided with a side connection mechanism, the structure of which includes: a plurality of end plate positioning holes 19 are provided on each end plate; at least two cathode plate positioning holes 309 are provided on the cathode plate 3 in each battery unit, each cathode plate positioning hole 309 is provided at the edge of the cathode plate 3 outside the air flow field 30, and all cathode plate positioning holes 309 are evenly distributed on both sides of the longitudinal center axis XX of the cathode plate. A plurality of anode plate positioning holes 409 are provided on the anode plate 4 in each battery unit, each anode plate positioning hole 409 is provided at the edge of the anode plate 4 outside the hydrogen flow field 40, and all anode plate positioning holes 409 are evenly distributed on both sides of the longitudinal center axis OO of the anode plate. All end plate positioning holes 19 correspond to all cathode plate positioning holes 309 on each cathode plate 3, and all anode plate positioning holes 409 on each anode plate 4, and are fixed by positioning pins. In addition, the four corners of each end plate, cathode plate and anode plate are rounded to facilitate transportation and installation.

[0040] The above-mentioned hydrogen fuel cell stack has the following advantages: First, it adopts the middle fixing method, which makes the middle position area of ​​the electrode plate also constrained, so as to effectively prevent the expansion and bulging of the middle of the electrode plate due to uneven heating during the operation of the entire stack, thereby greatly extending the service life of the stack. Second, based on the middle fixation, the air flow field on the cathode plate and the hydrogen flow field on the anode plate are both spirally arranged, thereby providing a new type of spiral flow field structure. The spiral flow field structure has a tendency to throw the gas out along the spiral direction, which can not only accelerate the diffusion of the gas, but also disturb the gas, thereby increasing the contact between the gas and the diffusion layer, greatly improving the reaction efficiency, and thus greatly improving the working efficiency of the hydrogen fuel cell stack. Third, both the air flow field and the hydrogen flow field adopt a multi-head spiral flow channel structure, which further greatly improves the distribution speed of the gas and can effectively reduce the pressure difference between the gas inlet and outlet, thereby greatly improving the working efficiency of the stack and reducing the failure rate.

Claims

1. A hydrogen fuel cell stack, comprising: A pair of end plates, a plurality of battery cells are stacked between the pair of end plates, each battery cell includes a cathode plate and an anode plate, characterized in that: an end plate connection hole is provided on each end plate, a cathode plate connection hole is provided on the cathode plate in each battery cell, an anode plate connection hole is provided on the anode plate in each battery cell, the end plate connection holes correspond to the cathode plate connection holes of each cathode plate and the anode plate connection holes of each anode plate, and the end plates and all battery cells are fixed through the end plate connection holes, the cathode plate connection holes and the anode plate connection holes; An air flow field capable of conveying air spirally from the inside to the outside is arranged on the surface of each cathode plate; an arc-shaped air flow channel inlet is arranged on the cathode plate at the air flow field inlet, an arc-shaped air flow channel outlet is arranged on the cathode plate at the air flow field outlet, and a cathode plate air output hole is arranged on the cathode plate outside the air flow channel outlet; the cathode plate connection hole on each cathode plate is located at the spiral center of the air flow field thereon, and fan-shaped cathode plate air input holes and fan-shaped cathode plate hydrogen output holes are arranged on the cathode plates on both sides of the cathode plate connection hole, the air flow channel inlet is located outside the cathode plate air input hole, and the air flow field is arranged spirally from the inside to the outside in the direction from the air flow channel inlet to the air flow field outlet; a cathode plate hydrogen input hole is also arranged on each cathode plate; A hydrogen flow field capable of spirally transporting hydrogen from outside to inside is arranged on the surface of each anode plate; an arc-shaped hydrogen flow channel inlet is arranged on the anode plate at the hydrogen flow field inlet, an arc-shaped hydrogen flow channel outlet is arranged on the anode plate at the hydrogen flow field outlet, and an anode plate hydrogen input hole is arranged on the anode plate outside the hydrogen flow channel inlet; the anode plate connection hole on each anode plate is located at the spiral center of its hydrogen flow field, and fan-shaped anode plate air input holes and fan-shaped anode plate hydrogen output holes are arranged on the anode plates on both sides of the anode plate connection hole, and the hydrogen flow channel outlet is located outside the anode plate hydrogen output hole, and the hydrogen flow field is spirally arranged from outside to inside in the direction from the hydrogen flow channel inlet to the hydrogen flow channel outlet; an anode plate air output hole is also arranged on each anode plate; The two end plates are respectively a working end plate and a support end plate, wherein the working end plate is provided with an end plate air input hole, an end plate air output hole, an end plate hydrogen input hole, and an end plate hydrogen output hole, which are sealed and connected with the cathode plate air input hole, cathode plate air output hole, cathode plate hydrogen input hole, cathode plate hydrogen output hole on the cathode plate in each battery unit, and the anode plate air input hole, anode plate air output hole, anode plate hydrogen input hole, and anode plate hydrogen output hole on the anode plate, so as to form a stack air input channel, a stack air output channel, a stack hydrogen input channel, and a stack hydrogen output channel, respectively, the air flow channel inlet on each cathode plate is connected with the stack air input channel, and the air flow channel outlet on each cathode plate is connected with the stack air output channel; the hydrogen flow channel inlet on each anode plate is connected with the stack hydrogen input channel, and the hydrogen flow channel outlet on each anode plate is connected with the stack hydrogen output channel.

2. A hydrogen fuel cell stack according to claim 1, characterized in that: A side connection mechanism is also arranged between a pair of end plates and all battery cells, and the side connection mechanism includes: a plurality of end plate positioning holes are arranged on each end plate, at least two cathode plate positioning holes are arranged on the cathode plate in each battery cell, each cathode plate positioning hole is arranged at the edge of the cathode plate outside the air flow field, and all cathode plate positioning holes are evenly distributed on both sides of the longitudinal center axis of the cathode plate; a plurality of anode plate positioning holes are arranged on the anode plate in each battery cell, each anode plate positioning hole is arranged at the edge of the anode plate outside the hydrogen flow field, and all anode plate positioning holes are evenly distributed on both sides of the longitudinal center axis of the anode plate; all end plate positioning holes correspond one-to-one with all cathode plate positioning holes on each cathode plate and all anode plate positioning holes on each anode, and are fixed by positioning pins.

3. A hydrogen fuel cell stack according to claim 1 or 2, characterized in that: The end plate connection holes of a pair of end plates are fixed to the cathode plate connection holes and anode plate connection holes of all battery cells by bolts.

4. A hydrogen fuel cell stack according to claim 1 or 2, characterized in that: The outer wall of each end plate is provided with reinforcing ribs in a cross shape with the end plate connection hole as the center, and the thickness of the reinforcing ribs gradually increases from the edge of the end plate to the end plate connection hole.

5. A hydrogen fuel cell stack according to claim 1 or 2, characterized in that: The working end plate is also provided with an end plate water inlet and an end plate water outlet, each cathode plate is also provided with a cathode plate water inlet and a cathode plate water outlet, and each anode plate is also provided with an anode plate water inlet and an anode plate water outlet; the end plate water inlet and the end plate water outlet on the working end plate are respectively sealed and connected with the cathode plate water inlet and the cathode plate water outlet on each cathode plate and the anode plate water inlet and the anode plate water outlet on each anode plate in a one-to-one correspondence to form a stack water input channel and a stack water output channel; A water flow field for cooling is arranged on the other side of the anode plate of each battery cell, and the water flow field includes: a water flow field inlet and a water flow field outlet, a plurality of water flow field flow channel ridges are arranged between the water flow field inlet and the water flow field outlet, and water flow channels are formed between adjacent water flow field flow channel ridges, and the water flow channels guide water from the water flow field inlet to the water flow field outlet; the water flow channels are distributed in the area corresponding to the position of the hydrogen flow field, and the water flow channels are arranged in a mirror-symmetrical manner about the longitudinal center axis of the anode plate; the end plate water inlet and the end plate water outlet on the working end plate are arranged in a mirror-symmetrical manner about the longitudinal center axis of the working end plate, the cathode plate water inlet and the cathode plate water outlet on the cathode plate are arranged in a mirror-symmetrical manner about the longitudinal center axis of the cathode plate, and the anode plate water inlet and the anode plate water outlet on the anode plate are arranged in a mirror-symmetrical manner about the longitudinal center axis of the anode plate; the water flow field inlet and the water flow field outlet of the water flow field of each anode plate are respectively connected to the stack water input channel and the stack water output channel.

6. A hydrogen fuel cell stack according to claim 1 or 2, characterized in that: The air flow field structure on each cathode plate includes: a plurality of spiral cathode flow channel ridges protruding from the cathode plate surface and arranged at intervals, there are at least two cathode flow channel ridges, each cathode flow channel ridge is arranged in an Archimedean spiral from the inside to the outside, and a cathode flow channel is formed between every two adjacent cathode flow channel ridges; the starting ends of all cathode flow channel ridges are staggered in the circular arc-shaped air flow channel inlet position area, and the ending ends of all cathode flow channel ridges are also staggered in the circular arc-shaped air flow channel outlet position area.

7. A hydrogen fuel cell stack according to claim 6, characterized in that: The cathode flow channel ridge starting end position area is provided with a plurality of spaced starting end auxiliary air flow channel ridge segments for separating the airflow and guiding the airflow to the air flow channel inlet, and the starting end auxiliary air flow channel ridge segments are arranged in the same spiral spacing as the cathode flow channel ridge on its outside, and the cathode flow channel ridge terminal position area is provided with a plurality of spaced terminal auxiliary air flow channel ridge segments for separating the airflow and guiding the airflow to the air flow channel outlet, and the terminal auxiliary air flow channel ridge segments are arranged in the same spiral spacing as the cathode flow channel ridge on its inside.

8. A hydrogen fuel cell stack according to claim 5, characterized in that: The number of cathode flow channel ridges is four.

9. A hydrogen fuel cell stack according to claim 1 or 2, characterized in that: The hydrogen flow field structure on each anode plate includes: a plurality of spiral anode flow channel ridges protruding from the anode plate surface and arranged at intervals, there are at least two anode flow channel ridges, each anode flow channel ridge is arranged in an Archimedean spiral from the outside to the inside, and an anode flow channel is formed between every two adjacent anode flow channel ridges; the starting ends of the anode flow channel ridges are staggered in the circular arc-shaped hydrogen flow channel inlet position area, and the ends of all the anode flow channel ridges are also staggered in the circular arc-shaped hydrogen flow channel outlet position area.

10. A hydrogen fuel cell stack according to claim 9, characterized in that: The starting end position area of ​​the anode flow channel ridge is provided with a plurality of spaced starting end auxiliary hydrogen flow channel ridge segments for separating the gas flow and guiding the gas flow to the hydrogen flow channel inlet, and the starting end auxiliary hydrogen flow channel ridge segments are arranged in the same spiral spacing as the anode flow channel ridge inside thereof, and the terminal position area of ​​the anode flow channel ridge is provided with a plurality of spaced terminal auxiliary hydrogen flow channel ridge segments for separating the gas flow and guiding the gas flow to the hydrogen flow channel outlet, and the terminal auxiliary hydrogen flow channel ridge segments are arranged in the same spiral spacing as the anode flow channel ridge outside thereof.

11. A hydrogen fuel cell stack according to claim 9, characterized in that: The number of anode flow channel ridges is four.

12. A hydrogen fuel cell stack according to claim 9, characterized in that: The four corners of each end plate, cathode plate and anode plate are rounded.

Images