Fuel cell assembly, press-fitting equipment and press-fitting method

Abstract

The invention relates to a fuel cell assembly, press-fitting equipment and a press-fitting method.The fuel cell assembly comprises a reactor core structure, the reactor core structure comprises a first reactor core structure and a second reactor core structure, the first reactor core structure is provided with a first reactor core flow channel, and the second reactor core structure is provided with a second reactor core flow channel; the end plate structures comprise a first end plate structure, a middle end plate structure and a second end plate structure, the first reactor core structure is arranged between the first end plate structure and the middle end plate structure, and the second reactor core structure is arranged between the second reactor core structure and the middle end plate structure; the middle end plate structure is provided with an air inlet channel and an air outlet channel, the air inlet channel is communicated with the first reactor core runner and the second reactor core runner, and the air outlet channel is communicated with the first reactor core runner and the second reactor core runner. According to the technical scheme, the problem that in the prior art, the voltage consistency of the fuel cell becomes poor due to the fact that the middle of a galvanic pile collapses is effectively solved.

Description

Technical Field

[0001] The present application relates to the technical field of fuel cells, and in particular to a fuel cell assembly, a press-assembly device and a press-assembly method. Background Art

[0002] A fuel cell is a highly efficient energy conversion and power generation device that uses hydrogen as the best fuel and directly converts the chemical energy in the fuel and oxidant into electrical energy through electrochemical reactions without going through a combustion process. It does not go through a thermal engine process and is not limited by the Carnot cycle, and its actual energy conversion efficiency is as high as 50% to 80%. Proton exchange membrane fuel cells are the fifth generation of fuel cells developed after alkaline fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, and solid oxide fuel cells. They have the characteristics of low operating temperature, short start-up time, high power density, fast load response, and no electrolyte loss.

[0003] There are many factors that affect the voltage consistency of a single fuel cell, one of the main factors is the packaging structure design of the fuel cell stack. How to reasonably and evenly apply the packaging load to each single cell component of the stack is an important issue that needs to be solved. Uniformity has two meanings. First, for a single cell, the packaging pressure acting on the activation area should be kept as consistent as possible. The better the consistency, the more uniform the reaction in each area of ​​the single cell; secondly, the packaging pressure between each single cell should be kept as consistent as possible, so that the contact pressure between the bipolar plate and the membrane electrode of each single cell is similar, and the porosity of the gas diffusion layer of each single cell is close, so as to ensure the transmission consistency of the reaction substances of each single cell, and thus keep the voltage of the single cell at the same level.

[0004] like Figure 1 As shown, a large number of studies and experiments have shown that there is a difference between the packaging pressure of a single cell close to the end plate and the packaging pressure of a single cell in the middle of the stack 1, which is manifested as the packaging pressure on the side close to the end plate is greater than the packaging pressure in the middle, and with the increase in the number of stacked single cell layers, the packaging pressure in the middle of the stack 1 tends to decrease; that is, a large number of stacked single cells will deteriorate the structural stiffness of the stack, and when encountering severe working conditions such as vibration and impact, the middle of the stack will experience a "collapse" phenomenon, especially interlayer slippage between local single cells along the Z-direction impact direction, which may cause leakage due to sealing failure, as well as inconsistent mass transfer efficiency due to inconsistent contact pressure inside each single cell assembly, thereby deteriorating the voltage consistency of the single cell. Summary of the invention

[0005] The present application provides a fuel cell assembly, a press-fitting device and a press-fitting method to solve the problem in the prior art that the voltage consistency of the fuel cell is deteriorated due to the "collapse" in the middle of the fuel cell stack.

[0006] A fuel cell component provided according to the present application includes: a core structure, the core structure includes a first core structure and a second core structure, the first core structure is provided with a first core flow channel, and the second core structure is provided with a second core flow channel; an end plate structure, the end plate structure includes a first end plate structure, an intermediate end plate structure and a second end plate structure, the first core structure is arranged between the first end plate structure and the intermediate end plate structure, and the second core structure is arranged between the second core structure and the intermediate end plate structure; the intermediate end plate structure has an air inlet channel and an air outlet channel, the air inlet channel is communicated with both the first core flow channel and the second core flow channel, and the air outlet channel is communicated with both the first core flow channel and the second core flow channel; a fixing structure, the fixing structure includes a first fixing structure and a second fixing structure, the first fixing structure connects the first end plate structure and the intermediate end plate structure, and the second fixing structure connects the second end plate structure and the intermediate end plate structure; an electrical lead structure, the electrical lead structure is electrically connected to both the first core structure and the second core structure.

[0007] Further, the air inlet channel is arranged at the first end of the intermediate end plate structure, the air outlet channel is arranged at the second end of the intermediate end plate structure, the air inlet channel includes a first air inlet channel and a second air inlet channel, the air outlet channel includes a first air outlet channel and a second air outlet channel, the first air inlet channel is communicated with the first core flow channel, the second air inlet channel is communicated with the second core flow channel, the first air outlet channel is communicated with the first core flow channel, and the second air outlet channel is communicated with the second core flow channel.

[0008] Further, the air inlet channel includes a first air inlet section and a second air inlet section communicated with the first air inlet section, the first air inlet section extends along a first direction, the second air inlet section extends along a second direction, a chamfer is provided at the connection of the first air inlet section and the second air inlet section, and the outlet of the second air inlet section is communicated with the flow channel of the core structure.

[0009] Further, in the direction from the connection of the second air inlet section and the first air inlet section to the outlet of the second air inlet section, the outlet of the second air inlet section is a reduced opening with a gradually decreasing cross-sectional area, and the inclination angle is between 2° and 10°.

[0010] Further, the first fixing structure includes a plurality of first fixing tie rods, the second fixing structure includes a plurality of second fixing tie rods, both ends of the plurality of first fixing tie rods are connected to the first end plate structure and the intermediate end plate structure through fasteners respectively, and both ends of the plurality of second fixing tie rods are connected to the second end plate structure and the intermediate end plate structure through fasteners respectively.

[0011] Further, the electrical lead structure includes a first current collector plate, a second current collector plate, a connecting copper bar, a third current collector plate, a fourth current collector plate, a first lead-out copper bar, and a second lead-out copper bar. The first current collector plate is disposed between the middle end plate structure and the first core structure. The second current collector plate is disposed between the first core structure and the first end plate structure. Both ends of the connecting copper bar are electrically connected to the first current collector plate and the second current collector plate. The third current collector plate is disposed between the second core structure and the middle end plate structure. The first end of the first lead-out copper bar is electrically connected to the first current collector plate. The fourth current collector plate is disposed between the second core structure and the second end plate structure. The first end of the second lead-out copper bar is electrically connected to the fourth current collector plate.

[0012] Further, the fuel cell assembly further includes a first elastic member, a first insulating plate, a second elastic member, and a second insulating plate. The first insulating plate is located between the second current collector plate and the first end plate structure. The first elastic member is located between the first insulating plate and the first end plate structure, and the first elastic member is elastically abutted against the first insulating plate and the first end plate structure. The second insulating plate is located between the fourth current collector plate and the second end plate structure. The second elastic member is located between the second insulating plate and the second end plate structure, and the second elastic member is elastically abutted against the second insulating plate and the second end plate structure.

[0013] Further, the fuel cell assembly further includes a voltage sampling structure, and the voltage sampling structure is connected to the bipolar plate of the core structure.

[0014] According to another aspect of the present application, there is also provided a pressing device for a fuel cell assembly. The pressing device for the fuel cell assembly is used to press the above-mentioned fuel cell assembly. The pressing device includes: a base structure, the base structure includes a base, a support frame, and an upper platform. The bottom of the support frame is connected to the base, and the upper platform is located above the support frame; a lifting seat structure, the lifting seat structure is disposed on the base; a flipping and clamping structure, the flipping and clamping structure is disposed on the support frame; a pressing structure, the pressing structure is installed on the upper platform. The pressing structure, the lifting seat structure, and the clamping part of the flipping and clamping structure are correspondingly arranged in the vertical direction.

[0015] Further, the flipping and clamping structure includes a driving part, a first clamping arm, and a second clamping arm. The support frame includes a first support column and a second support column. The first clamping arm is rotatably disposed on the first support column, the second clamping arm is rotatably disposed on the second support column, the driving part is fixed on the first support column, and the output end of the driving part is connected to the first clamping arm.

[0016] Furthermore, the first clamping arm includes a first spline, a bearing, a clamping seat, a telescopic rod and a clamping arm, the driving part includes a servo motor and a second spline connected to the output shaft of the servo motor, the first spline has a through hole, the inner wall of the first spline is a spline structure, the inner wall of the first spline is adapted to the outer wall of the second spline, the outer wall of the first spline matches the inner ring of the bearing, the outer ring of the bearing is fixed on the first supporting column, the clamping seat is connected to the second spline, the telescopic rod is fixed on the clamping seat, and the clamping arm is connected to the telescopic rod.

[0017] According to another aspect of the present application, a press-fitting method for a fuel cell assembly is also provided. The press-fitting method adopts the above-mentioned press-fitting equipment, and the press-fitting method includes the following steps: starting the flip clamping structure to clamp the middle end plate structure; starting the pressing structure to press-fit the first core structure; after the pressing is completed, the pressing structure returns to the initial position; starting the flip clamping structure to flip 180 degrees; starting the pressing structure to press-fit the second core structure; after the pressing is completed, the pressing structure returns to the initial position; the flip clamping structure returns to the initial position.

[0018] By applying the technical solution of the present application, a first end plate structure and a second end plate structure are provided at both ends of the core structure, and an intermediate end plate structure is provided in the middle of the core structure, and the intermediate end plate structure divides the core structure into a first core structure and a second core structure. The intermediate end plate structure, the first end plate structure and the second end plate structure cooperate to support the core structure, thereby increasing the strength of the core structure and improving the phenomenon that the core structure is prone to "collapse". In addition, the intermediate end plate structure is provided with an air inlet channel and an air outlet channel, which greatly reduces the distance difference between the farthest path and the nearest path of the gas in the core structure, and improves the consistency of the voltage of a single cell in the fuel cell assembly. The technical solution of the present application effectively solves the problem of poor consistency of fuel cell voltage caused by the "collapse" of the middle part of the stack in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0021] Figure 1 A schematic diagram of a battery stack structure in the prior art is shown;

[0022] Figure 2 A schematic diagram of the three-dimensional structure of a fuel cell assembly according to the first embodiment of the present application is shown;

[0023] Figure 3 shows the Figure 2 explosion structure schematic diagram of the fuel cell assembly;

[0024] Figure 4 shows the Figure 2 gas flow path schematic diagram of the fuel cell assembly;

[0025] Figure 5 shows the Figure 2 three-dimensional structure schematic diagram of the intermediate end plate structure of the fuel cell assembly;

[0026] Figure 6 shows the Figure 5 front view schematic diagram of the intermediate end plate structure;

[0027] Figure 7 shows the Figure 6 A - A cross-sectional schematic diagram of the intermediate end plate structure;

[0028] Figure 8 shows the three-dimensional structure schematic diagram of the press-fitting device of the present application;

[0029] Figure 9 shows the Figure 8 explosion schematic diagram at position B of the press-fitting device;

[0030] Figure 10 shows the Figure 8 working state schematic diagram of the press-fitting device and the fuel cell assembly;

[0031] Figure 11 shows the process schematic diagram of the press-fitting method of the fuel cell of the present application.

[0032] Among them, the above-mentioned drawings include the following reference numerals:

[0033] 1. Stack; 10. Core structure; 11. First core structure; 12. Second core structure; 20. End plate structure; 21. First end plate structure; 22. Intermediate end plate structure; 221. Intake channel; 2211. First intake section; 2212. Second intake section; 222. Exhaust channel; 2221. First exhaust section; 2222. Second exhaust section; 23. Second end plate structure; 30. Base structure; 31. Base; 32. Support frame; 33. Upper platform; 40. Lifting seat structure; 50. Inverting and clamping structure; 51. Driving part; 52. First clamping arm; 521. First spline; 522. Bearing; 523. Clamping seat; 524. Telescopic rod; 525. Clamping part; 53. Second clamping arm; 60. Pressing structure; 70. Fixing structure; 71. First fixing structure; 711. First fixing tie rod; 72. Second fixing structure; 721. Second fixing tie rod; 80. Electrical lead structure; 81. First current collector plate; 82. Second current collector plate; 83. Connecting copper bar; 84. Third current collector plate; 85. Fourth current collector plate; 86. First lead-out copper bar; 87. Second lead-out copper bar; 91. First elastic member; 92. First insulating plate; 93. Second elastic member; 94. Second insulating plate; 95. Voltage sampling structure. Detailed implementation manners

[0034] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0035] It should be pointed out that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0036] For the sake of description, spatial relative terms such as "above...", "over...", "on the upper surface of...", "above" and the like may be used herein to describe the spatial position relationship of one device or feature to other devices or features as shown in the figures. It should be understood that the spatial relative terms are intended to cover different orientations in use or operation in addition to the orientation shown in the figures of the device. For example, if the device in the figure is inverted, the device described as "above other devices or structures" or "over other devices or structures" will then be positioned "below other devices or structures" or "under other devices or structures". Thus, the exemplary term "above..." may include both the orientation of "above..." and "below...". The device may also be positioned in other different ways, rotated 90 degrees or in other orientations, and corresponding explanations will be made to the spatial relative descriptions used herein.

[0037] AsFigures 2 to 7 As shown in the figure, the fuel cell assembly of the first embodiment includes: a stack core structure 10, an end plate structure 20, a fixing structure 70, and an electrical lead structure 80. The stack core structure 10 includes a first stack core structure 11 and a second stack core structure 12. The first stack core structure 11 is provided with a first stack core flow channel, and the second stack core structure 12 is provided with a second stack core flow channel. The end plate structure 20 includes a first end plate structure 21, an intermediate end plate structure 22, and a second end plate structure 23. The first stack core structure 11 is disposed between the first end plate structure 21 and the intermediate end plate structure 22, and the second stack core structure 12 is disposed between the second stack core structure 12 and the intermediate end plate structure 22. The intermediate end plate structure 22 has an intake channel 221 and an exhaust channel 222. The intake channel 221 is in communication with both the first stack core flow channel and the second stack core flow channel, and the exhaust channel 222 is in communication with both the first stack core flow channel and the second stack core flow channel. The fixing structure 70 includes a first fixing structure 71 and a second fixing structure 72. The first fixing structure 71 connects the first end plate structure 21 and the intermediate end plate structure 22, and the second fixing structure 72 connects the second end plate structure 23 and the intermediate end plate structure 22. The electrical lead structure 80 is electrically connected to both the first stack core structure 11 and the second stack core structure 12.

[0038] Applying the technical solution of the first embodiment, the first end plate structure 21 and the second end plate structure 23 are provided at both ends of the stack core structure 10, and the intermediate end plate structure 22 is provided in the middle of the stack core structure 10. The intermediate end plate structure 22 divides the stack core structure 10 into a first stack core structure 11 and a second stack core structure 12. The intermediate end plate structure 22, the first end plate structure 21, and the second end plate structure 23 cooperate to support the stack core structure 10 together, increasing the strength of the stack core structure 10 and improving the phenomenon that the stack core structure 10 is prone to "waist collapse". In addition, the intermediate end plate structure 22 is provided with an intake channel 221 and an exhaust channel 222, which greatly reduces the distance difference between the farthest path and the nearest path of the gas in the stack core structure 10 and improves the consistency of the single cell voltage in the fuel cell assembly. The technical solution of this embodiment effectively solves the problem of poor fuel cell voltage consistency caused by the "waist collapse" in the middle of the stack in the prior art.

[0039] It should be noted that the fixing structure 70 connects the fuel cell assembly into an integral structure. The electrical lead structure 80 serially leads out the electric quantity generated by the stack core structure 10.

[0040] Such as Figures 4 to 7As shown, in the technical solution of the first embodiment, the intake channel 221 is disposed at the first end of the intermediate end plate structure 22, and the outlet channel 222 is disposed at the second end of the intermediate end plate structure 22. The intake channel 221 includes a first intake channel and a second intake channel, and the outlet channel 222 includes a first outlet channel and a second outlet channel. The first intake channel communicates with the first core flow channel, the second intake channel communicates with the second core flow channel, the first outlet channel communicates with the first core flow channel, and the second outlet channel communicates with the second core flow channel. The above structure enables the first intake channel and the second intake channel to not interfere with each other, and the first outlet channel and the second outlet channel to not interfere with each other, making it easier to achieve the consistency of the voltages of each single cell. It should be noted that the first intake channel and the second intake channel are isolated by a partition, and the first outlet channel and the second outlet channel are isolated by a partition. From Figure 2 As seen from the left side, the three ports in the Z-axis direction are respectively an air flow channel (the first intake channel), a hydrogen flow channel, and a coolant flow channel, and the air flow channel, the hydrogen flow channel, and the coolant flow channel are isolated from each other. Similarly, the three ports in the Z-axis direction on the right side are symmetrically arranged with the three ports on the left side. The above partition and the intermediate end plate structure 22 are an integrally formed structure. In this embodiment, the fuel cell assembly is centrally symmetrically arranged in a plane along the first direction (Y-axis direction) of the intermediate end plate structure 22. The end face of the first end of the intermediate end plate structure 22 is the external manifold mating face. The fuel cell assembly further includes a tie rod structure that connects the first end plate structure 21, the intermediate end plate structure 22, and the second end plate structure 23, which will not be elaborated here.

[0041] As Figures 5 to 7 shown, the cross-sectional area of the first intake channel is designed, calculated, and tested according to the conditions of the flow channel.

[0042] As Figures 5 to 7As shown in the figure, in the technical solution of Embodiment 1, the intake passage 221 includes a first intake section 2211 and a second intake section 2212 connected to the first intake section 2211. The first intake section 2211 extends along the first direction (Y-axis direction), and the second intake section 2212 extends along the second direction (X-axis direction). There is a chamfer at the connection between the first intake section 2211 and the second intake section 2212, and the outlet of the second intake section 2212 is connected to the flow channel of the core structure 10. The first intake section 2211 extends along the first direction (Y-axis direction), and the second intake section 2212 extends along the second direction (X-axis direction), such a structure makes the setting of the core structure 10 more flexible. There is a chamfer at the connection between the first intake section 2211 and the second intake section 2212, and the outlet of the second intake section 2212 is connected to the flow channel of the core structure 10. The above chamfer setting reduces the fluid resistance on the one hand and plays a good role in guiding and directing the fluid on the other hand. It should be noted that the connection is an arc chamfer, which makes the fluid flow more smoothly and evenly, and further reduces the difference between each single cell during fluid supply.

[0043] As Figures 5 to 7 shown in the figure, in the technical solution of Embodiment 1, in the direction from the connection between the second intake section 2212 and the first intake section 2211 to the outlet of the second intake section 2212, the outlet of the second intake section 2212 is a reduced opening with a gradually decreasing cross-sectional area, and the inclination angle is between 2° and 10°. This is beneficial for the fluid to move towards the farther flow channels after entering the core structure 10, making the gas between each channel in the same core structure 10 (such as the first core structure 11) more uniform. The above fluid channel structure is designed according to the following formula:

[0044] In the prior art, as Figure 1 shown in the figure, in the "straight in and straight out" mode of the stack medium, "under-gassing" is likely to occur near the inlet position. In this patent, the medium turns 90 degrees to enter the stack, and an air flow guiding structure is set at the corner, which can not only achieve the purpose of smoothing the flow channel, but also fine-tune the air flow direction by adjusting the angle of the guiding structure, thereby achieving the purpose of balancing the flow rate between each single cell. When the medium exits the stack, a guiding structure is also set, and the back pressure of the stack can be adjusted by adjusting the guiding structure, further achieving the purpose of balancing the flow rate between each single cell.

[0045] In addition, this structure can improve the efficiency because it shortens the mixing length and reduces the fluid frictional resistance along the way.

[0046] Incompressible fluid Bernoulli equation:

[0047]

[0048] In the formula,

[0049] P 0 --- Atmospheric pressure;

[0050] ρ 0 --- Air density;

[0051] v 0 --- Air flow velocity in the atmosphere, v 0 = 0;

[0052] P 1 --- Outlet static pressure;

[0053] v 1 --- Outlet flow velocity;

[0054] · Total pressure loss ΔP:

[0055] ΔP = ∑h f + ∑h ξ

[0056] · Frictional resistance loss h f :

[0057]

[0058] · Local resistance loss h ξ :

[0059]

[0060] Wherein,

[0061] λ --- Frictional resistance coefficient;

[0062] ξ --- Inlet loss coefficient;

[0063] v --- Flow velocity of the medium in the pipeline;

[0064] G --- Mass flow rate of the medium;

[0065] D i --- Equivalent diameter of the pipeline;

[0066] ρ --- Density of the medium in the pipeline;

[0067] Ls --- Pipeline length

[0068] It should be noted that each first air inlet channel and each second air inlet channel both include the structure of the first air inlet section 2211 and the second air inlet section 2212. The cross-section of the outlet of the second air inlet section 2212 is adapted to the cross-section of the flow channel inlet of the core structure 10.

[0069] Such as Figures 5 to 7As shown, in the technical solution of Embodiment 1, the air outlet channel 222 includes a first air outlet section 2221 and a second air outlet section 2222 connected to the first air outlet section 2221. The first air outlet section 2221 extends along a first direction, and the second air outlet section 2222 extends along a second direction. The connection between the first air outlet section 2221 and the second air outlet section 2222 has a chamfer, and the inlet of the second air outlet section 2222 is connected to the flow channel outlet of the core structure 10. The chamfer here is also an arc chamfer, which makes the flow of the fluid smoother and more uniform, and further reduces the difference between individual single cells when the fluid passes through.

[0070] As Figure 7 shown, in the technical solution of Embodiment 1, in the direction from the connection between the second air outlet section 2222 and the first air outlet section 2221 to the outlet of the second air outlet section 2222, the outlet of the second air outlet section 2222 is a flared opening with a gradually increasing cross-sectional area, and the inclination angle is between 2° and 10°. Such a structure is also realized through the above theoretical formula derivation and simulation. It should be noted that the inner walls of the second air inlet section 2212 and the second air outlet section 2222 are gradually changing arc surfaces, so the above inclination angle changes, that is, the angle between the tangent direction of the arc surface and the first direction is a changing angle, and the angle change range is between 2° and 10°.

[0071] As Figure 2 and Figure 3 shown, in the technical solution of Embodiment 1, the first fixing structure 71 includes a plurality of first fixing tie rods 711, and the second fixing structure 72 includes a plurality of second fixing tie rods 721. Both ends of the plurality of first fixing tie rods 711 are connected to the first end plate structure 21 and the intermediate end plate structure 22 through fasteners, and both ends of the plurality of second fixing tie rods 721 are connected to the second end plate structure 23 and the intermediate end plate structure 22 through fasteners. The above structure is lightweight while playing a role in connection and fixation. Specifically, fixing grooves are provided on both sides of the first end plate structure 21, the intermediate end plate structure 22, and the second end plate structure 23 in the third direction Z, and the ends of the first fixing tie rods 711 and the ends of the second fixing tie rods 721 are both arranged in the fixing grooves.

[0072] As Figure 2 and Figure 3As shown, in the technical solution of the first embodiment, the electrical lead structure 80 includes a first current collector plate 81, a second current collector plate 82, a connecting copper bar 83, a third current collector plate 84, a fourth current collector plate 85, a first lead-out copper bar 86, and a second lead-out copper bar 87. The first current collector plate 81 is disposed between the middle end plate structure 22 and the first core structure 11. The second current collector plate 82 is disposed between the first core structure 11 and the first end plate structure 21. Both ends of the connecting copper bar 83 are electrically connected to the first current collector plate 81 and the second current collector plate 82. The third current collector plate 84 is disposed between the second core structure 12 and the middle end plate structure 22. The first end of the first lead-out copper bar 86 is electrically connected to the first current collector plate 81. The fourth current collector plate 85 is disposed between the second core structure 12 and the second end plate structure 23. The first end of the second lead-out copper bar 87 is electrically connected to the fourth current collector plate 85. The above structure facilitates the collection of the electric quantity of the fuel cell assembly together to provide electric energy for the outside. The second ends of the first lead-out copper bar 86 and the second lead-out copper bar 87 are both connected to the outside.

[0073] As Figure 2 and Figure 3 shown, in the technical solution of the first embodiment, the fuel cell assembly further includes a first elastic member 91, a first insulating plate 92, a second elastic member 93, and a second insulating plate 94. The first insulating plate 92 is located between the second current collector plate 82 and the first end plate structure 21. The first elastic member 91 is located between the first insulating plate 92 and the first end plate structure 21. The first elastic member 91 is elastically abutted against the first insulating plate 92 and the first end plate structure 21. The second insulating plate 94 is located between the fourth current collector plate 85 and the second end plate structure 23. The second elastic member 93 is located between the second insulating plate 94 and the second end plate structure 23. The second elastic member 93 is elastically abutted against the second insulating plate 94 and the second end plate structure 23. The arrangements of the first insulating plate 92 and the second insulating plate 94 insulate the core structure 10 from the outside. The arrangements of the first elastic member 91 and the second elastic member 93 enable the core structure 10 to have a good buffering effect. For example, when the fuel cell assembly receives an external force. In addition, due to the inherent properties of the material such as thermal expansion and contraction, the first elastic member 91 and the second elastic member 93 can also automatically adjust for thermal expansion and contraction. The structure in which the first elastic member 91, the first insulating plate 92, the second elastic member 93, and the second insulating plate 94 cooperate enables the core structure 10 to be more evenly stressed.

[0074] As Figure 2 and Figure 3 shown, in the technical solution of the first embodiment, the fuel cell assembly further includes a voltage sampling structure 95, and the voltage sampling structure 95 is connected to the bipolar plate of the core structure 10. The arrangement of the voltage sampling structure 95 is beneficial to monitoring each bipolar plate of the fuel cell assembly.

[0075] As can be seen from the above, the intermediate end plate structure 22 divides the core structure 10 into two equal parts along the X direction. The two sides share the intermediate end plate, and the same number of single cells are stacked on both sides. Each side uses a set of identical packaging components (including insulating plates, disc springs, gaskets, blind end plates, packaging straps, bolts) to apply the same packaging force for pressing. The current collectors and copper bars of the left and right cores (the first core structure 11 and the second core structure 12) are connected end to end to form a series structure.

[0076] The main functions of the intermediate end plate structure 22 are as follows:

[0077] 1) As a packaging end plate, it transmits the packaging pressure: The left and right cores are each locked with independent packaging straps, and the intermediate end plate structure 22 bears the pressure and transmits the packaging pressure to the core structure 10.

[0078] 2) The functions of fluid confluence and diversion: The intermediate end plate structure is designed with completely symmetric flow channels along the left and right in the X direction. The flow channel inlets and outlets connected to the outside are arranged on both sides of the intermediate end plate along the Y direction. The fluid enters the stack (core structure 10) after turning 90° in the end plate from the external inlet. The completely symmetric arrangement can ensure uniform diversion of the left and right cores during the working process, so as to keep the performance of the left and right stacks consistent. Since the number of single-cell stacks on one side is reduced and the length of the flow channel on one side is shortened, the fluid resistance can be reduced; in practical applications, the uniformity of the medium diversion of each single cell can be adjusted by adjusting the inclination angle of the flow channel entering the stack.

[0079] 3) Provide support for the middle area of the whole stack in the Z direction to avoid "waist collapse": Pressing support grooves are designed at the top and bottom (along the Z direction) of the intermediate end plate (intermediate end plate structure 22). One is to facilitate the support of the stack during pressing as a stack, and the other is that when the stack is assembled with the shell, positioning blocks need to be designed on the shell and embedded in the pressing support grooves of the intermediate end plate, so as to achieve the complete positioning of the stack. Due to the existence of the support structure during vibration and shock, "waist collapse" of the middle area of the whole stack can be avoided.

[0080] In addition, the intermediate end plate also has the following characteristics: Sealing grooves are designed on both the front and back sides (along the Y direction) of the intermediate end plate. When the stack is assembled with the shell, the mating surface of the external manifold needs to be exposed, and a gasket is used to seal between the stack shell and the intermediate end plate.

[0081] The intermediate end plate can be made of a low-ion-precipitation, low-moisture-absorption, high-temperature-resistant plastic with high strength and high rigidity, such as PPS-GF40, or an aluminum alloy plastic-coated material. Its structure should have sufficient strength and stiffness to avoid uneven stress inside the stack caused by deformation, which will in turn affect the performance of the whole stack.

[0082] Since the left and right cores are connected by an intermediate end plate, the core pressing steps are different from the current technical solution, and the stack press needs to be redesigned. On the basis of maintaining its pressing function, it should also have the function of turning the stack. Its structure is as follows (the gluing structure / positioning structure is not shown, and its structure is the same as that of the traditional press).

[0083] The insulating plate, single cell, blind end plate, disc spring, gasket, and current collector plate used in the fuel cell assembly all adopt the existing structures; the encapsulation force is the same as that of the existing structure. A new intermediate end plate is added, and a medium flow channel is integrated inside. The medium inlet and outlet are arranged laterally; a pressing support groove is designed on the end plate.

[0084] The intermediate end plate structure 20 divides the core into two parts, and each part uses a set of exactly the same encapsulation components to press the two cores. The number of encapsulation straps is doubled. Since the number of cores on one side is reduced, the length of the encapsulation strap is shorter than the existing scheme.

[0085] Reduces the risk of "waist collapse" in the Z direction in the middle of the stack during vibration and shock: realized by the combination of the intermediate end plate and the positioning block of the stack housing.

[0086] Reduces the medium pressure loss: Due to the adoption of the intermediate end plate structure, the number of single cells on one side is reduced, and then the length of the inlet pipeline on one side is reduced, so the medium pressure loss can be reduced.

[0087] Since the number of single cells on one side is reduced, the number of shunts from the inlet main pipe to the single cells on one side is reduced (for example, originally 1 divided by 350, now 1 divided by 175). By adjusting the inclination angle of the flow channel inlet, it is easier to achieve the uniformity of medium shunting between single cells.

[0088] The technical effect can be verified by analyzing and evaluating the displacement of the single cells in the middle of the stack of the new scheme and the existing scheme through vibration and shock simulation, or it can also be verified through the vibration and shock tests of the stack. By evaluating the consistency of the battery voltage and arranging displacement sensors in the single cell area in the middle of the stack to detect the Z-direction displacement of the single cells.

[0089] The actual pressure loss of the new scheme can be tested by the pressure loss test. The required equipment includes a flow bench, pressure sensors, temperature sensors, gas sources, stacks, manifolds, etc.

[0090] By testing the consistency of the stack voltage, the differences between the new scheme and the existing scheme are compared, and the consistency of the medium shunting of each single cell is evaluated.

[0091] Dividing the intermediate end plate into two symmetrical parts, independently encapsulating the left and right cores and then placing them opposite to each other, and connecting the two intermediate end plates with a fixed structure can also achieve the same effect, but how to connect the current collector plate and the copper bar needs to be further considered.

[0092] The technical solution of the second embodiment is different from that of the first embodiment in that there are multiple intermediate end plate structures 22, and the core structure 10 is divided into more than three parts. For example, there are two intermediate end plate structures 22, the core structure 10 is divided into four segments, and the end plates of the entire fuel cell assembly include five. In addition to the two intermediate end plate structures 22, there are also end plates at both ends and a central end plate. The fuel cell assembly of the second embodiment is symmetrically structured along the central end plate.

[0093] As Figures 8 to 10 shown, the present application also provides a press-fitting device for a fuel cell assembly. The press-fitting device for the fuel cell assembly is used to press-fit the above-mentioned fuel cell assembly. The press-fitting device includes: a base structure 30, a lifting seat structure 40, a flipping and clamping structure 50, and a pressing structure 60. The base structure 30 includes a base 31, a support frame 32, and an upper platform 33. The bottom of the support frame 32 is connected to the base 31, and the upper platform 33 is located above the support frame 32. The lifting seat structure 40 is arranged on the base 31. The flipping and clamping structure 50 is arranged on the support frame 32. The pressing structure 60 is installed on the upper platform 33. The pressing structure 60, the lifting seat structure 40, and the clamping part of the flipping and clamping structure 50 are correspondingly arranged in the vertical direction.

[0094] When the press-fitting device is in use, the flipping and clamping structure 50 clamps the fuel cell assembly to be assembled, and then the pressing structure 60 presses the fuel cell assembly to be assembled. After one side of the fuel cell assembly is assembled, the flipping and clamping structure 50 drives the fuel cell assembly to rotate a predetermined angle, and then the pressing structure 60 presses the other side of the fuel cell assembly to complete the assembly of the fuel cell assembly.

[0095] As Figures 8 to 10 shown, the flipping and clamping structure 50 of the press-fitting device of the present application includes a driving part 51, a first clamping arm 52, and a second clamping arm 53. The support frame 32 includes a first support column and a second support column. The first clamping arm 52 is rotatably arranged on the first support column, the second clamping arm 53 is rotatably arranged on the second support column, the driving part 51 is fixed on the first support column, and the output end of the driving part 51 is connected to the first clamping arm 52. The above structure is compact and easy to operate. By operating the driving part 51, the first clamping arm 52 rotates, and the first clamping arm 52 drives the second clamping arm 53 to rotate through the fuel cell assembly.

[0096] As Figure 9As shown, in the technical solution of the present application, the first clamping arm 52 includes a first spline 521, a bearing 522, a clamping seat 523, a telescopic rod 524 and a clamping portion 525, the driving portion 51 includes a servo motor and a second spline connected to the output shaft of the servo motor, the first spline 521 has a through hole, the inner wall of the first spline 521 is a spline structure, the inner wall of the first spline 521 is adapted to the outer wall of the second spline, the outer wall of the first spline 521 is matched with the inner ring of the bearing 522, the outer ring of the bearing 522 is fixed on the first supporting column, the clamping seat 523 is connected to the second spline, the telescopic rod 524 is fixed on the clamping seat 523, and the clamping portion 525 is connected to the telescopic rod 524. The output shaft of the servo motor is connected to the second spline, the second spline is matched with the first spline 521, and the structure of spline matching makes the transmission more stable, the transmission accuracy is higher, and the bearing capacity is stronger. The telescopic rod 524 can be a pneumatic telescopic rod, a hydraulic telescopic rod or an electric push rod. The clamping part 525 is a support rod (support claw).

[0097] From the above, it can be known that the press machine (packaging equipment) controls the moving direction of the pressing plate and the supporting claws through four electric cylinders or air cylinders on the top, bottom, left and right sides. When assembling the battery stack, first clamp the middle end plate on the lateral supporting claws (the clamping part 525 of the flip clamping structure 50), and completely fix the middle end plate through the left and right supporting claws, and provide support with the supporting claws on both sides to stack the single cells and other components. After the stacking is completed, the top cylinder applies pressure, and the top pressing plate applies the packaging pressure to the battery stack to move downward until the set pressing height of the battery stack is reached, and then the detection is carried out (there is a scale on the side frame). After one side is installed, press the servo motor activity button, and the servo motor drives the side supporting claws to rotate 180 degrees to flip the battery stack, and assemble the battery stack on the other side. The process is the same as before. The rotation angle can be monitored by the angle sensor installed on the servo motor. After the overall assembly is completed, press the bottom cylinder (the lifting cylinder of the lifting seat structure 40) activity button, and the bottom platform rises under the drive of the cylinder until the platform section contacts the bottom of the battery stack. Then press the side electric cylinder activity button to return the two side support claws to their initial positions. At this point, the battery stack is assembled as a whole and stands upright on the bottom platform. It can be removed manually and the next battery stack assembly can begin.

[0098] Figure 9 As shown, the composition of the rotating mechanism is demonstrated: the servo motor is fixed on the side frame (support frame 32), and its output shaft has splines, which cooperate with the splines welded on the lateral electric cylinder, so that the servo motor can drive the support claw to rotate, and the splines on the electric cylinder cooperate with the bearings, and the bearings are installed on the side frame. Therefore, the support claw can rotate while the frame does not move, and lip seals and sealing cover plates are used for internal sealing.

[0099] like Figure 11As shown, according to another aspect of the present application, a press-fitting method for a fuel cell assembly is further provided. The press-fitting method uses the above-mentioned press-fitting equipment, and the press-fitting method includes the following steps: Start the flipping and clamping structure 50 to clamp the intermediate end plate structure 22; Start the pressing structure 60 for press-fitting; After the press-fitting is completed, the pressing structure 60 returns to the initial position; Start the flipping and clamping structure 50 to flip 180 degrees; Start the pressing structure 60 for press-fitting; After the press-fitting is completed, the pressing structure 60 returns to the initial position; The flipping and clamping structure 50 returns to the initial position. The specific steps are as follows: Start the side electric cylinder, support the gripper to fix the intermediate end plate, assemble the stack, start the top surface cylinder for press-fitting and detection. Start the top surface cylinder, and the top surface pressing plate returns to the initial position. Start the servo motor to flip the stack 180 degrees, disassemble the lower stack, start the top surface cylinder for press-fitting and detection, start the top surface cylinder, the top surface pressing plate returns to the initial position, start the bottom surface cylinder, the bottom surface platform supports the entire stack, start the side electric cylinder, and the support claws return to the initial position.

[0100] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0101] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products, or devices.

[0102] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A fuel cell assembly, characterized in that, comprising: a core structure (10), the core structure (10) includes a first core structure (11) and a second core structure (12), the first core structure (11) is provided with a first core flow channel, and the second core structure (12) is provided with a second core flow channel; an end plate structure (20), the end plate structure (20) includes a first end plate structure (21), an intermediate end plate structure (22) and a second end plate structure (23), the first core structure (11) is disposed between the first end plate structure (21) and the intermediate end plate structure (22), and the second core structure (12) is disposed between the second core structure (12) and the intermediate end plate structure (22); the intermediate end plate structure (22) has an air inlet channel (221) and an air outlet channel (222), the air inlet channel (221) is in communication with both the first core flow channel and the second core flow channel, and the air outlet channel (222) is in communication with both the first core flow channel and the second core flow channel; a fixing structure (70), the fixing structure (70) includes a first fixing structure (71) and a second fixing structure (72), the first fixing structure (71) connects the first end plate structure (21) and the intermediate end plate structure (22), and the second fixing structure (72) connects the second end plate structure (23) and the intermediate end plate structure (22); an electrical lead structure (80), the electrical lead structure (80) is electrically connected to both the first core structure (11) and the second core structure (12).

2. The fuel cell assembly according to claim 1, characterized in that, the air inlet channel (221) is provided at a first end of the intermediate end plate structure (22), the air outlet channel (222) is provided at a second end of the intermediate end plate structure (22), the air inlet channel (221) includes a first air inlet channel and a second air inlet channel, the air outlet channel (222) includes a first air outlet channel and a second air outlet channel, the first air inlet channel is in communication with the first core flow channel, the second air inlet channel is in communication with the second core flow channel, the first air outlet channel is in communication with the first core flow channel, and the second air outlet channel is in communication with the second core flow channel.

3. The fuel cell assembly according to claim 1, characterized in that, the air inlet channel (221) includes a first air inlet section (2211) and a second air inlet section (2212) connected to the first air inlet section (2211), the first air inlet section (2211) extends in a first direction, the second air inlet section (2212) extends in a second direction, a chamfer is provided at the connection of the first air inlet section (2211) and the second air inlet section (2212), and the outlet of the second air inlet section (2212) is in communication with the flow channel of the core structure (10).

4. The fuel cell assembly according to claim 3, characterized in that, In the direction from the connection between the second intake section (2212) and the first intake section (2211) to the outlet of the second intake section (2212), the outlet of the second intake section (2212) is a reduced orifice with a gradually decreasing cross-sectional area, and the inclination angle is between 2° and 10°.

5. The fuel cell assembly according to claim 1, wherein, the first fixing structure (71) includes a plurality of first fixing tie rods (711), the second fixing structure (72) includes a plurality of second fixing tie rods (721), both ends of the plurality of first fixing tie rods (711) are connected to the first end plate structure (21) and the intermediate end plate structure (22) respectively through fasteners, and both ends of the plurality of second fixing tie rods (721) are connected to the second end plate structure (23) and the intermediate end plate structure (22) respectively through fasteners.

6. The fuel cell assembly according to claim 1, wherein, the electrical lead structure (80) includes a first current collector plate (81), a second current collector plate (82), a connecting copper bar (83), a third current collector plate (84), a fourth current collector plate (85), a first lead-out copper bar (86) and a second lead-out copper bar (87). The first current collector plate (81) is disposed between the intermediate end plate structure (22) and the first stack core structure (11), the second current collector plate (82) is disposed between the first stack core structure (11) and the first end plate structure (21), both ends of the connecting copper bar (83) are electrically connected to the first current collector plate (81) and the second current collector plate (82), the third current collector plate (84) is disposed between the second stack core structure (12) and the intermediate end plate structure (22), the first end of the first lead-out copper bar (86) is electrically connected to the first current collector plate (81), the fourth current collector plate (85) is disposed between the second stack core structure (12) and the second end plate structure (23), and the first end of the second lead-out copper bar (87) is electrically connected to the fourth current collector plate (85).

7. The fuel cell assembly according to claim 6, wherein, the fuel cell assembly further includes a first elastic member (91), a first insulating plate (92), a second elastic member (93) and a second insulating plate (94). The first insulating plate (92) is located between the second current collector plate (82) and the first end plate structure (21), the first elastic member (91) is located between the first insulating plate (92) and the first end plate structure (21), the first elastic member (91) is elastically abutted against the first insulating plate (92) and the first end plate structure (21), the second insulating plate (94) is located between the fourth current collector plate (85) and the second end plate structure (23), the second elastic member (93) is located between the second insulating plate (94) and the second end plate structure (23), and the second elastic member (93) is elastically abutted against the second insulating plate (94) and the second end plate structure (23).

8. The fuel cell assembly according to claim 1, wherein, the fuel cell assembly further includes a voltage sampling structure (95), and the voltage sampling structure (95) is connected to the bipolar plate of the core structure (10).

9. A pressing device for a fuel cell assembly, wherein, the fuel cell assembly pressing device is used to press the fuel cell assembly according to any one of claims 1 to 8, and the pressing device includes: a base structure (30), the base structure (30) includes a base (31), a support frame (32) and an upper platform (33), the bottom of the support frame (32) is connected to the base (31), and the upper platform (33) is located above the support frame (32); a lifting seat structure (40), the lifting seat structure (40) is arranged on the base (31); a flipping and clamping structure (50), the flipping and clamping structure (50) is arranged on the support frame (32); a pressing structure (60), the pressing structure (60) is installed on the upper platform (33); the clamping parts of the pressing structure (60), the lifting seat structure (40) and the flipping and clamping structure (50) are arranged corresponding to each other in the vertical direction.

10. The pressing device for a fuel cell assembly according to claim 9, wherein, the flipping and clamping structure (50) includes a driving part (51), a first clamping arm (52) and a second clamping arm (53), the support frame (32) includes a first support column and a second support column, the first clamping arm (52) is rotatably arranged on the first support column, the second clamping arm (53) is rotatably arranged on the second support column, the driving part (51) is fixed on the first support column, and the output end of the driving part (51) is connected to the first clamping arm (52).

11. The pressing device for a fuel cell assembly according to claim 10, wherein, the first clamping arm (52) includes a first spline (521), a bearing (522), a clamping seat (523), a telescopic rod (524) and a clamping part (525), the driving part (51) includes a servo motor and a second spline connected to the output shaft of the servo motor, the first spline (521) has a through hole, the inner wall of the first spline (521) is a spline structure, the inner wall of the first spline (521) is adapted to the outer wall of the second spline, the outer wall of the first spline (521) is matched with the inner ring of the bearing (522), the outer ring of the bearing (522) is fixed on the first support column, the clamping seat (523) is connected to the second spline, the telescopic rod (524) is fixed on the clamping seat (523), and the clamping part (525) is connected to the telescopic rod (524).

12. A pressing method for a fuel cell assembly, wherein, the pressing method uses the pressing device according to any one of claims 9 to 11, and the pressing method includes the following steps: Start the flipping and clamping structure (50) to clamp the intermediate end plate structure (22); Start the pressing structure (60) to press-fit the first core structure (11); After the pressing is completed, the pressing structure (60) returns to the initial position; Start the flipping and clamping structure (50) to flip 180 degrees; Start the pressing structure (60) to press-fit the second core structure (12); After the pressing is completed, the pressing structure (60) returns to the initial position; The flipping and clamping structure (50) returns to the initial position.

Images