A method and system for determining membrane electrode assembly force in a fuel cell stack

Abstract

The application provides a method and system for determining the membrane electrode assembly force in a fuel cell stack, comprising: in response to a first assembly force acting on a first stack, obtaining a relationship between different assembly forces and first pressure test data as a first relationship; and obtaining a relationship between different assembly forces and the online performance of the fuel cell stack as a second relationship; in response to a second assembly force acting on a second stack, obtaining a relationship between different assembly forces and second pressure test data as a third relationship; and obtaining a target assembly force value based on the first relationship, the second relationship and the third relationship. In this way, the multiple corresponding relationships between the assembly force and the performance of the stack are established by directly testing the pressure of the stack, the determination of the suitable assembly force is performed by comprehensively considering the pressure test and the performance, which is easy to implement, is not easily affected by temperature, and can obtain an accurate and suitable assembly force; meanwhile, the matching of the sealing material design can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fuel cells, and particularly relates to a method and system for determining the assembly force of a membrane electrode assembly in a fuel cell stack. BACKGROUND

[0002] The core components of a fuel cell include a proton exchange membrane electrode, which in turn includes a proton exchange membrane, a cathode and anode catalyst layer, and a cathode and anode gas diffusion layer. Among them, the gas diffusion layer (GDL) is the thickest component in the membrane electrode, and plays the roles of gas-liquid transmission, heat conduction, electricity conduction, and support. Under a small assembly force, the gas diffusion layer is less compressed, the electronic impedance is large, and the performance is low. With the increase of the assembly force, the electronic impedance decreases, and the mass transfer impedance gradually becomes prominent. The two are balanced in a certain assembly force range, and the high performance output can be maintained. With the continuous increase of the assembly force, the mass transfer impedance dominates and also affects the performance output of the battery. Therefore, only under a suitable stress state, the gas diffusion layer will have good gas-liquid transmission and heat conduction.

[0003] At present, in order to assemble the fuel cell properly and ensure the performance output of the battery, the output gas diffusion layer is roughly available assembly force and compression rate, and the research on the assembly force range suitable for the gas diffusion layer is mainly based on the force and displacement curve of the gas diffusion layer under offline flat plate compression, and the force and resistance curve. However, the high-power fuel cell stack has different temperature and humidity differences at the inlet and outlet, different electronic impedance and mass transfer impedance ratios, which will lead to inaccurate results of using the force and resistance curve to determine the available assembly force.

[0004] Therefore, for the fuel cell stack, how to obtain accurate and suitable assembly force is a technical problem that needs to be solved by those skilled in the art. SUMMARY

[0005] Therefore, the embodiments of the present application provide a method and device for determining the assembly force of a membrane electrode assembly in a fuel cell stack, aiming to obtain accurate and suitable assembly force of a fuel cell stack.

[0006] In a first aspect, the embodiments of the present application provide a method for determining the assembly force of a membrane electrode assembly in a fuel cell stack, comprising:

[0007] In response to the first assembly force acting on the first stack, the relationship between different assembly forces and first pressure test data is obtained as a first relationship, and the relationship between different assembly forces and the online performance of the fuel cell stack is obtained as a second relationship; the first stack is a stack of membrane electrode assemblies containing sealing materials, and the first pressure test data is the pressure data of the active reaction area of the membrane electrode assembly of the first stack;

[0008] In response to the second assembly force acting on the second stack, a relationship of different assembly forces and second pressure test data is obtained as a third relationship; the second stack is a stack of film electrodes assembled without sealing material, and the second pressure test data is pressure data of the active reaction region of the film electrode of the second stack;

[0009] Based on the first relationship, the second relationship and the third relationship, a target assembly force value is obtained, which is used to make the first pressure test data, the second pressure test data and the fuel cell stack online performance meet the first preset condition.

[0010] Optionally, the assembly force is applied by a pressing device, and the method further comprises:

[0011] In response to the second assembly force acting on the second stack, a pressing parameter corresponding to the different assembly forces is obtained, the pressing parameter being a displacement parameter when the pressing device applies different assembly forces;

[0012] An air pressure parameter and inherent parameters of the second stack are obtained, the air pressure parameter being a displacement parameter when the pressing device is air-pressured, and the inherent parameters of the second stack including structure and material parameters of the second stack;

[0013] The different assembly forces corresponding to the pressing parameters, the air pressure parameter and the inherent parameters of the second stack are used to calculate a compression rate corresponding to the different assembly forces, and a fourth relationship is obtained, the fourth relationship being a relationship of different assembly forces and compression rates;

[0014] Based on the first relationship, the second relationship, the third relationship and the fourth relationship, an optimal assembly force value is obtained, which is used to make the first pressure test data, the second pressure test data, the fuel cell stack online performance and the compression rate meet a second preset condition.

[0015] Optionally, the second pressure test data is obtained by a second pressure test device, the second pressure test device including pressure-sensitive paper, and the inherent parameters of the second stack including thickness of the film electrode of the second stack, thickness of the metal plate of the second stack, thickness of the pressure-sensitive paper and number of the film electrodes of the second stack;

[0016] The formula for calculating the compression rate includes:

[0017]

[0018] wherein, T0 is the air pressure parameter, T KN is the pressing parameter corresponding to the assembly force, t pre is the thickness of the pressure-sensitive paper, and N is the number of the film electrodes of the second stack, and t BPt is a thickness of a metal plate of the second stack M t is a thickness of a membrane electrode of the second stack.

[0019] Optionally, the fuel cell stack online performance includes normal temperature starting performance, polarization performance, low temperature high current density performance and / or low stoichiometric ratio performance, and the relationship between different assembly forces and the fuel cell stack online performance is obtained as the second relationship, including:

[0020] the relationship between different assembly forces and the normal temperature starting performance is obtained;

[0021] the relationship between different assembly forces and the polarization performance is obtained;

[0022] the relationship between different assembly forces and the low temperature high current density performance is obtained;

[0023] the relationship between different assembly forces and the low stoichiometric ratio performance is obtained.

[0024] In a second aspect, the embodiments of the present application provide a fuel cell stack membrane electrode assembly force determination system, comprising:

[0025] a first stack, a first pressing device, a first pressure testing device, an evaluation device, a second stack, a second pressing device, a second pressure testing device, and a controller;

[0026] The first stack and the second stack each include a current collector plate, an insulating plate, an end plate, a plurality of bipolar plates, and a plurality of membrane electrodes, and the membrane electrodes are located between the bipolar plates;

[0027] The first pressing device is configured to apply an assembly force acting on the first stack;

[0028] The first pressure testing device is located between the bipolar plates and the membrane electrodes of the first stack, and is configured to obtain first pressure testing data;

[0029] The evaluation device is configured to obtain a fuel cell stack online performance;

[0030] The second pressing device is configured to apply an assembly force acting on the second stack;

[0031] The second pressure testing device is located between the bipolar plates and the membrane electrodes of the second stack, and is configured to obtain second pressure testing data;

[0032] The controller is configured to execute the fuel cell stack membrane electrode assembly force determination method according to any one of the first aspect.

[0033] Optionally, the second pressure testing device includes pressure sensitive paper and a pressure sensitive paper scanner.

[0034] In a third aspect, the embodiments of the present application provide a device for determining the assembly force of a membrane electrode assembly in a fuel cell stack, comprising:

[0035] a sealing acquisition module configured to acquire a relationship between different assembly forces and first pressure test data as a first relationship in response to the first assembly force acting on a first stack, and acquire a relationship between different assembly forces and the online performance of the fuel cell stack as a second relationship; the first stack is a stack of membrane electrode assemblies containing sealing materials, and the first pressure test data is the pressure data of the active reaction region of the membrane electrode assembly in the first stack;

[0036] a non-sealing acquisition module configured to acquire a relationship between different assembly forces and second pressure test data as a third relationship in response to the second assembly force acting on a second stack; the second stack is a stack of membrane electrode assemblies not containing sealing materials, and the second pressure test data is the pressure data of the active reaction region of the membrane electrode assembly in the second stack;

[0037] a determination module configured to obtain a target assembly force value based on the first relationship, the second relationship and the third relationship, the target assembly force value being used to make the first pressure test data, the second pressure test data and the online performance of the fuel cell stack meet a first preset condition.

[0038] Optionally, the assembly force is applied by a pressing device, and the device further comprises:

[0039] a pressing parameter acquisition module configured to acquire the pressing parameters corresponding to different assembly forces in response to the second assembly force acting on the second stack, the pressing parameters being displacement parameters when the pressing device applies different assembly forces;

[0040] an inherent parameter acquisition module configured to acquire the air pressure parameter and the inherent parameters of the second stack, the air pressure parameter being a displacement parameter when the pressing device is air-pressing, and the inherent parameters of the second stack including the structure and material parameters of the second stack;

[0041] a calculation module configured to calculate the compression rates corresponding to different assembly forces by using the pressing parameters corresponding to different assembly forces, the air pressure parameter and the inherent parameters of the second stack, and obtain a fourth relationship, the fourth relationship being a relationship between different assembly forces and compression rates;

[0042] a preferred module configured to obtain a preferred assembly force value based on the first relationship, the second relationship, the third relationship and the fourth relationship, the preferred assembly force value being used to make the first pressure test data, the second pressure test data, the online performance of the fuel cell stack and the compression rates meet a second preset condition.

[0043] In a fourth aspect, an apparatus is provided, which includes a memory and a processor. The memory is configured to store instructions or code. The processor is configured to execute the instructions or code to cause the apparatus to perform the method for determining the membrane electrode assembly force in a fuel cell stack of any one of the preceding first aspect.

[0044] In a fifth aspect, a computer storage medium is provided, which stores code. When the code is executed, an apparatus executing the code performs the method for determining the membrane electrode assembly force in a fuel cell stack of any one of the preceding first aspect.

[0045] The embodiments of the present application provide a method and device for determining the membrane electrode assembly force in a fuel cell stack. When the method is executed, first, in response to a first assembly force acting on a first stack, a relationship between different assembly forces and first pressure test data is obtained as a first relationship. A relationship between different assembly forces and online performance of the fuel cell stack is obtained as a second relationship. The first stack is a stack in which a sealing material is used to assemble a membrane electrode. The first pressure test data is pressure data of an active reaction region of the membrane electrode of the first stack. Then, in response to a second assembly force acting on a second stack, a relationship between different assembly forces and second pressure test data is obtained as a third relationship. The second stack is a stack in which no sealing material is used to assemble a membrane electrode. The second pressure test data is pressure data of an active reaction region of the membrane electrode of the second stack. Finally, based on the first relationship, the second relationship and the third relationship, a target assembly force value is obtained. The target assembly force value is used to make the first pressure test data, the second pressure test data and the online performance of the fuel cell stack meet a first preset condition.

[0046] In this way, by directly testing the pressure of the stack, a plurality of corresponding relationships between the assembly force and the performance of the stack are established. The performance of the pressure test and the performance are comprehensively considered to determine the applicable assembly force. The determination is easy to implement and is not easily affected by temperature. An accurate and suitable assembly force can be obtained. Meanwhile, the matching of the sealing material design can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0047] To make the technical solutions in the embodiments or the prior art clearer, the accompanying drawings needed in the embodiments or the prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. Those skilled in the art can obtain other accompanying drawings according to the accompanying drawings without any creative effort.

[0048] Figure 1 A method flowchart of the method for determining the membrane electrode assembly force in a fuel cell stack provided by the embodiments of the present application is shown in FIG. 1.

[0049] Figure 2 A first relationship diagram of a method for determining a membrane electrode assembly force in a fuel cell stack is provided in an embodiment of the present application;

[0050] Figure 3 A second relationship diagram of a method for determining a membrane electrode assembly force in a fuel cell stack is provided in an embodiment of the present application;

[0051] Figure 4 A third relationship diagram of a method for determining a membrane electrode assembly force in a fuel cell stack is provided in an embodiment of the present application;

[0052] Figure 5 Another method flowchart of a method for determining a membrane electrode assembly force in a fuel cell stack is provided in an embodiment of the present application;

[0053] Figure 6 A fourth relationship diagram of a method for determining a membrane electrode assembly force in a fuel cell stack is provided in an embodiment of the present application;

[0054] Figure 7 A comparison diagram of thickness changes of a membrane electrode under pressure is provided in an embodiment of the present application;

[0055] Figure 8 A structure diagram of a device for determining a membrane electrode assembly force in a fuel cell stack is provided in an embodiment of the present application. DETAILED DESCRIPTION

[0056] The core components of a fuel cell include a proton exchange membrane electrode, and the proton exchange membrane electrode includes a proton exchange membrane, a cathode and anode catalyst layer, and a cathode and anode gas diffusion layer. Among them, the gas diffusion layer (GDL) as the largest component in the membrane electrode in thickness size, plays the role of gas-liquid transmission, heat conduction, electricity conduction, support, etc. Under a small assembly force, the gas diffusion layer is under small pressure, the electronic impedance is large, and the performance is low; with the increase of the assembly force, the electronic impedance decreases, and the mass transfer impedance gradually highlights, and the two are balanced in a certain assembly force range, which can maintain high performance output; with the continuous increase of the assembly force, the mass transfer impedance occupies the dominant position, which also affects the battery performance output. Therefore, only in the appropriate stress state, the gas diffusion layer will have good gas-liquid transmission and heat conduction.

[0057] At present, in order to assemble the fuel cell properly and ensure the battery performance output, the output gas diffusion layer is roughly available assembly force and compression rate, and the research on the assembly force range suitable for the gas diffusion layer is mainly based on the force and displacement curve of the gas diffusion layer under offline flat plate compression, and the force and resistance curve. However, the high-power fuel cell stack has different temperature and humidity differences at the inlet and outlet, different electronic impedance and mass transfer impedance ratios, which will lead to inaccurate results of using force and resistance curve to judge the available assembly force.

[0058] The method provided by the embodiments of the present application is executed by a controller, and is used to obtain accurate and appropriate assembly force of a fuel cell stack.

[0059] Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0060] Referring to Figure 1 , Figure 1 A method flow chart of the method for determining the assembly force of the membrane electrode assembly in the fuel cell stack provided by the embodiments of the present application comprises the following steps.

[0061] Step S101: In response to the first assembly force acting on the first stack, the relationship between the different assembly forces and the first pressure test data is obtained as a first relationship; and the relationship between the different assembly forces and the online performance of the fuel cell stack is obtained as a second relationship.

[0062] The fuel cell stack comprises current collectors on both sides of the stack, insulating plates, end plates, a plurality of bipolar plates and membrane electrodes between the bipolar plates. The first stack is a stack in which the membrane electrode is assembled with sealing material, and at this time, the membrane electrode is divided into an active reaction area and a sealing area. The active reaction area comprises a proton membrane, a catalytic layer and a gas diffusion layer; and the sealing material is located between the bipolar plate and the periphery of the membrane electrode, forming the sealing area. The bipolar plate is provided with the sealing material.

[0063] The first assembly force can be applied to the first stack by a first pressure applying device. As a possible implementation, the first pressure applying device can be any one of a torque wrench or an electronic pressing device (pneumatic, hydraulic, etc.).

[0064] The first pressure test data is the pressure data of the active reaction area of the membrane electrode of the first stack obtained by a pressure test device. The pressure test device covers the active reaction area and the sealing area, and can be placed between the bipolar plate and the membrane electrode in the selected area of the cell, preferably in the middle or upper and lower parts of the cell.

[0065] As a possible implementation, the first pressure test device can be any one of a pressure test device and a data acquisition device, pressure-sensitive paper and a pressure-sensitive paper scanner, a pressure blanket and a data acquisition device, or a pressure film sensing sheet and a data acquisition device.

[0066] The fuel cell stack on-line performance includes one or more of the following performances: normal temperature starting performance, polarization performance, low temperature high current density performance, and / or low stoichiometric ratio performance. The performances are specifically manifested as changes in output voltage, impedance, flow resistance, consistency, etc. The above performances can be obtained by using common fuel cell development test equipment such as a stack performance test bench, a full-frequency impedance tester, a constant potential instrument (using current step method to measure impedance), etc.

[0067] Thus, the relationship between different assembly forces and the fuel cell stack on-line performance is obtained as the second relationship, which can include: obtaining the relationship between different assembly forces and the normal temperature starting performance; obtaining the relationship between different assembly forces and the polarization performance; obtaining the relationship between different assembly forces and the low temperature high current density performance; and obtaining the relationship between different assembly forces and the low stoichiometric ratio performance.

[0068] Specifically, in the implementation process, the initial value of the first assembly force can be set, and then the size of the first assembly force is gradually increased, and the pressure test data and the performance of the fuel cell stack on-line performance are recorded constantly to obtain the first relationship and the second relationship. See Figure 2 、 Figure 3 , Figure 2 The first relationship diagram of the fuel cell stack membrane electrode assembly force determination method provided by the embodiment of the application. Figure 3 The second relationship diagram of the fuel cell stack membrane electrode assembly force determination method provided by the embodiment of the application.

[0069] As a preferred embodiment, two identical first stacks can be stacked to obtain the first relationship and the second relationship, respectively, to improve the efficiency and accuracy of the assembly force determination.

[0070] Step S102: obtaining the relationship between different assembly forces and the second pressure test data as a third relationship in response to the second assembly force acting on the second stack.

[0071] The fuel cell stack includes current collecting plates, insulating plates, end plates, a plurality of bipolar plates, and membrane electrodes between the bipolar plates. The second stack is a stack of membrane electrodes assembled without sealing materials. The second pressure test data is the pressure data of the active reaction area of the membrane electrode of the second stack obtained by the pressure test device. The pressure test device can be any one of the following devices: a pressure test device and data acquisition equipment, pressure sensitive paper and a pressure sensitive paper scanner, a pressure blanket and data acquisition equipment, or a pressure film sensing sheet and data acquisition equipment.

[0072] The second assembly force can be applied to the second stack by the second pressing device. As a possible implementation, considering the uniform stress problem, the second pressing device can be any one of the electronic pressing equipment (pneumatic, hydraulic, etc.).

[0073] Specifically, in the implementation process, an initial value of the second assembly force can be set, and then the size of the second assembly force is gradually increased, and the performance of the pressure test data is recorded continuously to obtain the third relationship. Referring to Figure 4 , Figure 4 The third relationship diagram of the fuel cell stack membrane electrode assembly force determination method provided by the embodiment of the application.

[0074] Step S103: obtaining a target assembly force value based on the first relationship, the second relationship and the third relationship.

[0075] The first relationship, the second relationship and the third relationship respectively reflect the influence and effect of the assembly force on the fuel cell under different conditions. In order to maintain the performance of the battery in a good state, the above performance is required to achieve the best assembly force value as the target assembly force value. Therefore, a first preset condition can be set in advance to set the applicable range of the relationship between the first pressure test data, the fuel cell stack online performance and the second pressure test data. It should be noted that the first preset condition can be set according to actual needs, which is not limited here.

[0076] In summary, the embodiment directly tests the pressure of the stack, establishes multiple corresponding relationships between the assembly force and the performance of the stack, determines the applicable assembly force by comprehensively considering the performance of the pressure test and the performance, is easy to implement, is not easily affected by temperature, and can obtain accurate and appropriate assembly force; at the same time, the matching of the sealing material design can be improved. Combined with the pressure assembly device and the stack performance test bench and other common fuel cell development test equipment, the corresponding relationship between the stack pressure assembly force, the compression rate and the performance parameters is established, which is easy to implement, simple to operate, outputs the applicable assembly force and compression rate of the membrane electrode in the fuel cell stack, and improves the matching and accuracy of the sealing material design.

[0077] In the embodiment of the application, the above Figure 1 The steps described above have various possible implementation manners, which will be introduced below. It should be noted that the implementation manners given in the following introduction are only exemplary and do not represent all implementation manners of the embodiment of the application.

[0078] Referring to Figure 5 , the figure is another method flowchart of the fuel cell stack membrane electrode assembly force determination method provided by the embodiment of the application, which includes:

[0079] Step S501: in response to the first assembly force acting on the first stack, obtaining the relationship between different assembly forces and the first pressure test data as the first relationship; and obtaining the relationship between different assembly forces and the online performance of the fuel cell stack as the second relationship.

[0080] As one possible implementation, 15 short stacks can be piled up (including 15 brand-new membrane electrodes, 1 cathode monopole, 1 anode monopole, 14 bipolar plates, and metal plates with sealing material). Pressure-sensitive paper is placed between the intermediate bipolar plate and the membrane electrode, and the pressure readings of the pressure-sensitive paper in the active area of ​​the membrane electrode are measured when assembled with torques ranging from 8-22 Nm from small to large. The first relationship is obtained based on this reading.

[0081] A new stack of 15 short stacks (including 15 brand-new membrane electrodes, 1 cathode monopole plate, 1 anode monopole plate, 14 bipolar plates, and metal plates with sealing material) was assembled using 8 Nm of torque, and performance testing and evaluation were completed. The torque was then increased sequentially by 2-4 Nm, and performance testing and evaluation were completed. Based on this, the second relationship was obtained.

[0082] As one possible implementation, to save costs, 15 short stacks can be shared in the same stack.

[0083] Step S502: In response to the second assembly force acting on the second fuel cell, obtain the relationship between different assembly forces and the second pressure test data as a third relationship.

[0084] As one possible implementation, a new stack of 15 short sections is used (15 brand-new membrane electrodes, 1 cathode monopole, 1 anode monopole, and 14 bipolar plates; the metal plates contain no sealing material to ensure that only the membrane electrodes are subjected to force). Pressure-sensitive paper is placed between the middle bipolar plate and the membrane electrode, and the pressure readings of the pressure-sensitive paper in the active area of ​​the membrane electrode are measured under pressures of 12kN-36kN. The third relationship is obtained based on this reading.

[0085] Step S503: Based on the first relationship, the second relationship and the third relationship, obtain the target assembly force value.

[0086] Step S504: In response to the second assembly force acting on the second fuel cell stack, obtain the pressure parameters corresponding to different assembly forces.

[0087] The pressure parameter refers to the displacement parameter when the pressure-applying device applies different assembly forces. As one possible implementation, the electronic pressing equipment has a built-in displacement data recorder or an external displacement sensor. In response to the second assembly force acting on the second fuel cell stack, the displacement reading of the pressure-applying device under pressures of 12kN-36kN is measured and used as the pressure parameter.

[0088] Step S505: Obtain the air pressure parameters and the inherent parameters of the second fuel cell stack.

[0089] The air pressure parameter refers to the displacement parameter when the pressurizing device is pressurized with air. The inherent parameters of the second fuel cell stack include the structural and material parameters of the second fuel cell stack. As one possible implementation, the displacement reading T0 can be obtained as the air pressure parameter when the compressor air pressure is 12kN-36kN.

[0090] Step S506: calculating the compression rate corresponding to different assembly forces by using the pressure parameters corresponding to the different assembly forces, the air pressure parameters and the inherent parameters of the second stack, and obtaining a fourth relationship.

[0091] The fourth relationship is the relationship between different assembly forces and compression rates. Since the compression rate can be used repeatedly in subsequent links, the compression rate can also be used as one of the standards for selecting the assembly force.

[0092] As a possible implementation, the second pressure test data is obtained by pressure-sensitive paper. At this time, the inherent parameters of the second stack include the thickness of the membrane electrode of the second stack, the thickness of the metal plate of the second stack, the thickness of the pressure-sensitive paper, and the number of membrane electrodes of the second stack; and the calculation formula of the compression rate is:

[0093]

[0094] wherein T0 is the air pressure parameter, T KN is the pressure parameter corresponding to the assembly force, t pre is the thickness of the pressure-sensitive paper, N is the number of membrane electrodes of the second stack, t BP is the thickness of the metal plate of the second stack, and t M is the thickness of the membrane electrode of the second stack.

[0095] Step S507: obtaining the preferred assembly force value based on the first relationship, the second relationship, the third relationship and the fourth relationship.

[0096] The preferred assembly force value is used to make the first pressure test data, the second pressure test data, the online performance of the fuel cell stack and the compression rate meet the second preset condition. The second preset condition can be set in advance to set the applicable range of the first pressure test data, the online performance of the fuel cell stack, the second pressure test data relationship and the compression rate. It should be noted that the second preset condition can be set according to actual needs, which is not limited herein.

[0097] As a possible implementation, the method further comprises: assembling the membrane electrode in the fuel cell stack by using the assembly force corresponding to the target assembly force value or the preferred assembly force value. Preferably, since the gas diffusion layer is a porous material, the thickness of the membrane electrode changes after being pressed, and the curves of the first round and the subsequent rounds are different (see Figure 7 , Figure 7 the comparative diagram of the thickness change of the membrane electrode under pressure provided by the embodiments of the present application), and the assembly process is recommended to be repeated 3-5 times to ensure that the force and displacement curves are stable.

[0098] To sum up, the embodiment calculates the compression rate to obtain more accurate assembly force, and the implementation manner of the embodiment is specifically pointed out, which is easy to implement, simple to operate, and more applicable.

[0099] The above are some specific implementation manners of the method for determining the assembly force of the membrane electrode assembly in the fuel cell stack provided by the embodiment of the application. Based on this, the application also provides a corresponding system. The system provided by the embodiment of the application is introduced below.

[0100] The first electric stack, the first pressure applying device, the first pressure testing device, the evaluation device, the second electric stack, the second pressure applying device, the second pressure testing device, and the controller are provided.

[0101] The first electric stack and the second electric stack each include a current collector plate, an insulating plate, an end plate, a plurality of bipolar plates, and a plurality of membrane electrodes, and the membrane electrodes are located between the bipolar plates.

[0102] The first pressure applying device is configured to apply the assembly force acting on the first electric stack.

[0103] The first pressure testing device is located between the bipolar plate and the membrane electrode of the first electric stack and is configured to obtain first pressure testing data.

[0104] The evaluation device is configured to obtain the online performance of the fuel cell stack.

[0105] The second pressure applying device is configured to apply the assembly force acting on the second electric stack.

[0106] The second pressure testing device is located between the bipolar plate and the membrane electrode of the second electric stack and is configured to obtain second pressure testing data.

[0107] The controller is configured to execute the method for determining the assembly force of the membrane electrode assembly in the fuel cell stack described in the above embodiment.

[0108] As a possible implementation manner, the first pressure applying device includes a torque wrench and / or an electronic pressing device (pneumatic or hydraulic).

[0109] As a possible implementation manner, the first pressure testing device includes a pressure testing device and a data acquisition device, pressure-sensitive paper and a pressure-sensitive paper scanner, a pressure blanket and a data acquisition device, and / or a pressure film sensing sheet and a data acquisition device.

[0110] As a possible implementation manner, the evaluation device includes an electric stack performance test bench, a full-frequency impedance tester, and / or a constant potential instrument.

[0111] As a possible implementation manner, the second pressure applying device includes a torque wrench and / or an electronic pressing device (pneumatic or hydraulic).

[0112] As a possible implementation, the second pressure testing device comprises a pressure testing device and a data acquisition device, pressure sensitive paper and a pressure sensitive paper scanner, a pressure blanket and a data acquisition device, and / or a pressure film sensing sheet and a data acquisition device.

[0113] The application also provides a corresponding device, which will be introduced from the perspective of functional modularization.

[0114] Referring to Figure 8 The structure diagram of the membrane electrode assembly force determination device in the fuel cell stack is shown in the figure, and the device comprises a sealing acquisition module 801, a non-sealing acquisition module 802 and a determination module 803.

[0115] The sealing acquisition module 801 is configured to, in response to the first assembly force acting on the first stack, acquire a relationship between different assembly forces and first pressure testing data as a first relationship, and acquire a relationship between different assembly forces and online performance of the fuel cell stack as a second relationship; the first stack is a stack of membrane electrodes assembled with sealing materials, and the first pressure testing data is pressure data of the active reaction region of the membrane electrode of the first stack;

[0116] The non-sealing acquisition module 802 is configured to, in response to the second assembly force acting on the second stack, acquire a relationship between different assembly forces and second pressure testing data as a third relationship; the second stack is a stack of membrane electrodes assembled without sealing materials, and the second pressure testing data is pressure data of the active reaction region of the membrane electrode of the second stack;

[0117] The determination module 803 is configured to obtain a target assembly force value based on the first relationship, the second relationship and the third relationship, and the target assembly force value is used to make the first pressure testing data, the second pressure testing data and the online performance of the fuel cell stack meet a first preset condition.

[0118] As a possible implementation, the device further comprises:

[0119] The pressure applying parameter acquisition module is configured to, in response to the second assembly force acting on the second stack, acquire a pressure applying parameter corresponding to different assembly forces, the pressure applying parameter being a displacement parameter when the pressure applying device applies different assembly forces;

[0120] The inherent parameter acquisition module is configured to acquire an air pressure parameter and an inherent parameter of the second stack, the air pressure parameter being a displacement parameter when the pressure applying device is air pressure, and the inherent parameter of the second stack including a structure and material parameter of the second stack;

[0121] The computing module is configured to calculate a compression rate corresponding to different assembly forces by using the pressure applying parameter corresponding to the different assembly forces, the air pressure parameter, and an inherent parameter of the second stack, and obtain a fourth relationship between different assembly forces and the compression rate.

[0122] The preferred module is configured to obtain a preferred assembly force value based on the first relationship, the second relationship, the third relationship, and the fourth relationship, so that the first pressure test data, the second pressure test data, the fuel cell stack online performance, and the compression rate meet a second preset condition.

[0123] As a possible implementation, the second pressure test data is obtained by a second pressure test device, and the second pressure test device includes pressure sensitive paper. The inherent parameters of the second stack include a thickness of a membrane electrode of the second stack, a thickness of a metal plate of the second stack, a thickness of the pressure sensitive paper, and a number of membrane electrodes of the second stack.

[0124] The formula for calculating the compression rate includes:

[0125]

[0126] wherein, T0 is the air pressure parameter, T KN is the pressure applying parameter corresponding to the assembly force, t pre is the thickness of the pressure sensitive paper, N is the number of membrane electrodes of the second stack, t BP is the thickness of the metal plate of the second stack, t M is the thickness of the membrane electrode of the second stack.

[0127] As a possible implementation, the fuel cell stack online performance includes a normal temperature startup performance, a polarization performance, a low temperature high current density performance, and / or a low stoichiometric ratio performance. The sealing obtaining module 801 includes:

[0128] A first obtaining unit is configured to obtain a relationship between different assembly forces and the normal temperature startup performance.

[0129] A second obtaining unit is configured to obtain a relationship between different assembly forces and the polarization performance.

[0130] A third obtaining unit is configured to obtain a relationship between different assembly forces and the low temperature high current density performance.

[0131] A fourth obtaining unit is configured to obtain a relationship between different assembly forces and the low stoichiometric ratio performance.

[0132] Embodiments of the present application also provide a corresponding device and a computer storage medium for implementing the scheme provided by the embodiments of the present application.

[0133] The device includes a memory and a processor, the memory is used to store instructions or codes, and the processor is used to execute the instructions or codes to make the device execute the fuel cell stack membrane electrode assembly force determination method described in any embodiment of the application.

[0134] The computer storage medium stores codes, when the codes are executed, the device executing the codes implements the fuel cell stack membrane electrode assembly force determination method described in any embodiment of the application.

[0135] The "first", "second" in the names mentioned in the embodiments of the present application are only used for name identification, and do not represent the first and second in order.

[0136] From the description of the above embodiments, those skilled in the art can clearly understand that all or part of the steps in the above embodiment methods can be implemented by means of software plus a general hardware platform. Based on such understanding, the technical solutions of the present application can be embodied in the form of a software product. The computer software product can be stored in a storage medium, such as a read-only memory (English: read-only memory, ROM) / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions to make a computer device (which can be a personal computer, a server, or a network communication device such as a router) execute the methods described in various embodiments or some parts of the embodiments of the present application.

[0137] Each embodiment in the specification is described in a progressive manner, and the same and similar parts between each embodiment can be referred to each other. Each embodiment focuses on the difference from other embodiments. Especially, since the device embodiment is basically similar to the method embodiment, it is described more simply, and the relevant parts can be referred to the part of the method embodiment. According to the actual needs, some or all of the modules can be selected to achieve the purpose of the embodiment. Those skilled in the art can understand and implement without creative labor.

[0138] The above is only an exemplary embodiment of the present application, and is not used to limit the protection scope of the present application.

Claims

1. A method of determining a membrane electrode assembly force in a fuel cell stack, characterized by, The method comprises: obtaining a relationship between different assembly forces and first pressure test data as a first relationship in response to the first assembly force acting on the first stack, and obtaining a relationship between different assembly forces and fuel cell stack online performance as a second relationship; the first stack is a stack of membrane electrodes assembled with sealing materials, and the first pressure test data is the pressure data of the active reaction region of the membrane electrode of the first stack; obtaining a relationship between different assembly forces and second pressure test data as a third relationship in response to the second assembly force acting on the second stack; the second stack is a stack of membrane electrodes assembled without sealing materials, and the second pressure test data is the pressure data of the active reaction region of the membrane electrode of the second stack; obtaining a target assembly force value based on the first relationship, the second relationship and the third relationship, the target assembly force value being used to make the first pressure test data, the second pressure test data and the fuel cell stack online performance meet a first preset condition; the assembly force is applied by a pressure applying device; obtaining a pressure applying parameter corresponding to the different assembly forces in response to the second assembly force acting on the second stack, the pressure applying parameter being a displacement parameter when the pressure applying device applies different assembly forces; obtaining an air pressure parameter and inherent parameters of the second stack, the air pressure parameter being a displacement parameter when the pressure applying device is air-pressured, and the inherent parameters of the second stack including structure and material parameters of the second stack; calculating a compression rate corresponding to different assembly forces by using the pressure applying parameter corresponding to the different assembly forces, the air pressure parameter and the inherent parameters of the second stack, and obtaining a fourth relationship, the fourth relationship being a relationship between different assembly forces and compression rates; obtaining an optimal assembly force value based on the first relationship, the second relationship, the third relationship and the fourth relationship, the optimal assembly force value being used to make the first pressure test data, the second pressure test data, the fuel cell stack online performance and the compression rate meet a second preset condition.

2. The method of claim 1, wherein, The second pressure test data is obtained by a second pressure test device, the second pressure test device comprising pressure-sensitive paper, and the inherent parameters of the second stack including thickness of the membrane electrode of the second stack, thickness of the metal plate of the second stack, thickness of the pressure-sensitive paper and number of the membrane electrode of the second stack; The formula for calculating the compression rate comprises: ； Wherein, T0 is the air pressure parameter, T KN is the assembly force corresponding to the pressure parameter, t pre is the thickness of the pressure-sensitive paper, N is the number of membrane electrodes of the second electric pile, t BP is the thickness of the metal plate of the second electric pile, t M is the thickness of the membrane electrode of the second electric pile.

3. The method of claim 1, wherein, The fuel cell stack online performance includes normal temperature starting performance, polarization performance, low temperature high current density performance and low stoichiometric ratio performance, and the obtaining of the relationship between different assembly forces and fuel cell stack online performance as a second relationship comprises: obtaining a relationship between different assembly forces and the normal temperature starting performance; obtaining a relationship between different assembly forces and the polarization performance; obtaining a relationship between different assembly forces and the low temperature high current density performance; obtaining a relationship between different assembly forces and the low stoichiometric ratio performance.

4. A fuel cell stack intra-membrane electrode assembly force determination system characterized by comprising: The system comprises: a first stack, a first pressure applying device, a first pressure test device, an evaluation device, a second stack, a second pressure applying device, a second pressure test device and a controller. The first and second stacks each comprise a current collector plate, an insulating plate, an end plate, a plurality of bipolar plates and a plurality of membrane electrodes, the membrane electrodes being located between the bipolar plates; The first pressure applying device is configured to apply an assembly force acting on the first stack; The first pressure testing device is located between the bipolar plates and the membrane electrodes of the first stack and is configured to obtain first pressure testing data; The evaluation device is configured to obtain the on-line performance of the fuel cell stack; The second pressure applying device is configured to apply an assembly force acting on the second stack; The second pressure testing device is located between the bipolar plates and the membrane electrodes of the second stack and is configured to obtain second pressure testing data; The controller is configured to perform the method for determining the assembly force of the membrane electrode in the fuel cell stack according to any one of claims 1 to 3.

5. The system of claim 4, wherein, The second pressure testing device comprises pressure-sensitive paper and a pressure-sensitive paper scanner.

6. A device for determining the assembly force of an inner membrane electrode in a fuel cell stack, characterized in that, The device comprises: A sealing obtaining module configured to, in response to the first assembly force acting on the first stack, obtain a relationship between different assembly forces and the first pressure testing data as a first relationship, and obtain a relationship between different assembly forces and the on-line performance of the fuel cell stack as a second relationship; the first stack is a stack in which the membrane electrode is assembled with sealing material, and the first pressure testing data is pressure data of the active reaction region of the membrane electrode of the first stack; A non-sealing obtaining module configured to, in response to the second assembly force acting on the second stack, obtain a relationship between different assembly forces and the second pressure testing data as a third relationship; the second stack is a stack in which the membrane electrode is assembled without sealing material, and the second pressure testing data is pressure data of the active reaction region of the membrane electrode of the second stack; A determining module configured to, based on the first relationship, the second relationship and the third relationship, obtain a target assembly force value, the target assembly force value being used to make the first pressure testing data, the second pressure testing data and the on-line performance of the fuel cell stack meet a first preset condition; the assembly force is applied by a pressure applying device; A pressure applying parameter obtaining module configured to, in response to the second assembly force acting on the second stack, obtain pressure applying parameters corresponding to different assembly forces, the pressure applying parameters being displacement parameters when the pressure applying device applies different assembly forces; An inherent parameter obtaining module configured to obtain an air pressure parameter and inherent parameters of the second stack, the air pressure parameter being a displacement parameter when the pressure applying device is in air pressure, and the inherent parameters of the second stack including structural and material parameters of the second stack; A calculating module configured to, using the pressure applying parameters corresponding to different assembly forces, the air pressure parameter and the inherent parameters of the second stack, calculate compression rates corresponding to different assembly forces, and obtain a fourth relationship, the fourth relationship being a relationship between different assembly forces and compression rates; A preferred module configured to, based on the first relationship, the second relationship, the third relationship and the fourth relationship, obtain a preferred assembly force value, the preferred assembly force value being used to make the first pressure testing data, the second pressure testing data, the on-line performance of the fuel cell stack and the compression rates meet a second preset condition.

7. An apparatus, comprising: The device comprises a memory for storing instructions or codes and a processor for executing the instructions or codes to make the device execute the method for determining the membrane-electrode assembly force in a fuel cell stack according to any one of claims 1 to 3.

8. A computer storage medium, characterized in that The computer storage medium stores codes, and when the codes are run, the computer storage device running the codes implements the method for determining the membrane-electrode assembly force in a fuel cell stack according to any one of claims 1 to 3.

Images