Single cell testing method, battery stack preparation method, and fuel cell

Abstract

The present application provides a single cell testing method, a method for preparing a fuel cell stack, and a fuel cell. The single cell testing method includes: providing a single cell; applying multiple preset test pressures to the single cell respectively, and obtaining multiple test compressions corresponding to the multiple preset test pressures; and judging whether the single cell is qualified based on the multiple preset test pressures and the multiple test compressions. The present application judges whether the single cell is qualified based on the preset test pressures and the test compressions, thereby screening out single cells whose compressions meet the requirements under the preset test pressures. When making a fuel cell stack, the single cells that meet the requirements can be stacked, and then after applying the stacking pressure to the multiple single cells, the overall size of the fuel cell stack can be controlled, which can avoid the phenomenon that the fuel cell size does not match the design value after the stack is compressed, thereby affecting subsequent assembly.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a single cell testing method, a battery stack preparation method, and a fuel cell. Background Art

[0002] Currently, the membrane electrode in a fuel cell stack consists of a cathode plate and an anode plate on either side. A hydrogen flow field is formed between the anode plate and the membrane electrode, while an oxygen flow field is formed between the cathode plate and the membrane electrode. During the reaction, the hydrogen on the membrane electrode side of the anode plate reacts to produce protons. The protons pass through the membrane electrode and the oxygen on the cathode plate side to produce water. Because this reaction generates a large amount of heat, a sealed cooling water flow field is required between the adjacent cathode and anode plates through seals to absorb the heat generated during the reaction.

[0003] In the prior art, the cathode plate, membrane electrode and anode plate can be pre-bonded in sequence to form a single cell, and then multiple single cells can be stacked to form a fuel cell stack. After the fuel cell stack is formed, it is usually necessary to apply a certain pressure to the cell stack to ensure the sealing performance of the plate and the sealing ring and the conductivity between adjacent plates. However, applying pressure to the cell stack will cause the single cells in the stack to be compressed (for example, the sealing ring between the plates, the gas diffusion layer of the membrane electrode, etc. are compressed), which makes the individual size of the single cell after the stacking and the overall size of the stack uncontrollable, and the stack size may not match the design value under the design pressure and affect the subsequent assembly process. Summary of the Invention

[0004] The present application provides a single cell testing method, a method for preparing a battery stack, and a fuel cell, aiming to solve the current technical problem that the battery stack size does not conform to the design value after compression.

[0005] In a first aspect, the present application provides a single-cell battery testing method, comprising:

[0006] A single cell is provided, wherein the single cell comprises an anode plate, a membrane electrode, and a cathode plate which are stacked and fixed in sequence;

[0007] Applying a plurality of preset test pressures to the single cells respectively, and obtaining a plurality of test compressions corresponding to the plurality of preset test pressures, wherein the preset test pressures correspond to the test compressions in a one-to-one manner;

[0008] The qualification of a single battery cell is determined based on multiple preset test pressures and multiple test compression amounts.

[0009] In some embodiments, the step of determining whether a single battery is qualified based on a preset test pressure and a test compression amount includes:

[0010] Determining a compression change curve of a single battery according to a plurality of preset test pressures and a plurality of test compression amounts;

[0011] Whether the single cell is qualified is determined based on the compression change curve and the preset change curve. The preset change curve is the optimal compression change curve that indicates the single cell is qualified under multiple preset test pressures.

[0012] In some embodiments, the step of determining whether a single battery is qualified based on the compression change curve and the preset change curve includes:

[0013] Determine the maximum compression difference according to the compression change curve and the preset change curve;

[0014] Integrating the compression change curve and the preset change curve to determine an integral difference between the compression change curve and the preset change curve;

[0015] Whether the single battery is qualified is determined based on the maximum compression difference and the integral difference.

[0016] In some embodiments, the step of determining whether a single battery is qualified based on a plurality of preset test pressures and a plurality of test compression amounts includes:

[0017] Determine the preset compression amount and test compression amount corresponding to the stack pressure, the preset compression amount is the optimal compression amount that indicates that the single battery is qualified under the stack pressure, and the stack pressure is equal to a preset test pressure;

[0018] Determine whether the single battery is qualified based on the preset compression amount and the test compression amount.

[0019] In a second aspect, the present application provides a method for preparing a fuel cell stack, comprising:

[0020] Providing a preset number of single cells that have passed the test method described in the first aspect;

[0021] A preset number of single cells are stacked in sequence, and a stacking pressure is applied to the stacked single cells to form a battery stack with a preset size.

[0022] In some embodiments, the step of providing a preset number of single cells that have passed the test method described in the first aspect includes:

[0023] Providing a plurality of single cells that have passed the test according to the test method of the first aspect;

[0024] A preset number of single cells are selected from a plurality of single cells, wherein different single cells have different compression amounts under a stacking pressure, and the sum of the compression amounts of the single cells, the original size of the single cells, and the preset size satisfy the following relationship:

[0025] H=n*h-h0

[0026] Wherein, H is the preset size of the battery stack after compression, n is the preset number, h is the original size of the single cell, and h0 is the sum of the compression amounts of the single cells.

[0027] In some embodiments, the steps of stacking a preset number of single cells in sequence and applying a stacking pressure to the stacked single cells to form a battery stack having a preset size include:

[0028] Stacking a preset number of single batteries in sequence along a preset direction according to the compression amount, wherein the compression amount of the stacked single batteries increases in sequence along the preset direction;

[0029] A stacking pressure is applied to the stacked single cells for stacking, and the direction of the stacking pressure is opposite to the preset direction.

[0030] In some embodiments, the predetermined direction is parallel to the horizontal plane; or

[0031] The preset direction is perpendicular to the horizontal plane.

[0032] In some embodiments, during the process of applying a stacking pressure to the stacked single cells, the stacking pressure gradually increases.

[0033] In a third aspect, the present application provides a fuel cell comprising a fuel cell stack prepared by the method described in the second aspect.

[0034] This application applies a preset test pressure to a single cell and measures the test compression of the single cell, ultimately judging whether the single cell is qualified based on the preset test pressure and the test compression, thereby screening out single cells whose compression meets the requirements under the preset test pressure. When constructing a fuel cell stack, the single cells that meet the requirements can be stacked, and then after applying a stacking pressure to multiple single cells, the overall size of the fuel cell stack can be controlled, ensuring that the size of the stack after compression under the preset stacking force still meets the design value. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0036] Figure 1 This is a schematic diagram of a scenario of a single cell battery testing system provided in an embodiment of the present application;

[0037] Figure 2This is a flow chart of a single cell battery testing method provided in an embodiment of the present application;

[0038] Figure 3 This is a flow chart of determining whether a single cell current is qualified, provided in an embodiment of the present application;

[0039] Figure 4 This is a flow chart of determining whether a single cell current is qualified, provided in an embodiment of the present application;

[0040] Figure 5 This is a flow chart of a method for preparing a fuel cell stack provided in an embodiment of the present application;

[0041] Figure 6 This is another flow chart of the method for preparing a fuel cell stack provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0043] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0044] In this application, the word "exemplary" is used to mean "serving as an example, illustration, or illustration." Any embodiment described in this application as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. The following description is given to enable any person skilled in the art to make and use the invention. In the following description, details are listed for the purpose of explanation. It should be understood that one of ordinary skill in the art will recognize that the invention can be practiced without these specific details. In other instances, well-known structures and processes are not described in detail to avoid obscuring the description of the invention with unnecessary detail. Therefore, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

[0045] The embodiments of the present application provide a single cell testing method, a method for preparing a battery stack, and a fuel cell, which are described in detail below.

[0046] First, see Figure 1 , Figure 1 A schematic diagram of a single cell battery test system in an embodiment of the present application is shown. In the single cell battery test scenario, the compression amount of the single cell battery under a certain pressure can be detected to determine whether the single cell battery is qualified. Figure 1 As shown, the single cell battery testing system includes a server 101 , a thickness detection sensor 102 , a network 103 and a storage device 104 .

[0047] The server 101 can receive and / or process data and / or information from at least one component in the single cell battery testing system or an external data source (e.g., the storage device 104 or the thickness detection sensor 102). For example, the server 101 can receive data related to the compression amount of the single cell battery sent by the thickness detection sensor 102; for another example, the server 101 can receive data related to the compression amount of the single cell battery sent by the storage device 104. In some embodiments of the present application, the server 101 can be a single server or a server group. In some embodiments of the present application, the server can be a host computer directly connected to the circuit breaker system, or a master station or remote server on a communication bus.

[0048] The thickness detection sensor 102 can detect the compression of a single cell to determine whether the cell is qualified. In some embodiments of the present application, the thickness detection sensor 102 can detect the thickness of the cell after compression, and then calculate the compression of the cell by comparing the compressed thickness with the initial thickness. In some embodiments of the present application, the thickness detection sensor 102 can also detect the initial thickness of the cell to avoid the phenomenon where the initial thickness of different cells is inconsistent, resulting in a certain error in the compression of the cell. For example, the thickness detection sensor 102 can be a laser sensor or an ultrasonic sensor.

[0049] The network 103 connects the various components in the single-cell battery test system so that the components can communicate with each other to facilitate the exchange of information and / or data. In some embodiments, at least one component in the single-cell battery test system (e.g., server 101, storage device 104, thickness detection sensor 102) can send information and / or data (e.g., the compression amount of the single cell, the thickness after compression, etc.) to other components via the network 103. In some embodiments, the network between the various components in the circuit breaker anomaly detection scenario can be any one or more of a wired network or a wireless network. For example, the network 103 can include a cable network, a wired network, a fiber optic network, a telecommunications network, an internal network, the Internet, a local area network, an internal bus within a device, a line within a device, a cable connection, etc., or any combination thereof.

[0050] The storage device 104 can store data and / or instructions. In some embodiments, the storage device 104 can store the compression data of the single cell obtained from the thickness detection sensor 102. For another example, the storage device 104 can store logs related to the single cell testing system. In some embodiments, the storage device 104 can store data and / or instructions that can be executed by the server 101. In some embodiments, the storage device 104 may include a large-capacity memory, a removable memory, a volatile read-write memory, a read-only memory (ROM), etc. or any combination thereof. Exemplarily, the large-capacity memory may include a magnetic disk, an optical disk, a solid-state disk, etc. In some embodiments, the storage device 104 can be implemented on a cloud platform.

[0051] It should be noted that the above description of the anomaly detection application scenario is for illustrative purposes only and does not limit the scope of application of this application. Those skilled in the art will be able to make various modifications and changes to the anomaly detection application scenario under the guidance of this application. For example, a reminder device may be provided to alert relevant personnel when a single battery is detected to be unqualified.

[0052] See Figure 2 , Figure 2A schematic flow chart of a single cell battery testing method in an embodiment of the present application is shown, wherein the single cell battery testing method includes:

[0053] Step S201, providing a single cell, wherein the single cell includes an anode plate, a membrane electrode, and a cathode plate stacked in sequence;

[0054] Specifically, the anode plate and the cathode plate are made of a conductive material (such as metal or graphite), the membrane electrode is located between the anode plate and the cathode plate and bonded together, a hydrogen flow field is formed between the anode plate and the membrane electrode, and an air (or oxygen) flow field is formed between the cathode plate and the membrane electrode, and a sealing ring is also provided between the anode plate and the cathode plate, and between the cathode plate and the membrane electrode, so as to seal the hydrogen flow field between the anode plate and the membrane electrode, and the oxygen flow field between the cathode plate and the membrane electrode. At the same time, in order to facilitate gas dispersion, both the anode plate and the cathode plate have arranged flow channels so as to evenly distribute the reaction gas on both sides of the membrane electrode while conducting electricity. Exemplarily, the flow channels of the anode plate and the cathode plate can be straight, serpentine or round-shaped flow channels.

[0055] The membrane electrode mainly includes a proton exchange membrane, an anode catalyst layer, a cathode catalyst layer, an anode gas diffusion layer, and a cathode gas diffusion layer. When hydrogen gas introduced into the anode plate reaches the anode catalyst layer through the anode gas diffusion layer, the hydrogen reacts after catalysis and produces hydrogen ions. The hydrogen ions pass through the proton exchange membrane and enter one side of the cathode plate, where they react with oxygen on the cathode side to form water, generating electricity during the above-mentioned redox reaction. For example, the proton exchange membrane can be a perfluorosulfonic acid membrane, a partially fluorinated polymer proton exchange membrane, a composite proton exchange membrane, or a non-fluorinated polymer proton exchange membrane.

[0056] Step S202: applying a plurality of preset test pressures to the single cells respectively, and obtaining a plurality of test compressions corresponding to the plurality of preset test pressures, wherein the preset test pressures correspond to the test compressions in a one-to-one manner;

[0057] After applying a preset test pressure to a single cell, the cell assembly deforms under pressure, such as compression of the sealing ring and compression of the carbon paper serving as the anode and cathode gas diffusion layers. This reduces the overall thickness of the cell. The test compression of the cell can be obtained by measuring the change in thickness. Specifically, the test compression of the cell can be measured using a thickness detection sensor. For example, a laser sensor or ultrasonic sensor can be used to first measure the initial thickness of the cell, and then measure the thickness of the cell after compression, thereby calculating the test compression of the cell.

[0058] In some embodiments of the present application, multiple preset test pressures may refer to a collection of multiple different pressures, such as 0.1F, 0.2F...1F, where F is the maximum pressure value, so as to facilitate the measurement of the test compression of the single cell under different pressure conditions, so that the single cell can adapt to the stack pressure of different fuel cells, and is conducive to judging whether the compression change curve corresponding to the single cell during the compression process meets the requirements.

[0059] Step S203 , judging whether the single battery is qualified according to a plurality of preset test pressures and a plurality of test compression amounts.

[0060] After obtaining the test compression, the qualification of the single cell can be determined based on multiple preset test pressures and multiple test compressions. In some embodiments of the present application, the preset compression and test compression corresponding to the stacking pressure can be determined. The preset compression is the optimal compression that indicates the qualification of the single cell under the stacking pressure. The stacking pressure is equal to a preset test pressure. Then, based on the preset compression and test compression, the qualification of the single cell can be determined. For example, if the preset compression of the single cell under the preset test pressure is 0.1mm, and the test compression of the single cell during this compression process is 0.15mm, which exceeds the fluctuation range of 20% of the preset compression, the single cell can be determined to be unqualified. For another example, if the preset compression of the single cell under the preset test pressure is 0.2mm, and the test compression of the single cell during this compression process is 0.19mm, which does not exceed the fluctuation range of 20% of the preset compression, the single cell can be determined to be qualified.

[0061] In the embodiment of the present application, a preset test pressure is applied to a single cell and the test compression of the single cell is measured. Ultimately, the qualification of the single cell is determined based on the preset test pressure and the test compression, thereby screening out single cells whose compression meets the requirements under the preset test pressure. When constructing a fuel cell stack, single cells that meet the requirements can be stacked, and after applying a stacking pressure to multiple single cells, the overall size of the fuel cell stack can be controlled, ensuring that the size of the stack after compression under the preset stacking force still meets the design value.

[0062] It is understandable that whether a single cell battery is qualified can also be determined by judging the compression rate. For example, in some embodiments of the present application, the single cell battery testing method further includes:

[0063] Determine the test compression rate of the single cell according to the initial thickness of the single cell and the test compression amount;

[0064] Determine whether the test compression rate meets the requirements to determine whether the single battery is qualified.

[0065] For example, the initial thickness of the single cell is 3 mm, and its corresponding test compression rate is 0.3 mm, then the test compression rate of the single cell is 10%. When the qualified compression rate corresponding to the single cell is 10%, it can be judged that the single cell is qualified; otherwise, it can be judged that the single cell is unqualified.

[0066] In some other embodiments of this application, see Figure 3 , Figure 3 A schematic diagram of a process for determining whether a single battery is qualified is shown in the present application, wherein determining whether a single battery is qualified includes:

[0067] Step S301, determining a compression variation curve of a single battery according to a plurality of preset test pressures and a plurality of test compression amounts;

[0068] Step S302 , judging whether the single cell is qualified according to the compression change curve and the preset change curve, wherein the preset change curve is the optimal compression change curve indicating that the single cell is qualified under multiple preset test pressures.

[0069] In the above embodiment, since different preset test pressures have different pressure values, applying the preset test pressures to the individual cells can determine the test compression corresponding to the preset test pressures for the individual cells, and ultimately, a compression change curve correlating the preset test pressures and the test compression for the individual cells can be obtained. Since the preset change curve represents the optimal compression change curve that indicates a qualified individual cell under multiple preset test pressures, the compression change curve can be compared with the preset change curve to determine whether all individual cells have passed under multiple preset test pressures, thereby ensuring that the individual cells are adaptable to different fuel cell stack pressures. For example, the compression change curve and the preset change curve can be determined to determine whether they overlap, thereby determining whether the individual cells have passed.

[0070] In some other embodiments of this application, see Figure 4 , Figure 4 Another flow chart of determining whether a single cell current is qualified in an embodiment of the present application is shown, wherein determining whether a single cell is qualified includes:

[0071] Step S401, determining a maximum compression difference according to the compression variation curve and a preset variation curve;

[0072] In the above embodiment, the maximum compression difference refers to the maximum difference in compression under a certain preset test pressure between the compression change curve and the preset change curve. For example, at the preset test pressure of 3Mpa, the difference in compression between the compression change curve and the preset change curve is the largest, wherein the corresponding test compression in the compression change curve under the preset test pressure of 3Mpa is 0.22mm, and the corresponding ideal compression in the preset change curve under the preset test pressure of 3Mpa is 0.30mm, then the maximum maximum compression difference is 0.08mm.

[0073] Step S402, integrating the compression change curve and the preset change curve to determine an integral difference between the compression change curve and the preset change curve;

[0074] The integral difference refers to the difference in area enclosed by the compression change curve and the preset change curve in the same coordinate system. The integral difference can reflect the degree of overlap between the compression change curve and the preset change curve as a whole. When the integral difference is larger, the degree of overlap between the compression change curve and the preset change curve is smaller; conversely, when the integral difference is smaller, the degree of overlap between the compression change curve and the preset change curve is greater.

[0075] It can be understood that the integral difference value can be obtained by performing integration operations on the compression change curve and the preset change curve within the same preset test pressure range (for example, 2 MPa to 10 MPa), and then taking the difference.

[0076] Step S403 : judging whether the single battery is qualified according to the maximum compression difference and the integral difference.

[0077] Since the maximum compression difference locally reflects the gap between the actual compression of the single cell and the ideal compression, and the integral difference reflects the gap between the actual compression of the single cell and the ideal compression as a whole, the maximum compression difference and the integral difference are combined to judge whether the single cell is qualified, which can make a more comprehensive and integrated judgment on the single cell.

[0078] In some embodiments of the present application, after determining whether a single cell is qualified by comparing the compression change curve with a preset change curve, the compression change curve can be stored to facilitate preservation of the single cell pressure test data and retrieval during subsequent stacking. Specifically, the compression change curve can be stored in a storage device. It is understood that compression data can also be stored in a storage device.

[0079] It is worth noting that the above content on the single cell battery testing method is intended to clearly illustrate the implementation verification process of this application. Under the guidance of this application, those skilled in the art can also make equivalent modified designs. For example, the compression rate of the single cell battery under different preset test pressures can be calculated separately, and whether the single cell battery is qualified can be judged by the compression rate curve.

[0080] Furthermore, in order to better implement the single cell testing method in the embodiment of the present application, based on the single cell testing method, the present application also provides a method for preparing a battery stack, see Figure 5 , Figure 5 A schematic flow chart of a method for preparing a battery stack in an embodiment of the present application is shown, wherein the method for preparing a battery stack includes:

[0081] Step S501, providing a preset number of single cells that have passed the test by any of the test methods described in the above embodiments;

[0082] Step S502 : stacking a preset number of single cells in sequence, and applying a stacking pressure to the stacked single cells to form a battery stack with a preset size.

[0083] During the fuel cell stacking process, since each single cell has passed the test method and its compression amount under the stacking pressure is known, the stacked single cells can be formed into a stack with a preset size under the action of the stacking pressure, thereby ensuring the controllability of the size of the stack. In some embodiments of the present application, in the process of applying the stacking pressure to the stacked single cells for stacking, the stacking pressure gradually increases. In some embodiments of the present application, for example, for an embodiment in which the preset test pressure is a single pressure, the stacking pressure is equal to the preset test pressure. In some other embodiments of the present application, for example, for an embodiment in which the preset test pressure includes multiple preset test pressures, the stacking pressure is equal to one of the preset test pressures.

[0084] Furthermore, in order to more accurately control the size of the battery stack, refer to Figure 6 , Figure 6 Another schematic flow chart of a method for preparing a fuel cell stack in an embodiment of the present application is shown, wherein the method for preparing a fuel cell stack includes:

[0085] Step S601, providing a plurality of single cells that have passed the test by the test method described in any of the above embodiments;

[0086] Step S602: Select a preset number of cells from a plurality of cells. Different cells have different compression amounts under stacking pressure, and the sum of the compression amounts of the cells, the original size of the cells, and the preset size satisfy the following relationship:

[0087] H=n*h-h0

[0088] Wherein, H is the preset size of the battery stack after compression, n is the preset number, h is the original size of the single cell, and h0 is the sum of the compression amounts of the single cells.

[0089] Step S603 , stacking a preset number of single cells in sequence along a preset direction according to the compression amount, wherein the compression amount of the stacked single cells increases in sequence along the preset direction;

[0090] Step S604 : applying a stacking pressure to the stacked single cells for stacking, wherein the direction of the stacking pressure is opposite to the preset direction.

[0091] In the above embodiment, since the sum of the compression amounts of the single cells, the original dimensions of the single cells, and the preset dimensions satisfy the above relationship, it is possible to ensure that the battery stack reaches the preset dimensions more accurately after compression, which is beneficial to improving the accuracy of the dimensions of the battery stack after compaction. At the same time, since a preset number of single cells are stacked in sequence along a preset direction according to the compression amount, and the direction of the compaction pressure is opposite to the preset direction, as the compaction pressure gradually increases during the compaction process, the single cells with a relatively large compression amount are first compressed to a certain thickness. In other words, the thickness change of the battery stack mainly occurs at the end where the pressure is applied, and after the pressure increases, the single cells of the battery stack as a whole simultaneously undergo a corresponding compression process, which is beneficial to ensuring the stability of the compaction process. During the entire compaction process, the single cells in the battery stack are less likely to slide relative to each other.

[0092] Exemplarily, the preset direction may be parallel to the horizontal plane; or, the preset direction may be perpendicular to the horizontal plane.

[0093] Furthermore, to better implement the method for preparing the battery stack in the embodiments of this application, the present application also provides a fuel cell, which includes a battery stack prepared by the method described in any of the above embodiments. Because the fuel cell in the embodiments of this application includes the battery stack manufactured in the above embodiments, it has all the beneficial effects of the battery stack in the above embodiments and will not be further described here.

[0094] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, please refer to the detailed description of other embodiments above and will not be repeated here.

[0095] The basic concepts have been described above. It will be apparent to those skilled in the art that the detailed disclosure above is merely illustrative and does not limit the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and amendments to the present application. Such modifications, improvements, and amendments are suggested in the present application and remain within the spirit and scope of the exemplary embodiments of the present application.

[0096] At the same time, this application uses specific terms to describe the embodiments of this application. For example, "one embodiment," "an embodiment," and / or "some embodiments" refer to a certain feature, structure, or characteristic related to at least one embodiment of this application. Therefore, it should be emphasized and noted that "one embodiment," "an embodiment," or "an alternative embodiment" mentioned twice or multiple times in different locations in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of this application may be appropriately combined.

[0097] Similarly, it should be noted that, in order to simplify the presentation of this application and thus facilitate understanding of one or more embodiments of the invention, the foregoing descriptions of the embodiments of this application sometimes combine multiple features into a single embodiment, figure, or description thereof. However, this disclosure method does not mean that the subject matter of this application requires more features than those recited in the claims. In fact, an embodiment may have fewer features than all of the features of a single embodiment disclosed above.

[0098] In some embodiments, numbers are used to describe the quantity of components and attributes. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise stated, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the description and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of the present application are approximate values, in specific embodiments, the settings of such numerical values ​​are as accurate as possible within the feasible range.

[0099] Each patent, patent application, patent application publication, and other materials, such as articles, books, specifications, publications, and documents, cited in this application is hereby incorporated by reference in its entirety, except for any application history that is inconsistent with or conflicts with this application, and excluding any document (currently or subsequently appended to this application) that limits the broadest scope of the claims of this application. It should be noted that if the descriptions, definitions, and / or terminology used in the accompanying materials are inconsistent with or conflict with the content of this application, the descriptions, definitions, and / or terminology used in this application will control.

[0100] The above is a detailed introduction to a single cell testing method, a stack preparation method, and a fuel cell provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A method for preparing a fuel cell stack, characterized in that: include: Provide multiple single cells that have passed the single cell test method; A preset number of single cells are selected from a plurality of single cells, wherein different single cells have different compression amounts under a stacking pressure, and the sum of the compression amounts of the single cells, the original size of the single cells, and the preset size satisfy the following relationship: H=n*h-h0 Wherein, H is the preset size of the battery stack after compression, n is the preset number, h is the original size of the single battery, and h0 is the sum of the compression amounts of the single batteries; The single cell testing method comprises: A single cell is provided, wherein the single cell comprises an anode plate, a membrane electrode, and a cathode plate stacked and fixed in sequence; Applying a plurality of preset test pressures to the single cells respectively, and obtaining a plurality of test compressions corresponding to the plurality of preset test pressures, wherein the preset test pressures correspond to the test compressions in a one-to-one manner; Determining whether the single battery is qualified according to the multiple preset test pressures and the multiple test compression amounts; A preset number of the single cells are stacked in sequence, and a stacking pressure is applied to the stacked single cells to form a battery stack having the preset size, wherein the stacking pressure is equal to one of the preset test pressures.

2. The method for preparing a fuel cell stack according to claim 1, wherein: The step of judging whether the single battery is qualified according to the preset test pressure and the test compression amount includes: Determining a compression variation curve of the single battery according to the plurality of preset test pressures and the plurality of test compression amounts; Whether the single cell is qualified is determined based on the compression change curve and a preset change curve, wherein the preset change curve is an optimal compression change curve indicating that the single cell is qualified under the multiple preset test pressures.

3. The method for preparing a fuel cell stack according to claim 2, wherein: The step of judging whether the single battery is qualified according to the compression change curve and the preset change curve includes: determining a maximum compression difference according to the compression variation curve and the preset variation curve; Integrating the compression change curve and the preset change curve to determine an integral difference between the compression change curve and the preset change curve; Whether the single battery is qualified is determined according to the maximum compression difference and the integral difference.

4. The method for preparing a fuel cell stack according to claim 1, wherein: The step of judging whether the single battery is qualified according to the plurality of preset test pressures and the plurality of test compression amounts includes: Determining a preset compression amount and a test compression amount corresponding to a stacking pressure, wherein the preset compression amount is an optimal compression amount that indicates that the single battery is qualified under the stacking pressure, and the stacking pressure is equal to a preset test pressure; Whether the single battery is qualified is determined based on the preset compression amount and the test compression amount.

5. The method for preparing a fuel cell stack according to claim 1, wherein: The step of stacking a preset number of the single cells in sequence and applying a stacking pressure to the stacked single cells to form a battery stack having a preset size includes: Stacking a preset number of the single batteries in sequence along a preset direction according to the compression amount, wherein the compression amount of the stacked single batteries increases in sequence along the preset direction; A stacking pressure is applied to the stacked single cells for stacking, wherein the direction of the stacking pressure is opposite to the preset direction.

6. The method for preparing a fuel cell stack according to claim 5, wherein: The preset direction is parallel to the horizontal plane; or The preset direction is perpendicular to the horizontal plane.

7. The method for preparing a fuel cell stack according to claim 5, wherein: During the process of applying a stacking pressure to the stacked single cells, the stacking pressure gradually increases.

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