A fuel cell stack repair method and system

Abstract

A fuel cell stack repair method and system, belonging to the field of battery repair, includes collecting the first performance parameter and historical operating parameters of the old core, and the second performance parameter of the faulty battery in the old core, wherein the first performance parameter and the second performance parameter both include resistance and height values; obtaining the battery depreciation degree according to the historical operating parameters; selecting a replacement battery with the same second performance parameter for the faulty battery; pre-pressing the replacement battery according to the battery depreciation degree so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery; after forming a new core based on the pre-pressed replacement battery, the new core is pressed as a whole until the new core height and the internal resistance of the stack are consistent with those of the old core. This application selects a replacement battery with the same performance parameters as the faulty battery and pre-presses the replacement battery so that the battery sealing line before and after the repair remains consistent, thereby ensuring the sealing and repair effect of the stack.

Description

Technical Field

[0001] The present application relates to the field of battery repair, and specifically to a fuel cell stack repair method and system. Background Art

[0002] Fuel cell stacks are generally composed of dozens to hundreds of single cells connected in series in terms of output power. Each cell is composed of a membrane electrode assembly (MEA) and bipolar plates on both sides. The membrane electrode and bipolar plates are both provided with three-cavity holes, including a hydrogen cavity, an air cavity, and a water cavity, and sealing lines are provided around the three-cavity holes.

[0003] When assembling a fuel cell stack, all the cells are stacked together to form a core. The three-cavity holes between any two adjacent cells are aligned to form a three-cavity flow channel of the fuel cell stack, and the sealing lines around the holes are used to seal the contact points of the sealing lines, thereby achieving the sealing of the three-cavity flow channel. Then, positive and negative current collectors are first installed on both sides of the core, and then insulation and end plates are installed. After further installing the positive and negative electrodes of the battery, they are fixed and packaged using a fixing device.

[0004] In the actual use of fuel cell stacks, individual cells are prone to failure due to factors such as operating conditions and component quality. Once a single cell fails, the fuel cell stack cannot be used any further, otherwise more cells will be damaged, resulting in irreversible damage.

[0005] There is no in-depth research on the repair of fuel cell stack faults in the industry. Generally, the faulty battery is directly replaced, that is, the membrane electrode and bipolar plate of the faulty single cell are removed from the fuel cell stack and directly replaced with new materials. This method can solve the failure problem of a single cell, but it will also bring some additional problems. For example, when the fuel cell stack is first assembled, all the single cells are stacked together to form a core, and the core is pressed as a whole. After pressing, there is extrusion stress between the cells. After fixing and packaging with a fixing device, the extrusion stress still exists. With the use of the fuel cell stack, the volume of the single cell will shrink, the extrusion stress will also change, and the contact surface between the cells, especially the sealing line contact surface, will change. Directly using new materials to replace the faulty battery can easily lead to sealing adaptation problems between the new material and the old batteries on both sides of the faulty battery, and poor sealing can easily lead to leakage problems.

[0006] Therefore, how to better repair the fuel cell stack is a technical problem that urgently needs to be solved. Summary of the invention

[0007] The present application provides a fuel cell stack repair method and system, which can solve the technical problem in the prior art that the sealing and various performances of a fuel cell stack cannot meet expectations after a faulty cell is repaired.

[0008] In a first aspect, an embodiment of the present application provides a fuel cell stack repair method, the method comprising:

[0009] Collecting first performance parameters and historical operating parameters of the old core and second performance parameters of the faulty battery in the old core, wherein the first performance parameter and the second performance parameter both include resistance value and height value, and the historical operating parameters include battery stack operation time, number of times the battery stack is disassembled and assembled, battery stack performance attenuation rate, whole stack internal resistance increase rate, and three-cavity flow resistance increase rate;

[0010] According to the historical operating parameters, the battery depreciation degree is obtained; a replacement battery with the same second performance parameter is selected for the faulty battery; the replacement battery is pre-pressed according to the battery depreciation degree, so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery, and the battery depreciation degree is positively correlated with the pre-pressing degree;

[0011] After a new core is formed based on the replacement cells after pre-pressing, the new core is pressed as a whole until the height of the new core is consistent with that of the old core to determine whether the internal resistance of the new stack is not greater than that of the old stack. If so, the core is packaged; if not, pressing continues until the internal resistance of the new stack is no greater than that of the old stack.

[0012] In combination with the first aspect, in one implementation, the resistance value in the first performance parameter is the internal resistance of the fuel cell stack, and the height value in the first performance parameter is the core height.

[0013] In combination with the first aspect, in one implementation, the resistance value in the second performance parameter is the contact resistance, and the height value in the second performance parameter is the battery height.

[0014] In combination with the first aspect, in one implementation, the second performance parameter also includes battery length and battery width.

[0015] In combination with the first aspect, in one implementation, the method includes:

[0016] Before removing the faulty battery from the old core, collecting the first performance parameter;

[0017] The second performance parameter is collected after the faulty battery is removed from the existing core.

[0018] In combination with the first aspect, in one embodiment, pre-pressing the replacement battery according to the battery depreciation degree so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery specifically includes the following steps:

[0019] Set the pre-pressing pressure and pre-pressing time according to the battery depreciation degree;

[0020] The replacement battery is pre-pressed according to the pre-pressing pressure and the pre-pressing time so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery.

[0021] In combination with the first aspect, in one implementation, the pre-pressing time includes a pressurizing time, a pressure holding time, and a pressure stabilizing time.

[0022] In combination with the first aspect, in one implementation, when the new core is pressed as a whole, it is pressed in a positional manner according to the height of the old core;

[0023] When it is determined that the internal resistance of the new battery stack is greater than the internal resistance of the old battery stack, pressure pressing is used according to the internal resistance of the old battery stack.

[0024] In combination with the first aspect, in one implementation, the method further includes:

[0025] When the internal resistance of the new stack is not greater than that of the old stack, determine whether the new three-cavity flow resistance is not greater than the expected value. If so, package the core; if not, continue to press-fit until the new three-cavity flow resistance is not greater than the expected value.

[0026] In a second aspect, an embodiment of the present application provides a fuel cell stack repair system, the fuel cell stack repair system comprising:

[0027] A data acquisition module, which is used to collect first performance parameters and historical operating parameters of the old core, and second performance parameters of the faulty battery in the old core, wherein the first performance parameter and the second performance parameter both include resistance and height values, the second performance parameter includes battery size and contact resistance, and the historical operating parameters include battery stack operation time, number of times the battery stack is disassembled and assembled, battery stack performance attenuation rate, whole stack internal resistance increase rate, and three-cavity flow resistance increase rate;

[0028] A battery replacement module is used to obtain the battery depreciation degree based on historical operating parameters; select a replacement battery with the same second performance parameter as the faulty battery; pre-press the replacement battery according to the battery depreciation degree so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery, and the battery depreciation degree is positively correlated with the pre-pressing degree; and is also used to form a new core based on the pre-pressed replacement battery, and then press the new core as a whole until the height of the new core is consistent with the height of the old core, and determine whether the internal resistance of the new battery stack is not greater than the internal resistance of the old battery stack. If so, the core is packaged; if not, the pressing is continued until the internal resistance of the new battery stack is not greater than the internal resistance of the old battery stack.

[0029] The beneficial effects brought by the technical solution provided by the embodiments of the present application include:

[0030] By collecting the first performance parameters of the old core containing the faulty battery, the battery depreciation degree is calculated, and by collecting the second performance parameters of the faulty battery, a replacement battery with the same expected performance parameters is selected, and the replacement battery is pre-pressed according to the depreciation degree, so that the resistance value, height value, and sealing line deformation of the replacement battery are consistent with the faulty battery, and the pre-pressed replacement battery and other batteries except the faulty battery in the old core are stacked together to form a new core, and the new core is pressed as a whole to make the core height of the new core consistent with that of the old core, so that the extrusion stress between each battery in the new and old cores is consistent. At this time, the performance parameters of the new core are collected to determine whether the internal resistance of the new core does not exceed that of the old core. If so, it means that all parameters of the new core except the sealing have reached the level before repair, and packaging can be performed at this time. If not, it means that some parameters of the new core except the sealing have not reached the level before repair, and pressing continues at this time, and then it is determined whether to package according to the performance test results, so as to ensure that the parameters of the repaired new core meet expectations and improve the repair effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a flow chart of an embodiment of a fuel cell stack repair method of the present application;

[0032] Figure 2 This is a schematic diagram of the functional modules of an embodiment of a fuel cell stack repair system of the present application. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0034] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0035] In a first aspect, an embodiment of the present application provides a fuel cell stack repair method.

[0036] In one embodiment, referring to Figure 1 , Figure 1 This is a flow chart of an embodiment of the fuel cell stack repair method of the present application. Figure 1 As shown, the fuel cell stack repair method includes:

[0037] Step S1, collecting the first performance parameters and historical operating parameters of the old core, and the second performance parameters of the faulty battery in the old core, the first performance parameter and the second performance parameter both include resistance and height values, the second performance parameter includes battery size and contact resistance, and the historical operating parameters include battery stack operation time, number of times the battery stack is disassembled and assembled, battery stack performance attenuation rate, whole stack internal resistance increase rate, and three-cavity flow resistance increase rate.

[0038] Step S2: Obtain the battery depreciation degree according to the historical operating parameters. Select a replacement battery with the same second performance parameter for the faulty battery. Pre-press the replacement battery according to the battery depreciation degree so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery, and the battery depreciation degree is positively correlated with the pre-pressing degree.

[0039] Step S3: After a new core is formed based on the replacement cells after pre-pressing, the new core is pressed as a whole until the height of the new core is consistent with the height of the old core, and it is determined whether the internal resistance of the new battery stack is not greater than the internal resistance of the old battery stack. If so, the core is packaged. If not, the pressing is continued until the internal resistance of the new battery stack is not greater than the internal resistance of the old battery stack.

[0040] In this embodiment, by collecting the first performance parameter of the old core containing the faulty battery, the battery depreciation degree is calculated, and by collecting the second performance parameter of the faulty battery, a replacement battery with the same expected performance parameter is selected, and the replacement battery is pre-pressed according to the depreciation degree, so that the resistance value, height value, and sealing line deformation of the replacement battery are consistent with those of the faulty battery, and the pre-pressed replacement battery and other batteries in the old core except the faulty battery are stacked together to form a new core, and the new core is pressed as a whole to make the core height of the new core consistent with that of the old core, so that the extrusion stress between each battery in the new and old cores is consistent. At this time, the performance parameters of the new core are collected to determine whether the internal resistance of the new core does not exceed that of the old core. If so, it means that all parameters of the new core except the sealing have reached the level before repair, and packaging can be performed at this time. If not, it means that some parameters of the new core except the sealing have not reached the level before repair, and pressing continues at this time, and then it is determined whether to package according to the performance test results, thereby ensuring that the parameters of the repaired new core meet expectations and improving the repair effect.

[0041] In a specific embodiment, the old core of the fuel cell stack is packaged by a tie rod fixation method. The old core contains multiple single cells, each of which includes a membrane electrode and two bipolar plates on both sides of the membrane electrode. Each membrane electrode and each bipolar plate are provided with three-cavity holes and sealing lines around the three-cavity holes. The sealing lines can be made of elastic materials such as rubber. When multiple single cells are stacked, a structure of alternating stacking of membrane electrodes and bipolar plates is formed. The stacking height is the core height. The holes between adjacent single cells and inside the single cells need to be aligned. After the holes of all cells are aligned, they are spliced ​​to form the three cavities of the stack. The sealing lines of adjacent membrane electrodes and bipolar plates are in contact and squeezed with each other after the holes are aligned, thereby achieving the sealing of the three cavities of the stack. Sealing plates and end plates will be set at both ends of the core. One end plate is connected to the three cavities, and the other end plate is a blind plate for sealing the three cavities. After the core is pressed as a whole, a number of tie rods are arranged in the height direction of the core to fix and package the fuel cell stack, sealing plates and end plates together according to the height of the core after the overall pressing to form a fuel cell stack.

[0042] After a fuel cell stack has been used for a period of time, the volume of each battery will be reduced to a certain extent, the extrusion stress between the batteries will be reduced, and the sealing lines on each battery will be deformed after long-term extrusion. Since the three-cavity flow channel structure is relatively complex, the corresponding sealing line structure designed around the three-cavity flow channel is also relatively complex. Therefore, after the sealing line is deformed, it is difficult to directly measure the deformation amount at each position of the sealing line. Specifically, when the faulty battery is installed on the core, the sealing line of the faulty battery is blocked by the batteries on both sides and cannot be directly measured. In addition, when the faulty battery is installed on the core, the batteries on both sides squeeze it. If the faulty battery is removed from the core, the squeezing force on both sides disappears. Before and after removal, the sealing line on the faulty battery will still be deformed. After the faulty battery is removed from the core, the deformation of the sealing line can be directly measured, but the result is inconsistent with when it is installed on the core.

[0043] Based on the above reasons, when a faulty battery appears in the core, the first performance parameters and historical operating parameters of the old core, as well as the second performance parameters of the faulty battery in the old core are first collected. The above first performance parameters and second performance parameters both include resistance values ​​and height values. The above historical operating parameters include the stack operation time, the number of times the stack is disassembled and assembled, the stack performance attenuation rate, the increase rate of the internal resistance of the whole stack, and the increase rate of the three-cavity flow resistance.

[0044] Then, a replacement battery with the same resistance and height values ​​as the faulty battery is selected. Since the replacement battery is generally a new battery, its sealing line has not been squeezed. Therefore, the sealing line size of the replacement battery is generally inconsistent with the sealing line size of the faulty battery. If the replacement battery is directly installed in the core, the replacement battery and the batteries on both sides of the original faulty battery will have inconsistent sealing line contact surfaces when they are in contact with each other, which will cause sealing problems. Therefore, the battery depreciation degree is calculated based on the historical operating parameters of the old core, and the replacement battery is pre-pressed according to the battery depreciation degree. The greater the battery depreciation degree, the greater the pre-pressing degree, so that the sealing linear variables of the replacement battery are consistent with the sealing linear variables of the faulty battery when it is installed on the core, ensuring that the replacement battery is installed on the core and the sealing line contact surface with the adjacent battery is consistent.

[0045] The replacement battery after pre-compression is restacked with other batteries in the old core except the faulty battery to form a new core, and the new core is pressed as a whole to make the core height of the new core consistent with that of the old core, so that the extrusion stress between each battery in the new and old cores is consistent. At this time, the performance parameters of the new core are collected to determine whether the internal resistance of the new core does not exceed that of the old core. If so, it means that all parameters of the new core except the sealing have reached the level before repair, and packaging can be carried out at this time. If not, it means that some parameters of the new core except the sealing have not reached the level before repair, and pressing continues at this time, and then determine whether to package based on the performance test results, so as to ensure that the parameters of the repaired new core meet expectations and improve the repair effect.

[0046] In some other embodiments, continued press-installation of the core height will cause it to drop below the height before disassembly, which can be solved by using an insulating film to raise the height. The specific implementation method is to add an insulating film with a thickness of 0.1 mm between the blind-end current collecting plate and the blind-end end plate, and make a reasonable selection based on the drop height value until the core height remains consistent with that before disassembly, and the internal resistance value is not greater than that of the old fuel cell stack. In this way, the original packaging structure of the fuel cell stack, such as the tie rod, can be used.

[0047] In some other embodiments, before disassembling the faulty battery, the first performance parameter of the old battery stack is measured and recorded, and at the same time, the hydrogen chamber, cavity, and water chamber of the old battery stack are purged with heated nitrogen on a test bench. The purging time is based on the insulation performance of the positive and negative terminals of the old battery stack to the shell. When the insulation performance reaches the target value, the purging is stopped.

[0048] When disassembling a faulty battery, first mark the position of the faulty battery before disassembling the device, then take out the faulty battery, and measure the second performance parameter of the faulty battery.

[0049] During the pre-pressing process, the battery is positioned to prevent abnormal slippage during the press-fitting process. The positioning reference is consistent with the press-fitting mechanism to reduce positioning deviation.

[0050] The contact resistance and battery height of the replacement battery after pre-pressing may have a certain range of error with the faulty battery. For example, if the error does not exceed 10%, it can be considered that the pre-pressing has achieved expectations.

[0051] Furthermore, in one embodiment, the resistance value in the above-mentioned first performance parameter is the internal resistance of the fuel cell stack, and the height value in the above-mentioned first performance parameter is the core height.

[0052] In this embodiment, the internal resistance of the battery stack is measured before and after the faulty battery is replaced, so as to ensure that the internal resistance of the entire stack is consistent before and after the faulty battery is replaced.

[0053] Furthermore, in one embodiment, the resistance value in the above second performance parameter is the contact resistance, and the height value in the above second performance parameter is the battery height.

[0054] In this embodiment, since the faulty battery is squeezed by adjacent batteries when installed on the core, its contact resistance is selected to be collected. The contact resistance is related to pressure and is collected by applying different pressures multiple times, which can more accurately reflect the resistance value of the battery.

[0055] Furthermore, in one embodiment, the second performance parameter also includes battery length and battery width.

[0056] In this embodiment, when selecting a replacement battery, a replacement battery with the same size is selected according to the length, width and height of the faulty battery to improve the repair efficiency.

[0057] Furthermore, in one embodiment, the method includes:

[0058] Before removing the faulty battery from the old core, the first performance parameter is collected.

[0059] After the faulty battery is removed from the existing core, the above-mentioned second performance parameter is collected.

[0060] In this embodiment, before the faulty battery is removed, the internal resistance of the battery stack and the core height are collected, so that after the replacement battery is installed on the core, the new core is measured to determine whether the repair is as expected.

[0061] After the faulty battery is removed, the contact resistance and core height are collected to facilitate data collection.

[0062] Further, in one embodiment, the above-mentioned pre-pressing of the replacement battery according to the battery depreciation degree so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery specifically includes the following steps:

[0063] Set the pre-pressing pressure and pre-pressing time according to the battery depreciation degree.

[0064] The replacement battery is pre-pressed according to the pre-pressing pressure and the pre-pressing time so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery.

[0065] The pre-pressing time includes pressurizing time, pressure holding time, and pressure stabilizing time.

[0066] In this embodiment, position press-fitting is to control the target position when press-fitting is completed, and pressure press-fitting is to control the pressure during press-fitting. During pre-pressing, the first stage pressure mode is based on the calculated target pressure, and the pressurization rate is set to 0.05KN / second to obtain the pressurization time. After reaching the target pressure, the pressure is maintained, which is determined by the set pressure maintenance time. During this process, the pressure is always maintained at the target pressure value, and the stress caused by the battery deformation is slowly eliminated during the pressure maintenance process. After the pressure maintenance is completed, it switches to the second stage position control mode. In this stage, the pre-pressing position is kept unchanged, and the deformation caused by the pre-pressing pressure of the replacement battery tends to be stable. At this time, the pressure will slowly decrease from the pre-pressing pressure until it stabilizes. The time required for the pressure to drop to 90% of the pre-pressing pressure during the pressure stabilization period shall prevail.

[0067] Through pre-compression, the pressure state of the battery sealing line basically reaches the level before replacement, thereby improving the compatibility with adjacent batteries and reducing the risk of leakage caused by poor sealing.

[0068] Furthermore, in one embodiment, when the new core is press-fitted as a whole, it is press-fitted in a positional manner according to the height of the old core.

[0069] When it is determined that the internal resistance of the new battery stack is greater than the internal resistance of the old battery stack, pressure pressing is used according to the internal resistance of the old battery stack.

[0070] In a second aspect, an embodiment of the present application also provides a fuel cell stack repair system.

[0071] In one embodiment, referring to Figure 2 , Figure 2 This is a functional module diagram of an embodiment of a fuel cell stack repair system of the present application. Figure 2 As shown, the fuel cell stack repair system includes:

[0072] Data acquisition module 1 is used to collect the first performance parameters and historical operating parameters of the old core, and the second performance parameters of the faulty battery in the old core, the first performance parameters and the second performance parameters both include resistance and height values, the second performance parameters include battery size and contact resistance, and the historical operating parameters include battery stack operation time, number of times the battery stack is disassembled and assembled, battery stack performance attenuation rate, whole stack internal resistance increase rate, and three-cavity flow resistance increase rate.

[0073] The battery replacement module 2 is used to obtain the battery depreciation degree based on historical operating parameters. A replacement battery with the same second performance parameter is selected for the faulty battery. The replacement battery is pre-pressed according to the battery depreciation degree so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery, and the battery depreciation degree is positively correlated with the pre-pressing degree. It is also used to form a new core based on the replacement battery after pre-pressing, and then press the new core as a whole until the height of the new core is consistent with the height of the old core, and judge whether the internal resistance of the new battery stack is not greater than the internal resistance of the old battery stack. If so, the core is packaged. If not, continue to press until the internal resistance of the new battery stack is no greater than the internal resistance of the old battery stack.

[0074] Among them, the functional implementation of each module in the above-mentioned fuel cell stack repair system corresponds to the various steps in the above-mentioned fuel cell stack repair method embodiment, and its functions and implementation processes will not be repeated here one by one.

[0075] In this embodiment, by collecting the first performance parameter of the old core containing the faulty battery, the battery depreciation degree is calculated, and by collecting the second performance parameter of the faulty battery, a replacement battery with the same expected performance parameter is selected, and the replacement battery is pre-pressed according to the depreciation degree, so that the resistance value, height value, and sealing line deformation of the replacement battery are consistent with the faulty battery, and the pre-pressed replacement battery and other batteries except the faulty battery in the old core are stacked together to form a new core, and the new core is pressed as a whole to make the core height of the new core consistent with that of the old core, so that the extrusion stress between each battery in the new and old cores is consistent. At this time, the performance parameters of the new core are collected to determine whether the internal resistance of the new core does not exceed that of the old core. If so, it means that all parameters of the new core except the sealing have reached the level before repair, and packaging can be performed at this time. If not, it means that some parameters of the new core except the sealing have not reached the level before repair, and pressing continues at this time, and then it is determined whether to package according to the performance test results, thereby ensuring that the parameters of the repaired new core meet expectations and improving the repair effect.

[0076] Furthermore, in one embodiment, the resistance value in the above-mentioned first performance parameter is the internal resistance of the fuel cell stack, and the height value in the above-mentioned first performance parameter is the core height.

[0077] In this embodiment, the internal resistance of the battery stack is measured before and after the faulty battery is replaced, so as to ensure that the internal resistance of the entire stack is consistent before and after the faulty battery is replaced.

[0078] Furthermore, in one embodiment, the resistance value in the above second performance parameter is the contact resistance, and the height value in the above second performance parameter is the battery height.

[0079] In this embodiment, since the faulty battery is squeezed by adjacent batteries when installed on the core, its contact resistance is selected to be collected. The contact resistance is related to pressure and is collected by applying different pressures multiple times, which can more accurately reflect the resistance value of the battery.

[0080] Furthermore, in one embodiment, the second performance parameter also includes battery length and battery width.

[0081] In this embodiment, when selecting a replacement battery, a replacement battery with the same size is selected according to the length, width and height of the faulty battery to improve the repair efficiency.

[0082] Furthermore, in one embodiment, the first performance parameter is collected before the faulty battery is removed from the old core.

[0083] After the faulty battery is removed from the existing core, the above-mentioned second performance parameter is collected.

[0084] In this embodiment, before the faulty battery is removed, the internal resistance of the battery stack and the core height are collected, so that after the replacement battery is installed on the core, the new core is measured to determine whether the repair is as expected.

[0085] After the faulty battery is removed, the contact resistance and core height are collected to facilitate data collection.

[0086] Furthermore, in one embodiment, the pre-pressing pressure and the pre-pressing time are set according to the degree of battery depreciation.

[0087] The replacement battery is pre-pressed according to the pre-pressing pressure and the pre-pressing time so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery.

[0088] The pre-pressing time includes pressurizing time, pressure holding time, and pressure stabilizing time.

[0089] In this embodiment, position press-fitting is to control the target position when press-fitting is completed, and pressure press-fitting is to control the pressure during press-fitting. During pre-pressing, the first stage pressure mode is based on the calculated target pressure, and the pressurization rate is set to 0.05KN / second to obtain the pressurization time. After reaching the target pressure, the pressure is maintained, which is determined by the set pressure maintenance time. During this process, the pressure is always maintained at the target pressure value, and the stress caused by the battery deformation is slowly eliminated during the pressure maintenance process. After the pressure maintenance is completed, it switches to the second stage position control mode. In this stage, the pre-pressing position is kept unchanged, and the deformation caused by the pre-pressing pressure of the replacement battery tends to be stable. At this time, the pressure will slowly decrease from the pre-pressing pressure until it stabilizes. The time required for the pressure to drop to 90% of the pre-pressing pressure during the pressure stabilization period shall prevail.

[0090] Through pre-compression, the pressure state of the battery sealing line basically reaches the level before replacement, thereby improving the compatibility with adjacent batteries and reducing the risk of leakage caused by poor sealing.

[0091] Furthermore, in one embodiment, when the new core is press-fitted as a whole, it is press-fitted in a positional manner according to the height of the old core.

[0092] When it is determined that the internal resistance of the new battery stack is greater than the internal resistance of the old battery stack, pressure pressing is used according to the internal resistance of the old battery stack.

[0093] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0094] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0095] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0096] In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B. "And / or" in the text is only a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0097] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0098] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as mentioned above, and includes a number of instructions for a terminal device to execute the above-mentioned methods of each embodiment of the present application.

[0099] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A fuel cell stack repair method, characterized in that: The method comprises: Collecting first performance parameters and historical operating parameters of the old core and second performance parameters of the faulty battery in the old core, wherein the first performance parameter and the second performance parameter both include resistance value and height value, and the historical operating parameters include battery stack operation time, number of times the battery stack is disassembled and assembled, battery stack performance attenuation rate, whole stack internal resistance increase rate, and three-cavity flow resistance increase rate; According to the historical operating parameters, the battery depreciation degree is obtained; a replacement battery with the same second performance parameter is selected for the faulty battery; the replacement battery is pre-pressed according to the battery depreciation degree, so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery, and the battery depreciation degree is positively correlated with the pre-pressing degree; After a new core is formed based on the replacement cells after pre-pressing, the new core is pressed as a whole until the height of the new core is consistent with that of the old core to determine whether the internal resistance of the new stack is not greater than that of the old stack. If so, the core is packaged; if not, pressing continues until the internal resistance of the new stack is no greater than that of the old stack.

2. The fuel cell stack repair method according to claim 1, characterized in that: The resistance value in the first performance parameter is the internal resistance of the fuel cell stack, and the height value in the first performance parameter is the core height.

3. The fuel cell stack repair method according to claim 1, characterized in that: The resistance value in the second performance parameter is the contact resistance, and the height value in the second performance parameter is the battery height.

4. The fuel cell stack repair method according to claim 1, characterized in that: The second performance parameters also include battery length and battery width.

5. The fuel cell stack repair method according to claim 1, characterized in that: The method comprises: Before removing the faulty battery from the old core, collecting the first performance parameter; The second performance parameter is collected after the faulty battery is removed from the old core.

6. The fuel cell stack repair method according to claim 1, characterized in that: The pre-pressing of the replacement battery according to the battery depreciation degree so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery specifically includes the following steps: Set the pre-pressing pressure and pre-pressing time according to the battery depreciation degree; The replacement battery is pre-pressed according to the pre-pressing pressure and the pre-pressing time so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery.

7. The fuel cell stack repair method according to claim 6, characterized in that: The pre-pressing time includes a pressurizing time, a pressure holding time, and a pressure stabilizing time.

8. The fuel cell stack repair method according to claim 1, characterized in that: When the new core is pressed as a whole, it is pressed in position according to the height of the old core; When it is determined that the internal resistance of the new battery stack is greater than the internal resistance of the old battery stack, pressure pressing is used according to the internal resistance of the old battery stack.

9. The fuel cell stack repair method according to claim 1, characterized in that: The method further comprises: When the internal resistance of the new stack is not greater than that of the old stack, determine whether the new three-cavity flow resistance is not greater than the expected value. If so, package the core; if not, continue to press-fit until the new three-cavity flow resistance is not greater than the expected value.

10. A fuel cell stack repair system, characterized in that: The fuel cell stack repair system comprises: A data acquisition module, which is used to collect first performance parameters and historical operating parameters of the old core, and second performance parameters of the faulty battery in the old core, wherein the first performance parameter and the second performance parameter both include resistance and height values, the second performance parameter includes battery size and contact resistance, and the historical operating parameters include battery stack operation time, number of times the battery stack is disassembled and assembled, battery stack performance attenuation rate, whole stack internal resistance increase rate, and three-cavity flow resistance increase rate; A battery replacement module is used to obtain the battery depreciation degree based on historical operating parameters; select a replacement battery with the same second performance parameter as the faulty battery; pre-press the replacement battery according to the battery depreciation degree so that the sealing line deformation of the replacement battery is consistent with the sealing line deformation of the faulty battery, and the battery depreciation degree is positively correlated with the pre-pressing degree; and is also used to form a new core based on the pre-pressed replacement battery, and then press the new core as a whole until the height of the new core is consistent with the height of the old core, and determine whether the internal resistance of the new battery stack is not greater than the internal resistance of the old battery stack. If so, the core is packaged; if not, the pressing is continued until the internal resistance of the new battery stack is not greater than the internal resistance of the old battery stack.

Images