Power battery pack preprocessing method, device, system and equipment and storage medium

Abstract

The invention relates to a power battery pack preprocessing method, device, system and equipment and a storage medium. The method comprises the following steps: acquiring a target cycle index; the target cycle index is determined by performing current cycle processing and dominant frequency measurement on the sample power battery pack; and pre-processing the target power battery pack according to the target cycle index. According to the invention, the test sample can be subjected to sufficient battery circulation treatment, so that the test effect of structural durability and strength test is improved.

Description

Technical Field

[0001] The present application relates to the technical field of power battery pack pretreatment, and in particular to a power battery pack pretreatment method, device, system, equipment and storage medium. Background Art

[0002] With the development of new energy technology and automobile technology, electric vehicles using power batteries are becoming more and more popular. In the design and manufacturing process of power batteries for electric vehicles, structural durability and strength testing is a very important test.

[0003] At present, before conducting structural durability and strength tests, power battery packs are usually pre-treated with current circulation to eliminate the mechanical stress and strain caused by the power battery pack during assembly. However, there are cases where the current circulation pre-treatment is insufficient and the test sample does not match the actual product status, resulting in poor results in structural durability and strength tests. Summary of the invention

[0004] Based on the above problems, the present application provides a power battery pack pretreatment method, device, system, equipment and storage medium, which can enable the test samples to undergo sufficient battery cycle treatment, thereby improving the test results of structural durability and strength tests.

[0005] In a first aspect, the present application provides a method for preprocessing a power battery pack. The method includes: obtaining a target cycle number; the target cycle number is determined by performing current cycle processing and main frequency measurement on a sample power battery pack; and preprocessing the target power battery pack according to the target cycle number.

[0006] In the technical solution of the embodiment of the present application, when structural durability and strength tests are required, the test samples are pre-processed according to the target number of cycles so that the test samples are consistent with the actual product status, thereby improving the effect of the structural durability and strength tests.

[0007] In some embodiments, obtaining the target number of cycles includes: in the process of performing current cycle processing on the first sample power battery pack, obtaining a plurality of main frequency data obtained by measuring the main frequency of the first sample power battery pack for each preset number of cycles; and determining the target number of cycles according to the change trend of the main frequency data. In the technical solution of the embodiment of the present application, a more reasonable target number of cycles can be determined according to the change trend of the main frequency data with the number of cycles, that is, the target number of cycles can not only make the test sample undergo more sufficient pretreatment, but also save pretreatment time and improve pretreatment efficiency.

[0008] In some embodiments, a plurality of main frequency data obtained by measuring the main frequency of the first sample power battery pack is obtained for a preset number of times per cycle, including: obtaining the main frequency data obtained by measuring the main frequency of the first sample power battery pack by the automotive modal device for a preset number of times per cycle. In the technical solution of the embodiment of the present application, the power battery pack can be directly placed on the elastic suspension of the automotive modal device without the need to use a fixture to fix the power battery pack. Therefore, the influence introduced by the fixture assembly can be eliminated, and subtle main frequency differences can be accurately identified, thereby obtaining more accurate main frequency data.

[0009] In some embodiments, obtaining the main frequency data obtained by measuring the main frequency of the first sample power battery pack by the automobile modal device includes: obtaining the main frequency data obtained by measuring the main frequency of the first sample power battery pack under a preset charge state by the automobile modal device. In the technical solution of the embodiment of the present application, the main frequency data of the first sample power battery pack under different charge states can be obtained, and the target number of cycles can be determined based on the main frequency data under multiple charge states, which can improve the accuracy of the target number of cycles.

[0010] In some embodiments, the method further includes: obtaining expansion force data of the second sample power battery pack during current cycling of the second sample power battery pack; determining the cycle number interval according to the amount of change of the expansion force data with the cycle number; correspondingly, obtaining multiple main frequency data obtained by measuring the main frequency of the first sample power battery pack for each preset number of cycles, including: obtaining multiple main frequency data obtained by measuring the main frequency of the first sample power battery pack for each preset number of cycles within the cycle number interval. In the technical solution of the embodiment of the present application, a more reasonable cycle number interval can be determined according to the expansion force, thereby determining a more reasonable main frequency measurement frequency within the cycle number interval, so that not only the main frequency data can be collected, but also the measurement efficiency of the main frequency data can be improved, thereby improving the efficiency of determining the target cycle number.

[0011] In some embodiments, determining the cycle number interval according to the trend of the expansion force data changing with the cycle number includes: drawing an expansion force change curve according to the expansion force data; when the expansion force change curve is an upward convex curve, determining the cycle number interval according to the inflection point of the upward convex curve. In the technical solution of the embodiment of the present application, the cycle number interval can be determined relatively easily and quickly according to the expansion force change curve, thereby improving the efficiency of determining the target cycle number.

[0012] In some embodiments, the target number of cycles is determined according to the changing trend of the main frequency data, including: determining the candidate number of cycles according to the changing trend of the main frequency data; obtaining the main frequency data of the third sample power battery pack after the candidate number of cycles is processed; if the main frequency data of the third sample power battery pack meets the preset conditions, the candidate number of cycles is determined as the target number of cycles. In the technical solution of the embodiment of the present application, the candidate number of cycles is determined, and the candidate number of cycles is tested using the vibration isolation theory, so that a more reasonable target number of cycles can be determined, thereby performing a more adequate pretreatment of the test samples used in the structural durability and strength tests, and the pretreatment time can also be saved.

[0013] In a second aspect, the present application also provides a power battery pack pretreatment device, the device comprising:

[0014] A number acquisition module is used to obtain a target cycle number; the target cycle number is determined by performing current cycle processing and main frequency measurement on a sample power battery pack;

[0015] The preprocessing module is used to preprocess the target power battery pack according to the target number of cycles.

[0016] In a third aspect, the present application also provides a power battery pack pretreatment system. The power battery pack pretreatment system includes a circulation treatment device, an automobile modal device and a computer device;

[0017] The circulation processing equipment is used to perform current circulation processing on the power battery pack;

[0018] The automotive modal device is used to measure the main frequency of the power battery pack to obtain main frequency data;

[0019] The computer device is used to determine the target number of cycles according to the main frequency data.

[0020] In a fourth aspect, the present application further provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the method described in the first aspect is implemented.

[0021] In a fifth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the method described in the first aspect is implemented.

[0022] In a sixth aspect, the present application further provides a computer program product, including a computer program, which implements the method described in the first aspect when executed by a processor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the optional embodiments below. The accompanying drawings are only used for the purpose of illustrating the optional embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0024] Figure 1 The application environment of the power battery pack pretreatment method according to an embodiment of the present application;

[0025] Figure 2 is a schematic flow chart of a power battery pack pretreatment method according to an embodiment of the present application;

[0026] Figure 3 It is a flowchart of the step of obtaining the target number of cycles in one embodiment of the present application;

[0027] Figure 4a This is a diagram of the main frequency data change of an embodiment of the present application;

[0028] Figure 4b This is a response speed variation diagram of an embodiment of the present application;

[0029] Figure 5 It is a flowchart of the step of determining the cycle number interval in one embodiment of the present application;

[0030] Figure 6 It is a flowchart of the step of determining the cycle number interval according to the expansion force data in one embodiment of the present application;

[0031] Figure 7a is an expansion force variation curve of an embodiment of the present application;

[0032] Figure 7b is an expansion force variation curve of an embodiment of the present application;

[0033] Figure 7c is an expansion force variation curve of an embodiment of the present application;

[0034] Figure 8 is a transmissibility curve of an embodiment of the present application;

[0035] Fig. 9 1 is a flow chart of a step of determining a target number of cycles according to an embodiment of the present application;

[0036] Fig.10 is a schematic diagram of the pretreatment effect of an embodiment of the present application;

[0037] Fig.11 is a structural block diagram of a power battery pack pretreatment device according to an embodiment of the present application;

[0038] Fig.12is a structural block diagram of a power battery pack pretreatment device according to an embodiment of the present application;

[0039] Fig.13 It is a diagram of the internal structure of a computer device according to an embodiment of the present application. DETAILED DESCRIPTION

[0040] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0042] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0043] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0044] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0045] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0046] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0047] With the development of new energy technology and automobile technology, electric vehicles using power batteries are becoming more and more popular. In the design and manufacturing process of power batteries for electric vehicles, structural durability and strength testing is a very important test. At present, before conducting structural durability and strength tests, the power battery pack is usually pre-treated with current circulation to eliminate the mechanical stress and strain caused by the power battery pack during the assembly process. However, there are cases where the current circulation pre-treatment is insufficient and the test sample does not match the actual product status. For example, the test sample has not undergone sufficient current circulation treatment, the expansion is insufficient, the structure is relatively loose, the amplitude is larger in the structural durability and strength test, and it is more prone to failure, resulting in poor results in structural durability and strength testing.

[0048] An embodiment of the present application provides a power battery pack pretreatment scheme, in which experiments such as current cycle treatment and main frequency measurement are performed on a sample power battery pack in advance, and a target number of cycles is determined based on the experimental data. In this way, when structural durability and strength tests are required, it is only necessary to pretreatment the test samples according to the target number of cycles to make the test samples consistent with the actual product status, thereby improving the effects of the structural durability and strength tests.

[0049] The power battery pack pretreatment method provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown. The application environment includes a computer device 101, a cycle processing device 102 and a main frequency measurement device 103, and the computer device 102 can communicate with the cycle processing device 102 and the main frequency measurement device 103 through a network. The data storage system can store the data that the computer device 101 needs to process. The data storage system can be integrated on the computer device 101, or it can be placed on the cloud or other network servers. The above-mentioned computer device 101 can be, but not limited to, various personal computers, laptops, smart phones, tablet computers, etc. The above-mentioned cycle processing device 102 can be, but not limited to, various charging and discharging motors, capacity machines, capacity distribution cabinets, etc. The above-mentioned main frequency measurement device 102 can be, but not limited to, an automotive modal device.

[0050] According to some embodiments of the present application, referring to Figure 2, provides a power battery pack pretreatment method, which is applied as follows Figure 1 Taking the computer device in the example as an example, the following steps may be included:

[0051] Step 201, obtaining the target number of cycles.

[0052] The target number of cycles is determined by current cycling and main frequency measurement of the sample power battery pack. The current cycling includes charging and discharging the sample power battery pack, and one charge and discharge is one cycle. The main frequency is the natural frequency of the power battery pack.

[0053] Before pre-processing the target power battery pack, a series of experiments are conducted using the sample power battery pack to collect relevant data. The experimental process may include: using a cyclic processing device to cyclically process the sample power battery pack, and after each cyclic processing, using a main frequency measurement device to measure the main frequency of the sample power battery pack to obtain experimental data.

[0054] The computer device obtains the experimental data from the main frequency measurement device, and then uses a preset algorithm to analyze the experimental data, and determines the target number of cycles based on the analysis results.

[0055] In practical applications, a large number of experiments can be conducted to obtain a large amount of experimental data. The computer device determines the target number of cycles based on the large amount of experimental data and stores the target number of cycles in a preset database. Later, when it is necessary to pre-process the test samples used for structural durability and strength tests, the computer device can query the target number of cycles from the preset database.

[0056] It should be noted that the method for obtaining the target cycle number is not limited to the above description, and in practical applications, other methods can also be used to obtain it.

[0057] Step 202: pre-process the target power battery pack according to the target cycle number.

[0058] Among them, the target power battery pack is the test sample used for structural durability and strength testing.

[0059] After obtaining the target number of cycles, the computer device can transmit the target number of cycles to the cycle processing device, so that the cycle processing device can charge and discharge the target power battery pack according to the target number of cycles. Alternatively, the computer device can also generate a control signal according to the target number of cycles, and send the control signal to the cycle processing device; the cycle processing device pre-processes the target power battery pack according to the control signal. The computer device can also display the target number of cycles so that the tester can control the cycle processing device to pre-process the target power battery pack according to the target number of cycles. It should be noted that the pre-processing method is not limited to the above description. In practical applications, other pre-processing methods can also be used.

[0060] In the above embodiment, the target number of cycles is obtained; and the target power battery pack is pre-processed according to the target number of cycles. In the technical solution of the embodiment of the present application, when structural durability and strength tests are required, the test samples are pre-processed according to the target number of cycles, so that the test samples are consistent with the actual product status, thereby improving the effect of structural durability and strength tests.

[0061] According to some embodiments of the present application, referring to Figure 3 , the process of obtaining the target number of cycles may include the following steps:

[0062] Step 301 : in a process of performing current cycle processing on a first sample power battery pack, a plurality of main frequency data obtained by measuring the main frequency of the first sample power battery pack is obtained every preset number of cycles.

[0063] In the process of collecting the main frequency data, a first sample power battery pack is used, wherein the first sample power battery pack has not been subjected to charging and discharging treatment before the experiment. The experimental process may include: using a circulation treatment device to perform current circulation treatment on the first sample power battery pack; after each current circulation treatment, using a main frequency measurement device to perform main frequency measurement on the first sample power battery pack to obtain main frequency data; and a computer device obtains the main frequency data of the first sample power battery pack from the main frequency measurement device.

[0064] In practical applications, it takes a lot of time to measure the main frequency after each current cycle. Therefore, in order to save experimental time and improve experimental efficiency, the main frequency measurement device can be used to measure the main frequency of the first sample power battery pack for a preset number of cycles. For example, the main frequency measurement device is used to measure the main frequency of the first sample power battery pack every 5 current cycles. In this way, after 20 current cycles, 4 main frequency data can be collected.

[0065] Step 302, determining the target number of cycles according to the changing trend of the main frequency data.

[0066] The computer device can determine the changing trend of the main frequency data based on the main frequency data, and then determine the target number of cycles based on the changing trend of the main frequency data.

[0067] For example, the main frequency of the first sample power battery pack that has not been subjected to current circulation treatment is measured to obtain the main frequency f0; then, the first sample power battery pack is subjected to current circulation treatment 5 times, and the main frequency of the first sample power battery pack is measured to obtain the main frequency f1; and so on, the main frequencies f2, f3, etc. can be obtained. The computer device determines that the frequency change from the main frequency f0 to the main frequency f1 is greater than the preset frequency threshold; however, the frequency change from the main frequency f1 to the main frequencies f2 and f3 is less than the preset frequency threshold. Based on this change trend, the current circulation treatment corresponding to f1 for 5 times is determined as the target number of cycles.

[0068] Understandably, a low number of cycles may lead to insufficient pretreatment of the power battery pack, while a high number of cycles may lead to a long pretreatment time and low pretreatment efficiency. The changing trend of the main frequency data can reflect the turning point between a low number of cycles and a high number of cycles. Therefore, a more reasonable number of cycles can be determined based on this turning point.

[0069] In the above embodiment, during the current cycle processing of the first sample power battery pack, multiple main frequency data obtained by measuring the main frequency of the first sample power battery pack are obtained for each preset number of cycles; the target number of cycles is determined according to the change trend of the main frequency data. In the technical solution of the embodiment of the present application, a more reasonable target number of cycles can be determined according to the change trend of the main frequency data with the number of cycles, that is, the target number of cycles can not only make the test sample undergo more sufficient pretreatment, but also save pretreatment time and improve pretreatment efficiency.

[0070] According to some embodiments of the present application, the process of obtaining multiple main frequency data obtained by measuring the main frequency of the first sample power battery pack per a preset number of cycles may include: obtaining the main frequency data obtained by measuring the main frequency of the first sample power battery pack by the automobile modal device per a preset number of cycles.

[0071] Normally, when using a main frequency measurement device to measure the main frequency of a power battery pack, it is necessary to assemble the power battery pack onto a fixture, and then install the fixture and the power battery pack together onto the main frequency measurement device. However, this measurement method introduces the influence of fixture assembly, and what is measured is the main frequency data of the power battery pack under the constraint of the fixture. Taking this situation into consideration, an embodiment of the present application uses an automotive modal device to measure the main frequency of a first sample power battery pack to obtain main frequency data. The computer device obtains multiple main frequency data of the first sample power battery pack from the automotive modal device.

[0072] For example, the main frequency of the first sample power battery pack that has not been subjected to current circulation treatment is measured using an automotive modal device to obtain a main frequency f0; then, the first sample power battery pack is subjected to current circulation treatment 5 times, and the main frequency of the first sample power battery pack is measured using an automotive modal device to obtain a main frequency f1; and so on, the main frequencies f2, f3, etc. can be obtained.

[0073] In the above embodiment, the main frequency data obtained by measuring the main frequency of the first sample power battery pack by the automobile modal device is obtained every preset number of cycles. In the technical solution of the embodiment of the present application, the power battery pack can be directly placed on the elastic suspension of the automobile modal device, without the need to use a fixture to fix the power battery pack. Therefore, the influence introduced by the fixture assembly can be eliminated, and the subtle main frequency differences can be accurately identified, thereby obtaining more accurate main frequency data.

[0074] According to some embodiments of the present application, the above-mentioned acquisition of main frequency data obtained by the automobile modal device through main frequency measurement of the first sample power battery pack may include: acquiring main frequency data obtained by the automobile modal device through main frequency measurement of the first sample power battery pack in a preset charge state.

[0075] The state of charge (SOC) is the ratio of the remaining capacity of a battery after it has been used for a period of time or has been left unused for a long time to its capacity in a fully charged state.

[0076] In the process of measuring the main frequency of the first sample power battery pack, the main frequency measurement can be performed on the first sample power battery pack at different charge states. For example, the main frequency of the first sample power battery pack with an SOC of 0% is measured using an automobile mode device, or the main frequency of the first sample power battery pack with an SOC of 100% is measured using an automobile mode device.

[0077] Figure 4a The figure shows the main frequency data changing with the number of cycles when the power battery pack has two charge states: SOC 0% and SOC 100%. It should be noted that in practical applications, the main frequency of the power battery pack under other charge states can also be measured.

[0078] In one of the embodiments, during the main frequency measurement, a vibration sweep frequency method may be used to collect response acceleration before and after the power battery pack is pre-processed. Figure 4b The variation of response acceleration with main frequency before and after preprocessing is shown.

[0079] In the above embodiment, the main frequency data obtained by measuring the main frequency of the first sample power battery pack under a preset charge state by the automobile modal device is obtained. In the technical solution of the embodiment of the present application, the main frequency data of the first sample power battery pack under different charge states can be obtained, and the target cycle number is determined according to the main frequency data under multiple charge states, which can improve the accuracy of the target cycle number.

[0080] According to some embodiments of the present application, referring to Figure 5 Before measuring the main frequency of the first sample power battery pack, the embodiment of the present application may also determine the cycle number interval first, so as to subsequently measure the main frequency of the first sample power battery pack within the cycle number interval. The process of determining the cycle number interval may include the following steps:

[0081] Step 401 : acquiring expansion force data of the second sample power battery pack during current circulation processing of the second sample power battery pack.

[0082] Among them, the second sample power battery pack was not charged and discharged before the experiment.

[0083] The experimental process may include: using a cycle processing device to perform current cycle processing on the second sample power battery pack, and after each cycle processing, collecting expansion force data of the second sample power battery pack through an expansion force measuring device; or, after each preset number of cycles, collecting expansion force data of the second sample power battery pack through the expansion force measuring device. The computer device obtains the expansion force data of the second sample power battery pack from the expansion force measuring device.

[0084] The expansion force measuring device mentioned above can be a sensor or a dedicated measuring device.

[0085] Step 402, determining the cycle number interval according to the amount of change of the expansion force data with the cycle number.

[0086] As the number of current cycles increases, the power battery pack continues to expand and generates a large expansion force. The computer device can determine the expansion force data in the target state based on the expansion force data in the initial state and the preset expansion force increase, and determine the cycle number interval based on the cycle number corresponding to the expansion force data in the target state.

[0087] For example, the expansion force data in the initial state is a0, and the increase in expansion force is Δa, then the expansion force data in the target state is determined to be a1=a0+Δa, wherein the number of cycles corresponding to a1 is m, and the cycle number interval is determined to be [0, m].

[0088] The expansion force increase can be determined according to a preset ratio, for example, if the preset ratio is 20%, then Δa=a0*20%. It should be noted that the expansion force data and the expansion force increase under the target state are not limited to the above description, and other methods can also be used.

[0089] Based on the above embodiment, the main frequency measurement may include: within the cycle number interval, obtaining a plurality of main frequency data obtained by measuring the main frequency of the first sample power battery pack every preset number of cycles.

[0090] For example, if the cycle number interval is [0, 20], the main frequency of the first sample power battery pack can be measured by the automotive modal device every 4 cycles or every 5 cycles to obtain the main frequency data. If the cycle number interval is [0, 30], the main frequency of the first sample power battery pack can be measured by the automotive modal device every 5 cycles or every 6 cycles to obtain the main frequency data.

[0091] The computer device may obtain the main frequency data from the automobile modal device after the automobile modal device collects the main frequency data each time; or the computer device may obtain the main frequency data from the automobile modal device after the automobile modal device collects multiple main frequency data.

[0092] In the above embodiment, during the current cycle processing of the second sample power battery pack, the expansion force data of the second sample power battery pack is obtained; and the cycle number interval is determined according to the change amount of the expansion force data with the cycle number. In the technical scheme of the embodiment of the present application, a more reasonable cycle number interval can be determined according to the expansion force, so as to determine a more reasonable main frequency measurement frequency within the cycle number interval, so that not only the main frequency data can be collected, but also the measurement efficiency of the main frequency data can be improved, thereby improving the efficiency of determining the target cycle number.

[0093] According to some embodiments of the present application, referring to Figure 6 The process of determining the cycle number interval according to the expansion force data may include the following steps:

[0094] Step 4021, drawing an expansion force variation curve according to the expansion force data.

[0095] Step 4022, when the expansion force variation curve is an upward convex curve, determine the cycle number interval according to the inflection point of the upward convex curve.

[0096] According to the expansion force data, we can draw Figure 7a , Figure 7b and Figure 7c The curve shown. Figure 7aTaking the convex curve shown in the figure as an example, before the inflection point, the expansion force data increases more with the increase of the number of cycles; and after the inflection point, the expansion force data increases less with the increase of the number of cycles. Therefore, the cycle number interval can be determined according to the inflection point of the convex curve.

[0097] Figure 7b The expansion force data in has no inflection point. Figure 7c The expansion force data first decreases and then increases. The expansion force data of the target state can be determined according to the amount of expansion force increase in the above embodiment, and then the cycle number interval can be determined according to the expansion force data of the target state.

[0098] In the above embodiment, an expansion force variation curve is drawn according to the expansion force data; when the expansion force variation curve is an upward convex curve, the cycle number interval is determined according to the inflection point of the upward convex curve. In the technical solution of the embodiment of the present application, the cycle number interval can be determined relatively easily and quickly according to the expansion force variation curve, thereby improving the efficiency of determining the target cycle number.

[0099] In practical applications, vibration isolation theory can be introduced to test the pretreatment effect. Figure 8 , the vertical axis is the transfer rate, the transfer rate is the ratio of the response acceleration of the measured part to the loading acceleration, and the horizontal axis is the ratio of the excitation frequency to the natural frequency. In the embodiment of the present application, the excitation frequency mainly refers to the excitation generated by the road surface during driving after the power battery is installed. As can be seen from the figure, when the transfer rate is equal to 1, the ratio of the excitation frequency to the natural frequency is 1.414; when the frequency ratio is greater than 1.414, the transfer rate is less than 1, as shown in the marked points in the figure. In other words, only when the excitation frequency is greater than 41.4% of the natural frequency can it play a role in avoiding resonance or isolating vibration. In many cases, a frequency interval of more than 40% is difficult to achieve. Therefore, when the natural frequency is 3Hz away from the excitation frequency, and the frequency interval between the natural frequency and the excitation distance accounts for 15% to 20% of the excitation frequency, the natural frequency of automotive parts is considered to be relatively reliable.

[0100] According to some embodiments of the present application, the candidate cycle number can be determined first, and the pre-processing effect of the candidate cycle number can be tested using the above-mentioned vibration isolation theory, and then the target cycle number can be determined based on the test result. Fig. 9 , involving the process of determining the target number of cycles according to the change trend of the main frequency data, may include the following steps:

[0101] Step 501, determining candidate cycle times according to the change trend of the main frequency data.

[0102] Referring to the above embodiment, during the current cycle processing of the first sample power battery pack, the automobile modal device measures the main frequency of the first sample power battery pack for each preset number of cycles to obtain a plurality of main frequency data; the computer device obtains the plurality of main frequency data from the automobile modal device. Then, the computer device may draw a main frequency variation curve based on the plurality of main frequency data, and determine the inflection point of the main frequency variation curve as the candidate cycle number.

[0103] Step 502, obtaining target main frequency data of the third sample power battery pack after being processed through the candidate cycle number cycle.

[0104] Among them, the third sample power battery pack was not charged and discharged before the experiment.

[0105] After determining the candidate number of cycles, the cycle processing device is used to perform current cycle processing on the third sample power battery pack. After processing the candidate number of cycles, the automotive modal device is used to measure the main frequency of the third sample power battery pack to obtain the main frequency data of the third sample power battery pack. The computer device obtains the main frequency data of the third sample power battery pack from the automotive modal device.

[0106] Step 503: If the main frequency data of the third sample power battery pack meets the preset conditions, the candidate cycle number is determined as the target cycle number.

[0107] The preset conditions include that the frequency interval between the fixed frequency and the excitation frequency is greater than or equal to 3 Hz, or that the frequency interval between the fixed frequency and the excitation frequency accounts for 15% to 20% of the excitation frequency.

[0108] After determining the main frequency data of the third sample power battery pack, the computer equipment determines the frequency interval between the natural frequency and the excitation frequency of the third sample power battery pack according to the main frequency data. If the frequency interval is greater than or equal to 3 Hz, or the frequency interval accounts for 15% to 20% of the excitation frequency, indicating that the natural frequency of the third sample power battery pack is relatively reliable, it is determined that the main frequency data of the third sample power battery pack meets the preset conditions, and the candidate cycle number is determined as the target cycle number.

[0109] If the frequency interval is less than 3Hz, or the frequency interval accounts for less than 15% to 20% of the excitation frequency, it is determined that the main frequency data of the third sample power battery pack does not meet the preset conditions. In this case, the candidate cycle number can be adjusted, and the new sample power battery pack can be tested according to the above steps until the main frequency data of the new sample power battery pack meets the preset conditions.

[0110] Reference Fig.10Before the power battery pack is pre-processed, the natural frequency of the power battery pack is close to the excitation frequency. After the power battery pack is fully pre-processed, the natural frequency of the power battery pack increases, which is farther away from the excitation frequency than before, and the response acceleration also decreases.

[0111] In the above embodiment, the candidate cycle number is determined according to the change trend of the main frequency data; the target main frequency data of the third sample power battery pack after the candidate cycle number is processed is obtained; if the main frequency data of the third sample power battery pack meets the preset conditions, the candidate cycle number is determined as the target cycle number. In the technical solution of the embodiment of the present application, the candidate cycle number is determined, and the candidate cycle number is tested using the vibration isolation theory, so that a more reasonable target cycle number can be determined, thereby performing a more adequate pretreatment of the test samples used in the structural durability and strength tests, and the pretreatment time can also be saved.

[0112] According to some embodiments of the present application, a power battery pack pretreatment method is provided, wherein the method is applied as follows: Figure 1 Taking the computer device in the example as an example, the following steps may be included:

[0113] Step 1: Acquire expansion force data of the second sample power battery pack during current circulation processing of the second sample power battery pack.

[0114] Step 2: Draw an expansion force variation curve based on the expansion force data.

[0115] Step 3: When the expansion force variation curve is an upward convex curve, determine the cycle number interval according to the inflection point of the upward convex curve.

[0116] Step 4: within the cycle number interval, obtain multiple main frequency data obtained by measuring the main frequency of the first sample power battery pack under a preset charge state by the automobile modal equipment every preset number of cycles.

[0117] Step 5: Determine the candidate cycle number according to the change trend of the main frequency data.

[0118] Step 6, obtaining the second main frequency data of the third sample power battery pack after the candidate cycle number cycle processing.

[0119] Step 7: If the main frequency data of the third sample power battery pack meets the preset conditions, the candidate cycle number is determined as the target cycle number.

[0120] Step 8: pre-treat the target power battery pack according to the target number of cycles.

[0121] In the above embodiment, the second sample chip is first used to perform an expansion force test experiment to obtain the trend of the expansion force data changing with the number of cycles; a more reasonable cycle number interval is determined based on the trend. The first sample data is then used to perform a main frequency test experiment to obtain the trend of the main frequency data, thereby determining a more reasonable target number of cycles based on the main frequency data. Using the target number of cycles to pre-treat the test samples used in the structural durability and strength tests can not only make the pre-treatment more sufficient, but also save pre-treatment time, improve pre-treatment efficiency, and thus improve the efficiency and accuracy of the structural durability and strength tests.

[0122] Based on the same inventive concept, the embodiment of the present application also provides a power battery pack pretreatment device for implementing the power battery pack pretreatment method involved above. The implementation solution provided by the device to solve the problem is similar to the implementation solution recorded in the above method, so the specific limitations in one or more power battery pack pretreatment device embodiments provided below can refer to the limitations of the power battery pack pretreatment method above, and will not be repeated here.

[0123] According to some embodiments of the present application, referring to Fig.11 , provides a power battery pack pretreatment device, the device comprising:

[0124] The number acquisition module 601 is used to obtain the target cycle number; the target cycle number is determined by performing current cycle processing and main frequency measurement on the sample power battery pack;

[0125] The pre-processing module 602 is used to pre-process the target power battery pack according to the target cycle number.

[0126] In some embodiments, the number acquisition module 601 is specifically used to obtain multiple main frequency data obtained by measuring the main frequency of the first sample power battery pack for a preset number of cycles during the current circulation process of the first sample power battery pack; and determine the target number of cycles according to the change trend of the main frequency data.

[0127] In some embodiments, the frequency acquisition module 601 is specifically used to obtain the main frequency data obtained by the automobile modal device through main frequency measurement of the first sample power battery pack for a preset number of times per cycle, wherein the automobile modal device adopts a vibration sweep frequency measurement method.

[0128] In some embodiments, the frequency acquisition module 601 is specifically used to obtain the main frequency data obtained by the automobile modal device measuring the main frequency of the first sample power battery pack under a preset charge state.

[0129] In some embodiments, reference Fig.12 , the device further comprises:

[0130] An expansion force acquisition module 603, used to acquire expansion force data of the second sample power battery pack during the current circulation process of the second sample power battery pack;

[0131] An interval determination module 604 is used to determine the cycle number interval according to the amount of change of the expansion force data with the cycle number;

[0132] Correspondingly, the number acquisition module 601 is specifically used to acquire a plurality of main frequency data obtained by measuring the main frequency of the first sample power battery pack every preset number of cycles within the cycle number interval.

[0133] In some embodiments, the interval determination module 604 is specifically used to draw an expansion force variation curve according to the expansion force data; when the expansion force variation curve is an upward convex curve, the cycle number interval is determined according to the inflection point of the upward convex curve.

[0134] In some embodiments, the number acquisition module 601 is specifically used to determine the candidate cycle number according to the change trend of the main frequency data; obtain the main frequency data of the third sample power battery pack after the candidate cycle number is cyclically processed; if the main frequency data of the third sample power battery pack meets the preset conditions, the candidate cycle number is determined as the target cycle number.

[0135] Each module in the above-mentioned power battery pack pre-processing device can be implemented in whole or in part by software, hardware and their combination. Each of the above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the corresponding operations of each of the above modules.

[0136] According to some embodiments of the present application, a power battery pack pretreatment system is provided. The power battery pack pretreatment system includes a circulation processing device, an automobile modal device and a computer device; the circulation processing device is used to perform current circulation processing on the power battery pack; the automobile modal device is used to measure the main frequency of the power battery pack to obtain the main frequency data; the computer device is used to determine the target number of cycles according to the main frequency data.

[0137] In the embodiment of the present application, the circulation processing device performs current circulation processing on the sample power battery pack. The computer device obtains the expansion force data of the power battery pack expansion force changing with the number of cycles, and draws the expansion force change curve according to the expansion force data. In the case where the expansion force change curve is an upward convex curve, the computer device determines the cycle number interval according to the inflection point of the upward convex curve. Within the cycle number interval, the automobile modal device performs main frequency measurement on the sample power battery pack under the preset state of charge for each preset number of cycles to obtain multiple main frequency data. The computer device obtains multiple main frequency data from the automobile modal device, and determines the candidate cycle number according to the change trend of the main frequency data. Afterwards, the circulation processing device is used to perform circulation processing on the sample power battery pack for the candidate cycle number, and the automobile modal device is used to measure the main frequency of the sample power battery pack after the circulation processing to obtain the main frequency data. The computer device determines whether the main frequency data of the sample power battery pack meets the preset conditions; if it meets the preset conditions, the candidate cycle number is determined as the target cycle number; if it does not meet the preset conditions, the cycle number is adjusted to perform current circulation processing and main frequency measurement on the new sample power battery pack, thereby determining the target cycle number. Finally, a cycle processing device is used to pre-process the target power battery pack for the target number of cycles.

[0138] In some examples, the power battery pack pretreatment system further includes an expansion force measuring device, which is used to measure expansion force data of the power battery pack.

[0139] In the above embodiments, a power battery pack pretreatment system is used to conduct relevant experiments, and the test samples used in the structural durability and strength tests are pretreated, which can not only make the pretreatment more sufficient, but also save pretreatment time and improve pretreatment efficiency, thereby improving the efficiency and accuracy of the structural durability and strength tests.

[0140] According to some embodiments of the present application, a computer device is provided. The internal structure diagram of the computer device can be as follows: Fig.13As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. Among them, the processor, the memory and the input / output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program, wherein the computer program can be used to implement the above-mentioned functions such as inputting data, performing calculations, and outputting results. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a power battery pack preprocessing method is implemented.

[0141] Those skilled in the art will understand that Fig.13 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0142] According to some embodiments of the present application, there is also provided a non-transitory computer-readable storage medium including instructions, such as a memory including instructions, and the instructions can be executed by a processor of a computer device to perform the above method. For example, the non-transitory computer-readable storage medium can be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

[0143] According to some embodiments of the present application, a computer program product is also provided, and when the computer program is executed by a processor, the above method can be implemented. The computer program product includes one or more computer instructions. When these computer instructions are loaded and executed on a computer, part or all of the above method can be implemented in whole or in part according to the process or function described in the embodiment of the present application.

[0144] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0145] The above-described embodiments only express several implementation methods of the present application, which is convenient for understanding the technical solutions of the present application in detail, but cannot be understood as limiting the scope of protection of the invention patent. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the protection scope of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided in the present application are all within the protection scope of the attached claims described in the present application. Therefore, the protection scope of the patent of this application shall be based on the contents of the attached claims, and the description and drawings can be used to explain the contents of the claims.

Claims

1. A power battery pack pretreatment method, characterized in that: The method comprises: Obtaining a target number of cycles; the target number of cycles is determined by performing current cycling processing and main frequency measurement on a sample power battery pack; According to the target number of cycles, the target power battery pack is pre-processed.

2. The method according to claim 1, characterized in that The obtaining of the target number of cycles comprises: In the process of performing current cycle processing on the first sample power battery pack, a plurality of main frequency data obtained by measuring the main frequency of the first sample power battery pack is obtained every preset number of cycles; The target number of cycles is determined according to the changing trend of the main frequency data.

3. The method according to claim 2, characterized in that The multiple main frequency data obtained by measuring the main frequency of the first sample power battery pack per a preset number of cycles include: The main frequency data obtained by measuring the main frequency of the first sample power battery pack by the automobile modal device is obtained every preset number of cycles.

4. The method according to claim 3, characterized in that: The obtaining of the main frequency data obtained by measuring the main frequency of the first sample power battery pack by the automobile modal device includes: The main frequency data obtained by measuring the main frequency of a first sample power battery pack under a preset state of charge by the automobile modal device is obtained.

5. The method according to any one of claims 2 to 4, characterized in that: The method further comprises: During the current circulation process of the second sample power battery pack, obtaining expansion force data of the second sample power battery pack; Determining the cycle number interval according to the amount of change of the expansion force data with the cycle number; Correspondingly, the plurality of main frequency data obtained by measuring the main frequency of the first sample power battery pack per the preset number of cycles include: Within the cycle number interval, a plurality of main frequency data obtained by measuring the main frequency of the first sample power battery pack is obtained every preset number of cycles.

6. The method according to claim 5, characterized in that Determining the cycle number interval according to the trend of the expansion force data changing with the cycle number includes: Draw an expansion force variation curve according to the expansion force data; In the case where the expansion force variation curve is an upward convex curve, the cycle number interval is determined according to the inflection point of the upward convex curve.

7. The method according to claim 2, characterized in that Determining the target number of cycles according to the change trend of the main frequency data includes: Determine the candidate cycle number according to the change trend of the main frequency data; Obtaining main frequency data of a third sample power battery pack after being processed by the candidate number of cycles; If the main frequency data of the third sample power battery pack meets the preset conditions, the target cycle number is determined by the candidate cycle number.

8. A power battery pack pretreatment device, characterized in that: The device comprises: A number acquisition module is used to obtain a target cycle number; the target cycle number is determined by performing current cycle processing and main frequency measurement on a sample power battery pack; The preprocessing module is used to preprocess the target power battery pack according to the target number of cycles.

9. A power battery pack pretreatment system, characterized in that: The power battery pack pretreatment system includes a circulation treatment device, an automobile modal device and a computer device; The circulation processing equipment is used to perform current circulation processing on the power battery pack; The automotive modal device is used to measure the main frequency of the power battery pack to obtain main frequency data; The computer device is used to determine the target number of cycles according to the main frequency data.

10. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

12. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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