Method, device and equipment for detecting OH area ratio of battery cell
By establishing the correspondence between the OH area ratio and the leakage current integral value, and measuring and calculating the leakage current integral value, the problem of high complexity in OH area ratio detection in the existing technology is solved, and a simple and reliable OH area ratio detection and screening of battery cells is realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CONTEMPORARY AMPEREX TECHNOLOGY CO LTD
- Filing Date
- 2024-11-04
- Publication Date
- 2026-05-08
AI Technical Summary
Existing methods for detecting OH area ratio mainly rely on photographic imaging technology, which is computationally complex and has low versatility, making it difficult to meet the detection requirements of lithium batteries.
By measuring the integral value of the leakage current of the battery cell, and using the pre-established correspondence between the OH area ratio and the integral value of the leakage current, the OH area ratio of the battery cell is determined.
This paper presents a simple and effective method for detecting the OH area ratio, which reduces the dependence on photographic imaging technology and improves the reliability of detection and the efficiency of batch screening.
Smart Images
Figure CN121995246A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery testing technology, and in particular to methods, apparatus and equipment for detecting the percentage of OH area in a battery cell. Background Technology
[0002] Due to their advantages such as high energy density, rechargeability, safety, and environmental friendliness, power batteries are widely used in new energy vehicles, consumer electronics, and energy storage systems. Power batteries include, for example, lithium batteries. In lithium battery design, the negative electrode needs to have an area margin in both length and width directions compared to the positive electrode. The Overhang (OH) area ratio is typically used as a parameter to characterize the portion of the negative electrode that extends beyond the positive electrode in both length and width directions. This OH area ratio parameter is then used to test and screen battery cells.
[0003] Currently, the detection of OH area ratio is mostly based on photographic imaging technology, such as using x-ray images to calculate the OH area ratio of the battery. The detection method is singular, has few options, low calculation versatility, is computationally complex, and has high requirements for equipment algorithms, making it difficult to meet the detection needs of lithium batteries.
[0004] Therefore, how to provide a simpler and more effective method for detecting the OH area ratio is an urgent problem to be solved. Summary of the Invention
[0005] The main objective of this application is to provide a method, apparatus, and equipment for detecting the OH area ratio of a battery cell, aiming to provide a simpler and more effective method for detecting the OH area ratio.
[0006] To achieve the above objectives, this application proposes a method for detecting the OH area ratio of a battery cell, the method comprising:
[0007] Obtain the pre-established target correspondence between the OH area ratio of the first cell and the leakage current integral value; wherein, the leakage current integral value is the integral value obtained by integrating the leakage current of the first cell over time.
[0008] The first leakage current data of the second cell under test is measured, and the integral of the leakage current with respect to time in the first leakage current data is calculated to obtain the first integral value; wherein, the second cell and the first cell have the same design parameters except for the OH area ratio;
[0009] Based on the correspondence between the first integral value and the target, the OH area ratio of the second cell is determined.
[0010] In one embodiment, the measurement of the first leakage current data of the second cell under test includes:
[0011] Adjust the remaining charge state of the second battery cell to the target state of charge; wherein the voltage change of the second battery cell at the target state of charge is greater than a first value;
[0012] At the target SOC, the first leakage current data of the second cell under test is measured.
[0013] In this embodiment, during the measurement of the first leakage current data of the second cell, the SOC of the second cell can be adjusted to the target SOC before measurement, so that the voltage change amplitude of the second cell is greater than the first value. This can have a similar amplifying effect on the leakage current measured later, making it easier to measure the leakage current data more accurately, which in turn helps to more accurately select cells with a certain OH area ratio.
[0014] In one embodiment, the measurement of the first leakage current data of the second cell under test includes:
[0015] The second battery cell is placed in an oven, and the temperature of the oven is adjusted to a preset temperature range; wherein, the leakage current of the second battery cell in the preset temperature range is greater than a second value, and the preset temperature range is determined based on the capacity of the second battery cell;
[0016] Under the preset temperature range, the first leakage current data of the second cell to be tested is measured.
[0017] In this embodiment, during the measurement of the first leakage current data of the second battery cell, the second battery cell can be placed in an oven and adjusted to a preset temperature range before measurement, so that the measured leakage current can be greater than the second value and considered to be within the monitorable range. The specific preset temperature range can be determined according to the capacity of the second battery cell. For example, if the capacity of the battery cell is relatively small, a higher preset temperature range can be set to amplify the leakage current, which is more effective for monitoring and more accurate measurement of leakage current data. This is beneficial for more accurate screening of battery cells with a certain OH area ratio in the future.
[0018] In one embodiment, the measurement of the first leakage current data of the second cell under test includes:
[0019] Measure the open-circuit voltage of the second battery cell;
[0020] The second cell is charged to the open-circuit voltage using a target constant current value; wherein the target constant current value is determined based on the capacity of the second cell.
[0021] While keeping the voltage of the second cell at the open-circuit voltage, the charging current change over time is collected as the first leakage current data.
[0022] This embodiment provides a specific implementation method for measuring the first leakage current data. Specifically, the open-circuit voltage of the second battery cell is first measured. Then, the second battery cell is charged to the open-circuit voltage using a target constant current. If the capacity of the second battery cell is small, a smaller constant current can be used to charge it; if the capacity is large, a larger constant current can be used. After charging to the open-circuit voltage, a charging current is used to charge the second battery cell again, ensuring its voltage remains at the open-circuit voltage. The change in this charging current over time is then collected as the first leakage current data of the second battery cell.
[0023] In one embodiment, the method further includes:
[0024] The range of changes in the OH area ratio in the target correspondence is divided into N first sub-intervals; where N is an integer greater than 1.
[0025] Based on the target correspondence, determine the N second sub-intervals corresponding to the leakage current integral values of the N first sub-intervals respectively;
[0026] Among the N first sub-intervals, at least one first target interval is determined as a filtering condition;
[0027] Among the N second sub-intervals, at least one second target interval is determined to correspond to each of the at least one first target interval;
[0028] Select the second battery cell whose first integral value falls within the at least one second target range as the target battery cell.
[0029] In this embodiment, when a large number of target cells need to be screened to meet a certain OH area ratio requirement, the following preparatory work can be done first: First, according to certain tolerance requirements, the variation range of OH area ratio in the target correspondence is divided into multiple first sub-intervals to facilitate the screening of cells within a certain sub-interval. Specifically, based on the target correspondence, multiple second sub-intervals of leakage current integral values corresponding to the multiple first sub-intervals are determined, and these second sub-intervals are used as the specification ranges for screening to facilitate subsequent screening. In the specific screening, at least one first target interval is determined as the screening condition in the multiple first sub-intervals, and then the second target intervals corresponding to these first target intervals in the multiple second sub-intervals are determined. The second cells whose calculated first integral values are in these second target intervals are then screened as target cells that meet a certain OH area ratio requirement. This method facilitates the screening of cells with a large number of OH area ratios.
[0030] In one embodiment, before obtaining the pre-established target correspondence between the OH area ratio of the first cell and the leakage current integral value, the method further includes:
[0031] M groups of first battery cells with different OH area ratios are prepared; wherein M is an integer greater than 1, and the design parameters of the M groups of first battery cells are the same except for the OH area ratio;
[0032] For each of the first cells in the M groups, the second leakage current data corresponding to the first cell is measured, and the integral of the leakage current with respect to time in the second leakage current data is calculated to obtain the second integral value;
[0033] The target correspondence is established based on the OH area ratio and the second integral value corresponding to the first cells of the M groups.
[0034] This embodiment provides a specific implementation method for establishing a target correspondence. First, M groups of first cells with different OH area ratios need to be prepared. The only difference between the different groups of first cells is the design parameter of the OH area ratio, which facilitates the comparison to reflect the relationship between the OH area ratio and the leakage current integral value. Then, for each cell in the M groups of first cells, its corresponding second leakage current data is measured, and the leakage current integral over time in the leakage current data is calculated. Based on the OH area ratio and the second integral value of the leakage current corresponding to all first cells, a target correspondence is established, which facilitates the subsequent detection of the OH area ratio of unknown cells using this correspondence.
[0035] Furthermore, to achieve the above objectives, this application also proposes a device for detecting the OH area ratio of a battery cell, the device comprising:
[0036] The acquisition module is used to acquire a pre-established target correspondence between the OH area ratio of the first cell and the leakage current integral value; wherein, the leakage current integral value is the integral value obtained by integrating the leakage current of the first cell over time;
[0037] The measurement module is used to measure the first leakage current data of the second cell under test, and calculate the integral of the leakage current with respect to time in the first leakage current data to obtain the first integral value; wherein, the second cell and the first cell have the same design parameters except for the OH area ratio;
[0038] The determining module is used to determine the OH area ratio of the second cell based on the correspondence between the first integral value and the target.
[0039] In addition, to achieve the above objectives, this application also proposes a detection device for the OH area ratio of a battery cell, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the detection method for the OH area ratio of a battery cell as described above.
[0040] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the cell OH area ratio detection method described above.
[0041] In addition, to achieve the above objectives, this application also provides a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the cell OH area ratio detection method described above.
[0042] One or more technical solutions proposed in this application have at least the following technical effects:
[0043] First, a pre-established target correspondence is obtained. This correspondence characterizes the relationship between the OH area ratio and the leakage current integral value of the first cell. Then, this correspondence can be used to test a second cell with the same design but an unknown OH area ratio. Specifically, the first leakage current data of the second cell is measured, and the integral of the leakage current over time is calculated. Based on this integral value and the target correspondence obtained above, the OH area ratio of the second cell can be determined. Compared to related technologies that rely on photographic imaging technology and complex calculations to detect the OH area ratio, the method provided in this application does not rely on photographic imaging technology. Its testing process is simple, and data processing is straightforward. Since both the OH area ratio and the leakage current integral value of the cell are related to the lithium consumption of the cell, a correspondence between them can be established in advance. By measuring the leakage current integral value and comparing it with the correspondence, quantitative analysis of the OH area ratio can be achieved, resulting in high reliability and facilitating the screening of cells with varying OH area ratios in batches. Attached Figure Description
[0044] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.
[0045] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without creative effort.
[0046] Figure 1 One of the flowcharts provided for the detection method of OH area ratio of the battery cell in this application;
[0047] Figure 2 The second flowchart illustrates the detection method for the OH area ratio of the battery cell in this application.
[0048] Figure 3 The third flowchart illustrates the detection method for the OH area ratio of the battery cell in this application.
[0049] Figure 4 The fourth flowchart illustrates the detection method for the OH area ratio of the battery cell in this application.
[0050] Figure 5 Fifth flowchart illustrating the detection method for the OH area ratio of the battery cell in this application;
[0051] Figure 6 The sixth flowchart illustrates the detection method for the OH area ratio of the battery cell in this application.
[0052] Figure 7 The seventh flowchart illustrates the detection method for the OH area ratio of the battery cell in this application.
[0053] Figure 8 This is a schematic diagram of cells with different OH area ratios in the cell OH area ratio detection method of this application;
[0054] Figure 9 This is a schematic diagram illustrating the relationship between the leakage current integral value and the number of days in the detection method for the OH area ratio of the battery cell in this application;
[0055] Figure 10 This is a schematic diagram illustrating the relationship between the OH area ratio and the leakage current integral value in the detection method for the OH area ratio of the battery cell in this application.
[0056] Figure 11 This is a schematic diagram of the constant voltage leakage current detection principle in the method for detecting the OH area ratio of the battery cell in this application;
[0057] Figure 12 This is a schematic diagram showing the relationship between different OH area ratios and leakage current integral values in the detection method of the OH area ratio of the battery cell in this application;
[0058] Figure 13 A schematic diagram of the structure of the detection device for the OH area ratio of the battery cell in this application;
[0059] Figure 14 A schematic diagram of the structure of the device for detecting the OH area ratio of the battery cell in this application.
[0060] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0061] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.
[0062] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.
[0063] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.
[0064] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0065] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.
[0066] For battery cells, OH refers to the portion of the negative electrode that extends beyond the positive electrode in both length and width. It is an important parameter in battery cell design and can be expressed as the OH area ratio, which characterizes the ratio of the OH area to the area of the negative electrode or the positive electrode.
[0067] In terms of measurement, because there is a diaphragm between the negative electrode and the positive electrode, the portion of the negative electrode that extends beyond the positive electrode cannot be directly measured.
[0068] In related technologies, x-ray images are typically used to calculate the OH area of a battery, and then the OH area percentage. However, this method has certain limitations: low computational versatility, computational complexity, and high requirements for equipment algorithms, making it difficult to meet the detection needs of lithium batteries. Currently, OH area detection and screening are mostly based on photographic imaging technology, resulting in a single detection method and limited selectivity.
[0069] Therefore, how to provide more simple and effective OH area screening methods is a technical problem that needs to be solved.
[0070] To address the aforementioned technical issues, this application provides a method for detecting the OH area ratio of a battery cell. This method utilizes constant voltage leakage current testing technology to distinguish cells with different OH area ratios. This is because high-precision constant voltage leakage current testing equipment offers high accuracy and sensitivity, enabling quantitative analysis and rapid screening of cells in different states. Furthermore, the OH exhibits different lithium intercalation states at different cell SOC (State of Charge) states, and different OH area ratios also affect their lithium intercalation states, thus influencing the overall state of the battery cell.
[0071] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, or mobile phone, or an electronic device capable of performing the above functions. The following description uses an electronic device as an example to illustrate this embodiment and the subsequent embodiments.
[0072] Based on the above, this application provides a method for detecting the OH area ratio of a battery cell, referring to... Figure 1 , Figure 1 This is one of the flowcharts provided for the detection method of the OH area ratio of the battery cell in this application.
[0073] In this embodiment, the method for detecting the percentage of OH area in the battery cell includes steps S101 to S103:
[0074] Step S101: Obtain the pre-established target correspondence between the OH area ratio of the first cell and the leakage current integral value;
[0075] The leakage current integral value is obtained by integrating the leakage current of the first cell over time.
[0076] It should be noted that the first cell can be understood as a reference cell. A target correspondence is established in advance using this cell, so that the OH area ratio can be detected in subsequent cells to be tested based on this target correspondence.
[0077] It should also be noted that regarding leakage current, the voltage gradually decreases during battery storage, and the resulting capacity loss can be described as leakage current.
[0078] Step S102: Measure the first leakage current data of the second cell to be tested, and calculate the integral of the leakage current with respect to time in the first leakage current data to obtain the first integral value;
[0079] The second battery cell has the same design parameters as the first battery cell, except for the OH area ratio.
[0080] It should be noted that for the second cell to be tested, where the OH area ratio is unknown, it is necessary to first measure the first leakage current data of the cell. The first leakage current data may include the leakage current of the cell changing over time, where time can be seconds, minutes, hours, or days, etc., and this application does not impose any restrictions on this.
[0081] It should also be noted that the first integral value obtained by calculating the integral of the leakage current with respect to time in the first leakage current data can be used to characterize the lithium consumption caused by the leakage current for lithium batteries, that is, the amount of electricity gradually consumed by the lithium battery during use.
[0082] In some embodiments, the first and second cells may be, for example, laminated cells, hard-shell cells, etc.
[0083] Step S103: Determine the OH area ratio of the second cell based on the correspondence between the first integral value and the target.
[0084] It should be noted that for the second cell to be tested, whose OH area ratio is unknown, it is necessary to select the target correspondence of the first cell with the same design parameters except for the OH area ratio as a reference to determine the subsequent OH area ratio. Specifically, the OH area ratio of the second cell is determined based on the calculated first integral value and the target correspondence.
[0085] In some embodiments, the first integral value can be compared with the target correspondence, and the OH area ratio corresponding to the first integral value can be selected from the target correspondence as the OH area ratio of the second cell.
[0086] In other embodiments, the leakage current integral value interval where the first integral value is located can be determined in the target correspondence, and the interval of OH area ratio corresponding to the leakage current integral value interval can be selected in the target correspondence. Then, the average value and other data of the interval of OH area ratio can be determined as the OH area ratio of the second cell; or the determined OH area ratio interval can be directly output as the OH area ratio of the second cell. This application does not limit this.
[0087] Specifically, this application first obtains a pre-established target correspondence, which is used to characterize the relationship between the OH area ratio of the first cell and the leakage current integral value. Then, the correspondence can be used to detect the second cell with the same design but unknown OH area ratio. Specifically, the first leakage current data of the second cell is measured first, and the integral of the leakage current with respect to time in the data is calculated. Then, based on the integral value and the target correspondence obtained above, the OH area ratio of the second cell can be determined.
[0088] The method for detecting the OH area ratio of a battery cell provided in this application embodiment differs from related technologies that rely on photographic imaging technology and require complex calculations to detect the OH area ratio. The method provided in this application does not rely on photographic imaging technology, has a simple testing process, and simplifies data processing. Since both the OH area ratio and the leakage current integral value of the battery cell are related to the lithium consumption of the battery cell, a correspondence between the two can be established in advance. By measuring the leakage current integral value and comparing it with the correspondence, a quantitative analysis of the OH area ratio can be achieved. This method has high reliability and facilitates the screening of battery cells with high OH area ratio in batches.
[0089] The following describes how to measure the first leakage current data of the second battery cell, using feasible implementation methods:
[0090] In one feasible implementation, refer to Figure 2 , Figure 2 The second flowchart provided for the method of detecting the OH area ratio of the battery cell in this application includes the following steps S201 to S202:
[0091] Step S201: Adjust the SOC of the second battery cell to the target SOC;
[0092] The voltage change of the second cell under the target SOC is greater than the first value.
[0093] It's important to note that SOC refers to the percentage of usable charge within a battery relative to its nominal capacity. It's a crucial monitoring metric for the battery management system (BMS), which uses the SOC value to control the battery's operating state. In essence, the SOC reflects the battery's state of charge, and this applies to each individual cell within the battery.
[0094] It should also be noted that the first value mentioned above can be set according to the actual situation. The goal is to adjust the SOC of the second cell so that its voltage change range is larger, thereby making the leakage current of the second cell larger and playing a similar role in amplifying the leakage current so that it is within the monitorable range. This application does not limit the setting of the first value.
[0095] Step S202: Under the target SOC, measure the first leakage current data of the second cell to be tested.
[0096] In some embodiments, adjusting the SOC of the second battery cell to the target SOC can be achieved by fully charging the second battery cell using a charging and discharging device and then discharging it to the target SOC. The charging and discharging device can be, for example, a high-precision charge and discharge machine (UHPC).
[0097] In other embodiments, the first value of the target SOC can be determined experimentally. For example, for laminated cells, the target SOC can be set to 21% SOC, 60% SOC, etc., when the cell voltage is at a ramp (considered to have a large change range). This application does not limit this.
[0098] In this embodiment of the application, during the measurement of the first leakage current data of the second cell, the SOC of the second cell can be adjusted to the target SOC before measurement, so that the voltage change amplitude of the second cell is greater than the first value. This can have a similar amplifying effect on the leakage current measured later, making it easier to measure the leakage current data more accurately, and thus helping to more accurately screen out cells with a certain OH area ratio.
[0099] In another feasible implementation, refer to Figure 3 , Figure 3 The third flowchart provided for the detection method of OH area ratio of the battery cell in this application includes the following steps S301 to S302:
[0100] Step S301: Place the second battery cell in the oven and adjust the temperature of the oven to a preset temperature range;
[0101] Wherein, the leakage current of the second cell in the preset temperature range is greater than the second value, and the preset temperature range is determined according to the capacity of the second cell.
[0102] It should be noted that the second value can be set according to the actual situation, so that the leakage current of the second cell can also be relatively large, which can play a similar role in amplifying the leakage current and keep it within the monitorable range. This application does not limit the setting of the second value.
[0103] It should also be noted that the preset temperature range can be determined based on the capacity of the second cell. If the cell is a stacked cell with a relatively small capacity, a higher preset temperature range can be set, such as around 60°C, to amplify the leakage current of the cell, making it easier to monitor effectively and measure the leakage current data more accurately. This will help to more accurately select cells with a certain OH area ratio in the future. If the cell is a hard-shell cell with a relatively large capacity, there is no need to set a higher preset temperature range. For example, it is sufficient to keep the oven at around 20-30°C.
[0104] Step S302: Under the preset temperature range, measure the first leakage current data of the second cell to be tested.
[0105] In this embodiment of the application, during the measurement of the first leakage current data of the second battery cell, the second battery cell can be placed in an oven and adjusted to a preset temperature range before measurement, so that the measured leakage current can be greater than the second value and is considered to be within the monitorable range. The specific preset temperature range can be determined according to the capacity of the second battery cell. For example, if the capacity of the battery cell is relatively small, a higher preset temperature range can be set to amplify the leakage current, which is convenient for effective monitoring and more accurate measurement of leakage current data. This is beneficial for subsequent more accurate screening of battery cells with a certain OH area ratio.
[0106] In another feasible implementation, refer to Figure 4 , Figure 4 The fourth flowchart of the method for detecting the OH area ratio of the battery cell in this application includes the following steps S401 to S403:
[0107] Step S401: Measure the open-circuit voltage of the second cell.
[0108] It should be noted that the second battery cell can be connected to the UHPC to charge and discharge the second battery cell and measure its open-circuit voltage.
[0109] In some embodiments, the second cell can be charged and discharged using a UHPC, fully charged and then discharged to 21% SOC, and the open-circuit voltage of the second cell at this point is measured and used for subsequent leakage current measurement.
[0110] In other embodiments, the second cell can be charged and discharged using a UHPC. After being fully charged, it is discharged to 21% SOC. The temperature of the oven containing the second cell is adjusted to 60°C. After the temperature stabilizes, the open-circuit voltage of the second cell is recorded for subsequent leakage current measurement.
[0111] Step S402: Charge the second cell to the open-circuit voltage using the target constant current value;
[0112] The target constant current value is determined based on the capacity of the second battery cell.
[0113] It should be noted that the target constant current value for charging the second battery cell can be determined specifically based on the capacity of the second battery cell.
[0114] 1) If the capacity of the second cell is small, a smaller constant current can be used to charge the cell. For example, for a cell with a relatively small capacity, such as a laminated cell, 0.5mA can be set as the target constant current value.
[0115] 2) If the capacity of the second cell is large, a larger constant current can be used to charge the cell. For example, for a cell with a relatively large capacity, such as a hard-shell cell, the target constant current value can be appropriately increased from 0.5mA.
[0116] Step S403: While keeping the voltage of the second cell at the open-circuit voltage, collect data on the change of charging current over time, and use this data as the first leakage current data.
[0117] It should be noted that due to the self-discharge of the second cell, leakage current will be generated, causing the voltage of the second cell to be unable to be maintained at the open circuit voltage and the voltage will continue to drop. At this time, the second cell is charged by the charging current to maintain it at the open circuit voltage. The charging current collected at this time can be considered to be equal to the leakage current of the second cell's self-discharge. Collecting the data of the change of this charging current over time can also be considered as collecting the data of the change of leakage current over time, that is, the first leakage current data.
[0118] This application provides a specific implementation method for measuring the first leakage current data. Specifically, the open-circuit voltage of the second battery cell is first measured. Then, the second battery cell is charged to the open-circuit voltage using a target constant current. If the capacity of the second battery cell is small, a smaller constant current can be used to charge it; if the capacity of the second battery cell is large, a larger constant current can be used. After charging to the open-circuit voltage, a charging current is used to charge the second battery cell again, so that the voltage of the second battery cell can be maintained at the open-circuit voltage. At this time, the data of the change of the charging current over time is collected as the first leakage current data of the second battery cell.
[0119] The following describes how to select target battery cells that meet certain screening criteria, using feasible implementation methods:
[0120] In one feasible implementation, refer to Figure 5 , Figure 5 The fifth flowchart provides a method for detecting the OH area ratio of the battery cell in this application. The method includes the following steps S501 to S505:
[0121] Step S501: Divide the range of changes in the OH area ratio in the target correspondence into N first sub-intervals;
[0122] Where N is an integer greater than 1.
[0123] It should be noted that the size of N can be set according to the actual situation, and the sizes of the N first sub-intervals can be set to be the same or different. The specific settings can be made according to the actual situation, and this application does not impose any restrictions on this.
[0124] Step S502: Based on the target correspondence, determine the N second sub-intervals corresponding to the leakage current integral values of the N first sub-intervals respectively.
[0125] Step S503: Among the N first sub-intervals, at least one first target interval is determined as a filtering condition.
[0126] Step S504: Among the N second sub-intervals, determine at least one second target interval corresponding to each of the at least one first target interval.
[0127] Step S505: Select the second battery cell whose first integral value falls within the at least one second target range as the target battery cell.
[0128] For example, the OH area ratio of the battery cell can be designed to be within a certain tolerance range, such as a design requirement of 6.3% ± 1.0%. In this case, 6.3% ± 1.0% can be set as a first sub-interval. According to the target correspondence, the first sub-interval can be determined to correspond to the second sub-interval of 1.77-1.80mAh. Then, 1.77-1.80mAh can be used as a screening specification. If it is necessary to screen out battery cells with an OH area ratio that meets 6.3% ± 1.0%, the second battery cell to be tested can be screened using the screening specification of 1.77-1.80mAh. The second battery cell with a first integral value within 1.77-1.80mAh is selected as the target battery cell.
[0129] In this embodiment of the application, when it is necessary to screen a large number of target cells that meet a certain OH area ratio requirement, the following preparatory work can be done first: First, according to certain tolerance requirements, the variation range of OH area ratio in the target correspondence is divided into multiple first sub-intervals to facilitate the screening of cells within a certain sub-interval. Specifically, according to the target correspondence, multiple second sub-intervals of leakage current integral values corresponding to the multiple first sub-intervals are determined, and these second sub-intervals are used as the specification ranges for screening to facilitate subsequent screening. In the specific screening, at least one first target interval is determined as the screening condition in the multiple first sub-intervals, and then the second target intervals corresponding to these first target intervals in the multiple second sub-intervals are determined. The second cells whose calculated first integral values are in these second target intervals are then screened as target cells that meet a certain OH area ratio requirement. This method facilitates the screening of cells with a large number of OH area ratios.
[0130] The following section explains how to establish the target correspondence, using feasible implementation methods as an example:
[0131] In one feasible implementation, refer to Figure 6 , Figure 6The sixth flowchart of the method for detecting the OH area ratio of the battery cell in this application includes the following steps S601 to S603:
[0132] Step S601: Prepare the first cells of group M with different OH area ratios;
[0133] Where M is an integer greater than 1, and the design parameters of the first cells in the M groups are the same except for the OH area ratio.
[0134] It should be noted that the size of M can be set according to the actual situation, and the number of first cells in the first cells of M groups can also be set according to the actual situation. For example, each group of first cells can be set to include 3 cells. This application does not limit this.
[0135] In some embodiments, three groups of first cells can be respectively configured with OH area percentages of 0% (no OH), 6.3% (normal area OH), and 12.6% (OH area doubled). For stacked cells, the OH area percentage can be controlled by simply changing the anode electrode size and the corresponding separator size, while the cathode size can remain constant. The separator size can be changed with the anode electrode size.
[0136] Step S602: For each first cell in the M group of first cells, measure the second leakage current data corresponding to the first cell, and calculate the integral of the leakage current with respect to time in the second leakage current data to obtain the second integral value.
[0137] Step S603: Establish the target correspondence relationship based on the OH area ratio and the second integral value corresponding to the first cells of the M groups.
[0138] It should be noted that the larger M is, and / or the more cells in the first cell of each group, the more accurate the established target correspondence will be. The established target correspondence can, for example, change linearly. For example, the expression of the established target correspondence is y = 0.0014x + 0.0017; where x represents the OH area ratio and y represents the leakage current integral value.
[0139] This application provides a specific implementation method for establishing a target correspondence. First, M groups of first cells with different OH area ratios are prepared. The only difference between the different groups of first cells is the design parameter of the OH area ratio, which facilitates comparison reflecting the relationship between the OH area ratio and the leakage current integral value. Then, for each cell in the M groups of first cells, its corresponding second leakage current data is measured, and the integral of the leakage current with respect to time is calculated. Finally, based on the OH area ratio and the second integral value of the leakage current corresponding to all first cells, a target correspondence is established, facilitating the subsequent detection of the OH area ratio of unknown cells using this correspondence.
[0140] The following example illustrates the method for detecting the OH area ratio of the battery cell provided in the embodiments of this application.
[0141] Current screening and detection technologies for OH area proportions place high demands on the imaging capabilities of equipment and the processing algorithms, resulting in limited methodologies. Developing simpler and more effective detection methods would provide more technological options, reduce reliance on single devices, and allow for application in research and analysis across various scenarios.
[0142] The method for detecting the OH area ratio of the battery cell provided in this application mainly adopts the following technical concept:
[0143] Development of constant voltage leakage current testing method → Obtaining leakage current data of cells with different OH area ratios → Quantitatively analyzing the impact of different OH area ratios on leakage current and establishing the data relationship between OH area ratio and leakage current integral value → Defining leakage current specification value → Screening cells with different OH area ratios.
[0144] Figure 7 The seventh flowchart illustrates the detection method for the OH area ratio of the battery cell in this application. Figure 7 As shown, the method for detecting the OH area ratio of the battery cell includes steps S701 to S705, specifically:
[0145] Step S701: Prepare battery cells with different OH area ratios.
[0146] For example, stacked cells with different OH area ratios are first prepared. The OH area ratio of different groups of cells is controlled only by changing the size of the anode electrode and the corresponding diaphragm size. That is, stacked cells with different OH area ratios are prepared by controlling the OH area ratio by only changing the size of the anode electrode and the corresponding diaphragm size, while keeping the cathode size unchanged. Figure 8 This is a schematic diagram of cells with different OH area ratios in the detection method of the OH area ratio of the battery cell in this application, as shown below. Figure 8 As shown, the following three groups of laminated cells are included. The slanted areas in the figure represent the OH regions:
[0147] 1) Group A - No OH, OH area percentage is 0%.
[0148] 2) Group B - The area ratio of conventional OH and OH is 6.3%.
[0149] 3) In group C, the area of -OH doubled, and the proportion of OH area was 12.6%.
[0150] Step S702: Obtain leakage current data through constant current and constant voltage testing.
[0151] For example, different groups of cells can be adjusted to different SOCs for testing. Finally, three cells from each group of cells with different OH area ratios are taken, fully charged, and then discharged to 21% SOC.
[0152] Next, record the open-circuit voltage and use a UHPC to perform constant current and constant voltage leakage current tests to obtain leakage current data for different groups of cells. Specifically, connect the regulated cells to the UHPC, adjust the oven temperature to 60℃, and record the open-circuit voltage of the cells after the temperature stabilizes. Then set the constant current and constant voltage process: charge the cells with a constant current of 0.5mA to the corresponding open-circuit voltage and maintain the constant voltage, record the constant voltage current change data as leakage current data.
[0153] Step S703: Establish the relationship curve between the integral value of leakage current and the proportion of OH area.
[0154] For example, after obtaining leakage current data of cells with different OH area ratios, the corresponding leakage current integral value is calculated, and a relationship curve between different OH area ratios and leakage current integral values is established.
[0155] Figure 9 This diagram illustrates the relationship between the integral value of leakage current and the number of days in the detection method for the OH area ratio of the battery cell in this application. Figure 9 As shown, after collecting leakage current data corresponding to cells with OH area ratios of 0%, 6.3%, and 12.6%, the leakage current can be integrated to obtain the integrated leakage current value, and a correspondence between the integrated leakage current value and the number of days can be established.
[0156] Figure 10 This diagram illustrates the relationship between the OH area ratio and the integral value of leakage current in the cell OH area ratio detection method of this application. Figure 10 As shown, after establishing the correspondence between the leakage current integral value and the number of days, the leakage current integral value of, for example, the 5th or 6th day can be selected to establish the correspondence between the leakage current integral value and the OH area ratio of different cells. This correspondence can then be used as the target correspondence to assist in detecting the OH area ratio of other cells.
[0157] It should also be noted that the detection principle of leakage current is... Figure 11 This is a schematic diagram illustrating the constant voltage leakage current detection principle in the cell OH area ratio detection method of this application, as shown below. Figure 11 As shown, when one of the positive and negative electrodes is on a platform and the other is on a slope, the voltage drop of the entire battery is the same as the voltage drop on the slope side. At this time, the current I_cc added to maintain a constant potential should be equal to the self-discharge current (i.e., leakage current I_leak) on that electrode to amplify the voltage drop signal. The figure shows the self-discharge current I_sc of the negative electrode as an example of I_leak. Specifically, the self-discharge analyzer is used to add water to maintain a constant water level and measure the amount of water added. Here, the amount of water added is used to characterize the leakage current as an example.
[0158] Step S704: Develop screening specifications based on the curve between different OH area ratios and leakage current integral values.
[0159] Specifically, Figure 12 This is a schematic diagram illustrating the relationship between different OH area proportions and leakage current integral values in the cell OH area proportion detection method of this application, as shown below. Figure 12 As shown, the integral value of leakage current for cells with different OH area ratios conforms to a linear equation, with the form y = 0.0014x + 0.0017. However, the OH area ratio requirement for cell design must meet certain tolerance requirements, such as a design OH area ratio of 6.3% ± 1.0%. Based on this tolerance requirement, the leakage current screening specification value for cells with a 6.3% OH area can be defined as 1.77-1.80mAh. Figure 12 The dimensions of the area enclosed by the rectangle.
[0160] Step S705: Select cells with different OH area ratios based on specification values.
[0161] Specifically, based on the leakage current screening specifications established above, accurate screening of cells with different OH area ratios can be achieved, and the screened cells can be guaranteed to have good consistency.
[0162] In this embodiment, by analyzing the OH area ratio and leakage current integral value, a relationship equation between the OH area and the leakage current integral value can be obtained (representing the above-mentioned target correspondence). This equation allows for quantitative analysis of the OH area ratio of different cells, thereby defining leakage current screening specifications based on OH size requirements. Cells with different OH area ratios are then screened using the leakage current integral value. Compared to conventional x-ray detection technology, this detection method has a simple testing process, does not rely on complex algorithms, has simple data processing, and high feasibility. Through conventional constant voltage leakage current testing, cells with different OH area ratios can be distinguished based on the leakage current integral value. Establishing the correspondence between the OH area ratio and the leakage current integral value allows for the formulation of OH specification values to achieve batch screening of cells with high reliability, effectively achieving the goal of screening cells with different OH area ratios in batches.
[0163] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the detection method of the OH area ratio of the battery cell in this application. Any simple modifications based on this technical concept are within the protection scope of this application.
[0164] This application also provides a device for detecting the OH area ratio of a battery cell, please refer to... Figure 13 , Figure 13 A schematic diagram of the structure of the cell OH area ratio detection device provided in this application. The cell OH area ratio detection device includes:
[0165] The acquisition module 1301 is used to acquire a pre-established target correspondence between the OH area ratio of the first cell and the leakage current integral value; wherein, the leakage current integral value is the integral value obtained by integrating the leakage current of the first cell over time.
[0166] The measurement module 1302 is used to measure the first leakage current data of the second cell under test, and calculate the integral of the leakage current with respect to time in the first leakage current data to obtain the first integral value; wherein, the second cell and the first cell have the same design parameters except for the OH area ratio;
[0167] The determining module 1303 is used to determine the OH area ratio of the second cell based on the correspondence between the first integral value and the target.
[0168] The battery cell OH area ratio detection device provided in this application adopts the battery cell OH area ratio detection method in the above embodiments. Its testing process is simple, data processing is simple, and reliability is high, which facilitates the purpose of batch screening of battery cells with OH area ratio.
[0169] Compared with related technologies, the beneficial effects of the battery cell OH area ratio detection device provided in this application are the same as those of the battery cell OH area ratio detection method provided in the above embodiments, and other technical features in the battery cell OH area ratio detection device are the same as those disclosed in the above embodiments, and will not be repeated here.
[0170] This application provides a device for detecting the OH area ratio of a battery cell. The device includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the battery cell OH area ratio detection method in any of the above embodiments.
[0171] The following is for reference. Figure 14 , Figure 14 This is a schematic diagram of the structure of a cell OH area ratio detection device provided in this application, illustrating a structure suitable for implementing the cell OH area ratio detection device in the embodiments of this application. The cell OH area ratio detection device in the embodiments of this application may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Description), PMPs (Portable Media Players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 14 The device shown for detecting the OH area ratio of the battery cell is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.
[0172] like Figure 14As shown, the cell OH area ratio detection device may include a processing unit 1401 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1402 or a program loaded from a storage device 1403 into a random access memory (RAM) 1404. The RAM 1404 also stores various programs and data required for the operation of the cell OH area ratio detection device. The processing unit 1401, ROM 1402, and RAM 1404 are interconnected via a bus 1405. An input / output (I / O) interface 1406 is also connected to the bus. Typically, the following systems can be connected to I / O interface 1406: input devices 1407 including, for example, touchscreens, touchpads, keyboards, mice, image sensors, microphones, accelerometers, gyroscopes, etc.; output devices 1408 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 1403 including, for example, magnetic tapes, hard disks, etc.; and communication devices 1409. Communication device 1409 allows the cell OH area ratio detection device to exchange data wirelessly or via wired communication with other devices. Although cell OH area ratio detection devices with various systems are shown in the figure, it should be understood that it is not required to implement or possess all of the systems shown. More or fewer systems may be implemented alternatively.
[0173] Specifically, according to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1403, or installed from ROM 1402. When the computer program is executed by processing device 1401, it performs the functions defined in the methods of the embodiments disclosed in this application.
[0174] The battery cell OH area ratio detection device provided in this application, employing the battery cell OH area ratio detection method described in the above embodiments, solves the technical problem of how to provide a simpler and more effective OH area ratio detection method. Compared with related technologies, the beneficial effects of the battery cell OH area ratio detection device provided in this application are the same as those of the battery cell OH area ratio detection method provided in the above embodiments, and other technical features in this battery cell OH area ratio detection device are the same as those disclosed in the previous embodiment method, and will not be repeated here.
[0175] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.
[0176] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
[0177] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, the computer-readable program instructions being used to execute the cell OH area ratio detection method in the above embodiments.
[0178] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.
[0179] The aforementioned computer-readable storage medium may be included in the detection device for the OH area ratio of the battery cell; or it may exist independently and not be assembled into the detection device for the OH area ratio of the battery cell.
[0180] The aforementioned computer-readable storage medium carries one or more programs. When these programs are executed by a cell OH area ratio detection device, the cell OH area ratio detection device performs the following steps: obtaining a pre-established target correspondence between the OH area ratio of a first cell and the leakage current integral value; wherein the leakage current integral value is the integral value obtained by integrating the leakage current of the first cell with respect to time; measuring the first leakage current data of the second cell to be tested, and calculating the integral of the leakage current with respect to time in the first leakage current data to obtain a first integral value; wherein the second cell has the same design parameters as the first cell except for the OH area ratio; and determining the OH area ratio of the second cell based on the first integral value and the target correspondence.
[0181] Computer program code for performing the operations of this application can be written in one or more programming languages or a combination thereof, including object-oriented programming languages such as Java, Smalltalk, and C++, and conventional procedural programming languages such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a Local Area Network (LAN) or a Wide Area Network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).
[0182] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.
[0183] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.
[0184] The readable storage medium provided in this application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., a computer program) for executing the above-described method for detecting the OH area ratio of battery cells. Its testing process is simple, data processing is straightforward, and reliability is high, facilitating the batch screening of battery cells based on OH area ratio. Compared with related technologies, the beneficial effects of the computer-readable storage medium provided in this application are the same as those of the battery cell OH area ratio detection method provided in the above embodiments, and will not be elaborated upon here.
[0185] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the above-described method for detecting the percentage of OH area in a battery cell.
[0186] The computer program product provided in this application has a simple testing process, easy data processing, and high reliability, making it convenient for screening cells with high OH area ratio in batches. Compared with related technologies, the beneficial effects of the computer program product provided in this application are the same as those of the cell OH area ratio detection method provided in the above embodiments, and will not be repeated here.
[0187] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.
Claims
1. A method for detecting the OH area ratio of a battery cell, characterized in that, The method includes: Obtain the pre-established target correspondence between the OH area ratio of the first cell and the leakage current integral value; wherein, the leakage current integral value is the integral value obtained by integrating the leakage current of the first cell over time. The first leakage current data of the second cell under test is measured, and the integral of the leakage current with respect to time in the first leakage current data is calculated to obtain the first integral value; wherein, the second cell and the first cell have the same design parameters except for the OH area ratio; Based on the correspondence between the first integral value and the target, the OH area ratio of the second cell is determined.
2. The method as described in claim 1, characterized in that, The first leakage current data of the second cell under test includes: Adjust the remaining charge state of the second battery cell to the target state of charge; wherein the voltage change of the second battery cell at the target state of charge is greater than a first value; At the target SOC, the first leakage current data of the second cell under test is measured.
3. The method as described in claim 1 or 2, characterized in that, The first leakage current data of the second cell under test includes: The second battery cell is placed in an oven, and the temperature of the oven is adjusted to a preset temperature range; wherein, the leakage current of the second battery cell in the preset temperature range is greater than a second value, and the preset temperature range is determined based on the capacity of the second battery cell; Under the preset temperature range, the first leakage current data of the second cell to be tested is measured.
4. The method as described in claim 1 or 2, characterized in that, The first leakage current data of the second cell under test includes: Measure the open-circuit voltage of the second battery cell; The second cell is charged to the open-circuit voltage using a target constant current value; wherein the target constant current value is determined based on the capacity of the second cell. While keeping the voltage of the second cell at the open-circuit voltage, the charging current change over time is collected as the first leakage current data.
5. The method as described in claim 1, characterized in that, The method further includes: The range of changes in the OH area ratio in the target correspondence is divided into N first sub-intervals; where N is an integer greater than 1. Based on the target correspondence, determine the N second sub-intervals corresponding to the leakage current integral values of the N first sub-intervals respectively; Among the N first sub-intervals, at least one first target interval is determined as a filtering condition; Among the N second sub-intervals, at least one second target interval is determined to correspond to each of the at least one first target interval; Select the second battery cell whose first integral value falls within the at least one second target range as the target battery cell.
6. The method as described in claim 1, characterized in that, Before obtaining the pre-established target correspondence between the OH area ratio of the first cell and the integral value of the leakage current, the method further includes: M groups of first battery cells with different OH area ratios are prepared; wherein M is an integer greater than 1, and the design parameters of the M groups of first battery cells are the same except for the OH area ratio; For each of the first cells in the M groups, the second leakage current data corresponding to the first cell is measured, and the integral of the leakage current with respect to time in the second leakage current data is calculated to obtain the second integral value; The target correspondence is established based on the OH area ratio and the second integral value corresponding to the first cells of the M groups.
7. A device for detecting the OH area ratio of a battery cell, characterized in that, The device includes: The acquisition module is used to acquire a pre-established target correspondence between the OH area ratio of the first cell and the leakage current integral value; wherein, the leakage current integral value is the integral value obtained by integrating the leakage current of the first cell over time; The measurement module is used to measure the first leakage current data of the second cell under test, and calculate the integral of the leakage current with respect to time in the first leakage current data to obtain the first integral value; wherein, the second cell and the first cell have the same design parameters except for the OH area ratio; The determining module is used to determine the OH area ratio of the second cell based on the correspondence between the first integral value and the target.
8. A device for detecting the OH area ratio of a battery cell, characterized in that, The device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the method for detecting the OH area ratio of the battery cell as described in any one of claims 1 to 6.
9. A storage medium, characterized in that, The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, it implements the steps of the method for detecting the OH area ratio of the battery cell as described in any one of claims 1 to 6.
10. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the steps of the method for detecting the OH area ratio of the battery cell as described in any one of claims 1 to 6.