A battery storage test method and device

Abstract

The present invention provides a battery storage test method and device. The battery storage test method includes: obtaining initial test parameters of a battery to be tested, where the initial test parameters include the current state of charge of the battery to be tested; testing the current open-circuit voltage of the battery to be tested under the current state of charge; extracting the standard state of charge corresponding to the current open-circuit voltage from the relationship curve between the state of charge and the open-circuit voltage corresponding to the battery to be tested; adjusting the state of charge of the battery to be tested based on the relationship between the current state of charge and the standard state of charge, and returning to the step of testing the current open-circuit voltage of the battery to be tested under the current state of charge until the current state of charge is consistent with the standard state of charge; testing the open-circuit voltage and internal resistance of the battery to be tested before putting it into the furnace; and performing a storage test on the battery to be tested after the open-circuit voltage and internal resistance test before putting it into the furnace pass. The battery storage test method can timely determine whether the current state of charge is consistent with the standard state of charge, ensuring the accuracy of the test parameters.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular, to a battery storage test method and device. Background Art

[0002] The storage life of a lithium-ion battery is an important research project for lithium-ion batteries. The storage life refers to the time required for the performance of the battery to decay to a certain amount when stored at a certain state of charge and temperature. During the storage process of the battery, a series of chemical and physical changes will occur to the internal materials as the storage time becomes longer, which is called aging. The main manifestation is the phenomenon of self-discharge, resulting in a decrease in the capacity and power performance of the battery, an increase in impedance, and the aging process has the characteristics of irreversibility and non-repeatability. In order to study the storage performance of the battery, it is usually necessary to adjust the battery to a specific SOC (state of charge) before putting it into the storage device for storage, and test and record parameters such as the SOC and voltage of the battery. In the prior art, after the SOC of the battery is adjusted, it is usually directly put into the storage device for storage. If the test parameters do not meet the requirements due to test process errors or other factors, the test method of the prior art cannot detect parameter errors in time before storage, which will lead to the unavailability of the storage data this time, not only delaying the test progress, but also affecting the subsequent storage performance trend of the battery, causing great difficulties in data analysis, and affecting the evaluation effect and project progress of the battery. Summary of the Invention

[0003] In view of this, embodiments of the present invention provide a battery storage test method and device to overcome the problem in the prior art that it is difficult to ensure the accuracy of test parameters before battery storage test, thereby delaying the test progress and affecting the storage performance trend of the battery.

[0004] According to a first aspect, an embodiment of the present invention provides a battery storage test method, including:

[0005] Obtain initial test parameters of the battery to be tested, where the initial test parameters include the current state of charge of the battery to be tested;

[0006] Test the current open-circuit voltage of the battery to be tested in the current state of charge;

[0007] Extract the standard state of charge corresponding to the current open-circuit voltage from the relationship curve between the state of charge and the open-circuit voltage of the battery to be tested;

[0008] Based on the relationship between the current state of charge and the standard state of charge, adjust the state of charge of the battery to be tested, and return to the step of testing the current open-circuit voltage of the battery to be tested in the current state of charge until the current state of charge is consistent with the standard state of charge;

[0009] Perform an open - circuit voltage and internal resistance test on the battery to be tested before putting it into the furnace;

[0010] After the open - circuit voltage and internal resistance test before putting it into the furnace pass, perform a storage test on the battery to be tested.

[0011] Optionally, the adjustment of the state of charge of the battery to be tested based on the relationship between the current state of charge and the standard state of charge includes:

[0012] When the current state of charge is greater than the standard state of charge, discharge the battery to be tested;

[0013] When the current state of charge is less than the standard state of charge, charge the battery to be tested.

[0014] Optionally, before adjusting the state of charge of the battery to be tested based on the relationship between the current state of charge and the standard state of charge, the method further includes:

[0015] Judge whether the difference between the current state of charge and the standard state of charge is less than a first preset threshold;

[0016] When the difference between the previous state of charge and the standard state of charge is less than the first preset threshold, determine that the current state of charge is consistent with the standard state of charge.

[0017] Optionally, the initial test parameters further include: the current charge / discharge rate and the current charge / discharge time. Before testing the current open - circuit voltage of the battery to be tested under the current state of charge, the method further includes:

[0018] Judge whether the relationship between the current charge / discharge rate and the current charge / discharge time meets the requirements of the current state of charge;

[0019] When the relationship between the current charge / discharge rate and the current charge / discharge time meets the requirements of the current state of charge, test the current open - circuit voltage of the battery to be tested under the current state of charge.

[0020] Optionally, the method further includes:

[0021] When the relationship between the current charge / discharge rate and the current charge / discharge time does not meet the requirements of the current state of charge, verify the initial test parameters;

[0022] After the verification passes, test the current open - circuit voltage of the battery to be tested under the current state of charge.

[0023] Optionally, after performing the open - circuit voltage and internal resistance test on the battery to be tested before putting it into the furnace, the method further includes:

[0024] Determine whether the open-circuit voltage and internal resistance test values before furnace charging are within a preset range;

[0025] When the open-circuit voltage and internal resistance test values before furnace charging are not within the preset range, readjust the initial test parameters of the battery under test;

[0026] When the open-circuit voltage and internal resistance test values before furnace charging are within the preset range, determine that the open-circuit voltage and internal resistance tests before furnace charging are passed.

[0027] Optionally, the determining whether the open-circuit voltage and internal resistance test values before furnace charging are within a preset range includes:

[0028] Obtain a sample mean control chart corresponding to the battery under test;

[0029] Determine whether the open-circuit voltage and internal resistance test values before furnace charging are within the control limits of the sample mean control chart.

[0030] According to a second aspect, an embodiment of the present invention provides a battery storage test device, including:

[0031] An acquisition module, configured to acquire initial test parameters of a battery under test, where the initial test parameters include the current state of charge of the battery under test;

[0032] A first processing module, configured to test the current open-circuit voltage of the battery under test in the current state of charge;

[0033] A second processing module, configured to extract a standard state of charge corresponding to the current open-circuit voltage from a relationship curve between the state of charge and the open-circuit voltage corresponding to the battery under test;

[0034] A third processing module, configured to adjust the state of charge of the battery under test based on the relationship between the current state of charge and the standard state of charge, and return to the step of testing the current open-circuit voltage of the battery under test in the current state of charge until the current state of charge is consistent with the standard state of charge;

[0035] A fourth processing module, configured to perform an open-circuit voltage and internal resistance test on the battery under test before furnace charging;

[0036] A fifth processing module, configured to perform a storage test on the battery under test after the open-circuit voltage and internal resistance tests before furnace charging are passed.

[0037] According to a third aspect, an embodiment of the present invention provides an electronic device, including:

[0038] A memory and a processor, which are communicatively connected to each other. Computer instructions are stored in the memory, and the processor executes the computer instructions to execute the battery storage test method described in the first aspect and any of its optional embodiments.

[0039] According to the fourth aspect, an embodiment of the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the battery storage test described in the first aspect or any of its optional embodiments.

[0040] The technical solution of the present invention has the following advantages:

[0041] The battery storage test method and device provided by the embodiment of the present invention obtain initial test parameters of a battery to be tested, where the initial test parameters include the current state of charge of the battery to be tested; test the current open-circuit voltage of the battery to be tested under the current state of charge; extract the standard state of charge corresponding to the current open-circuit voltage from the relationship curve between the state of charge and the open-circuit voltage of the battery to be tested; adjust the state of charge of the battery to be tested based on the relationship between the current state of charge and the standard state of charge, and return to the step of testing the current open-circuit voltage of the battery to be tested under the current state of charge until the current state of charge is consistent with the standard state of charge; test the open-circuit voltage and internal resistance of the battery to be tested before putting it into the furnace; after the open-circuit voltage and internal resistance test before putting it into the furnace are passed, perform a storage test on the battery to be tested. Thus, by comparing the current state of charge of the battery to be tested with the standard state of charge corresponding to the battery to be tested, the relationship between the current state of charge and the standard state of charge can be obtained, and it can be timely determined whether the current state of charge is consistent with the standard state of charge. Furthermore, according to the relationship between the current state of charge and the standard state of charge, the current state of charge of the battery to be tested is adjusted to be consistent with the standard state of charge, ensuring the accuracy of the current state of charge of the battery to be tested, thereby ensuring the accuracy of the test parameters before storage, avoiding inaccurate test parameters caused by the inability to timely detect parameter errors before storage, avoiding delaying the test progress and affecting the storage performance trend of the battery, and thus ensuring the evaluation effect of the battery and the project progress. Description of the Drawings

[0042] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0043] Figure 1Flow chart of the battery storage test method according to an embodiment of the present invention;

[0044] Figure 2 Schematic diagram of the battery storage test process according to an embodiment of the present invention;

[0045] Figure 3 Flow chart of the application steps of the control chart according to an embodiment of the present invention;

[0046] Figure 4 Schematic diagram of the SOC-OCV charge and discharge experimental curve according to an embodiment of the present invention;

[0047] Figure 5 Schematic diagram of the control chart according to an embodiment of the present invention;

[0048] Figure 6 Schematic diagram of the statistical process control method based on the process model according to an embodiment of the present invention;

[0049] Figure 7 Schematic diagram of the structure of a battery storage test device according to an embodiment of the present invention;

[0050] Figure 8 Schematic diagram of the structure of an electronic device according to an embodiment of the present invention. Detailed implementation manners

[0051] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0052] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and should not be construed as indicating or implying relative importance.

[0053] In the description of the present invention, it should be noted that, unless otherwise clearly defined and limited, the terms "installation", "connection" and "coupling" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and may also be the communication inside two components. It may be a wireless connection or a wired connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0054] The technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0055] The storage life of a lithium-ion battery is an important research item for lithium-ion batteries. The storage life refers to the time required for the performance of the battery to decay to a certain amount when stored at a certain state of charge and temperature. During the storage process of the battery, a series of chemical and physical changes will occur to its internal materials as the storage time becomes longer, which is called aging. The main manifestation is the phenomenon of self-discharge, resulting in a decrease in the capacity and power performance of the battery, an increase in impedance, and the aging process is irreversible and repetitive. In order to study the storage performance of the battery, it is usually necessary to adjust the battery to a specific SOC (state of charge) before putting it into a storage device for storage, and test and record parameters such as the SOC and voltage of the battery. In the prior art, after the SOC of the battery is adjusted, it is usually directly put into the storage device for storage. If the test parameters do not meet the requirements due to incorrect test procedures or other factors, the test method of the prior art cannot detect the parameter error in time before storage, which will result in the unavailability of the storage data this time, not only delaying the test progress, but also affecting the subsequent storage performance trend of the battery, causing great difficulties in data analysis, and affecting the evaluation effect and project progress of the battery.

[0056] Based on the above problems, an embodiment of the present invention provides a battery storage test method, as Figure 1 shown. The battery storage test method specifically includes the following steps:

[0057] Step S101: Obtain the initial test parameters of the battery to be tested.

[0058] Among them, the initial test parameters include the current state of charge of the battery under test. The initial test parameters of the battery under test are the target parameters required by the demand side to meet the state of the battery under test before being stored in the furnace. Usually, the battery needs to be taken out (i.e., out of the furnace) for performance testing during the entire storage process, and then put back into the storage device (i.e., into the furnace) to continue storage. Before the battery is stored in the furnace, the battery parameters need to be adjusted to the target parameters of storage. Among them, the adjustment of the state of charge (SOC) of the battery can be achieved by charging / discharging the battery through a test device. The information of the test steps for adjusting the SOC is recorded in the test program of the test device, and the current state of charge of the battery under test can be obtained from the test steps for adjusting the SOC.

[0059] Step S102: Test the current open-circuit voltage of the battery under test in the current state of charge.

[0060] Among them, the current open-circuit voltage corresponding to the current state of charge of the battery under test can be measured using the test module in the test device. The open-circuit voltage is the static voltage across the battery under test obtained after long-term open-circuit standing in the current state of charge. The above test process is recorded in the test module, and the important parameter information of the SOC adjustment step can be identified and extracted from the test steps of the test module using a macro program, so as to obtain the current open-circuit voltage of the battery under test.

[0061] Step S103: Extract the standard state of charge corresponding to the current open-circuit voltage from the relationship curve between the state of charge and the open-circuit voltage of the battery under test.

[0062] It should be noted that the same type of battery has a specific relationship curve between the state of charge and the open-circuit voltage (i.e., the SOC-OCV curve). In the standard SOC-OCV curve, each value of the state of charge (SOC) corresponds to a specific value of the open-circuit voltage (OCV). In the above step S103, the current open-circuit voltage of the battery under test obtained in step S102 is substituted into the standard SOC-OCV curve, so as to obtain the standard state of charge corresponding to the current open-circuit voltage of the battery under test on the standard SOC-OCV curve.

[0063] Among them, to obtain the SOC-OCV curve of the battery, usually after adjusting the SOC, it is necessary to first perform long-term open-circuit standing to eliminate the electrochemical polarization, concentration polarization, and ohmic polarization caused by the load current, and then measure the static voltage across the battery to obtain the OCV. However, the SOC needs to be adjusted multiple times and the test time of the entire test process is relatively long. If the battery is subjected to a small current charge and discharge test of 0.01C on a high-precision charge and discharge device under normal temperature conditions, the purpose of eliminating polarization can be achieved, and the test duration can be balanced. Finally, Figure 4The charging / discharging SOC-OCV curve shown. Since the temperature range of the battery is relatively wide when testing the open-circuit voltage OCV in actual operation, theoretically, SOC-OCV tests at different temperatures are required. However, it can be found that although the change in entropy is related to temperature, the actual test shows that the impact is not significant. Therefore, within a certain temperature range, the SOC at the temperature of the sample can be estimated by the OCV at room temperature, that is, the SOC-OCV curves measured at room temperature can be used for batteries at different temperatures. In addition, as can be seen from Figure 4 it can be seen that in the intermediate stage of the change in SOC, the change in OCV is small. In this plateau region, even a small measurement error of OCV may cause a large SOC deviation. To address the above problems, the measurement accuracy of the measurement system can be improved to reduce the systematic error and improve the measurement accuracy of the SOC-OCV curve in the plateau region. Among them, for ternary system batteries, the change rate of OCV with SOC is relatively obvious. Therefore, it is relatively easy to compare the current state of charge with the standard state of charge. However, the SOC-OCV curve of lithium iron phosphate system batteries has a relatively long plateau region, and the change of OCV with SOC in this region is very gentle. To prevent the OCV from deviating too much from the SOC curve and obtaining inaccurate corresponding information, it is necessary to strictly depolarize the standard SOC-OCV curve to avoid misjudgment. By establishing the above SOC-OCV curve, in addition to being used in step S103 of this embodiment, it can also be used in the following aspects: for battery cells with unknown SOC status, the SOC status of the current battery can be quickly judged by high-precision OCV detection. Especially when evaluating the consistency of single cells in a module and single cells with a long storage time, the relationship established between the two can be utilized. After inputting the open-circuit voltage into the macro program, the SOC value can be automatically generated; in addition, for battery safety tests, in most cases, the SOC status of the battery is required. There may be a situation where the battery is not tested in time according to the requirements of the test sheet after pretreatment, and the battery will be stored for a certain period of time, as well as other situations where the current SOC needs to be clarified before testing. Only by detecting the OCV and then comparing the relationship between OCV and SOC can the accurate SOC value be obtained.

[0064] Step S104: Based on the relationship between the current state of charge and the standard state of charge, adjust the state of charge of the battery to be tested, and return to the step of testing the current open-circuit voltage of the battery to be tested in the current state of charge until the current state of charge is consistent with the standard state of charge.

[0065] Among them, by comparing the current state of charge with the standard state of charge, the relationship between the two can be obtained. If the current state of charge is the same as the standard state of charge, there is no need to adjust the state of charge of the battery under test, and directly proceed to the next step. If the current state of charge is inconsistent with the standard state of charge, then adjust the current state of charge and return to the above step S102. Specifically, if the current state of charge is greater than the standard state of charge, then reduce the previous state of charge; if the current state of charge is less than the standard state of charge, then increase the previous state of charge; the consistency between the current state of charge and the standard state of charge means that the difference between the current state of charge and the standard state of charge is less than the first preset threshold, the current state of charge is close to the standard state of charge, and the difference between the two is within the error tolerance range. Optionally, the error is less than 3%. In practical applications, according to the different types of batteries, as long as the difference between the current state of charge and the standard state of charge is small and does not have a great impact on parameters such as battery voltage, the present invention is not limited thereto.

[0066] Step S105: Test the open-circuit voltage and internal resistance of the battery under test before putting it into the furnace.

[0067] Step S106: After the open-circuit voltage and internal resistance test before putting it into the furnace are passed, conduct a storage test on the battery under test.

[0068] It should be noted that the purpose of testing the open-circuit voltage and internal resistance of the battery under test before putting it into the furnace is to detect whether the battery under test meets the storage requirements, record the data for subsequent analysis of the battery performance. When the open-circuit voltage and internal resistance test before putting it into the furnace are passed, it indicates that the parameters of the battery under test meet the storage requirements, and the battery under test can be used for the storage test. At this time, the battery under test is placed in a storage device at a specific temperature with a specific state of charge and voltage for storage.

[0069] By performing the above steps, the battery storage test method provided by the embodiment of the present invention compares the current state of charge of the battery under test with the standard state of charge corresponding to the battery under test to obtain the relationship between the current state of charge and the standard state of charge, and can timely determine whether the current state of charge is the same as the standard state of charge. Furthermore, according to the relationship between the current state of charge and the standard state of charge, adjust the current state of charge of the battery under test to be the same as the standard state of charge, ensure the accuracy of the current state of charge of the battery under test, thereby ensuring the accuracy of the test parameters before storage, avoiding inaccurate test parameters caused by the inability to detect parameter errors in time before storage, avoiding delaying the test progress and affecting the storage performance trend of the battery, and thus ensuring the evaluation effect of the battery and the project progress.

[0070] Specifically, in one embodiment, the above step S104 specifically includes the following steps:

[0071] Step S201: When the current state of charge is greater than the standard state of charge, discharge the battery under test.

[0072] Step S202: When the current state of charge is less than the standard state of charge, charge the battery under test.

[0073] Among them, according to the magnitude of the difference between the current state of charge and the standard state of charge, the amount of charge / discharge of the battery under test can be calculated. Furthermore, according to the amount of charge / discharge required by the battery under test and the charge / discharge rate, the charge / discharge time can be calculated, thereby completing the adjustment of the state of charge of the battery under test.

[0074] Specifically, in one embodiment, before performing the above-mentioned step S104, the battery storage test method provided by the embodiment of the present invention further includes the following steps:

[0075] Step S107: Determine whether the difference between the current state of charge and the standard state of charge is less than a first preset threshold.

[0076] Step S108: When the difference between the previous state of charge and the standard state of charge is less than the first preset threshold, determine that the current state of charge is consistent with the standard state of charge.

[0077] It should be noted that the first preset threshold is a relatively small value. Optionally, the error between the previous state of charge and the standard state of charge calculated according to the first preset threshold is less than 3%. In practical applications, according to different types of batteries, as long as the difference between the current state of charge and the standard state of charge is small and does not cause a large impact on parameters such as battery voltage, the present invention is not limited thereto. By performing the above steps, the battery storage test method provided by the embodiment of the present invention can intuitively obtain whether the current state of charge is consistent with the standard state of charge by comparing the magnitude relationship between the difference between the current state of charge and the standard state of charge and the first preset threshold, which is convenient for subsequent judgment on whether to adjust the state of charge of the battery under test and is beneficial to improving work efficiency.

[0078] Specifically, in one embodiment, the initial test parameters further include: the current charge / discharge rate and the current charge / discharge time. Before performing the above-mentioned step S102, the battery storage test method provided by the embodiment of the present invention further includes the following steps:

[0079] Step S109: Determine whether the relationship between the current charge / discharge rate and the current charge / discharge time meets the requirements of the current state of charge.

[0080] Step S110: When the relationship between the current charge / discharge rate and the current charge / discharge time meets the requirement of the current state of charge, test the current open-circuit voltage of the battery under test at the current state of charge.

[0081] It should be noted that during the process of adjusting the state of charge, the state of charge of the battery is adjusted by charging and discharging the battery at a certain charge / discharge rate for a certain period of time. By performing an integral operation on the current charge / discharge rate and the current charge / discharge time, the charge / discharge amount can be calculated. Furthermore, based on the state of charge of the battery before charging / discharging, it can be determined whether the state of charge after charging / discharging corresponds to the target current state of charge required, thereby judging whether the relationship between the current charge / discharge rate and the current charge / discharge time meets the requirement of the current state of charge. If the current state of charge can be calculated based on the current charge / discharge rate and the current charge / discharge time, it indicates that there is no error in the test step, and the above-mentioned Step S102 can be executed, and then the comparison between the current state of charge and the standard state of charge can be carried out. Among them, the current charge / discharge rate and the current charge / discharge time can be identified and extracted from the SOC adjustment test step using a macro program.

[0082] Specifically, in one embodiment, the battery storage test method provided by the embodiments of the present invention further includes:

[0083] Step S111: When the relationship between the current charge / discharge rate and the current charge / discharge time does not meet the requirement of the current state of charge, verify the initial test parameters.

[0084] Step S112: After the verification is passed, test the current open-circuit voltage of the battery under test at the current state of charge.

[0085] It should be noted that the situation where the relationship between the current charge / discharge rate and the current charge / discharge time does not meet the requirement of the current state of charge means that the current state of charge cannot be calculated based on the current charge / discharge rate and the current charge / discharge time. In this case, it is necessary to verify the initial test parameters, including analyzing whether there are test errors in the test data, such as incorrect test step settings, etc., so as to promptly eliminate the incorrect data and avoid having a greater impact on the subsequent battery storage test.

[0086] Specifically, in one embodiment, after the above-mentioned Step S105, the battery storage test method provided by the embodiments of the present invention further includes:

[0087] Step S113: Judge whether the open-circuit voltage and internal resistance test values before entering the furnace are within a preset range.

[0088] Among them, because each battery inevitably has slight differences due to process and other reasons, the open circuit voltage and internal resistance test values ​​of each battery have slight differences. In addition, due to test accuracy and operation and other reasons, the test data of each battery will also have slight differences, but the differences are small, so the battery test data is allowed to have small fluctuations within a certain range. The preset range is a range set in advance to allow the open circuit voltage and internal resistance test values ​​to fluctuate. The open circuit voltage and internal resistance test values ​​fluctuating within the preset range are qualified battery data that meet the requirements.

[0089] Step S114: when the open circuit voltage and internal resistance test values ​​before entering the furnace are not within the preset range, the initial test parameters of the battery to be tested are readjusted.

[0090] Step S115: When the open circuit voltage and internal resistance test values ​​before entering the furnace are within a preset range, it is determined that the open circuit voltage and internal resistance test before entering the furnace have passed.

[0091] It should be noted that if the open circuit voltage and internal resistance test values ​​before entering the furnace are not within the preset range, that is, this set of test parameters is unqualified, the reason needs to be found out. If it is an error caused by data collection or calculation, it is necessary to eliminate the failed data, return to readjust the initial test parameters of the battery to be tested, and compare again until the open circuit voltage and internal resistance test values ​​before entering the furnace are within the preset range, so as to further ensure the accuracy of the test parameters.

[0092] Exemplarily, the above steps can be performed in a test monitoring system, which can monitor the quality of the test process in real time to prevent parameter errors from causing data unavailability; it can also inspect identified important parameters, monitor the test status, trace production information, collect and enter samples, and implement a series of tasks such as abnormal alarms, thereby improving the consistency level of test parameters.

[0093] Specifically, in one embodiment, the above step S113 specifically includes the following steps:

[0094] Step S301: Obtain a sample mean control chart corresponding to the battery to be tested.

[0095] It should be noted that batteries usually undergo offline inspection before testing to meet the corresponding standards. If the historical test data of battery samples is imported into the system in advance, the upper and lower limits of specifications can be formulated according to the input rules, and then the information code is scanned before the battery to be tested enters the furnace, and the voltage and internal resistance of the battery to be tested are tested. The system synchronizes the upload of the test data of the battery to be tested and the test data of the battery to be tested is automatically compared with the specification limits to check whether it is within the specification range, and automatically report errors. The open circuit voltage (OCV) and internal resistance test value (IMP) are both metrological data types. According to the data characteristics, a simple sample mean control chart can be preferred. Exemplarily, the upper and lower limits of the specifications are the control limits of the sample mean control chart, and the input rules are the rules for formulating the control limits of the sample mean control chart. Among them, the sample mean control chart is developed based on the historical data obtained from the offline inspection of sample batteries. The quality target of the sample data is 3σ level and 95% confidence interval. If the collected data does not satisfy the normal distribution, data transformation is required and analysis is performed based on the transformed data. At the same time, it is necessary to confirm the corresponding relationship y=F(x) between the data x before transformation and the data y after transformation.

[0096] Step S301: Determine whether the open circuit voltage and internal resistance test values ​​before entering the furnace are within the control limits of the sample mean control chart.

[0097] Combination Figure 5 As shown, the control limits of the sample mean control chart are: upper control limit UCL, center line CL and lower control limit LCL. The judgment of whether the open circuit voltage and internal resistance test value before entering the furnace are within the control limits of the sample mean control chart can be used to judge whether the control chart is in a stable state, that is, whether there is an out-of-bounds situation. If there is an out-of-bounds situation, the control chart is unstable. If the control chart is found to be unstable, the cause needs to be identified. If it is an error caused by data collection or calculation, the failed data needs to be eliminated. In addition, when it is determined that the process is in a controlled state and the process capability index meets the specified requirements, the control limits can be appropriately adjusted and narrowed to improve data accuracy. Combined with Figure 3 As shown, in daily testing activities, the process data of the test process can be called and entered at any time, and the historical data and process data can be combined to obtain a new sample mean control chart to determine whether the sample is abnormal and whether there is room for optimization. In addition, the updated sample data will form a large database for reference and use by R&D personnel of other projects.

[0098] Optionally, based on the understanding of control charts and the problem that a single control chart may have low detection power, other types of control charts can be introduced to assist in the analysis, or different control charts can be combined to continuously update and iterate, and then establish Figure 6The test process management system model with quality statistics and analysis as the main modules as shown

[0099] By performing the above steps, the battery storage test method provided by the embodiments of the present invention obtains the sample mean control chart corresponding to the battery to be tested, and then determines whether the open-circuit voltage and internal resistance test values before furnace charging are within the control limits of the sample mean control chart, so as to determine whether the open-circuit voltage and internal resistance test values before furnace charging are within the preset range, thereby being able to timely discover whether there are errors in the test parameters of the battery to be tested, further avoiding the problem of inaccurate test parameters, ensuring the reliability of the test parameters, and thus ensuring the smooth progress of the entire storage test and improving work efficiency.

[0100] It should be noted that the data processing software used in this embodiment is all general office software, which integrates various functions and macro programs developed for convenient data analysis. More professional analysis tools such as MINITAB or other software can also be used; this embodiment mainly provides a solution idea for optimizing the storage test, mainly examining whether the parameters meet the requirements and the consistency level. If there are other similar analysis methods, they can also be referred to and used. Similarly, it can also be extended to other tests or related fields.

[0101] The embodiments of the present invention also provide a battery storage test device, as Figure 7 shown. The battery storage test device includes:

[0102] An acquisition module 101, configured to acquire the initial test parameters of the battery to be tested, where the initial test parameters include the current state of charge of the battery to be tested. For detailed content, refer to the relevant description of step S101 in the above method embodiment, and details will not be repeated here.

[0103] A first processing module 102, configured to test the current open-circuit voltage of the battery to be tested in the current state of charge. For detailed content, refer to the relevant description of step S102 in the above method embodiment, and details will not be repeated here.

[0104] A second processing module 103, configured to extract the standard state of charge corresponding to the current open-circuit voltage from the relationship curve between the state of charge and the open-circuit voltage of the battery to be tested. For detailed content, refer to the relevant description of step S103 in the above method embodiment, and details will not be repeated here.

[0105] The third processing module 104 is configured to adjust the state of charge of the battery under test based on the relationship between the current state of charge and the standard state of charge, and return the step of testing the current open-circuit voltage of the battery under test in the current state of charge until the current state of charge is consistent with the standard state of charge. For detailed content, please refer to the relevant description of step S104 in the above method embodiment, which will not be elaborated here.

[0106] The fourth processing module 105 is configured to test the open-circuit voltage and internal resistance of the battery under test before it is put into the furnace. For detailed content, please refer to the relevant description of step S105 in the above method embodiment, which will not be elaborated here.

[0107] The fifth processing module 106 is configured to perform a storage test on the battery under test after the open-circuit voltage and internal resistance test before it is put into the furnace are passed. For detailed content, please refer to the relevant description of step S106 in the above method embodiment, which will not be elaborated here.

[0108] The battery storage test device provided by the embodiment of the present invention is used to execute the battery storage test method provided by the above embodiment. The implementation manner and principle are the same. For detailed content, please refer to the relevant description of the above method embodiment, which will not be elaborated here.

[0109] Through the collaborative cooperation of the above-mentioned various components, the battery storage test device provided by the embodiment of the present invention can obtain the relationship between the current state of charge and the standard state of charge by comparing the current state of charge of the battery under test with the standard state of charge corresponding to the battery under test, and can timely determine whether the current state of charge is consistent with the standard state of charge. Furthermore, according to the relationship between the current state of charge and the standard state of charge, the current state of charge of the battery under test is adjusted to be consistent with the standard state of charge, ensuring the accuracy of the current state of charge of the battery under test, thereby ensuring the accuracy of the test parameters before storage, avoiding inaccurate test parameters caused by the inability to timely detect parameter errors before storage, avoiding delaying the test progress and affecting the storage performance trend of the battery, and thus ensuring the evaluation effect of the battery and the project progress.

[0110] Figure 8 shows an electronic device according to an embodiment of the present invention, such as Figure 8 shown, the electronic device includes: a processor 901 and a memory 902. Among them, the processor 901 and the memory 902 can be connected through a bus or other means, Figure 8 Taking the connection through the bus as an example.

[0111] The processor 901 may be a Central Processing Unit (CPU). The processor 901 may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. chips, or combinations of the above types of chips.

[0112] As a non-transitory computer-readable storage medium, the memory 902 can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the methods in the above method embodiments. The processor 901 executes various functional applications and data processing of the processor by running the non-transitory software programs, instructions, and modules stored in the memory 902, that is, implements the methods in the above method embodiments.

[0113] The memory 902 may include a program storage area and a data storage area. Among them, the program storage area can store an operating system and application programs required for at least one function; the data storage area can store data created by the processor 901, etc. In addition, the memory 902 may include high-speed random access memory, and may also include non-transitory memory, such as at least one magnetic disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some embodiments, the memory 902 may optionally include a memory remotely set relative to the processor 901, and these remote memories can be connected to the processor 901 through a network. Examples of the above networks include, but are not limited to, the Internet, enterprise intranets, local area networks, mobile communication networks, and combinations thereof.

[0114] One or more modules are stored in the memory 902 and, when executed by the processor 901, execute the methods in the above method embodiments.

[0115] For the specific details of the above electronic device, reference can be made to the corresponding relevant descriptions and effects in the above method embodiments for understanding, and details are not described herein again.

[0116] Those skilled in the art can understand that to implement all or part of the processes in the above-described embodiment methods, it can be completed by instructing relevant hardware through a computer program. The implemented program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above various methods. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above types of memories.

[0117] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A battery storage test method, characterized in that, it includes: Obtain the initial test parameters of the battery under test, and the initial test parameters include the current state of charge of the battery under test; Test the current open-circuit voltage of the battery under test under the current state of charge; Extract the standard state of charge corresponding to the current open-circuit voltage from the relationship curve between the state of charge and the open-circuit voltage of the battery under test; Based on the relationship between the current state of charge and the standard state of charge, adjust the state of charge of the battery under test, and return to the step of testing the current open-circuit voltage of the battery under test under the current state of charge until the current state of charge is consistent with the standard state of charge; Test the open-circuit voltage and internal resistance of the battery under test before putting it into the furnace; After the open-circuit voltage and internal resistance test before putting it into the furnace pass, conduct a storage test on the battery under test; The adjustment of the state of charge of the battery under test based on the relationship between the current state of charge and the standard state of charge includes: when the current state of charge is greater than the standard state of charge, discharge the battery under test; When the current state of charge is less than the standard state of charge, charge the battery under test.

2. The method according to claim 1, characterized in that, Before adjusting the state of charge of the battery under test based on the relationship between the current state of charge and the standard state of charge, the method further includes: Judge whether the difference between the current state of charge and the standard state of charge is less than a first preset threshold; When the difference between the previous state of charge and the standard state of charge is less than the first preset threshold, determine that the current state of charge is consistent with the standard state of charge.

3. The method according to claim 2, characterized in that, The initial test parameters further include: the current charge / discharge rate and the current charge / discharge time. Before testing the current open-circuit voltage of the battery under test under the current state of charge, the method further includes: Judge whether the relationship between the current charge / discharge rate and the current charge / discharge time meets the requirements of the current state of charge; When the relationship between the current charge / discharge rate and the current charge / discharge time meets the requirements of the current state of charge, test the current open-circuit voltage of the battery under test under the current state of charge.

4. The method according to claim 3, characterized in that, The method further includes: When the relationship between the current charge / discharge rate and the current charge / discharge time does not meet the requirements of the current state of charge, verify the initial test parameters; After the verification passes, test the current open-circuit voltage of the battery under test under the current state of charge.

5. The method according to any one of claims 1-4, characterized in that, After testing the open-circuit voltage and internal resistance of the battery under test before putting it into the furnace, the method further includes: Judge whether the test values of the open-circuit voltage and internal resistance before putting it into the furnace are within a preset range; When the test values of the open-circuit voltage and internal resistance before putting it into the furnace are not within the preset range, readjust the initial test parameters of the battery under test; When the test values of the open-circuit voltage and internal resistance before putting it into the furnace are within the preset range, determine that the open-circuit voltage and internal resistance test before putting it into the furnace pass.

6. The method according to claim 5, wherein, the determination of whether the open-circuit voltage and internal resistance test values before entering the furnace are within a preset range includes: obtaining a sample mean control chart corresponding to the battery to be tested; determining whether the open-circuit voltage and internal resistance test values before entering the furnace are within the control limits of the sample mean control chart.

7. A battery storage test device, wherein, comprising: an acquisition module, configured to acquire initial test parameters of the battery to be tested, where the initial test parameters include the current state of charge of the battery to be tested; a first processing module, configured to test the current open-circuit voltage of the battery to be tested in the current state of charge; a second processing module, configured to extract the standard state of charge corresponding to the current open-circuit voltage from the relationship curve between the state of charge and the open-circuit voltage corresponding to the battery to be tested; a third processing module, configured to adjust the state of charge of the battery to be tested based on the relationship between the current state of charge and the standard state of charge, and return to the step of testing the current open-circuit voltage of the battery to be tested in the current state of charge until the current state of charge is consistent with the standard state of charge; the adjustment of the state of charge of the battery to be tested based on the relationship between the current state of charge and the standard state of charge includes: discharging the battery to be tested when the current state of charge is greater than the standard state of charge; charging the battery to be tested when the current state of charge is less than the standard state of charge; a fourth processing module, configured to perform an open-circuit voltage and internal resistance test on the battery to be tested before entering the furnace; a fifth processing module, configured to perform a storage test on the battery to be tested after the open-circuit voltage and internal resistance test before entering the furnace pass.

8. An electronic device, wherein, comprising: a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to execute the method according to any one of claims 1-6.

9. A computer-readable storage medium, wherein, the computer-readable storage medium stores computer instructions, and the computer instructions are used to cause the computer to execute the method according to any one of claims 1-6.

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