Abnormal battery screening method, device and equipment and readable storage medium

Abstract

This invention provides a method, apparatus, device, and readable storage medium for screening abnormal batteries, relating to the field of battery energy. The method includes: acquiring the voltage change of each battery to be determined from a pre-charge stage to an aging stage, identifying abnormal batteries whose voltage change exceeds a preset value; charging each battery to be screened at a first preset battery capacity state according to a preset charging strategy, and determining a first DC resistance; charging the batteries to be screened at a second preset battery capacity state according to the preset charging strategy, and determining a second DC resistance; and determining a relative resistance ratio based on the first and second DC resistances to screen out abnormal batteries that are not within a preset ratio range. This invention enables batch detection of battery anomalies, screening out healthy batteries for use from the source, greatly improving the user experience, and preventing abnormal batteries from reducing overall battery performance and shortening the battery life of the battery pack after use.

Description

Technical Field

[0001] This invention relates to the field of battery energy, and more particularly to a method, apparatus, device, and readable storage medium for screening abnormal batteries. Background Technology

[0002] Currently, battery malfunctions can usually only be detected during use by observing power issues such as insufficient power or shortened daily usage time. Prolonged battery malfunctions can have an irreversible impact on the overall performance of the battery, resulting in a significant reduction in battery life. Summary of the Invention

[0003] This invention provides a method, apparatus, device, and readable storage medium for screening abnormal batteries, which addresses the technical deficiency in the prior art of not screening abnormal batteries before they are put into use, and provides a technical solution for screening abnormal batteries by combining the root causes of battery abnormalities.

[0004] In a first aspect, the present invention provides a method for screening abnormal batteries, comprising:

[0005] Obtain the voltage change of each battery to be determined from the pre-charge stage to the aging stage, and determine the abnormal batteries whose voltage change is greater than a preset change based on the voltage change.

[0006] Each battery to be screened is charged according to a preset charging strategy under a first preset battery capacity state, and the first DC resistance corresponding to each battery to be screened is determined according to the first voltage change difference and the current change difference.

[0007] Each battery to be screened is charged according to the preset charging strategy under the second preset battery capacity state, and the second DC resistance corresponding to each battery to be screened is determined according to the second voltage change difference and the current change difference.

[0008] A relative resistance ratio is determined based on the first DC resistance and the second DC resistance corresponding to each battery to be screened, and abnormal batteries whose relative resistance ratio is not within a preset ratio range are screened based on the relative resistance ratio.

[0009] The batteries to be screened are determined based on the batteries whose voltage change is less than or equal to a preset change.

[0010] According to the abnormal battery screening method provided by the present invention, the step of obtaining the voltage change of each battery to be determined from the pre-charge stage to the aging stage, and determining abnormal batteries whose voltage change is greater than a preset change based on the voltage change, includes:

[0011] Obtain the first voltage of each battery to be determined after the pre-charge stage, and obtain the second voltage of each battery to be determined after the aging stage;

[0012] The voltage difference corresponding to each battery to be determined is determined based on the first voltage and the second voltage;

[0013] The voltage change for each battery to be determined is determined based on the voltage difference and the first voltage.

[0014] According to the abnormal battery screening method provided by the present invention, after determining abnormal batteries whose voltage change is greater than a preset change based on the voltage change amount, the method further includes:

[0015] All batteries whose voltage change is less than or equal to a preset change amount are identified as batteries to be sorted.

[0016] Obtain the nominal capacity of each battery to be sorted after the capacity grading stage, and identify the batteries whose nominal capacity is not within the preset nominal capacity range as abnormal batteries.

[0017] Batteries whose nominal capacity is within a preset nominal capacity range are identified as the batteries to be screened.

[0018] According to the abnormal battery screening method provided by the present invention, before obtaining the voltage change of each battery to be determined from the pre-charge stage to the aging stage, the method further includes:

[0019] For each original battery, pre-charge, aging and capacity testing are performed sequentially to obtain the first internal resistance value before the pre-charge stage, the second internal resistance value after the pre-charge stage, the third internal resistance value after the aging stage and the fourth internal resistance value after the capacity testing stage for each original battery.

[0020] The original battery with the first internal resistance value greater than the preset internal resistance value is identified as an abnormal battery; the original battery with the second internal resistance value greater than the preset internal resistance value is identified as an abnormal battery; the original battery with the third internal resistance value greater than the preset internal resistance value is identified as an abnormal battery; and the original battery with the fourth internal resistance value greater than the preset internal resistance value is identified as an abnormal battery.

[0021] The original battery whose first, second, third, and fourth internal resistance values ​​are all less than or equal to the preset internal resistance value is identified as the battery to be determined.

[0022] According to the abnormal battery screening method provided by the present invention, before charging each battery to be screened in a second preset battery capacity state according to the preset charging strategy, the method further includes:

[0023] The first preset battery capacity is determined based on the first preset percentage and the total battery capacity, and the second preset battery capacity is determined based on the second preset percentage and the total battery capacity.

[0024] Each battery to be screened is charged with a preset constant current until the battery capacity of each battery to be screened reaches the first preset battery capacity state.

[0025] After determining the first DC resistance corresponding to each battery to be screened, each battery to be screened is discharged based on a preset constant current until the battery capacity of each battery to be screened reaches the second preset battery capacity state.

[0026] The sum of the first preset percentage and the second preset percentage is 100%;

[0027] The first preset percentage is greater than the second preset percentage.

[0028] According to the abnormal battery screening method provided by the present invention, the step of charging each battery to be screened under a first preset battery capacity state according to a preset charging strategy, and determining the first DC resistance corresponding to each battery to be screened based on the first voltage change difference and the current change difference, includes:

[0029] When the battery capacity reaches the first preset battery capacity, obtain the third voltage corresponding to the battery to be screened;

[0030] All batteries to be screened are charged again based on the first constant current. After the first preset period, all batteries to be screened are charged again based on the second constant current. After the second preset period, the fourth voltage corresponding to each battery to be screened is obtained.

[0031] The first voltage change difference is determined based on the difference between the third voltage and the fourth voltage, and the current change difference is determined based on the difference between the first constant current and the second constant current.

[0032] The first DC resistance corresponding to each battery to be screened is determined based on the quotient of the first voltage change difference and the current change difference.

[0033] According to the abnormal battery screening method provided by the present invention, the step of charging each battery to be screened under a second preset battery capacity state according to the preset charging strategy, and determining the second DC resistance corresponding to each battery to be screened based on the second voltage change difference and the current change difference, includes:

[0034] When the battery capacity reaches the second preset battery capacity, obtain the fifth voltage corresponding to the battery to be screened;

[0035] All batteries to be screened are charged again based on the first constant current. After the first preset period, all batteries to be screened are charged again based on the second constant current. After the second preset period, the sixth voltage corresponding to each battery to be screened is obtained.

[0036] The second voltage change difference is determined based on the difference between the fifth voltage and the sixth voltage, and the current change difference is determined based on the difference between the first constant current and the second constant current.

[0037] The second DC resistance corresponding to each battery to be screened is determined based on the quotient of the second voltage change difference and the current change difference.

[0038] Secondly, an abnormal battery screening device is provided, comprising:

[0039] Determination unit: used to acquire the voltage change of each battery to be determined from the pre-charge stage to the aging stage, and to determine abnormal batteries whose voltage change is greater than a preset change based on the voltage change.

[0040] First charging unit: used to charge each battery to be screened under a first preset battery capacity state according to a preset charging strategy, and to determine the first DC resistance corresponding to each battery to be screened according to the first voltage change difference and the current change difference.

[0041] The second charging unit is used to charge each battery to be screened under the second preset battery capacity state according to the preset charging strategy, and to determine the second DC resistance corresponding to each battery to be screened according to the second voltage change difference and the current change difference.

[0042] Screening unit: used to determine the relative resistance ratio based on the first DC resistance and the second DC resistance corresponding to each battery to be screened, and to screen out abnormal batteries whose relative resistance ratio is not within a preset ratio range based on the relative resistance ratio.

[0043] The batteries to be screened are determined based on the batteries whose voltage change is less than or equal to a preset change.

[0044] Thirdly, the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the abnormal battery screening method.

[0045] Fourthly, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the abnormal battery screening method as described above.

[0046] This invention provides a method, apparatus, device, and readable storage medium for screening abnormal batteries. First, by comparing voltage changes from the pre-charge stage to the aging stage, this invention identifies batteries that may have voltage anomalies. Then, by charging the batteries using a preset charging strategy, potential abnormal faults are detected during the charging process. This allows for the detection of battery capacity and relative resistance ratio, thereby screening out abnormal batteries. This invention enables batch detection of battery anomalies, selecting healthy batteries for use from the source, greatly improving the user experience and preventing the use of abnormal batteries from reducing overall battery performance and shortening battery life. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0048] Figure 1 This is one of the flowcharts of the abnormal battery screening method provided by the present invention;

[0049] Figure 2 This is a schematic diagram of the process for identifying abnormal batteries whose voltage change exceeds a preset change amount, provided by the present invention.

[0050] Figure 3 This is the second flowchart of the abnormal battery screening method provided by the present invention;

[0051] Figure 4 This is the third flowchart of the abnormal battery screening method provided by the present invention;

[0052] Figure 5 This is the fourth flowchart of the abnormal battery screening method provided by the present invention;

[0053] Figure 6 This is a schematic diagram of the process for determining the first DC resistance provided by the present invention;

[0054] Figure 7 This is a schematic diagram of the process for determining the second DC resistance provided by the present invention;

[0055] Figure 8 This is a schematic diagram of the abnormal battery screening device provided by the present invention;

[0056] Figure 9 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0058] With the adjustment of industrial structure, the new energy battery industry has emerged and developed rapidly, becoming a key development area. Power batteries are increasingly used in electric vehicles, replacing gasoline and diesel fuels and becoming the driving force for electric vehicles. The development of battery energy storage, in particular, has propelled it to new heights. With the widespread use of power systems, the health status of power batteries has become an increasingly important concern.

[0059] However, current battery health conditions mainly suffer from the following problems: abnormal internal resistance, abnormal voltage, short battery life, and abnormal battery capacity. These problems can significantly shorten battery life during use, thereby affecting overall battery performance and reducing user experience. To solve the above technical problems, this invention provides an abnormal battery screening method, apparatus, device, and readable storage medium. Figure 1 This is one of the flowcharts illustrating the abnormal battery screening method provided by the present invention. The method includes:

[0060] Step 101: Obtain the voltage change of each battery to be determined from the pre-charge stage to the aging stage, and determine the abnormal batteries whose voltage change is greater than the preset change based on the voltage change.

[0061] Step 102: Charge each battery to be screened under the first preset battery capacity state according to the preset charging strategy, and determine the first DC resistance corresponding to each battery to be screened based on the first voltage change difference and the current change difference.

[0062] Step 103: Charge each battery to be screened under the second preset battery capacity state according to the preset charging strategy, and determine the second DC resistance corresponding to each battery to be screened based on the second voltage change difference and the current change difference.

[0063] Step 104: Determine the relative resistance ratio based on the first DC resistance and the second DC resistance corresponding to each battery to be screened, and screen out abnormal batteries whose relative resistance ratio is not within the preset ratio range based on the relative resistance ratio.

[0064] The batteries to be screened are determined based on the batteries whose voltage change is less than or equal to a preset change.

[0065] In step 101, those skilled in the art understand that the battery manufacturing process is divided into three stages: front-end electrode fabrication, mid-end cell packaging, and back-end battery activation. The battery activation stage involves fully activating the active materials and electrolyte in the battery to achieve stable electrochemical performance. The activation stage includes pre-charging, aging, and capacitance testing. Pre-charging is to activate the active materials of the positive and negative electrodes through the first few charge-discharge cycles, bringing them to their optimal operating condition. Aging allows for better electrolyte wetting, which is beneficial for stable battery performance. After aging, the active materials in the positive and negative electrodes can accelerate some side effects, such as gas production and electrolyte decomposition, allowing the electrochemical performance of the lithium battery to quickly reach stability. After a period of aging, battery consistency selection is performed. After formation, the cell voltage is unstable, and its measured value will deviate from the actual value. The voltage and internal resistance of the aged cells are more stable, making it easier to select batteries with high consistency.

[0066] Optionally, the batteries to be screened are determined based on the fact that the voltage change is less than or equal to a preset change. This invention enables batch processing so that all batteries to be screened enter the activation stage. The voltage change of each battery to be screened is obtained from the pre-charge stage to the aging stage. If the voltage change of the battery to be screened is greater than the preset change, the battery to be screened is considered an abnormal battery and is screened out for further testing, processing, adjustment or remanufacturing. If the voltage change of the battery to be screened is less than or equal to the preset change, the battery to be screened is considered to have passed this step and will proceed to the next step of screening.

[0067] In step 102, each battery to be screened under a first preset battery capacity state is charged according to a preset charging strategy. The first DC resistance corresponding to each battery to be screened is determined based on the first voltage change difference and the current change difference. The preset charging strategy is to record the current voltage, charge the battery based on a certain constant current, charge the battery again based on another constant current after a certain period of time, and obtain the current state voltage of the battery after another period of time. At this time, the first voltage change difference can be determined by the two voltage values ​​recorded before and after, and the current change difference can also be determined by the constant current values ​​during the two different charging times. With the first voltage change difference and the current change difference determined, the first DC resistance corresponding to each battery to be screened can be determined according to the formula for determining resistance in electrical engineering.

[0068] The first preset battery capacity state can be either a high-capacity state or a low-capacity state. Step 102 determines the first DC resistance of the battery in either the high-capacity or low-capacity state.

[0069] In step 103, each battery to be screened is charged according to the preset charging strategy under the second preset battery capacity state. The second DC resistance corresponding to each battery to be screened is determined according to the second voltage change difference and the current change difference. The second preset battery capacity state is different from the first preset battery capacity state. If step 102 tests the DC resistance under the high capacity state, then step 103 tests the DC resistance under the low capacity state. If step 102 tests the DC resistance under the low capacity state, then step 103 tests the DC resistance under the high capacity state.

[0070] Optionally, the preset charging strategy is the same as the charging strategy in step 102. Both involve recording the current voltage, charging the battery with a constant current, charging the battery again with another constant current after a certain period of time, and obtaining the current state voltage of the battery after another period of time. In this case, the second voltage change difference can be determined by the two voltage values ​​recorded before and after, and the current change difference can also be determined by the constant current values ​​during the two different charging times. With the second voltage change difference and the current change difference determined, the second DC resistance corresponding to each battery to be screened can be determined according to the formula for determining resistance in electrical engineering.

[0071] In step 104, a relative resistance ratio is determined based on the first DC resistance and the second DC resistance corresponding to each battery to be screened. Abnormal batteries whose relative resistance ratio is not within a preset ratio range are screened based on the relative resistance ratio. This invention can determine the relative resistance ratio based on the quotient of the first DC resistance and the second DC resistance corresponding to each battery to be screened, or it can determine the relative resistance ratio based on the quotient of the second DC resistance and the first DC resistance corresponding to each battery to be screened. In an optional embodiment, the preset ratio range is 1.05 to 1.2. If the quotient is 1.11, the battery to be screened is determined to be a normal battery. If the quotient is 0.87, the battery to be screened is determined to be an abnormal battery. If the quotient is 1.33, the battery to be screened is determined to be an abnormal battery.

[0072] This invention discloses a method for screening abnormal batteries. During the pre-charging and sorting process, a first sorting is performed based on the cell pre-charging, capacity grading, and self-discharge testing process. A second sorting is then performed by testing the DC internal resistance of the battery under both low and high capacitance conditions. Thus, after two sorting processes, all abnormal batteries are screened out. This invention can quickly screen out abnormal batteries, improve cell consistency, facilitate the assembly of cell modules and battery packs, and improve the health of power batteries by screening out batteries with abnormal internal resistance, abnormal voltage, short battery life, and abnormal capacitance.

[0073] This invention provides a method, apparatus, device, and readable storage medium for screening abnormal batteries. First, by comparing voltage changes from the pre-charge stage to the aging stage, this invention identifies batteries that may have voltage anomalies. Then, by charging the batteries using a preset charging strategy, potential abnormal faults are detected during the charging process. This allows for the detection of battery capacity and relative resistance ratio, thereby screening out abnormal batteries. This invention enables batch detection of battery anomalies, selecting healthy batteries for use from the source, greatly improving the user experience and preventing the use of abnormal batteries from reducing overall battery performance and shortening battery life.

[0074] Figure 2 This is a schematic diagram of the process for identifying abnormal batteries whose voltage change exceeds a preset change amount, provided by the present invention. The step of obtaining the voltage change amount of each battery to be identified from the pre-charge stage to the aging stage, and determining the abnormal battery whose voltage change exceeds the preset change amount based on the voltage change amount, includes:

[0075] Step 1011: Obtain the first voltage of each battery to be determined after the pre-charge stage, and obtain the second voltage of each battery to be determined after the aging stage;

[0076] Step 1012: Determine the voltage difference corresponding to each battery to be determined based on the first voltage and the second voltage;

[0077] Step 1013: Determine the voltage change for each battery to be determined based on the voltage difference and the first voltage.

[0078] In step 1011, the first voltage of each battery to be determined after the pre-charge stage is obtained, which is V1, and the second voltage of each battery to be determined after the aging stage is obtained, which is V2.

[0079] In step 1012, the voltage difference corresponding to each battery to be determined is determined based on the first voltage and the second voltage, and the voltage difference is V1-V2.

[0080] In step 1013, the voltage change amount corresponding to each battery to be determined is determined based on the voltage difference and the first voltage, and the voltage change amount is (V1-V2) / V2.

[0081] Furthermore, after obtaining the voltage difference corresponding to the battery, abnormal batteries with voltage changes greater than a preset change amount are determined based on the voltage change amount. The preset change amount is 3%. If the voltage change amount is 2%, the battery to be determined is considered a normal battery. If the voltage change amount is 5%, the battery to be determined is considered an abnormal battery.

[0082] Figure 3This is a second schematic flowchart of the abnormal battery screening method provided by the present invention. After determining abnormal batteries whose voltage change is greater than a preset change based on the voltage change, the method further includes:

[0083] Step 201: Identify all batteries whose voltage change is less than or equal to a preset change as batteries to be sorted.

[0084] Step 202: Obtain the nominal capacity of each battery to be sorted after the capacity grading stage, and identify the batteries to be sorted whose nominal capacity is not within the preset nominal capacity range as abnormal batteries.

[0085] Step 203: Identify the batteries to be sorted whose nominal capacity is within the preset nominal capacity range as the batteries to be screened.

[0086] In step 201, after determining abnormal batteries whose voltage changes are greater than a preset value based on the voltage change amount, the present invention directly identifies batteries whose voltage changes are less than or equal to the preset value as batteries to be screened. As a variation of the present invention, after identifying batteries whose voltage changes are less than or equal to the preset value, further sorting can be performed on these batteries. Specifically, all batteries whose voltage changes are less than or equal to the preset value are identified as batteries to be sorted. Through this embodiment, the present invention, based on the voltage change amount, further considers the impact of abnormal nominal capacity on the battery, and sorts out batteries with unqualified nominal capacity.

[0087] In step 202, the nominal capacity of each battery to be sorted after the capacity grading stage is obtained. Batteries whose nominal capacity is not within the preset nominal capacity range are identified as abnormal batteries. If the nominal capacity is not within the preset nominal capacity range, it is considered that the capacity of the battery is abnormal after the capacity grading stage. That is, batteries whose nominal capacity is not within the preset nominal capacity range are identified as abnormal batteries.

[0088] Optionally, the preset nominal capacity range is between the first nominal capacity and the second nominal capacity, for example, 100% nominal capacity to 103% nominal capacity. Further, the present invention uses a single cell of a lithium battery with a first nominal capacity of 15Ah as the screening object, then the second nominal capacity is 15.45Ah. In this case, the preset nominal capacity range is 15Ah to 15.45Ah.

[0089] In step 203, the batteries to be sorted that have a nominal capacity within a preset nominal capacity range are identified as the batteries to be screened. After the capacity grading stage, the battery capacity tends to stabilize. At this time, the nominal capacity of the battery should be within the preset nominal capacity range, which means it is a normal battery. Thus, the batteries to be sorted are identified as the batteries to be screened.

[0090] In an optional embodiment, the present invention takes the formed battery, charges it to 50%-100% of its capacity, and then lets it stand to remove batteries that are bloated, leaking, or burned.

[0091] Figure 4 This is the third flowchart of the abnormal battery screening method provided by the present invention. Before obtaining the voltage change of each battery to be determined from the pre-charge stage to the aging stage, it further includes:

[0092] Step 301: Perform pre-charge, aging and capacity testing operations on each original battery in sequence, and obtain the first internal resistance value of each original battery before the pre-charge stage, the second internal resistance value after the pre-charge stage, the third internal resistance value after the aging stage, and the fourth internal resistance value after the capacity testing stage.

[0093] Step 302: Determine that the first original battery with an internal resistance value greater than the preset internal resistance value is an abnormal battery; determine that the second original battery with an internal resistance value greater than the preset internal resistance value is an abnormal battery; determine that the third original battery with an internal resistance value greater than the preset internal resistance value is an abnormal battery; determine that the fourth original battery with an internal resistance value greater than the preset internal resistance value is an abnormal battery.

[0094] Step 303: Determine the original battery whose first internal resistance value, second internal resistance value, third internal resistance value, and fourth internal resistance value are all less than or equal to the preset internal resistance value as the battery to be determined.

[0095] In step 301, the present invention obtains the internal resistance values ​​of batteries at different stages using an internal resistance testing instrument. The present invention can perform pre-charging, aging, and capacity testing operations in batches. In an optional embodiment, the present invention uses 100 batteries as a batch and performs pre-charging, aging, and capacity testing operations sequentially to obtain the first internal resistance value of each original battery before the pre-charging stage, the second internal resistance value after the pre-charging stage, the third internal resistance value after the aging stage, and the fourth internal resistance value after the capacity testing stage.

[0096] In step 302, the preset internal resistance value can be 3mΩ. That is, if the first internal resistance value is greater than 3mΩ, the original battery corresponding to the first internal resistance value is determined to be an abnormal battery; if the second internal resistance value is greater than 3mΩ, the original battery corresponding to the second internal resistance value is determined to be an abnormal battery; if the third internal resistance value is greater than 3mΩ, the original battery corresponding to the third internal resistance value is determined to be an abnormal battery; and if the fourth internal resistance value is greater than 3mΩ, the original battery corresponding to the fourth internal resistance value is determined to be an abnormal battery.

[0097] In step 303, the original battery whose first internal resistance value, second internal resistance value, third internal resistance value and fourth internal resistance value are all less than or equal to the preset internal resistance value is determined as the battery to be determined. The present invention needs to ensure that the internal resistance value measured after the original battery has gone through any stage must be less than or equal to the preset internal resistance value. The original battery whose measured internal resistance value is less than or equal to the preset internal resistance value is determined as the battery to be determined.

[0098] Figure 5 This is a flowchart of the abnormal battery screening method provided by the present invention, which further includes the following steps before charging each battery to be screened in the second preset battery capacity state according to the preset charging strategy:

[0099] Step 401: Determine the first preset battery capacity based on the first preset percentage and the total battery capacity, and determine the second preset battery capacity based on the second preset percentage and the total battery capacity;

[0100] Step 402: Charge each battery to be screened based on a preset constant current until the battery capacity of each battery to be screened reaches the first preset battery capacity state.

[0101] Step 403: After determining the first DC resistance corresponding to each battery to be screened, discharge each battery to be screened based on a preset constant current until the battery capacity of each battery to be screened reaches the second preset battery capacity state.

[0102] The sum of the first preset percentage and the second preset percentage is 100%;

[0103] The first preset percentage is greater than the second preset percentage.

[0104] In step 401, the first preset battery capacity is determined based on the first preset percentage and the total battery capacity, and the second preset battery capacity is determined based on the second preset percentage and the total battery capacity. The sum of the first preset percentage and the second preset percentage is 100%. In this invention, the first preset percentage is between 10% and 90%, and the second preset percentage is between 90% and 10%. For example, if the first preset percentage is 10%, the second preset percentage is 90%. Or, for example, if the first preset percentage is 25%, the second preset percentage is 75%.

[0105] Optionally, if the first preset percentage is greater than the second preset percentage, then the first preset battery capacity corresponding to the first preset percentage is defined as high capacitance, and the second preset battery capacity corresponding to the second preset percentage is defined as low capacitance.

[0106] In step 402, each battery to be screened is charged based on a preset constant current until the battery capacity of each battery to be screened reaches a first preset battery capacity state. If the first preset battery capacity state is between 10.5Ah and 12.0Ah, optionally, a DC impedance DCR test is performed on each battery to be screened, and the battery cell is charged with a constant current of 7.5A until the battery capacity of each battery to be screened reaches between 10.5Ah and 12.0Ah. After reaching the first preset battery capacity state, each battery to be screened in the first preset battery capacity state can be charged according to a preset charging strategy, and the first DC resistance corresponding to each battery to be screened is determined according to the first voltage change difference and the current change difference.

[0107] In step 403, after determining the first DC resistance corresponding to each battery to be screened, each battery to be screened is discharged based on a preset constant current until the battery capacity of each battery to be screened reaches a second preset battery capacity state. After determining the first DC resistance corresponding to each battery to be screened, the battery to be screened is in a high capacity state. At this time, each battery to be screened needs to be discharged. Optionally, the second preset battery capacity state is 3.0Ah-4.5Ah, that is, the present invention discharges each battery to be screened based on a constant current of 7.5A until the battery capacity of each battery to be screened reaches 3.0Ah-4.5Ah. At this time, each battery to be screened in the second preset battery capacity state is charged according to the preset charging strategy. The second DC resistance corresponding to each battery to be screened is determined based on the second voltage change difference and the current change difference.

[0108] Figure 6 This is a flowchart illustrating the process of determining the first DC resistance provided by the present invention. The step of charging each battery to be screened at a first preset battery capacity state according to a preset charging strategy, and determining the first DC resistance corresponding to each battery to be screened based on the first voltage change difference and the current change difference, includes:

[0109] Step 1021: When the battery capacity reaches the first preset battery capacity, obtain the third voltage corresponding to the battery to be screened;

[0110] Step 1022: Continue charging all the batteries to be screened based on the first constant current. After the first preset time period, charge all the batteries to be screened again based on the second constant current. After the second preset time period, obtain the fourth voltage corresponding to each battery to be screened.

[0111] Step 1023: Determine the first voltage change difference based on the difference between the third voltage and the fourth voltage, and determine the current change difference based on the difference between the first constant current and the second constant current;

[0112] Step 1024: Determine the first DC resistance corresponding to each battery to be screened based on the quotient of the first voltage change difference and the current change difference.

[0113] In step 1021, when the battery capacity reaches the first preset battery capacity, the third voltage corresponding to the battery to be screened is obtained. In this invention, the battery cell can be charged with a constant current of 7.5A to a value between 10.5Ah and 12.0Ah. At this time, the third voltage corresponding to the battery to be screened is recorded as V3.

[0114] In step 1022, the first constant current is 75A, the first preset time period is 5s, the second constant current is 37.5A, and the second preset time period is 10s. At this time, all the batteries to be screened are charged based on the constant current of 75A. After 5s, all the batteries to be screened are charged again based on the constant current of 37.5A. After 10s, the fourth voltage corresponding to each battery to be screened is obtained, which is V4.

[0115] In step 1023, the first voltage change difference, namely V3-V4, is determined based on the difference between the third voltage and the fourth voltage, and the current change difference is determined based on the difference between the first constant current and the second constant current, wherein the current change difference is 37.5A.

[0116] In step 1024, the first DC resistance corresponding to each battery to be screened is determined based on the quotient of the first voltage change difference and the current change difference, wherein the quotient is (V3-V4) / 37.5.

[0117] Figure 7 This is a schematic flowchart of the process for determining the second DC resistance provided by the present invention. The step of charging each battery to be screened under a second preset battery capacity state according to the preset charging strategy, and determining the second DC resistance corresponding to each battery to be screened based on the second voltage change difference and the current change difference, includes:

[0118] Step 1031: When the battery capacity reaches the second preset battery capacity, obtain the fifth voltage corresponding to the battery to be screened;

[0119] Step 1032: Continue charging all the batteries to be screened based on the first constant current. After the first preset time period, charge all the batteries to be screened again based on the second constant current. After the second preset time period, obtain the sixth voltage corresponding to each battery to be screened.

[0120] Step 1033: Determine the second voltage change difference based on the difference between the fifth voltage and the sixth voltage, and determine the current change difference based on the difference between the first constant current and the second constant current;

[0121] Step 1034: Determine the second DC resistance corresponding to each battery to be screened based on the quotient of the second voltage change difference and the current change difference.

[0122] In step 1031, after determining the first DC resistance corresponding to each battery to be screened, each battery to be screened is discharged based on a preset constant current until the battery capacity of each battery to be screened reaches the second preset battery capacity state. When the battery capacity reaches the second preset battery capacity, the fifth voltage corresponding to the battery to be screened is obtained and denoted as V5.

[0123] In step 1032, the first constant current is 75A, the first preset time period is 5s, the second constant current is 37.5A, and the second preset time period is 10s. At this time, all the batteries to be screened are charged based on the constant current of 75A. After 5s, all the batteries to be screened are charged again based on the constant current of 37.5A. After 10s, the sixth voltage corresponding to each battery to be screened is obtained, which is V6.

[0124] In step 1033, the second voltage change difference, namely V5-V6, is determined based on the difference between the fifth voltage and the sixth voltage, and the current change difference is determined based on the difference between the first constant current and the second constant current, wherein the current change difference is 37.5A.

[0125] In step 1034, the second DC resistance corresponding to each battery to be screened is determined based on the quotient of the second voltage change difference and the current change difference, wherein the quotient is (V5-V6) / 37.5.

[0126] Figure 8 This is a schematic diagram of the abnormal battery screening device provided by the present invention. The present invention provides an abnormal battery screening device, including a determination unit 1: used to obtain the voltage change of each battery to be determined from the pre-charge stage to the aging stage, and to determine the abnormal battery whose voltage change is greater than a preset change based on the voltage change. The working principle of the determination unit 1 can be referred to the aforementioned step 101, and will not be repeated here.

[0127] The abnormal battery screening device further includes a first charging unit 2: used to charge each battery to be screened under a first preset battery capacity state according to a preset charging strategy, and to determine the first DC resistance corresponding to each battery to be screened according to the first voltage change difference and the current change difference. The working principle of the first charging unit 2 can be referred to the aforementioned step 102, and will not be repeated here.

[0128] The abnormal battery screening device further includes a second charging unit 3: used to charge each battery to be screened under the second preset battery capacity state according to the preset charging strategy, and to determine the second DC resistance corresponding to each battery to be screened according to the second voltage change difference and the current change difference. The working principle of the second charging unit 3 can be referred to the aforementioned step 103, and will not be repeated here.

[0129] The abnormal battery screening device further includes a screening unit 4: used to determine the relative resistance ratio based on the first DC resistance and the second DC resistance corresponding to each battery to be screened, and to screen out abnormal batteries whose relative resistance ratio is not within a preset ratio range. The working principle of the screening unit 4 can be referred to the aforementioned step 104, and will not be repeated here.

[0130] The batteries to be screened are determined based on the batteries whose voltage change is less than or equal to a preset change.

[0131] This invention provides a method, apparatus, device, and readable storage medium for screening abnormal batteries. First, by comparing voltage changes from the pre-charge stage to the aging stage, this invention identifies batteries that may have voltage anomalies. Then, by charging the batteries using a preset charging strategy, potential abnormal faults are detected during the charging process. This allows for the detection of battery capacity and relative resistance ratio, thereby screening out abnormal batteries. This invention enables batch detection of battery anomalies, selecting healthy batteries for use from the source, greatly improving the user experience and preventing the use of abnormal batteries from reducing overall battery performance and shortening battery life.

[0132] Figure 9 This is a schematic diagram of the structure of the electronic device provided by the present invention. For example... Figure 9As shown, the electronic device may include: a processor 910, a communication interface 920, a memory 930, and a communication bus 940, wherein the processor 910, the communication interface 920, and the memory 930 communicate with each other through the communication bus 940. The processor 910 can call logic instructions in the memory 930 to execute an abnormal battery screening method. This method includes: acquiring the voltage change of each battery to be determined from the pre-charge stage to the aging stage; determining abnormal batteries whose voltage change is greater than a preset change based on the voltage change; charging each battery to be screened under a first preset battery capacity state according to a preset charging strategy; determining a first DC resistance corresponding to each battery to be screened based on a first voltage change difference and a current change difference; charging each battery to be screened under a second preset battery capacity state according to the preset charging strategy; determining a second DC resistance corresponding to each battery to be screened based on a second voltage change difference and the current change difference; determining a relative resistance ratio based on the first DC resistance and the second DC resistance corresponding to each battery to be screened; and screening abnormal batteries whose relative resistance ratio is not within a preset ratio range based on the relative resistance ratio; the batteries to be screened are determined based on batteries whose voltage change is less than or equal to the preset change.

[0133] Furthermore, the logical instructions in the aforementioned memory 930 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0134] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute an abnormal battery screening method provided by the above methods. The method includes: acquiring the voltage change of each battery to be determined from the pre-charge stage to the aging stage; determining abnormal batteries whose voltage change is greater than a preset change based on the voltage change; charging each battery to be screened under a first preset battery capacity state according to a preset charging strategy; determining a first DC resistance corresponding to each battery to be screened based on a first voltage change difference and a current change difference; charging each battery to be screened under a second preset battery capacity state according to the preset charging strategy; determining a second DC resistance corresponding to each battery to be screened based on a second voltage change difference and the current change difference; determining a relative resistance ratio based on the first DC resistance and the second DC resistance corresponding to each battery to be screened; and screening abnormal batteries whose relative resistance ratio is not within a preset ratio range based on the relative resistance ratio; the batteries to be screened are determined based on the batteries to be determined whose voltage change is less than or equal to the preset change.

[0135] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements an abnormal battery screening method provided by the above methods. The method includes: acquiring the voltage change of each battery to be determined from a pre-charge stage to an aging stage; determining abnormal batteries whose voltage change is greater than a preset change based on the voltage change; charging each battery to be screened under a first preset battery capacity state according to a preset charging strategy; determining a first DC resistance corresponding to each battery to be screened based on a first voltage change difference and a current change difference; charging each battery to be screened under a second preset battery capacity state according to the preset charging strategy; determining a second DC resistance corresponding to each battery to be screened based on a second voltage change difference and the current change difference; determining a relative resistance ratio based on the first DC resistance and the second DC resistance corresponding to each battery to be screened; and screening abnormal batteries whose relative resistance ratio is not within a preset ratio range based on the relative resistance ratio; wherein the batteries to be screened are determined based on batteries whose voltage change is less than or equal to the preset change.

[0136] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0137] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0138] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An abnormal battery screening method, characterized by, The method comprises the following steps: acquiring a voltage variation of each battery to be determined after a pre-charging stage to an aging stage, and determining an abnormal battery with a voltage variation greater than a preset variation based on the voltage variation; charging each battery to be screened in a first preset battery capacity state according to a preset charging strategy, and determining a first direct current resistance corresponding to each battery to be screened based on a first voltage variation difference and a current variation difference; charging each battery to be screened in a second preset battery capacity state according to the preset charging strategy, and determining a second direct current resistance corresponding to each battery to be screened based on a second voltage variation difference and the current variation difference; the first preset battery capacity state is different from the second preset battery capacity state; determining a relative resistance ratio based on the first direct current resistance and the second direct current resistance corresponding to each battery to be screened, and screening an abnormal battery with a relative resistance ratio not within a preset ratio interval based on the relative resistance ratio; the battery to be screened is determined based on the battery to be determined with a voltage variation less than or equal to a preset variation.

2. The method of claim 1, wherein, The method comprises the following steps: acquiring a first voltage of each battery to be determined after a pre-charging stage, and acquiring a second voltage of each battery to be determined after an aging stage; determining a voltage difference corresponding to each battery to be determined based on the first voltage and the second voltage; determining the voltage variation corresponding to each battery to be determined based on the voltage difference and the first voltage.

3. The abnormal battery screening method according to claim 1 or 2, characterized by, After determining the abnormal battery with the voltage variation greater than the preset variation based on the voltage variation, the method further comprises the following steps: determining all the batteries to be determined with a voltage variation less than or equal to a preset variation as batteries to be sorted; acquiring a nominal capacity of each battery to be sorted after a capacity sorting stage, and determining an abnormal battery with a nominal capacity not within a preset nominal capacity interval; determining the battery to be screened as the battery to be sorted with a nominal capacity within the preset nominal capacity interval.

4. The method of claim 1, wherein the step of screening for abnormal batteries is performed by a method comprising: Before acquiring the voltage variation of each battery to be determined after the pre-charging stage to the aging stage, the method further comprises the following steps: sequentially performing pre-charging, aging, and capacity sorting operations on each original battery respectively, and acquiring a first internal resistance value of each original battery before the pre-charging stage, a second internal resistance value of each original battery after the pre-charging stage, a third internal resistance value of each original battery after the aging stage, and a fourth internal resistance value of each original battery after the capacity sorting stage; determining an original battery with a first internal resistance value greater than a preset internal resistance value as an abnormal battery, an original battery with a second internal resistance value greater than a preset internal resistance value as an abnormal battery, an original battery with a third internal resistance value greater than a preset internal resistance value as an abnormal battery, and an original battery with a fourth internal resistance value greater than a preset internal resistance value as an abnormal battery; determining an original battery with the first internal resistance value, the second internal resistance value, the third internal resistance value, and the fourth internal resistance value all less than or equal to a preset internal resistance value as a battery to be determined.

5. The method of claim 1, wherein the step of screening for abnormal batteries is performed by a method comprising: Before charging each battery to be screened in a second preset battery capacity state according to the preset charging strategy, the method further comprises the following steps: The first preset battery capacity is determined according to the first preset percentage and the total capacity of the battery, and the second preset battery capacity is determined according to the second preset percentage and the total capacity of the battery; Each battery to be screened is charged based on a preset constant current until the battery capacity of each battery to be screened reaches a first preset battery capacity state; After determining the first direct current resistance corresponding to each battery to be screened, each battery to be screened is discharged based on a preset constant current until the battery capacity of each battery to be screened reaches a second preset battery capacity state; The sum of the first preset percentage and the second preset percentage is 100%; The first preset percentage is greater than the second preset percentage.

6. The method of claim 1, wherein the step of screening for abnormal batteries is performed by a method comprising: The first preset battery capacity state, each battery to be screened is charged according to a preset charging strategy, the first voltage change difference and the current change difference are determined, and the first direct current resistance corresponding to each battery to be screened is determined, including: In the case that the battery capacity reaches the first preset battery capacity, the third voltage corresponding to the battery to be screened is obtained; After the first preset time period, all the batteries to be screened are charged again based on the second constant current, and after the second preset time period, the fourth voltage corresponding to each battery to be screened is obtained; The first voltage change difference is determined according to the difference between the third voltage and the fourth voltage, and the current change difference is determined according to the difference between the first constant current and the second constant current; The first direct current resistance corresponding to each battery to be screened is determined according to the quotient of the first voltage change difference and the current change difference.

7. The method of claim 1, wherein the step of screening for abnormal batteries is performed by a method comprising: The second preset battery capacity state, each battery to be screened is charged according to the preset charging strategy, the second voltage change difference and the current change difference are determined, and the second direct current resistance corresponding to each battery to be screened is determined, including: In the case that the battery capacity reaches the second preset battery capacity, the fifth voltage corresponding to the battery to be screened is obtained; After the first preset time period, all the batteries to be screened are charged again based on the second constant current, and after the second preset time period, the sixth voltage corresponding to each battery to be screened is obtained; The second voltage change difference is determined according to the difference between the fifth voltage and the sixth voltage, and the current change difference is determined according to the difference between the first constant current and the second constant current; The second direct current resistance corresponding to each battery to be screened is determined according to the quotient of the second voltage change difference and the current change difference.

8. An abnormal battery screening device, characterized by, Including: The determination unit is used to obtain the voltage change amount of each battery to be determined after the pre-charging stage to the aging stage, and determine the abnormal battery with the voltage change amount greater than the preset change amount; The first charging unit is used to charge each battery to be screened in a first preset battery capacity state according to a preset charging strategy, and determine the first direct current resistance corresponding to each battery to be screened according to a first voltage change difference and a current change difference; The second charging unit is configured to charge each battery to be screened in a second preset battery capacity state according to the preset charging strategy, and determine a second DC resistance corresponding to each battery to be screened according to a second voltage variation difference and the current variation difference; The first preset battery capacity state is different from the second preset battery capacity state; The screening unit is configured to determine a relative resistance ratio according to the first DC resistance and the second DC resistance corresponding to each battery to be screened, and screen an abnormal battery whose relative resistance ratio is not within a preset ratio interval according to the relative resistance ratio. The battery to be screened is determined according to the battery to be determined whose voltage variation is less than or equal to a preset variation.

9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the program to implement the abnormal battery screening method in any one of claims 1-7.

10. A non-transitory computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the abnormal battery screening method in any one of claims 1-7.

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