A method, apparatus for battery sorting and a battery

Abstract

The application discloses a battery sorting method and device and a battery. The method comprises collecting static sorting parameters of single batteries to be sorted, screening a first part of the single batteries based on a pre-prepared static sorting standard, and screening out single batteries in the first part of the single batteries that do not meet dynamic sorting conditions in a set dynamic sorting process based on a set dynamic sorting process and corresponding dynamic sorting conditions. The application screens out single batteries that do not meet discrete requirements in different dynamic processes in terms of voltage and temperature by screening the single batteries obtained after static sorting based on the set dynamic sorting process and the corresponding dynamic sorting conditions, so as to ensure dynamic consistency of the single batteries after grouping and meet the discharge capacity requirement of the battery pack.

Description

Technical Field

[0001] This application belongs to the field of battery technology, and in particular relates to a method, apparatus and a battery for battery sorting. Background Technology

[0002] The demand for batteries in the military market is constantly increasing, and the operating conditions of batteries are becoming increasingly extreme. The consistency of individual battery cells after assembly is a crucial factor affecting the performance of the battery pack. In order to achieve the required discharge capacity, the consistency requirements for individual battery cells after assembly are quite stringent. For example, during the charge and discharge dynamic process under low temperature conditions of -45℃ and high temperature conditions of 55℃, it is necessary to ensure that the battery pack can meet the standard of continuous pulse discharge at a high current of kiloamperes.

[0003] When there are significant inconsistencies among the individual cells in a battery pack, continuous charge-discharge cycles will amplify these differences, leading to accelerated battery pack degradation and ultimately premature failure, preventing the battery pack from reaching its required discharge capacity. Currently, to ensure consistency among individual cells after pack assembly, static sorting is mainly used to guarantee the consistency of state parameters of each individual cell under the condition of no external influence. However, static sorting methods cannot filter out individual cells that affect the discharge capacity of the battery pack during dynamic processes; that is, static sorting methods cannot guarantee the dynamic consistency of individual cells after pack assembly. Summary of the Invention

[0004] The purpose of this application is to provide a battery sorting method, device, and battery. By sorting individual cells obtained after static sorting and then filtering out individual cells whose voltage and temperature do not meet the discrete requirements under different dynamic processes based on a set dynamic screening process and corresponding dynamic screening conditions, the dynamic consistency of the individual cells after being assembled into a battery pack and the discharge capacity of the battery pack meet the requirements are ensured.

[0005] In a first aspect, this application provides a method for battery sorting, the method comprising: Collect static sorting parameters of the individual cells to be sorted, and select the first batch of individual cells based on the pre-defined static sorting criteria; Based on the set dynamic screening process and corresponding dynamic screening conditions, individual cells in the first part of the cell pool that do not meet the dynamic screening conditions in terms of voltage and temperature during the set dynamic screening process are screened out.

[0006] In one possible implementation, the static sorting parameters include capacity, internal resistance, open-circuit voltage, and self-discharge rate, and the static sorting criteria include set ranges for capacity difference, internal resistance difference, voltage difference, and self-discharge rate.

[0007] In one possible implementation, the dynamic screening process is carried out in a charge-discharge test device including multiple probes, wherein the individual cells in the charge-discharge test device are connected in series via multiple probes, and the probes are used to detect and control the current and voltage changes of the individual cells in the charge-discharge test device during the charge-discharge process.

[0008] In one possible implementation, the dynamic screening process is a charge / discharge process at a set charge / discharge rate, and the dynamic screening conditions include high temperature values ​​that do not meet the discrete requirements during the set dynamic screening process, high voltage values ​​that do not meet the discrete requirements during the charging process, and low voltage values ​​that do not meet the discrete requirements during the discharging process.

[0009] In one possible implementation, the step of filtering out individual cells in the first portion of individual cells whose voltage and temperature do not meet the dynamic screening conditions during the set dynamic screening process, based on a set dynamic screening process and corresponding dynamic screening conditions, includes at least one of the following steps: Through the first dynamic screening process, individual cells in the first part of the individual cells whose voltage and temperature do not meet the discrete requirements at the end of the set charge and discharge time are screened out, and the second part of the individual cells are obtained. Through the second dynamic screening process, individual cells in the second part of the individual cells whose voltage and temperature at the set state of charge (SOC) end do not meet the discrete requirements are screened out, and the third part of the individual cells are obtained. Through the third dynamic screening process, individual cells in the third part of the individual cells whose voltage and temperature at the end of each pulse under the set pulse discharge conditions do not meet the discrete requirements are screened out, thus obtaining the fourth part of the individual cells.

[0010] In one possible implementation, the first dynamic filtering process is as follows: The first batch of individual batteries are charged to a set charging time at a set charging rate, and the battery voltage and battery temperature at the end of the set charging time are collected to generate a distribution map of battery voltage and battery temperature at the end of the charging time. Based on the preset discrete requirements, individual cells that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at the charging end are screened out, resulting in the first batch of individual cells after preliminary screening. The first batch of individual cells after preliminary screening are discharged at a set discharge rate for a set discharge duration, and the battery voltage and battery temperature at the end of the set discharge duration are collected to generate a distribution map of battery voltage and battery temperature at the end of the discharge. Based on the preset discrete requirements, individual cells that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at the discharge end are screened out, resulting in the second batch of individual cells.

[0011] In one possible implementation, the second dynamic filtering process is as follows: The second part of the single cells is charged from 0% SOC to 100% SOC at a set charging rate, and the battery voltage and battery temperature at different SOC ends are collected during the charging process to generate a distribution map of battery voltage and battery temperature at different SOC ends during the charging process. Based on the preset discrete requirements, individual cells that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at different SOC ends during the charging process are screened out, and the screening is stopped after the set stopping condition is reached, resulting in the second part of individual cells after preliminary screening. The second batch of individual cells after preliminary screening are discharged from 100% SOC to 0% SOC at a set discharge rate, and the battery voltage and battery temperature at different SOC ends during the discharge process are collected to generate a distribution map of battery voltage and battery temperature at different SOC ends during the discharge process. Based on preset discrete requirements, individual cells that do not meet the discrete requirements in the distribution map of battery voltage and battery temperature at different SOC ends during the discharge process are screened out, and the screening stops after the set stopping condition is reached, thus obtaining the third part of individual cells.

[0012] In one possible implementation, the third dynamic filtering process is as follows: After charging the third group of individual cells to 100% SOC at a set charging rate, pulse discharge is performed on the third group of individual cells at a set pulse discharge rate until a set stop condition is reached. The pulse discharge rate is set based on the required battery discharge capacity. The battery voltage and temperature at the end of each pulse during the pulse discharge process are collected, and a distribution map of the battery voltage and temperature at the end of each pulse during the pulse discharge process is generated. Based on the preset discrete requirements, the individual cells corresponding to low voltage values ​​and high temperature values ​​that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at the end of each pulse during the pulse discharge process are screened out, resulting in the fourth part of individual cells.

[0013] In one possible implementation, the stopping condition includes at least one of the following: The remaining individual cells have reached the set SOC; The proportion of the remaining individual cells in the first batch of individual cells does not meet the set ratio.

[0014] In one possible implementation, the pulse discharge rate during the third dynamic screening process is higher than the charge / discharge rate during the first / second dynamic screening processes.

[0015] In one possible implementation, during the first / second / third dynamic screening process, after each screening of individual cells that do not meet the discrete requirements, if the screening ratio does not reach the set ratio, then another portion of individual cells are screened out again according to the set screening conditions until the screening ratio reaches the set ratio. In the first / second / third dynamic screening process, each of the corresponding charging or discharging processes corresponds to a preset remaining ratio. If the proportion of the remaining single cells in the first part of the single cells after a certain screening is less than the preset remaining ratio corresponding to the current charging or discharging process, the current screening will not be performed and the current charging or discharging process will end.

[0016] In one possible implementation, the number of the first portion of individual cells is twice the number of individual cells required.

[0017] Secondly, this application provides a battery comprising a single cell obtained by the method described in the first aspect.

[0018] Thirdly, this application provides a battery sorting device, including at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform a battery sorting method as described in any of the first aspects of this application.

[0019] Fourthly, embodiments of this application also provide a computer-readable storage medium that, when the instructions in the computer-readable storage medium are executed by a processor of a terminal device, enables the terminal device to perform the battery sorting method as described in any of the first aspects of this application.

[0020] The technical solutions provided by the embodiments of this application bring at least the following beneficial effects: This application provides a battery sorting method, apparatus, and a battery. The method involves dynamic sorting of individual cells obtained after static sorting. The dynamic sorting includes a first, second, and third dynamic screening process. The first dynamic screening process initially removes individual cells with abnormal internal resistance and dynamic voltage at the end of a set charge / discharge time after activation. The second dynamic screening process removes individual cells whose voltage and temperature at the end of a set SOC state do not meet the discrete requirements. Finally, the third dynamic screening process removes individual cells whose voltage and temperature at the end of each pulse under a set pulse discharge condition do not meet the discrete requirements. Through the above dynamic sorting process, the dynamic consistency of the individual cells after assembly and the discharge capacity of the battery pack under the required operating conditions can be guaranteed. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings introduced below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A flowchart of a battery sorting method provided in this application embodiment; Figure 2 A schematic diagram of the battery voltage distribution at the charging end of the first dynamic screening process provided in this application embodiment; Figure 3 A schematic diagram of the battery voltage distribution at the discharge end of the first dynamic screening process provided in this application embodiment; Figure 4 A schematic diagram showing the distribution of battery voltage when charged to 100% SOC during the second dynamic screening process provided in this application embodiment; Figure 5 A schematic diagram of the battery temperature distribution during the second dynamic screening process provided in this application embodiment, when the battery is charged to 100% SOC; Figure 6 This is a schematic diagram of a battery sorting device provided in an embodiment of this application. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. The described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0024] The demand for batteries in the military market is constantly increasing, and the operating conditions of batteries are becoming increasingly extreme. The consistency of individual battery cells after assembly is a crucial factor affecting the performance of the battery pack. In order to achieve the required discharge capacity, the consistency requirements for individual battery cells after assembly are quite stringent. For example, during the charge and discharge dynamic process under low temperature conditions of -45℃ and high temperature conditions of 55℃, it is necessary to ensure that the battery pack can meet the standard of continuous pulse discharge at a high current of kiloamperes.

[0025] When there are significant inconsistencies among the individual cells in a battery pack, continuous charge-discharge cycles will amplify these differences, leading to accelerated battery pack degradation and ultimately premature failure, preventing the battery pack from reaching its required discharge capacity. Currently, to ensure consistency among individual cells after pack assembly, static sorting is mainly used to guarantee the consistency of state parameters of each individual cell under the condition of no external influence. However, static sorting methods cannot filter out individual cells that affect the discharge capacity of the battery pack during dynamic processes; that is, static sorting methods cannot guarantee the dynamic consistency of individual cells after pack assembly.

[0026] In view of the above problems, this application provides a battery sorting method, device and a battery, which performs dynamic sorting on the individual cells obtained after static sorting. Based on the set dynamic screening process and corresponding dynamic screening conditions, individual cells whose voltage and temperature do not meet the discrete requirements under different dynamic processes are screened out, so as to ensure the dynamic consistency of the individual cells after being assembled into a group and to ensure that the discharge capacity of the battery group meets the requirements.

[0027] like Figure 1 The diagram shown is a flowchart of a battery sorting method provided in an embodiment of this application, including the following steps: Step 11: Collect the static sorting parameters of the individual cells to be sorted, and select the first batch of individual cells based on the pre-defined static sorting criteria. Static consistency refers to the consistency of the state parameters of each individual battery cell under the condition of no external influence. It can characterize the health level and the degree of similarity of charge state of each individual battery cell. Therefore, before combining multiple batteries into a battery pack according to the required voltage and capacity, in order to ensure the battery pack's capacity and cycle life during use, it is necessary to perform static sorting on the individual batteries to be sorted, so that the static sorting parameters of the sorted individual batteries tend to be consistent, thus ensuring static consistency.

[0028] In this application, static sorting and grouping of individual cells to be sorted are performed based on static sorting parameters such as capacity, internal resistance, open circuit voltage (OCV) and self-discharge rate, as well as static sorting standards pre-defined according to requirements.

[0029] As a feasible implementation method, static sorting parameters of the individual cells to be sorted are collected, and a first batch of individual cells is selected based on pre-defined static sorting criteria, including: Under set room temperature conditions, the capacity, internal resistance, open circuit voltage, and self-discharge rate of the individual cells to be sorted were collected. Based on the set capacity difference range, internal resistance difference range, voltage difference range, and self-discharge rate range, individual cells that exceed the set capacity difference range, internal resistance difference range, voltage difference range, and self-discharge rate range are screened out from the individual cells to be sorted, thus obtaining the first batch of individual cells.

[0030] Step 12: Based on the set dynamic screening process and corresponding dynamic screening conditions, filter out individual cells in the first part of the individual cells whose voltage and temperature do not meet the dynamic screening conditions during the set dynamic screening process.

[0031] After the individual cells sorted by the static sorting method are assembled into a battery pack, their performance may change significantly under the same working conditions as energy input and output. This results in differences in the energy input and output response of each individual cell, causing changes in the capacity, internal resistance, and charge-discharge curve of the individual cells.

[0032] When the performance of a single cell within a battery pack differs from that of other cells, the battery pack will lack consistency during dynamic processes. Insufficient consistency among the individual cells within the battery pack can lead to a "bucket effect" during charging and discharging, resulting in high charging and low discharging, thus accelerating battery lifespan degradation.

[0033] For example, inconsistent cell capacities in a battery pack can lead to inconsistent depths of discharge. Smaller, lower-performance cells will reach full charge earlier, while larger, higher-performance cells will not. This results in undercharging of the entire battery pack, leading to insufficient capacity and reduced performance. Therefore, both static and dynamic consistency must be considered when sorting individual cells. Through static and dynamic screening processes, a battery pack that satisfies both static and dynamic consistency can be obtained.

[0034] In one or more embodiments, the dynamic screening process is a charge / discharge process at a set charge / discharge rate, and the dynamic screening conditions include high temperature values ​​that do not meet the discrete requirements during the set dynamic screening process, high voltage values ​​that do not meet the discrete requirements during the charging process, and low voltage values ​​that do not meet the discrete requirements during the discharging process.

[0035] In the above dynamic screening conditions, the purpose of filtering out individual cells with high temperature values ​​that do not meet the discrete requirements during the dynamic screening process is to filter out individual cells with excessively high temperatures during charging and discharging, so as to avoid performance degradation of the battery pack due to abnormal temperatures of individual cells. The purpose of filtering out high voltage values ​​that do not meet the discrete requirements during charging is to filter out individual cells that will be fully charged too early during the charging process. The purpose of filtering out low voltage values ​​that do not meet the discrete requirements during discharging is to filter out individual cells that will be discharged too early during the discharging process.

[0036] In this embodiment of the application, the above-mentioned dynamic screening conditions are used to screen out individual cells with large temperature and voltage dispersions during the set dynamic screening process, so that the battery pack composed of the screened individual cells can meet the discharge requirements in different dynamic processes.

[0037] In one or more embodiments, the step of filtering out individual cells in the first portion of individual cells whose voltage and temperature do not meet the dynamic screening conditions during the set dynamic screening process, based on a set dynamic screening process and corresponding dynamic screening conditions, includes at least one of the following steps: A), B), and C). A) Through the first dynamic screening process, individual cells in the first part of the individual cells whose voltage and temperature do not meet the discrete requirements at the end of the set charge and discharge time are screened out, and the second part of the individual cells are obtained. Specifically, the first dynamic screening process includes steps A1) and A2) as follows: A1) 1) Charge the first batch of individual batteries to a set charging time using a set charging rate, and collect the battery voltage and battery temperature at the end of the set charging time to generate a distribution map of battery voltage and battery temperature at the end of the charging time. 2) Based on the preset discrete requirements, filter out the individual cells corresponding to high voltage and high temperature values ​​that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at the charging end, and obtain the first part of individual cells after preliminary filtering. A2) 1) Discharge the first batch of individual cells after preliminary screening to a set discharge time using a set discharge rate, and collect the battery voltage and battery temperature at the end of the set discharge time to generate a distribution map of battery voltage and battery temperature at the end of the discharge. 2) Based on the preset discrete requirements, filter out the individual cells corresponding to low voltage values ​​and high temperature values ​​that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at the discharge end, and obtain the second part of individual cells.

[0038] It should be noted that the first batch of individual cells needs to be discharged to the set cutoff voltage before performing step A above. Furthermore, the charge and discharge time set in the first dynamic screening process in this application is usually on the order of minutes, which is insufficient to fully charge the battery.

[0039] Through the first dynamic screening process, the battery can be dynamically activated. Under the condition of charge and discharge time on the order of minutes, individual cells with high internal resistance and abnormal dynamic voltage are screened out from the first batch of individual cells. The remaining normal cells are then subjected to subsequent tests.

[0040] Optionally, if the above-set charge / discharge rate is 1C and the above-set charge / discharge duration is 1 minute of charging and 1 minute of discharging, then after obtaining the first batch of individual cells screened based on the aforementioned static sorting method, the first batch of individual cells can be charged at a 1C charging rate for 1 minute to obtain the distribution map of battery voltage and battery temperature at the end of charging (i.e., when charging to 1 minute).

[0041] like Figure 2 The diagram shown illustrates the battery voltage distribution at the charging end of the first dynamic screening process provided in this embodiment. It can be seen that... Figure 2 The cells highlighted in the middle are those whose voltage at the end of the charging process does not meet the discrete requirements after being charged for the set time. In other words, these are cells with excessively high voltage after being charged for 1 minute at a 1C charging rate. These cells need to be removed. After removing these cells and the cells with high temperature values ​​that do not meet the discrete requirements from the first batch of cells, we can obtain the first batch of cells after preliminary removal.

[0042] After obtaining the first batch of individual cells after preliminary screening, the first batch of individual cells after preliminary screening is discharged at a 1C discharge rate for 1 minute to obtain the distribution map of battery voltage and battery temperature at the end of discharge (i.e., after 1 minute of discharge).

[0043] like Figure 3 The diagram shown is a schematic representation of the battery voltage distribution at the discharge end of the first dynamic screening process provided in this embodiment. It can be seen that... Figure 3 The cells highlighted in the middle are those whose voltage at the end of the discharge does not meet the discrete requirements after being discharged for a set time. In other words, cells whose voltage is too low after discharging for 1 minute at a 1C discharge rate. These cells need to be removed. After removing these cells and the cells with high temperature values ​​that do not meet the discrete requirements from the first batch of cells after the initial screening, the first batch of cells can be obtained.

[0044] B)

[0045] Through the second dynamic screening process, individual cells in the second part of the individual cells whose voltage and temperature at the set state of charge (SOC) end do not meet the discrete requirements are screened out, and the third part of the individual cells are obtained. Specifically, the second dynamic screening process includes steps B1) and B2) as follows: B1) 1) Charge the second part of individual cells from 0% SOC to 100% SOC at the set charging rate, and collect the battery voltage and battery temperature at different SOC ends during the charging process to generate a distribution map of battery voltage and battery temperature at different SOC ends during the charging process. 2) Based on the preset discrete requirements, the individual cells corresponding to high voltage and high temperature values ​​that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at different SOC ends during the charging process are screened out, and the screening is stopped after the set stopping condition is reached, to obtain the second part of individual cells after preliminary screening. B2) 1) Discharge the second batch of individual cells after preliminary screening from 100% SOC to 0% SOC at the set discharge rate, and collect the battery voltage and battery temperature at different SOC ends during the discharge process to generate a distribution map of battery voltage and battery temperature at different SOC ends during the discharge process. 2) Based on the preset discrete requirements, the individual cells corresponding to low voltage values ​​and high temperature values ​​that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at different SOC ends during the discharge process are screened out, and the screening is stopped after the set stopping condition is reached, thus obtaining the third part of individual cells.

[0046] It should be noted that the charge of the second portion of the individual cells obtained in step A) needs to be discharged to the set cutoff voltage before performing step B above.

[0047] In the second dynamic screening process, the characteristics of the battery at different SOCs are activated by charging the battery to a set SOC or discharging the battery to a set SOC at a set charge / discharge rate. At different SOC ends (a certain SOC state selected from 0% to 100% SOC), individual cells whose battery voltage and battery temperature do not meet the discrete requirements are screened out, leaving the batteries with better consistency.

[0048] Optionally, if the above-mentioned charge / discharge rate is set to 1C, and the battery voltage and battery temperature at different SOC ends are collected at a sampling interval of 20% SOC, then after obtaining the second part of individual cells screened based on the first dynamic screening process, the second part of individual cells can be charged from 0% SOC to 20% SOC at a 1C charging rate to generate a distribution map of battery voltage and battery temperature when the battery SOC reaches 20% SOC. Then, individual cells in the second part of individual cells that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at 20% SOC are screened out, resulting in the second part of individual cells that have been screened out once.

[0049] After obtaining the second batch of single cells that have been screened once, the second batch of single cells that have been screened once are then subjected to the above charging and screening process again, starting from 20% SOC at 20% intervals. That is, the second batch of single cells is charged to 20%, 40%, 60%, 80%, and 100% SOC, and the operation of screening out the single cells with high voltage and high temperature values ​​that do not meet the discrete requirements is performed 5 times, to obtain the second batch of single cells that have been initially screened.

[0050] like Figure 4 The diagram shown illustrates the voltage distribution of the battery when charged to 100% SOC during the second dynamic screening process provided in this embodiment. It can be seen that... Figure 4 The cells highlighted in the middle are the second batch of individual cells that, after being screened four times, are charged from 80% SOC to 100% SOC at a 1C charging rate. These cells do not meet the high voltage value required for dispersion and need to be screened out.

[0051] like Figure 5 The diagram shown illustrates the temperature distribution of the battery during the second dynamic screening process, charged to 100% SOC, according to an embodiment of this application. It can be seen that... Figure 5 The cells highlighted in the middle are the second batch of individual cells that, after being screened four times, are charged from 80% SOC to 100% SOC at a 1C charging rate. The high temperature values ​​that do not meet the discrete requirements are the individual cells that need to be screened out.

[0052] After completing the five screening processes described above during the charging process, the second batch of cells initially screened out are discharged from 100% SOC to 0% SOC at a 1C discharge rate. During the discharge process, the cells corresponding to low voltage and high temperature values ​​that do not meet the discrete requirements are screened out five times in the order of 80%, 60%, 40%, 20%, and 0% SOC, at 20% SOC intervals, to obtain the third batch of cells.

[0053] It should be noted that during the charging and discharging process of the second dynamic screening process, the number of screenings or the SOC state corresponding to each screening can be limited according to the actual situation, and is not limited to 5 times or screening at intervals of 20% SOC. This application does not limit this.

[0054] C)

[0055] Through the third dynamic screening process, individual cells in the third part of the individual cells whose voltage and temperature at the end of each pulse under the set pulse discharge conditions do not meet the discrete requirements are screened out, thus obtaining the fourth part of the individual cells.

[0056] It should be noted that the third portion of the individual cells obtained in step B) needs to be fully charged before performing step C).

[0057] Specifically, the third dynamic filtering process is as follows: 1) After charging the third part of the individual cells to 100% SOC at a set charging rate, pulse discharge the third part of the individual cells at a set pulse discharge rate until the set stop condition is reached. The pulse discharge rate is set based on the required battery discharge capacity. 2) Collect the battery voltage and battery temperature at the end of each pulse during the pulse discharge process, and generate a distribution map of the battery voltage and battery temperature at the end of each pulse during the pulse discharge process; 3) Based on the preset discrete requirements, filter out the individual cells corresponding to low voltage values ​​and high temperature values ​​that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at the end of each pulse during the pulse discharge process, and obtain the fourth part of individual cells.

[0058] Optionally, the pulse discharge rate in the third dynamic screening process is higher than the charge / discharge rate in the first / second dynamic screening process.

[0059] Specifically, since a higher pulse discharge rate is usually used to make the battery release a larger current under pulse discharge conditions, the stopping conditions include the remaining individual cells reaching the set SOC (such as the set cutoff voltage) and the remaining individual cells not meeting the set ratio in the first part of individual cells.

[0060] The dynamic processes set in steps A) and B) cover most of the conventional charging and discharging processes of the battery. However, in order to screen out batteries that can work normally under some more extreme operating conditions (such as higher pulse discharge rates) required by users, a third dynamic screening process is needed to test the discharge capacity of the third batch of individual batteries under the set operating conditions (such as the set pulse discharge conditions) and screen out individual batteries that do not meet the consistency requirements.

[0061] Optionally, the pulse discharge condition set above is to make the third part of the single cell perform periodic pulse discharge according to the set pulse discharge rate and the set pulse width. Specifically, it can be pulse discharge at the 3C pulse discharge rate, and the screening of single cells that do not meet the consistency requirements refers to screening out single cells whose voltage and temperature at the end of each pulse (the end of the pulse width of each pulse) do not meet the discrete requirements.

[0062] The pulse discharge condition of the third dynamic process in step C) ensures the consistency of the selected fourth batch of individual cells under the set conditions.

[0063] In one or more embodiments, the dynamic screening process in the embodiments of this application includes at least one dynamic screening process in the first / second / third dynamic screening process corresponding to the aforementioned steps A), B), and C). The dynamic screening process in the embodiments of this application is performed in a charge-discharge test device including multiple probes. The individual cells in the charge-discharge test device are connected in series through multiple probes. The probes are used to detect and control the current and voltage changes of the individual cells in the charge-discharge test device during the charge-discharge process.

[0064] Optionally, the dynamic screening process in this application embodiment includes at least one of the aforementioned first / second / third dynamic screening processes, and is performed in the order of steps A), B), and C).

[0065] It should be noted that, in order to ensure that the number of individual cells sorted out in the final process is not less than the required number of individual cells, the following rules are used to limit the number of individual cells in the battery sorting process in this embodiment of the application.

[0066] Rule 1

[0067] The number of individual cells obtained from the first batch of screening based on the static screening method is twice the number of individual cells required.

[0068] Rule Two

[0069] In the first / second / third dynamic screening process, after each screening of individual cells that do not meet the discrete requirements, if the screening ratio does not reach the set ratio, a portion of individual cells will be screened again according to the set screening conditions until the screening ratio reaches the set ratio.

[0070] Specifically, the screening ratio refers to the proportion of the number of individual cells screened out each time according to the dynamic screening conditions to the number of individual cells before the current screening was performed.

[0071] For example, the set ratio can be 2%. In step A1), if the screening ratio is less than 2%, according to rule two, a portion of the individual cells with high voltage and high temperature values ​​will be screened out to make the screening ratio reach 2%, and 98% of the individual cells will be retained to continue to step A2.

[0072] Rule 3

[0073] In the first / second / third dynamic screening process, each of the corresponding charging or discharging processes corresponds to a preset remaining ratio. If the proportion of the remaining single cells in the first part of the single cells after a certain screening is less than the preset remaining ratio corresponding to the current charging or discharging process, the current screening will not be performed and the current charging or discharging process will end.

[0074] For example, the preset remaining ratio corresponding to step A1) can be 95%. Then, according to rule three, the number of individual cells screened out in step A1) cannot exceed 5% of the number of individual cells in the first part.

[0075] For example, referring to the aforementioned embodiment, the number of screenings in step B1) is set to 5, and the preset remaining ratio corresponding to step B1) can be 75%. Then, according to rules two and three, the screening ratio of each screening in step B1) is at least 2%, and when the number of individual cells after screening cannot reach 75% of the number of individual cells in the first part, the screening is abandoned and step B2 is executed.

[0076] Based on the foregoing embodiments, it can be seen that in the embodiments of this application, the stopping condition for the screening in step B) the second dynamic screening process is that the proportion of the remaining single battery cells in the first part of the single batteries does not meet the set proportion. In step C) the third dynamic screening process, each screening not only needs to meet rules two and three, but also needs to stop screening after the remaining single batteries reach the set SOC. That is to say, the stopping condition of step C) includes the remaining single batteries reaching the set SOC and the proportion of the remaining single batteries in the first part of the single batteries not meeting the set proportion.

[0077] By applying the restrictions of rules one through three above, we can ensure that the number of individual cells sorted out in the end is not less than the number of individual cells required. The following is a specific example to illustrate the above rules one through three.

[0078] For example, if the required number of individual cells is set to 50, then the minimum number of individual cells in the first part is 100. If the minimum removal ratio is set to 2% for each removal in the first / second / third dynamic screening process, and the preset remaining ratios corresponding to steps A1), A2), B1), B2), and C) are 95%, 90%, 75%, 60%, and 50%, then according to the above rules one to three, the minimum number of individual cells finally sorted is 50.

[0079] Based on the battery sorting method provided in this application, the individual cells obtained after static sorting are then dynamically sorted. The dynamic sorting includes a first, second, and third dynamic screening process. Through the first dynamic screening process, individual cells with abnormal internal resistance and dynamic voltage at the end of the set charge / discharge time after battery activation are initially screened out. Then, through the second dynamic screening process, individual cells with voltage and temperature at the end of the set SOC state that do not meet the discrete requirements are screened out. Finally, through the third dynamic screening process, individual cells with voltage and temperature at the end of each pulse under the set pulse discharge condition that do not meet the discrete requirements are screened out. Through the above dynamic sorting process, the dynamic consistency of the individual cells after being assembled into a group can be guaranteed, and the discharge capacity of the battery pack under the required operating conditions can be guaranteed to meet the requirements.

[0080] Based on the same inventive concept, this application also provides a battery, which is composed of a single battery obtained by sorting the single battery to be sorted by the method described in the foregoing embodiments. The specific implementation can be referred to the foregoing embodiments, and this application will not describe it in detail.

[0081] Based on the same inventive concept, this application also provides a battery sorting device 600, such as... Figure 6 As shown, it includes at least one processor 602; and a memory 601 communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the battery sorting method described above.

[0082] Memory 601 is used to store programs. Specifically, the program may include program code, which includes computer operation instructions. Memory 601 may be volatile memory, such as random-access memory (RAM); it may also be non-volatile memory, such as flash memory, hard disk drive (HDD), or solid-state drive (SSD); or it may be any one or a combination of the above-mentioned volatile and non-volatile memory types.

[0083] Processor 602 can be a central processing unit (CPU), a network processor (NP), or a combination of a CPU and an NP. It can also be a hardware chip. The aforementioned hardware chip can be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The aforementioned PLD can be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof.

[0084] Based on the same inventive concept, embodiments of this application provide a computer program medium, wherein the computer storage medium stores a computer program, the computer program being used to enable a computer to execute the above-described battery sorting method.

[0085] The aforementioned storage medium may be a non-transitory computer-readable storage medium, such as a ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device.

[0086] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product.

[0087] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a server or data center that integrates one or more available media. The available medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid-state disk (SSD)).

[0088] The technical solutions provided in this application have been described in detail above. Specific examples have been used in this application to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

[0089] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0090] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should be understood by those skilled in the art from the computer program instructions that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of one or more computer-usable storage media containing computer-usable program code (implementing each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams). These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0091] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0092] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0093] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for sorting batteries, characterized in that, include: Collect static sorting parameters of the individual cells to be sorted, and select the first batch of individual cells based on the pre-defined static sorting criteria; Discharge the first batch of individual cells to the set cutoff voltage; Based on the set dynamic screening process and corresponding dynamic screening conditions, individual cells in the first part of the individual cells whose voltage and temperature do not meet the dynamic screening conditions during the set dynamic screening process are screened out. The process of filtering out individual cells in the first batch of cells whose voltage and temperature do not meet the dynamic screening conditions during the set dynamic screening process, based on the set dynamic screening process and corresponding dynamic screening conditions, includes the following steps: Through the first dynamic screening process, individual cells in the first part of the individual cells whose voltage and temperature do not meet the discrete requirements at the end of the set charge and discharge time are screened out, and the second part of the individual cells are obtained. Discharge the obtained second portion of the individual cells to the set cutoff voltage; Through the second dynamic screening process, individual cells in the second part of the individual cells whose voltage and temperature at the set state of charge (SOC) end do not meet the discrete requirements are screened out, and the third part of the individual cells are obtained. The second dynamic screening process includes: screening out voltage and temperature dispersion at multiple preset SOC nodes during the charging process from 0% SOC to 100% SOC, and at multiple preset SOC nodes during the discharging process from 100% SOC to 0% SOC. Fully charge the third portion of the individual cells obtained; Through the third dynamic screening process, individual cells in the third part of the individual cells that do not meet the discrete requirements at the end of each pulse under the set pulse discharge conditions are screened out, and the fourth part of the individual cells are obtained. In the third dynamic screening process, the pulse discharge rate is higher than the charge / discharge rate in the first / second dynamic screening processes.

2. The method according to claim 1, characterized in that, The static sorting parameters include capacity, internal resistance, open-circuit voltage, and self-discharge rate. The static sorting criteria include the set ranges for capacity difference, internal resistance difference, voltage difference, and self-discharge rate.

3. The method according to claim 1, characterized in that, The dynamic screening process is carried out in a charge-discharge test device that includes multiple probes. The individual cells in the charge-discharge test device are connected in series through multiple probes. The probes are used to detect and control the changes in current and voltage of the individual cells in the charge-discharge test device during the charge-discharge process.

4. The method according to claim 1, characterized in that, The dynamic screening process is a charging / discharging process at a set charging / discharging rate. The dynamic screening conditions include high temperature values ​​that do not meet the discrete requirements during the set dynamic screening process, high voltage values ​​that do not meet the discrete requirements during the charging process, and low voltage values ​​that do not meet the discrete requirements during the discharging process.

5. The method according to claim 1, characterized in that, The first dynamic filtering process is as follows: The first batch of individual batteries are charged to a set charging time at a set charging rate, and the battery voltage and battery temperature at the end of the set charging time are collected to generate a distribution map of battery voltage and battery temperature at the end of the charging time. Based on the preset discrete requirements, individual cells that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at the charging end are screened out, resulting in the first batch of individual cells after preliminary screening. The first batch of individual cells after preliminary screening are discharged at a set discharge rate for a set discharge duration, and the battery voltage and battery temperature at the end of the set discharge duration are collected to generate a distribution map of battery voltage and battery temperature at the end of the discharge. Based on the preset discrete requirements, individual cells that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at the discharge end are screened out, resulting in the second batch of individual cells.

6. The method according to claim 1, characterized in that, The second dynamic filtering process is as follows: The second part of the single cells is charged from 0% SOC to 100% SOC at a set charging rate, and the battery voltage and battery temperature at different SOC ends are collected during the charging process to generate a distribution map of battery voltage and battery temperature at different SOC ends during the charging process. Based on the preset discrete requirements, individual cells that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at different SOC ends during the charging process are screened out, and the screening is stopped after the set stopping condition is reached, resulting in the second part of individual cells after preliminary screening. The second batch of individual cells after preliminary screening are discharged from 100% SOC to 0% SOC at a set discharge rate, and the battery voltage and battery temperature at different SOC ends during the discharge process are collected to generate a distribution map of battery voltage and battery temperature at different SOC ends during the discharge process. Based on preset discrete requirements, individual cells that do not meet the discrete requirements in the distribution map of battery voltage and battery temperature at different SOC ends during the discharge process are screened out, and the screening stops after the set stopping condition is reached, thus obtaining the third part of individual cells.

7. The method according to claim 1, characterized in that, The third dynamic filtering process is as follows: After charging the third group of individual cells to 100% SOC at a set charging rate, pulse discharge is performed on the third group of individual cells at a set pulse discharge rate until a set stop condition is reached. The pulse discharge rate is set based on the required battery discharge capacity. The battery voltage and temperature at the end of each pulse during the pulse discharge process are collected, and a distribution map of the battery voltage and temperature at the end of each pulse during the pulse discharge process is generated. Based on the preset discrete requirements, the individual cells corresponding to low voltage values ​​and high temperature values ​​that do not meet the discrete requirements on the distribution map of battery voltage and battery temperature at the end of each pulse during the pulse discharge process are screened out, resulting in the fourth part of individual cells.

8. The method according to claim 6 or 7, characterized in that, The stopping condition includes at least one of the following: The remaining individual cells have reached the set SOC; The proportion of the remaining individual cells in the first batch of individual cells does not meet the set ratio.

9. The method according to any one of claims 1-7, characterized in that, The pulse discharge rate in the third dynamic screening process is higher than the charge / discharge rate in the first / second dynamic screening processes.

10. The method according to any one of claims 1-7, characterized in that, In the first / second / third dynamic screening process, after each screening of individual cells that do not meet the discrete requirements, if the screening ratio does not reach the set ratio, a portion of individual cells will be screened again according to the set screening conditions until the screening ratio reaches the set ratio. In the first / second / third dynamic screening process, each of the corresponding charging or discharging processes corresponds to a preset remaining ratio. If the proportion of the remaining single cells in the first part of the single cells after a certain screening is less than the preset remaining ratio corresponding to the current charging or discharging process, the current screening will not be performed and the current charging or discharging process will end.

11. The method according to claim 1, characterized in that, The number of individual cells in the first part is twice the number of individual cells required.

12. A battery, characterized in that, The single cell structure obtained by the method according to any one of claims 1-11.

13. A battery sorting device, characterized in that, The method includes at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method as described in any one of claims 1-11.

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