Battery equalization time determination method, storage medium, and electronic device

Abstract

The present disclosure relates to a battery equalization time determination method, a storage medium and an electronic device, to solve the problems of low applicability of equalization time calculation algorithm and low accuracy of obtained equalization time in the related art, comprising: in response to the battery charging stopping, determining whether the current charging satisfies the effective charging condition; in the case that the current charging satisfies the effective charging condition, taking the lowest voltage of the single battery in the battery pack at the time of charging stopping as the reference voltage; querying the first equalization capacity of the other single batteries in the battery pack except the single battery corresponding to the reference voltage at the time of charging to the target voltage, the target voltage being determined according to the reference voltage; determining the equalization time of each other single battery according to the first equalization capacity corresponding to the other single batteries, the preset equalization current and the second equalization capacity corresponding to the reference voltage. The algorithm applicability and equalization time accuracy are improved.

Description

Technical Field

[0001] This disclosure relates to the field of battery technology, and more specifically, to a method for determining battery equalization time, a storage medium, and an electronic device. Background Technology

[0002] To address the issue of inconsistent battery capacities among individual cells in a battery pack, power balancing can typically be achieved by transferring power from larger capacity cells to smaller capacity cells, or by releasing power from larger capacity cells at the end of the charging process.

[0003] For battery equalization, equalization time is a crucial indicator. Typically, the average voltage of each individual cell during charging is calculated when the battery is fully charged. The voltage change curve of the cell with the lowest average voltage is used as a reference voltage curve. The shift time is obtained by comparing the voltage change curves of other individual cells. The product of the shift time and the charging current is then used to calculate the capacity difference between the individual cells, thus yielding the equalization time. However, calculating only when the battery is fully charged is inadequate for batteries used in shared and swapping systems, where batteries are typically deployed at 85%-90% charge, preventing them from reaching full charge. This results in limited applicability. Furthermore, current fluctuations during charging often lead to inaccurate capacity difference calculations, resulting in inaccurate equalization times. Summary of the Invention

[0004] The purpose of this disclosure is to provide a method, storage medium, and electronic device for determining battery equalization time, in order to solve the problems of low applicability and low accuracy of equalization time calculation algorithms in related technologies.

[0005] To achieve the above objectives, the first aspect of this disclosure provides a method for determining battery balancing time, comprising:

[0006] In response to the battery charging stopping, determine whether the current charging meets the valid charging conditions;

[0007] If the current charging meets the effective charging conditions, the lowest voltage of a single cell in the battery pack when the charging stops is used as the reference voltage.

[0008] The first equalization capacity of each individual cell in the battery pack, excluding the cell corresponding to the reference voltage, is queried at the moment when it is charged to the target voltage, wherein the target voltage is determined based on the reference voltage;

[0009] The equalization time for each of the other individual cells is determined based on the first equalization capacity corresponding to the other individual cells, the preset equalization current, and the second equalization capacity corresponding to the reference voltage.

[0010] Optionally, determining the target voltage includes:

[0011] Based on the charging time sequence, starting from the moment the charging stops, the charging voltage of other individual cells in the battery pack, excluding the individual cell corresponding to the reference voltage, is retrieved in reverse order until the first charging voltage of that other individual cell that is less than or equal to the reference voltage is found.

[0012] The first charging voltage, which is less than or equal to the reference voltage, is taken as the target voltage for the other individual cells.

[0013] Optionally, querying the first equalization capacity of other individual cells in the battery pack, excluding the cell corresponding to the reference voltage, at the time of charging to the target voltage includes:

[0014] Determine the target time when the other individual cells are charged to the corresponding target voltage;

[0015] Determine the charging voltage of the other individual battery cells within a preset range of the target time;

[0016] Based on the charging voltage within a preset range corresponding to the target time for the other individual cells and the target voltage, determine whether the target voltage corresponding to each of the other individual cells is a jump voltage;

[0017] If the target voltage corresponding to the other single cell is not a jump voltage, the battery capacity at the target time corresponding to the other single cell is taken as the corresponding first equalization capacity.

[0018] Optionally, the method includes:

[0019] If the target voltage corresponding to the other individual cell is a jump voltage, repeat the following steps:

[0020] Starting from the charging time corresponding to the jump voltage, continue to look up the charging voltage of other individual cells in reverse until the next charging voltage of other individual cells that is less than or equal to the reference voltage is found, and a new target voltage is obtained.

[0021] Determine whether the new target voltage of the other single cell is a jump voltage. Until the target voltage corresponding to the other single cell is not a jump voltage, the battery capacity at the target time corresponding to the other single cell is taken as the corresponding first equalization capacity.

[0022] Optionally, determining whether the target voltage corresponding to each of the other individual cells is a jump voltage based on the charging voltage within a preset range at the target time and the target voltage for each of the other individual cells includes:

[0023] Calculate the voltage difference between the charging voltage and the target voltage at each of the other individual battery cells within a preset range of the target time.

[0024] Based on the voltage difference corresponding to each of the other individual cells and a preset voltage difference threshold, it is determined whether the target voltage corresponding to each of the other individual cells is a jump voltage.

[0025] Optionally, the charging time within the preset range is the charging time adjacent to the target time.

[0026] Optionally, the effective charging conditions include:

[0027] When charging stops, the difference between the highest and lowest individual cell voltages in the battery pack is greater than a preset voltage threshold, and the amount of charge generated during the current charge is greater than a preset charge threshold. Furthermore, when charging stops, the highest individual cell voltage in the battery pack is greater than or equal to the equalization voltage, which is determined based on the battery's voltage plateau.

[0028] Optionally, the battery charging stop includes at least one of the following: the battery charger is disconnected from the charging equipment, or the charging current rate during the charging process is less than or equal to a preset current rate threshold.

[0029] A second aspect of this disclosure provides a battery equalization time determination apparatus, comprising:

[0030] The first determining module is configured to determine whether the current charging meets the valid charging conditions in response to the battery charging stopping.

[0031] The reference voltage determination module is configured to take the lowest voltage of a single cell in the battery pack when the charging stops, provided that the current charging meets the valid charging conditions.

[0032] The query module is configured to query the first equalization capacity of other individual cells in the battery pack, excluding the individual cells corresponding to the reference voltage, at the time when they are charged to the target voltage, wherein the target voltage is determined based on the reference voltage;

[0033] The second determining module is configured to determine the equalization time of each of the other individual cells based on the first equalization capacity corresponding to the other individual cells, the preset equalization current, and the second equalization capacity corresponding to the reference voltage.

[0034] Optionally, the query module includes:

[0035] The query submodule is configured to, based on the time sequence of the current charging, and starting from the time when the charging stops, reverse the query to find the charging voltage of other individual cells in the battery pack, excluding the individual cell corresponding to the reference voltage, until the first charging voltage of that other individual cell that is less than or equal to the reference voltage is found.

[0036] The first determining submodule is configured to use the first charging voltage, which is less than or equal to the reference voltage, as the target voltage for the other individual cells.

[0037] Optionally, the query module includes:

[0038] The first acquisition submodule is configured to acquire the target time when each of the other individual cells is charged to the corresponding target voltage;

[0039] The second acquisition submodule is configured to acquire the charging voltage of each of the other individual batteries within a preset range of the target time.

[0040] The second determining submodule is configured to determine whether the target voltage corresponding to each of the other individual cells is a jump voltage based on the charging voltage within a preset range at the target time corresponding to each of the other individual cells and the target voltage.

[0041] The third determining submodule is configured to, when the target voltage corresponding to the other single cell is not a jump voltage, take the battery capacity at the target time corresponding to the other single cell as the corresponding first equalization capacity.

[0042] Optionally, the query module is configured to repeatedly execute the following steps when the target voltage corresponding to the other individual battery cell is a jump voltage:

[0043] Starting from the charging time corresponding to the jump voltage, continue to look up the charging voltage of other individual cells in reverse until the next charging voltage of other individual cells that is less than or equal to the reference voltage is found, and a new target voltage is obtained.

[0044] Determine whether the new target voltage of the other single cell is a jump voltage. Until the target voltage corresponding to the other single cell is not a jump voltage, the battery capacity at the target time corresponding to the other single cell is taken as the corresponding first equalization capacity.

[0045] Optionally, the second determining submodule is configured as follows:

[0046] Calculate the voltage difference between the charging voltage and the target voltage at each of the other individual battery cells within a preset range of the target time.

[0047] Based on the voltage difference corresponding to each of the other individual cells and a preset voltage difference threshold, it is determined whether the target voltage corresponding to each of the other individual cells is a jump voltage.

[0048] Optionally, the charging time within the preset range is the charging time adjacent to the target time.

[0049] Optionally, the effective charging conditions include:

[0050] When charging stops, the difference between the highest and lowest individual cell voltages in the battery pack is greater than a preset voltage threshold, and the amount of charge generated during the current charge is greater than a preset charge threshold. Furthermore, when charging stops, the highest individual cell voltage in the battery pack is greater than or equal to the equalization voltage, which is determined based on the battery's voltage plateau.

[0051] Optionally, the battery charging stop includes at least one of the following: the battery charger is disconnected from the charging equipment, or the charging current rate during the charging process is less than or equal to a preset current rate threshold.

[0052] A third aspect of this disclosure provides a computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the steps of the method described in any of the first aspects.

[0053] A fourth aspect of this disclosure provides an electronic device, comprising:

[0054] A memory on which computer programs are stored;

[0055] A processor for executing the computer program in the memory to implement the steps of the method of any one of the first aspects.

[0056] The above technical solution can achieve at least the following technical effects:

[0057] By responding to the cessation of battery charging, it determines whether the current charging meets the valid charging conditions. If the current charging meets the valid charging conditions, the lowest voltage of a single cell in the battery pack at the time of charging cessation is used as the reference voltage. The first equalization capacity corresponding to the other single cells in the battery pack (excluding the single cell corresponding to the reference voltage) is queried at the time of charging to the target voltage, which is determined based on the reference voltage. Based on the first equalization capacity corresponding to the other single cells, the preset equalization current, and the second equalization capacity corresponding to the reference voltage, the equalization time of each single cell is determined. This improves the applicability of the algorithm and the accuracy of the equalization time.

[0058] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0059] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0060] Figure 1 This is a flowchart of a battery balancing time determination method according to one embodiment of the present disclosure.

[0061] Figure 2 This is a schematic diagram of battery stepped charging according to one embodiment of the present disclosure.

[0062] Figure 3 This is a schematic diagram of battery capacity and charging time according to one embodiment of the present disclosure.

[0063] Figure 4 This is a flowchart of a target voltage determination method according to one embodiment of the present disclosure.

[0064] Figure 5 This is an implementation illustrated according to an exemplary embodiment. Figure 1 The flowchart for step S13.

[0065] Figure 6 This is a flowchart of a battery balancing time determination method according to another embodiment of the present disclosure.

[0066] Figure 7 This is a schematic diagram illustrating the discharge end voltage curves before and after battery capacity equalization, according to an exemplary embodiment.

[0067] Figure 8 This is a block diagram illustrating a battery balancing time determination device according to an exemplary embodiment. Detailed Implementation

[0068] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0069] In related technologies, the shift time is obtained by calculating the cosine similarity between the reference voltage curve and the voltage change curves of other individual cells. However, to improve battery protection, batteries are typically charged with stepped currents. When the charging current rate changes, the voltage curve no longer rises monotonically but exhibits significant fluctuations, making it difficult to obtain an accurate shift time using cosine similarity, thus resulting in low accuracy of the equalization time. Furthermore, the capacity difference of individual cells is obtained by multiplying the shift time (e.g., 10 seconds or 30 seconds) and the charging current, rather than through real-time integration. If current fluctuations occur during charging, the calculated capacity difference will differ from the actual capacity. A large capacity deviation is detrimental to battery equalization and increases the capacity difference between individual cells.

[0070] In view of this, this disclosure provides a method for determining battery balancing time, which can be applied to a battery management system, a vehicle controller, or an independent processing device. This disclosure uses the application to a battery management system as an example for illustration, aiming to expand the adaptability of balancing time calculation and improve the accuracy of balancing time, thereby facilitating battery charge balancing.

[0071] It can be noted that the multiple individual cells in the battery pack in this disclosure are connected in series, that is, except for the first and last individual cells in the battery pack, the positive terminal of the other individual cells is connected to the negative terminal of one individual cell, and the negative terminal of the other individual cells is connected to the positive terminal of another individual cell. Figure 1 This is a flowchart of a battery balancing time determination method according to one embodiment of the present disclosure, see [link to flowchart]. Figure 1 As shown, the method includes the following steps.

[0072] In step S11, in response to the battery charging stopping, it is determined whether the current charging meets the valid charging conditions.

[0073] During battery charging, the voltage and capacity of each individual cell in the battery pack are recorded at preset time intervals. For example, during charging, the voltage and capacity of each individual cell are recorded at 1-second intervals. When charging stops, the battery management system can fully acquire the voltage and capacity of each individual cell during the charging process.

[0074] Understandably, the preset time interval is related to the storage capacity, storage speed, task execution cycle, and capacity difference accuracy of the battery management system's built-in chip, and the preset time interval can optionally be 1 second, 3 seconds, or 5 seconds.

[0075] In this embodiment of the disclosure, stopping the battery pack charging includes at least one of the following: the charger of the battery pack is disconnected from the charging equipment, or the charging current rate during the charging process is less than or equal to a preset current rate threshold.

[0076] For example, disconnecting the battery pack's charger from the charging equipment can be done manually by unplugging the charging gun, or it can be done when the battery pack reaches full charge and the battery management system controls the charger to disconnect from the charging equipment.

[0077] Generally speaking, such as Figure 2 As shown, during the stepped charging process, the voltage of the battery pack will drop as the charging current rate decreases step by step. If the individual cells are consistent, the time to reach the same voltage at each charging moment should be relatively consistent. However, due to factors such as battery materials, manufacturing processes, capacity grading, and self-discharge characteristics, there are differences in reaching the same voltage. Therefore, in this embodiment, the charging current rate during the charging process is less than or equal to a preset current rate threshold. For example, if the charging current rate is less than 0.1C and lasts for 5 seconds, then the charging of the battery pack is determined to be stopped for this period.

[0078] In this embodiment of the disclosure, the effective charging conditions include:

[0079] When charging stops, the difference between the highest and lowest individual cell voltages in the battery pack is greater than a preset voltage threshold, and the amount of charge generated during the current charge is greater than a preset charge threshold. Furthermore, when charging stops, the highest individual cell voltage in the battery pack is greater than or equal to the equalization voltage, which is determined based on the battery's voltage plateau.

[0080] Understandably, if it is determined that the current charging meets the valid charging conditions, the subsequent equalization time will be calculated; if it is determined that the current charging does not meet the valid charging conditions, the subsequent equalization time will not be calculated.

[0081] The equalization voltage is determined based on the battery material, capacity, and charging current rate, and is greater than the voltage plateau. For example, taking a lithium iron phosphate battery as an example, the voltage plateau of a lithium iron phosphate battery is 3.2V, so the equalization voltage of a lithium iron phosphate battery can be determined to be 3.45V.

[0082] To prevent repeated triggering of equalization time calculation, a preset power threshold can be determined based on the battery material, capacity, and charging current rate. Taking lithium iron phosphate battery as an example, the preset power threshold is 0.1C.

[0083] Similarly, the preset voltage threshold is determined based on the battery material, capacity, and charging current rate. Taking lithium iron phosphate battery as an example, the preset voltage threshold is 40mV.

[0084] In step S12, if the current charging meets the valid charging conditions, the lowest voltage of a single cell in the battery pack when charging stops is used as the reference voltage.

[0085] For example, taking a battery pack containing two individual battery cells, where the voltage of the first individual cell is 3511mV and the voltage of the second individual cell is 3493mV, the voltage of the second individual cell, 3493mV, is used as the reference voltage.

[0086] In step S13, the first equalization capacity of other individual cells in the battery pack, excluding the individual cell corresponding to the reference voltage, is queried when they are charged to the target voltage. The target voltage is determined based on the reference voltage.

[0087] In this embodiment of the disclosure, the target voltage is the voltage within a preset difference from the reference voltage. For example, the preset difference can be 2mV. Therefore, the target voltage for each individual cell other than the one corresponding to the reference voltage is the first voltage within the range of 3493mV ± 2mV. See also... Figure 3 As shown, the voltage of 3495mV at 02:47:18 can be found to be the target voltage of the first single cell.

[0088] In step S14, the equalization time of each individual cell is determined based on the first equalization capacity corresponding to other individual cells, the preset equalization current, and the second equalization capacity corresponding to the reference voltage.

[0089] In this embodiment, the battery capacity stored each time can be the total battery capacity, the capacity of the lowest-capacity individual cell, or the capacity of the highest-capacity individual cell, as long as the stored data uses the same standard. This ensures that the first equalization capacity and the second equalization capacity are based on the same standard.

[0090] Continue Figure 3 To clarify, when charging stops at 02:47:33, the total battery capacity is determined to be 21.193Ah. Therefore, the second equalization capacity is 21.193Ah. At this time, the voltage of the lowest voltage Cell3 cell is 3482mV. The time when Cell1 cell reached 3482mV is found to be 02:46:59, at which point the total battery capacity is 21.121Ah. Therefore, the first equalization capacity of Cell1 cell is 21.121Ah. Similarly, the time when Cell2 cell reached 3482mV is found to be 02:47:15, at which point the total battery capacity is 21.155Ah. Therefore, the first equalization capacity of Cell2 cell is 21.155Ah.

[0091] Furthermore, the capacity difference between the first and second equalization capacities corresponding to each individual cell is calculated. The quotient of each capacity difference and the equalization current is then calculated to obtain the equalization time for each individual cell. That is, the equalization time for each individual cell is Tn = (C - Cn) / I, where I is the equalization current, C is the second equalization capacity, and Cn is the first equalization capacity for each individual cell.

[0092] Following the above embodiment, the capacity difference between the second equalization capacity and the first equalization capacity of Cell1 single cell is C-C1 = 21.193 - 21.121 = 0.072 Ah, and the capacity difference between the second equalization capacity and the first equalization capacity of Cell2 single cell is C-C2 = 21.193 - 21.155 = 0.038 Ah. If the equalization current I = 0.1A, then the equalization time for Cell1 single cell is T1 = 0.72 hours, and the equalization time for Cell2 single cell is T2 = 0.38 hours.

[0093] In this embodiment of the disclosure, after charging stops, when it is determined that the balancing time is non-zero and the balancing start condition is met, balancing of individual cells in the battery pack begins. The balancing priority is sorted according to the balancing time; the longer the balancing time required, the higher the balancing priority, until the balancing time of each cell is 0. When a valid charging process occurs again, the balancing time is calculated again, and so on, to ensure the consistency of battery capacity.

[0094] For example, when a battery pack includes four individual battery strings, if the balancing time for individual battery #1 is 1 hour, the balancing time for individual battery #2 is 0.5 hours, and the balancing time for individual battery #3 is 0.1 hours, then individual battery #1 has the highest balancing time, and individual battery #3 has the lowest balancing time. Therefore, individual battery #1 should be balanced first, then individual battery #2 should be balanced, and finally individual battery #3 should be balanced.

[0095] In one implementation, when the battery management system experiences a communication failure with the voltage acquisition module or a cell voltage sampling line disconnection protection, the equalization time is not calculated because the stored voltage data may be distorted.

[0096] In one embodiment, the battery management system includes a data acquisition module for acquiring the voltage and capacity of individual cells; a storage module for storing the voltage and capacity of each individual cell at preset time intervals; a data processing module for retrieving the stored voltage and capacity, calculating the capacity difference that each individual cell needs to balance, and then calculating the balancing time of each cell using the balancing current; and a balancing module for performing power balancing on individual cells during charging, discharging, and resting processes based on the balancing time and battery status of each individual cell, and performing balancing start judgment, balancing suspension judgment, single cell balancing stop judgment, and whole pack balancing stop judgment to ensure that the battery performs power balancing in a safe and reliable state.

[0097] The above technical solution determines whether the current charging meets the valid charging conditions in response to the cessation of battery charging. If the charging meets the valid conditions, the lowest voltage of a single cell in the battery pack at the time of charging cessation is used as the reference voltage. The first equalization capacity of other cells in the battery pack, excluding the cell corresponding to the reference voltage, is queried at the time of charging to the target voltage, which is determined based on the reference voltage. The equalization time of each cell is determined based on the first equalization capacity of other cells, the preset equalization current, and the second equalization capacity corresponding to the reference voltage. The effects of charge / discharge rate, temperature field distribution differences, and cell material consistency can be ignored, improving the applicability of the algorithm and the accuracy of the equalization time.

[0098] Based on the above embodiments, this disclosure provides a method for determining a target voltage, see [link to relevant documentation]. Figure 4 As shown, the method includes the following steps.

[0099] In step S41, based on the time sequence of this charging, starting from the moment the charging stops, the charging voltage of other individual cells in the battery pack, excluding the individual cell corresponding to the reference voltage, is queried in reverse until the first charging voltage of that other individual cell that is less than or equal to the reference voltage is found.

[0100] by Figure 3 Taking 02:47:33, the time when charging stopped, as the starting point, the voltage of the first individual battery is looked up in reverse. The voltage at 02:47:32 is found to be 3510mV. The reverse lookup continues until the voltage at 02:47:14 is found to be 3493mV. The voltage at 02:47:14 is the first charging voltage equal to the reference voltage, so the reverse lookup stops.

[0101] In step S42, the first charging voltage that is less than or equal to the reference voltage is taken as the target voltage for the other individual cells.

[0102] The first charging voltage less than or equal to the reference voltage can be interpreted as the charging voltage at the charging moment closest to the target time that is less than or equal to the reference voltage.

[0103] exist Figure 4 Based on the embodiments, see Figure 5 As shown, in step S13, querying the first equalization capacity of other individual cells in the battery pack, excluding the individual cell corresponding to the reference voltage, at the time of charging to the target voltage includes the following steps.

[0104] In step S131, the target time when other individual cells are charged to the corresponding target voltage is determined.

[0105] Taking a battery pack containing four individual cells as an example, we determine the first target time when cell #1 is charged to the target voltage; the second target time when cell #2 is charged to the target voltage; and the third target time when cell #3 is charged to the target voltage.

[0106] In step S132, the charging voltage of the other individual cells is determined within a preset range of the target time.

[0107] Optionally, the preset range can be a preset time range or a preset number range. For example, it can be the charging voltage of each individual battery within 2 seconds before and after the target time, or it can be the charging voltage of each individual battery at three recorded charging times before and after the target time.

[0108] In step S133, based on the charging voltage and target voltage within the preset range of the target time corresponding to the other individual cells, it is determined whether the target voltage corresponding to each other individual cell is a jump voltage.

[0109] In this embodiment, determining whether the target voltage corresponding to each of the other individual cells is a jump voltage based on the charging voltage within a preset range at the target time and the target voltage for each of the other individual cells includes:

[0110] Calculate the voltage difference between the charging voltage and the target voltage at each of the other individual battery cells within a preset range of the target time.

[0111] Based on the voltage difference corresponding to each of the other individual cells and a preset voltage difference threshold, it is determined whether the target voltage corresponding to each of the other individual cells is a jump voltage.

[0112] It is understandable that if the voltage difference corresponding to a single cell is greater than or equal to a preset voltage difference threshold, the target voltage corresponding to that single cell is determined to be a jump voltage; if the voltage difference corresponding to a single cell is less than the preset voltage difference threshold, the target voltage corresponding to that single cell is determined not to be a jump voltage.

[0113] In step S134, if the target voltage corresponding to the other single cell is not a jump voltage, the battery capacity at the target time corresponding to the other single cell is taken as the corresponding first equalization capacity.

[0114] See Figure 3 As shown, if the target voltage of the first single cell at 02:47:14 is determined to be 3493mV and is not a jump voltage, the battery capacity of 21.153 at 02:47:14 is taken as the first equalization capacity of the first single cell.

[0115] Based on the above embodiments, the method includes:

[0116] If the target voltage corresponding to the other individual cell is a jump voltage, repeat the following steps:

[0117] Starting from the charging time corresponding to the jump voltage, continue to look up the charging voltage of other individual cells in reverse until the next charging voltage of other individual cells that is less than or equal to the reference voltage is found, and a new target voltage is obtained.

[0118] For example, if the target voltage of the first single cell at 02:47:14 is determined to be 3493mV, which is the jump voltage, the charging voltage of the first single cell is continuously queried in reverse from 02:47:14 until the next charging voltage less than or equal to the reference voltage is found, and a new target voltage is obtained.

[0119] Determine whether the new target voltage of the other single cell is a jump voltage. Until the target voltage corresponding to the other single cell is not a jump voltage, the battery capacity at the target time corresponding to the other single cell is taken as the corresponding first equalization capacity.

[0120] Understandable, it can be done Figure 5 The method shown determines whether the new target voltage of the other single cell is a jump voltage.

[0121] Based on the above embodiments, the charging time within the preset range is the adjacent charging time of the target time.

[0122] For example, if the voltage at 02:47:14 is 3493mV, then the adjacent charging times for the target time are 02:47:13 and 02:47:15. The voltage difference between the charging voltage at 02:47:13 and the target voltage, and the voltage difference between the charging voltage at 02:47:15 and the target voltage, are then calculated. If the calculated voltage differences are both less than a preset voltage difference threshold, then the target voltage is determined not to be a jump voltage. If any voltage difference is greater than or equal to the preset voltage difference threshold, then the target voltage for that single battery cell is determined to be a jump voltage.

[0123] The algorithm disclosed herein does not have any characteristic requirements for individual cells in the battery pack, thus the effects of charge / discharge rate, temperature field distribution differences, and cell material consistency can be ignored. Even if the capacity difference is large or the characteristics of individual cells are different, as long as they are in the same voltage system, it can be applied. If they are not in the same voltage system but have the same charging cut-off voltage, the algorithm disclosed herein can also be used to calculate the equalization time, thus improving the applicability of the algorithm and the accuracy of the equalization time.

[0124] Furthermore, the technical solution adopted in this disclosure obtains the balancing time through data retrieval and capacity calculation, which simplifies the calculation difficulty of the balancing time, thereby reducing the requirements for hardware computing power. It eliminates the need for cloud-assisted calculation, reduces data transmission back and forth, and improves calculation speed while avoiding data loss caused by back-and-forth data transmission. Moreover, this technical solution does not require complex data fitting calculations, consumes less hardware data, and has lower requirements. It can be applied to battery management systems, vehicle controllers, or independent processing devices, covering more usage scenarios. Even when using a stepped charging current or under conditions of incomplete charging, calculations can be performed as long as the stopping condition is met. It is also applicable to products with limited computing power, effectively ensuring the safety of the battery pack. In addition, the capacity scale uses a coulomb counter to determine the battery capacity in real time through integration, accurately calculating the capacity difference and balancing time, improving the accuracy of battery balancing, avoiding over- or under-balancing, ensuring battery pack consistency, and extending battery pack lifespan.

[0125] The battery balancing time determination method of this disclosure is illustrated below through a specific embodiment. (See also...) Figure 6 As shown, in step S61, the charging data of each individual battery cell is periodically recorded and stored. The charging data includes the charging voltage and the battery capacity.

[0126] In step S62, it is determined whether the current charging has stopped. If it is determined that the current charging has not stopped, the process ends and continues to step S61. If it is determined that the current charging has stopped, step S63 is executed.

[0127] In step S63, it is determined whether the current charging process is a valid charging process. That is, whether the current charging meets the valid charging conditions. If it is determined that the current charging is not a valid charging process, the process ends and continues to step S61. If it is determined that the current charging is a valid charging process, step S64 is executed.

[0128] In step S64, the lowest voltage V of the single cell in this charge is obtained. min And the corresponding battery capacity C.

[0129] In step S65, the other individual cells are queried when they are charged to the lowest voltage V. min The first equalization capacity C at time t = ... n .

[0130] In step S66, the first equalization capacity C is calculated. n The difference in capacity between the battery capacity C and the capacity C.

[0131] In step S67, the quotient of each capacity difference and the preset equalization current is calculated to obtain the equalization time.

[0132] In step S68, the equalization time is updated.

[0133] See Figure 7 As shown, the discharge end voltage curve is the result of battery capacity balancing according to an embodiment of this disclosure. Before the capacity of the higher-capacity individual cells is balanced, the voltage of the higher-capacity individual cells is much higher than that of the lower-capacity individual cells. After the capacity of the higher-capacity individual cells is balanced, the discharge end voltages of the individual cells tend to be consistent.

[0134] Based on the same concept, this disclosure also provides a battery balancing time determination device for performing the steps of the battery balancing time determination method provided in the above embodiments. The device can implement the battery balancing time determination method in software, hardware, or a combination of both. Figure 8 This is a block diagram illustrating a battery balancing time determination device 800 according to an exemplary embodiment, such as... Figure 8 As shown, the device 800 includes: a first determining module 810, a reference voltage determining module 820, a query module 830, and a second determining module 840.

[0135] The first determining module 810 is configured to determine whether the current charging meets the valid charging conditions in response to the battery charging stopping.

[0136] The reference voltage determination module 820 is configured to use the lowest voltage of a single cell in the battery pack when the charging stops, provided that the current charging meets the valid charging conditions.

[0137] The query module 830 is configured to query the first equalization capacity of other individual cells in the battery pack, excluding the individual cell corresponding to the reference voltage, at the time of charging to the target voltage, wherein the target voltage is determined based on the reference voltage;

[0138] The second determining module 840 is configured to determine the equalization time of each of the other individual cells based on the first equalization capacity corresponding to the other individual cells, the preset equalization current, and the second equalization capacity corresponding to the reference voltage.

[0139] Optionally, the query module 830 includes:

[0140] The query submodule is configured to, based on the time sequence of the current charging, and starting from the time when the charging stops, reverse the query to find the charging voltage of other individual cells in the battery pack, excluding the individual cell corresponding to the reference voltage, until the first charging voltage of that other individual cell that is less than or equal to the reference voltage is found.

[0141] The first determining submodule is configured to use the first charging voltage, which is less than or equal to the reference voltage, as the target voltage for the other individual cells.

[0142] Optionally, the query module 830 includes:

[0143] The first acquisition submodule is configured to determine the target time when the other individual cells are charged to the corresponding target voltage;

[0144] The second acquisition submodule is configured to determine the charging voltage of the other individual battery cells within a preset range of the target time.

[0145] The second determining submodule is configured to determine whether the target voltage corresponding to each of the other individual cells is a jump voltage based on the charging voltage within a preset range at the target time corresponding to the other individual cells and the target voltage.

[0146] The third determining submodule is configured to, when the target voltage corresponding to the other single cell is not a jump voltage, take the battery capacity at the target time corresponding to the other single cell as the corresponding first equalization capacity.

[0147] Optionally, the query module 830 is configured to repeatedly execute the following steps when the target voltage corresponding to the other individual battery is a jump voltage:

[0148] Starting from the charging time corresponding to the jump voltage, continue to look up the charging voltage of other individual cells in reverse until the next charging voltage of other individual cells that is less than or equal to the reference voltage is found, and a new target voltage is obtained.

[0149] Determine whether the new target voltage of the other single cell is a jump voltage. Until the target voltage corresponding to the other single cell is not a jump voltage, the battery capacity at the target time corresponding to the other single cell is taken as the corresponding first equalization capacity.

[0150] Optionally, the second determining submodule is configured as follows:

[0151] Calculate the voltage difference between the charging voltage and the target voltage at each of the other individual battery cells within a preset range of the target time.

[0152] Based on the voltage difference corresponding to each of the other individual cells and a preset voltage difference threshold, it is determined whether the target voltage corresponding to each of the other individual cells is a jump voltage.

[0153] Optionally, the charging time within the preset range is the charging time adjacent to the target time.

[0154] Optionally, the effective charging conditions include:

[0155] When charging stops, the difference between the highest and lowest individual cell voltages in the battery pack is greater than a preset voltage threshold, and the amount of charge generated during the current charge is greater than a preset charge threshold. Furthermore, when charging stops, the highest individual cell voltage in the battery pack is greater than or equal to the equalization voltage, which is determined based on the battery's voltage plateau.

[0156] Optionally, the battery charging stop includes at least one of the following: the battery charger is disconnected from the charging equipment, or the charging current rate during the charging process is less than or equal to a preset current rate threshold.

[0157] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0158] Furthermore, it is worth noting that, for the sake of convenience and brevity, the embodiments described in the specification are all preferred embodiments, and the parts involved are not necessarily essential to the present invention. For example, the query module 830 and the second determination module 840 can be independent devices or the same device in specific implementations, and this disclosure does not limit them.

[0159] This disclosure provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the battery balancing time determination method described in any of the preceding claims.

[0160] This disclosure provides an electronic device, including:

[0161] A memory on which computer programs are stored;

[0162] A processor is configured to execute the computer program in the memory to implement the steps of any of the preceding battery balancing time determination methods.

[0163] In this embodiment of the disclosure, the electronic device can be configured as an independent processing device, or it can be configured as a vehicle controller or a battery management system, that is, the aforementioned battery balancing time determination method can be used as part of the functions of the vehicle controller or the battery management system.

[0164] For example, when the aforementioned battery is a battery for an electric bicycle, the electronic device can be configured as a vehicle controller; when the aforementioned battery is a battery in the field of sharing or battery swapping, the electronic device can be configured as a battery management system within a battery pack; and when the aforementioned battery is a power battery for an electric vehicle, the electronic device can be configured as a battery management system on the electric vehicle.

[0165] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0166] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0167] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A method for determining battery equalization time, characterized in that, include: In response to the cessation of battery pack charging, it is determined whether the current charging meets the effective charging conditions. The effective charging conditions include: the difference between the highest and lowest individual cell voltages in the battery pack is greater than a preset voltage threshold when charging stops, the charging amount of the current charging is greater than a preset amount threshold, and the highest individual cell voltage in the battery pack is greater than or equal to the equalization voltage when charging stops. The equalization voltage is determined based on the battery's voltage platform. If the current charging meets the effective charging conditions, the lowest voltage of a single cell in the battery pack when the charging stops is used as the reference voltage. The first equalization capacity of each individual cell in the battery pack, excluding the cell corresponding to the reference voltage, is queried at the moment when it is charged to the target voltage, wherein the target voltage is determined based on the reference voltage; The equalization time of each of the other individual cells is determined based on the first equalization capacity corresponding to the other individual cells, the preset equalization current, and the second equalization capacity corresponding to the reference voltage. The second equalization capacity is the capacity of the individual cell with the lowest voltage when charging stops. The determination of the target voltage includes: Based on the charging time sequence, starting from the moment the charging stops, the charging voltage of other individual cells in the battery pack, excluding the individual cell corresponding to the reference voltage, is retrieved in reverse order until the first charging voltage of that other individual cell that is less than or equal to the reference voltage is found. The first charging voltage, which is less than or equal to the reference voltage, is taken as the target voltage for the other individual cells.

2. The method according to claim 1, characterized in that, The querying of the first equalization capacity of other individual cells in the battery pack, excluding the cell corresponding to the reference voltage, at the time of charging to the target voltage includes: Determine the target time when the other individual cells are charged to the corresponding target voltage; Determine the charging voltage of the adjacent charging times corresponding to the target time for the other individual cells; Based on the charging voltage of the adjacent charging time corresponding to the target time of the other individual cells and the target voltage, determine whether the target voltage corresponding to each of the other individual cells is a jump voltage; If the target voltage corresponding to the other single cell is not a jump voltage, the battery capacity at the target time corresponding to the other single cell is taken as the corresponding first equalization capacity.

3. The method according to claim 2, characterized in that, The method includes: If the target voltage corresponding to the other individual cell is a jump voltage, repeat the following steps: Starting from the charging time corresponding to the jump voltage, continue to look up the charging voltage of other individual cells in reverse until the next charging voltage of other individual cells that is less than or equal to the reference voltage is found, and a new target voltage is obtained. Determine whether the new target voltage of the other single cell is a jump voltage. Until the target voltage corresponding to the other single cell is not a jump voltage, the battery capacity at the target time corresponding to the other single cell is taken as the corresponding first equalization capacity.

4. The method according to claim 2, characterized in that, The step of determining whether the target voltage corresponding to each of the other individual cells is a jump voltage based on the charging voltage of the adjacent charging time corresponding to the target time and the target voltage includes: Calculate the voltage difference between the charging voltage at adjacent charging times corresponding to the target time and the target voltage for each of the other individual cells; Based on the voltage difference corresponding to each of the other individual cells and a preset voltage difference threshold, determine whether the target voltage corresponding to each of the other individual cells is a jump voltage, including: if the voltage difference corresponding to the individual cell is greater than or equal to the preset voltage difference threshold, determine that the target voltage corresponding to the individual cell is a jump voltage; if the voltage difference corresponding to the individual cell is less than the preset voltage difference threshold, determine that the target voltage corresponding to the individual cell is not a jump voltage.

5. The method according to any one of claims 1-4, wherein the charging stop comprises: The battery pack's charger is disconnected from the charging equipment, or the charging current rate during the charging process is less than or equal to a preset current rate threshold, at least one of the following:

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method described in any one of claims 1-5.

7. An electronic device, characterized in that, include: A memory on which computer programs are stored; A processor for executing the computer program in the memory to implement the steps of the method according to any one of claims 1-5.

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