Battery management method and management device, vehicle and computer-readable storage medium

Abstract

The present application provides a battery management method, including obtaining the current high voltage inflection point power value of each single cell; obtaining the current historical cumulative balanced power value of each single cell; calculating the current equivalent self-discharge value of each single cell; obtaining the equivalent self-discharge value of each single cell at the previous moment; calculating the target equivalent self-discharge value of each single cell; determining the maximum target equivalent self-discharge value and the minimum target equivalent self-discharge value; calculating the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate; when the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, managing the target single cell corresponding to the maximum target equivalent self-discharge value. The present application also provides a battery management device, a vehicle, and a computer-readable storage medium. The battery management method of the present application can identify single cells with abnormal self-discharge by determining the target equivalent self-discharge values ​​of all batteries.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery management method and device, a vehicle, and a computer-readable storage medium. Background Art

[0002] Power batteries are widely used in the fields of electric vehicle power sources and backup power supplies. In order to increase the energy and voltage of power batteries, several single cells need to be connected in series to form a power battery pack for use. However, in the process of producing single cells, due to the production process, the self-discharge rate of each single cell is different. The difference in self-discharge rate will lead to inconsistent charge state of each single cell, making it impossible for each single cell to be fully charged to the upper limit voltage or discharged to the lower limit voltage at the same time, thereby affecting the capacity of the entire power battery pack. Therefore, it is necessary to detect the self-discharge amount of each single cell to identify the single cell with large self-discharge deviation.

[0003] Currently, self-discharge testing of single cells is performed before shipment. Specifically, the self-discharge rate of each cell is tested before shipment, and cells with roughly the same self-discharge rate are assembled into a power battery pack. However, as the power battery pack is used and ages, the self-discharge rate of each cell changes. The aforementioned self-discharge testing is only performed before shipment and cannot monitor the self-discharge of the power battery pack during use. Summary of the Invention

[0004] In order to solve the above technical problems, the present application provides a battery management method, a battery management device, a vehicle and a computer-readable storage medium, which can calculate the target equivalent self-discharge value of a single cell battery during its use, and can promptly identify single cells with abnormal self-discharge and manage the abnormal single cells.

[0005] The first aspect of the present application provides a battery management method, which includes: obtaining a current high-voltage inflection point power value corresponding to a high-voltage inflection point of a charging curve of each single cell at the current moment; obtaining a current historical cumulative balanced power value of each single cell at the current moment; obtaining a current equivalent self-discharge value of the single cell according to the current high-voltage inflection point power value of each single cell and the current historical cumulative balanced power value of the single cell; obtaining the equivalent self-discharge value of each single cell at the previous moment; and subtracting the equivalent self-discharge value of the single cell at the previous moment from the current equivalent self-discharge value of each single cell to obtain the current equivalent self-discharge value of the single cell. Obtaining a target equivalent self-discharge value of the single battery within the interval between the current moment and the previous moment; determining a maximum target equivalent self-discharge value and a minimum target equivalent self-discharge value among the target equivalent self-discharge values ​​of all single batteries; dividing the maximum target equivalent self-discharge value by the interval to obtain a maximum equivalent self-discharge rate, and dividing the minimum target equivalent self-discharge value by the interval to obtain a minimum equivalent self-discharge rate; and managing the target single battery corresponding to the maximum target equivalent self-discharge value when it is determined that the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold.

[0006] A second aspect of the present application further provides a battery management device, comprising: a plurality of single cells, an acquisition module, and a processing module. The acquisition module is configured to acquire a current high-voltage inflection point power value corresponding to a high-voltage inflection point of a charging curve of each single cell at the current moment, a current historical cumulative equalization power value of each single cell at the current moment, and an equivalent self-discharge value of each single cell at the previous moment. The processing module is configured to obtain a current equivalent self-discharge value of each single cell based on the current high-voltage inflection point capacity value of the single cell and the current historical accumulated equalization capacity value of the single cell, and to obtain a target equivalent self-discharge value of the single cell within an interval between the current and previous moments by subtracting the equivalent self-discharge value of the single cell from the current equivalent self-discharge value of each single cell, determine a maximum target equivalent self-discharge value and a minimum target equivalent self-discharge value among the target equivalent self-discharge values ​​of all single cells, divide the maximum target equivalent self-discharge value by the interval to obtain a maximum equivalent self-discharge rate, and divide the minimum target equivalent self-discharge value by the interval to obtain a minimum equivalent self-discharge rate, and manage the target single cell corresponding to the maximum target equivalent self-discharge value when it is determined that the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold.

[0007] A third aspect of the present application further provides a vehicle, comprising the battery management device as described above.

[0008] A fourth aspect of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program is called and executed by a processor to implement the aforementioned battery management method.

[0009] The battery management method, battery management device, vehicle, and computer-readable storage medium provided in the present application obtain the current high-voltage inflection point power value and the current historical accumulated equalization power value of the charging curve of each single cell to obtain the current equivalent self-discharge value of each single cell, and subtract the equivalent self-discharge value at the previous moment from the current equivalent self-discharge value to obtain the target equivalent self-discharge value of each single cell. This achieves monitoring of the self-discharge conditions of all single cells during use of the battery management device, and then calculates the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate based on the target equivalent self-discharge values ​​of all single cells. When the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, the target single cell with the largest equivalent self-discharge rate is managed, so that users can promptly discover single cells with abnormal self-discharge and repair or replace them. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the implementation. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0011] Figure 1 A flowchart of a battery management method provided in an embodiment of the present application.

[0012] Figure 2 A schematic diagram of a charging curve provided in an embodiment of the present application.

[0013] Figure 3 A schematic diagram of a voltage differential curve provided in an embodiment of the present application.

[0014] Figure 4 for Figure 1 Sub-flowchart of step S103 in .

[0015] Figure 5 This is a structural block diagram of the battery management device provided in an embodiment of the present application.

[0016] Figure 6 A structural block diagram of a vehicle provided in an embodiment of the present application.

[0017] Explanation of reference numerals: 100 - battery management device; 10 - acquisition module; 20 - processing module; 30 - communication module; 40 - storage module; 200 - vehicle; 50 - single battery. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0019] In the description of this application, unless otherwise specified or limited, the term "connection" should be understood in a broad sense. For example, it can mean a fixed connection, a detachable connection, or an integral connection; it can mean a direct connection, an indirect connection through an intermediate medium, or internal communication between two components; it can mean a communication connection; or it can mean an electrical connection. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0020] See also Figure 1 , Figure 1 This is a flow chart of a battery management method provided in an embodiment of the present application. The battery management method is applied to a battery management device, which includes a plurality of single cells. Figure 1 As shown, the battery management method includes the following steps:

[0021] S101: Obtaining a current high-voltage inflection point power value corresponding to a high-voltage inflection point of a charging curve of each single battery at the current moment.

[0022] S102: Obtain the current historical cumulative balanced power value of each single battery at the current moment.

[0023] S103: Obtaining a current equivalent self-discharge value of each single cell according to the current high-voltage inflection point capacity value of each single cell and the current historical accumulated equalization capacity value of the single cell.

[0024] S104: Obtain the equivalent self-discharge value of each single battery at the previous moment.

[0025] S105: Subtract the equivalent self-discharge value of each single cell from the current equivalent self-discharge value of the single cell at the previous moment to obtain a target equivalent self-discharge value of the single cell within the interval between the current moment and the previous moment.

[0026] S106: Determine a maximum target equivalent self-discharge value and a minimum target equivalent self-discharge value among the target equivalent self-discharge values ​​of all the single batteries.

[0027] S107: Dividing the maximum target equivalent self-discharge value by the interval time to obtain a maximum equivalent self-discharge rate, and dividing the minimum target equivalent self-discharge value by the interval time to obtain a minimum equivalent self-discharge rate.

[0028] S108: When it is determined that the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, managing the target single battery corresponding to the maximum target equivalent self-discharge value.

[0029] Please also refer to Figure 2 and Figure 3 , Figure 2 A schematic diagram of a charging curve provided in an embodiment of the present application, Figure 3 This is a schematic diagram of a voltage differential curve provided by an embodiment of the present application. In the battery management device, all cells are connected in series. When charging all cells, the vehicle collects and records the parameters of each cell in real time. The parameters include voltage, current, temperature, SOC (state of charge), etc. By performing data processing on the parameters, such as filtering, differentiation, integration, summation, wavelet analysis, neural network operation, etc., the charging curve of each cell can be obtained, as shown in FIG. Figure 2 As shown, the charging curve is a voltage-capacity curve, that is, a curve showing the relationship between voltage and capacity. The voltage-capacity curve has three intervals where the voltage changes slowly. The interval where the voltage changes slowly is a voltage platform area. There is an area where the voltage changes quickly between two adjacent voltage platform areas. The point where the voltage changes fastest in the area where the voltage changes quickly is a voltage inflection point. There are two voltage inflection points in the voltage-capacity curve, which are the high voltage inflection point ( Figure 2 B) and the low voltage inflection point ( Figure 2 A in FIG), the high voltage inflection point and the low voltage inflection point correspond to voltage difference curves (such as Figure 3 As shown in FIG, there are two maximum points (maximum point C and maximum point D) on the high voltage inflection point B, wherein the high voltage inflection point B corresponds to the maximum point C, and the low voltage inflection point A corresponds to the maximum point D.

[0030] The current historical accumulated balanced power value is the accumulated value of the balanced power value obtained at the current moment and each balanced power value obtained before the current moment.

[0031] In some embodiments, the equivalent self-discharge value of each single cell at the last moment is the high voltage inflection point value of each single cell at the last moment minus the historical cumulative balanced power value of the single cell at the last moment. The historical cumulative balanced power value at the last moment is the sum of the balanced power value obtained at the last moment and each balanced power value obtained before the last moment.

[0032] During the use of the single cell, the single cell will self-discharge due to the current manufacturing process. The self-discharge process of each single cell is different, resulting in inconsistent self-discharge rates of the multiple single cells. Since the self-discharge process of the single cell will cause the high voltage inflection point power value to shift, and the self-discharge rates of the multiple single cells are inconsistent, the degree of shift of the high voltage inflection point power values ​​of the multiple single cells is inconsistent, resulting in different high voltage inflection point power values ​​obtained for all single cells. In order to compensate for the inconsistent remaining power of the single cells due to the inconsistent self-discharge rates of the single cells, the battery management device can balance the multiple single cells. Specifically, it compares the remaining power of all single cells and discharges the single cells with higher remaining power so that the single cells generate corresponding balanced power. The less the self-discharge of the single cell, the more balanced power generated. Therefore, the equivalent self-discharge value of the single cell can be calculated by using the high voltage inflection point power value and the historical accumulated equalization power value of the single cell, wherein the equivalent self-discharge value is a relative self-discharge value. Since the absolute self-discharge value cannot be calculated, in this application, the equivalent self-discharge value is the relative self-discharge value of each single cell.

[0033] In some embodiments, the last moment is the moment when the vehicle leaves the factory, the equivalent self-discharge value of each single cell at the last moment is 0, the historical accumulated balanced power value of each single cell at the last moment is 0, and the high voltage inflection point power value of each single cell at the last moment is 0.

[0034] In some embodiments, the current moment is the moment when the charging curve is obtained during current charging, and the previous moment is the moment when the charging curve is obtained during the previous charging.

[0035] In some embodiments, the interval between the current moment and the previous moment is a preset interval, that is, the current moment is the time equal to the previous moment plus the preset interval. The preset interval can be set according to actual needs, for example, 3 months.

[0036] The number of the plurality of single cells can be set according to actual needs and is not limited here.

[0037] In some embodiments, the single cell battery may be a power battery, and the battery management device may be applied to a vehicle, such as a pure electric vehicle or a hybrid vehicle. In other embodiments, the single cell battery may be an energy storage battery, and the battery management device may be applied to energy storage power stations, peak-shaving and frequency-regulating power auxiliary services, etc.

[0038] In step S106, when determining the maximum target equivalent self-discharge value and the minimum target equivalent self-discharge value among the target equivalent self-discharge values ​​of all single cells, the maximum target equivalent self-discharge value and the minimum target equivalent self-discharge value are determined by comparing the obtained target equivalent self-discharge values ​​of all single cells.

[0039] In step S108, the preset threshold can be set according to actual needs and is not limited here.

[0040] The following further describes steps S106 to S108 in detail by taking the battery management device including 8 single batteries as an example.

[0041] The set of target equivalent self-discharge values ​​of all single cells in the battery management device is {2, 3, 2, 3, 1, 6, 3, 3}. By comparing the target equivalent self-discharge values ​​of all single cells, the minimum target equivalent self-discharge value is determined to be 1, and the maximum target equivalent self-discharge value is determined to be 6. The value of the interval duration is preset to 2, and the maximum equivalent self-discharge rate (3) is obtained by dividing the maximum target equivalent self-discharge value by the interval duration, and the minimum equivalent self-discharge rate (0.5) is obtained by dividing the minimum target equivalent self-discharge value by the interval duration. When it is determined that the difference (2.5) between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold (preset to 2), the target single cell corresponding to the maximum target equivalent self-discharge value is managed, that is, the single cell with a target equivalent self-discharge value of 6 is managed.

[0042] The battery management method provided in the embodiment of the present application obtains the current high-voltage inflection point power value and the current historical accumulated equalization power value of the charging curve of each single cell to obtain the current equivalent self-discharge value of each single cell, and subtracts the equivalent self-discharge value at the previous moment from the current equivalent self-discharge value to obtain the target equivalent self-discharge value of each single cell. This achieves monitoring of the self-discharge conditions of all single cells during use of the battery management device, and then calculates the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate based on the target equivalent self-discharge values ​​of all single cells. When the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, the target single cell with the largest equivalent self-discharge rate is managed, so that users can promptly discover single cells with abnormal self-discharge and repair or replace them.

[0043] See also Figure 4 , Figure 4 for Figure 1 In some embodiments, as shown in FIG. Figure 4 As shown, the current equivalent self-discharge value of each single cell is obtained according to the current high voltage inflection point power value of each single cell and the current historical accumulated balanced power value of the single cell, including:

[0044] S1031: Determine the minimum current high-voltage inflection point power value among the current high-voltage inflection point power values ​​of all single batteries.

[0045] S1032: Subtract the minimum current high-voltage inflection point power value from the current high-voltage inflection point power value of each single cell to obtain a pre-processed current high-voltage inflection point power value of each single cell.

[0046] S1033: Determine the minimum current historical accumulated equalization power value among the current historical accumulated equalization power values ​​of all single cells.

[0047] S1034: Subtract the minimum current historical cumulative balancing power value from the current historical cumulative balancing power value of each single cell to obtain a pre-processed current historical cumulative balancing power value of each single cell.

[0048] S1035: Subtract the pre-processed current historical accumulated equalization capacity value of each single cell from the pre-processed current high voltage inflection point capacity value of the single cell to obtain the current equivalent self-discharge capacity value of the single cell.

[0049] When determining the minimum current high voltage inflection point power value among the current high voltage inflection point power values ​​of all single cells, the minimum current high voltage inflection point power value is determined by comparing the acquired current high voltage inflection point power values ​​of all single cells.

[0050] When determining the minimum current historical accumulated equalization power value among the current historical accumulated equalization power values ​​of all single cells, the minimum current historical accumulated equalization power value is determined by comparing the acquired current historical accumulated equalization power values ​​of all single cells.

[0051] The following further describes steps S1031 to S1035 in detail by taking the battery management device including 8 single batteries as an example.

[0052] The set of current high voltage inflection point power values ​​of all single cells in the battery management device is {4, 6, 8, 5, 1, 7, 5, 3}. By comparing the current high voltage inflection point power values ​​of all single cells, the minimum current high voltage inflection point power value can be determined to be 1. The pre-processed current high voltage inflection point power value of each single cell is obtained by subtracting the minimum current high voltage inflection point power value from the current high voltage inflection point power value of each single cell, thereby obtaining the set of pre-processed current high voltage inflection point power values ​​of all single cells {3, 5, 7, 4, 0, 6, 4, 2}. The set of current historical accumulated equalization power values ​​of all single cells in the battery management device is {2, 4, 5,6, 3, 4, 5, 3}, by comparing the current historical cumulative balancing power values ​​of all single cells, the minimum current historical cumulative balancing power value can be determined to be 2; the pre-processed current historical cumulative balancing power value of each single cell is subtracted from the minimum current historical cumulative balancing power value from the current historical cumulative balancing power value of each single cell to obtain the pre-processed current historical cumulative balancing power value of each single cell, thereby obtaining the set of pre-processed current historical cumulative balancing power values ​​of all single cells {0, 2, 3, 4, 1, 2, 3, 1}; the pre-processed current high voltage inflection point power value of each single cell is subtracted from the pre-processed current historical cumulative balancing power value of the single cell to obtain the current equivalent self-discharge power value of the single cell, thereby obtaining the set of current equivalent self-discharge power values ​​of all single cells {3, 2, 4, 0, -1, 4, 1, 1}.

[0053] Thus, in some embodiments, by normalizing the current high voltage inflection point power values ​​of all single cells and normalizing the current historical cumulative power values ​​of all single cells, these preprocessings are performed, that is, subtracting the minimum current high voltage inflection point power value from the current high voltage inflection point power value of each single cell to obtain the preprocessed current high voltage inflection point power value of each single cell, and subtracting the minimum current historical cumulative balancing power value from the current historical cumulative balancing power value of each single cell to obtain the preprocessed current historical cumulative balancing power value of each single cell, and then subtracting the preprocessed current historical cumulative balancing power value from the preprocessed current high voltage inflection point power value to obtain the current equivalent self-discharge value, the space required to store the current equivalent self-discharge value can be reduced, the requirement for memory can be reduced, and cost can be saved.

[0054] In some other embodiments, obtaining the current equivalent self-discharge value of each single cell based on the current high-voltage inflection point power value of each single cell and the current historical cumulative equalization power value of the single cell includes: subtracting the current historical cumulative equalization power value of each single cell from the current high-voltage inflection point power value of each single cell to obtain the current equivalent self-discharge value of the single cell. That is, in other embodiments, the current high-voltage inflection point power value and the current historical cumulative equalization power value do not need to be preprocessed, and the current equivalent self-discharge value is obtained by directly subtracting the current historical cumulative equalization power value from the current high-voltage inflection point power value, thereby reducing the number of calculations and saving battery power.

[0055] In some embodiments, the battery management device is applied to a vehicle, and the management of the target single battery corresponding to the maximum target equivalent self-discharge value includes: sending information of the target single battery to the vehicle and / or a terminal connected to the vehicle.

[0056] The target battery information may include the target battery number, location, target equivalent self-discharge value, and equivalent self-discharge rate, and the target battery information is transmitted to the vehicle and / or a terminal connected to the vehicle, such as a user's mobile phone. Upon receiving the information, the vehicle controls a display to display the information and issue a warning signal, and / or the terminal controls the display to display the information and issue a warning signal, reminding the user to repair or replace the target battery as soon as possible.

[0057] The battery management method provided in the embodiment of the present application, when determining that the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, sends information of the target single battery corresponding to the maximum target equivalent self-discharge value to the vehicle and / or a terminal communicatively connected to the vehicle. The user can be informed of the information of the single battery with abnormal self-discharge and be reminded so that the user can take countermeasures for the abnormal single battery in a timely manner.

[0058] In some embodiments, the battery management device further includes multiple reminder modules, each corresponding to a single battery cell. The management of the target single battery cell corresponding to the maximum target equivalent self-discharge value further includes controlling the reminder module corresponding to the target single battery cell to issue a warning signal. By controlling the reminder module corresponding to the target single battery cell to issue a warning signal, a user can promptly identify single batteries with abnormal self-discharge and repair or replace them.

[0059] The reminder module may be a buzzer component, a voice component, a warning light, etc.

[0060] In some embodiments, the battery management method further includes: replacing the previous equivalent self-discharge value of each single cell with the current equivalent self-discharge value of the single cell to update the stored equivalent self-discharge value of the single cell. Figure 5 The current equivalent self-discharge value replaces the previous equivalent self-discharge value in the storage module 40 of the battery management device 100 shown in FIG. This value is used to calculate the target equivalent self-discharge value at the next moment. The next time the target equivalent self-discharge value is calculated, the current equivalent self-discharge value is used as the previous equivalent self-discharge value.

[0061] In some embodiments, replacing the last-moment equivalent self-discharge value of each single cell with the current equivalent self-discharge value of the single cell to update the stored equivalent self-discharge value of the single cell includes: determining the minimum current equivalent self-discharge value among the current equivalent self-discharge values ​​of all cells; subtracting the minimum current equivalent self-discharge value from the current equivalent self-discharge value of each single cell to obtain a pre-processed current equivalent self-discharge value of each single cell; and replacing the last-moment equivalent self-discharge value of the single cell with the pre-processed current equivalent self-discharge value of each single cell to update the stored equivalent self-discharge value of the single cell. When calculating the target equivalent self-discharge value next time, the pre-processed current equivalent self-discharge value is the equivalent self-discharge value at the last moment.

[0062] The above steps will be further specifically described below by taking the battery management device including 8 single batteries as an example.

[0063] The set of current equivalent self-discharge values ​​of all single cells in the battery management device is {5, 7, 4, 3, 2, 7, 8, 4}, and the minimum current equivalent self-discharge value is determined to be 2 by comparing the current equivalent self-discharge values ​​of all single cells; the pre-processed current equivalent self-discharge value of each single cell is obtained by subtracting the minimum current equivalent self-discharge value from the current equivalent self-discharge value of each single cell, thereby obtaining the set of pre-processed current equivalent self-discharge values ​​of all single cells as {3, 5, 2, 1, 0, 5, 6, 2}; and the set of pre-processed current equivalent self-discharge values ​​of all single cells replaces the set of equivalent self-discharge values ​​of all single cells at the previous moment.

[0064] The battery management method provided in the embodiment of the present application performs pre-processing on the current equivalent self-discharge values ​​of all single cells to normalize them. That is, the current equivalent self-discharge value of each single cell is subtracted from the minimum current equivalent self-discharge value of the single cell to obtain the pre-processed current equivalent self-discharge values ​​of all single cells. The pre-processed current equivalent self-discharge values ​​of all single cells are then stored. This can reduce the space required to store the pre-processed current equivalent self-discharge values, lower the requirements for memory, and save costs.

[0065] See also Figure 5 , Figure 5 This is a structural block diagram of the battery management device 100 provided in an embodiment of the present application. Figure 5As shown, the battery management device 100 includes a plurality of single cells 50, an acquisition module 10, and a processing module 20. The acquisition module 10 is configured to acquire the current high-voltage inflection point power value corresponding to the high-voltage inflection point of the charging curve of each single cell 50 at the current moment, the current historical accumulated balanced power value of each single cell 50 at the current moment, and the equivalent self-discharge value of each single cell 50 at the previous moment. The processing module 20 is configured to obtain a current equivalent self-discharge value of each single cell 50 based on the current high-voltage inflection point capacity value of the single cell 50 and the current historical accumulated equalization capacity value of the single cell 50, and to subtract the equivalent self-discharge value of the single cell 50 at a previous moment from the current equivalent self-discharge value of each single cell 50 to obtain a target equivalent self-discharge value of the single cell 50 within the interval between the current moment and the previous moment. The processing module 20 is configured to determine a maximum target equivalent self-discharge value and a minimum target equivalent self-discharge value among the target equivalent self-discharge values ​​of all the single cells 50, divide the maximum target equivalent self-discharge value by the interval to obtain a maximum equivalent self-discharge rate, and divide the minimum target equivalent self-discharge value by the interval to obtain a minimum equivalent self-discharge rate. When it is determined that the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, the target single cell 50 corresponding to the maximum target equivalent self-discharge value is managed.

[0066] In some embodiments, the acquisition module 10 and the processing module 20 may be processing chips such as a processor, a single chip microcomputer, a controller, etc., and the acquisition module 10 and the processing module 20 may be separate processing chips or integrated processing chips.

[0067] The battery management device 100 provided in the embodiment of the present application obtains the current high-voltage inflection point power value and the current historical accumulated equalization power value of the charging curve of each single cell 50 to obtain the current equivalent self-discharge value of each single cell 50, and subtracts the equivalent self-discharge value at the previous moment from the current equivalent self-discharge value to obtain the target equivalent self-discharge value of each single cell 50. This enables the self-discharge status of all single cells 50 to be monitored during use of the battery management device 100, and the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate to be calculated based on the target equivalent self-discharge values ​​of all single cells 50. When the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, the target single cell 50 with the largest equivalent self-discharge rate is managed, so that the user can promptly discover single cells with abnormal self-discharge and repair or replace them.

[0068] In some embodiments, obtaining the current equivalent self-discharge value of the single cell 50 based on the current high voltage inflection point power value of each single cell 50 and the current historical accumulated balancing power value of the single cell 50 includes: the processing module 20 determining the minimum current high voltage inflection point power value among the current high voltage inflection point power values ​​of all the single cells 50; subtracting the minimum current high voltage inflection point power value from the current high voltage inflection point power value of each single cell 50 to obtain a pre-processed current high voltage inflection point power value of each single cell 50; determining the minimum current historical accumulated balancing power value among the current historical accumulated balancing power values ​​of all the single cells 50; subtracting the minimum current historical accumulated balancing power value from the current historical accumulated balancing power value of each single cell 50 to obtain a pre-processed current historical accumulated balancing power value of each single cell 50; and subtracting the pre-processed current historical accumulated balancing power value of each single cell 50 from the pre-processed current high voltage inflection point power value of each single cell 50 to obtain the current equivalent self-discharge value of the single cell 50.

[0069] The battery management device 100 provided in the embodiment of the present application performs preprocessing by normalizing the current high-voltage inflection point power values ​​of all single cells 50 and normalizing the current historical cumulative power values ​​of all single cells 50. That is, the preprocessed current high-voltage inflection point power value of each single cell 50 is obtained by subtracting the minimum current high-voltage inflection point power value from the current high-voltage inflection point power value of each single cell 50, and the preprocessed current historical cumulative balancing power value of each single cell 50 is obtained by subtracting the minimum current historical cumulative balancing power value from the current historical cumulative balancing power value of each single cell 50. The current equivalent self-discharge value is then obtained by subtracting the preprocessed current historical cumulative balancing power value from the preprocessed current high-voltage inflection point power value. This can reduce the space required to store the current equivalent self-discharge value, reduce the memory requirements, and save costs.

[0070] In some other embodiments, obtaining the current equivalent self-discharge value of the single cell 50 based on the current high-voltage inflection point power value of each single cell 50 and the current historical accumulated equalization power value of the single cell 50 includes: the processing module 20 subtracting the current historical accumulated equalization power value of each single cell 50 from the current high-voltage inflection point power value of each single cell 50 to obtain the current equivalent self-discharge value of the single cell 50. That is, in other embodiments, there is no need to pre-process the current high-voltage inflection point power value and the current historical accumulated equalization power value; the current equivalent self-discharge value is obtained by directly subtracting the current historical accumulated equalization power value from the current high-voltage inflection point power value, thereby reducing the number of calculations and saving battery power.

[0071] In some embodiments, the battery management device 100 is applied to a vehicle, such as Figure 5 As shown, the battery management device 100 also includes a communication module 30 for communicating with the vehicle. The management of the target single battery 50 corresponding to the maximum target equivalent self-discharge value includes: sending the information of the target single battery 50 to the vehicle and / or a terminal connected to the vehicle through the communication module 30.

[0072] Among them, the battery management device 100 can send the number, location, target equivalent self-discharge value and equivalent self-discharge rate of the target single battery 50 to the vehicle and / or the terminal connected to the vehicle through the communication module 30, so that the user can promptly discover the single battery with abnormal self-discharge and repair or replace it.

[0073] In some embodiments, the battery management device 100 further includes a plurality of reminder modules (not shown in the figure), each reminder module corresponding to a single cell 50, and the management of the target single cell 50 corresponding to the maximum target equivalent self-discharge value includes: controlling the reminder module corresponding to the target single cell 50 to send an early warning signal.

[0074] In some embodiments, the reminder module may be a buzzer component, a voice component, a warning light, etc.

[0075] When the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, the processing module 20 determines the target battery cell 50 corresponding to the maximum equivalent self-discharge rate and controls the reminder module corresponding to the target battery cell 50 to issue a warning signal. For example, the multiple battery cells are pre-numbered, and the multiple reminder modules have numbers corresponding to the numbers of the multiple battery cells. When the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, the processing module 20 determines the number of the target battery cell 50 and controls the reminder module with the same number as the target battery cell 50 to issue a warning signal, such as a buzzer, voice broadcast, or flashing warning light, to alert the user that the battery cell self-discharge is abnormal and inform the user of the number of the abnormal battery cell, so that the user can clearly identify the location of the abnormal battery cell and promptly repair or replace it.

[0076] In some embodiments, as Figure 5As shown, the battery management device 100 further includes a storage module 40, which stores the equivalent self-discharge value of each single battery 50. The processing module 20 is further configured to replace the previous equivalent self-discharge value of each single battery 50 with the current equivalent self-discharge value of the single battery 50, thereby updating the equivalent self-discharge value of the single battery 50 stored in the storage module 40 for use in calculating the target equivalent self-discharge value at the next moment. When the target equivalent self-discharge value is calculated the next time, the current equivalent self-discharge value is the equivalent self-discharge value at the previous moment.

[0077] In some embodiments, replacing the previous equivalent self-discharge value of each single cell 50 with the current equivalent self-discharge value of the single cell 50 to update the equivalent self-discharge value of the single cell 50 stored in the storage module 40 includes: determining the minimum current equivalent self-discharge value among the current equivalent self-discharge values ​​of all cells; subtracting the minimum current equivalent self-discharge value from the current equivalent self-discharge value of each single cell 50 to obtain a pre-processed current equivalent self-discharge value of each single cell 50; and replacing the previous equivalent self-discharge value of the single cell 50 with the pre-processed current equivalent self-discharge value of each single cell 50 to update the stored equivalent self-discharge value of the single cell 50. When calculating the target equivalent self-discharge value next time, the pre-processed current equivalent self-discharge value is the equivalent self-discharge value at the previous moment.

[0078] In some embodiments, the storage module 40 also stores the current charging curve of each single battery 50 and the current high voltage inflection point power value, so that the acquisition module 10 can obtain the current high voltage inflection point power value of each single battery 50 at the current moment.

[0079] In some embodiments, the storage module 40 also stores the current historical accumulated equalization power value of each single battery 50 at the current moment, so that the acquisition module 10 can acquire the current high voltage inflection point power value of each single battery 50 at the current moment.

[0080] The storage module 40 may be a non-volatile memory, such as FRAM (Ferroelectric Random Access Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), EPROM (Erasable Programmable Read Only Memory), etc.

[0081] The battery management device 100 provided in the embodiment of the present application pre-processes the current equivalent self-discharge values ​​of all single cells 50 by normalizing them, that is, subtracting the minimum current equivalent self-discharge value of the single cell 50 from the current equivalent self-discharge value of each single cell 50 to obtain the pre-processed current equivalent self-discharge values ​​of all single cells 50, and then storing the pre-processed current equivalent self-discharge values ​​of all single cells 50. This can reduce the space required to store the pre-processed current equivalent self-discharge values, reduce the requirements for memory, and save costs.

[0082] Among them, the battery management device 100 corresponds to the aforementioned battery management method. For more detailed description, please refer to the contents of each embodiment of the aforementioned battery management method. The contents of the battery management device 100 and the aforementioned battery management method can also refer to each other.

[0083] See also Figure 6 , Figure 6 This is a structural block diagram of the vehicle 200 provided in the embodiment of the present application. Figure 6 As shown, the vehicle 200 includes the battery management device 100 provided by any of the aforementioned embodiments.

[0084] The vehicle 200 may be a pure electric vehicle or a hybrid vehicle, for example, a pure electric vehicle, a pure electric truck, a hybrid truck, etc.

[0085] An embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program is invoked and executed by a processor to implement the battery management method provided in any of the aforementioned embodiments.

[0086] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable memory, which may include: a flash drive, a read-only memory, a random access memory, a magnetic disk or an optical disk, etc.

[0087] It should be noted that for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

[0088] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0089] The above is an implementation method of the embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the embodiment of the present application. These improvements and modifications are also considered to be within the scope of protection of the present application.

Claims

1. A battery management method, applied to a battery management device, wherein the battery management device includes a plurality of single batteries, characterized in that: The battery management method comprises the following steps: Obtain the current high voltage inflection point power value corresponding to the high voltage inflection point of the charging curve of each single battery at the current moment; Get the current historical cumulative balanced power value of each single battery at the current moment; Obtaining a current equivalent self-discharge value of each single cell according to the current high voltage inflection point capacity value of each single cell and the current historical accumulated equalization capacity value of the single cell; Obtain the equivalent self-discharge value of each single battery at the last moment; Subtract the equivalent self-discharge value of each single cell at the previous moment from the current equivalent self-discharge value of the single cell to obtain a target equivalent self-discharge value of the single cell within the interval between the current moment and the previous moment; Determining a maximum target equivalent self-discharge value and a minimum target equivalent self-discharge value among the target equivalent self-discharge values ​​of all single batteries; Dividing the maximum target equivalent self-discharge value by the interval duration to obtain a maximum equivalent self-discharge rate, and dividing the minimum target equivalent self-discharge value by the interval duration to obtain a minimum equivalent self-discharge rate; and When it is determined that the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold, the target single battery corresponding to the maximum target equivalent self-discharge value is managed.

2. The battery management method according to claim 1, characterized in that: Obtaining the current equivalent self-discharge value of each single cell according to the current high voltage inflection point power value of each single cell and the current historical accumulated balanced power value of the single cell includes: The current high voltage inflection point capacity value of each single cell is subtracted from the current historical accumulated equalization capacity value of the single cell to obtain the current equivalent self-discharge capacity value of the single cell.

3. The battery management method according to claim 1, characterized in that: Obtaining the current equivalent self-discharge value of each single cell according to the current high voltage inflection point power value of each single cell and the current historical accumulated balanced power value of the single cell includes: Determine the minimum current high-voltage inflection point power value among the current high-voltage inflection point power values ​​of all single batteries; Subtracting the minimum current high-voltage inflection point power value from the current high-voltage inflection point power value of each single cell to obtain a pre-processed current high-voltage inflection point power value of each single cell; Determine the minimum current historical cumulative equalization power value among the current historical cumulative equalization power values ​​of all single batteries; Subtracting the minimum current historical cumulative equalization power value from the current historical cumulative equalization power value of each single cell to obtain a pre-processed current historical cumulative equalization power value of each single cell; and The pre-processed current high voltage inflection point capacity value of each single cell is subtracted from the pre-processed current historical accumulated equalization capacity value of the single cell to obtain the current equivalent self-discharge capacity value of the single cell.

4. The battery management method according to claim 1, characterized in that: The battery management device is applied to a vehicle, and managing the target single battery corresponding to the maximum target equivalent self-discharge value includes: The information of the target single battery is sent to the vehicle and / or a terminal connected to the vehicle for communication.

5. The battery management method according to claim 1, characterized in that: The battery management device further includes a plurality of reminder modules, each reminder module corresponding to a single battery, and the management of the target single battery corresponding to the maximum target equivalent self-discharge value further includes: Control the reminder module corresponding to the target single battery to send out an early warning signal.

6. The battery management method according to claim 1, characterized in that: The method further includes: replacing the previous equivalent self-discharge value of each single battery with the current equivalent self-discharge value of the single battery to update the stored equivalent self-discharge value of the single battery.

7. The battery management method according to claim 6, characterized in that: The replacing the previous equivalent self-discharge value of each single battery cell with the current equivalent self-discharge value of the single battery cell to update the stored equivalent self-discharge value of the single battery cell includes: determining a minimum current equivalent self-discharge value among the current equivalent self-discharge values ​​of all batteries; Subtracting the minimum current equivalent self-discharge value from the current equivalent self-discharge value of each single battery cell to obtain a pre-processed current equivalent self-discharge value of each single battery cell; and The pre-processed current equivalent self-discharge value of each single battery replaces the previous equivalent self-discharge value of the single battery to update the stored equivalent self-discharge value of the single battery.

8. A battery management device, comprising a plurality of single cells, characterized in that: The battery management device further includes: An acquisition module is used to obtain the current high-voltage inflection point power value corresponding to the high-voltage inflection point of the charging curve of each single cell at the current moment, the current historical accumulated balanced power value of each single cell at the current moment, and the equivalent self-discharge value of each single cell at the previous moment; The processing module is configured to obtain a current equivalent self-discharge value of each single cell based on the current high-voltage inflection point power value of the single cell and the current historical accumulated equalization power value of the single cell, and to subtract the equivalent self-discharge value of the single cell at a previous moment from the current equivalent self-discharge value of each single cell to obtain a target equivalent self-discharge value of the single cell within an interval between the current moment and the previous moment, determine a maximum target equivalent self-discharge value and a minimum target equivalent self-discharge value among the target equivalent self-discharge values ​​of all single cells, divide the maximum target equivalent self-discharge value by the interval to obtain a maximum equivalent self-discharge rate, and divide the minimum target equivalent self-discharge value by the interval to obtain a minimum equivalent self-discharge rate, and manage the target single cell corresponding to the maximum target equivalent self-discharge value when it is determined that the difference between the maximum equivalent self-discharge rate and the minimum equivalent self-discharge rate is greater than a preset threshold.

9. The battery management device according to claim 8, characterized in that: Obtaining the current equivalent self-discharge value of each single cell according to the current high voltage inflection point power value of each single cell and the current historical accumulated balanced power value of the single cell includes: The current high voltage inflection point capacity value of each single cell is subtracted from the current historical accumulated equalization capacity value of the single cell to obtain the current equivalent self-discharge capacity value of the single cell.

10. The battery management device according to claim 8, characterized in that: Obtaining the current equivalent self-discharge value of each single cell according to the current high voltage inflection point power value of each single cell and the current historical accumulated balanced power value of the single cell includes: Determine the minimum current high-voltage inflection point power value among the current high-voltage inflection point power values ​​of all single batteries; Subtracting the minimum current high-voltage inflection point power value from the current high-voltage inflection point power value of each single cell to obtain a pre-processed current high-voltage inflection point power value of each single cell; Determine the minimum current historical cumulative equalization power value among the current historical cumulative equalization power values ​​of all single batteries; Subtracting the minimum current historical cumulative equalization power value from the current historical cumulative equalization power value of each single cell to obtain a pre-processed current historical cumulative equalization power value of each single cell; and The pre-processed current high voltage inflection point capacity value of each single cell is subtracted from the pre-processed current historical accumulated equalization capacity value of the single cell to obtain the current equivalent self-discharge capacity value of the single cell.

11. The battery management device according to claim 8, characterized in that: The battery management device is applied to a vehicle, and further comprises a communication module for communicating with the vehicle. The management of the target single battery corresponding to the maximum target equivalent self-discharge value comprises: The information of the target single battery is sent to the vehicle and / or a terminal connected to the vehicle for communication via the communication module.

12. The battery management device according to claim 8, characterized in that: The battery management device further includes a plurality of reminder modules, each reminder module corresponding to a single battery, and the management of the target single battery corresponding to the maximum target equivalent self-discharge value includes: Control the reminder module corresponding to the target single battery to send out an early warning signal.

13. The battery management device according to claim 8, characterized in that: The battery management device also includes a storage module, which stores the equivalent self-discharge value of each single cell. The processing module is also used to replace the equivalent self-discharge value of each single cell at the previous moment with the current equivalent self-discharge value of the single cell to update the stored equivalent self-discharge value of the single cell.

14. The battery management device according to claim 13, characterized in that: The replacing the previous equivalent self-discharge value of each single battery cell with the current equivalent self-discharge value of the single battery cell to update the stored equivalent self-discharge value of the single battery cell includes: determining a minimum current equivalent self-discharge value among the current equivalent self-discharge values ​​of all batteries; Subtracting the minimum current equivalent self-discharge value from the current equivalent self-discharge value of each single battery cell to obtain a pre-processed current equivalent self-discharge value of each single battery cell; and The pre-processed current equivalent self-discharge value of each single battery replaces the previous equivalent self-discharge value of the single battery to update the stored equivalent self-discharge value of the single battery.

15. A vehicle, characterized in that: A battery management device comprising the battery according to any one of claims 8 to 14.

16. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, which is called and executed by a processor to implement the battery management method according to any one of claims 1 to 7.

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