Battery equalization control method and device, equipment and storage medium

Abstract

The invention discloses a battery equalization control method, device and equipment and a storage medium, and relates to the technical field of batteries, and the method comprises the steps: collecting the voltage and temperature of each battery cell corresponding to each single battery cell; based on the voltage of each battery cell, judging whether equalization control needs to be carried out on each single battery cell or not; and when it is determined that equalization control needs to be performed on each single cell, based on the voltage of each cell and the temperature of each cell, starting a corresponding one of the active equalization circuit and the passive equalization circuit to perform equalization control on each single cell. Whether equalization control needs to be carried out on each single battery cell is judged by acquiring each battery cell voltage and each battery cell temperature of each single battery cell in a plurality of battery packs which are connected in series, and a specific mode for carrying out equalization control on each single battery cell at present is selected according to each battery cell voltage and each battery cell temperature. Therefore, the equalization control mode can be adaptively adjusted under the condition of temperature change, and different requirements corresponding to equalization control in different scenes are met.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery balancing control method, device, equipment and storage medium. Background Art

[0002] As the core component of the three-electric system of new energy vehicles, the power battery can be specifically composed of multiple battery packs connected in series, and each battery pack is composed of multiple single cells connected in series. During the charging and discharging process of the power battery, since charging and discharging will consume a part of the electric energy, the temperature of each single cell will be different, resulting in a large difference in the internal resistance of each single cell, which will cause imbalance in each single cell or each battery pack. Generally, each battery cell can be balanced by passive balancing, but the balancing current of passive balancing is small, and the balancing effect is poor for high-voltage batteries with excessive voltage differences. In addition, due to the influence of temperature, the passive balancing method is difficult to meet the changing balancing needs, so it is difficult to effectively balance each single cell or each battery pack. Summary of the invention

[0003] The main purpose of the present application is to provide a battery balancing control method, device, equipment and storage medium, aiming to solve the technical problem of how to select a corresponding balancing method according to different battery cell temperatures and battery cell voltages to effectively maintain balance between each single battery cell in a plurality of battery packs connected in series.

[0004] To achieve the above object, the present application provides a battery balancing control method, which is applied to a battery balancing system. The battery balancing system includes a plurality of battery packs connected in series, each of the battery packs includes a plurality of single cells, and each of the single cells is connected to an active balancing circuit and a passive balancing circuit. The steps of the battery balancing control method include:

[0005] Collecting the voltage of each battery cell and the temperature of each battery cell corresponding to each of the single battery cells;

[0006] Based on the voltage of each battery cell, determining whether it is necessary to perform balancing control on each of the single battery cells;

[0007] When it is determined that the battery cells need to be balanced, based on the battery cell voltages and the battery cell temperatures, a corresponding one of the active balancing circuit or the passive balancing circuit is turned on to perform balanced control on the battery cells.

[0008] In one embodiment, the step of judging whether it is necessary to perform balancing control on each of the battery cells based on the voltage of each of the battery cells comprises:

[0009] Screening out a maximum cell voltage and a minimum cell voltage from the cell voltages, and obtaining a maximum voltage difference between the maximum cell voltage and the minimum cell voltage;

[0010] When the maximum voltage difference is greater than a preset voltage difference threshold, determining that each of the single cells needs to be balanced;

[0011] Or, when the maximum voltage difference is not greater than the voltage difference threshold, it is determined that there is no need to perform balancing control on each of the single battery cells.

[0012] In one embodiment, when it is determined that each of the single cells needs to be balanced, based on the voltage of each cell and the temperature of each cell, the step of starting a corresponding one of the active balancing circuit or the passive balancing circuit to perform balanced control on each of the single cells includes:

[0013] When it is determined that each of the single cells needs to be balanced, a corresponding balancing strategy is selected based on the voltage of each cell and the temperature of each cell;

[0014] When the balancing strategy is an active balancing strategy, turning on the active balancing circuit to perform active balancing control on each of the single cells;

[0015] Or, when the balancing strategy is a passive balancing strategy, the passive balancing circuit is turned on to perform passive balancing control on each of the single cells.

[0016] In one embodiment, when it is determined that the balancing control needs to be performed on each of the single battery cells, the step of selecting a corresponding balancing strategy based on the voltage of each of the battery cells and the temperature of each of the battery cells includes:

[0017] Acquire a maximum voltage difference between a maximum cell voltage and a minimum cell voltage through each of the cell voltages, and acquire a target cell temperature corresponding to a single cell of the maximum cell voltage through each of the cell temperatures;

[0018] Based on the target battery cell temperature and the maximum voltage difference, the corresponding balancing strategy is selected.

[0019] In one embodiment, the step of selecting the corresponding balancing strategy based on the target battery cell temperature and the maximum voltage difference includes:

[0020] When the maximum voltage difference is between the voltage difference threshold and the first preset voltage difference and the target cell temperature is between the minimum allowable temperature and the maximum allowable temperature, the balancing strategy is selected as the passive balancing strategy, and the first preset voltage difference is greater than the voltage difference threshold;

[0021] Or, when the maximum voltage difference is between the first preset voltage difference and the second preset voltage difference and the target cell temperature is between the minimum allowable temperature and a preset cell temperature threshold, the balancing strategy is selected as the active balancing strategy, the second preset voltage difference is greater than the first preset voltage difference, and the cell temperature threshold is between the maximum allowable temperature and the minimum allowable temperature;

[0022] Or, when the maximum voltage difference is between the first preset voltage difference and the second preset voltage difference and the target battery cell temperature is between the battery cell temperature threshold and the maximum allowable temperature, the balancing strategy is selected as the passive balancing strategy.

[0023] In one embodiment, the step of selecting the corresponding balancing strategy based on the target battery cell temperature and the maximum voltage difference further includes:

[0024] When the maximum voltage difference is lower than the voltage difference threshold, or the maximum voltage difference is higher than the second preset voltage difference, or the target battery cell temperature is lower than the minimum allowable temperature, or the target battery cell temperature is higher than the maximum battery cell temperature, stop executing the step of selecting the corresponding balancing strategy.

[0025] In one embodiment, each of the single cells is further connected to an external balancing circuit, and after the step of collecting the cell voltages and cell temperatures corresponding to each of the single cells, the step further includes:

[0026] Displaying the voltage of each battery cell and the temperature of each battery cell to the user;

[0027] Based on a manual control instruction triggered by a user, a corresponding one of the active balancing circuit, the passive balancing circuit, or the external balancing circuit is turned on to perform balancing control on each of the single cells.

[0028] In addition, to achieve the above-mentioned purpose, the present application also provides a battery balancing control device, the battery balancing control device comprising:

[0029] The cell parameter acquisition module is used to collect the cell voltage and cell temperature corresponding to each single cell in each battery pack connected in series;

[0030] A balanced start-stop control module, used to determine whether it is necessary to perform balanced control on each of the single cells based on the voltage of each cell;

[0031] The balancing mode selection module is used to start a corresponding one of the active balancing circuits or passive balancing circuits connected to each of the single cells to perform balancing control on each of the single cells based on the voltage of each cell and the temperature of each cell when it is determined that balancing control needs to be performed on each of the single cells.

[0032] In addition, to achieve the above-mentioned purpose, the present application also provides a battery balancing control device, which includes: a memory, a processor, and a battery balancing control program stored in the memory and executable on the processor, wherein the battery balancing control program is configured to implement the steps of the battery balancing control method described above.

[0033] In addition, to achieve the above-mentioned purpose, the present application also provides a storage medium, which is a computer-readable storage medium, and a battery balancing control program is stored on the computer-readable storage medium. When the battery balancing control program is executed by a processor, the steps of the battery balancing control method described above are implemented.

[0034] The present application provides a battery balancing control method, device, equipment and storage medium, the steps of the battery balancing control method include: collecting the cell voltages and cell temperatures corresponding to each of the single cells; judging whether it is necessary to perform balancing control on each of the single cells based on the cell voltages; when judging that it is necessary to perform balancing control on each of the single cells, based on the cell voltages and cell temperatures, turning on the active balancing circuit or the passive balancing circuit to perform balancing control on each of the single cells. By obtaining the cell voltages and cell temperatures of each of the single cells in a plurality of battery packs connected in series, it is judged whether it is necessary to perform balancing control on each of the single cells, and the specific method of currently performing balancing control on each of the single cells is selected according to the cell voltages and cell temperatures, so that the balancing control method can be adaptively adjusted in the case of temperature changes to meet the different requirements corresponding to balancing control in different scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0036] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0037] Figure 1A flowchart of the first embodiment of the battery balancing control method of the present application is provided;

[0038] Figure 2 A schematic diagram of the structure of a battery balancing system provided in this application;

[0039] Figure 3 A flowchart of the second embodiment of the battery balancing control method of the present application is provided;

[0040] Figure 4 A flowchart of the third embodiment of the battery balancing control method of the present application is provided;

[0041] Figure 5 This is a schematic diagram of the module structure of the battery balancing control device according to an embodiment of the present application;

[0042] Figure 6 This is a schematic diagram of the structure of a battery balancing control device according to an embodiment of the present application.

[0043] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0044] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0045] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0046] This application proposes a first embodiment of a battery balancing control method, please refer to Figure 1 The battery balancing control method is applied to a battery balancing system, wherein the battery balancing system comprises a plurality of battery packs connected in series, each of the battery packs comprises a plurality of single cells, each of the single cells is connected to an active balancing circuit and a passive balancing circuit, and the steps of the battery balancing control method include:

[0047] Step S10, collecting the cell voltage and cell temperature corresponding to each of the single cells;

[0048] It should be understood that in this embodiment, the execution subject may be a battery balancing control device, or a battery balancing control device with data processing, network communication and program running functions, etc. The battery balancing control device or device is located in the battery balancing system, and this embodiment does not specifically limit this. The following takes the brake wheel speed control device as the execution subject as an example to illustrate this embodiment and the following embodiments.

[0049] It should be noted that if Figure 2As shown, in this embodiment, in the battery balancing system, each battery pack is connected in series with the same polarity direction, each battery pack contains a plurality of single cells of the same number, each single cell is also in series with each other and has the same polarity direction. The battery balancing system also includes an active balancing circuit and a passive balancing circuit, and the active balancing circuit and the passive balancing circuit are connected to each single cell. The controller in the figure can be an execution subject, which can be specifically composed of a master controller and a plurality of slave controllers. When the execution subject controls the active balancing circuit to be turned on, the corresponding two single cells in the battery pack can be connected in parallel by closing the corresponding switch device in the active balancing circuit, so that the electric energy is transferred from the single cell with a higher output voltage to the single cell with a lower output voltage, thereby realizing active balancing control of each single cell. As a special case, the single cell with a higher output voltage and the single cell with a lower output voltage are respectively in different battery packs. At this time, multiple isolated DCDC modules can be controlled to work, and the corresponding switch devices can be closed to connect the single cells with a higher output voltage and the single cells with a lower output voltage in different battery packs in parallel, thereby realizing active balancing control across battery packs. The passive balancing circuit includes several balancing resistors, each of which is connected in parallel with each single cell through a corresponding switch device. When the voltage of a single cell is high, the corresponding switch device can be closed, so that the balancing resistor consumes the electric energy stored in the single cell, thereby realizing passive balancing control. The above-mentioned active balancing circuit and passive balancing circuit are both controlled by the main control module. When the number of battery packs is large, multiple slave control modules can be set between the main control module and the active balancing circuit and the passive balancing circuit for master-slave distributed control.

[0050] It is easy to understand that in this embodiment, each single cell is also connected to a battery management system (BMS), and the execution body of this embodiment is also connected to the BMS ( Figure 2 The above connection relationship with the BMS is not drawn in the figure), so the cell data of each single cell can be collected through the BMS, such as cell voltage, cell temperature, smoke concentration, etc. The execution subject can mainly collect the cell voltage and cell temperature of each single cell through the BMS.

[0051] Step S20, judging whether it is necessary to perform balancing control on each of the single cells based on the voltage of each of the cells;

[0052] It is easy to understand that balancing control is mainly used to prevent the output voltage difference between multiple battery packs or single cells connected in series from being too large due to the large difference in internal resistance, thereby causing overcharging or over-discharging. In this embodiment, it can be judged whether there is a situation where the cell voltage difference is too large based on the collected cell voltages corresponding to each single cell. It can also be understood that it can be judged whether it is necessary to perform balancing control on each single cell based on whether the maximum voltage difference between the cell voltages exceeds the pre-set voltage difference threshold indicating that it will not cause serious overcharging or over-discharging.

[0053] Step S30 , when it is determined that the battery cells need to be balanced, based on the battery cell voltages and the battery cell temperatures, a corresponding one of the active balancing circuit or the passive balancing circuit is turned on to perform balanced control on the battery cells.

[0054] It should be noted that, in the present embodiment, when the maximum voltage difference between the voltages of each battery cell currently exceeds the voltage difference threshold, that is, when it is determined that each battery cell needs to be balanced, a specific automatic balancing strategy can be adaptively selected based on the specific values ​​of the voltages of each battery cell and the specific values ​​of the temperatures of each battery cell. The automatic balancing strategy includes at least an active balancing strategy and a passive balancing strategy. When the active balancing circuit is turned on, it can be considered that the active balancing strategy is selected to balance the individual cells, that is, the individual cells with the maximum cell voltage are connected in parallel with the individual cells with the minimum cell voltage through the switch devices in the active balancing circuit or the combination of the switch devices and the isolated DCDC module, so that the individual cells with the maximum cell voltage are supplemented with the individual cells with the minimum cell voltage, thereby achieving balanced control between the individual cells, but this method easily causes the cell temperature of the individual cells to rise sharply, which may pose certain safety hazards; when the passive balancing circuit is turned on, it can be considered that the passive balancing strategy is selected to balance the individual cells, that is, by closing the corresponding number of switch devices in the passive balancing circuit, the balancing resistors connected in series with the individual cells with the maximum cell voltage are connected in parallel, so that the excessive electric energy of the corresponding individual cells is consumed by the balancing resistors, thereby achieving balanced control between the individual cells, wherein the number of balancing resistors connected in parallel with the corresponding individual cells can be selected according to the current cell temperature, and the higher the cell temperature, the more balancing resistors are connected in parallel with it.

[0055] It is worth noting that in this embodiment, when the passive balancing strategy is adopted, the cell capacity of each single cell can be obtained by combining the mapping relationship between the cell capacity and the cell voltage calculated historically with the cell voltage of each single cell, and then the maximum capacity difference can be obtained by the maximum cell capacity and the minimum cell capacity. At the same time, the current required balancing current can be read through the maximum voltage difference and the cell temperature through the pre-set mapping relationship table of voltage difference, temperature and balancing current, and then the resistance value of the balancing resistor to be connected can be obtained through the balancing current and the maximum voltage difference, that is, the number of balancing resistors to be connected can be obtained. After obtaining the balancing current and the maximum capacity difference, the balancing time required for this passive balancing control can be calculated, and the passive balancing strategy can be limited by the calculated balancing time, so that the safety of the passive balancing strategy can be further improved.

[0056] The present application provides a battery balancing control method, the steps of which include: collecting the cell voltages and cell temperatures corresponding to each of the single cells; judging whether it is necessary to perform balancing control on each of the single cells based on the cell voltages; when judging that it is necessary to perform balancing control on each of the single cells, based on the cell voltages and cell temperatures, turning on the active balancing circuit or the passive balancing circuit to perform balancing control on each of the single cells. By obtaining the cell voltages and cell temperatures of each of the single cells in a plurality of battery packs connected in series, it is judged whether it is necessary to perform balancing control on each of the single cells, and the specific method of currently performing balancing control on each of the single cells is selected based on the cell voltages and cell temperatures, so that the balancing control method can be adaptively adjusted in the case of temperature changes to meet the different requirements corresponding to balancing control in different scenarios.

[0057] Based on the first embodiment of the battery balancing control method of the present application, in the second embodiment of the battery balancing control method of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 3 The step of judging whether it is necessary to perform balancing control on each of the battery cells based on the voltage of each of the battery cells comprises:

[0058] Step S21, screening out a maximum cell voltage and a minimum cell voltage from the cell voltages, and obtaining a maximum voltage difference between the maximum cell voltage and the minimum cell voltage;

[0059] It is easy to understand that when obtaining the voltage of each cell, the maximum value of the cell voltage, i.e., the maximum cell voltage, can be screened out, and the minimum value of the cell voltage, i.e., the minimum cell voltage, can also be screened out. By performing a difference process between the maximum cell voltage and the minimum cell voltage and taking the absolute value, the maximum voltage difference between each single cell can be obtained.

[0060] Step S22, when the maximum voltage difference is greater than a preset voltage difference threshold, determining that balancing control needs to be performed on each of the single cells;

[0061] Step S23, or, when the maximum voltage difference is not greater than the voltage difference threshold, it is determined that there is no need to perform balancing control on each of the single cells.

[0062] It is easy to understand that in the present embodiment, the voltage difference threshold refers to a pre-set voltage difference used to indicate the voltage difference that may cause overcharge or over-discharge of each battery cell during the charging and discharging process. Therefore, when the maximum voltage difference between each single cell is greater than the voltage difference threshold, each single cell is very likely to be overcharged or over-discharged during charging and discharging, and at this time, each single cell needs to be balanced; on the contrary, if the maximum voltage difference does not exceed the pre-set voltage difference threshold, each single cell will basically not be overcharged or over-discharged during charging and discharging, and at this time, each single cell does not need to be balanced.

[0063] Further, in this embodiment, when it is determined that each of the single cells needs to be balanced, based on the voltage of each cell and the temperature of each cell, the step of starting a corresponding one of the active balancing circuit or the passive balancing circuit to perform balanced control on each of the single cells includes:

[0064] Step S31, when it is determined that each of the single cells needs to be balanced, select a corresponding balancing strategy based on the voltage of each cell and the temperature of each cell;

[0065] It is easy to understand that in the present embodiment, when it is determined that each battery cell may be at risk of overcharging or over-discharging if charged or discharged in the current state, that is, when it is determined that each battery cell needs to be balanced controlled, a corresponding balancing strategy can be selected based on the maximum voltage difference obtained through the voltage of each battery cell and the battery cell temperature of the battery cell that needs to be balanced controlled, so as to cope with different scenarios in which the difference between the voltages of each battery cell is too large or too small and in which the battery cell temperature is too high or too low.

[0066] Step S32, when the balancing strategy is an active balancing strategy, turning on the active balancing circuit to perform active balancing control on each of the single cells;

[0067] Step S33, or, when the balancing strategy is a passive balancing strategy, turning on the passive balancing circuit to perform passive balancing control on each of the single cells.

[0068] It is easy to understand that in this embodiment, when the currently selected balancing strategy is determined to be an active balancing strategy through the voltage of each battery cell and the temperature of each battery cell, the corresponding active balancing circuit is turned on, and the corresponding single battery cells that need voltage balancing are sequentially connected in parallel, so that the electric energy in each single battery cell is balanced, so as to achieve the control effect of active balancing;

[0069] When it is determined through the voltages and temperatures of each battery cell that the currently selected balancing strategy is a passive balancing strategy, the corresponding passive balancing circuit is turned on, and the corresponding single battery cells that need voltage balancing are connected in parallel with multiple balancing resistors in the passive balancing circuit. The number of parallel balancing resistors is determined by the battery cell temperature of the current single battery cell, so that the electric energy in each single battery cell is more evenly distributed, that is, the voltage is balanced, so as to achieve the control effect of passive balancing.

[0070] Further, in this embodiment, when it is determined that the balancing control needs to be performed on each of the single cells, the step of selecting a corresponding balancing strategy based on the voltage of each cell and the temperature of each cell includes:

[0071] Step S311, obtaining a maximum voltage difference between a maximum cell voltage and a minimum cell voltage through each of the cell voltages, and obtaining a target cell temperature corresponding to a single cell of the maximum cell voltage through each of the cell temperatures;

[0072] Step S312: selecting the corresponding balancing strategy based on the target battery cell temperature and the maximum voltage difference.

[0073] It should be noted that, in this embodiment, the conditions for selecting various balancing strategies are actually the maximum difference between the voltages of the cells and the cell temperature corresponding to the single cell that needs to be balanced, that is, the maximum voltage difference and the target cell temperature mentioned above. Among them, the passive balancing strategy is generally applicable to scenes with higher temperatures or smaller voltage differences, while the active balancing strategy is generally applicable to scenes with lower temperatures or larger voltage differences.

[0074] Further, in this embodiment, the step of selecting the corresponding balancing strategy based on the target battery cell temperature and the maximum voltage difference includes:

[0075] Step S3121, when the maximum voltage difference is between the voltage difference threshold and the first preset voltage difference and the target cell temperature is between the minimum allowable temperature and the maximum allowable temperature, the balancing strategy is selected as the passive balancing strategy, and the first preset voltage difference is greater than the voltage difference threshold;

[0076] It should be noted that the voltage difference threshold refers to the minimum voltage difference for turning on the balancing control, and the first preset voltage difference refers to the voltage difference corresponding to the case where the balancing current required by the single cell is theoretically small, which should be slightly higher than the voltage difference threshold and should not be too large. The minimum allowable temperature refers to the lowest temperature corresponding to the normal operation of the single cell, and the maximum allowable temperature refers to the highest temperature corresponding to the normal operation of the single cell. In this embodiment, when the cell temperature of the single cell that needs to be balanced is between the safe minimum allowable temperature and the maximum allowable temperature (indicating that the current cell temperature is not abnormally too large or too small), and the maximum voltage difference between each single cell is between the voltage difference threshold and the first preset voltage difference (indicating that each single cell is not in urgent need of balancing control), the passive balancing strategy can be selected as the current best balancing strategy to achieve safe balancing.

[0077] Step S3122, or, when the maximum voltage difference is between the first preset voltage difference and the second preset voltage difference and the target cell temperature is between the minimum allowable temperature and a preset cell temperature threshold, the balancing strategy is selected as the active balancing strategy, the second preset voltage difference is greater than the first preset voltage difference, and the cell temperature threshold is between the maximum allowable temperature and the minimum allowable temperature;

[0078] It should be noted that the second preset voltage difference refers to the maximum allowable voltage difference corresponding to the case where the balancing current required by the single cell is theoretically larger, which is higher than the first preset voltage difference. The cell temperature threshold refers to the set temperature used to distinguish whether the current cell temperature has an overheating risk, which is between the maximum allowable temperature and the minimum allowable temperature, and is biased towards the maximum allowable temperature. In this embodiment, when the cell temperature of the single cell that needs to be balanced is between the minimum allowable temperature and the cell temperature threshold (indicating that there is no overheating risk at present), and the maximum voltage difference between each single cell is between the first preset voltage difference and the second preset voltage difference (indicating that each single cell is in urgent need of balancing control at present), the active balancing strategy can be selected as the current best balancing strategy to achieve rapid balancing.

[0079] Step S3123, or, when the maximum voltage difference is between the first preset voltage difference and the second preset voltage difference and the target battery cell temperature is between the battery cell temperature threshold and the maximum allowable temperature, the balancing strategy is selected as the passive balancing strategy.

[0080] It should be noted that, in the present embodiment, when the cell temperature of the single cell that needs to be balanced is between the cell temperature threshold and the maximum allowable temperature (indicating that there is a risk of overheating at present), and the maximum voltage difference between the single cells is between the first preset voltage difference and the second preset voltage difference (indicating that each single cell urgently needs to be balanced), a passive balancing strategy can be selected as the current optimal balancing strategy to perform balancing control as quickly as possible based on safety and speed considerations.

[0081] It is worth noting that in this embodiment, the magnitude of the balancing current can be controlled by setting multiple cell temperature thresholds, that is, the power generated by each single cell during the balancing control process can be controlled, thereby avoiding the occurrence of overheating caused by continuous temperature rise of each battery cell and ensuring safety. Based on a similar principle, multiple preset voltage differences can also be set to control the magnitude of the balancing current and control the power generated by each single cell during the balancing control process. This method can also avoid the occurrence of overheating caused by continuous temperature rise of each battery cell.

[0082] Based on the first embodiment and / or the second embodiment of the battery balancing control method of the present application, in the third embodiment of the battery balancing control method of the present application, please refer to Figure 4 , the step of selecting the corresponding balancing strategy based on the target battery cell temperature and the maximum voltage difference further includes:

[0083] Step S3124, when the maximum voltage difference is lower than the voltage difference threshold, or the maximum voltage difference is higher than the second preset voltage difference, or the target battery cell temperature is lower than the minimum allowable temperature, or the target battery cell temperature is higher than the maximum battery cell temperature, stop executing the step of selecting the corresponding balancing strategy.

[0084] It should be noted that, in this embodiment, if the maximum voltage difference of each single cell is lower than the voltage difference threshold, it means that there is no need for balancing control; if the maximum voltage difference of each single cell is higher than the second preset voltage difference, it means that there is a single cell voltage abnormality, and balancing control cannot be performed safely at this time; if the target cell temperature corresponding to the single cell that needs to be balanced is lower than the minimum allowable temperature, the charging and discharging operation cannot be performed normally, and the balancing control cannot be performed normally; if the target cell temperature corresponding to the single cell that needs to be balanced is higher than the maximum allowable temperature, continuing the balancing control may cause overheating and cause a fire, and the balancing control cannot be performed normally. In the above-mentioned cases, the operation of selecting the corresponding balancing strategy will not be executed, and balancing control is prohibited, and even the charging or discharging of each single cell is prohibited.

[0085] Furthermore, in this embodiment, each of the single cells is also connected to an external balancing circuit, and after the step of collecting the cell voltages and cell temperatures corresponding to each of the single cells, the method further includes:

[0086] Step S40, displaying the voltage of each battery cell and the temperature of each battery cell to the user;

[0087] Step S50: based on the manual control instruction triggered by the user, start a corresponding one of the active balancing circuit, the passive balancing circuit or the external balancing circuit to perform balancing control on each of the single cells.

[0088] It is easy to understand that each single cell is also connected to an external balancing circuit ( Figure 2 (not shown), the external balancing circuit can be composed of an external power supply, a balancing resistor and a plurality of switching devices, and each single cell can be directly connected to the external power supply for charging or connected to the balancing resistor for discharging by controlling the on-off state of the corresponding switching device, thereby realizing external balancing control. In this embodiment, the execution subject can also display the collected cell voltages and cell temperatures to the user through a display device, that is, to the current operator. The user or operator can perform manual operations based on the observed digitized cell voltages and cell temperatures to trigger the generation of corresponding manual control instructions. Upon receiving the manual control instructions, the execution subject will force the current balancing strategy to be switched to the balancing strategy required by the user. Among them, the balancing strategy may include an active balancing strategy, a passive balancing strategy and an external balancing strategy. When the active balancing strategy is adopted, the active balancing circuit is turned on to connect the single cell with the largest cell voltage in parallel with the single cell with the smallest cell voltage, so that the single cell with the largest cell voltage charges the single cell with the smallest cell voltage, so as to achieve active balancing control; when the passive balancing strategy is adopted, the passive balancing circuit is turned on to connect the single cell with the largest cell voltage with a number of balancing resistors corresponding to the number of cell temperatures, so that the single cell with the largest cell voltage is discharged, so as to achieve passive balancing control; when the external balancing strategy is adopted, the external balancing circuit is turned on to connect the single cell with the largest cell voltage with a number of balancing resistors corresponding to the number of cell temperatures for discharge, and the single cell with the smallest cell voltage is connected to an external power supply for charging, so as to achieve external balancing control.

[0089] In addition, this application also proposes a battery balancing control device, please refer to Figure 5 , the battery balancing control device comprises:

[0090] The cell parameter acquisition module 10 is used to acquire the cell voltage and cell temperature corresponding to each single cell in each battery pack connected in series;

[0091] A balanced start-stop control module 20 is used to determine whether it is necessary to perform balanced control on each of the single cells based on the voltage of each cell;

[0092] The balancing mode selection module 30 is used to start a corresponding one of the active balancing circuits or passive balancing circuits connected to each of the single cells to perform balancing control on each of the single cells based on the voltage of each cell and the temperature of each cell when it is determined that balancing control needs to be performed on each of the single cells.

[0093] The battery balancing control device provided in the embodiment of the present application adopts the battery balancing control method in the above embodiment, which can solve the technical problem of how to select the corresponding balancing method according to different battery cell temperatures and battery cell voltages to effectively maintain the balance between the individual battery cells in multiple series-connected battery packs. Compared with the prior art, the beneficial effects of the battery balancing control device provided in the embodiment of the present application are the same as the beneficial effects of the battery balancing control method provided in the above embodiment, and the other technical features in the battery balancing control device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0094] The present application provides a battery balancing control device, the battery balancing control device comprising: at least one processor; and a memory connected to the at least one processor in communication; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the battery balancing control method in the above-mentioned embodiment 1.

[0095] Reference below Figure 6 , which shows a schematic diagram of the structure of a battery balancing control device suitable for implementing the embodiment of the present application. The battery balancing control device in the embodiment of the present application may include but is not limited to a fixed terminal such as a vehicle-mounted terminal. Figure 6 The battery balancing control device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0096] like Figure 6As shown, the battery balancing control device may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the battery balancing control device are also stored. The processing device 1001, ROM1002, and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 may allow the battery balancing control device to communicate with other devices wirelessly or by wire to exchange data. Although the figure shows a battery balancing control device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have alternatively.

[0097] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0098] The battery balancing control device provided by the present application adopts the battery balancing control method in the above embodiment, which can solve the technical problem of how to select the corresponding balancing method according to different battery cell temperatures and battery cell voltages to effectively maintain the balance between the individual battery cells in multiple series-connected battery packs. Compared with the prior art, the beneficial effects of the battery balancing control device provided by the present application are the same as the beneficial effects of the battery balancing control method provided by the above embodiment, and the other technical features in the battery balancing control device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0099] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0100] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0101] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the battery balancing control method in the above-mentioned embodiment.

[0102] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0103] The computer-readable storage medium may be included in the battery balancing control device; or may exist independently without being assembled into the battery balancing control device.

[0104] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by the battery balancing control device, the battery balancing control device: collects the cell voltages and cell temperatures corresponding to the individual cells; based on the cell voltages, determines whether it is necessary to perform balancing control on the individual cells; when it is determined that it is necessary to perform balancing control on the individual cells, based on the cell voltages and cell temperatures, starts the corresponding one of the active balancing circuit or the passive balancing circuit to perform balancing control on the individual cells.

[0105] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0106] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0107] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0108] The readable storage medium provided by the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned battery balancing control method, and can solve the technical problem of how to select corresponding balancing methods according to different battery cell temperatures and battery cell voltages to effectively maintain balance between each single battery cell in a plurality of series-connected battery packs. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the present application are the same as the beneficial effects of the battery balancing control method provided by the above-mentioned embodiment, and will not be repeated here.

[0109] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent processing scope of the present application.

Claims

1. A battery balancing control method, characterized in that: Applied to a battery balancing system, the battery balancing system includes a plurality of battery packs connected in series, each of the battery packs includes a plurality of single cells, each of the single cells is connected to an active balancing circuit and a passive balancing circuit, and the steps of the battery balancing control method include: Collecting the voltage of each battery cell and the temperature of each battery cell corresponding to each of the single battery cells; Based on the voltage of each battery cell, determining whether it is necessary to perform balancing control on each of the single battery cells; When it is determined that the battery cells need to be balanced, based on the battery cell voltages and the battery cell temperatures, a corresponding one of the active balancing circuit or the passive balancing circuit is turned on to perform balanced control on the battery cells.

2. The battery balancing control method according to claim 1, characterized in that: The step of judging whether it is necessary to perform balancing control on each of the single cells based on the voltage of each of the cells comprises: Screening out a maximum cell voltage and a minimum cell voltage from the cell voltages, and obtaining a maximum voltage difference between the maximum cell voltage and the minimum cell voltage; When the maximum voltage difference is greater than a preset voltage difference threshold, determining that each of the single cells needs to be balanced; Or, when the maximum voltage difference is not greater than the voltage difference threshold, it is determined that there is no need to perform balancing control on each of the single battery cells.

3. The battery balancing control method according to claim 1, wherein: When it is determined that each of the single cells needs to be balanced, the step of starting a corresponding one of the active balancing circuit or the passive balancing circuit to perform balanced control on each of the single cells based on the voltage of each cell and the temperature of each cell includes: When it is determined that each of the single cells needs to be balanced, a corresponding balancing strategy is selected based on the voltage of each cell and the temperature of each cell; When the balancing strategy is an active balancing strategy, turning on the active balancing circuit to perform active balancing control on each of the single cells; Or, when the balancing strategy is a passive balancing strategy, the passive balancing circuit is turned on to perform passive balancing control on each of the single cells.

4. The battery balancing control method according to claim 3, characterized in that: When it is determined that the balancing control needs to be performed on each of the single cells, the step of selecting a corresponding balancing strategy based on the voltage of each cell and the temperature of each cell includes: Acquire a maximum voltage difference between a maximum cell voltage and a minimum cell voltage through each of the cell voltages, and acquire a target cell temperature corresponding to a single cell of the maximum cell voltage through each of the cell temperatures; Based on the target battery cell temperature and the maximum voltage difference, the corresponding balancing strategy is selected.

5. The battery balancing control method according to claim 4, characterized in that: The step of selecting the corresponding balancing strategy based on the target battery cell temperature and the maximum voltage difference includes: When the maximum voltage difference is between the voltage difference threshold and the first preset voltage difference and the target cell temperature is between the minimum allowable temperature and the maximum allowable temperature, the balancing strategy is selected as the passive balancing strategy, and the first preset voltage difference is greater than the voltage difference threshold; Or, when the maximum voltage difference is between the first preset voltage difference and the second preset voltage difference and the target cell temperature is between the minimum allowable temperature and a preset cell temperature threshold, the balancing strategy is selected as the active balancing strategy, the second preset voltage difference is greater than the first preset voltage difference, and the cell temperature threshold is between the maximum allowable temperature and the minimum allowable temperature; Or, when the maximum voltage difference is between the first preset voltage difference and the second preset voltage difference and the target battery cell temperature is between the battery cell temperature threshold and the maximum allowable temperature, the balancing strategy is selected as the passive balancing strategy.

6. The battery balancing control method according to claim 5, characterized in that: The step of selecting the corresponding balancing strategy based on the target battery cell temperature and the maximum voltage difference further includes: When the maximum voltage difference is lower than the voltage difference threshold, or the maximum voltage difference is higher than the second preset voltage difference, or the target battery cell temperature is lower than the minimum allowable temperature, or the target battery cell temperature is higher than the maximum battery cell temperature, stop executing the step of selecting the corresponding balancing strategy.

7. The battery balancing control method according to claim 1, wherein: Each of the single cells is also connected to an external balancing circuit. After the step of collecting the cell voltages and cell temperatures corresponding to each of the single cells, the method further includes: Displaying the voltage of each battery cell and the temperature of each battery cell to the user; Based on a manual control instruction triggered by a user, a corresponding one of the active balancing circuit, the passive balancing circuit, or the external balancing circuit is turned on to perform balancing control on each of the single cells.

8. A battery balancing control device, characterized in that: The battery balancing control device comprises: The cell parameter acquisition module is used to collect the cell voltage and cell temperature corresponding to each single cell in each battery pack connected in series; A balanced start-stop control module, used to determine whether it is necessary to perform balanced control on each of the single cells based on the voltage of each cell; The balancing mode selection module is used to start a corresponding one of the active balancing circuits or passive balancing circuits connected to each of the single cells to perform balancing control on each of the single cells based on the voltage of each cell and the temperature of each cell when it is determined that balancing control needs to be performed on each of the single cells.

9. A battery balancing control device, characterized in that: The battery balancing control device comprises: a memory, a processor, and a battery balancing control program stored in the memory and executable on the processor, wherein the battery balancing control program is configured to implement the steps of the battery balancing control method according to any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, on which a battery balancing control program is stored. When the battery balancing control program is executed by a processor, the steps of the battery balancing control method according to any one of claims 1 to 7 are implemented.

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