Battery equalization method and device, controller and electric equipment

Abstract

The invention provides a battery equalization method and device, a controller and electric equipment, and the method comprises the steps: determining a target equalization mode from a plurality of equalization modes based on the state information of a battery, the state information of the battery comprises the state information of the battery in the charging process and / or after the charging is completed, and the target equalization mode is used for balancing the state information of the battery based on the target equalization mode; according to the invention, the target equalization mode can be selected from a plurality of equalization modes without being limited to one equalization mode, and the flexibility of battery equalization and the precision of battery equalization can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery management, and in particular to a battery balancing method, device, controller and electrical equipment. Background Art

[0002] The voltage of a single battery cell (such as a lithium-ion battery cell) is only a few volts. Whether used as a power source for electric vehicles or in backup power applications, the electrical characteristics of a single power battery cell cannot meet the voltage and current requirements of the load under operating conditions. Therefore, to increase the voltage of the power battery, several single cells can be connected in series to form a group.

[0003] To prevent damage to the batteries caused by overcharging or over-discharging during use, a commonly used charge and discharge strategy for series battery packs is to stop charging when the highest cell voltage in the pack exceeds a preset upper limit, and to stop discharging when the lowest cell voltage in the pack falls below a preset lower limit. However, as the battery pack is used, the self-discharge rate of each cell varies, which will lead to different capacities of each cell in the pack, thus affecting the full capacity of the battery pack. Therefore, balancing technology is needed to adjust the capacity of each cell so that the voltage, capacity, and status of each cell in the battery pack are relatively consistent, thereby improving the performance and life of the entire battery pack. Summary of the Invention

[0004] The present invention provides a battery balancing method, device, controller and electrical equipment for selecting a balancing mode from multiple balancing modes to balance batteries, thereby improving the flexibility of battery balancing.

[0005] In a first aspect, the present invention provides a battery balancing method, the method comprising:

[0006] Determining a target balancing mode from a plurality of balancing modes based on battery status information; wherein the battery status information includes battery status information during and / or after charging;

[0007] The battery is balanced based on the target balancing mode.

[0008] Optionally, the multiple balancing modes include two or more of the following combinations: top static balancing, top dynamic balancing, middle balancing, bottom balancing and cloud-calibrated balancing.

[0009] Optionally, the battery status information includes: the charging voltage of each single cell in the battery and the open circuit voltage of each single cell in the battery; the battery status information satisfies the execution condition of top static balancing if:

[0010] The charging voltage of the target single cell in the battery status information reaches the full charge condition, and the maximum open circuit voltage among the open circuit voltages of the single cells in the battery status information is greater than the first preset open circuit voltage; the target single cell is the single cell with the highest charging voltage.

[0011] Optionally, determining a target balancing mode from a plurality of balancing modes based on battery status information includes:

[0012] The target balancing mode is determined based on the battery status information and the execution conditions of each balancing mode currently in use; different balancing modes correspond to different execution conditions; the target balancing mode is the balancing mode determined from each balancing mode currently in use when the battery status information meets the corresponding execution conditions.

[0013] Optionally, if top static balancing exists among the balancing modes currently in use, determining the target balancing mode according to the battery status information and the execution conditions of the balancing modes currently in use includes:

[0014] After battery charging is completed, if it is determined that the battery has a balancing requirement, and the charging voltage of the target single cell in the battery status information reaches the full charging condition, and the maximum open-circuit voltage among the open-circuit voltages of the individual single cells in the battery status information is greater than a first preset open-circuit voltage, then top static balancing is determined as the target balancing mode; the target single cell is the single cell with the highest charging voltage.

[0015] Optionally, determining whether the battery needs to be balanced includes:

[0016] When it is determined that the difference between the maximum open circuit voltage and the minimum open circuit voltage among the open circuit voltages corresponding to the individual battery cells is greater than a first preset difference, it is determined that the battery has a balancing requirement.

[0017] Optionally, balancing the battery based on the target balancing mode includes:

[0018] For each single cell, determining the corresponding remaining capacity according to the open circuit voltage of the single cell;

[0019] For each single cell in the battery except a first reference single cell, determining an equalization value for each single cell according to the remaining capacity of the single cell and the remaining capacity of the first reference single cell; wherein the first reference single cell is the single cell with the smallest open circuit voltage among all the single cells when fully charged;

[0020] The single battery cells are balanced according to the balance values of the single battery cells.

[0021] Optionally, determining the corresponding remaining capacity according to the open circuit voltage of the single battery cell includes:

[0022] The remaining capacity corresponding to the open circuit voltage of the single battery cell is determined according to a preset corresponding relationship; the preset corresponding relationship represents the relationship between the remaining capacity and the open circuit voltage.

[0023] Optionally, if top dynamic balancing is present in each of the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of each of the currently used balancing modes further includes:

[0024] If the maximum open-circuit voltage among the open-circuit voltages of the individual battery cells in the battery status information is less than or equal to the first preset open-circuit voltage, and it is determined that the stored first balancing time is greater than 0, top dynamic balancing is determined as the target balancing mode;

[0025] The first balancing time is calculated and stored after the battery is fully charged and the battery status information satisfies the execution condition of the top dynamic balancing.

[0026] Optionally, the battery status information satisfies the execution conditions of top dynamic balancing:

[0027] The charging voltage of the target single cell in the battery status information reaches the full charging condition and the top static balancing is not started for more than a first preset time.

[0028] Optionally, the method further includes:

[0029] Obtaining the charging voltage of each single cell when the battery reaches a full charge condition during the charging process, and for any single cell in the battery except the second reference single cell, when the difference between the charging voltage corresponding to the single cell and the charging voltage of the second reference single cell is greater than a second preset difference, storing the identifier of the single cell and the corresponding first balancing time;

[0030] The second reference single cell is a cell with the smallest charging voltage among all the single cells.

[0031] Optionally, the method further includes:

[0032] After the top dynamic balancing is determined as the target balancing mode and the battery is balanced, the stored first balancing duration is reset to 0.

[0033] Optionally, if mid-segment balancing still exists in the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes further includes:

[0034] When the stored first balancing time length is not greater than 0 and the stored second balancing time length is greater than 0, determining the mid-segment balancing as the target balancing mode;

[0035] The second balancing time is calculated and stored when the battery status information meets the execution condition of mid-segment balancing.

[0036] Optionally, the battery status information satisfies the execution conditions of mid-segment balancing:

[0037] During the charging process, the inflection point capacities of at least two single cells detected are valid, and top static balancing or top dynamic balancing is not started for more than a second preset time period;

[0038] The second preset duration is greater than the first preset duration.

[0039] Optionally, the method further includes:

[0040] For any single cell in the battery except a third reference single cell, determining a relative capacity difference of the single cell based on the inflection point capacity of the single cell detected during charging and the inflection point capacity of the third reference single cell; the third reference single cell is the single cell corresponding to the maximum inflection point capacity among all inflection point capacities;

[0041] A second balancing time duration corresponding to the single battery cell is determined according to the relative capacity difference, and the identifier of the single battery cell and the corresponding second balancing time duration are stored.

[0042] Optionally, the method further includes:

[0043] Obtaining the inflection point capacity and inflection point capacity confidence corresponding to at least two single battery cells detected during the charging process;

[0044] When the inflection point capacity confidence level is greater than a preset confidence level, it is determined that the inflection point capacity corresponding to the inflection point capacity confidence level is valid.

[0045] Optionally, the method further includes:

[0046] The mid-segment balancing is determined as the target balancing mode, and after the battery is balanced, the stored second balancing duration is reset to 0.

[0047] Optionally, if mid-segment balancing exists but top dynamic balancing does not exist among the currently used balancing modes, determining the target balancing mode according to battery status information and execution conditions of the currently used balancing modes further includes:

[0048] When the maximum open-circuit voltage among the open-circuit voltages of the individual battery cells in the battery status information is less than or equal to the first preset open-circuit voltage, and it is determined that the stored second balancing time is greater than 0, mid-segment balancing is determined as the target balancing mode;

[0049] The second balancing time is calculated and stored when the battery status information meets the execution condition of mid-segment balancing.

[0050] Optionally, the battery status information satisfies the execution conditions of mid-segment balancing:

[0051] During the charging process, the inflection point capacities of at least two single battery cells detected are valid, and top static balancing is not enabled for more than a second preset time period.

[0052] Optionally, if bottom balancing still exists in the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes further includes:

[0053] When the stored second balancing time is not greater than 0, if the minimum open-circuit voltage among the open-circuit voltages of each single cell is less than the second preset open-circuit voltage and none of the top static balancing, top dynamic balancing and middle balancing is turned on for more than the third preset time, the bottom balancing is determined as the target balancing mode; the third preset time is greater than the second preset time; the second preset open-circuit voltage is less than the first preset open-circuit voltage.

[0054] Optionally, balancing the battery based on the target balancing mode includes:

[0055] For any single cell in the battery except the fourth reference single cell, when the difference between the open circuit voltage corresponding to the any single cell and the open circuit voltage of the fourth reference single cell is greater than a third preset difference, determining the corresponding remaining capacity according to the open circuit voltage of the any single cell;

[0056] Determining the equilibrium value of each single cell according to the remaining capacity of each single cell and the remaining capacity of the fourth reference single cell; the fourth reference single cell is the single cell with the smallest open circuit voltage among all the single cells in the current state;

[0057] The single battery cells are balanced according to the balance values of the single battery cells.

[0058] Optionally, if bottom balancing exists but mid-balancing does not exist among the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes further includes:

[0059] When the stored first balancing time is not greater than 0, if the minimum open-circuit voltage among the open-circuit voltages of each single cell is less than the second preset open-circuit voltage and the top static balancing or the top dynamic balancing is not turned on for more than the third preset time, the bottom balancing is determined as the target balancing mode; the third preset time is greater than the first preset time; and the second preset open-circuit voltage is less than the first preset open-circuit voltage.

[0060] Optionally, if cloud-calibrated balancing is also present in the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes also includes:

[0061] If none of the top static balancing, top dynamic balancing, middle balancing and bottom balancing is turned on for more than a fourth preset time, cloud-calibrated balancing is determined as the target balancing mode; the fourth preset time is longer than the third preset time;

[0062] Accordingly, balancing the battery based on the target balancing mode includes:

[0063] Send a prompt message; the prompt message is used to remind the user to perform AC charging and fully charge to achieve the execution conditions of top static balance, top dynamic balance or mid-section balance.

[0064] Optionally, if cloud-calibrated balancing is present but bottom balancing is not present among the currently used balancing modes, determining the target balancing mode according to battery status information and execution conditions of the currently used balancing modes also includes:

[0065] When the stored second balancing time is not greater than 0, if none of the top static balancing, top dynamic balancing, and mid-segment balancing is enabled for more than a fourth preset time, cloud-calibrated balancing is determined as the target balancing mode; the fourth preset time is greater than the second preset time;

[0066] Accordingly, balancing the battery based on the target balancing mode includes:

[0067] Send a prompt message; the prompt message is used to remind the user to perform AC charging and fully charge to achieve the execution conditions of top static balance, top dynamic balance or mid-section balance.

[0068] Optionally, the method further includes:

[0069] After the battery is charged, if the rest time of the battery is greater than the preset rest time, the open circuit voltage of each single cell is obtained.

[0070] Optionally, the priorities of the balancing modes from high to low are: top static balancing, top dynamic balancing, middle balancing, bottom balancing, and cloud-calibrated balancing. Then, based on the battery status information, determining a target balancing mode from the multiple balancing modes includes:

[0071] Based on the battery status information and the priorities of the currently used balancing modes, the battery status information and the satisfaction of the execution conditions of each balancing mode are judged in descending order of priority until a target balancing mode is determined. Different balancing modes correspond to different execution conditions. The target balancing mode is the balancing mode determined from the currently used balancing modes when the battery status information meets the corresponding execution conditions.

[0072] Optionally, the priorities of the balancing modes from high to low are: top static balancing, top dynamic balancing, middle balancing, bottom balancing, and cloud-calibrated balancing. Then, based on the battery status information, determining a target balancing mode from the multiple balancing modes includes:

[0073] According to the battery status information and the execution conditions of each balancing mode currently in use, the balancing mode that meets the corresponding execution conditions is selected;

[0074] The balancing mode with the highest priority among the filtered balancing modes is determined as the target balancing mode.

[0075] In a second aspect, the present invention further provides a battery balancing device, comprising:

[0076] a determination module, configured to determine a target balancing mode from a plurality of balancing modes based on battery status information; wherein the battery status information includes battery status information during charging and / or after charging;

[0077] A balancing module is configured to balance the battery based on the target balancing mode.

[0078] In a third aspect, the present invention provides a controller comprising: at least one processor and a memory;

[0079] The memory stores computer-executable instructions;

[0080] The at least one processor executes the computer-executable instructions stored in the memory, so that the at least one processor performs the method as described in any one of the first aspects.

[0081] In a fourth aspect, the present invention provides an electrical device comprising: a battery and a controller, wherein the battery comprises a plurality of single cells; and the controller is configured to execute any one of the methods described in the first aspect.

[0082] In a fifth aspect, the present invention provides a computer-readable storage medium, in which computer-executable instructions are stored. When a processor executes the computer-executable instructions, the method described in any one of the first aspects is implemented.

[0083] In a sixth aspect, the present invention provides a computer program product, comprising a computer program, which, when executed by a processor, implements the method as described in any one of the first aspects.

[0084] The present invention provides a battery balancing method, device, controller, and electrical equipment. The method includes: determining a target balancing mode from multiple balancing modes based on battery status information, wherein the battery status information includes battery status information during and / or after charging. The target balancing mode is used to balance the battery based on the target balancing mode. This allows the target balancing mode to be selected from multiple balancing modes without being limited to a single balancing mode, thereby improving the flexibility and accuracy of battery balancing. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0086] Figure 1 An application scenario diagram provided by an embodiment of the present invention;

[0087] Figure 2 A flowchart of a battery balancing method provided by an embodiment of the present invention;

[0088] Figure 3 A graph showing the relationship between the remaining capacity and the open circuit voltage of a lithium iron phosphate battery provided in an embodiment of the present invention;

[0089] Figure 4 A schematic diagram of a battery charging voltage curve and a voltage difference curve provided by an embodiment of the present invention;

[0090] Figure 5 A schematic flow chart of another battery balancing method provided by an embodiment of the present invention;

[0091] Figure 6 A schematic structural diagram of a battery balancing device provided by an embodiment of the present invention;

[0092] Figure 7 A schematic diagram of the hardware structure of a controller provided in an embodiment of the present invention.

[0093] The above drawings illustrate specific embodiments of the present invention, which will be described in more detail below. These drawings and the accompanying description are not intended to limit the scope of the present invention in any way, but rather to illustrate the concept of the present invention to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0094] Exemplary embodiments are described in detail herein, with examples illustrated in the accompanying drawings. When the following description refers to the drawings, identical numerals in different figures represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present invention.

[0095] In this document, it should be understood that the terms involved are only used to facilitate understanding and do not represent any limitation on the meaning. In addition, the number of any element in the drawings is for illustration and not limitation, and any naming is only for distinction and does not have any limiting meaning.

[0096] The data involved in the present invention may be data authorized by the user or fully authorized by all parties, and the collection, dissemination, and use of the data shall comply with the requirements of relevant national laws and regulations.

[0097] The voltage of a single cell in a power battery (such as a lithium-ion battery) is only a few volts, resulting in low energy consumption. To increase the energy and voltage of a power battery, several cells can be connected in series. Currently, series battery packs are widely used in battery vehicles and backup power supplies.

[0098] With the use of series battery packs, the capacity of the series battery pack that can be charged and discharged is less than the capacity of the smallest capacity single cell, which affects the capacity of the entire battery pack. Therefore, balancing technology is needed to adjust the capacity of the single cell.

[0099] Some technologies can perform balancing based on the voltage difference between individual cells. For example, top-level dynamic balancing involves determining the difference between the voltage of each cell and the minimum voltage when the series battery pack is fully charged. When the difference exceeds a threshold, the corresponding cell undergoes balancing for a specified duration. This approach can provide limited flexibility, for example requiring the battery to be fully charged before balancing can be performed.

[0100] Therefore, a new battery balancing method is needed to solve the problem of poor flexibility when performing battery balancing operations. Based on the above problem, this application considers integrating multiple balancing methods, and can select a target balancing mode from multiple balancing modes. Different balancing modes have different execution conditions. When one balancing mode is not satisfied, another balancing mode may be satisfied to achieve battery balancing, thereby improving the flexibility of balancing operations. Figure 1 This is an application scenario diagram provided by an embodiment of the present invention. Figure 1 As shown, a target balancing mode can be selected from multiple balancing modes and the battery can be balanced. The remaining capacity of each single cell is quite different before balancing. After multiple balancing steps, the remaining capacity of each single cell is similar or the same.

[0101] Figure 2 A flowchart of a battery balancing method provided in an embodiment of the present invention includes:

[0102] Step S201: Determine a target balancing mode from a plurality of balancing modes based on battery status information; wherein the battery status information includes battery status information during charging and / or after charging.

[0103] Typically, when balancing batteries, a balancing mode is used. For example, one of the top dynamic balancing mode, mid-range balancing mode, or bottom balancing mode is used. When using the top dynamic balancing mode, the battery must be fully charged before balancing can be triggered. When using the mid-range balancing mode, the inflection point capacity of each cell must be detected before balancing can be performed. When using the bottom balancing mode, the voltage of each cell must be within the voltage range below the low voltage platform.

[0104] When only one of the above balancing modes is used for battery balancing, specific conditions must be met before the balancing operation can be performed, resulting in poor flexibility. For example, when battery balancing is performed based only on top dynamic balancing, the battery must be fully charged. If the user does not fully charge the battery for a long time, battery balancing cannot be triggered, resulting in the need for frequent full charging of the battery. When battery balancing is performed based only on mid-range balancing, it is necessary to detect the inflection point and determine the corresponding inflection point capacity. Detecting the inflection point requires low-current charging, which takes a long time.

[0105] Therefore, multiple balancing methods are integrated, and a target balancing mode is selected from multiple balancing modes based on the battery status information during and / or after charging. For example, when battery balancing is required for the first time and the battery has reached full charge, top dynamic balancing can be used as the target balancing mode. When battery balancing is required for the next time and the battery has not reached full charge, but the inflection points of each single cell have been detected during the battery charging process and the corresponding inflection point capacities have been determined, mid-range balancing can be used as the target balancing mode.

[0106] The battery status information may be one or more of the voltage of each single cell during charging, the voltage of each single cell after charging is completed, and whether an inflection point is detected.

[0107] Step S202: Balancing the battery based on the target balancing mode.

[0108] After determining the target balancing mode, the battery can be balanced based on the target balancing mode. Different balancing modes have different balancing methods. For example, when using top dynamic balancing, since the average balancing current is fixed, the balancing operation can be started for a certain length of time on the single cells that need to be balanced, thereby achieving battery balancing. When using mid-range balancing, the required balancing amount of single cells can be determined based on the inflection point capacity of each single cell to determine the balancing duration, thereby achieving battery balancing.

[0109] The present invention provides a battery balancing method, which includes: determining a target balancing mode from multiple balancing modes based on battery status information, wherein the battery status information includes battery status information during and / or after charging. The method is used to balance the battery based on the target balancing mode. This method can achieve the target balancing mode selection from multiple balancing modes without being limited to a single balancing mode, thereby improving the flexibility and accuracy of battery balancing.

[0110] Optionally, the multiple balancing modes include two or more of the following combinations: top static balancing, top dynamic balancing, middle balancing, bottom balancing and cloud-calibrated balancing.

[0111] Top static balancing is a new balancing mode proposed. This balancing mode is based on the characteristic that the open circuit voltage of lithium iron phosphate batteries rises rapidly at the top stage of the remaining capacity. The remaining capacity is determined according to the open circuit voltage, thereby obtaining a balancing solution for the target balancing amount of the single cell.

[0112] Optionally, the battery status information includes: the charging voltage of each single cell in the battery and the open circuit voltage of each single cell in the battery; the battery status information satisfies the execution condition of top static balancing if:

[0113] The charging voltage of the target single cell in the battery status information reaches the full charge condition, and the maximum open circuit voltage among the open circuit voltages of the single cells in the battery status information is greater than the first preset open circuit voltage; the target single cell is the single cell with the highest charging voltage.

[0114] Top static balancing also requires the battery to reach full charge conditions. Specifically, the charging voltage of each single cell of the battery during the charging process can be obtained. When the charging voltage of the target single cell is greater than the full charge voltage threshold under AC charging, it can be determined that the battery meets the full charge condition. The charge and discharge strategy is to stop charging when a single cell is fully charged. Therefore, when the single cell with the highest charging voltage reaches the full charge voltage threshold, it is determined that the full charge condition is met. Optionally, the full charge voltage threshold of the lithium iron phosphate battery is 3.65V.

[0115] Another condition for performing top static balancing is that the maximum open-circuit voltage among the open-circuit voltages of the single cells is greater than a first predetermined open-circuit voltage. Figure 3 A diagram showing the relationship between the remaining capacity and the open circuit voltage of a lithium iron phosphate battery provided in an embodiment of the present invention is shown in FIG. Figure 3 As shown, when the remaining capacity (SOC, State Of Charge, or state of charge) is greater than 97%, the open circuit voltage rises rapidly, so that the remaining capacity corresponding to the open circuit voltage can be accurately obtained, and battery balancing can be performed based on the determined remaining capacity. Therefore, the above-mentioned first preset open circuit voltage is the open circuit voltage corresponding to the remaining capacity equal to 97%. Only when this condition is met can the remaining capacity of each single cell be accurately obtained. Optionally, the maximum open circuit voltage here is greater than the first preset open circuit voltage. When the open circuit voltage of other single cells is less than the first preset open circuit voltage, the remaining capacity of other single cells can be calculated according to 97%.

[0116] Top dynamic balancing refers to the process of determining during battery charging that the voltage of each cell is the charging voltage. When the highest charging voltage reaches the full charge voltage threshold, the voltage difference between each cell and the cell with the lowest charging voltage is determined. For cells with a voltage difference exceeding the set value, balancing is initiated for a certain period of time. Because the remaining capacity of each cell cannot be accurately calculated based on the charging voltage of each cell, and therefore the capacity difference between each cell cannot be calculated, to reduce the risk of over-balancing, top dynamic balancing typically only discharges a small amount of capacity. Therefore, it is impossible to align the capacity of each cell in a single top dynamic balancing operation. Multiple full charges are required to achieve the desired capacity alignment.

[0117] Compared with top dynamic balancing, the top static balancing method can more clearly know the capacity difference of each single cell at the top, thereby improving the accuracy of the balancing calculation, achieving better balancing effect, and eliminating the need for multiple full charges, which can reduce the requirement for the number of full charges of the battery.

[0118] Mid-segment balancing is a method that detects the inflection point of each single cell to determine the inflection point capacity, and then performs balancing based on the inflection point capacity. Balancing based on the inflection point capacity is because: when each single cell starts charging from a capacity of 0, the curves before the inflection point are the same, that is, the inflection points of each single cell are the same, but the actual characteristic inflection points of each single cell may be different because the remaining capacity of each single cell is different when charging starts. Therefore, based on the inflection point capacity of each single cell, the difference in the starting remaining capacity of each single cell when charging can be determined, so that balancing can be performed.

[0119] Optionally, during the charging process, the inflection point of the charging voltage curve of each single cell can be found, also known as a characteristic point. There are two inflection points during the charging process, one is the high voltage platform inflection point, and the other is the low voltage platform inflection point. Figure 4 A schematic diagram of a battery charging voltage curve and a voltage difference curve provided by an embodiment of the present invention, such as Figure 4 As shown, the vertical axis of the battery charging voltage curve is voltage, and the horizontal axis is the remaining capacity (or charged capacity); the vertical axis of the voltage difference curve is voltage difference, and the horizontal axis is the remaining capacity. The battery voltage-capacity characteristic curve has three intervals where the voltage changes slowly, called voltage platform areas. There is an area between two voltage platform areas where the voltage changes rapidly. The point where the voltage changes fastest in this area is called the voltage platform inflection point. The higher voltage is called the high voltage platform inflection point (denoted as HVTP, High Voltage of Platform Point), and the lower voltage is called the low voltage platform inflection point (denoted as LVTP, Low Voltage of Platform Point). Figure 4 The voltage platform inflection point is represented by the maximum value point on the voltage differential curve. During the charging process, a battery charging voltage curve as described above can be obtained for each single cell. By processing this curve to obtain the voltage differential curve, the inflection point is obtained.

[0120] Optionally, battery balancing can be performed here by detecting the inflection point of the high voltage platform, and the balancing time of each single cell can be determined according to the capacity corresponding to the inflection point of each single cell. In addition, for a single cell that has not detected the inflection point of the high voltage platform, if a low voltage platform inflection point is detected, a certain bias is superimposed on the low voltage platform inflection point as the high voltage platform inflection point of the single cell, and the corresponding capacity is determined based on the high voltage platform inflection point, and then the balancing operation is performed in combination with the capacity corresponding to the high voltage platform inflection point of other single cells.

[0121] Bottom balancing requires that the open-circuit voltage of at least one cell be in a relatively low remaining capacity range (below the battery's low-voltage platform). Because the voltage increases more rapidly in this range, the remaining capacity can be accurately calculated based on the cell's open-circuit voltage. After the battery has been idle for an extended period, balancing is initiated when the voltage difference between each cell's open-circuit voltage and the lowest open-circuit voltage exceeds a preset threshold. The balancing amount is calculated similarly to top static balancing.

[0122] Cloud-based calibration balancing is a backup balancing method that can be performed when other balancing modes have not been used for a long time. Specifically, it reminds the user to fully charge the battery to meet the execution conditions of other balancing modes (top static balancing, top dynamic balancing, or mid-range balancing), so that other balancing modes can be used for battery balancing.

[0123] The above-mentioned top static balance and top dynamic balance correspond to the interval segment with higher SOC, the middle balance corresponds to the interval segment where the SOC is in the voltage plateau period, and the bottom balance corresponds to the interval segment with lower SOC, so that balancing can be achieved when the battery is in different SOC ranges.

[0124] By setting two or more of the above-mentioned balancing modes, it is possible to select a suitable balancing mode to perform balancing when the batteries are in different remaining capacity ranges (SOC ranges), thereby increasing the possibility of triggering battery balancing.

[0125] Optionally, determining a target balancing mode from a plurality of balancing modes based on battery status information includes:

[0126] The target balancing mode is determined based on the battery status information and the execution conditions of each balancing mode currently in use; different balancing modes correspond to different execution conditions; the target balancing mode is the balancing mode determined from each balancing mode currently in use when the battery status information meets the corresponding execution conditions.

[0127] When determining a target balancing mode from multiple balancing modes, the target balancing mode may be determined based on battery status information. Each balancing mode has different execution conditions. When the battery status information satisfies the execution conditions of the balancing mode, the balancing mode may be used for battery balancing.

[0128] Optionally, the priorities of the currently used balancing modes can be set, and the balancing modes can be judged in descending order of priority until a balancing mode whose battery status information meets the corresponding execution conditions is determined, and the balancing mode is determined as the target balancing mode.

[0129] Optionally, the currently used balancing modes may be judged separately to select the balancing modes whose battery status information meets the corresponding execution conditions, and then the balancing mode with the highest priority among the selected balancing modes may be determined as the target balancing mode.

[0130] By setting different execution conditions for each balancing mode, it is determined whether the battery status information meets the corresponding execution conditions, so as to accurately select the target balancing mode.

[0131] Optionally, if top static balancing exists among the balancing modes currently in use, determining the target balancing mode according to the battery status information and the execution conditions of the balancing modes currently in use includes:

[0132] After battery charging is completed, if it is determined that the battery has a balancing requirement, and the charging voltage of the target single cell in the battery status information reaches the full charging condition, and the maximum open-circuit voltage among the open-circuit voltages of the individual single cells in the battery status information is greater than a first preset open-circuit voltage, then top static balancing is determined as the target balancing mode; the target single cell is the single cell with the highest charging voltage.

[0133] When determining the target balancing mode, the target balancing mode can be judged and selected after battery charging is completed.

[0134] When the battery is fully charged, it can be determined whether the battery needs balancing. If the battery needs balancing, it is necessary to continue to determine the target balancing mode and perform balancing operations. If the battery does not need balancing, it is not necessary to continue to determine the target balancing mode and perform balancing operations.

[0135] Optionally, the method further includes:

[0136] After the battery is charged, if the rest time of the battery is greater than the preset rest time, the open circuit voltage of each single cell is obtained.

[0137] After charging is complete, the battery can be left to rest. If the rest time exceeds a preset rest period, such as two hours, the voltage of each cell is obtained as the open-circuit voltage. Specifically, the time the relay is disconnected can be recorded. If the relay is disconnected for longer than the preset rest period, the subsequent voltage obtained is the open-circuit voltage. Based on the obtained open-circuit voltage of each cell, it can be determined whether the battery needs balancing.

[0138] After charging, the battery is left to rest for a certain period of time to accurately obtain the charging voltage of each single cell.

[0139] When it is necessary to determine the target balancing mode, since the top static balancing has the highest priority, it may be determined first whether the execution conditions of the top static balancing are met.

[0140] Specifically, we can first determine whether the charging voltage of the target single cell in the battery status information reaches the full charge condition. The charging voltage refers to the charging voltage of each single cell during the charging process of the battery. The single cell with the highest charging voltage is the target single cell. When the target single cell reaches the full charge voltage threshold, it means that the full charge condition is met.

[0141] Furthermore, after obtaining the open-circuit voltage of each battery cell, it is also possible to determine whether the maximum open-circuit voltage is greater than a first preset open-circuit voltage. If it is, this indicates that the open-circuit voltage is rapidly increasing at the top end, and top static balancing mode can be used for battery balancing. For example, the first preset open-circuit voltage can be the open-circuit voltage corresponding to a remaining capacity (SOC) of 97%.

[0142] After fully charging the battery, it is determined whether the battery needs balancing. When balancing is required, the top static balancing mode can be selected first to improve the balancing effect.

[0143] Optionally, determining whether the battery needs to be balanced includes:

[0144] When it is determined that the difference between the maximum open circuit voltage and the minimum open circuit voltage among the open circuit voltages corresponding to the individual battery cells is greater than a first preset difference, it is determined that the battery has a balancing requirement.

[0145] When determining whether battery balancing is required, the difference between the maximum open circuit voltage and the minimum open circuit voltage can be determined to be greater than a first preset difference. If so, it indicates that there is a large difference in the open circuit voltages of the two cells, and further battery balancing is required. For example, the first preset difference can be 10mV.

[0146] Optionally, balancing the battery based on the target balancing mode includes:

[0147] For each single cell, determining the corresponding remaining capacity according to the open circuit voltage of the single cell;

[0148] For each single cell in the battery except a first reference single cell, determining an equalization value for each single cell according to the remaining capacity of the single cell and the remaining capacity of the first reference single cell; wherein the first reference single cell is the single cell with the smallest open circuit voltage among all the single cells when fully charged;

[0149] The single battery cells are balanced according to the balance values of the single battery cells.

[0150] When it is determined that the target balancing mode is top static balancing, the battery can be balanced based on this balancing mode. Specifically, for each single cell, the corresponding remaining capacity can be determined based on the open circuit voltage of the single cell. After obtaining the remaining capacity of each single cell, the first reference single cell can be determined. The first reference single cell is the single cell with the smallest open circuit voltage when fully charged. For any single cell other than the first reference single cell, the difference between the remaining capacity of the single cell and the remaining capacity of the first reference single cell can be calculated, and the product of the difference and the capacity of the single cell can be determined as the balancing value of the single cell. After obtaining the balancing value, the balancing time can be determined based on the balancing value, and then the balancing can be started based on the balancing time.

[0151] Exemplarily, the balancing value of the i-th single cell is ΔQ[i]=(SOC[i]-SOC[Vmin])*Cap[i], and the balancing time is ΔQ[i] / Imean, where Imean is the average balancing current.

[0152] When determining the remaining capacity corresponding to each single cell, for a single cell whose open-circuit voltage is lower than the first preset open-circuit voltage, the remaining capacity of the single cell is set to the remaining capacity corresponding to the first preset open-circuit voltage (the minimum SOC is 97%) to avoid inaccurate remaining capacity due to the open-circuit voltage not being in the stage of rapid upward movement at the top.

[0153] By determining the remaining capacity of each single battery cell, the balancing amount of each single battery cell is determined based on the remaining capacity of each single battery cell, thereby achieving accurate balancing of each single battery cell.

[0154] Optionally, determining the corresponding remaining capacity according to the open circuit voltage of the single battery cell includes:

[0155] The remaining capacity corresponding to the open circuit voltage of the single cell is determined according to a preset corresponding relationship; the preset corresponding relationship represents the relationship between the remaining capacity and the open circuit voltage.

[0156] When determining the remaining capacity of each battery cell, the determination can be based on a preset correspondence relationship. The preset correspondence relationship represents the relationship between the remaining capacity and the open circuit voltage. Based on this preset relationship, after determining the open circuit voltage of each battery cell, the remaining capacity corresponding to the open circuit voltage can be determined. Optionally, the preset correspondence relationship can be in the form of a data table, which is a pre-embedded SOC-OCV table, where OCV (Open Circuit Voltage) represents the open circuit voltage.

[0157] Based on the preset correspondence, the remaining capacity of each single battery cell can be determined simply, conveniently and accurately.

[0158] Optionally, if top dynamic balancing is present in each of the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of each of the currently used balancing modes further includes:

[0159] If the maximum open-circuit voltage among the open-circuit voltages of the individual battery cells in the battery status information is less than or equal to the first preset open-circuit voltage, and it is determined that the stored first balancing time is greater than 0, top dynamic balancing is determined as the target balancing mode;

[0160] The first balancing time is calculated and stored after the battery is fully charged and the battery status information satisfies the execution condition of the top dynamic balancing.

[0161] If the maximum open-circuit voltage is determined to be less than or equal to the first predetermined open-circuit voltage, indicating that the open-circuit voltages of the individual cells are not in the top-end rapid rise phase, top-end static balancing cannot be used for battery balancing. For example, the open-circuit voltage corresponding to SOC = 97% is not satisfied.

[0162] When top static balancing cannot be used for cell balancing, it can be determined whether top dynamic balancing can be used for cell balancing. Specifically, it can be determined whether the first balancing duration is greater than 0. If it is greater than 0, it means that the execution conditions of top dynamic balancing are met, and top dynamic balancing can be determined as the target balancing mode.

[0163] Optionally, the first balancing time may be calculated and stored after the battery is fully charged and when it is determined that the battery status information meets the execution condition of the top dynamic balancing.

[0164] Optionally, the first balancing duration may be stored in NVM (non-volatile memory).

[0165] The above method can be used to preferentially select the top dynamic balancing mode for battery balancing when the top static balancing mode is not satisfied.

[0166] Optionally, the battery status information satisfies the execution conditions of top dynamic balancing:

[0167] The charging voltage of the target single cell in the battery status information reaches the full charging condition and the top static balancing is not started for more than a first preset time.

[0168] When determining whether the battery status information meets the conditions for top-end dynamic balancing, in addition to determining whether the charging voltage of the target single cell has reached the full charge condition, it is also necessary to determine whether top-end static balancing has not been initiated for more than a first preset time period. For example, the first preset time period may be one month. If the time difference between the current time and the last time top-end static balancing was initiated is greater than one month, the conditions for top-end dynamic balancing are met.

[0169] By determining whether the top static balancing is not enabled for more than a first preset time, the top static balancing can be preferentially used again to perform battery balancing within the first preset time since the last enabling of the top static balancing.

[0170] Optionally, the method further includes:

[0171] Obtaining the charging voltage of each single cell when the battery reaches a full charge condition during the charging process, and for any single cell in the battery except the second reference single cell, when the difference between the charging voltage corresponding to the single cell and the charging voltage of the second reference single cell is greater than a second preset difference, storing the identifier of the single cell and the corresponding first balancing time;

[0172] The second reference single cell is a cell with the smallest charging voltage among all the single cells.

[0173] When determining the first balancing duration, it's actually necessary to determine which cells to balance. Specifically, this can be determined based on the charging voltage of each cell. First, a second reference cell can be determined, which is the cell with the smallest charging voltage. For other cells, when the difference between the charging voltage and the charging voltage of the second reference cell is greater than a second preset difference, it indicates that the cell needs to be balanced. For the i-th cell, this means determining whether ΔV[i] = V[i] - Vmin exceeds the second preset difference.

[0174] When it is determined that a single cell needs to be balanced, the cell identifier and first balancing duration are stored. For example, the first balancing duration can be a fixed value for different cells; alternatively, the first balancing duration can vary slightly for different cells. For example, when the difference between the charging voltage and the charging voltage of the second reference cell is large, the first balancing duration is long; when the difference between the charging voltage and the charging voltage of the second reference cell is small, the first balancing duration is short.

[0175] By determining and storing the identifiers of the single cells that need to be balanced in advance, when it is determined that the top dynamic balancing method can be used for battery balancing, the balancing operation can be performed quickly without having to determine which single cells need to be balanced, which can improve processing efficiency.

[0176] Optionally, the method further includes:

[0177] After the top dynamic balancing is determined as the target balancing mode and the battery is balanced, the stored first balancing duration is reset to 0.

[0178] After the top dynamic balancing is determined as the target balancing mode and the batteries are balanced, in order to avoid misjudgment next time, the stored first balancing duration may be reset to 0.

[0179] After balancing the batteries based on top dynamic balancing, the first balancing duration is reset to 0, thereby avoiding a misjudgment of whether top dynamic balancing can be used for battery balancing next time.

[0180] Optionally, if mid-segment balancing still exists in the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes further includes:

[0181] When the stored first balancing time length is not greater than 0 and the stored second balancing time length is greater than 0, determining the mid-segment balancing as the target balancing mode;

[0182] The second balancing time is calculated and stored when the battery status information meets the execution condition of mid-segment balancing.

[0183] When it is determined that the first balancing time is not greater than 0, it indicates that the execution condition of the top dynamic balancing is not met, and it can be determined whether the stored second balancing time is greater than 0. When the stored second balancing time is greater than 0, it indicates that the battery balancing can be performed using the mid-segment balancing method.

[0184] The second balancing duration is a duration for balancing each battery cell using mid-segment balancing, which is calculated based on the battery status information during the charging process when the mid-segment balancing execution condition is met.

[0185] The second balancing duration may be calculated when it is determined that the battery status information meets the execution condition of mid-segment balancing, and stored in the NVM.

[0186] The above method can be used to preferentially select the middle section balancing method for battery balancing when the top section dynamic balancing is not satisfied.

[0187] Optionally, the battery status information satisfies the execution conditions of mid-segment balancing:

[0188] During the charging process, the inflection point capacities of at least two single cells detected are valid, and top static balancing or top dynamic balancing is not started for more than a second preset time period;

[0189] The second preset duration is greater than the first preset duration.

[0190] Specifically, it can be determined whether the inflection point capacity is detected during the charging process. If the inflection point capacity of at least two single cells is detected to be valid, the time for which the top static balancing or the top dynamic balancing is not turned on can be determined. If the top static balancing or the top dynamic balancing is not turned on for more than a second preset time, it means that the battery balancing can be performed using the mid-segment balancing method.

[0191] The second preset time period may be longer than the first preset time period, so that when the top static equalization and the top dynamic equalization have not been performed for a long time, the middle equalization may be performed. For example, the first preset time period is one month and the second preset time period is two months.

[0192] Optionally, in addition to determining that top static balancing or top dynamic balancing is not enabled during the second preset time period, it may also be determined that full charging is not performed during the second preset time period.

[0193] Furthermore, the battery can also use mid-segment balancing to perform battery balancing when the charging voltage of the target single cell described in the battery status information does not reach the full charge condition, that is, when the maximum charging voltage is less than the full charge voltage threshold (such as 3.65V), and the battery status information meets the execution conditions of mid-segment balancing. Balancing the battery using mid-segment balancing does not require ensuring that the charging voltage of the target single cell reaches the full charge condition. It only needs to consider whether the battery status information meets the execution conditions of mid-segment balancing.

[0194] Optionally, the method further includes:

[0195] Obtaining the inflection point capacity and inflection point capacity confidence corresponding to at least two single battery cells detected during the charging process;

[0196] When the inflection point capacity confidence level is greater than a preset confidence level, it is determined that the inflection point capacity corresponding to the inflection point capacity confidence level is valid.

[0197] During the charging process, when charging at a low current, the inflection points of some or all of the battery cells may be detected. Specifically, during the charging process, the voltage and charge capacity of each battery cell are obtained in real time, and the inflection point capacity and inflection point capacity confidence level of each battery cell are calculated.

[0198] When the detected inflection point is a high voltage platform inflection point, the inflection point capacity is expressed as Q_HVTP and the inflection point capacity confidence is expressed as HVTP_Valid. When the inflection point capacity confidence is greater than the preset confidence, it can be determined that the corresponding inflection point capacity is valid.

[0199] By determining whether the top static balancing or the top dynamic balancing is not started for more than the second preset time period, the top static balancing or the top dynamic balancing can be preferentially used for battery balancing.

[0200] Optionally, the method further includes:

[0201] For any single cell in the battery except a third reference single cell, determining a relative capacity difference of the single cell based on the inflection point capacity of the single cell detected during charging and the inflection point capacity of the third reference single cell; the third reference single cell is the single cell corresponding to the maximum inflection point capacity among all inflection point capacities;

[0202] A second balancing time duration corresponding to the single battery cell is determined according to the relative capacity difference, and the identifier of the single battery cell and the corresponding second balancing time duration are stored.

[0203] When determining the second balancing time of each single cell, the third reference single cell can be determined first. The third reference single cell is the single cell corresponding to the maximum value of the inflection point capacity, that is, the single cell with the lowest voltage. For any single cell other than the third reference single cell, the relative capacity difference of the single cell can be determined based on the inflection point capacity of the single cell and the inflection point capacity of the third reference single cell. Specifically, the inflection point capacity is Q_HVTP. For the i-th single cell, the relative capacity difference of the single cell is: ΔQ_HVTP[i]=max(Q_HVTP)-Q_HVTP[i]. That is, the single cells other than the single cell with the lowest voltage are discharged so that the inflection point capacity of each single cell approaches the inflection point capacity of the single cell with the lowest voltage.

[0204] After determining the relative capacity difference, a second balancing time can be determined based on the relative capacity difference and the average balancing current. Specifically, when the relative capacity difference is greater than a preset value, the cell can be balanced and the second balancing time calculated. When the relative capacity difference is less than the preset value, the cell can be unbalanced and the second balancing time does not need to be calculated. When a cell requires balancing, the second balancing time is the ratio of the relative capacity difference to the average balancing current. The second balancing time for the i-th cell is expressed as ΔQ_HVTP[i] / Imean.

[0205] By determining and storing the second balancing time of each single cell in advance, when it is determined that the mid-segment balancing method can be used for battery balancing, the balancing operation can be performed quickly without having to determine which single cells need to be balanced or calculate the balancing time, thereby improving processing efficiency.

[0206] During the charging process, the battery status information is obtained and a determination is made as to whether the conditions for top-end dynamic balancing are met. If so, the first balancing duration is calculated and stored. If the conditions for top-end dynamic balancing are not met, a determination is made as to whether the conditions for mid-range balancing are met. If so, the second balancing duration is calculated and stored. After executing the above steps, the balancing operation is not started until the preconditions for top-end static balancing (the battery has been stationary for a certain period of time) are met. A unified determination is then made and balancing is started.

[0207] Optionally, the method further includes:

[0208] The mid-segment balancing is determined as the target balancing mode, and after the battery is balanced, the stored second balancing duration is reset to 0.

[0209] When the mid-segment equalization is determined as the target equalization mode and equalization is performed, similarly, the stored second equalization duration can be reset to 0 to avoid subsequent misjudgment.

[0210] After balancing the batteries based on mid-segment balancing, resetting the second balancing time to 0 can avoid misjudging whether mid-segment balancing can be used for battery balancing next time.

[0211] Optionally, if mid-segment balancing exists but top dynamic balancing does not exist among the currently used balancing modes, determining the target balancing mode according to battery status information and execution conditions of the currently used balancing modes further includes:

[0212] When the maximum open-circuit voltage among the open-circuit voltages of the individual battery cells in the battery status information is less than or equal to the first preset open-circuit voltage, and it is determined that the stored second balancing time is greater than 0, mid-segment balancing is determined as the target balancing mode;

[0213] The second balancing time is calculated and stored when the battery status information meets the execution condition of mid-segment balancing.

[0214] Optionally, the battery status information satisfies the execution conditions of mid-segment balancing:

[0215] During the charging process, the inflection point capacities of at least two single battery cells detected are valid, and top static balancing is not enabled for more than a second preset time period.

[0216] If the currently used balancing modes include top static balancing and mid-range balancing, but do not include top dynamic balancing, then when determining the target balancing mode, if the execution conditions for top static balancing are not met, that is, if the maximum open-circuit voltage among the open-circuit voltages of the individual cells in the battery status information is less than or equal to the first preset open-circuit voltage, then it can be determined whether the execution conditions for mid-range balancing are met. Specifically, it can be determined whether the second balancing time is greater than 0. If the second balancing time is greater than 0, it can be indicated that the battery status information meets the execution conditions for mid-range balancing, and the second balancing time is thus calculated and stored.

[0217] Optionally, if top dynamic balancing does not exist in any of the currently used balancing modes, the execution conditions for mid-range balancing are: valid inflection point capacities of at least two battery cells are detected, and top static balancing has not been activated for more than a second preset time. In this case, the execution conditions for mid-range balancing can be determined to be met. It is not necessary to determine whether top dynamic balancing has not been activated for more than the second preset time.

[0218] Through the above method, it is realized whether the middle section balance can be determined as the target balance mode when there is no top dynamic balance mode and the top static balance mode is not satisfied.

[0219] Furthermore, the battery can also use mid-segment balancing to perform battery balancing when the charging voltage of the target single cell described in the battery status information does not reach the full charge condition, that is, when the maximum charging voltage is less than the full charge voltage threshold (such as 3.65V), and the battery status information meets the execution conditions of mid-segment balancing. Balancing the battery using mid-segment balancing does not require ensuring that the charging voltage of the target single cell reaches the full charge condition. It only needs to consider whether the battery status information meets the execution conditions of mid-segment balancing.

[0220] Optionally, if bottom balancing still exists in the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes further includes:

[0221] When the stored second equalization duration is not greater than 0, if the minimum open-circuit voltage among the open-circuit voltages of each single cell is less than the second preset open-circuit voltage and none of the top static equalization, top dynamic equalization, and middle-section equalization is started for more than a third preset duration, the bottom equalization is determined as the target equalization mode; the third preset duration is greater than the second preset duration; the second preset open-circuit voltage is less than the first preset open-circuit voltage.

[0222] When the second equalization duration is not greater than 0, it means that the middle-section equalization method cannot be used for battery equalization. At this time, it can be determined whether the bottom equalization method can be used for battery equalization. After the battery is charged, if the execution conditions of the above three equalization modes are not met, after using the battery for a period of time and then standing still, the execution conditions of the bottom equalization may be met.

[0223] Specifically, the open-circuit voltages of each single cell can be collected. When the minimum open-circuit voltage is less than the second preset open-circuit voltage and none of the top static equalization, top dynamic equalization, and middle-section equalization is started for more than a third preset duration, it means that the bottom equalization method can be used for battery equalization.

[0224] The minimum open-circuit voltage being less than the second preset open-circuit voltage means Vmin < Vth, where Vth is the lowest threshold of the low platform and is a preset value, such as Figure 3 , which is the open-circuit voltage when the SOC is about 18%.

[0225] When performing the bottom equalization judgment, it is also necessary to determine whether none of the top static equalization, top dynamic equalization, and middle-section equalization has been executed for a third preset duration. The third preset duration is greater than the second preset duration. Exemplarily, the third preset duration is 3 months and the second preset duration is 2 months.

[0226] Through the above judgment, when the open-circuit voltage of the single cell is low, the remaining capacity of each single cell can be accurately obtained to satisfy the characteristic that the open-circuit voltage of the bottom stage quickly turns up, so as to perform bottom equalization.

[0227] Optionally, based on the target equalization mode, equalizing the battery includes:

[0228] For any single cell in the battery except the fourth reference single cell, when the difference between the open-circuit voltage corresponding to the any single cell and the open-circuit voltage of the fourth reference single cell is greater than a third preset difference, the corresponding remaining capacity is determined according to the open-circuit voltage of the any single cell;

[0229] The equalization value of each single cell is determined according to the remaining capacity of each single cell and the remaining capacity of the fourth reference single cell; the fourth reference single cell is the single cell with the smallest open-circuit voltage among all single cells in the current state;

[0230] The single battery cells are balanced according to the balance values of the single battery cells.

[0231] When battery balancing is performed using bottom balancing, the single cell that needs to be balanced can be determined first. The difference between the open circuit voltage corresponding to each single cell and the minimum open circuit voltage can be calculated to determine whether the single cell is balanced. When the difference is greater than the third preset difference, it indicates that the single cell needs to be balanced, and the corresponding remaining capacity can be determined based on the open circuit voltage of the single cell.

[0232] After determining that the remaining capacity of the single cell needs to be balanced, the difference with the remaining capacity of the fourth reference single cell can be calculated, and the difference can be determined as the balancing value of the single cell. The ratio of the balancing value to the average balancing current can be determined as the balancing time of the single cell.

[0233] By judging whether the execution conditions of bottom balancing are met, bottom balancing can be performed when top balancing and middle balancing cannot be executed.

[0234] Optionally, if bottom balancing exists but mid-balancing does not exist among the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes further includes:

[0235] When the stored first balancing time is not greater than 0, if the minimum open-circuit voltage among the open-circuit voltages of each single cell is less than the second preset open-circuit voltage and the top static balancing or the top dynamic balancing is not turned on for more than the third preset time, the bottom balancing is determined as the target balancing mode; the third preset time is greater than the first preset time; and the second preset open-circuit voltage is less than the first preset open-circuit voltage.

[0236] If the currently used balancing modes include top static balancing, top dynamic balancing and bottom balancing, but do not include middle balancing, then when the execution conditions of top dynamic balancing are not met, that is, the stored first balancing time is not greater than 0, it can be determined whether the execution conditions of bottom balancing are met, that is, the minimum open-circuit voltage among the open-circuit voltages of each single cell is less than the second preset open-circuit voltage and the top static balancing or top dynamic balancing is not turned on for more than the third preset time, without the need to determine whether the middle balancing is not turned on for more than the third preset time.

[0237] Since there is no mid-segment balance, the third preset time length only needs to be greater than the first preset time length, and there is no need to determine whether the third preset time length is greater than the second preset time length.

[0238] The above method can realize whether to determine bottom balancing as the target balancing mode when the execution conditions of top static balancing and top dynamic balancing are not met when top static balancing, top dynamic balancing and bottom balancing exist.

[0239] Optionally, if cloud-calibrated balancing is also present in the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes also includes:

[0240] If none of the top static balancing, top dynamic balancing, middle balancing and bottom balancing is turned on for more than a fourth preset time, cloud-calibrated balancing is determined as the target balancing mode; the fourth preset time is longer than the third preset time;

[0241] Accordingly, balancing the battery based on the target balancing mode includes:

[0242] Send a prompt message; the prompt message is used to remind the user to perform AC charging and fully charge to achieve the execution conditions of top static balance, top dynamic balance or mid-section balance.

[0243] If any of the top static balancing, top dynamic balancing, middle balancing, and bottom balancing is not performed for a fourth preset time period, cloud calibration balancing can be performed. The fourth preset time period can be longer than the third preset time period, for example, the fourth preset time period is 6 months and the third preset time period is 3 months.

[0244] Optionally, the time of each battery balancing and the target balancing mode may be recorded for subsequent determination of the target balancing mode.

[0245] When performing cloud-based calibration and balancing, a prompt message can be sent to the power-consuming device or user to remind the user to perform AC charging and fully charge the battery, so as to achieve the execution conditions of top static balancing, top dynamic balancing and mid-range balancing.

[0246] Cloud-calibrated balancing can ensure that top static balancing, top dynamic balancing or mid-segment balancing is performed every fourth preset time to avoid the battery failing to meet the execution conditions of each balancing mode for a long time and failing to balance.

[0247] Optionally, if cloud-calibrated balancing is present but bottom balancing is not present among the currently used balancing modes, determining the target balancing mode according to battery status information and execution conditions of the currently used balancing modes also includes:

[0248] When the stored second balancing time is not greater than 0, if none of the top static balancing, top dynamic balancing, and mid-segment balancing is enabled for more than a fourth preset time, cloud-calibrated balancing is determined as the target balancing mode; the fourth preset time is greater than the second preset time;

[0249] Accordingly, balancing the battery based on the target balancing mode includes:

[0250] Send a prompt message; the prompt message is used to remind the user to perform AC charging and fully charge to achieve the execution conditions of top static balance, top dynamic balance or mid-section balance.

[0251] If the currently used balancing modes include top static balancing, top dynamic balancing, mid-range balancing, and cloud-calibrated balancing, and the execution conditions for top static balancing and top dynamic balancing are not met, the execution conditions for mid-range balancing will be determined. If the execution conditions for mid-range balancing are not met, that is, the second balancing duration is not greater than 0, then a determination is made as to whether any of top static balancing, top dynamic balancing, and mid-range balancing has not been activated for more than a fourth preset duration. If so, cloud-calibrated balancing can be determined as the target balancing mode. Since bottom balancing does not exist, there is no need to determine whether bottom balancing has not been activated for more than the fourth preset duration.

[0252] Through the above method, it can be realized whether cloud-based calibration balancing can be determined as the target balancing mode when the execution conditions of top static balancing, top dynamic balancing, mid-section balancing and cloud-based calibration balancing are not met.

[0253] Optionally, the priorities of the balancing modes from high to low are: top static balancing, top dynamic balancing, middle balancing, bottom balancing, and cloud-calibrated balancing. Then, based on the battery status information, determining a target balancing mode from the multiple balancing modes includes:

[0254] Based on the battery status information and the priorities of the currently used balancing modes, the battery status information and the satisfaction of the execution conditions of each balancing mode are judged in descending order of priority until a target balancing mode is determined. Different balancing modes correspond to different execution conditions. The target balancing mode is the balancing mode determined from the currently used balancing modes when the battery status information meets the corresponding execution conditions.

[0255] Optionally, each balancing mode corresponds to a priority. When selecting a target balancing mode from multiple balancing modes, the selection may be made according to the priority of each balancing mode.

[0256] According to the difference in balancing effects, the priority of each balancing mode can be set in order from high to low. The specific order is: top static balancing, top dynamic balancing, middle balancing, bottom balancing and cloud-calibrated balancing.

[0257] Based on the previous analysis, the balancing effect of the top static balancing is better than that of the top dynamic balancing. The problem with the mid-segment balancing is that it is necessary to detect the inflection point under low current charging, and it is possible that the inflection point of some single cells cannot be detected (because it is not fully charged or the remaining capacity at the beginning of charging has exceeded the capacity corresponding to the inflection point of some single cells). In addition, the inflection point capacity determined based on this method is not accurate enough, so it may be possible to only balance some single cells after one charge. When the bottom balancing is executed, the capacity of the battery is small, and if the balancing is continued, it is easier to trigger the protection mechanism. Cloud-calibrated balancing requires reminders to the user, and the user experience is not good. Therefore, the priority of each balancing mode can be set based on the above priority order.

[0258] When determining the target balancing mode, the battery status information can be compared with the execution conditions of the balancing mode in descending order of priority to determine whether the battery status information meets the execution conditions of the balancing mode, thereby selecting the target balancing mode. For example, the battery status information is first determined to determine whether it meets the execution conditions of top-end static balancing. If so, top-end static balancing is determined as the target balancing mode. If not, the battery status information is then determined to determine whether it meets the execution conditions of top-end dynamic balancing. If so, top-end dynamic balancing is determined as the target balancing mode.

[0259] By judging each balancing mode in turn according to the priority, the balancing mode with higher balancing accuracy can be preferentially selected, and balancing can be performed when the battery is in different SOC ranges.

[0260] Optionally, the priorities of the balancing modes from high to low are: top static balancing, top dynamic balancing, middle balancing, bottom balancing, and cloud-calibrated balancing. Then, based on the battery status information, determining a target balancing mode from the multiple balancing modes includes:

[0261] According to the battery status information and the execution conditions of each balancing mode currently in use, the balancing mode that meets the corresponding execution conditions is selected;

[0262] The balancing mode with the highest priority among the filtered balancing modes is determined as the target balancing mode.

[0263] When determining a target balancing mode, the battery status information can be used to determine whether the execution conditions of each currently used balancing mode are met. For example, if the currently used balancing modes include the five balancing modes mentioned above, the battery status information can be determined to determine whether the execution conditions of each balancing mode are met to determine the balancing mode that meets the execution conditions. For example, if the battery status information is determined to meet the execution conditions of top dynamic balancing and mid-range balancing, these two balancing modes can be selected.

[0264] After selecting the currently executable balancing modes, the target balancing mode can be determined from the selected balancing modes, that is, the balancing mode with the highest priority among the selected balancing modes. If the selected balancing modes are top dynamic balancing and mid-range balancing, and top dynamic balancing has a higher priority than mid-range balancing, then top dynamic balancing can be determined as the target balancing mode.

[0265] By first screening the balancing modes that meet the corresponding execution conditions and then determining the target balancing mode from the screened balancing modes based on the priority, the target balancing mode can also be determined simply and conveniently.

[0266] In summary, during battery use, trigger judgments are made according to different scenarios. If multiple modes are valid at the same time, such as when both top balancing and middle balancing are satisfied after charging is completed, or when top balancing or bottom balancing is satisfied before the middle balancing is triggered and completed, the subsequent target balancing mode can be selected according to the priority of each balancing mode.

[0267] Figure 5 A flow chart of another battery balancing method provided by an embodiment of the present invention is shown as follows: Figure 5As shown, after charging the battery, if the standing time meets the conditions, it is determined whether the maximum open circuit voltage is greater than the first preset open circuit voltage. If the maximum open circuit voltage is greater than the first preset open circuit voltage, it is determined whether the difference between the maximum open circuit voltage and the minimum open circuit voltage is greater than the first preset difference. If it is greater than the first preset difference, the top static balance is turned on and the start time is recorded; if it is not greater than the first preset difference, all balances are turned off; when the standing time does not meet the conditions, the first balance time and the second balance time are calculated and stored. When the maximum open-circuit voltage is not greater than the first preset open-circuit voltage, determine whether the first balancing time is greater than 0. If it is greater than 0, start the top dynamic balancing and record the start-up time. If the first balancing time is not greater than 0, determine whether the second balancing time is greater than 0. If the second balancing time is greater than 0, start the middle balancing and record the start-up time. If the second balancing time is not greater than 0, determine whether the minimum open-circuit voltage is less than the second preset open-circuit voltage. If so, determine whether the above three balancing methods have not been turned on for a period of time. If so, start the bottom balancing and record the start-up time. If not, do not perform any balancing operation. If the minimum open-circuit voltage is not less than the second preset open-circuit voltage, determine whether the above four balancing methods have not been turned on for a long time. If so, start the cloud-based calibration balancing. If not, do not perform any balancing operation. The above-mentioned first balancing time is calculated and stored when the execution conditions of the top dynamic balancing are met; the second balancing time is calculated and stored when the execution conditions of the middle balancing are met.

[0268] Figure 6 This is a schematic structural diagram of a battery balancing device 60 provided in an embodiment of the present invention, the device comprising:

[0269] A determination module 601 is configured to determine a target balancing mode from a plurality of balancing modes based on battery status information, wherein the battery status information includes battery status information during and / or after charging;

[0270] The balancing module 602 is configured to balance the battery based on the target balancing mode.

[0271] Optionally, the multiple balancing modes include two or more of the following combinations: top static balancing, top dynamic balancing, middle balancing, bottom balancing and cloud-calibrated balancing.

[0272] Optionally, the battery status information includes: the charging voltage of each single cell in the battery and the open circuit voltage of each single cell in the battery; the battery status information satisfies the execution condition of top static balancing if:

[0273] The charging voltage of the target single cell in the battery status information reaches the full charge condition, and the maximum open circuit voltage among the open circuit voltages of the single cells in the battery status information is greater than the first preset open circuit voltage; the target single cell is the single cell with the highest charging voltage.

[0274] Optionally, when determining the target balancing mode from multiple balancing modes based on the battery status information, the determining module 601 is specifically configured to:

[0275] The target balancing mode is determined based on the battery status information and the execution conditions of each balancing mode currently in use; different balancing modes correspond to different execution conditions; the target balancing mode is the balancing mode determined from each balancing mode currently in use when the battery status information meets the corresponding execution conditions.

[0276] Optionally, if top static balancing exists among the currently used balancing modes, the determination module 601 is specifically configured to:

[0277] After battery charging is completed, if it is determined that the battery has a balancing requirement, and the charging voltage of the target single cell in the battery status information reaches the full charging condition, and the maximum open-circuit voltage among the open-circuit voltages of the individual single cells in the battery status information is greater than a first preset open-circuit voltage, then top static balancing is determined as the target balancing mode; the target single cell is the single cell with the highest charging voltage.

[0278] Optionally, when determining that the battery has a balancing requirement, the determining module 601 is specifically configured to:

[0279] When it is determined that the difference between the maximum open circuit voltage and the minimum open circuit voltage among the open circuit voltages corresponding to the individual battery cells is greater than a first preset difference, it is determined that the battery has a balancing requirement.

[0280] Optionally, when balancing the battery based on the target balancing mode, the balancing module 602 is specifically configured to:

[0281] For each single cell, determining the corresponding remaining capacity according to the open circuit voltage of the single cell;

[0282] For each single cell in the battery except a first reference single cell, determining an equalization value for each single cell according to the remaining capacity of the single cell and the remaining capacity of the first reference single cell; wherein the first reference single cell is the single cell with the smallest open circuit voltage among all the single cells when fully charged;

[0283] The single battery cells are balanced according to the balance values of the single battery cells.

[0284] Optionally, when determining the corresponding remaining capacity according to the open circuit voltage of the single battery cell, the balancing module 602 is specifically configured to:

[0285] The remaining capacity corresponding to the open circuit voltage of the single cell is determined according to a preset corresponding relationship; the preset corresponding relationship represents the relationship between the remaining capacity and the open circuit voltage.

[0286] Optionally, if top dynamic balancing is present in the currently used balancing modes, the determination module 601 is further configured to:

[0287] If the maximum open-circuit voltage among the open-circuit voltages of the individual battery cells in the battery status information is less than or equal to the first preset open-circuit voltage, and it is determined that the stored first balancing time is greater than 0, top dynamic balancing is determined as the target balancing mode;

[0288] The first balancing time is calculated and stored after the battery is fully charged and the battery status information satisfies the execution condition of the top dynamic balancing.

[0289] Optionally, the battery status information satisfies the execution conditions of top dynamic balancing:

[0290] The charging voltage of the target single cell in the battery status information reaches the full charging condition and the top static balancing is not started for more than a first preset time.

[0291] Optionally, the device further includes: a first processing module, configured to:

[0292] Obtaining the charging voltage of each single cell when the battery reaches a full charge condition during the charging process, and for any single cell in the battery except the second reference single cell, when the difference between the charging voltage corresponding to the single cell and the charging voltage of the second reference single cell is greater than a second preset difference, storing the identifier of the single cell and the corresponding first balancing time;

[0293] The second reference single cell is a cell with the smallest charging voltage among all the single cells.

[0294] Optionally, the device further includes: a first resetting module, configured to:

[0295] After the top dynamic balancing is determined as the target balancing mode and the battery is balanced, the stored first balancing duration is reset to 0.

[0296] Optionally, if mid-segment balancing still exists in the currently used balancing modes, the determination module 601 is further configured to:

[0297] When the stored first balancing time length is not greater than 0 and the stored second balancing time length is greater than 0, determining the mid-segment balancing as the target balancing mode;

[0298] The second balancing time is calculated and stored when the battery status information meets the execution condition of mid-segment balancing.

[0299] Optionally, the battery status information satisfies the execution conditions of mid-segment balancing:

[0300] During the charging process, the inflection point capacities of at least two single cells detected are valid, and top static balancing or top dynamic balancing is not started for more than a second preset time period;

[0301] The second preset duration is greater than the first preset duration.

[0302] Optionally, the device further includes: a second processing module for

[0303] For any single cell in the battery except a third reference single cell, determining a relative capacity difference of the single cell based on the inflection point capacity of the single cell detected during charging and the inflection point capacity of the third reference single cell; the third reference single cell is the single cell corresponding to the maximum inflection point capacity among all inflection point capacities;

[0304] A second balancing time period corresponding to the single battery cell is determined according to the relative capacity difference, and the identifier of the single battery cell and the corresponding second balancing time period are stored.

[0305] Optionally, the device further includes: a third processing module, configured to:

[0306] Obtaining the inflection point capacity and inflection point capacity confidence corresponding to at least two single battery cells detected during the charging process;

[0307] When the inflection point capacity confidence level is greater than a preset confidence level, it is determined that the inflection point capacity corresponding to the inflection point capacity confidence level is valid.

[0308] Optionally, the device further includes: a second resetting module, configured to:

[0309] The mid-segment balancing is determined as the target balancing mode, and after the battery is balanced, the stored second balancing duration is reset to 0.

[0310] Optionally, if mid-segment balancing exists but top dynamic balancing does not exist among the currently used balancing modes, the determination module 601 is further configured to:

[0311] When the maximum open-circuit voltage among the open-circuit voltages of the individual battery cells in the battery status information is less than or equal to the first preset open-circuit voltage, and it is determined that the stored second balancing time is greater than 0, mid-segment balancing is determined as the target balancing mode;

[0312] The second balancing time is calculated and stored when the battery status information meets the execution condition of mid-segment balancing.

[0313] Optionally, the battery status information satisfies the execution conditions of mid-segment balancing:

[0314] During the charging process, the inflection point capacities of at least two single battery cells detected are valid, and top static balancing is not enabled for more than a second preset time period.

[0315] Optionally, if bottom balancing still exists in the currently used balancing modes, the determination module 601 is further configured to:

[0316] When the stored second balancing time is not greater than 0, if the minimum open-circuit voltage among the open-circuit voltages of each single cell is less than the second preset open-circuit voltage and none of the top static balancing, top dynamic balancing and middle balancing is turned on for more than the third preset time, the bottom balancing is determined as the target balancing mode; the third preset time is greater than the second preset time; the second preset open-circuit voltage is less than the first preset open-circuit voltage.

[0317] Optionally, when balancing the battery based on the target balancing mode, the balancing module 602 is specifically configured to:

[0318] For any single cell in the battery except the fourth reference single cell, when the difference between the open circuit voltage corresponding to the any single cell and the open circuit voltage of the fourth reference single cell is greater than a third preset difference, determining the corresponding remaining capacity according to the open circuit voltage of the any single cell;

[0319] Determining the equilibrium value of each single cell according to the remaining capacity of each single cell and the remaining capacity of the fourth reference single cell; the fourth reference single cell is the single cell with the smallest open circuit voltage among all the single cells in the current state;

[0320] The single battery cells are balanced according to the balance values of the single battery cells.

[0321] Optionally, if bottom balancing exists but mid-balancing does not exist in the currently used balancing modes, the determination module 601 is further configured to:

[0322] When the stored first balancing time is not greater than 0, if the minimum open-circuit voltage among the open-circuit voltages of each single cell is less than the second preset open-circuit voltage and the top static balancing or the top dynamic balancing is not turned on for more than the third preset time, the bottom balancing is determined as the target balancing mode; the third preset time is greater than the first preset time; and the second preset open-circuit voltage is less than the first preset open-circuit voltage.

[0323] Optionally, if cloud-calibrated balancing is also present in the currently used balancing modes, the determination module 601 is further configured to:

[0324] If none of the top static balancing, top dynamic balancing, middle balancing and bottom balancing is turned on for more than a fourth preset time, cloud-calibrated balancing is determined as the target balancing mode; the fourth preset time is longer than the third preset time;

[0325] Accordingly, when balancing the battery based on the target balancing mode, the balancing module 602 is specifically configured to:

[0326] Send a prompt message; the prompt message is used to remind the user to perform AC charging and fully charge to achieve the execution conditions of top static balance, top dynamic balance or mid-section balance.

[0327] Optionally, if cloud-calibrated balancing exists but bottom balancing does not exist in the currently used balancing modes, the determination module 601 is further configured to:

[0328] When the stored second balancing time is not greater than 0, if none of the top static balancing, top dynamic balancing, and mid-segment balancing is enabled for more than a fourth preset time, cloud-calibrated balancing is determined as the target balancing mode; the fourth preset time is greater than the second preset time;

[0329] Accordingly, when balancing the battery based on the target balancing mode, the balancing module 602 is specifically configured to:

[0330] Send a prompt message; the prompt message is used to remind the user to perform AC charging and fully charge to achieve the execution conditions of top static balance, top dynamic balance or mid-section balance.

[0331] Optionally, the device further includes: an acquisition module, configured to:

[0332] After the battery is charged, if the rest time of the battery is greater than the preset rest time, the open circuit voltage of each single cell is obtained.

[0333] Optionally, the priorities of the balancing modes are, from high to low, top static balancing, top dynamic balancing, middle balancing, bottom balancing, and cloud-calibrated balancing. When the determination module 601 determines a target balancing mode from multiple balancing modes based on battery status information, it is specifically configured to:

[0334] Based on the battery status information and the priorities of the currently used balancing modes, the battery status information and the satisfaction of the execution conditions of each balancing mode are judged in descending order of priority until a target balancing mode is determined. Different balancing modes correspond to different execution conditions. The target balancing mode is the balancing mode determined from the currently used balancing modes when the battery status information meets the corresponding execution conditions.

[0335] Optionally, the priorities of the balancing modes are, from high to low, top static balancing, top dynamic balancing, middle balancing, bottom balancing, and cloud-calibrated balancing. When the determination module 601 determines a target balancing mode from multiple balancing modes based on battery status information, it is specifically configured to:

[0336] According to the battery status information and the execution conditions of each balancing mode currently in use, the balancing mode that meets the corresponding execution conditions is selected;

[0337] The balancing mode with the highest priority among the filtered balancing modes is determined as the target balancing mode.

[0338] The battery balancing device provided by the embodiment of the present invention can achieve the above Figure 2 The battery balancing method of the embodiment shown has similar implementation principles and technical effects, which will not be described in detail here.

[0339] Figure 7 Schematic diagram of the hardware structure of a controller provided by an embodiment of the present invention. Figure 7 As shown, the controller provided by this embodiment includes: at least one processor 701 and a memory 702. The processor 701 and the memory 702 are connected via a bus 703.

[0340] During the specific implementation process, at least one processor 701 executes the computer-executable instructions stored in the memory 702, so that the at least one processor 701 executes the method in the above method embodiment.

[0341] The specific implementation process of the processor 701 can be found in the above method embodiment. Its implementation principle and technical effects are similar and will not be repeated here in this embodiment.

[0342] When the battery is used in a vehicle, the controller may be a battery management system (BMS) or a vehicle controller.

[0343] In the above Figure 7 In the illustrated embodiment, it should be understood that the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASICs), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the present invention may be directly executed by a hardware processor or by a combination of hardware and software modules within the processor.

[0344] The memory may include a high-speed RAM memory, and may also include a non-volatile storage NVM, such as at least one disk storage.

[0345] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be classified into address buses, data buses, and control buses. For ease of illustration, the buses in the drawings of this application are not limited to just one bus or just one type of bus.

[0346] An embodiment of the present invention further provides an electrical device, comprising: a battery and a controller, wherein the battery comprises a plurality of single cells; and the controller is configured to execute the method of the above method embodiment.

[0347] An embodiment of the present invention further provides a computer-readable storage medium, in which computer-executable instructions are stored. When a processor executes the computer-executable instructions, the method of the above method embodiment is implemented.

[0348] An embodiment of the present application also provides a computer program product, including a computer program, which implements the method of the above method embodiment when executed by a processor.

[0349] The computer-readable storage medium mentioned above can be implemented by any type of volatile or non-volatile memory device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk, or optical disk. The computer-readable storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0350] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be an integral part of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist in the device as discrete components.

[0351] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0352] The serial numbers of the above embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0353] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal device (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in each embodiment of the present application.

[0354] The above are only preferred embodiments of the present application and do not 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 protection scope of the present application.

Claims

1. A battery balancing method, characterized in that: The method comprises: Determining a target balancing mode from a plurality of balancing modes based on battery status information; wherein the battery status information includes battery status information during and / or after charging; The battery is balanced based on the target balancing mode.

2. The method according to claim 1, characterized in that The multiple balancing modes include two or more of the following combinations: top static balancing, top dynamic balancing, middle balancing, bottom balancing and cloud-level calibrated balancing.

3. The method according to claim 2, characterized in that The battery status information includes: the charging voltage of each single cell in the battery and the open circuit voltage of each single cell in the battery; the battery status information satisfies the execution conditions of top static balancing: The charging voltage of the target single cell in the battery status information reaches the full charge condition, and the maximum open circuit voltage among the open circuit voltages of the single cells in the battery status information is greater than the first preset open circuit voltage; the target single cell is the single cell with the highest charging voltage.

4. The method according to claim 2, characterized in that The target balancing mode is determined from a plurality of balancing modes based on the battery status information, including: The target balancing mode is determined based on the battery status information and the execution conditions of each balancing mode currently in use; different balancing modes correspond to different execution conditions; the target balancing mode is the balancing mode determined from each balancing mode currently in use when the battery status information meets the corresponding execution conditions.

5. The method according to claim 4, characterized in that If top static balancing exists among the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes includes: After battery charging is completed, if it is determined that the battery has a balancing requirement, and the charging voltage of the target single cell in the battery status information reaches the full charging condition, and the maximum open-circuit voltage among the open-circuit voltages of the individual single cells in the battery status information is greater than a first preset open-circuit voltage, then top static balancing is determined as the target balancing mode; the target single cell is the single cell with the highest charging voltage.

6. The method according to claim 5, characterized in that The determining that the battery needs to be balanced includes: When it is determined that the difference between the maximum open circuit voltage and the minimum open circuit voltage among the open circuit voltages corresponding to the individual battery cells is greater than a first preset difference, it is determined that the battery has a balancing requirement.

7. The method according to claim 5, characterized in that Balancing the battery based on the target balancing mode includes: For each single cell, determining the corresponding remaining capacity according to the open circuit voltage of the single cell; For each single cell in the battery except a first reference single cell, determining an equalization value for each single cell according to the remaining capacity of the single cell and the remaining capacity of the first reference single cell; wherein the first reference single cell is the single cell with the smallest open circuit voltage among all the single cells when fully charged; The single battery cells are balanced according to the balance values of the single battery cells.

8. The method according to claim 7, characterized in that Determining the corresponding remaining capacity according to the open circuit voltage of the single battery cell includes: The remaining capacity corresponding to the open circuit voltage of the single battery cell is determined according to a preset corresponding relationship; the preset corresponding relationship represents the relationship between the remaining capacity and the open circuit voltage.

9. The method according to claim 5, characterized in that If top dynamic balancing is still present in the currently used balancing modes, determining a target balancing mode according to battery status information and execution conditions of the currently used balancing modes also includes: If the maximum open-circuit voltage among the open-circuit voltages of the individual battery cells in the battery status information is less than or equal to the first preset open-circuit voltage, and it is determined that the stored first balancing time is greater than 0, top dynamic balancing is determined as the target balancing mode; The first balancing time is calculated and stored after the battery is fully charged and the battery status information satisfies the execution condition of the top dynamic balancing.

10. The method according to claim 9, characterized in that The battery status information meets the execution conditions of top dynamic balancing: The charging voltage of the target single cell in the battery status information reaches the full charging condition and the top static balancing is not started for more than a first preset time.

11. The method according to claim 9, characterized in that The method further comprises: Obtaining the charging voltage of each single cell when the battery reaches a full charge condition during the charging process, and for any single cell in the battery except the second reference single cell, when the difference between the charging voltage corresponding to the single cell and the charging voltage of the second reference single cell is greater than a second preset difference, storing the identifier of the single cell and the corresponding first balancing time; The second reference single cell is a cell with the smallest charging voltage among all the single cells.

12. The method according to claim 9, characterized in that The method further comprises: After the top dynamic balancing is determined as the target balancing mode and the battery is balanced, the stored first balancing duration is reset to 0.

13. The method according to claim 9, characterized in that If mid-segment balancing still exists in the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes also includes: When the stored first balancing time length is not greater than 0 and the stored second balancing time length is greater than 0, determining the mid-segment balancing as the target balancing mode; The second balancing time is calculated and stored when the battery status information meets the execution condition of mid-segment balancing.

14. The method according to claim 13, characterized in that The battery status information meets the execution conditions of mid-segment balancing: During the charging process, the inflection point capacities of at least two single cells detected are valid, and top static balancing or top dynamic balancing is not started for more than a second preset time period; The second preset duration is greater than the first preset duration.

15. The method according to claim 14, characterized in that The method further comprises: For any single cell in the battery except a third reference single cell, determining a relative capacity difference of the single cell based on the inflection point capacity of the single cell detected during charging and the inflection point capacity of the third reference single cell; the third reference single cell is the single cell corresponding to the maximum inflection point capacity among all inflection point capacities; A second balancing time duration corresponding to the single battery cell is determined according to the relative capacity difference, and the identifier of the single battery cell and the corresponding second balancing time duration are stored.

16. The method according to claim 14, characterized in that The method further comprises: Obtaining the inflection point capacity and inflection point capacity confidence corresponding to at least two single battery cells detected during the charging process; When the inflection point capacity confidence level is greater than a preset confidence level, it is determined that the inflection point capacity corresponding to the inflection point capacity confidence level is valid.

17. The method according to claim 13, wherein The method further comprises: The mid-segment balancing is determined as the target balancing mode, and after the battery is balanced, the stored second balancing duration is reset to 0.

18. The method according to claim 5, characterized in that If mid-segment balancing exists in the currently used balancing modes but top dynamic balancing does not exist, determining a target balancing mode according to battery status information and execution conditions of the currently used balancing modes also includes: When the maximum open-circuit voltage among the open-circuit voltages of the individual battery cells in the battery status information is less than or equal to the first preset open-circuit voltage, and it is determined that the stored second balancing time is greater than 0, mid-segment balancing is determined as the target balancing mode; The second balancing time is calculated and stored when the battery status information meets the execution condition of mid-segment balancing.

19. The method according to claim 18, characterized in that The battery status information meets the execution conditions of mid-segment balancing: During the charging process, the inflection point capacities of at least two single battery cells detected are valid, and top static balancing is not enabled for more than a second preset time period.

20. The method according to claim 13, wherein If bottom balancing still exists in the currently used balancing modes, determining the target balancing mode according to the battery status information and the execution conditions of the currently used balancing modes also includes: When the stored second balancing time is not greater than 0, if the minimum open-circuit voltage among the open-circuit voltages of each single cell is less than the second preset open-circuit voltage and none of the top static balancing, top dynamic balancing and middle balancing is turned on for more than the third preset time, the bottom balancing is determined as the target balancing mode; the third preset time is greater than the second preset time; the second preset open-circuit voltage is less than the first preset open-circuit voltage.

21. The method according to claim 20, characterized in that Balancing the battery based on the target balancing mode includes: For any single cell in the battery except the fourth reference single cell, when the difference between the open circuit voltage corresponding to the any single cell and the open circuit voltage of the fourth reference single cell is greater than a third preset difference, determining the corresponding remaining capacity according to the open circuit voltage of the any single cell; Determining the equilibrium value of each single cell according to the remaining capacity of each single cell and the remaining capacity of the fourth reference single cell; the fourth reference single cell is the single cell with the smallest open circuit voltage among all the single cells in the current state; The single battery cells are balanced according to the balance values of the single battery cells.

22. The method according to claim 10, wherein If bottom balancing exists but mid-balancing does not exist in the currently used balancing modes, determining a target balancing mode according to battery status information and execution conditions of the currently used balancing modes also includes: When the stored first balancing time is not greater than 0, if the minimum open-circuit voltage among the open-circuit voltages of each single cell is less than the second preset open-circuit voltage and the top static balancing or the top dynamic balancing is not turned on for more than the third preset time, the bottom balancing is determined as the target balancing mode; the third preset time is greater than the first preset time; and the second preset open-circuit voltage is less than the first preset open-circuit voltage.

23. The method according to claim 20, characterized in that If cloud-calibrated balancing is available in the currently used balancing modes, the target balancing mode is determined based on the battery status information and the execution conditions of the currently used balancing modes, which also includes: If none of the top static balancing, top dynamic balancing, middle balancing and bottom balancing is turned on for more than a fourth preset time, cloud-calibrated balancing is determined as the target balancing mode; the fourth preset time is longer than the third preset time; Accordingly, balancing the battery based on the target balancing mode includes: Send a prompt message; the prompt message is used to remind the user to perform AC charging and fully charge to achieve the execution conditions of top static balance, top dynamic balance or mid-section balance.

24. The method according to claim 14, wherein If cloud-calibrated balancing exists in the currently used balancing modes but bottom balancing does not exist, determining the target balancing mode based on the battery status information and the execution conditions of the currently used balancing modes also includes: When the stored second balancing time is not greater than 0, if none of the top static balancing, top dynamic balancing, and mid-segment balancing is enabled for more than a fourth preset time, cloud-calibrated balancing is determined as the target balancing mode; the fourth preset time is greater than the second preset time; Accordingly, balancing the battery based on the target balancing mode includes: Send a prompt message; the prompt message is used to remind the user to perform AC charging and fully charge to achieve the execution conditions of top static balance, top dynamic balance or mid-section balance.

25. The method according to any one of claims 5 to 24, characterized in that The method further comprises: After the battery is charged, if the rest time of the battery is greater than the preset rest time, the open circuit voltage of each single cell is obtained.

26. The method according to claim 2, characterized in that The priorities of the balancing modes from high to low are: top static balancing, top dynamic balancing, middle balancing, bottom balancing, and cloud-calibrated balancing. The target balancing mode is determined from multiple balancing modes based on the battery status information, including: Based on the battery status information and the priorities of the currently used balancing modes, the battery status information and the satisfaction of the execution conditions of each balancing mode are judged in descending order of priority until a target balancing mode is determined. Different balancing modes correspond to different execution conditions. The target balancing mode is the balancing mode determined from the currently used balancing modes when the battery status information meets the corresponding execution conditions.

27. The method according to claim 2, wherein The priorities of the balancing modes from high to low are: top static balancing, top dynamic balancing, middle balancing, bottom balancing, and cloud-calibrated balancing. The target balancing mode is determined from multiple balancing modes based on the battery status information, including: According to the battery status information and the execution conditions of each balancing mode currently in use, the balancing mode that meets the corresponding execution conditions is selected; The balancing mode with the highest priority among the filtered balancing modes is determined as the target balancing mode.

28. A battery balancing device, characterized in that: The device comprises: a determination module, configured to determine a target balancing mode from a plurality of balancing modes based on battery status information; wherein the battery status information includes battery status information during charging and / or after charging; A balancing module is configured to balance the battery based on the target balancing mode.

29. A controller, characterized in that: include: at least one processor and memory; The memory stores computer-executable instructions; The at least one processor executes the computer-executable instructions stored in the memory, so that the at least one processor performs the method according to any one of claims 1 to 27.

30. An electrical device, characterized in that: include: A battery and a controller, wherein the battery comprises a plurality of single cells; The controller is configured to execute the method according to any one of claims 1 to 27.

31. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, and when a processor executes the computer-executable instructions, the method according to any one of claims 1 to 27 is implemented.

32. A computer program product, characterized in that The method comprises a computer program, which implements the method according to any one of claims 1 to 27 when executed by a processor.

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