Battery cell equalization processing method and device, electronic equipment and readable storage medium

Abstract

The invention provides a battery cell equalization processing method and device, electronic equipment and a readable storage medium, and the method comprises the steps: collecting a battery cell voltage value and a battery cell current value of each battery cell in a target battery at a current sampling moment; determining the minimum battery cell voltage value from the battery cell voltage values collected at the current sampling moment, and taking the battery cell corresponding to the minimum battery cell voltage value as a reference battery cell; searching a candidate battery cell voltage value smaller than or equal to the minimum battery cell voltage value from the battery cell voltage values collected by other battery cells at each historical sampling moment; determining a target historical sampling moment closest to the current sampling moment according to the historical sampling moment corresponding to each candidate cell voltage value; and according to the current value of each battery cell from the target historical sampling moment to the current sampling moment and the current value of the battery cell at the current sampling moment, calculating the electric quantity difference between other battery cells and the reference battery cell. Through the method, the accuracy of determining the difference between the electric quantities of the battery cells is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a method, device, electronic device and readable storage medium for processing battery cell balancing. Background Art

[0002] Batteries (such as lithium iron phosphate batteries) generally contain multiple single cells, and the capacity of each cell varies during the manufacturing process. For example, the production standard is to produce a cell with a capacity of 10000mA, but the capacity of the cell actually manufactured may be 10003mA or 99996mA. During the use of the battery, due to the difference in the self-discharge rate of different cells in the battery, the power (remaining power) of each cell after a period of use is different.

[0003] In this case, if the battery is charged, the cell with the most power will generally be fully charged first. If the battery continues to be charged, it will cause overcharge and damage to the cell. Therefore, it is necessary to stop charging the battery at this time. However, other cells with less power in the battery may not be fully charged yet.

[0004] When discharging a battery, the cell with the least power will generally be discharged first. If the battery continues to be discharged, it will cause over-discharge of the cell and damage the cell. Therefore, it is necessary to stop discharging the battery. However, other cells with more power in the battery may not have been fully discharged.

[0005] Therefore, it is necessary to balance the cells in the battery to ensure that the power of each single cell in the battery tends to be consistent, so as to ensure that each cell maintains the same state during normal use, thereby avoiding overcharging or over-discharging.

[0006] Before performing cell balancing on the cells in the battery, it is necessary to determine the difference between the electric quantities of the cells in the battery. Therefore, in the prior art, there is an urgent need for a method for determining the difference between the electric quantities of the cells in the battery. Summary of the invention

[0007] In view of this, the purpose of the present application is to provide a method, device, electronic device and readable storage medium for processing battery cell balancing, so as to improve the accuracy of determining the difference between the power levels of various battery cells in a battery.

[0008] In a first aspect, an embodiment of the present application provides a method for processing cell balancing, including:

[0009] During the charging process of the target battery, for each battery cell in the target battery, the battery cell voltage value and the battery cell current value of the battery cell at the current sampling time are collected;

[0010] If it is detected at the current sampling time that the target battery is in a floating charge state, a minimum cell voltage value is determined from the cell voltage values ​​of the cells collected at the current sampling time, and the cell corresponding to the minimum cell voltage value is used as a reference cell;

[0011] For the nth other battery cell except the reference battery cell, a candidate battery cell voltage value less than or equal to the minimum battery cell voltage value is found for the nth other battery cell from the battery cell voltage values ​​collected by the nth other battery cell at each historical sampling moment; the historical sampling moment is a sampling moment before the current sampling moment among the sampling moments in this charging process; when the total number of other battery cells is 1, n is 1; when the total number of other battery cells is greater than or equal to 2, n is a positive integer from 1 to N in sequence, and N is the total number of other battery cells;

[0012] Determine, for the nth other battery cell, a target historical sampling time closest to the current sampling time according to the historical sampling time corresponding to the candidate battery cell voltage value of the nth other battery cell;

[0013] Based on the battery cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the battery cell current value at the current sampling moment, calculate the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment, so as to use the charging capacity as the charge difference between the nth other battery cell and the reference battery cell.

[0014] In combination with the first aspect, an embodiment of the present application provides a first possible implementation of the first aspect, wherein there are a preset number of sub-sampling moments between two adjacent sampling moments; and collecting the cell voltage value and the cell current value of the cell at the current sampling moment includes:

[0015] Collect the current cell voltage value and cell current value of the cell at the current sampling time;

[0016] For each sub-sampling time between the current sampling time and the previous sampling time adjacent to the current sampling time, collecting the current cell current value of the cell at the sub-sampling time;

[0017] Calculate the cell current value at the current sampling moment and the average value of each cell current value collected at each sub-sampling moment between the current sampling moment and the previous sampling moment, and use the average value as the final cell current value of the cell at the current sampling moment.

[0018] In combination with the first aspect or the first possible implementation manner of the first aspect, the embodiment of the present application provides a second possible implementation manner of the first aspect, wherein a preset time length is separated between two adjacent sampling moments, and the calculation of the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment according to the battery cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the battery cell current value at the current sampling moment, includes:

[0019] For each sampling moment between the target historical sampling moment and the current sampling moment, calculate the product of the cell current value collected at the sampling moment and the preset time length, and calculate the product of the cell current value at the current sampling moment and the preset time length;

[0020] Calculate the product corresponding to each sampling moment between the target historical sampling moment and the current sampling moment, and the sum of the products corresponding to the current sampling moment, to obtain the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment.

[0021] In combination with the first aspect, the embodiment of the present application provides a third possible implementation of the first aspect, wherein each of the other battery cells is respectively connected to a balancing resistor, and the method further includes:

[0022] For each of the other cells, the target balancing time of the other cells is calculated by the following formula:

[0023]

[0024] Among them, I bal Characterizes the balancing current value of the other cells; R bal Characterizes the resistance value of the balancing resistor corresponding to the other battery cell; the balancing resistor is used to convert the electrical energy in the other battery cell into heat energy to consume the power of the other battery cell; V bal Characterizes the cell plateau voltage value of the other cell, V bal The value range is 3200mv-3300mv;

[0025]

[0026] Among them, T bal Characterizes the target balancing time of the other battery cell; DiffCapx characterizes the difference in charge between the other battery cell and the reference battery cell; Ratio is a constant greater than 0 and less than 1.

[0027] In combination with the third possible implementation of the first aspect, the embodiment of the present application provides a fourth possible implementation of the first aspect, wherein the method further includes:

[0028] For each of the other cells, in the process of performing cell balancing on the other cells through the balancing resistor corresponding to the other cells, detecting in real time the balanced cell voltage value of the other cells during cell balancing;

[0029] If the current balancing time of the other battery cells does not reach the target balancing time of the other battery cells, and the current balancing battery cell voltage value of the other battery cells is equal to the first battery cell voltage value, then the battery cell balancing of the other battery cells is stopped; the first battery cell voltage value is the difference between the minimum battery cell voltage value and the preset voltage value;

[0030] If the current balancing time of the other battery cell reaches the target balancing time of the other battery cell, and the current balancing battery cell voltage value of the other battery cell is greater than the first battery cell voltage value, then the battery cell balancing of the other battery cell is stopped.

[0031] In a second aspect, an embodiment of the present application further provides a cell balancing processing device, comprising:

[0032] The acquisition module is used to collect the cell voltage value and the cell current value of each cell in the target battery at the current sampling time during the charging process of the target battery;

[0033] A first determination module is used to determine a minimum cell voltage value from the cell voltage values ​​of the cells collected at the current sampling moment if it is detected that the target battery is in a floating charge state at the current sampling moment, so as to use the cell corresponding to the minimum cell voltage value as a reference cell;

[0034] A search module, for searching, for the nth other battery cell except the reference battery cell, a candidate battery cell voltage value that is less than or equal to the minimum battery cell voltage value from the battery cell voltage values ​​collected by the nth other battery cell at each historical sampling moment; the historical sampling moment is a sampling moment before the current sampling moment among the sampling moments in this charging process; when the total number of other battery cells is 1, n is 1; when the total number of other battery cells is greater than or equal to 2, n is a positive integer from 1 to N in sequence, and N is the total number of other battery cells;

[0035] A second determination module is used to determine a target historical sampling time closest to the current sampling time for the nth other battery cell according to the historical sampling time corresponding to the candidate battery cell voltage value of the nth other battery cell;

[0036] The first calculation module is used to calculate the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment based on the battery cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the battery cell current value at the current sampling moment, so as to use the charging capacity as the charge difference between the nth other battery cell and the reference battery cell.

[0037] In combination with the second aspect, an embodiment of the present application provides a first possible implementation of the second aspect, wherein there is a preset number of sub-sampling moments between two adjacent sampling moments; when the acquisition module is used to collect the cell voltage value and the cell current value of the cell at the current sampling moment, it is specifically used to:

[0038] Collect the cell voltage value and cell current value of the cell at the current sampling time;

[0039] For each sub-sampling time between the current sampling time and the previous sampling time adjacent to the current sampling time, collecting the current cell current value of the cell at the sub-sampling time;

[0040] Calculate the cell current value at the current sampling moment and the average value of each cell current value collected at each sub-sampling moment between the current sampling moment and the previous sampling moment, and use the average value as the final cell current value of the cell at the current sampling moment.

[0041] In combination with the second aspect or the first possible implementation manner of the second aspect, the embodiment of the present application provides a second possible implementation manner of the second aspect, wherein the interval between two adjacent sampling moments is a preset time length, and the first calculation module is used to calculate the charging power of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment according to the battery cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the battery cell current value at the current sampling moment, specifically for:

[0042] For each sampling moment between the target historical sampling moment and the current sampling moment, calculate the product of the cell current value collected at the sampling moment and the preset time length, and calculate the product of the cell current value at the current sampling moment and the preset time length;

[0043] Calculate the product corresponding to each sampling moment between the target historical sampling moment and the current sampling moment, and the sum of the products corresponding to the current sampling moment, to obtain the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment.

[0044] In combination with the second aspect, the embodiment of the present application provides a third possible implementation of the second aspect, wherein each of the other battery cells is respectively connected to a balancing resistor, and the device further includes:

[0045] The second calculation module is used to calculate the target balancing time of each of the other cells by using the following formula:

[0046]

[0047] Among them, I bal Characterizes the balancing current value of the other cells; R bal Characterizes the resistance value of the balancing resistor corresponding to the other battery cell; the balancing resistor is used to convert the electrical energy in the other battery cell into heat energy to consume the power of the other battery cell; V bal Characterizes the cell plateau voltage value of the other cell, V bal The value range is 3200mv-3300mv;

[0048]

[0049] Among them, T bal Characterizes the target balancing time of the other battery cell; DiffCapx characterizes the difference in charge between the other battery cell and the reference battery cell; Ratio is a constant greater than 0 and less than 1.

[0050] In combination with the third possible implementation of the second aspect, the embodiment of the present application provides a fourth possible implementation of the second aspect, wherein the device further includes:

[0051] A detection module, configured to detect in real time, for each of the other cells, a balanced cell voltage value of the other cell during cell balancing in the process of performing cell balancing on the other cell through the balancing resistor corresponding to the other cell;

[0052] A first stop module is used to stop cell balancing for the other battery cells if the current balancing time of the other battery cells does not reach the target balancing time of the other battery cells and the current balancing cell voltage value of the other battery cells is equal to the first cell voltage value; the first cell voltage value is the difference between the minimum cell voltage value and the preset voltage value;

[0053] The second stopping module is used for stopping cell balancing for the other cell if the current balancing time of the other cell reaches the target balancing time of the other cell and the current balancing cell voltage value of the other cell is greater than the first cell voltage value.

[0054] In a third aspect, an embodiment of the present application further provides an electronic device, comprising: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and when the machine-readable instructions are executed by the processor, the steps in any possible implementation of the first aspect above are performed.

[0055] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of any possible implementation of the first aspect described above are executed.

[0056] The embodiments of the present application provide a method, device, electronic device and readable storage medium for processing cell balancing, wherein, during the charging process of a target battery, for each cell in the target battery, the cell voltage value and the cell current value of the cell at the current sampling moment are collected; if it is detected that the target battery is in a floating charge state at the current sampling moment, the minimum cell voltage value is determined from the cell voltage values ​​of the cells collected at the current sampling moment, and the cell corresponding to the minimum cell voltage value is used as a reference cell; for the nth cell other than the reference cell, the cell current value of the nth cell at each historical sampling moment is used as the reference cell; Among the cell voltage values ​​collected at the historical sampling moments, find a candidate cell voltage value that is less than or equal to the minimum cell voltage value for the nth other cell; the historical sampling moment is the sampling moment before the current sampling moment among the sampling moments in this charging process; when the total number of other cells is 1, n is 1; when the total number of other cells is greater than or equal to 2, n is a positive integer from 1 to N, where N is the total number of other cells; based on the historical sampling moments corresponding to the candidate cell voltage values ​​of the nth other cell, determine the target historical sampling moment closest to the current sampling moment for the nth other cell. At this point, the target historical sampling moment of the nth other cell determined represents that the power of the nth other cell at the target historical sampling moment is close to the power of the reference cell at the current sampling moment. That is to say, the amount of electricity charged by the nth other battery cell during the period from the target historical sampling moment to the current sampling moment is more than the amount of electricity charged by the reference battery cell at the current sampling moment. Therefore, the amount of electricity charged by the nth other battery cell during the period between the target historical sampling moment and the current sampling moment is calculated based on the battery cell current value collected at each sampling moment from the target historical sampling moment to the current sampling moment and the battery cell current value at the current sampling moment, so as to use the charged electricity as the difference in electricity between the nth other battery cell and the reference battery cell. The difference in electricity between the electricity of each battery cell in the target battery determined in the above manner is more accurate.

[0057] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0059] Figure 1 A flow chart of a cell balancing processing method provided in an embodiment of the present application is shown;

[0060] Figure 2 A schematic diagram showing the corresponding relationship between each sampling time, battery cell voltage value, and battery cell current value provided in an embodiment of the present application;

[0061] Figure 3 A schematic diagram showing a sub-sampling time between two adjacent sampling times provided in an embodiment of the present application is shown;

[0062] Figure 4 A schematic diagram of the structure of a cell balancing processing device provided in an embodiment of the present application is shown;

[0063] Figure 5 A schematic structural diagram of an electronic device provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0064] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0065] In the prior art, the power difference between cells is generally determined by the voltage difference between cells. However, the cell plateau period in a battery (such as a lithium iron phosphate battery) is relatively long, and the voltage difference between cells is very small during the plateau period, so it is difficult to determine the power difference between cells by the voltage difference. When using the battery open circuit voltage OCV table to determine the power difference between cells, the battery needs to be left at rest for several hours, which wastes time. Moreover, as the battery (such as a lithium iron phosphate battery) is used, the accuracy of the open circuit voltage OCV table becomes lower and lower, and the error of the determined power difference becomes larger and larger.

[0066] In view of the above problems, based on this, the embodiments of the present application provide a method, device, electronic device and readable storage medium for processing battery cell balancing, which are described below through embodiments.

[0067] To facilitate understanding of this embodiment, a cell balancing processing method disclosed in an embodiment of the present application is first introduced in detail. Figure 1 A flow chart of a cell balancing processing method provided in an embodiment of the present application is shown, such as Figure 1 As shown, the following steps S101-S105 are included:

[0068] S101: During the charging process of the target battery, for each battery cell in the target battery, a battery cell voltage value and a battery cell current value of the battery cell at a current sampling time are collected.

[0069] In this embodiment, the target battery may be a lithium iron phosphate battery, and the target battery includes a plurality of cells. During the charging process of the target battery, the cell voltage value and the cell current value at each sampling time interval of a preset time within the latest hour are continuously recorded. The current sampling time refers to the current sampling time.

[0070] For example, the battery cells A and B in the target battery are used as an example for explanation. Figure 2 A schematic diagram showing the corresponding relationship between each sampling time, cell voltage value, and cell current value provided in the embodiment of the present application is shown as follows: Figure 2 As shown, t1-t6 are the sampling moments, wherein t6 is the current sampling moment, t1-t5 are the historical sampling moments, Va6 is the cell voltage value of cell A at the current sampling moment t6, Ia6 is the cell current value of cell A at the current sampling moment t6, Vb6 is the cell voltage value of cell B at the current sampling moment t6, and Ib6 is the cell current value of cell B at the current sampling moment t6.

[0071] In a possible implementation, there are a preset number of sub-sampling moments between two adjacent sampling moments; when executing step S101 to collect the cell voltage value and the cell current value of the cell at the current sampling moment, the following steps may be specifically performed:

[0072] S1011: Collect the cell voltage value and the cell current value of the cell at the current sampling moment.

[0073] S1012: For each sub-sampling time between the current sampling time and the previous sampling time adjacent to the current sampling time, collect the cell current value of the cell at the sub-sampling time.

[0074] S1013: Calculate the cell current value at the current sampling moment and the average value of each cell current value collected at each sub-sampling moment between the current sampling moment and the previous sampling moment, and use the average value as the final cell current value of the cell at the current sampling moment.

[0075] Figure 3 A schematic diagram of a sub-sampling time between two adjacent sampling times provided in an embodiment of the present application is shown, such as Figure 3 As shown, taking two adjacent sampling moments t5 and t6 as an example, there are four sub-sampling moments between the sampling moment t5 and the sampling moment t6, namely, sub-sampling moments t5.1, t5.2, t5.3, and t5.4.

[0076] When executing step S1012, illustratively, the current sampling time is t6, the previous sampling time adjacent to the current sampling time is t5, and the sub-sampling times between the current sampling time t6 and the previous sampling time t5 are t5.1, t5.2, t5.3, and t5.4, respectively. The cell current values ​​of cell A at each sub-sampling time are collected, which are Ia5.1, Ia5.2, Ia5.3, and Ia5.4, respectively. And the cell current values ​​of cell B at each sub-sampling time are collected, which are Ib5.1, Ib5.2, Ib5.3, and Ib5.4, respectively.

[0077] When executing step S1013, illustratively, for battery cell A, the average value of the battery cell current value Ia6 at the current sampling time t6 and the battery cell current values ​​Ia5.1, Ia5.2, Ia5.3, and Ia5.4 at each sub-sampling time is calculated, and the average value is used as the final battery cell current value of battery cell A at the current sampling time t6.

[0078] S102: If it is detected at the current sampling time that the target battery is in a floating charge state, a minimum cell voltage value is determined from the cell voltage values ​​of the cells collected at the current sampling time, and the cell corresponding to the minimum cell voltage value is used as a reference cell.

[0079] In this embodiment, when the target battery has been in a charging state for a certain recent period of time and the target battery is in a floating charge state at the current sampling moment, the calculation of the power generation difference is triggered. Among them, the floating charge state means that the target battery is almost fully charged, but still continues to be charged with a small current value. Being almost fully charged specifically means that the SOC of the target battery reaches a preset percentage, and the value range of the preset percentage can be 90%-98%.

[0080] At this time, the minimum cell voltage value is determined from the cell voltage values Va6 and Vb6 of each cell collected at the current sampling moment t6. For example, if Va6 is less than Vb6, then Va6 is the minimum cell voltage value, and the cell A corresponding to Va6 is used as the reference cell.

[0081] S103: For the nth other cell except the reference cell, a candidate cell voltage value less than or equal to the minimum cell voltage value is found from the cell voltage values collected by the nth other cell at each historical sampling moment; the historical sampling moment is the sampling moment before the current sampling moment in each sampling moment during this charging process; when the total number of other cells is 1, n is 1; when the total number of other cells is greater than or equal to 2, n takes positive integers from 1 to N in sequence, and N is the total number of other cells.

[0082] In this embodiment, since the target battery has been in a charging state, the电量 in cell B gradually increases with the passage of charging time, which also makes the cell voltage value of cell B gradually increase with the passage of charging time. Therefore, the magnitude relationship between the cell voltage values of cell B collected at each sampling moment t1 - t6 is: Vb1 < Vb2 < Vb3 < Vb4 < Vb5 < Vb6.

[0083] For the nth other cell B, a candidate cell voltage value less than or equal to the minimum cell voltage value is found from the cell voltage values Vb1, Vb2, Vb3, Vb4, Vb5 collected by the nth other cell B at each historical sampling moment (t1 - t5). For example, if the cell voltage values Vb1 < Vb2 < Vb3 ≤ Va6 < Vb4 < Vb5 < Vb6, then Vb1, Vb2, Vb3 are the candidate cell voltage values of the nth other cell B.

[0084] In this embodiment, this charging process starts to be calculated when the target battery is connected to the charging power supply this time.

[0085] S104: According to the historical sampling moment corresponding to the candidate cell voltage value of the nth other cell, the target historical sampling moment closest to the current sampling moment is determined for the nth other cell.

[0086] In this embodiment, the historical sampling time of the candidate cell voltage value Vb1 of the nth other battery cell B is t1, the historical sampling time of the candidate cell voltage value Vb2 is t2, and the historical sampling time of the candidate cell voltage value Vb3 is t3, wherein the historical sampling time t3 is closest to the current sampling time t6, and therefore, the historical sampling time t3 is the target historical sampling time of the nth other battery cell B.

[0087] S105: Calculate the charging capacity of the nth other battery cell in the time period between the target historical sampling time and the current sampling time based on the battery cell current value collected at each sampling time between the target historical sampling time and the current sampling time, and use the charging capacity as the charge difference between the nth other battery cell and the reference battery cell.

[0088] In this embodiment, the nth other cell is described as cell B. Since the cell voltage value Vb3 of cell B at the target historical sampling time t3 is close to the cell voltage value Va6 of reference cell A at the current sampling time t6, it is considered that during the charging process, the power of cell B at the target historical sampling time t3 is close to the power of reference cell A at the current sampling time t6. Then, the power charged to cell B during the period from the target historical sampling time t3 to the current sampling time t6 is equivalent to the extra power of cell B over cell A at the current sampling time t6.

[0089] In this embodiment, the charge capacity of cell B in the period between the target historical sampling time t3 and the current sampling time t6 can be calculated based on each sampling time (t4, t5) between the target historical sampling time t3 and the current sampling time t6, and the cell current value (Ib4, Ib5, Ib6) collected by cell B at the current sampling time (t6), so as to use the charge capacity as the capacity difference between cell B and reference cell A. In other words, the capacity difference between other cells and the reference cell refers to the excess capacity of other cells compared with the reference cell.

[0090] In a possible implementation manner, a preset time interval is set between two adjacent sampling moments. When executing step S105, the following steps may be specifically performed:

[0091] S1051: For each sampling moment between the target historical sampling moment and the current sampling moment, the product of the cell current value collected at the sampling moment and the preset time length is calculated, and the product of the cell current value at the current sampling moment and the preset time length is calculated.

[0092] S1052: Calculate the product corresponding to each sampling moment between the target historical sampling moment and the current sampling moment, and the sum of the products corresponding to the current sampling moment, to obtain the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment.

[0093] For example, Figure 2 As shown, the sampling moments t1-t2 are separated by a preset time length T, and the sampling moments t2-t3, t3-t4, t4-t5, and t5-t6 are also separated by a preset time length T.

[0094] When executing step S1051, take the nth other battery cell as battery cell B as an example, for each sampling time (t4, t5) between the target historical sampling time t3 and the current sampling time t6, calculate the product Ib4' of the battery cell current value Ib4 collected at the sampling time t4 and the preset time length T, and the product Ib5' of the battery cell current value Ib5 collected at the sampling time t5 and the preset time length T. And calculate the product Ib6' of the battery cell current value Ib6 at the current sampling time t6 and the preset time length T.

[0095] When executing step S1052, the sum of the products Ib4', Ib5', and Ib6' corresponding to the sampling times t4, t5, and t6 is calculated, that is, the sum = Ib4'+Ib5'+Ib6'. The sum is used as the charge capacity of the battery cell B during the period between the target historical sampling time t3 and the current sampling time t6. The calculated charge capacity is used as the excess capacity of the battery cell B over the reference battery cell A at the current sampling time t6, that is, the capacity difference between the battery cell B and the reference battery cell A.

[0096] In one possible implementation, after determining the difference in charge between other battery cells and a reference battery cell, it is necessary to perform battery balancing on the other battery cells, that is, it is necessary to reduce the charge in the other battery cells. In this embodiment, battery balancing on the other battery cells can be performed by consuming the charge in the other battery cells (e.g., discharging), thereby reducing the difference between the charge of the other battery cells and the charge of the reference battery cell.

[0097] When performing cell balancing on other cells, it is necessary to first determine the balancing time of other cells, that is, it is necessary to first determine the discharge time of other cells. In this embodiment, each other cell is connected to a balancing resistor, and for each other cell, the target balancing time of the other cell is calculated by the following formula:

[0098]

[0099] Among them, I bal Characterizes the balancing current value of the other cells; R balCharacterizes the resistance value of the balancing resistor corresponding to the other battery cell; the balancing resistor is used to convert the electrical energy in the other battery cell into heat energy to consume the power of the other battery cell; V bal Characterizes the cell plateau voltage value of the other cell, V bal The value range is 3200mv-3300mv;

[0100]

[0101] Among them, T bal Characterizes the target balancing time of the other battery cells; DiffCapx characterizes the difference in charge between the other battery cells and the reference battery cells; Ratio is a constant greater than 0 and less than 1.

[0102] In this embodiment, when other battery cells are balanced (eg, discharged), the other battery cells are used to provide electrical energy to a balancing resistor connected to the other battery cells, and the balancing resistor is used to convert the electrical energy into heat energy to consume the electricity in the other battery cells.

[0103] In a possible implementation, in the process of using a balancing resistor to balance other battery cells, since when collecting the battery current value or the battery voltage value of other battery cells, the collected battery voltage value may be inaccurate, which will make the calculated balancing time inaccurate. Therefore, it is possible that the power in other battery cells is already close to that of the reference battery cell before the balancing time is reached. At this time, if the other battery cells continue to be balanced, the power of the other battery cells will be smaller than that of the reference battery cell, and the difference will become larger and larger.

[0104] Considering the above problems, in this embodiment, the following steps S1061-S1063 can also be performed:

[0105] S1061: For each other cell, in the process of performing cell balancing on the other cell through the balancing resistor corresponding to the other cell, a balanced cell voltage value of the other cell during cell balancing is detected in real time.

[0106] S1062: If the current balancing time of the other battery cells does not reach the target balancing time of the other battery cells, and the current balancing battery cell voltage value of the other battery cells is equal to the first battery cell voltage value, then stop balancing the battery cells of the other battery cells; the first battery cell voltage value is the difference between the minimum battery cell voltage value and the preset voltage value.

[0107] In this embodiment, if the current balanced cell voltage value of the other cell drops to the first cell voltage value, it means that the amount of electricity in the other cell is not much different from that in the reference cell.

[0108] The first cell voltage value = the minimum cell voltage value - the preset voltage value; the minimum cell voltage value is greater than the preset voltage value. For example, when the preset voltage value is 3mV and the minimum cell voltage value Va6 is 2000mV, the first cell voltage value is 1997mV.

[0109] S1063: If the current balancing time of the other battery cell reaches the target balancing time of the other battery cell, and the current balancing battery cell voltage value of the other battery cell is greater than the first battery cell voltage value, stop performing battery cell balancing on the other battery cell.

[0110] In this embodiment, if the balanced cell voltage value of the other cell is always greater than the first cell voltage value during the entire balancing time, it means that the power of the other cell is always greater than the power of the reference cell during the entire balancing time. At this time, cell balancing is performed on the other cell during the entire balancing time, which can reduce the difference in power between the other cell and the reference cell.

[0111] Based on the same technical concept, the present application also provides a cell balancing processing device, Figure 4 A schematic diagram of the structure of a cell balancing processing device provided in an embodiment of the present application is shown. Figure 4 As shown, the device comprises:

[0112] The acquisition module 401 is used to collect the cell voltage value and the cell current value of each cell in the target battery at the current sampling time during the charging process of the target battery;

[0113] A first determination module 402 is configured to determine a minimum cell voltage value from the cell voltage values ​​of the cells collected at the current sampling moment if the target battery is detected to be in a floating charge state at the current sampling moment, and use the cell corresponding to the minimum cell voltage value as a reference cell;

[0114] A search module 403 is used to search for a candidate cell voltage value that is less than or equal to the minimum cell voltage value for the nth other cell except the reference cell from the cell voltage values ​​collected by the nth other cell at each historical sampling moment; the historical sampling moment is a sampling moment before the current sampling moment in each sampling moment in this charging process; when the total number of other cells is 1, n is 1; when the total number of other cells is greater than or equal to 2, n is a positive integer from 1 to N in sequence, and N is the total number of other cells;

[0115] A second determination module 404 is used to determine a target historical sampling time closest to the current sampling time for the nth other battery cell according to the historical sampling time corresponding to the candidate battery cell voltage value of the nth other battery cell;

[0116] The first calculation module 405 is used to calculate the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment based on the battery cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the battery cell current value at the current sampling moment, so as to use the charging capacity as the charge difference between the nth other battery cell and the reference battery cell.

[0117] Optionally, there is a preset number of sub-sampling moments between two adjacent sampling moments; when the acquisition module 401 is used to collect the cell voltage value and the cell current value of the cell at the current sampling moment, it is specifically used to:

[0118] Collect the cell voltage value and cell current value of the cell at the current sampling time;

[0119] For each sub-sampling time between the current sampling time and the previous sampling time adjacent to the current sampling time, collecting the current cell current value of the cell at the sub-sampling time;

[0120] Calculate the cell current value at the current sampling moment and the average value of each cell current value collected at each sub-sampling moment between the current sampling moment and the previous sampling moment, and use the average value as the final cell current value of the cell at the current sampling moment.

[0121] Optionally, a preset time interval is set between two adjacent sampling moments, and the first calculation module 405 is used to calculate the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment according to the battery cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the battery cell current value at the current sampling moment, specifically for:

[0122] For each sampling moment between the target historical sampling moment and the current sampling moment, calculate the product of the cell current value collected at the sampling moment and the preset time length, and calculate the product of the cell current value at the current sampling moment and the preset time length;

[0123] Calculate the product corresponding to each sampling moment between the target historical sampling moment and the current sampling moment, and the sum of the products corresponding to the current sampling moment, to obtain the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment.

[0124] Optionally, each of the other cells is respectively connected to a balancing resistor, and the device further comprises:

[0125] The second calculation module is used to calculate the target balancing time of each of the other cells by using the following formula:

[0126]

[0127] Among them, I bal Characterizes the balancing current value of the other cells; R bal Characterizes the resistance value of the balancing resistor corresponding to the other battery cell; the balancing resistor is used to convert the electrical energy in the other battery cell into heat energy to consume the power of the other battery cell; V bal Characterizes the cell plateau voltage value of the other cell, V bal The value range is 3200mv-3300mv;

[0128]

[0129] Among them, T bal Characterizes the target balancing time of the other battery cell; DiffCapx characterizes the difference in charge between the other battery cell and the reference battery cell; Ratio is a constant greater than 0 and less than 1.

[0130] Optionally, the device further comprises:

[0131] A detection module, configured to detect in real time, for each of the other cells, a balanced cell voltage value of the other cell during cell balancing in the process of performing cell balancing on the other cell through the balancing resistor corresponding to the other cell;

[0132] A first stop module is used to stop cell balancing for the other battery cells if the current balancing time of the other battery cells does not reach the target balancing time of the other battery cells and the current balancing cell voltage value of the other battery cells is equal to the first cell voltage value; the first cell voltage value is the difference between the minimum cell voltage value and the preset voltage value;

[0133] The second stopping module is used for stopping cell balancing for the other cell if the current balancing time of the other cell reaches the target balancing time of the other cell and the current balancing cell voltage value of the other cell is greater than the first cell voltage value.

[0134] Figure 5 A structural diagram of an electronic device provided for an embodiment of the present application includes: a processor 501, a memory 502 and a bus 503, wherein the memory 502 stores machine-readable instructions executable by the processor 501. When the electronic device runs the above-mentioned information processing method, the processor 501 communicates with the memory 502 through the bus 503, and the processor 501 executes the machine-readable instructions to perform the method steps described in Example 1.

[0135] The embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the method steps described in the first embodiment are executed.

[0136] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices, electronic devices, and computer-readable storage media can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0137] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some communication interface, device or unit, which can be electrical, mechanical or other forms.

[0138] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0139] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0140] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0141] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for processing battery cell balancing, characterized in that: include: During the charging process of the target battery, for each battery cell in the target battery, the battery cell voltage value and the battery cell current value of the battery cell at the current sampling time are collected; If it is detected at the current sampling time that the target battery is in a floating charge state, a minimum cell voltage value is determined from the cell voltage values ​​of the cells collected at the current sampling time, and the cell corresponding to the minimum cell voltage value is used as a reference cell; For the nth other battery cell except the reference battery cell, a candidate battery cell voltage value less than or equal to the minimum battery cell voltage value is found for the nth other battery cell from the battery cell voltage values ​​collected by the nth other battery cell at each historical sampling moment; the historical sampling moment is a sampling moment before the current sampling moment among the sampling moments in this charging process; when the total number of other battery cells is 1, n is 1; when the total number of other battery cells is greater than or equal to 2, n is a positive integer from 1 to N in sequence, and N is the total number of other battery cells; Determine, for the nth other battery cell, a target historical sampling time closest to the current sampling time according to the historical sampling time corresponding to the candidate battery cell voltage value of the nth other battery cell; Based on the battery cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the battery cell current value at the current sampling moment, calculate the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment, so as to use the charging capacity as the charge difference between the nth other battery cell and the reference battery cell.

2. The method according to claim 1, characterized in that: There are a preset number of sub-sampling moments between two adjacent sampling moments; the collecting of the cell voltage value and the cell current value of the cell at the current sampling moment includes: Collect the cell voltage value and cell current value of the cell at the current sampling time; For each sub-sampling time between the current sampling time and the previous sampling time adjacent to the current sampling time, collecting the cell current value of the cell at the sub-sampling time; Calculate the cell current value at the current sampling moment and the average value of each cell current value collected at each sub-sampling moment between the current sampling moment and the previous sampling moment, and use the average value as the final cell current value of the cell at the current sampling moment.

3. The method according to claim 1 or 2, characterized in that: The preset time interval between two adjacent sampling moments, the calculation of the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment according to the battery cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the battery cell current value at the current sampling moment, includes: For each sampling moment between the target historical sampling moment and the current sampling moment, calculate the product of the cell current value collected at the sampling moment and the preset time length, and calculate the product of the cell current value at the current sampling moment and the preset time length; Calculate the product corresponding to each sampling moment between the target historical sampling moment and the current sampling moment, and the sum of the products corresponding to the current sampling moment, to obtain the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment.

4. The method according to claim 1, characterized in that: Each of the other cells is respectively connected to a balancing resistor, and the method further comprises: For each of the other cells, the target balancing time of the other cells is calculated by the following formula: Among them, I bal Characterizes the balancing current value of the other cells; R bal Characterizes the resistance value of the balancing resistor corresponding to the other battery cell; the balancing resistor is used to convert the electrical energy in the other battery cell into heat energy to consume the power of the other battery cell; V bal Characterizes the cell plateau voltage value of the other cell, V bal The value range is 3200mv-3300mv; Among them, T bal Characterizes the target balancing time of the other battery cell; DiffCapx characterizes the difference in charge between the other battery cell and the reference battery cell; Ratio is a constant greater than 0 and less than 1.

5. The method according to claim 4, characterized in that: The method further comprises: For each of the other cells, in the process of performing cell balancing on the other cells through the balancing resistor corresponding to the other cells, detecting in real time the balanced cell voltage value of the other cells during cell balancing; If the current balancing time of the other battery cells does not reach the target balancing time of the other battery cells, and the current balancing battery cell voltage value of the other battery cells is equal to the first battery cell voltage value, then the battery cell balancing of the other battery cells is stopped; the first battery cell voltage value is the difference between the minimum battery cell voltage value and the preset voltage value; If the current balancing time of the other battery cell reaches the target balancing time of the other battery cell, and the current balancing battery cell voltage value of the other battery cell is greater than the first battery cell voltage value, then the battery cell balancing of the other battery cell is stopped.

6. A cell balancing processing device, characterized in that: include: The acquisition module is used to collect the cell voltage value and the cell current value of each cell in the target battery at the current sampling time during the charging process of the target battery; A first determination module is used to determine a minimum cell voltage value from the cell voltage values ​​of the cells collected at the current sampling moment if it is detected that the target battery is in a floating charge state at the current sampling moment, so as to use the cell corresponding to the minimum cell voltage value as a reference cell; A search module, for searching, for the nth other battery cell except the reference battery cell, a candidate battery cell voltage value that is less than or equal to the minimum battery cell voltage value from the battery cell voltage values ​​collected by the nth other battery cell at each historical sampling moment; the historical sampling moment is a sampling moment before the current sampling moment among the sampling moments in this charging process; when the total number of other battery cells is 1, n is 1; when the total number of other battery cells is greater than or equal to 2, n is a positive integer from 1 to N in sequence, and N is the total number of other battery cells; A second determination module is used to determine a target historical sampling time closest to the current sampling time for the nth other battery cell according to the historical sampling time corresponding to the candidate battery cell voltage value of the nth other battery cell; The first calculation module is used to calculate the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment based on the battery cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the battery cell current value at the current sampling moment, so as to use the charging capacity as the charge difference between the nth other battery cell and the reference battery cell.

7. The device according to claim 6, characterized in that: There are a preset number of sub-sampling moments between two adjacent sampling moments; when the acquisition module is used to collect the cell voltage value and the cell current value of the cell at the current sampling moment, it is specifically used to: Collect the cell voltage value and cell current value of the cell at the current sampling time; For each sub-sampling time between the current sampling time and the previous sampling time adjacent to the current sampling time, collecting the current cell current value of the cell at the sub-sampling time; Calculate the cell current value at the current sampling moment and the average value of each cell current value collected at each sub-sampling moment between the current sampling moment and the previous sampling moment, and use the average value as the final cell current value of the cell at the current sampling moment.

8. The device according to claim 6 or 7, characterized in that: The interval between two adjacent sampling moments is a preset time length, and the first calculation module is used to calculate the charging power of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment according to the battery cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the battery cell current value at the current sampling moment, specifically for: For each sampling moment between the target historical sampling moment and the current sampling moment, calculate the product of the cell current value collected at the sampling moment and the preset time length, and calculate the product of the cell current value at the current sampling moment and the preset time length; Calculate the product corresponding to each sampling moment between the target historical sampling moment and the current sampling moment, and the sum of the products corresponding to the current sampling moment, to obtain the charging capacity of the nth other battery cell in the time period between the target historical sampling moment and the current sampling moment.

9. An electronic device, characterized in that: include: A processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate via the bus, and when the machine-readable instructions are executed by the processor, the steps of the method as claimed in any one of claims 1 to 5 are performed.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are executed.

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