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

Abstract

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

Description

TECHNICAL FIELD

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

[0002] A battery (for example, a lithium iron phosphate battery) generally includes a plurality of single battery cells, and each battery cell has a capacity difference in the production process. For example, the production standard is to produce a battery cell with a capacity of 10000mA, but the actual manufactured battery cell may have a capacity of 10003mA or 99996mA. During use, due to the difference in self-discharge rates of different battery cells in the battery, the capacities (remaining capacities) of the battery cells are different after use for a period of time.

[0003] In this case, if the battery is charged, the battery cell with the largest capacity will generally be charged first, and if the battery continues to be charged, the battery cell will be damaged due to overcharging. Therefore, at this time, the charging of the battery needs to be stopped, but other battery cells with smaller capacities in the battery may not be fully charged.

[0004] If the battery is discharged, the battery cell with the smallest capacity will generally be discharged first, and if the battery continues to be discharged, the battery cell will be damaged due to over-discharge. Therefore, at this time, the discharging of the battery needs to be stopped, but other battery cells with larger capacities in the battery may not be fully discharged.

[0005] Therefore, it is necessary to balance the battery cells in the battery to ensure that the capacities of the single battery cells in the battery are consistent, so as to ensure that each battery cell remains in the same state during normal use, thereby avoiding overcharging and over-discharging.

[0006] Before balancing the battery cells in the battery, it is necessary to determine the difference between the capacities of the battery cells in the battery. Therefore, there is an urgent need in the prior art for a method for determining the difference between the capacities of the battery cells in the battery. SUMMARY

[0007] Therefore, the purpose of the present application is to provide a processing method and device for battery cell balancing, electronic equipment and a readable storage medium to improve the accuracy of determining the difference between the capacities of the battery cells in the battery.

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

[0009] During charging 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 that the target battery is in the floating state at the current sampling moment, a minimum cell voltage value is determined from the cell voltage values of each of the cells collected at the current sampling moment, and a cell corresponding to the minimum cell voltage value is taken as a reference cell;

[0011] 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 for the nth other cell from the cell voltage values of the nth other cell collected at each historical sampling moment; the historical sampling moment is a sampling moment before the current sampling moment in each of the sampling moments in the current 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 a positive integer from 1 to N in turn, and N is the total number of other cells;

[0012] A target historical sampling moment closest to the current sampling moment is determined for the nth other cell according to the historical sampling moment corresponding to the candidate cell voltage value of the nth other cell;

[0013] A charging electric quantity of the nth other cell in a time period between the target historical sampling moment and the current sampling moment is calculated according to the cell current values collected from each sampling moment between the target historical sampling moment and the current sampling moment and the cell current value of the current sampling moment, and the charging electric quantity is taken as an electric quantity difference between the nth other cell and the reference cell.

[0014] With reference to the first aspect, a first possible implementation of the first aspect is provided in the embodiments of the present application, wherein there are a preset number of sub-sampling moments between two adjacent sampling moments; the cell voltage value and the cell current value of the cell at the current sampling moment are collected, including:

[0015] The current cell voltage value and the cell current value of the cell at the current sampling moment are collected;

[0016] For each of the sub-sampling moments between the current sampling moment and the previous sampling moment adjacent to the current sampling moment, the current cell current value of the cell at the sub-sampling moment is collected;

[0017] An average value of the cell current value of the current sampling moment and the cell current values collected at each of the sub-sampling moments between the current sampling moment and the previous sampling moment is calculated, and the average value is taken as the final cell current value of the cell at the current sampling moment.

[0018] With reference to the first aspect or the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, the two adjacent sampling time points are separated by a preset time length, and the calculation of the charging capacity of the nth other battery cell in the time period between the target historical sampling time point and the current sampling time point comprises:

[0019] calculating the product of the battery current value collected at each sampling time point between the target historical sampling time point and the current sampling time point and the preset time length, and the product of the battery current value at the current sampling time point and the preset time length;

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

[0021] With reference to the first aspect, in a third possible implementation manner of the first aspect, each of the other battery cells is connected to an equalization resistor, and the method further comprises:

[0022] for each of the other battery cells, calculating a target equalization time of the other battery cell by the following formula:

[0023]

[0024] wherein, I bal represents the equalization current value of the other battery cell; R bal represents the resistance value of the equalization resistor corresponding to the other battery cell; the equalization resistor is used to convert the electric energy in the other battery cell into heat energy to consume the electric quantity of the other battery cell; V bal represents the battery platform period voltage value of the other battery cell, and V bal has a value range of 3200mv-3300mv.

[0025]

[0026] wherein, T bal represents the target equalization time of the other battery cell; DiffCapx represents the electric quantity difference between the other battery cell and the reference battery cell; and Ratio is a constant greater than 0 and less than 1.

[0027] With reference to the third possible implementation manner of the first aspect, the application provides a fourth possible implementation manner of the first aspect.

[0028] In the process of balancing the other battery cell through the balancing resistor corresponding to the other battery cell, the balancing battery voltage value of the other battery cell is detected in real time when the other battery cell is balanced;

[0029] If the current balancing time of the other battery cell does not reach the target balancing time of the other battery cell, and the balancing battery voltage value of the other battery cell at present is equal to the first battery voltage value, the balancing of the other battery cell is stopped; the first battery voltage value is the difference between the minimum battery voltage value and a 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 balancing battery voltage value of the other battery cell at present is greater than the first battery voltage value, the balancing of the other battery cell is stopped.

[0031] In the second aspect, the application further provides a processing device for battery cell balancing, comprising:

[0032] The acquisition module is configured to, during the target battery charging process, acquire, 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 moment;

[0033] The first determination module is configured to, if it is detected that the target battery is in a floating state at the current sampling moment, determine a minimum battery voltage value from the battery cell voltage values of all the battery cells acquired at the current sampling moment, and take the battery cell corresponding to the minimum battery voltage value as a reference battery cell;

[0034] The search module is configured to, for an nth other battery cell except the reference battery cell, search for a candidate battery voltage value less than or equal to the minimum battery voltage value for the nth other battery cell from the battery cell voltage values of the nth other battery cell acquired at historical sampling moments; the historical sampling moments are sampling moments before the current sampling moment in all the sampling moments in the present 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 sequentially a positive integer from 1 to N, and N is the total number of other battery cells;

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

[0036] The first calculation module is configured to calculate, according to the battery cell current values collected at each sampling time between the target historical sampling time and the current sampling time and the battery cell current value at the current sampling time, a charging electric quantity of the nth other battery cell in a time period between the target historical sampling time and the current sampling time, and take the charging electric quantity as an electric quantity difference between the nth other battery cell and the reference battery cell.

[0037] With reference to the second aspect, a first possible implementation manner of the second aspect is provided in the embodiments of the present application, wherein a preset number of sub-sampling times exist between two adjacent sampling times; and the collection module, when used for collecting the battery cell voltage value and the battery cell current value of the battery cell at the current sampling time, is specifically used for:

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

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

[0040] calculating an average value of the battery cell current value at the current sampling time and the battery cell current values collected at each of the sub-sampling times between the current sampling time and the previous sampling time, and taking the average value as the final battery cell current value of the battery cell at the current sampling time.

[0041] With reference to the second aspect or the first possible implementation manner of the second aspect, a second possible implementation manner of the second aspect is provided in the embodiments of the present application, wherein a preset time length exists between two adjacent sampling times, and the first calculation module, when used for calculating, according to the battery cell current values collected at each sampling time between the target historical sampling time and the current sampling time and the battery cell current value at the current sampling time, a charging electric quantity of the nth other battery cell in a time period between the target historical sampling time and the current sampling time, is specifically used for:

[0042] calculating, for each of the sampling times between the target historical sampling time and the current sampling time, a product of the battery cell current value collected at the sampling time and the preset time length, and a product of the battery cell current value at the current sampling time and the preset time length;

[0043] calculating a sum value of the products corresponding to each of the sampling times between the target historical sampling time and the current sampling time and the product corresponding to the current sampling time, to obtain the charging electric quantity of the nth other battery cell in a time period between the target historical sampling time and the current sampling time.

[0044] With reference to the second aspect, the embodiments of the present application provide a third possible implementation manner of the second aspect, wherein each of the other battery cells is connected with an equalization resistor, and the device further comprises:

[0045] a second calculation module, configured to calculate, for each of the other battery cells, a target equalization time of the other battery cell according to the following formula:

[0046]

[0047] wherein I bal represents an equalization current value of the other battery cell; R bal represents a resistance value of an equalization resistor corresponding to the other battery cell, the equalization resistor being used to convert electrical energy in the other battery cell into heat energy so as to consume the electrical energy in the other battery cell; V bal represents a battery cell platform period voltage value of the other battery cell, V bal has a value range of 3200mv-3300mv;

[0048]

[0049] wherein T bal represents a target equalization time of the other battery cell; DiffCapx represents a difference in electrical energy between the other battery cell and the reference battery cell; and Ratio is a constant greater than 0 and less than 1.

[0050] With reference to the third possible implementation manner of the second aspect, the embodiments of the present application provide a fourth possible implementation manner of the second aspect, wherein the device further comprises:

[0051] a detection module, configured to, for each of the other battery cells, detect, in real time, an equalization battery cell voltage value of the other battery cell during equalization of the other battery cell by the equalization resistor corresponding to the other battery cell;

[0052] a first stopping module, configured to, if the current equalization time of the other battery cell does not reach the target equalization time of the other battery cell, and the equalization battery cell voltage value of the other battery cell is equal to a first battery cell voltage value, stop equalization of the other battery cell, the first battery cell voltage value being a difference between the minimum battery cell voltage value and a preset voltage value;

[0053] a second stopping module, configured to, if the current equalization time of the other battery cell reaches the target equalization time of the other battery cell, and the equalization battery cell voltage value of the other battery cell is greater than the first battery cell voltage value, stop equalization of the other battery cell.

[0054] In a third aspect, the embodiments of the present application further provide an electronic device, comprising a processor, a memory and a bus, the memory stores machine readable instructions executable by the processor, when the electronic device is running, the processor communicates with the memory through the bus, and the machine readable instructions are executed by the processor to perform the steps in any possible implementation manner of the first aspect.

[0055] In a fourth aspect, the embodiments of the present application further provide a computer readable storage medium, the computer readable storage medium stores a computer program, and the computer program is executed by a processor to perform the steps in any possible implementation manner of the first aspect.

[0056] The embodiments of the present application provide a processing method and device for cell balancing, an electronic device and a readable storage medium. In the processing method, during a charging process of a target battery, for each cell in the target battery, a cell voltage value and a cell current value of the cell at a current sampling moment are collected; if it is detected that the target battery is in a floating state at the current sampling moment, a minimum cell voltage value is determined from the cell voltage values of all the cells collected at the current sampling moment, and a cell corresponding to the minimum cell voltage value is taken as a reference cell; for an nth other cell except the reference cell, a candidate cell voltage value less than or equal to the minimum cell voltage value is found for the nth other cell from the cell voltage values of the nth other cell collected at historical sampling moments; the historical sampling moments are sampling moments before the current sampling moment in the charging process; when the total number of the other cells is 1, n is 1; when the total number of the other cells is greater than or equal to 2, n takes a positive integer from 1 to N in turn, and N is the total number of the other cells; and a target historical sampling moment closest to the current sampling moment is determined for the nth other cell according to the historical sampling moment corresponding to the candidate cell voltage value of the nth other cell. At this time, the target historical sampling moment of the nth other cell determined represents that the electric quantity of the nth other cell at the target historical sampling moment is close to the electric quantity of the reference cell at the current sampling moment. That is, the electric quantity of the nth other cell charged in a time period from the target historical sampling moment to the current sampling moment is more than the electric quantity of the reference cell at the current sampling moment, and therefore, the charging electric quantity of the nth other cell in the time period between the target historical sampling moment and the current sampling moment is calculated according to the cell current values collected at each sampling moment between the target historical sampling moment and the current sampling moment and the cell current value at the current sampling moment, so as to take the charging electric quantity as the electric quantity difference between the nth other cell and the reference cell. In this way, the electric quantity difference between the electric quantities of all the cells in the target battery is more accurate.

[0057] In order to make the above objectives, characteristics and advantages of the present application more apparent, clear and easy to understand, the following will specifically describe a preferred embodiment in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0058] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments, and it should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation to the scope, and for those skilled in the art, other related drawings can also be obtained without paying creative labor on the basis of these drawings.

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

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

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

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

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

[0064] In order to make the objectives, technical solutions and advantages of the embodiments of the present application more apparent, the following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein 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 claimed present application, but only represents 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 paying creative labor are within the scope of protection of the present application.

[0065] In the prior art, the difference in electric quantity between the battery cells is generally determined by the pressure difference between the battery cells. However, the platform period of the battery cells in a battery (for example, a lithium iron phosphate battery) is relatively long, and the voltage difference between the battery cells is very small during the platform period, so it is difficult to determine the difference in electric quantity between the battery cells by the pressure difference. When the difference in electric quantity between the battery cells is determined by using an open circuit voltage (OCV) table of the battery, the battery needs to be static for several hours, which wastes time. Moreover, as the battery (for example, 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 difference in electric quantity becomes larger and larger.

[0066] In view of the above problems, based on this, the embodiment of the present application provides a kind of processing method, device, electronic equipment and readable storage medium for battery equalization, which are described below by embodiment.

[0067] To facilitate the understanding of the present embodiment, first of all, a kind of processing method for battery equalization disclosed in the embodiment of the present application is introduced in detail. Figure 1 The flow chart of the processing method for battery equalization provided by the embodiment of the present application is shown as Figure 1 As shown in the figure, the following steps S101-S105 are included:

[0068] S101: In the process of charging 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.

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

[0070] Exemplarily, the battery cell A and the battery cell B in the target battery are taken as examples for illustration, Figure 2 The schematic diagram of the correspondence between each sampling time, the battery cell voltage value and the battery cell current value provided by the embodiment of the present application is shown as Figure 2 As shown in the figure, t1-t6 are each sampling time, t6 is the current sampling time, t1-t5 are historical sampling times, Va6 is the battery cell voltage value of the battery cell A at the current sampling time t6, Ia6 is the battery cell current value of the battery cell A at the current sampling time t6, Vb6 is the battery cell voltage value of the battery cell B at the current sampling time t6, and Ib6 is the battery cell current value of the battery cell B at the current sampling time t6.

[0071] In a possible implementation, there are a preset number of sub-sampling times between two adjacent sampling times. When collecting the battery cell voltage value and the battery cell current value of the battery cell at the current sampling time in step S101, the following steps can be performed:

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

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

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

[0075] Figure 3 A schematic diagram of the sub-sampling moment between two adjacent sampling moments is shown as provided by the embodiments of the present application, as shown in Figure 3 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, which are sub-sampling moments t5.1, t5.2, t5.3 and t5.4.

[0076] When step S1012 is performed, for example, the current sampling moment is t6, the previous sampling moment adjacent to the current sampling moment is t5, and the sub-sampling moments between the current sampling moment t6 and the previous sampling moment t5 are t5.1, t5.2, t5.3 and t5.4. The battery cell current values of the battery cell A at the sub-sampling moments are collected, which are Ia5.1, Ia5.2, Ia5.3 and Ia5.4. The battery cell current values of the battery cell B at the sub-sampling moments are collected, which are Ib5.1, Ib5.2, Ib5.3 and Ib5.4.

[0077] When step S1013 is performed, for example, for the battery cell A, the average value of the battery cell current value Ia6 at the current sampling moment t6 and the battery cell current values Ia5.1, Ia5.2, Ia5.3 and Ia5.4 at the sub-sampling moments is calculated, and the average value is taken as the final battery cell current value of the battery cell A at the current sampling moment t6.

[0078] S102: If the target battery is detected in the floating state at the current sampling moment, the minimum battery cell voltage value is determined from the battery cell voltage values of each battery cell collected at the current sampling moment, and the battery cell corresponding to the minimum battery cell voltage value is taken as the reference battery cell.

[0079] In this embodiment, when the target battery has been in the charging state for a certain time length recently and the target battery is in the floating charging state at the current sampling moment, the power difference calculation is triggered. The floating charging state refers to a state in which the target battery is about to be fully charged but continues to be charged at a small current value. The state of being about to be fully charged can be that the SOC of the target battery reaches a preset percentage, and 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, Va6 is less than Vb6, and Va6 is the minimum cell voltage value. The cell A corresponding to Va6 is taken as the reference cell.

[0081] S103: For the nth other cell except the reference cell, the candidate cell voltage value less than or equal to the minimum cell voltage value is found for the nth other cell from the cell voltage values collected at each historical sampling moment of the nth other cell. The historical sampling moment is a sampling moment located before the current sampling moment in each sampling moment in the current 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 a positive integer from 1 to N, and N is the total number of other cells.

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

[0083] For the nth other cell B, the 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 at each historical sampling moment (t1-t5) of the nth other cell B. For example, if the cell voltage values Vb1<Vb2<Vb3≤Va6<Vb4<Vb5<Vb6, Vb1, Vb2, and Vb3 are the candidate cell voltage values of the nth other cell B.

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

[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 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. The historical sampling time t3 is the closest to the current sampling time t6, and thus the historical sampling time t3 is the target historical sampling time of the nth other cell B.

[0087] S105: According to the cell current values collected at each sampling time between the target historical sampling time and the current sampling time, and the cell current value at the current sampling time, the charging electric quantity of the nth other cell in the time period between the target historical sampling time and the current sampling time is calculated, so as to take the charging electric quantity as the electric quantity difference between the nth other cell and the reference cell.

[0088] In this embodiment, the nth other cell is taken as the cell B. Since the cell voltage value Vb3 of the cell B at the target historical sampling time t3 is close to the cell voltage value Va6 of the reference cell A at the current sampling time t6, it is considered that the electric quantity of the cell B at the target historical sampling time t3 is close to the electric quantity of the reference cell A at the current sampling time t6 during the charging process. Then, the electric quantity charged to the cell B in the time period between the target historical sampling time t3 and the current sampling time t6 is equivalent to the electric quantity of the cell B more than that of the cell A at the current sampling time t6.

[0089] In this embodiment, the charging electric quantity of the cell B in the time period between the target historical sampling time t3 and the current sampling time t6 can be calculated according to the cell current values (Ib4, Ib5, Ib6) collected at each sampling time (t4, t5) between the target historical sampling time t3 and the current sampling time t6, and at the current sampling time t6, so as to take the charging electric quantity as the electric quantity difference between the cell B and the reference cell A. That is, the electric quantity difference between the other cell and the reference cell refers to the electric quantity of the other cell more than that of the reference cell.

[0090] In a possible implementation, the interval between two adjacent sampling times is a preset time length. When step S105 is performed, the following steps can be specifically performed:

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

[0092] S1052: Calculate the sum of the product corresponding to each sampling time from the target historical sampling time to the current sampling time, and the product corresponding to the current sampling time, to obtain the charging electric quantity of the nth other electric core in the time period between the target historical sampling time and the current sampling time.

[0093] As shown in the example, Figure 2 The sampling time t1-t2 is separated by a preset time T, and the sampling time t2-t3, t3-t4, t4-t5, t5-t6 is also separated by a preset time T.

[0094] In step S1051, taking the nth other electric core as an example, the product Ib4' of the electric core current value Ib4 collected at sampling time t4 and the preset time T, and the product Ib5' of the electric core current value Ib5 collected at sampling time t5 and the preset time T are calculated for each sampling time (t4, t5) between the target historical sampling time t3 and the current sampling time t6. And calculate the product Ib6' of the electric core current value Ib6 of the current sampling time t6 and the preset time T.

[0095] In step S1052, the sum of the products Ib4', Ib5', Ib6' corresponding to the sampling times t4, t5, t6 is calculated, that is, the sum = Ib4' + Ib5' + Ib6'. The sum is taken as the charging electric quantity of the electric core B in the time period between the target historical sampling time t3 and the current sampling time t6. The calculated charging electric quantity is taken as the electric quantity of the electric core B more than the reference electric core A at the current sampling time t6, that is, the electric quantity difference between the electric core B and the reference electric core A.

[0096] In one possible implementation, after determining the electric quantity difference between the other electric core and the reference electric core, the electric core balancing of the other electric core is needed, that is, the electric quantity in the other electric core needs to be reduced. In this embodiment, the electric core balancing of the other electric core can be realized by consuming the electric quantity in the other electric core (such as discharging), so as to reduce the difference between the electric quantity of the other electric core and the electric quantity of the reference electric core.

[0097] When the electric core balancing of the other electric core is performed, the balancing time of the other electric core needs to be determined first, that is, the discharging time of the other electric core needs to be determined first. In this embodiment, each other electric core is connected with an equalization resistor, and for each other electric core, the target balancing time of the other electric core is calculated by the following formula:

[0098]

[0099] Wherein, I bal represents the balancing current value of the other electric core; R bala resistance value of an equalization resistor corresponding to the other battery cell; the equalization resistor is used to convert electrical energy in the other battery cell into heat energy to consume the electrical energy in the other battery cell; V bal a battery cell platform period voltage value of the other battery cell, V bal the value range of the battery cell platform period voltage value is 3200mv-3300mv;

[0100]

[0101] wherein, T bal a target equalization time of the other battery cell; DiffCapx represents the difference in electrical energy between the other battery cell and the reference battery cell; Ratio is a constant greater than 0 and less than 1.

[0102] In this embodiment, when the other battery cell is subjected to battery cell equalization (e.g., discharging), the other battery cell is used to provide electrical energy for an equalization resistor connected to the other battery cell, and the equalization resistor is used to convert the electrical energy into heat energy to consume the electrical energy in the other battery cell.

[0103] In a possible implementation, in the process of using the equalization resistor to equalize the other battery cell, since the collected battery cell voltage value may not be accurate when collecting the battery cell current value or the battery cell voltage value, the calculated equalization time may not be accurate, and thus there may be a case where the electrical energy in the other battery cell is close to that in the reference battery cell before the equalization time is reached. At this time, if the equalization of the other battery cell continues, the electrical energy in the other battery cell will be less than that in the reference battery cell, and the difference will become larger and larger.

[0104] In view of the above problem, in this embodiment, the following steps S1061-S1063 can also be performed:

[0105] S1061: For each other battery cell, in the process of equalizing the other battery cell through the equalization resistor corresponding to the other battery cell, the equalization battery cell voltage value of the other battery cell during battery cell equalization is detected in real time.

[0106] S1062: If the current equalization time of the other battery cell has not reached the target equalization time of the other battery cell, and the current equalization battery cell voltage value of the other battery cell is equal to the first battery cell voltage value, stop equalizing the other battery cell; the first battery cell voltage value is the difference between the minimum battery cell voltage value and a preset voltage value.

[0107] In this embodiment, if the current equalization battery cell voltage value of the other battery cell drops to the first battery cell voltage value, it means that the electrical energy in the other battery cell is not much different from that in the reference battery 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 3 mV and the minimum cell voltage value Va6 is 2000 mV, the first cell voltage value is 1997 mV.

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

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

[0111] Based on the same technical concept, the application also provides a processing device for cell equalization, Figure 4 The structure schematic diagram of the processing device for cell equalization provided by the embodiment of the application is shown in FIG. 1. Figure 4 As shown in FIG. 1, the device comprises:

[0112] The acquisition module 401 is configured to, during the target battery charging process, acquire, for each cell in the target battery, a cell voltage value and a cell current value of the cell at a current sampling moment;

[0113] The first determination module 402 is configured to, if the target battery is detected to be in a floating state at the current sampling moment, determine a minimum cell voltage value from the cell voltage values of each cell acquired at the current sampling moment, and take the cell corresponding to the minimum cell voltage value as a reference cell;

[0114] The search module 403 is configured to, for an nth other cell except the reference cell, search for a candidate cell voltage value less than or equal to the minimum cell voltage value for the nth other cell from the cell voltage values of the nth other cell acquired at each historical sampling moment; the historical sampling moment is a sampling moment before the current sampling moment in each sampling moment in the current 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 a positive integer from 1 to N in turn, and N is the total number of other cells.

[0115] The second determination module 404 is configured to determine a target historical sampling moment closest to the current sampling moment for the nth other cell according to the historical sampling moment corresponding to the candidate cell voltage value of the nth other cell.

[0116] The first calculation module 405 is configured to calculate the charging electric quantity of the nth other electric core in a time period between the target historical sampling time and the current sampling time according to the electric core current value collected at each sampling time between the target historical sampling time and the current sampling time and the electric core current value of the current sampling time, and take the charging electric quantity as the electric quantity difference between the nth other electric core and the reference electric core.

[0117] Optionally, there are a preset number of sub-sampling times between two adjacent sampling times; when collecting the electric core voltage value and the electric core current value of the electric core at the current sampling time, the collection module 401 is specifically configured to:

[0118] collect the electric core voltage value and the electric core current value of the electric core at the current sampling time;

[0119] collect the electric core current value of the electric core at each sub-sampling time between the current sampling time and the previous sampling time adjacent to the current sampling time;

[0120] calculate the average value of the electric core current value of the current sampling time and the electric core current value collected at each sub-sampling time between the current sampling time and the previous sampling time, and take the average value as the final electric core current value of the electric core at the current sampling time.

[0121] Optionally, two adjacent sampling times are separated by a preset time length, and the first calculation module 405, when calculating the charging electric quantity of the nth other electric core in a time period between the target historical sampling time and the current sampling time according to the electric core current value collected at each sampling time between the target historical sampling time and the current sampling time and the electric core current value of the current sampling time, is specifically configured to:

[0122] for each sampling time between the target historical sampling time and the current sampling time, calculate the product of the electric core current value collected at the sampling time and the preset time length, and calculate the product of the electric core current value of the current sampling time and the preset time length;

[0123] calculate the sum of the product corresponding to each sampling time between the target historical sampling time and the current sampling time and the product corresponding to the current sampling time, to obtain the charging electric quantity of the nth other electric core in a time period between the target historical sampling time and the current sampling time.

[0124] Optionally, each other electric core is connected with an equalization resistor, and the device further comprises:

[0125] a second calculation module, configured to calculate, for each of the other battery cells, a target equalization time of the other battery cell by the following formula:

[0126]

[0127] wherein I bal represents an equalization current value of the other battery cell; R bal represents a resistance value of an equalization resistance corresponding to the other battery cell; the equalization resistance is used to convert electrical energy in the other battery cell into heat energy to consume the electrical quantity of the other battery cell; V bal represents a battery cell platform period voltage value of the other battery cell, V bal the value range of V

[0128]

[0129] wherein T bal represents the target equalization time of the other battery cell; DiffCapx represents the electrical quantity difference 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, for each of the other battery cells, detect an equalization battery cell voltage value of the other battery cell in real time in the process of battery cell equalization of the other battery cell through the equalization resistance corresponding to the other battery cell;

[0132] a first stop module, configured to, if the current equalization time of the other battery cell does not reach the target equalization time of the other battery cell, and the equalization battery cell voltage value of the other battery cell at present is equal to a first battery cell voltage value, stop the battery cell equalization of the other battery cell; the first battery cell voltage value is a difference value between the minimum battery cell voltage value and a preset voltage value;

[0133] a second stop module, configured to, if the current equalization time of the other battery cell reaches the target equalization time of the other battery cell, and the equalization battery cell voltage value of the other battery cell at present is greater than the first battery cell voltage value, stop the battery cell equalization of the other battery cell.

[0134] Figure 5 A structural schematic diagram of an electronic device provided by the embodiment of the present application, comprising: a processor 501, a memory 502 and a bus 503, the memory 502 stores machine readable instructions executable by the processor 501, when the electronic device runs the above information processing method, the processor 501 and the memory 502 communicate through the bus 503, the processor 501 executes the machine readable instructions to execute the method steps described in embodiment one.

[0135] The embodiment of the present application further provides a computer readable storage medium, and the computer readable storage medium stores a computer program. The computer program is run by a processor to execute the method steps in the embodiment one.

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

[0137] In several embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented by other manners. The apparatus embodiments described above are only schematic, for example, the division of the modules is only a logical function division, and actual implementation can have another division manner, for example, a plurality of modules or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some communication interfaces, apparatuses or units, and can be electrical, mechanical or other forms.

[0138] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, that is, can be located in one place, or can be distributed on a plurality of network units. According to actual needs, part or all of the units can be selected to achieve the purpose of the embodiment scheme.

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

[0140] If the functions are realized in the form of software function units and sold or used as independent products, they can be stored in a nonvolatile computer readable storage medium executable by a processor. Based on this understanding, the technical solutions of the present application essentially or the parts of the prior art that make contributions or parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (Read-Only Memory, ROM), a random access memory (Random Access Memory, RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0141] Finally, it should be noted that: the above-described embodiments are only specific embodiments of the present application, which are used to illustrate the technical solutions of the present application, but not to limit them. The protection scope of the present application is not limited thereto. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily think of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed by the present application, or make equivalent replacements to some of the technical features. The modifications, changes or replacements do not make the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to 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 moment that the target battery is in a floating charge state, determining a minimum cell voltage value from the cell voltage values ​​of the cells collected at the current sampling moment, and using the cell corresponding to the minimum cell voltage value as a reference cell; For an nth other battery cell other than the reference battery cell, find a candidate battery cell voltage value that is less than or equal to the minimum battery cell voltage value for the nth other battery cell from the battery cell voltage values ​​collected at each historical sampling moment for the nth other battery cell; the historical sampling moment is a sampling moment that is 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, where 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 based on the historical sampling time corresponding to the voltage value of the candidate battery cell of the nth other battery cell; Based on the cell current value collected at each sampling moment between the target historical sampling moment and the current sampling moment, and the cell current value at the current sampling moment, calculate the charging capacity of the nth other 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 capacity difference between the nth other cell and the reference 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; collecting the cell voltage value and the cell current value of the cell at the current sampling moment includes: Collect the cell voltage and current values ​​of the cell at the current sampling moment; For each sub-sampling moment between the current sampling moment and the previous sampling moment adjacent to the current sampling moment, collecting the cell current value of the cell at the sub-sampling moment; 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 interval between two adjacent sampling moments is a preset time length, 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 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 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 battery cells is respectively connected to a balancing resistor, and the method further includes: For each of the other cells, the target balancing time of the other cells is calculated using 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 The target balancing time of the other battery cell is represented; DiffCapx represents 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 cell through the balancing resistor corresponding to the other cell, detecting in real time the balanced cell voltage value of the other cell during cell balancing; If the current balancing time of the other battery cell does not reach the target balancing time of the other battery cell, and the current balancing cell voltage value of the other battery cell is equal to the first cell voltage value, then stop cell balancing for the other battery cell; the first cell voltage value is the difference between the minimum 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 cell voltage value of the other battery cell is greater than the first cell voltage value, 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 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 determining module, configured to, if it is detected at a current sampling moment that the target battery is in a floating charge state, determine a minimum cell voltage value from the cell voltage values ​​of the cells collected at the current sampling moment, and use the cell corresponding to the minimum cell voltage value as a reference cell; a search module, configured to search, for an nth other battery cell other than the reference battery cell, for 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 being 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, where N is the total number of other battery cells; A second determining module is configured to determine, for the nth other battery cell, a target historical sampling time closest to the current sampling time based on the historical sampling time corresponding to the voltage value of the candidate battery cell 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 capacity 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 and current values ​​of the cell at the current sampling moment; For each sub-sampling moment between the current sampling moment and the previous sampling moment adjacent to the current sampling moment, collecting the current cell current value of the cell at the sub-sampling moment; 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 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, 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 according to 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, which, when executed by a processor, executes the steps of the method according to any one of claims 1 to 5.

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