Method and device for calculating state of charge of battery, vehicle and storage medium

Abstract

The application discloses a battery state of charge calculation method and device, a vehicle and a storage medium. The method is applied to a battery pack, and the battery pack comprises a battery cell. The method comprises the following steps: acquiring charge information of the battery cell, wherein the charge information comprises a first state of charge and a second state of charge of the battery cell; determining whether the charge information satisfies a specified accuracy determination condition; if the charge information satisfies the specified accuracy determination condition, determining a target state of charge of the battery cell based on the second state of charge; and if the charge information does not satisfy the specified accuracy determination condition, determining the target state of charge of the battery cell based on the first state of charge. Since the accuracy of the total state of charge of the battery pack calculated based on the second state of charge is higher than the accuracy of the total state of charge of the battery pack calculated based on the first state of charge when the charge information satisfies the specified accuracy determination condition, the estimation of the total state of charge of the battery pack by the vehicle can be more accurate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power batteries, and more particularly to a battery state of charge calculation method and device, a vehicle, and a storage medium. BACKGROUND

[0002] The development of a battery management system (BMS) plays a key role in improving the safety and performance of electric vehicles and is currently the core technology of electric vehicle research and development. Among them, the estimation of the state of charge (SOC) of the battery pack is one of the difficulties in the development of the BMS.

[0003] In related technologies, the SOC estimation usually adopts an ampere-hour integration method combined with an open circuit voltage method. The ampere-hour integration method directly uses the current for integral calculation from the definition of electric quantity and is a basic method for SOC calculation. Its disadvantage is that the algorithm accuracy is highly dependent on the accuracy of the initial SOC and the sensor accuracy. Once an error occurs, the error will be accumulated over time and cannot be eliminated. To this end, the open circuit voltage method is added to correct the results of the ampere-hour integration calculation. The principle is to use the linear relationship between the open circuit voltage (OCV) and the SOC, obtain the SOC value through table lookup after collecting the battery voltage after sufficient standing, as a correction value, which can improve the SOC estimation accuracy to a certain extent.

[0004] However, unlike ternary batteries, in the OCV curve of the lithium iron phosphate battery, in the regions of 30% to 55% and 65% to 99% of the SOC (i.e., the platform region), the OCV changes very little with the SOC and the OCV change range cannot be measured by the existing voltage sampling device, so the open circuit voltage method can only be used to correct the SOC in the limited non-platform region. However, the lithium iron phosphate battery also has a significant voltage hysteresis characteristic and a slow depolarization speed phenomenon, so the battery is affected by the pre-charging and discharging conditions, and the maximum possible error of the measured OCV value is more than 20mV, which leads to a large error in the SOC correction value obtained by table lookup in the case of a large error in the OCV, and further causes the SOC to be corrected incorrectly, so that the calculated battery pack SOC is not accurate. SUMMARY

[0005] The present application provides a battery state of charge calculation method and device, a vehicle, and a storage medium.

[0006] In a first aspect, some embodiments of the present application provide a method for calculating a state of charge of a battery. The method is applied to a battery pack, and the battery pack includes a battery cell. The method includes: obtaining charge information of the battery cell, the charge information including a first state of charge and a second state of charge of the battery cell, the first state of charge being determined based on a preset integral algorithm, and the second state of charge being determined based on a preset filtering algorithm; determining whether the charge information satisfies a specified accuracy determination condition, the specified accuracy determination condition including at least whether the second state of charge satisfies a preset first state range, wherein, in a case where the charge information satisfies the specified accuracy determination condition, an accuracy of a total state of charge of the battery pack calculated based on the second state of charge is higher than an accuracy of the total state of charge of the battery pack calculated based on the first state of charge; and determining, based on the second state of charge, a target state of charge of the battery cell, if the charge information satisfies the specified accuracy determination condition, the target state of charge being used as a calculation basis for calculating the total state of charge of the battery pack; and determining, based on the first state of charge, the target state of charge of the battery cell, if the charge information does not satisfy the specified accuracy determination condition.

[0007] In a second aspect, some embodiments of the present application provide a device for calculating a state of charge of a battery. The device is applied to a battery pack, and the battery pack includes a battery cell. The device includes an obtaining module, a determining module, a first determining module, and a second determining module. The obtaining module is configured to obtain charge information of the battery cell, the charge information including a first state of charge and a second state of charge of the battery cell, the first state of charge being determined based on a preset integral algorithm, and the second state of charge being determined based on a preset filtering algorithm. The determining module is configured to determine whether the charge information satisfies a specified accuracy determination condition, the specified accuracy determination condition including at least whether the second state of charge satisfies a preset first state range, wherein, in a case where the charge information satisfies the specified accuracy determination condition, an accuracy of a total state of charge of the battery pack calculated based on the second state of charge is higher than an accuracy of the total state of charge of the battery pack calculated based on the first state of charge. The first determining module is configured to determine, based on the second state of charge, a target state of charge of the battery cell, if the charge information satisfies the specified accuracy determination condition, the target state of charge being used as a calculation basis for calculating the total state of charge of the battery pack. The second determining module is configured to determine, based on the first state of charge, the target state of charge of the battery cell, if the charge information does not satisfy the specified accuracy determination condition.

[0008] In a third aspect, some embodiments of the present application further provide a vehicle. The vehicle includes a battery pack, one or more processors, a memory, and one or more application programs. The battery pack includes a battery cell. The one or more application programs are stored in the memory and configured to be executed by the one or more processors, and the one or more programs are configured to execute the method described above.

[0009] In a fourth aspect, the embodiments of the present application further provide a computer readable storage medium, which stores computer program instructions. The computer program instructions can be invoked by a processor to execute the method described above.

[0010] In a fifth aspect, the embodiments of the present application further provide a computer program product, which, when executed, implements the method described above.

[0011] The present application provides a battery state of charge calculation method, device, vehicle and storage medium. The method is applied to a battery pack, and the battery pack includes a battery cell. The method first acquires a first state of charge of the battery cell determined based on a preset integral algorithm and a second state of charge of the battery cell determined based on a preset filtering algorithm, and then determines the second state of charge as the target state of charge of the battery cell in a case where the charging information (i.e., the first state of charge and the second state of charge of the battery cell) meets a specified accuracy judgment condition, i.e., the total state of charge of the battery pack is subsequently calculated based on the second state of charge of the battery cell. In addition, the first state of charge is determined as the target state of charge of the battery cell in a case where the charging information does not meet the specified accuracy judgment condition.

[0012] Since the accuracy of the total state of charge of the battery pack calculated based on the second state of charge as the basis is greater than the accuracy of the total state of charge of the battery pack calculated based on the first state of charge as the basis in the case where the charging information meets the specified accuracy judgment condition, the estimation of the total state of charge of the battery pack by the vehicle can be more accurate, and the real-time SOC of the battery pack can be accurately controlled by the driver during the driving of the vehicle. BRIEF DESCRIPTION OF DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0014] Figure 1 A structural schematic diagram of a vehicle provided by an embodiment of the present application is shown.

[0015] Figure 2 A flowchart of a battery state of charge calculation method provided by a first embodiment of the present application is shown.

[0016] Figure 3 A flowchart of a battery state of charge calculation method provided by a second embodiment of the present application is shown.

[0017] Figure 4A flow diagram of a battery state of charge calculation method provided by a third embodiment of the application is shown.

[0018] Figure 5 A module block diagram of a battery state of charge calculation device provided by an embodiment of the application is shown.

[0019] Figure 6 A module block diagram of a vehicle provided by an embodiment of the application is shown.

[0020] Figure 7 A module block diagram of a computer readable storage medium provided by an embodiment of the application is shown. DETAILED DESCRIPTION

[0021] Embodiments of the application are described below in detail, examples of which are shown in the drawings, in which the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below are exemplary only, and are used only for explanation of the application, and cannot be understood as limiting the application.

[0022] In order to enable those skilled in the art to better understand the scheme of the application, the technical solutions in the embodiments of the application will be described clearly and completely below in conjunction with the drawings in the embodiments of the application. Obviously, the described embodiments are only some of the embodiments of the application, not all. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0023] The application provides a battery state of charge calculation method, device, vehicle and storage medium. The method is applied to a battery pack, and the battery pack includes a battery cell. The method first acquires a first state of charge of the battery cell determined based on a preset integral algorithm and a second state of charge of the battery cell determined based on a preset filtering algorithm, and then determines the second state of charge as a target state of charge of the battery cell in a case where the charging information (i.e., the first state of charge and the second state of charge of the battery cell) meets a specified accuracy judgment condition, i.e., the total state of charge of the battery pack is subsequently calculated by the second state of charge of the battery cell. In addition, the first state of charge is determined as the target state of charge of the battery cell in a case where the charging information does not meet the specified accuracy judgment condition.

[0024] Since the accuracy of the total state of charge of the battery pack calculated based on the second state of charge as the basis is greater than the accuracy of the total state of charge of the battery pack calculated based on the first state of charge as the basis in the case where the charging information meets the specified accuracy judgment condition, the estimation of the total state of charge of the battery pack by the vehicle can be more accurate, and the real-time SOC of the battery pack can be accurately controlled by the driver during the driving of the vehicle.

[0025] To facilitate the detailed description of the application scheme, the application environment in the embodiments of the application will be introduced first in combination with the drawings. Please refer to Figure 1 The battery state of charge calculation method provided in the embodiments of the application is applied to a vehicle 100, which refers to a vehicle driven or pulled by a power device for people to ride or for goods to be transported, including but not limited to a small car, a minibus, a bus, etc. Specifically, the vehicle 100 in the embodiments of the application includes a battery pack 110 and a processor 120.

[0026] The battery pack 110 provides kinetic energy for the vehicle 100. Taking the vehicle 100 as a new energy vehicle for example, the battery pack 110 can provide driving force for the new energy vehicle, and drive the running system (for example, the axle and the wheel) through the transmission system to work. The battery pack 110 in the embodiments of the application includes a plurality of battery cells 1120, which constitute the battery pack 110 by being connected in series with each other or in parallel with each other. Specifically, the battery cell 1120 can be a lithium battery cell, a nickel-hydrogen battery cell, a lithium iron phosphate battery cell, etc., and the specific type and connection mode of the battery cell 1120 are not limited in the embodiments of the application.

[0027] In the embodiments of the application, a plurality of detection devices are also provided in the battery pack 110, which are used to obtain detection data of the battery cell 1120, such as current, voltage, temperature, etc. Specifically, the detection device can include a current sensor (for example, a current transformer, a Hall current sensor and a fluxgate current sensor), a voltage sensor (for example, a Hall voltage sensor, an optical fiber voltage sensor), a temperature sensor (for example, a platinum resistance temperature sensor, a thermocouple temperature sensor and a thermistor temperature sensor), etc., and the specific implementation of the detection device is not limited in the application.

[0028] The processor 120 refers to a processing unit with functions of data reading and data processing. In the embodiments of the application, the processor 120 is electrically connected with the battery pack 110, specifically, the processor 120 is electrically connected with the plurality of detection devices in the battery pack 110, which is used to obtain the detection data of the plurality of battery cells 1120, and then determine the total state of charge of the battery pack 110 based on the detection data. Specifically, the determination method of the total state of charge of the battery pack 110 is described in detail in the method embodiments below.

[0029] It should be noted that the application environment embodiments of the battery state of charge calculation method provided in the embodiments of the application are only illustrative, and the method can also be applied to other vehicles, electrical equipment, electronic equipment, etc. provided with a battery pack, and the embodiments of the application are not limited specifically.

[0030] Please refer toFigure 2 , Figure 2 A method for calculating a state of charge of a battery is schematically shown, which is provided by the first embodiment of the present application and applied to a battery pack including a battery cell. Specifically, the method includes steps S210 to S240.

[0031] In step S210, charge information of the battery cell is obtained.

[0032] In the embodiment, the charge information includes a first state of charge and a second state of charge of the battery cell. The first state of charge is determined based on a preset integral algorithm. As an implementation, the first state of charge can be calculated by a first data processing module corresponding to the battery pack, and the processor can directly read the calculation result of the first data processing module. As another implementation, the processor obtains detection data of the battery cell and determines the first state of charge of the battery cell based on the preset integral algorithm.

[0033] The processor is taken as an example for introduction of the calculation subject. The processor can calculate the first state of charge according to the current of the battery cell. For example, the processor is configured to obtain an actual current value of the battery cell in a current sampling period, and perform integral processing on the actual current value by a preset integral algorithm to obtain the first state of charge of the battery cell. Specifically, the length of the sampling period can be a default value in the processor, and the processor can also adjust the length of the sampling period based on the update frequency of the state of charge of the battery, wherein the length of the sampling period and the update frequency of the state of charge of the battery are in a negative correlation, that is, the higher the update frequency of the state of charge of the battery, the shorter the length of the sampling period.

[0034] The preset integral algorithm can be an ampere-hour integral method, and the calculation formula of the ampere-hour integral method is as follows.

[0035]

[0036] wherein SOC1 is the first state of charge, SOC0 is an initial state of charge of the battery cell, the initial state of charge is a state of charge value corresponding to an initial time of the integral algorithm (i.e., t=0). As an implementation, the initial time of the integral algorithm can be a power-on time of the vehicle, and the processor obtains the state of charge value of the battery cell at the time as the initial state of charge. C is a rated capacity of the battery cell, t is a current time, η is a charge and discharge efficiency of the battery cell, and I is an actual current value of the battery cell corresponding to the current time, wherein the rated capacity and the charge and discharge efficiency of the battery cell are default parameters of the battery cell, and the processor can determine the parameters by reading the related parameter information of the battery cell.

[0037] In this embodiment, the second state of charge is determined based on a preset filtering algorithm. As an implementation manner, the second state of charge can be calculated by a second data processing module corresponding to the battery pack, and the processor can directly read the calculation result of the second data processing module. As another implementation manner, the processor obtains the detection data of the battery cell and determines the second state of charge of the battery cell based on the preset filtering algorithm.

[0038] The processor is taken as an example for introduction of the calculation subject. The processor can calculate the second state of charge according to the current and voltage of the battery cell. For example, the processor is configured to obtain the actual current value and actual voltage value of the battery cell in a current sampling period, and perform filtering processing on the actual current value and actual voltage value by using a preset filtering algorithm to obtain the second state of charge of the battery cell. Specifically, the first state of charge and the second state of charge can be obtained at the same time, or the processor can obtain the second state of charge of the battery cell after determining the first state of charge. The embodiment does not limit the order of obtaining the first state of charge and the second state of charge. The preset filtering algorithm can be a Kalman filter algorithm. The Kalman filter algorithm is an algorithm for optimally estimating the state of a system by using the observation data of the input and output of the system according to the state equation of the linear system. In this embodiment, the observation data of the input and output of the system is the actual current value and actual voltage value of the battery cell, and the state of the system is the second state of charge of the battery cell. Specifically, the expression of the Kalman filter algorithm is as follows.

[0039]

[0040] wherein X(k) is a state variable matrix, in this embodiment, the second state of charge is a certain parameter in the state variable matrix; U(k) is an input variable matrix, that is, the actual current value of the battery cell; W is a process noise matrix; Y(k) is an output variable matrix, that is, the actual voltage value of the battery cell; V is a measurement noise matrix, specifically, W and V can be determined by corresponding noise measurement of the battery pack. A, B, C, D are known quantities, which can be estimated and determined by using an equivalent circuit model. k is the time corresponding to the current sampling period, and k-1 is the time corresponding to the last sampling period, that is, the processor updates the state variable matrix X(k-1) of the last period to obtain X(k) of the current sampling period, that is, the second state of charge.

[0041] Specifically, the Kalman filter algorithm can be an extended Kalman filter (EKF) algorithm, an unscented Kalman filter (UKF) algorithm, or the like. The embodiment does not limit the specific implementation manner of the Kalman filter algorithm.

[0042] Step S220, determining whether the charging information satisfies a specified accuracy determination condition.

[0043] The specified accuracy determination condition at least includes whether the second state of charge satisfies a preset first state range. The preset first state range can be a numerical interval. If the value of the second state of charge is within the numerical interval, it means that the second state of charge satisfies the preset first state range. Conversely, if the value of the second state of charge is not within the numerical interval, it means that the second state of charge does not satisfy the preset first state range. Exemplarily, the numerical interval corresponding to the first state range can be [SOC CLA，min , SOC CLA，max ], wherein the lower limit value SOC CLA，min and the upper limit value SOC CLA，max of the numerical interval can be dynamically adjusted by the processor based on the actual working condition of the vehicle.

[0044] As an implementation manner, the processor determines the numerical interval corresponding to the first state range by obtaining the value of the working condition indication bit of the vehicle and based on a preset first state range mapping table. The first state range mapping table represents the corresponding relationship between the value of the working condition indication bit and the numerical interval corresponding to the first state range. Specifically, the first state range mapping table can be summarized by the researchers based on a large amount of vehicle working condition test data, and the specific determination manner of the first state range mapping table is not limited in the embodiment.

[0045] Since the accuracy of the total state of charge of the battery pack calculated based on the second state of charge as the basis is greater than the accuracy of the total state of charge of the battery pack calculated based on the first state of charge as the basis when the charging information satisfies the specified accuracy determination condition in the embodiment, the estimation of the total state of charge of the battery pack by the processor can be more accurate. Specifically, the researchers found that the accuracy of the total state of charge of the battery pack estimated based on the second state of charge as the basis can be greater than 97%, which ensures that the driver can control the real-time SOC of the battery pack during the driving of the vehicle, and improves the driving experience of the driver.

[0046] Step S230, if the charging information satisfies the specified accuracy determination condition, determining the target state of charge of the battery cell based on the second state of charge.

[0047] The target state of charge is used as a basis for calculating the total state of charge of the battery pack. As an implementation, the processor sends the second state of charge as the target state of charge of the battery cell to the total state of charge calculation module when the charge information meets the specified accuracy determination condition, and the total state of charge calculation module calculates the total state of charge of the battery pack based on the second state of charge. As another implementation, the processor directly calculates the total state of charge of the battery pack based on the second state of charge as the target state of charge of the battery cell when the charge information meets the specified accuracy determination condition. The calculation subject here is exemplified by the processor. As an implementation, the processor stores a weight corresponding to the target state of charge, and the processor takes the product of the target state of charge and the weight as the total state of charge of the battery pack.

[0048] It should be noted that when the second state of charge of the battery cell is calculated by the Kalman filtering algorithm in the current sampling period, i.e., in step S210, the processor updates the state variable matrix X(k) in the Kalman filtering algorithm. When the charge information meets the specified accuracy determination condition, the processor further updates the error covariance matrix, and then takes the updated error covariance matrix P(k) and state variable matrix X(k) as the relevant parameters in the Kalman filtering algorithm in the next sampling period, i.e., completes the update iteration process of the Kalman filtering algorithm. Specifically, the calculation formula of the error covariance matrix is as follows.

[0049] P(k) = (I - K*C)P(k)'.

[0050] Wherein, P(k) is the error covariance matrix, I is the unit matrix, K is the Kalman gain, and P(k)' is the transpose matrix of P(k).

[0051] Step S240, if the charge information does not meet the specified accuracy determination condition, the target state of charge of the battery cell is determined based on the first state of charge.

[0052] Since the charge information does not meet the specified accuracy determination condition, it means that the second state of charge has a large error. In order to ensure the accuracy of the calculation of the total state of charge of the battery pack, the processor determines the target state of charge of the battery cell based on the first state of charge, and in the subsequent process, the total state of charge of the battery pack is calculated based on the first state of charge.

[0053] It should be noted that, in the case that the charging information does not satisfy the specified accuracy determination condition, the processor initializes the state variable matrix X(k) and the error covariance matrix P(k), and takes the initialized state variable matrix X(0) and the initialized error covariance matrix P(0) as the related parameters in the Kalman filtering algorithm in the next sampling period, that is, in the next sampling period, the processor obtains the actual current value and the actual voltage value of the battery cell in the sampling period, and calculates the second state of charge in the next sampling period based on X(0) and P(0). Specifically, X(0) and P(0) are default parameters in the processor. Since the corresponding matrix after updating X(k) and P(k) will also have a large error in the case that the charging information does not satisfy the specified accuracy determination condition, the processor initializes X(k) and P(k) respectively, which can eliminate the error and ensure the accuracy of the calculation of the second state of charge in the subsequent sampling period.

[0054] The application provides a battery state of charge calculation method. The method first obtains a first state of charge of a battery cell determined based on a preset integral algorithm and a second state of charge of the battery cell determined based on a preset filtering algorithm, and then in the case that the charging information (i.e., the first state of charge and the second state of charge of the battery cell) satisfies a specified accuracy determination condition, determines the second state of charge as the target state of charge of the battery cell, that is, the total state of charge of the battery pack is calculated by the second state of charge of the battery cell subsequently. In addition, in the case that the charging information does not satisfy the specified accuracy determination condition, the first state of charge is determined as the target state of charge of the battery cell.

[0055] Since the accuracy of the total state of charge of the battery pack calculated based on the second state of charge is greater than the accuracy of the total state of charge of the battery pack calculated based on the first state of charge in the case that the charging information satisfies the specified accuracy determination condition, the estimation of the total state of charge of the battery pack by the vehicle can be more accurate, and the real-time SOC of the battery pack can be accurately controlled by the driver during the driving of the vehicle.

[0056] Please refer to Figure 3 , Figure 3 The application provides a battery state of charge calculation method. The method first obtains a first state of charge of a battery cell determined based on a preset integral algorithm and a second state of charge of the battery cell determined based on a preset filtering algorithm, and then in the case that the charging information (i.e., the first state of charge and the second state of charge of the battery cell) satisfies a specified accuracy determination condition, determines the second state of charge as the target state of charge of the battery cell, that is, the total state of charge of the battery pack is calculated by the second state of charge of the battery cell subsequently. In addition, in the case that the charging information does not satisfy the specified accuracy determination condition, the first state of charge is determined as the target state of charge of the battery cell.

[0057] Step S310, obtaining the charging information of the plurality of battery cells.

[0058] The plurality of battery cells in the embodiment can be all battery cells in the battery pack, or can be part of the battery cells in the battery pack. As an implementation manner, the processor randomly selects a specified number of battery cells from all battery cells, and obtains a plurality of first state-of-charge corresponding to the plurality of specified number of battery cells, and a plurality of second state-of-charge corresponding to the plurality of specified number of battery cells. Wherein, the specified number is less than the total number of battery cells, and the specified number can be a default value in the processor, and the processor can also adjust the value of the specified number based on the current computing resources of the processor, that is, the more the current computing resources of the processor, the greater the value of the specified number. The obtaining manner of the first state-of-charge and the obtaining manner of the second state-of-charge can refer to the related introduction in step S210, which will not be repeated here. Since the processor in the embodiment only determines the charge information of part of the battery cells, the calculation speed of the processor can be accelerated, and the total state-of-charge of the battery pack can be updated in time subsequently.

[0059] In step S330, if the charge information meets the specified accuracy determination condition, the target state-of-charge of the battery cell is determined based on the second state-of-charge.

[0060] After obtaining the charge information, the processor further judges whether the charge information meets the specified accuracy determination condition, and after obtaining the judgment result, the target state-of-charge of the battery cell obtained can be determined according to the judgment result, so that the estimation of the total state-of-charge of the battery pack is more accurate. In the embodiment, the specified accuracy determination condition can include four determination conditions, which are:

[0061] 1. The plurality of second state-of-charge corresponding to the plurality of battery cells meets the preset first state range;

[0062] 2. In the case of meeting condition 1, the target discharge amount of the battery pack in the preset time is greater than or equal to the specified discharge amount;

[0063] 3. The plurality of first state-of-charge corresponding to the plurality of battery cells is greater than the plurality of second state-of-charge corresponding to the plurality of battery cells;

[0064] 4. In the case of meeting condition 3, the difference between any one first state-of-charge and any one second state-of-charge is greater than or equal to the preset difference.

[0065] The processor determines that the charge information meets the specified accuracy determination condition in the case that the above four determination conditions are all met. Conversely, the processor determines that the charge information does not meet the specified accuracy determination condition in the case that at least one of the above four determination conditions is not met. Specifically, the processor judges whether the charge information meets the specified accuracy determination condition includes the following steps S3301 to S3317.

[0066] In step S3301, the processor determines a maximum value of the second state of charge and a minimum value of the second state of charge based on the plurality of second states of charge corresponding to the plurality of battery cells.

[0067] As an implementation, the processor sorts the plurality of second states of charge corresponding to the plurality of battery cells by using a preset sorting algorithm, and determines the maximum value of the plurality of second states of charge as the maximum value of the second state of charge and the minimum value of the plurality of second states of charge as the minimum value of the second state of charge. Specifically, the preset sorting algorithm can be selection sorting, bubble sorting, insertion sorting, etc., and the present embodiment is not limited in this regard.

[0068] In step S3303, the processor determines that the state of charge information does not satisfy the specified accuracy determination condition in a case where the maximum value of the second state of charge or the minimum value of the second state of charge does not satisfy the first state range.

[0069] The first state range can be referred to the related description in step S220. It should be noted that the first state range in the present embodiment is represented by a numerical interval [SOC CLA，min , SOC CLA，max ], which is summarized by the inventor based on a large amount of battery pack test data. If the plurality of second states of charge are all within the numerical interval, it indicates that the second state of charge calculated by the Kalman filtering algorithm has high accuracy. Conversely, if there is a second state of charge that is not within the numerical interval, it indicates that the calculated second state of charge has certain deviation, and the second state of charge cannot be used to estimate the total state of charge of the battery pack subsequently.

[0070] Specifically, the processor determines that the state of charge information does not satisfy the specified accuracy determination condition in a case where the maximum value of the second state of charge or the minimum value of the second state of charge does not satisfy the first state range, i.e., in a case where or , SOC 2，max is the maximum value of the second state of charge, and SOC 2，min is the minimum value of the second state of charge. In the present embodiment, the processor executes step S370 subsequently in a case where it is determined that the state of charge information does not satisfy the specified accuracy determination condition (i.e., the above-mentioned determination condition 1). Conversely, the processor executes step S3305 in a case where it is determined that the maximum value of the second state of charge and the minimum value of the second state of charge both satisfy the first state range, i.e., in a case where the plurality of second states of charge corresponding to the plurality of battery cells satisfy the preset first state range.

[0071] In the case where the second state-of-charge maximum value and the second state-of-charge minimum value both satisfy the first state range, the processor obtains a target discharge amount of the battery pack within a preset time.

[0072] In the embodiment, in the case where the second state-of-charge maximum value and the second state-of-charge minimum value both satisfy the first state range, that is, in the case where SOC 2，max ∈ [SOC CLA，min , SOC CLA，max ] and SOC 2，min ∈ [SOC CLA，min , SOC CLA，max ], the processor obtains a target discharge amount of the battery pack within a preset time. The preset time can be a default parameter in the processor, or the processor can dynamically adjust the preset time based on the actual working condition of the vehicle.

[0073] As an implementation manner, the processor samples the current change of the battery pack within the preset time to obtain a plurality of sampling currents, and then calculates an average current value corresponding to the plurality of sampling currents. The processor multiplies the average current value by a time length corresponding to the preset time, and determines a result of the multiplication operation as the target discharge amount of the battery pack within the preset time.

[0074] In the case where the target discharge amount is less than a specified discharge amount, the processor determines that the charge information does not satisfy the specified accuracy determination condition.

[0075] The inventors summarize from a large amount of test data of the battery pack that in the case where the target discharge amount of the battery pack within the preset time is greater than or equal to the specified discharge amount, the total state-of-charge of the battery pack estimated based on the second state-of-charge has a high accuracy. Conversely, the total state-of-charge of the battery pack estimated based on the second state-of-charge has a large deviation. Therefore, in the embodiment, in the case where the target discharge amount is less than the specified discharge amount, that is, in the case where AH CAL <Q CAL , the processor determines that the charge information does not satisfy the specified accuracy determination condition (that is, the above-mentioned determination condition 2). Q CAL is the specified discharge amount, which can be a default parameter in the processor, or the processor can dynamically adjust the specified discharge amount based on the actual working condition of the vehicle. In the case where the processor determines that the charge information does not satisfy the specified accuracy determination condition, the processor subsequently executes step S370. Conversely, in the case where the processor determines that the target discharge amount is greater than or equal to the specified discharge amount, the processor executes step S3309.

[0076] Step S3309, in a case where the target discharge amount is greater than or equal to the specified discharge amount, determining, based on the plurality of first states of charge corresponding to the plurality of battery cells, a first state of charge minimum value in the plurality of first states of charge.

[0077] In a case where the target discharge amount is greater than or equal to the specified discharge amount, i.e., in a case where the SOC CAL ≥ Q CAL , the processor determines the first state of charge minimum value based on the plurality of first states of charge corresponding to the plurality of battery cells. As an implementation form, the processor sorts the plurality of first states of charge corresponding to the plurality of battery cells by using a preset sorting algorithm, and determines the minimum value in the plurality of first states of charge as the second state of charge minimum value. Specifically, the preset sorting algorithm can be selection sort, bubble sort, insertion sort, etc., and the present embodiment is not limited in this regard.

[0078] Step S3311, in a case where the first state of charge minimum value is less than or equal to the upper limit value of the first state range, determining that the state of charge information does not satisfy the specified accuracy determination condition.

[0079] The inventors have summarized from a large amount of battery pack test data that in a case where the plurality of first states of charge corresponding to the plurality of battery cells are all greater than the plurality of second states of charge corresponding to the plurality of battery cells, the total state of charge of the battery pack estimated based on the second states of charge has a high accuracy. Conversely, the total state of charge of the battery pack estimated based on the second states of charge has a large deviation. Therefore, in the present embodiment, in a case where the first state of charge minimum value is less than or equal to the upper limit value of the first state range, i.e., in a case where the SOC 1，min ≤ SOC CLA，max , the processor determines that the state of charge information does not satisfy the specified accuracy determination condition (i.e., the above-mentioned determination condition 3). Herein, SOC 1，min is the first state of charge minimum value. In a case where the processor determines that the state of charge information does not satisfy the specified accuracy determination condition, the processor subsequently executes step S370. Conversely, in a case where the first state of charge minimum value is greater than the upper limit value of the first state range, the processor executes step S3313.

[0080] Step S3313, in a case where the first state of charge minimum value is greater than the upper limit value of the first state range, calculating a difference between the first state of charge minimum value and the second state of charge maximum value.

[0081] In a case where the first state of charge minimum value is greater than the upper limit value of the first state range, i.e., in a case where the SOC 1，min > SOC CLA，max , the processor calculates the difference between the first state of charge minimum value and the second state of charge maximum value, i.e., the SOC 1，minSOC 2，max .

[0082] Step S3315, in the case where the difference is greater than or equal to the preset difference, it is determined that the charge information satisfies the specified accuracy determination condition.

[0083] The inventor summarizes from a large number of battery pack test data that in the case where there is a certain difference between the plurality of first state of charges corresponding to the plurality of battery cells and the plurality of second state of charges corresponding to the plurality of battery cells, the total state of charge of the battery pack estimated based on the second state of charge has a high accuracy. On the contrary, the total state of charge of the battery pack estimated based on the second state of charge has a large deviation. Therefore, in the embodiment, the processor determines that the charge information satisfies the specified accuracy determination condition (i.e., the determination conditions 1-4 described above) in the case where the difference is greater than or equal to the preset difference, i.e., in the case where SOC 1，min -SOC 2，max ≥ ΔSOC CLA . The preset difference can be a default parameter in the processor, and the processor can also dynamically adjust the preset difference based on the actual working condition of the vehicle. The processor subsequently executes step S350 in the case where it is determined that the charge information satisfies the specified accuracy determination condition.

[0084] Step S3317, in the case where the difference is less than the preset difference, it is determined that the charge information does not satisfy the specified accuracy determination condition.

[0085] The processor determines that the charge information does not satisfy the specified accuracy determination condition (i.e., the determination condition 4 described above) in the case where the difference is less than the preset difference, i.e., in the case where SOC 1，min -SOC 2，max < ΔSOC CLA . The processor subsequently executes step S370 in the case where it is determined that the charge information does not satisfy the specified accuracy determination condition.

[0086] Step S350, if the charge information satisfies the specified accuracy determination condition, the target state of charge of the battery cell is determined based on the second state of charge.

[0087] In the embodiment, the target state of charge of the battery cell includes a maximum target state of charge and a minimum target state of charge. Specifically, the processor determines the second maximum state of charge as the maximum target state of charge and the second minimum state of charge as the minimum target state of charge in a case where the charging information satisfies the specified accuracy determination condition. The processor can determine the total state of charge of the battery pack based on the maximum target state of charge and the minimum target state of charge, or send the maximum target state of charge and the minimum target state of charge to the total state of charge calculation module, and the total state of charge calculation module calculates the total state of charge of the battery pack based on the maximum target state of charge and the minimum target state of charge.

[0088] In step S370, if the charging information does not satisfy the specified accuracy determination condition, the target state of charge of the battery cell is determined based on the first state of charge.

[0089] In the embodiment, the processor determines the maximum first state of charge and the minimum first state of charge among the first states of charge corresponding to the plurality of battery cells based on the plurality of first states of charge corresponding to the plurality of battery cells in a case where the charging information does not satisfy the specified accuracy determination condition. As an implementation manner, the processor sorts the plurality of first states of charge corresponding to the plurality of battery cells by using a preset sorting algorithm, and determines the maximum value among the plurality of first states of charge as the maximum first state of charge and the minimum value among the plurality of first states of charge as the minimum first state of charge. Specifically, the preset sorting algorithm can be selection sorting, bubble sorting, insertion sorting, etc., which is not limited in the embodiment. The processor further determines the maximum first state of charge as the maximum target state of charge and the minimum first state of charge as the minimum target state of charge. Similarly, in the subsequent process, the processor can determine the total state of charge of the battery pack based on the maximum target state of charge and the minimum target state of charge. The processor can also send the maximum target state of charge and the minimum target state of charge to the total state of charge calculation module, and the total state of charge calculation module determines the total state of charge of the battery pack.

[0090] In some embodiments, the processor is further configured to calculate the total state of charge of the battery pack. Therefore, step S390 is further included after step S350 and step S370, respectively.

[0091] In step S390, the total state of charge of the battery pack is calculated based on a preset weighting algorithm according to the maximum target state of charge and the minimum target state of charge.

[0092] Specifically, the calculation formula of the total state of charge is as follows.

[0093] SOC = k1 * SOC max + k2 * SOC min .

[0094] wherein SOC is the total state of charge of the battery pack, SOC max is the maximum target state of charge, SOC min is the minimum target state of charge, k1 and k2 are weights corresponding to SOC max and SOC min respectively. Specifically, k1 and k2 can be default parameters in the processor, and the processor can also dynamically adjust the weights based on the actual working conditions of the vehicle.

[0095] The application provides a battery state of charge calculation method. In the embodiment, the specified accuracy determination condition is described in detail, so that the accuracy of the total state of charge of the battery pack calculated based on the second state of charge is higher than the accuracy of the total state of charge of the battery pack calculated based on the first state of charge when the specified accuracy determination condition is met, so that the estimation of the total state of charge of the battery pack by the vehicle is more accurate, and the driver can control the real-time SOC of the battery pack during the driving of the vehicle, and the driving experience of the driver is improved.

[0096] Referring to Figure 4 , Figure 4 a battery state of charge calculation method provided by the third embodiment of the application is schematically shown. The method is applied to a battery pack, and the battery pack includes battery cells. Specifically, the method includes steps S410 to S480.

[0097] Step S410: obtaining a first state of charge of the battery cells.

[0098] The specific implementation of step S410 can refer to the related description in step S210, which will not be repeated here.

[0099] Step S420: obtaining at least one state parameter of the battery pack.

[0100] The state parameters include the health state of the battery pack, the battery pack temperature, the battery pack current, and the voltage of the battery cells. Specifically, the battery pack temperature, the battery pack current, and the voltage of the battery cells can be determined by the processor reading the detection data measured by the detection device, and the health state of the battery pack can be determined by the processor reading the health state indication bit corresponding to the battery pack.

[0101] Step S430: when the at least one state parameter is in the corresponding preset range, and the first state of charge meets the preset second state range, then the step of obtaining a second state of charge of the battery cells is performed.

[0102] The inventor summarizes a large number of battery pack test data, and obtains that, in a case that at least one state parameter is in a corresponding preset range, and the first state of charge satisfies a preset second state range, it is indicated that the battery pack is in a good working state, at this time, the second state of charge of the battery cell is obtained, and the total state of charge of the battery pack estimated based on the second state of charge has a high accuracy. Otherwise, it is indicated that the battery pack is in an abnormal working state, that is, the second state of charge of the battery cell obtained has a large error.

[0103] In some embodiments, the state parameter includes a health state of the battery pack, and in a case that a value of a health state indication bit corresponding to the health state is a preset value, that is, St battery ∈{St on，i | i}, the processor determines that the health state of the battery pack is in a corresponding preset range. Wherein, St battery is the value of the health state indication bit, St on，i is the preset value, and i is the number of preset values.

[0104] In some embodiments, the state parameter includes a temperature of the battery pack, and in a case that the temperature of the battery pack is in a preset temperature interval, that is, T current ∈[T on，min , T on，max ], the processor determines that the temperature of the battery pack is in a corresponding preset range. Wherein, T current is the temperature of the battery pack, [T on，min , T on，max ] is the preset temperature interval, and specifically, the lower limit value T on，min and the upper limit value T on，max of the temperature interval can be dynamically adjusted by the processor based on the actual working condition of the vehicle.

[0105] In some embodiments, the state parameter includes a current of the battery pack, and in a case that the current of the battery pack is in a preset current interval, that is, I current ∈[I on，min , I on，max ], the processor determines that the current of the battery pack is in a corresponding preset range. Wherein, I current is the current of the battery pack, [I on，min , I on，max ] is the preset current interval, and specifically, the lower limit value I on，min and the upper limit value I on，maxThe battery pack current in the embodiment is a stable current. As an implementation, the processor samples the current change of the battery pack within a specified time period to obtain a plurality of sampling currents, and then performs filtering operation on the plurality of sampling currents to obtain the stable current. Specifically, the filtering operation can be realized by a preset filtering algorithm, which can be amplitude limiting filtering method, median filtering method, arithmetic average filtering method, etc.

[0106] In some embodiments, the state parameters include the voltage of the battery cell. When the voltage of the battery cell is within a preset voltage interval, i.e., U current ∈ [U on，min , U on，max ], the processor determines that the voltage of the battery cell is within the corresponding preset range. Wherein, U current is the voltage of the battery cell, and [U on，min , U on，max ] is the preset voltage interval. Specifically, the lower limit value U on，min and the upper limit value U on，max of the voltage interval can be dynamically adjusted by the processor based on the actual working condition of the vehicle.

[0107] When all the at least one state parameter is within the corresponding preset range, the processor further determines whether the first state of charge satisfies a preset second state range. When the first state of charge satisfies the preset second state range, the processor performs the step of obtaining the second state of charge of the battery cell, i.e., steps S450 to S480.

[0108] The preset second state range can be a numerical interval. If the value of the first state of charge is within the numerical interval, it means that the first state of charge satisfies the preset second state range. Conversely, if the value of the first state of charge is not within the numerical interval, it means that the first state of charge does not satisfy the preset second state range. Exemplarily, the numerical interval corresponding to the second state range can be [SOC on，min , SOC on，max ], wherein the lower limit value SOC on，min and the upper limit value SOC on，max of the numerical interval can be dynamically adjusted by the processor based on the actual working condition of the vehicle.

[0109] As an implementation, the processor determines the value range corresponding to the second state range based on a preset second state range mapping table by obtaining the value of the working condition indication bit of the vehicle. The second state range mapping table represents the corresponding relationship between the value of the working condition indication bit and the value range corresponding to the second state range. Specifically, the second state range mapping table can be summarized by the R&D personnel based on a large amount of vehicle working condition test data, and the specific determination method of the second state range mapping table is not limited in the embodiment.

[0110] In step S440, if any one of the state parameters is not in the corresponding preset range, or the first state of charge does not satisfy the preset second state range, the target state of charge of the battery cell is determined as the first state of charge.

[0111] In step S440, if any one of the state parameters is not in the corresponding preset range, or the first state of charge does not satisfy the preset second state range, the target state of charge of the battery cell is determined as the first state of charge. Or Or Or In step S440, if any one of the state parameters is not in the corresponding preset range, or the first state of charge does not satisfy the preset second state range, the target state of charge of the battery cell is determined as the first state of charge. In step S440, if any one of the state parameters is not in the corresponding preset range, or the first state of charge does not satisfy the preset second state range, the target state of charge of the battery cell is determined as the first state of charge.

[0112] In the embodiment, the first state of charge of the battery cell and at least one state parameter of the battery pack are obtained first, and then if the first state of charge of the battery cell or the at least one state parameter of the battery pack does not satisfy the corresponding preset range, the subsequent step of obtaining the second state of charge of the battery cell is not executed, so that the computing resources of the processor can be saved.

[0113] In step S450, the second state of charge of the battery cell is obtained.

[0114] In step S460, it is judged whether the charge information satisfies the specified accuracy determination condition.

[0115] In step S470, if the charge information satisfies the specified accuracy determination condition, the target state of charge of the battery cell is determined based on the second state of charge.

[0116] In step S480, if the charge information does not satisfy the specified accuracy determination condition, the target state of charge of the battery cell is determined based on the first state of charge.

[0117] The specific implementation of steps S450 to S480 can refer to the related description in steps S210 to S240, and will not be described here again.

[0118] Please refer to Figure 5 , Figure 5 A structural block diagram of a battery state of charge calculation device 500 provided by an embodiment of the present application is schematically shown. The device 500 is applied to a battery pack including a battery cell, and the device 500 includes an acquisition module 510, a judgment module 520, a first determination module 530, and a second determination module 540. The acquisition module 510 is configured to acquire charge information of the battery cell, the charge information including a first state of charge and a second state of charge of the battery cell, the first state of charge being determined based on a preset integral algorithm, and the second state of charge being determined based on a preset filtering algorithm. The judgment module 520 is configured to judge whether the charge information satisfies a specified accuracy judgment condition, the specified accuracy judgment condition at least including whether the second state of charge satisfies a preset first state range, wherein the accuracy of a total state of charge of the battery pack calculated based on the second state of charge as a basis is greater than the accuracy of the total state of charge of the battery pack calculated based on the first state of charge as a basis in the case where the charge information satisfies the specified accuracy judgment condition. The first determination module 530 is configured to determine a target state of charge of the battery cell based on the second state of charge if the charge information satisfies the specified accuracy judgment condition, the target state of charge being used as a calculation basis for calculating the total state of charge of the battery pack. The second determination module 540 is configured to determine the target state of charge of the battery cell based on the first state of charge if the charge information does not satisfy the specified accuracy judgment condition.

[0119] In some embodiments, the number of battery cells is a plurality, and the judgment module 520 is further configured to determine a maximum second state of charge and a minimum second state of charge in the plurality of second states of charge based on the plurality of second states of charge corresponding to the plurality of battery cells, and determine that the charge information does not satisfy the specified accuracy judgment condition in the case where the maximum second state of charge or the minimum second state of charge does not satisfy the first state range.

[0120] In some embodiments, the judgment module 520 is further configured to acquire a target discharge amount of the battery pack within a preset time in the case where the maximum second state of charge and the minimum second state of charge both satisfy the first state range, and determine that the charge information does not satisfy the specified accuracy judgment condition in the case where the target discharge amount is less than a specified discharge amount.

[0121] In some embodiments, the determining module 520 is further configured to, in a case where the target discharge amount is greater than or equal to the specified discharge amount, determine a first state of charge minimum value from the plurality of first states of charge corresponding to the plurality of battery cells; and in a case where the first state of charge minimum value is less than or equal to the upper limit value of the first state range, determine that the state of charge information does not satisfy the specified accuracy determination condition.

[0122] In some embodiments, the determining module 520 is further configured to, in a case where the first state of charge minimum value is greater than the upper limit value of the first state range, calculate a difference value between the first state of charge minimum value and the second state of charge maximum value; in a case where the difference value is greater than or equal to a preset difference value, determine that the state of charge information satisfies the specified accuracy determination condition; and in a case where the difference value is less than the preset difference value, determine that the state of charge information does not satisfy the specified accuracy determination condition.

[0123] In some embodiments, the obtaining module 510 is further configured to obtain a first state of charge of the battery cell; and obtain at least one state parameter of the battery pack, the state parameter comprising a state of health of the battery pack, a battery pack temperature, a battery pack current, and a voltage of the battery cell. The second obtaining module 520 is further configured to, in a case where the at least one state parameter is all within a corresponding preset range and the first state of charge satisfies a preset second state range, obtain a second state of charge of the battery cell.

[0124] In some embodiments, the second determining module 540 is further configured to, in a case where any one of the state parameters is not within the corresponding preset range or the first state of charge does not satisfy the preset second state range, determine that a target state of charge of the battery cell is the first state of charge, the target state of charge being used as a calculation basis for calculating a total state of charge of the battery pack; and not perform the step of determining whether the state of charge information satisfies the specified accuracy determination condition.

[0125] In some embodiments, the first determining module 530 is further configured to determine the second state of charge maximum value as the maximum target state of charge and determine the second state of charge minimum value as the minimum target state of charge. The second determining module 540 is further configured to determine a first state of charge maximum value and a first state of charge minimum value from the plurality of first states of charge corresponding to the plurality of battery cells; determine the first state of charge maximum value as the maximum target state of charge and determine the first state of charge minimum value as the minimum target state of charge. The apparatus 500 further comprises a total state of charge calculation module (not shown in the figure), which is configured to calculate the total state of charge of the battery pack based on a preset weighting algorithm according to the maximum target state of charge and the minimum target state of charge.

[0126] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the described apparatuses and modules can refer to the corresponding processes in the foregoing method embodiments, which will not be described herein again.

[0127] In several embodiments provided in the present application, the coupling between the modules can be electrical, mechanical or other forms of coupling.

[0128] In addition, each functional module in the embodiments of the present application can be integrated in a processing module, or each module can exist physically independently, or two or more modules can be integrated in one module. The integrated module can be realized in the form of hardware or in the form of a software functional module.

[0129] The present application provides a device for calculating the state of charge of a battery. The device first acquires a first state of charge of a battery cell determined based on a preset integral algorithm and a second state of charge of the battery cell determined based on a preset filtering algorithm, and then determines the second state of charge as a target state of charge of the battery cell in a case where the charge information (i.e., the first state of charge and the second state of charge of the battery cell) satisfies a specified accuracy judgment condition, i.e., the total state of charge of the battery pack is subsequently calculated based on the second state of charge of the battery cell. In addition, the first state of charge is determined as the target state of charge of the battery cell in a case where the charge information does not satisfy the specified accuracy judgment condition.

[0130] Since the accuracy of the total state of charge of the battery pack calculated based on the second state of charge is greater than the accuracy of the total state of charge of the battery pack calculated based on the first state of charge in the case where the charge information satisfies the specified accuracy judgment condition, the estimation of the total state of charge of the battery pack by the vehicle can be more accurate, and the driver can accurately control the real-time SOC of the battery pack during the driving of the vehicle.

[0131] Please refer to Figure 6 which shows that the present application further provides a vehicle 600, which includes one or more processors 610, a memory 620, a battery pack 630, and one or more application programs. The battery pack 630 includes a battery cell, and the one or more application programs are stored in the memory and configured to be executed by the one or more processors, and the one or more application programs are configured to execute the method described in the above embodiments.

[0132] The processor 610 can include one or more processing cores. The processor 610 connects various parts within the entire battery management system through various interfaces and lines, and performs various functions of the battery management system and processes data by running or executing instructions, programs, code sets or instruction sets stored in the memory 620, and calling data stored in the memory 620. Optionally, the processor 610 can be implemented in at least one of a hardware form of a digital signal processing (DSP), a field-programmable gate array (FPGA), and a programmable logic array (PLA). The processor 610 can be integrated with a combination of one or more of a central processing unit (CPU), a graphics processing unit (GPU), and a modem. Among them, the CPU mainly processes operating systems, user interfaces, and application programs; the GPU is responsible for rendering and drawing display content; and the modem is used for processing wireless communication. It can be understood that the above-mentioned modem can also not be integrated into the processor 610, but can be realized by a separate communication chip.

[0133] The memory 620 can include a random access memory (RAM) and can also include a read-only memory (ROM). The memory 620 can be used to store instructions, programs, codes, code sets or instruction sets. The memory 620 can include a program storage area and a data storage area, wherein the program storage area can store instructions for implementing an operating system, instructions for implementing at least one function (for example, a touch function, a sound playing function, an image playing function, etc.), instructions for implementing various method embodiments described above, etc. The data storage area can also store data created by the electronic device in use (for example, a phone book, audio and video data, chat record data, etc.).

[0134] The related introduction of the battery pack 630 can refer to the detailed description in the environmental embodiments in the present application, and will not be repeated here.

[0135] Please refer to Figure 7 which shows that the embodiments of the present application further provide a computer readable storage medium 700, which stores computer program instructions 710, and the computer program instructions 710 can be called by a processor to execute the methods described in the above embodiments.

[0136] The computer readable storage medium 700 can be, for example, a flash memory, an electrically erasable programmable read-only memory (EEPROM), an electrical programmable read only memory (EPROM), a hard disk, or a read-only memory (ROM). Alternatively, the computer readable storage medium comprises a non-transitory computer-readable storage medium. The computer readable storage medium 700 has storage space for computer program instructions 710 to perform any of the method steps described above. These computer program instructions 710 can be read out from or written into one or more computer program products.

[0137] The above merely describes the preferred embodiments of the present application, and is not intended to limit the present application in any form. Although the present application has been disclosed with the preferred embodiments as above, it is not intended to limit the present application. Any person skilled in the art can make some minor changes or modifications to the equivalent embodiments with the above disclosed technical content without departing from the scope of the technical solutions of the present application. Any modification, change, and modification of the above embodiments according to the technical essence of the present application, without departing from the technical solutions of the present application, are still within the scope of the technical solutions of the present application.

Claims

1. A method for calculating the state of charge of a battery, characterized in that, Applied to a battery pack, the battery pack comprising multiple battery cells, the method comprising: The charge information of the battery cell is obtained, including a first state of charge and a second state of charge of the battery cell. The first state of charge is determined based on a preset integration algorithm, and the second state of charge is determined based on a preset filtering algorithm. The method involves determining whether the charge information meets a specified accuracy determination condition. The specified accuracy determination condition includes at least whether the second state of charge (SBC) meets a preset first state range. If the charge information meets the specified accuracy determination condition, the accuracy of the total SBC calculated based on the second SBC is greater than the accuracy of the total SBC calculated based on the first SBC. The determination of whether the charge information meets the specified accuracy determination condition includes: based on multiple second SBCs corresponding to multiple cells, determining a maximum value and a minimum value of the second SBC among the multiple second SBCs; if the maximum value or the minimum value of the second SBC does not meet the first state range, it is determined that the charge information does not meet the specified accuracy determination condition. If the charge information meets the specified accuracy determination condition, then the target charge state of the cell is determined based on the second charge state, and the target charge state is used as the basis for calculating the total charge state of the battery pack. If the charge information does not meet the specified accuracy determination condition, then the target charge state of the cell is determined based on the first charge state.

2. The method according to claim 1, characterized in that, The step of determining whether the charge information meets the specified precision criteria further includes: When both the maximum value of the second state of charge and the minimum value of the second state of charge satisfy the first state range, the target discharge amount of the battery pack within a preset time is obtained. If the target discharge amount is less than the specified discharge amount, it is determined that the charge information does not meet the specified accuracy judgment condition.

3. The method according to claim 2, characterized in that, The step of determining whether the charge information meets the specified precision criteria further includes: When the target discharge amount is greater than or equal to the specified discharge amount, the minimum value of the first state of charge among the multiple first states of charge corresponding to the multiple cells is determined. If the minimum value of the first state of charge is less than or equal to the upper limit of the first state range, it is determined that the charge information does not meet the specified accuracy determination condition.

4. The method according to claim 3, characterized in that, The step of determining whether the charge information meets the specified accuracy criteria also includes: If the minimum value of the first state of charge is greater than the upper limit of the first state range, calculate the difference between the minimum value of the first state of charge and the maximum value of the second state of charge. If the difference is greater than or equal to a preset difference, the charge information is determined to meet the specified accuracy determination condition. If the difference is less than a preset difference, it is determined that the charge information does not meet the specified accuracy determination condition.

5. The method according to any one of claims 1 to 4, characterized in that, The step of obtaining the charge information of the battery cell includes: Obtain the first state of charge of the battery cell; Obtain at least one status parameter of the battery pack, the status parameter including: the health status of the battery pack, the battery pack temperature, the battery pack current, and the voltage of the battery cell; If at least one of the state parameters is within the corresponding preset range, and the first state of charge satisfies the preset second state range, then the second state of charge of the battery cell is obtained.

6. The method according to claim 5, characterized in that, If any of the state parameters is not within the corresponding preset range, or if the first state of charge does not meet the preset second state range, then the target state of charge of the cell is determined to be the first state of charge, and the target state of charge is used as the basis for calculating the total state of charge of the battery pack; and the step of determining whether the charge information meets the specified accuracy determination condition is not performed.

7. The method according to any one of claims 1 to 4, characterized in that, Determining the target state of charge of the battery cell based on the second state of charge includes: determining the maximum value of the second state of charge as the maximum target state of charge, and determining the minimum value of the second state of charge as the minimum target state of charge; Determining the target state of charge of the cell based on the first state of charge includes: Based on the multiple first states of charge corresponding to the multiple battery cells, determine the maximum value and minimum value of the first state of charge among the multiple first states of charge. The maximum value of the first state of charge is determined as the maximum target state of charge, and the minimum value of the first state of charge is determined as the minimum target state of charge. The method further includes: Based on the maximum target state of charge and the minimum target state of charge, the total state of charge of the battery pack is calculated using a preset weighted algorithm.

8. A device for calculating the state of charge of a battery, characterized in that, Applied to a battery pack, the battery pack including multiple battery cells, the device includes: The acquisition module is used to acquire the charge information of the battery cell. The charge information includes a first state of charge and a second state of charge of the battery cell. The first state of charge is determined based on a preset integration algorithm, and the second state of charge is determined based on a preset filtering algorithm. A judgment module is used to determine whether the charge information meets a specified accuracy judgment condition. The specified accuracy judgment condition includes at least whether the second state of charge meets a preset first state range. Wherein, if the charge information meets the specified accuracy judgment condition, the accuracy of the total state of charge of the battery pack calculated based on the second state of charge is greater than the accuracy of the total state of charge of the battery pack calculated based on the first state of charge. Specifically, the judgment module is used to determine the maximum value and the minimum value of the second state of charge among the multiple second states of charge corresponding to multiple cells. If the maximum value or the minimum value of the second state of charge does not meet the first state range, it is determined that the charge information does not meet the specified accuracy judgment condition. The first determining module is used to determine the target state of charge of the cell based on the second state of charge if the charge information meets the specified accuracy determination condition. The target state of charge is used as the basis for calculating the total state of charge of the battery pack. The second determining module is used to determine the target state of charge of the battery cell based on the first state of charge if the charge information does not meet the specified accuracy determination condition.

9. The apparatus according to claim 8, characterized in that, The judgment module is also used to obtain the target discharge amount of the battery pack within a preset time when both the maximum value of the second state of charge and the minimum value of the second state of charge meet the first state range. If the target discharge amount is less than the specified discharge amount, it is determined that the charge information does not meet the specified accuracy judgment condition.

10. The apparatus according to claim 9, characterized in that, The judgment module is further configured to determine the minimum value of the first state of charge among the multiple first states of charge based on the multiple first states of charge corresponding to the multiple cells when the target discharge amount is greater than or equal to the specified discharge amount. If the minimum value of the first state of charge is less than or equal to the upper limit of the first state range, it is determined that the charge information does not meet the specified accuracy determination condition.

11. The apparatus according to claim 10, characterized in that, The judgment module is further configured to calculate the difference between the minimum value of the first state of charge and the maximum value of the second state of charge when the minimum value of the first state of charge is greater than the upper limit of the first state range. If the difference is greater than or equal to a preset difference, the charge information is determined to meet the specified accuracy determination condition. If the difference is less than a preset difference, it is determined that the charge information does not meet the specified accuracy determination condition.

12. A vehicle, characterized in that, include: A battery pack, the battery pack including battery cells; One or more processors; Memory; One or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the one or more processors, the one or more applications being configured to perform the method as described in any one of claims 1-7.

13. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer program instructions that can be invoked by a processor to perform the method as described in any one of claims 1-7.

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