Battery power state determination method, electronic equipment and storage medium

Abstract

The embodiment of the invention provides a battery power state determination method, electronic equipment and a storage medium. The method comprises the following steps: acquiring battery cell sampling data and initial parameters of a battery cell model; determining a first polarization voltage according to the battery cell sampling data; determining a second polarization voltage according to the battery cell sampling data and the initial parameters; according to the first polarization voltage and the second polarization voltage, carrying out correction processing on the initial parameters of the battery cell model to obtain target parameters of the battery cell model; and the battery power state is determined according to the target parameter and the battery cell sampling data, so that the reliability of the battery is improved.

Description

Technical Field

[0001] This application relates to the technical field of battery management, and more particularly to a method for determining the state of power of a battery, an electronic device, and a storage medium. Background Technology

[0002] With the increasing popularity of electric and hybrid vehicles, the precise control of battery state by the battery management system has become one of the core technologies for ensuring vehicle performance and safety. Battery state of power (SOP) is a crucial dynamic parameter in the battery management system. SOP represents the maximum discharge or charge power that the battery system can provide within a specific time period, ensuring that the cells do not experience overcharging, over-discharging, or thermal runaway safety issues when operating at this power.

[0003] The accuracy of battery state of power (SOP) directly affects the vehicle's power response, range, and battery life. For example, in rapid acceleration scenarios, the battery SOP needs to quickly release high power to meet power demands; in low temperature or low remaining charge conditions, power output must be strictly limited to avoid undervoltage risks; and during regenerative braking, charging power needs to be dynamically adjusted to prevent overvoltage. Furthermore, the dynamic characteristics of the battery SOP must adapt to complex and changing driving environments, such as frequent start-stop cycles, continuous uphill driving, or high-speed cruising.

[0004] In the above process, the battery power state relies on static lookup tables or simple switching strategies, making it difficult to balance dynamic performance and safety. When the vehicle experiences sudden changes in power demand, it may experience response delays and uneven power output, resulting in low battery reliability. Summary of the Invention

[0005] This application provides a method for determining the state of power of a battery, an electronic device, and a storage medium to address the problem of low battery reliability in related technologies.

[0006] In a first aspect, embodiments of this application provide a method for determining the state of power of a battery, comprising:

[0007] Obtain the cell sampling data and the initial parameters of the cell model;

[0008] The first polarization voltage is determined based on the cell sampling data;

[0009] The second polarization voltage is determined based on the cell sampling data and initial parameters;

[0010] Based on the first polarization voltage and the second polarization voltage, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model.

[0011] The battery power state is determined based on the target parameters and cell sampling data.

[0012] In one possible implementation, the cell sampling data includes the cell sampling voltage and bus current. Based on the first polarization voltage and the second polarization voltage, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model, including:

[0013] Determine the remaining voltage based on the sampled voltage of the battery cell;

[0014] According to preset conditions, error detection processing is performed on the first polarization voltage to obtain the detection result. The preset conditions are: the first polarization voltage is greater than the first threshold, and the first polarization voltage is greater than the second polarization voltage, and the first polarization voltage is greater than the second threshold. The second threshold is determined based on the remaining voltage.

[0015] Based on the test results, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model.

[0016] In one possible implementation, the initial parameters include ohmic internal resistance and initial polarization resistance. Based on the detection results, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model, including:

[0017] If the detection result shows an error, the first resistance is determined based on the first polarization voltage and the bus current, and the difference between the first resistance and the ohmic internal resistance is determined as the target polarization resistance of the cell model.

[0018] If the test results show no error, the initial polarization resistance is determined as the target polarization resistance.

[0019] The target parameters include the target polarization resistance and the ohmic internal resistance.

[0020] In one possible implementation, determining the battery power state based on target parameters and cell sampling data includes:

[0021] Based on the cell sampling data, determine the attenuation ratio of the polarization voltage;

[0022] The equivalent resistance is determined based on the attenuation ratio, target parameters, and cell sampling data.

[0023] The first limit current is determined based on the equivalent resistance, attenuation ratio, target parameters, and cell sampling data;

[0024] The battery power state is determined based on the first limit current.

[0025] In one possible implementation, the target parameters include the target polarization resistance and the ohmic internal resistance. The equivalent resistance is determined based on the attenuation ratio, the target parameters, and cell sampling data, including:

[0026] Based on the cell sampling data, determine the offset value of the open circuit voltage;

[0027] The polarization voltage attenuation value is determined based on the attenuation ratio and the target polarization resistance.

[0028] The equivalent resistance is determined based on the offset value, polarization voltage attenuation value, and ohmic internal resistance.

[0029] In one possible implementation, the first limit current is determined based on the equivalent resistance, attenuation ratio, target parameters, and cell sampling data, including:

[0030] The polarization voltage correction value is determined based on the cell sampling data and target parameters;

[0031] Determine whether the polarization voltage correction value is greater than or equal to the first preset value, or whether the direction of the current is a preset direction;

[0032] If so, the first limit current is determined based on the equivalent resistance, attenuation ratio, polarization voltage correction value, and cell sampling data;

[0033] If not, the first limit current is determined based on the equivalent resistance and cell sampling data.

[0034] In one possible implementation, determining the battery power state based on a first limit current includes:

[0035] Determine at least one second limit current;

[0036] The minimum limit current among the first limit current and at least one second limit current is determined as the target limit current;

[0037] Determine the battery power state based on the target limit current.

[0038] Secondly, embodiments of this application provide a battery power state determination device, comprising:

[0039] The acquisition module is used to acquire cell sampling data and initial parameters of the cell model;

[0040] The first determining module is used to determine the first polarization voltage based on the cell sampling data;

[0041] The second determining module is used to determine the second polarization voltage based on the cell sampling data and initial parameters;

[0042] The correction module is used to correct the initial parameters of the cell model based on the first polarization voltage and the second polarization voltage to obtain the target parameters of the cell model.

[0043] The third determination module is used to determine the battery power state based on the target parameters and cell sampling data.

[0044] In one possible implementation, the cell sampling data includes the cell sampling voltage and the bus current, and the correction module is specifically used for:

[0045] Determine the remaining voltage based on the sampled voltage of the battery cell;

[0046] According to preset conditions, error detection processing is performed on the first polarization voltage to obtain the detection result. The preset conditions are: the first polarization voltage is greater than the first threshold, and the first polarization voltage is greater than the second polarization voltage, and the first polarization voltage is greater than the second threshold. The second threshold is determined based on the remaining voltage.

[0047] Based on the test results, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model.

[0048] In one possible implementation, the initial parameters include ohmic internal resistance and initial polarization resistance, and the correction module is specifically used for:

[0049] If the detection result shows an error, the first resistance is determined based on the first polarization voltage and the bus current, and the difference between the first resistance and the ohmic internal resistance is determined as the target polarization resistance of the cell model.

[0050] If the test results show no error, the initial polarization resistance is determined as the target polarization resistance.

[0051] The target parameters include the target polarization resistance and the ohmic internal resistance.

[0052] In one possible implementation, the third determining module is specifically used for:

[0053] Based on the cell sampling data, determine the attenuation ratio of the polarization voltage;

[0054] The equivalent resistance is determined based on the attenuation ratio, target parameters, and cell sampling data.

[0055] The first limit current is determined based on the equivalent resistance, attenuation ratio, target parameters, and cell sampling data;

[0056] The battery power state is determined based on the first limit current.

[0057] In one possible implementation, the target parameters include the target polarization resistance and the ohmic internal resistance, and the third determining module is specifically used for:

[0058] Based on the cell sampling data, determine the offset value of the open circuit voltage;

[0059] The polarization voltage attenuation value is determined based on the attenuation ratio and the target polarization resistance.

[0060] The equivalent resistance is determined based on the offset value, polarization voltage attenuation value, and ohmic internal resistance.

[0061] In one possible implementation, the third determining module is specifically used for:

[0062] The polarization voltage correction value is determined based on the cell sampling data and target parameters;

[0063] Determine whether the polarization voltage correction value is greater than or equal to the first preset value, or whether the direction of the current is a preset direction;

[0064] If so, the first limit current is determined based on the equivalent resistance, attenuation ratio, polarization voltage correction value, and cell sampling data;

[0065] If not, the first limit current is determined based on the equivalent resistance and cell sampling data.

[0066] In one possible implementation, the third determining module is specifically used for:

[0067] Determine at least one second limit current;

[0068] The minimum limit current among the first limit current and at least one second limit current is determined as the target limit current;

[0069] Determine the battery power state based on the target limit current.

[0070] Thirdly, embodiments of this application provide an electronic device, including: a memory and a processor;

[0071] The memory stores the instructions that the computer executes;

[0072] The processor executes computer execution instructions stored in memory, causing the processor to perform the first aspect and / or various possible implementations of the first aspect as described above.

[0073] Fourthly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the first aspect and / or various possible implementations of the first aspect.

[0074] Fifthly, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the first aspect and / or various possible implementations of the first aspect.

[0075] This application provides a method, electronic device, and storage medium for determining the state of power (SOP) of a battery. The method involves acquiring cell sampling data and initial parameters of a cell model; determining a first polarization voltage based on the cell sampling data; determining a second polarization voltage based on the cell sampling data and the initial parameters; correcting the initial parameters of the cell model based on the first and second polarization voltages to obtain target parameters for the cell model; and determining the battery SOP based on the target parameters and the cell sampling data. By determining the first and second polarization voltages using cell sampling data and the initial parameters of the cell model, and correcting the initial parameters accordingly, the method achieves accurate calibration of the target parameters of the cell model, thereby improving the accuracy of battery SOP determination and enhancing battery reliability. Attached Figure Description

[0076] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0077] Figure 1 A schematic diagram of the architecture of a battery management system provided in this application;

[0078] Figure 2 A flowchart illustrating a method for determining the state of power of a battery provided in this application. Figure 1 ;

[0079] Figure 3 A flowchart illustrating a method for determining the state of power of a battery provided in this application. Figure 2 ;

[0080] Figure 4 A schematic diagram of a battery power state determination device provided in an embodiment of this application;

[0081] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0082] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0083] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0084] With the increasing popularity of electric and hybrid vehicles, the precise control of battery state by the battery management system has become one of the core technologies for ensuring vehicle performance and safety. Battery state of power (SOP) is a crucial dynamic parameter in the battery management system. SOP represents the maximum discharge or charge power that the battery system can provide within a specific time period, ensuring that the cells do not experience overcharging, over-discharging, or thermal runaway safety issues when operating at this power.

[0085] The accuracy of battery state of power (SOP) directly affects the vehicle's power response, range, and battery life. For example, in rapid acceleration scenarios, the battery SOP needs to quickly release high power to meet power demands; in low temperature or low remaining charge conditions, power output must be strictly limited to avoid undervoltage risks; and during regenerative braking, charging power needs to be dynamically adjusted to prevent overvoltage. Furthermore, the dynamic characteristics of the battery SOP must adapt to complex and changing driving environments, such as frequent start-stop cycles, continuous uphill driving, or high-speed cruising.

[0086] In the above process, the battery power state relies on static lookup tables or simple switching strategies, making it difficult to balance dynamic performance and safety. When the vehicle experiences sudden changes in power demand, it may experience response delays and uneven power output, resulting in low battery reliability.

[0087] This application provides a method for determining the state of power (SOP) of a battery, applied in a battery management system. Based on cell sampling data and initial parameters of the cell model, a dual-path polarization voltage reference is obtained. The initial parameters of the cell model are dynamically corrected by comparing two types of polarization voltages, resulting in target parameters adapted to the actual operating conditions of the cell. These target parameters, along with the sampling data, enable accurate determination of the battery SOP. In this way, by determining the first and second polarization voltages using cell sampling data and initial parameters of the cell model, and correcting the initial parameters accordingly, accurate calibration of the target parameters of the cell model is achieved, thereby improving the accuracy of battery SOP determination and enhancing battery reliability.

[0088] Among them, the battery management system can be applied to power battery systems and adapted to scenarios such as new energy vehicles.

[0089] Battery management systems can be used to achieve precise control of cell status, dynamic adjustment of charging and discharging strategies, and prevention and control of safety risks.

[0090] Below, in conjunction with Figure 1 The battery management system will be explained.

[0091] Figure 1 This application provides a schematic diagram of the architecture of a battery management system, such as... Figure 1 As shown, Figure 1 Includes battery management system 100.

[0092] The battery management system 100 may include a data acquisition unit 101, a calculation and correction unit 102, a control unit 103, and a communication unit 104. Each component unit interacts with signals through a high-speed bus or wired line to form a closed-loop control logic.

[0093] The data acquisition unit 101 can be a basic data input component of the battery management system, and is connected to the power battery cell pack, high voltage circuit and thermal management circuit.

[0094] The data acquisition unit 101 can be used to acquire key status data of the battery cell and system in real time, providing a reliable data source for subsequent calculation and control.

[0095] Key status data may include the voltage of each individual cell, the total voltage of the cell group, the real-time charging and discharging current, and the internal temperature of the cells and battery pack, etc. After data acquisition, the data acquisition unit 101 can also perform preprocessing such as filtering and analog-to-digital conversion on the raw signal, converting the analog signal into a digital signal, and transmitting it to the calculation and correction unit 102 through the communication unit 104. At the same time, key safety parameters are synchronized to the control unit 103 to ensure the real-time nature of safety monitoring.

[0096] The calculation and correction unit 102 may be a processing component of the battery management system.

[0097] The calculation and correction unit 102 may include a cell model, which can be used to calculate cell state parameters and dynamically correct model parameters based on the sampling data of the data acquisition unit 101, and output accurate target parameters of the cell model.

[0098] The specific working process can be based on the mapping table to initially estimate the initial state of charge of the battery cell, and calculate the first polarization voltage and the second polarization voltage based on the initial parameters of the model. Then, by comparing the deviation values ​​of the two polarization voltages, the initial parameters of the model are iteratively corrected in reverse to obtain the target parameters. The target parameters may include ohmic internal resistance, polarization resistance, etc., to ensure that the model accuracy adapts to changes in operating conditions, and at the same time update the initial state of charge estimation results.

[0099] The control unit 103 may be an execution and protection component of the battery management system.

[0100] The control unit 103 can be used to realize charging and discharging power control and all-scenario safety protection based on the target parameters output by the calculation and correction unit 102 and the real-time data of the data acquisition unit 101.

[0101] The control unit 103 can calculate the maximum charge and discharge power limit under the current operating conditions by combining the cell's safe voltage range, output control commands to regulate the charge and discharge current, and dynamically adjust the power limit based on temperature data to balance operating efficiency and safety.

[0102] The control unit 103 can also monitor parameters such as voltage, current, and temperature in real time. When abnormal operating conditions such as overvoltage, overcurrent, and overtemperature are detected, a graded protection mechanism is triggered, and fault data is recorded for subsequent troubleshooting.

[0103] The communication unit 104 can be a signal transmission component of the battery management system.

[0104] The communication unit 104 can adopt the CAN bus communication protocol to realize signal interaction between various components within the system, as well as command and data transmission between the battery management system and external systems.

[0105] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings.

[0106] Figure 2 A flowchart illustrating a method for determining the state of power of a battery provided in this application. Figure 1 ,like Figure 2 As shown, the method includes:

[0107] S201. Obtain the cell sampling data and the initial parameters of the cell model.

[0108] Cell sampling data can refer to the cell operating status data collected in real time by the sampling components of the power battery management system.

[0109] Cell sampling data can include cell sampling voltage, bus current, open circuit voltage (OCV), state of charge (SOC), temperature, etc.

[0110] During the discharge process, the cell sampling voltage can be the minimum voltage value in the cell sampling voltage array of the battery management system, which can be represented as MinV; during the charging process, the cell sampling voltage can be the maximum voltage value in the cell sampling voltage array of the battery management system, which can be represented as MaxV.

[0111] The bus current is positive during discharge and negative during charging.

[0112] The open-circuit voltage can be determined based on the temperature-SOC-OCV three-dimensional table or the SOC-OCV two-dimensional table.

[0113] During discharge, the open-circuit voltage can be determined by consulting the temperature-SOC-OCV three-dimensional table based on the estimated minimum SOC and temperature; during charging, the open-circuit voltage can be determined by consulting the temperature-SOC-OCV three-dimensional table based on the estimated maximum SOC and temperature.

[0114] The initial parameters of the cell model can refer to the baseline parameters of the cell model pre-stored in the battery management system.

[0115] For example, assuming the cell model uses a first-order RC equivalent model, the initial parameters may include ohmic internal resistance, polarization resistance, and time constant.

[0116] Among them, the ohmic internal resistance can be the sum of the body resistance of the electrode material inside the cell, the electrolyte resistance, etc.

[0117] Polarization resistance can be the equivalent resistance generated by the polarization effect during the charging and discharging process of the battery cell.

[0118] The time constant can be used to describe the dynamic rate of change of polarization voltage. Time constant = polarization resistance × polarization capacitance.

[0119] Initial parameters can be obtained through prior multi-condition experiments.

[0120] The system can collect operating data during the operation of the battery cell according to a preset sampling frequency to determine the current battery state. Based on the current battery state, the operating data is preprocessed by filtering, analog-to-digital conversion, etc., to obtain the battery cell sampling data. At the same time, based on the current battery state, the system can call the pre-calibrated initial parameters of the battery cell model from the preset storage space.

[0121] The current battery status is either charging or discharging.

[0122] S202. Determine the first polarization voltage based on the cell sampling data.

[0123] The first polarization voltage can be calculated directly based on the cell sampling data.

[0124] When the battery is currently in a discharged state, the difference between the open-circuit voltage and the cell sampling voltage can be determined as the first polarization voltage.

[0125] When the battery is currently in a charging state, the difference between the cell sampling voltage and the open circuit voltage can be determined as the first polarization voltage.

[0126] S203. Determine the second polarization voltage based on the cell sampling data and initial parameters.

[0127] The second polarization voltage can be the polarization voltage calculated using a cell model.

[0128] The current resistance can be determined based on the internal resistance and polarization resistance, and the second polarization voltage can be determined based on the current resistance and the bus current.

[0129] Optionally, when the current battery state is in a discharging state, the sum of the ohmic internal resistance and the polarization resistance can be determined as the current resistance, and the second polarization voltage can be determined by the product of the current resistance and the bus current; when the current battery state is in a charging state, the sum of the ohmic internal resistance and the polarization resistance can be determined as the current resistance, and the second polarization voltage can be determined by the product of the current resistance and the absolute value of the bus current.

[0130] The current voltage can be determined based on the ohmic internal resistance and the bus current, and the second polarization voltage can be determined based on the open-circuit voltage, the current voltage, and the first peak voltage calculated by the real-time model.

[0131] Optionally, when the current battery state is in a discharging state, the product of the ohmic internal resistance and the bus current can be used to determine the current voltage. Based on the second peak voltage, time constant, polarization resistance, bus current and battery power state operating cycle duration corresponding to the previous cycle, the first peak voltage can be determined. The sum of the current voltage and the first peak voltage can be determined as the first value. The difference between the open circuit voltage and the first value can be determined as the second polarization voltage.

[0132] Among them, the first peak voltage V up It can be determined using the following formula:

[0133] V up =V' up ×exp(-dt / Tao)+Curr×Rp×[1-exp(-dt / Tao)]

[0134] Among them, V' up It can be the second peak voltage corresponding to the previous cycle, dt can be the operating cycle duration of the battery power state, Tao can be the time constant, Curr can be the bus current, and Rp can be the polarization resistor.

[0135] When the current battery state is charging, the product of the ohmic internal resistance and the absolute value of the bus current can be used to determine the current voltage. Based on the second peak voltage, time constant, polarization resistance, absolute value of bus current and operating cycle duration of the battery power state corresponding to the previous cycle, the first peak voltage is determined. The sum of the open circuit voltage, the current voltage and the first peak voltage is used to determine the second polarization voltage.

[0136] Among them, the first peak voltage V up It can be determined using the following formula:

[0137] V up =V' up ×exp(-dt / Tao)+Curr×Rp×[1-exp(-dt / Tao)]

[0138] Among them, V' up It can be the second peak voltage corresponding to the previous cycle, dt can be the operating cycle duration of the battery power state, Tao can be the time constant, Curr can be the absolute value of the bus current, and Rp can be the polarization resistor.

[0139] S204. Based on the first polarization voltage and the second polarization voltage, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model.

[0140] The target parameters can be precise model parameters obtained by dynamically correcting the initial parameters of the cell model through the feedback of the deviation between the first polarization voltage and the second polarization voltage.

[0141] Optionally, the deviation between the first polarization voltage and the second polarization voltage can be determined, and it can be determined whether the deviation exceeds a preset deviation threshold. If the deviation exceeds the preset threshold, the initial parameters of the cell model are optimized by reverse iteration using the least squares method until the deviation between the second polarization voltage and the first polarization voltage calculated based on the corrected parameters is less than or equal to the preset threshold. The corrected parameters are then determined as the target parameters of the cell model. If the deviation does not exceed the preset threshold, the initial parameters are determined as the target parameters.

[0142] Optionally, the remaining voltage is determined based on the sampled voltage of the battery cell; the first polarization voltage is subjected to error detection processing according to preset conditions to obtain the detection result; and the initial parameters of the battery cell model are corrected based on the detection result to obtain the target parameters of the battery cell model.

[0143] The preset conditions are: the first polarization voltage is greater than the first threshold, the first polarization voltage is greater than the second polarization voltage, and the first polarization voltage is greater than the second threshold, wherein the second threshold is determined based on the remaining voltage.

[0144] Among them, when the current battery state is in a discharge state, the remaining voltage can be the difference between the limit voltage and the cell sampling voltage, and the limit voltage can be determined by temperature;

[0145] When the battery is currently in a charging state, the remaining voltage can be the difference between the cell sampling voltage and the limit voltage, which can be determined by temperature.

[0146] The second threshold can be the remaining voltage multiplied by a preset coefficient, and there is no limitation here.

[0147] Optionally, the initial parameters of the cell model can be corrected based on the test results to obtain the target parameters of the cell model as follows: If the test results indicate an error, a first resistance is determined based on the first polarization voltage and the bus current, and the difference between the first resistance and the internal resistance is determined as the target polarization resistance of the cell model; if the test results indicate no error, the initial polarization resistance is determined as the target polarization resistance. The target parameters include the target polarization resistance and the internal resistance.

[0148] Specifically, when the battery is in a discharging state, the first resistor can be determined based on the ratio of the first polarization voltage to the bus current; when the battery is in a charging state, the first resistor can be determined based on the ratio of the absolute value of the first polarization voltage to the bus current.

[0149] S205. Determine the battery power status based on the target parameters and cell sampling data.

[0150] Battery power status can refer to the maximum discharge power that a battery cell can safely output and the maximum charging power that it can safely receive under current operating conditions.

[0151] Based on the target parameters of the cell model and the cell sampling data, and with reference to the preset safe voltage range of the cell, the maximum discharge power or maximum charging power under the current operating conditions can be determined to determine the battery power status.

[0152] Optionally, the attenuation ratio of the polarization voltage can be determined based on the cell sampling data; the equivalent resistance can be determined based on the attenuation ratio, target parameters, and cell sampling data; a first limit current can be determined based on the equivalent resistance, attenuation ratio, target parameters, and cell sampling data; and the battery power state can be determined based on the first limit current.

[0153] This application provides a method for determining the state of power (SOP) of a battery. The method involves acquiring cell sampling data and initial parameters of a cell model; determining a first polarization voltage based on the cell sampling data; determining a second polarization voltage based on the cell sampling data and the initial parameters; correcting the initial parameters of the cell model based on the first and second polarization voltages to obtain target parameters for the cell model; and determining the battery SOP based on the target parameters and the cell sampling data. By determining the first and second polarization voltages using cell sampling data and the initial parameters of the cell model, and correcting the initial parameters accordingly, the method achieves accurate calibration of the target parameters of the cell model, thereby improving the accuracy of battery SOP determination and enhancing battery reliability.

[0154] Below, in conjunction with Figure 3 The process of determining the battery power state based on target parameters and cell sampling data is explained.

[0155] Figure 3 A flowchart illustrating a method for determining the state of power of a battery provided in this application. Figure 2 ,like Figure 3 As shown, the method includes:

[0156] S301. Determine the attenuation ratio of polarization voltage based on the cell sampling data.

[0157] The attenuation ratio of polarization voltage can be a polarization voltage attenuation ratio coefficient, with a value range of (0,1).

[0158] The attenuation ratio of polarization voltage can be used to quantify the dynamic attenuation characteristics of polarization voltage.

[0159] The closer the attenuation ratio is to 1, the slower the polarization voltage decays and the longer the polarization effect lasts.

[0160] The closer the attenuation ratio is to 0, the faster the polarization voltage decays, and the faster the polarization effect disappears.

[0161] Based on the cell sampling data, a fixed duration and time constant can be determined, and based on the fixed duration and time constant, the attenuation ratio of the polarization voltage can be determined.

[0162] Alternatively, the attenuation ratio of the polarization voltage can be determined using the following formula:

[0163] UpFallRatio=exp(-t / tao)

[0164] Where UpFallRatio represents the attenuation ratio of the polarization voltage, exp() represents the natural exponential function, t represents a fixed duration, and tao represents the time constant.

[0165] Alternatively, the fixed duration t can be calculated using the following formula:

[0166]

[0167] Among them, t limit The time corresponding to the limit current can be 2s / 5s / 10s. Pmax can represent the maximum power corresponding to this temperature-state of charge. hold It can represent continuous power, V drop It can represent the power reduction rate, and k can represent a fixed proportionality coefficient.

[0168] S302. Determine the equivalent resistance based on the attenuation ratio, target parameters, and cell sampling data.

[0169] Equivalent resistance can refer to the total equivalent resistance after considering the ohmic internal resistance of the battery cell, polarization resistance, and polarization voltage attenuation characteristics.

[0170] The equivalent resistance can change dynamically with the polarization decay state, which is more in line with the actual operating characteristics of the cell.

[0171] The attenuation ratio, target parameters, and cell sampling data can be input into the equivalent resistance prediction model to obtain the equivalent resistance.

[0172] The equivalent resistance prediction model can be a pre-trained learning model.

[0173] Optionally, the offset value of the open-circuit voltage is determined based on the cell sampling data; the polarization voltage attenuation value is determined based on the attenuation ratio and the target polarization resistance; and the equivalent resistance is determined based on the offset value, the polarization voltage attenuation value, and the internal resistance.

[0174] Alternatively, the equivalent resistance can be determined using the following formula:

[0175] R1=t limit / 3600 / Cact*K OCV +R0+(1-UpFallRatio)*Rp

[0176] Where R1 can represent the equivalent resistance, t limit The current limit can represent the duration corresponding to the current limit, Cact can represent the actual usable capacity of the battery, and K... OCV It can represent the OCV slope, RO can represent the ohmic internal resistance, Rp can represent the target polarization resistance, and UpFallRatio can represent the attenuation ratio of the polarization voltage.

[0177] The equivalent resistance can consist of three parts: the first part is the change in OCV caused by the change in SOC due to the continuous current within the time corresponding to the current limit; the second part can be the instantaneous resistance R0; and the third part can be the new polarization caused by the continuous current within the time corresponding to the current limit.

[0178] S303. Determine the first limit current based on the equivalent resistance, attenuation ratio, target parameters, and cell sampling data.

[0179] The first limit current can be the maximum charge and discharge current threshold that the cell can safely withstand under the current operating conditions, which determines the upper limit of the battery's safe power output.

[0180] The equivalent resistance, attenuation ratio, target parameters, and cell sampling data can be input into the limit current prediction model to obtain the first limit current.

[0181] Among them, the limit current prediction model can be a pre-trained learning model.

[0182] Optionally, a first limit current is determined based on the equivalent resistance, attenuation ratio, target parameters, and cell sampling data; a polarization voltage correction value is determined based on the cell sampling data and target parameters; it is determined whether the polarization voltage correction value is greater than or equal to a first preset value, or whether the current direction is a preset direction; if so, the first limit current is determined based on the equivalent resistance, attenuation ratio, polarization voltage correction value, and cell sampling data; if not, the first limit current is determined based on the equivalent resistance and cell sampling data.

[0183] Alternatively, when the battery is currently in a discharged state, the polarization voltage correction value can be determined using the following formula:

[0184] Up = OCV - MinV - Curr * R0

[0185] Where Up can represent the polarization voltage correction value, OCV can represent the open circuit voltage, MinV can represent the cell sampling voltage, Curr can represent the bus current, and R0 can represent the internal resistance in ohms.

[0186] When the battery is currently in a charging state, the polarization voltage correction value can be determined using the following formula:

[0187] Up = MaxV - OCV - (-Curr) * R0

[0188] Where Up can represent the polarization voltage correction value, OCV can represent the open circuit voltage, MaxV can represent the cell sampling voltage, Curr can represent the bus current, and R0 can represent the internal resistance in ohms.

[0189] Optionally, when the battery is currently in a discharged state, the first limit current can be determined using the following formula based on the equivalent resistance, attenuation ratio, polarization voltage correction value, and cell sampling data:

[0190] I1=(OCV- Up*UpFallRatio-V1) / R1

[0191] Where I1 can represent the first limit current, OCV can represent the open circuit voltage, Up can represent the polarization voltage correction value, UpFallRatio can represent the polarization voltage attenuation ratio, V1 can represent the discharge voltage limit, and R1 can represent the equivalent resistance.

[0192] When the battery is currently in a charging state, the first limit current can be determined using the following formula based on the equivalent resistance, attenuation ratio, polarization voltage correction value, and cell sampling data:

[0193] I1=(V2-OCV- Up*UpFallRatio) / R1

[0194] Where I1 can represent the first limit current, OCV can represent the open circuit voltage, Up can represent the polarization voltage correction value, UpFallRatio can represent the polarization voltage attenuation ratio, V2 can represent the charging voltage limit, and R1 can represent the equivalent resistance.

[0195] Optionally, when the battery is currently in a discharged state, the first limit current can be determined using the following formula based on the equivalent resistance and cell sampling data:

[0196] I1 = (OCV - V1) / R1

[0197] Where I1 can represent the first limit current, OCV can represent the open circuit voltage, V1 can represent the discharge voltage limit, and R1 can represent the equivalent resistance.

[0198] When the battery is currently in a charging state, the first limit current can be determined using the following formula based on the equivalent resistance and cell sampling data:

[0199] I1 = (V2 - OCV) / R1

[0200] Where I1 can represent the first limit current, OCV can represent the open circuit voltage, V2 can represent the charging voltage limit, and R1 can represent the equivalent resistance.

[0201] S304. Determine the battery power state based on the first limit current.

[0202] The number of batteries connected in series can be obtained, and the battery power state can be determined based on the first limit current and the number of batteries connected in series.

[0203] Optionally, the battery power state can be determined based on the first limit current by: determining at least one second limit current; determining the minimum limit current among the first limit current and at least one second limit current as the target limit current; and determining the battery power state based on the target limit current.

[0204] Among them, at least one second limit current may include a current limit to prevent excessive temperature, a maximum electrical limit of the battery system, a current limit to prevent lithium plating in the cell, or other current limits to protect battery life, etc.

[0205] Optionally, when the current battery state is in a discharge state, the battery power state can be determined according to the target limit current in the following way: obtain the corresponding voltage and the number of batteries connected in series at the corresponding time of the limit current, determine the first product of the corresponding voltage, the number of batteries connected in series and the target limit current at the corresponding time, and determine the ratio of the first product to a preset value as the limit power corresponding to the battery power state.

[0206] Optionally, when the current battery state is charging, the battery power state can be determined based on the target limit current in the following manner: obtain the number of batteries connected in series, determine the second product of the ohmic internal resistance and the target limit current, determine the first sum of the second product and the open circuit voltage, determine the third product of the first sum, the target limit current and the number of batteries connected in series, and determine the ratio of the third product to a preset value as the limit power corresponding to the battery power state.

[0207] The preset value can be 1000.

[0208] The implementation details of each step in this application embodiment can be found in the description of the corresponding steps or operations in the above method embodiments; repeated content will not be repeated.

[0209] This application provides a method for determining the state of power (SOP) of a battery. The method involves determining the attenuation ratio of the polarization voltage based on cell sampling data; determining the equivalent resistance based on the attenuation ratio, target parameters, and cell sampling data; determining a first limit current based on the equivalent resistance, attenuation ratio, target parameters, and cell sampling data; and determining the battery SOP based on the first limit current. This improves the accuracy of SOP determination and enhances battery reliability.

[0210] Figure 4 This is a schematic diagram of a battery power state determination device provided in an embodiment of this application. Please refer to... Figure 4 The battery power state determination device 400 includes an acquisition module 401, a first determination module 402, a second determination module 403, a correction module 404, and a third determination module 405.

[0211] The acquisition module 401 is used to acquire the cell sampling data and the initial parameters of the cell model;

[0212] The first determining module 402 is used to determine the first polarization voltage based on the battery cell sampling data;

[0213] The second determining module 403 is used to determine the second polarization voltage based on the cell sampling data and initial parameters;

[0214] The correction module 404 is used to correct the initial parameters of the cell model based on the first polarization voltage and the second polarization voltage to obtain the target parameters of the cell model.

[0215] The third determining module 405 is used to determine the battery power state based on the target parameters and the cell sampling data.

[0216] In one possible implementation, the cell sampling data includes the cell sampling voltage and the bus current, and the correction module 404 is specifically used for:

[0217] Determine the remaining voltage based on the sampled voltage of the battery cell;

[0218] According to preset conditions, error detection processing is performed on the first polarization voltage to obtain the detection result. The preset conditions are: the first polarization voltage is greater than the first threshold, and the first polarization voltage is greater than the second polarization voltage, and the first polarization voltage is greater than the second threshold. The second threshold is determined based on the remaining voltage.

[0219] Based on the test results, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model.

[0220] In one possible implementation, the initial parameters include ohmic internal resistance and initial polarization resistance, and the correction module 404 is specifically used for:

[0221] If the detection result shows an error, the first resistance is determined based on the first polarization voltage and the bus current, and the difference between the first resistance and the ohmic internal resistance is determined as the target polarization resistance of the cell model.

[0222] If the test results show no error, the initial polarization resistance is determined as the target polarization resistance.

[0223] The target parameters include the target polarization resistance and the ohmic internal resistance.

[0224] In one possible implementation, the third determining module 405 is specifically used for:

[0225] Based on the cell sampling data, determine the attenuation ratio of the polarization voltage;

[0226] The equivalent resistance is determined based on the attenuation ratio, target parameters, and cell sampling data.

[0227] The first limit current is determined based on the equivalent resistance, attenuation ratio, target parameters, and cell sampling data;

[0228] The battery power state is determined based on the first limit current.

[0229] In one possible implementation, the target parameters include the target polarization resistance and the ohmic internal resistance, and the third determining module 405 is specifically used for:

[0230] Based on the cell sampling data, determine the offset value of the open circuit voltage;

[0231] The polarization voltage attenuation value is determined based on the attenuation ratio and the target polarization resistance.

[0232] The equivalent resistance is determined based on the offset value, polarization voltage attenuation value, and ohmic internal resistance.

[0233] In one possible implementation, the third determining module 405 is specifically used for:

[0234] The polarization voltage correction value is determined based on the cell sampling data and target parameters;

[0235] Determine whether the polarization voltage correction value is greater than or equal to the first preset value, or whether the direction of the current is a preset direction;

[0236] If so, the first limit current is determined based on the equivalent resistance, attenuation ratio, polarization voltage correction value, and cell sampling data;

[0237] If not, the first limit current is determined based on the equivalent resistance and cell sampling data.

[0238] In one possible implementation, the third determining module 405 is specifically used for:

[0239] Determine at least one second limit current;

[0240] The minimum limit current among the first limit current and at least one second limit current is determined as the target limit current;

[0241] Determine the battery power state based on the target limit current.

[0242] This embodiment provides a battery power state determination device that can execute the method provided in the above-described method embodiment. Its implementation principle and technical effect are similar, and will not be described in detail here.

[0243] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Please refer to... Figure 5 Electronic device 500 may include: memory 501, processor 502, and transceiver 503.

[0244] Memory 501 is used to store program instructions;

[0245] The processor 502 is used to execute the program instructions stored in the memory so that the electronic device 500 performs the above-described method.

[0246] Transceiver 503 may include a transmitter and / or a receiver. The transmitter may also be referred to as a transmitter, transmitter port, or transmitter interface, and the receiver may also be referred to as a receiver port, receiver interface, or similar descriptions. Exemplarily, memory 501, processor 502, and transceiver 503 are interconnected via bus 504.

[0247] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0248] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0249] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0250] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0251] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described method.

[0252] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0253] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0254] The division of units is merely a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0255] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0256] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0257] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0258] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0259] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A method for determining the state of power of a battery, characterized in that, include: Obtain the cell sampling data and the initial parameters of the cell model; The first polarization voltage is determined based on the cell sampling data; The second polarization voltage is determined based on the cell sampling data and the initial parameters; Based on the first polarization voltage and the second polarization voltage, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model; The battery power state is determined based on the target parameters and the cell sampling data.

2. The method according to claim 1, characterized in that, The cell sampling data includes cell sampling voltage and bus current. Based on the first polarization voltage and the second polarization voltage, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model, including: The remaining voltage is determined based on the sampled voltage of the battery cell; According to preset conditions, the first polarization voltage is subjected to error detection processing to obtain a detection result. The preset conditions are: the first polarization voltage is greater than a first threshold, the first polarization voltage is greater than a second polarization voltage, and the first polarization voltage is greater than a second threshold. The second threshold is determined based on the remaining voltage. Based on the detection results, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model.

3. The method according to claim 2, characterized in that, The initial parameters include ohmic internal resistance and initial polarization resistance. Based on the detection results, the initial parameters of the cell model are corrected to obtain the target parameters of the cell model, including: If the detection result indicates an error, a first resistance is determined based on the first polarization voltage and the bus current, and the difference between the first resistance and the ohmic internal resistance is determined as the target polarization resistance of the cell model. If the detection result indicates that there is no error, the initial polarization resistance is determined as the target polarization resistance; The target parameters include the target polarization resistance and the ohmic internal resistance.

4. The method according to any one of claims 1-3, characterized in that, Determining the battery power state based on the target parameters and the cell sampling data includes: Based on the cell sampling data, determine the attenuation ratio of the polarization voltage; The equivalent resistance is determined based on the attenuation ratio, the target parameter, and the cell sampling data. The first limit current is determined based on the equivalent resistance, the attenuation ratio, the target parameter, and the cell sampling data. The battery power state is determined based on the first limit current.

5. The method according to claim 4, characterized in that, The target parameters include the target polarization resistance and the internal resistance in ohms. Based on the attenuation ratio, the target parameters, and the cell sampling data, the equivalent resistance is determined, including: Based on the cell sampling data, determine the offset value of the open circuit voltage; The polarization voltage attenuation value is determined based on the attenuation ratio and the target polarization resistance; The equivalent resistance is determined based on the offset value, the polarization voltage attenuation value, and the ohmic internal resistance.

6. The method according to claim 4, characterized in that, Determining the first limit current based on the equivalent resistance, the attenuation ratio, the target parameter, and the cell sampling data includes: Based on the cell sampling data and the target parameters, determine the polarization voltage correction value; Determine whether the polarization voltage correction value is greater than or equal to a first preset value, or whether the direction of the current is a preset direction; If so, the first limit current is determined based on the equivalent resistance, the attenuation ratio, the polarization voltage correction value, and the cell sampling data; If not, then the first limit current is determined based on the equivalent resistance and the cell sampling data.

7. The method according to claim 4, characterized in that, Determining the battery power state based on the first limit current includes: Determine at least one second limit current; The minimum limit current among the first limit current and the at least one second limit current is determined as the target limit current; The battery power state is determined based on the target limit current.

8. An electronic device, characterized in that, include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the method as described in any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1 to 7.

10. A computer program product, characterized in that, Includes a computer program that, when executed by a processor, implements the method according to any one of claims 1-7.

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