Battery state of charge detection method, battery system, and storage medium

Abstract

The application relates to a battery state-of-charge detection method, a battery system and a storage medium. The method comprises the following steps: obtaining a first initial state-of-charge corresponding to a charging process of a battery based on a first voltage-state-of-charge curve and an initial voltage value; obtaining a second initial state-of-charge corresponding to a discharging process of the battery based on a second voltage-state-of-charge curve and the initial voltage value; obtaining an initial state-of-charge estimation value of the battery according to the first initial state-of-charge and the second initial state-of-charge; if the working state of the battery system is a charging state, obtaining a current time charging current value of the battery, and obtaining a current charging state-of-charge real-time value of the battery according to the current time charging current value, the first initial state-of-charge and a rated capacity of the battery; and if the current charging state-of-charge real-time value is greater than or equal to the initial state-of-charge estimation value, taking the current charging state-of-charge real-time value as an actual current state-of-charge value of the battery. The application has the advantages of short time consumption and high efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery state of charge detection method, a battery system and a storage medium. BACKGROUND

[0002] New energy development has become an inevitable trend, and lithium ion batteries are widely used in electric vehicles, energy storage systems, aerospace and other fields. Therefore, in order to ensure that the battery pack always works in good condition and prolong the cycle life of the battery pack as much as possible, the battery pack must be effectively controlled and managed.

[0003] The main task of the battery management system (BMS) is to ensure that the battery works in the appropriate parameter range. After processing the collected battery pack voltage, temperature, current and other information, the battery pack charging and discharging management, balance control, thermal management and control, battery information display, and fault diagnosis and processing functions are completed. In addition, the state of charge (SOC) of the battery pack, the state of health (SOH), the state of power (SOP) and the state of energy (SOE) are estimated in real time.

[0004] Among them, the battery state of charge is the remaining battery capacity, which is generally expressed in percentage form. Accurate estimation of the state of charge is the most basic and most important task of the battery management system, and many other functions in the system depend on the results of the state of charge estimation. For example, in the field of electric vehicles, accurate estimation of the state of charge can facilitate the system to estimate the remaining mileage and improve driving safety. The state of charge is used to represent the use state of the battery and provides a judgment standard for the use strategy of the battery. In addition, the balance of the battery capacity between the battery monomers is also based on the state of charge. Due to the objective inconsistency between the battery monomers in the battery pack, the phenomenon of unbalanced capacity may occur. The unbalanced capacity will reduce the service life of the battery pack, and the balance control and management of the battery pack based on the state of charge can not only improve the overall capacity of the battery pack, but also help to prolong the battery life. It can be seen that accurate prediction of the battery state of charge is extremely important. However, the open circuit voltage method or the ampere-hour integration method currently used to estimate the battery state of charge either takes a long time or cannot accurately calculate the battery state of charge. SUMMARY

[0005] Therefore, it is necessary to provide a battery state of charge detection method, a battery system and a storage medium which can accurately calculate the battery state of charge in view of the above technical problems.

[0006] A battery state of charge detection method, the method comprising the steps of:

[0007] obtaining a first voltage-state of charge curve of a battery charging process and a second voltage-state of charge curve of a battery discharging process;

[0008] collecting an initial voltage value of the battery when the battery system starts working;

[0009] obtaining a first initial state of charge of the battery corresponding to the charging process based on the first voltage-state of charge curve and the initial voltage value;

[0010] obtaining a second initial state of charge of the battery corresponding to the discharging process based on the second voltage-state of charge curve and the initial voltage value;

[0011] obtaining an initial state of charge estimation value of the battery according to the first initial state of charge and the second initial state of charge;

[0012] if the working state of the battery system is a charging state, obtaining a current time charging current value of the battery, and obtaining a current charging state of charge real-time value of the battery according to the current time charging current value, the first initial state of charge and a rated capacity of the battery;

[0013] if the current charging state of charge real-time value is greater than or equal to the initial state of charge estimation value, taking the current charging state of charge real-time value as a current state of charge actual value of the battery.

[0014] In one of the embodiments, the method further comprises the steps of:

[0015] if the current charging state of charge real-time value is less than the initial state of charge estimation value, updating the first initial state of charge to the current charging state of charge real-time value, and obtaining a next charging state of charge real-time value of the battery according to the current time charging current value, the updated first initial state of charge and the rated capacity of the battery, until the next charging state of charge real-time value is greater than or equal to the initial state of charge estimation value.

[0016] In one of the embodiments, the method further comprises the steps of:

[0017] if the working state of the battery system is a discharging state, obtaining a current time discharging current value of the battery, and obtaining a current discharging state of charge real-time value of the battery according to the current time discharging current value, the second initial state of charge and the rated capacity of the battery;

[0018] if the current discharging state of charge real-time value is less than or equal to the initial state of charge estimation value, taking the current discharging state of charge real-time value as a current state of charge actual value of the battery.

[0019] In one of the embodiments, the method further comprises the steps of:

[0020] If the current discharge state-of-charge real-time value is greater than the initial state-of-charge estimated value, the second initial state-of-charge is updated to the current discharge state-of-charge real-time value, and a next discharge state-of-charge real-time value of the battery is obtained according to the current time discharge current value, the updated second initial state-of-charge and the rated capacity of the battery, until the next discharge state-of-charge real-time value is less than or equal to the initial state-of-charge estimated value.

[0021] In one of the embodiments, the first voltage-state-of-charge curve of the battery charging process and the second voltage-state-of-charge curve of the battery discharging process are obtained based on the following steps:

[0022] The battery is controlled to be empty;

[0023] The battery is controlled to be charged at a preset charging rate for a preset proportion of capacity;

[0024] The battery after charging is controlled to stand for a preset standing time, and after the preset standing time, the first current voltage and the first current residual capacity of the battery are collected;

[0025] According to the first current residual capacity, the first current state-of-charge of the battery is obtained;

[0026] The battery is controlled to be charged at a preset charging rate for a preset proportion of capacity in turn until the battery is fully charged, and a plurality of sets of first current voltage and first current state-of-charge are obtained;

[0027] The plurality of sets of first current voltage and first current state-of-charge are fitted to obtain the first voltage-state-of-charge curve.

[0028] In one of the embodiments, the first voltage-state-of-charge curve of the battery charging process and the second voltage-state-of-charge curve of the battery discharging process are obtained based on the following steps:

[0029] The battery is controlled to be fully charged;

[0030] The battery is controlled to be discharged at a preset discharging rate for a preset proportion of capacity;

[0031] The battery after discharging is controlled to stand for a preset standing time, and after the preset standing time, the second current voltage and the second current residual capacity of the battery are collected;

[0032] According to the second current residual capacity, the second current state-of-charge of the battery is obtained;

[0033] The battery is controlled to be discharged at a preset discharging rate for a preset proportion of capacity in turn until the cut-off voltage of the battery, and a plurality of sets of second current voltage and second current state-of-charge are obtained;

[0034] fitting the plurality of second current time voltage and second current time state of charge, to obtain a second voltage-state of charge curve.

[0035] In one embodiment, if the working state of the battery system is a charging state, a current time charging current value of the battery is obtained, and according to the current time charging current value, the first initial state of charge and the rated capacity of the battery, a current charging state of charge real-time value of the battery is obtained, wherein the current charging state of charge real-time value is obtained according to the following formula:

[0036]

[0037] wherein, represents the current charging state of charge real-time value; represents the first initial state of charge; represents a correction coefficient; represents a charging time point; represents the current time charging current value; represents the rated capacity of the battery.

[0038] In one embodiment, if the working state of the battery system is a discharging state, a current time discharging current value of the battery is obtained, and according to the current time discharging current value, the second initial state of charge and the rated capacity of the battery, a current discharging state of charge real-time value of the battery is obtained, wherein the current discharging state of charge real-time value is obtained according to the following formula:

[0039]

[0040] wherein, represents the current discharging state of charge real-time value; represents the second initial state of charge; represents a correction coefficient; represents a discharging time point; represents the current time discharging current value; represents the rated capacity of the battery.

[0041] A battery system, comprising a battery management module, a battery and a charging and discharging module; the battery management module is electrically connected to the battery and the charging and discharging module respectively; the charging and discharging module is electrically connected to the battery; the battery management module is used to implement the following steps:

[0042] obtaining a first voltage-state of charge curve of a charging process of the battery and a second voltage-state of charge curve of a discharging process of the battery;

[0043] when the battery system starts to work, an initial voltage value of the battery is collected;

[0044] obtaining a first initial state of charge of the battery corresponding to the charging process based on the first voltage-state of charge curve and the initial voltage value;

[0045] obtaining a second initial state of charge of the battery corresponding to the discharging process based on the second voltage-state of charge curve and the initial voltage value;

[0046] obtaining an initial state of charge estimation value of the battery according to the first initial state of charge and the second initial state of charge;

[0047] when the working state of the battery system is the charging state, obtaining a current time charging current value of the battery, and obtaining a current charging state of charge real-time value of the battery according to the current time charging current value, the first initial state of charge and the rated capacity of the battery, if the current charging state of charge real-time value is greater than or equal to the initial state of charge estimation value, then taking the current charging state of charge real-time value as the current state of charge actual value of the battery.

[0048] A computer readable storage medium, having stored thereon a computer program, the computer program being executed by a processor to implement the steps of the foregoing method.

[0049] One of the above technical solutions has the following advantages and beneficial effects:

[0050] The battery state of charge detection method provided by the embodiments of the present application comprises the following steps: collecting an initial voltage value of a battery when the battery system starts to work; obtaining a first initial state of charge corresponding to a charging process of the battery based on a first voltage-state of charge curve and the initial voltage value; obtaining a second initial state of charge corresponding to a discharging process of the battery based on a second voltage-state of charge curve and the initial voltage value; obtaining an initial state of charge estimation value of the battery according to the first initial state of charge and the second initial state of charge; taking the first initial state of charge as an initial value of the state of charge in the charging process of the battery; obtaining a current time charging current value of the battery when the working state of the battery system is a charging state; obtaining a current charging state of charge real-time value of the battery according to the current time charging current value, the first initial state of charge and a rated capacity of the battery; and taking the current charging state of charge real-time value as a current state of charge actual value of the battery if the current charging state of charge real-time value is greater than or equal to the initial state of charge estimation value. Thus, the present application avoids the problem of long detection time caused by long-time static state in the traditional open circuit voltage method, solves the problem that the traditional open circuit voltage method cannot detect the state of charge of the battery in real time, takes the initial state of charge as the initial value of the state of charge detection, avoids the problem that the traditional ampere-hour integral method cannot accurately detect the state of charge due to the inability to accurately obtain the initial value, and in general, the present application has short time consumption, high accuracy, and can easily identify the lagging battery, facilitate the equalization management of the battery, ensure the consistency of the battery, prolong the service life of the battery and increase the efficiency of the unified use of the battery. BRIEF DESCRIPTION OF DRAWINGS

[0051] Figure 1 FIG. 1 is a flowchart of the battery state of charge detection method in the embodiments of the present application.

[0052] Figure 2 FIG. 3 is a flowchart of the step of obtaining the first voltage-state of charge curve in the embodiments of the present application.

[0053] Figure 3 FIG. 5 is a flowchart of the step of obtaining the second voltage-state of charge curve in the embodiments of the present application.

[0054] Figure 4 FIG. 7 is another flowchart of the battery state of charge detection method in the embodiments of the present application.

[0055] Figure 5 FIG. 9 is still another flowchart of the battery state of charge detection method in the embodiments of the present application.

[0056] Figure 6 FIG. 11 is an internal structure diagram of the computer device in the embodiments of the present application. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0058] In order to solve the problem that the current open circuit voltage method or ampere-hour integration method used to estimate the battery state of charge is either time-consuming or cannot accurately calculate the battery state of charge, in one embodiment, Figure 1 As shown, a battery state of charge detection method is provided. The method is described by taking the application of the method to a battery management module in a battery system as an example. The method includes the following steps:

[0059] Step S110 , obtaining a first voltage-state-of-charge curve during a battery charging process and a second voltage-state-of-charge curve during a battery discharging process.

[0060] The first voltage-state-of-charge curve can be a curve with voltage as the horizontal axis and state-of-charge as the vertical axis, and the second voltage-state-of-charge curve can also be a curve with voltage as the horizontal axis and state-of-charge as the vertical axis. Of course, the first voltage-state-of-charge curve can be a curve with voltage as the vertical axis and state-of-charge as the horizontal axis, and the second voltage-state-of-charge curve can also be a curve with voltage as the vertical axis and state-of-charge as the horizontal axis. The first voltage-state-of-charge curve is a curve drawn based on the battery charging process, and the second voltage-state-of-charge curve is a curve drawn based on the battery discharging process. In one example, the first voltage-state-of-charge curve and the second voltage-state-of-charge curve can be pre-stored in a storage medium of the battery management module. In another example, before the method of the present application is executed, an external device (e.g., an external computer device) can send the first voltage-state-of-charge curve and the second voltage-state-of-charge curve to the battery management module.

[0061] In one example, if Figure 2 As shown, a first voltage-state of charge curve is obtained based on the following steps:

[0062] Step S210: Control the battery to be discharged. Discharging means discharging the battery to a cut-off voltage.

[0063] Step S220: Control the battery to charge to a preset proportional capacity at a preset charge rate. The preset charge rate can be determined based on actual needs, for example, the preset charge rate can be 1. The preset proportional capacity can be determined based on actual needs, for example, 10%, 15%, or 20% of the rated capacity.

[0064] Step S230: The charged battery is controlled to rest for a preset rest time. After the preset rest time, the battery's first current voltage and first current remaining capacity are collected. The preset rest time is used to stabilize the battery's voltage and remaining capacity, and can be determined based on actual needs. For example, the preset rest time is 1 hour, 1.5 hours, or 2 hours. After the battery rests for the preset rest time, the first current voltage and first current remaining capacity are collected.

[0065] Step S240: Obtain the first current state of charge of the battery based on the first current remaining capacity. In one example, the first current state of charge is obtained based on the following formula:

[0066] *100%

[0067] in, Indicates the first current state of charge.

[0068] Step S250 controls the battery to be charged sequentially at a preset charge rate for a preset proportional capacity until the battery is fully charged, obtaining multiple sets of first current voltages and first current states of charge. The charging and resting process is repeated multiple times, each time charging at a preset charge rate for a preset proportional capacity. Multiple sets of corresponding first current voltages and first current states of charge are obtained.

[0069] Step S260 , fitting multiple sets of first current voltages and first current states of charge to obtain first voltage-state of charge curves.

[0070] In one example, if Figure 3 As shown, the second voltage-state of charge curve is obtained based on the following steps:

[0071] Step S310: Control the battery to be fully charged. Fully charged means that the battery is charged to 100%.

[0072] Step S320: Control the battery to discharge a preset proportional capacity at a preset discharge rate. The preset discharge rate can be determined based on actual needs, for example, the preset discharge rate can be 1. The preset proportional capacity can be determined based on actual needs, for example, 10%, 15%, or 20% of the rated capacity.

[0073] Step S330: The discharged battery is controlled to stand for a preset rest time. After the preset rest time, the second current voltage and the second current remaining capacity of the battery are collected. The preset rest time is used to stabilize the battery voltage and remaining capacity, and can be determined based on actual needs. For example, the preset rest time is 1 hour, 1.5 hours, or 2 hours. After the battery stands for the preset rest time, the second current voltage and the second current remaining capacity are collected.

[0074] At step S340, a second current state of charge of the battery is obtained according to the second current residual capacity.

[0075] In one example, the first current state of charge is obtained based on the following formula:

[0076] * 100%

[0077] wherein, represents the second current state of charge.

[0078] At step S350, the battery is controlled to discharge a preset proportion of capacity at a preset discharge rate in turn until a cut-off voltage of the battery, and a plurality of sets of second current voltages and second current residual capacities are obtained. The process of discharging and standing is repeated multiple times, and each time the battery is discharged at a preset discharge rate by a preset proportion of capacity. A plurality of sets of second current voltages and second current states of charge corresponding to each other are obtained.

[0079] At step S360, the plurality of sets of second current voltages and second current residual capacities are fitted to obtain a second voltage-state of charge curve.

[0080] At step S120, an initial voltage value of the battery is collected when the battery system starts to work. The battery system is powered on to start to work, and the voltage value of the battery at the power-on time is collected as the initial voltage value. In other words, the start of the battery system to work serves as a starting point for detecting the state of charge of the battery.

[0081] At step S130, a first initial state of charge of the battery corresponding to a charging process is obtained based on the first voltage-state of charge curve and the initial voltage value. The initial voltage value is substituted into the first voltage-state of charge curve to correspondingly obtain the first initial state of charge.

[0082] At step S140, a second initial state of charge of the battery corresponding to a discharging process is obtained based on the second voltage-state of charge curve and the initial voltage value. The initial voltage value is substituted into the second voltage-state of charge curve to correspondingly obtain the second initial state of charge.

[0083] At step S150, an initial state of charge estimation value of the battery is obtained according to the first initial state of charge and the second initial state of charge. The initial state of charge estimation value is a state of charge estimated based on the method of the present application. In one example, an average value of the first initial state of charge and the second initial state of charge is obtained, and the average value is taken as the initial state of charge estimation value.

[0084] In step S160, if the working state of the battery system is the charging state, the current time charging current value of the battery is obtained, and the current charging state of charge real-time value of the battery is obtained according to the current time charging current value, the first initial state of charge and the rated capacity of the battery. The battery system starts to work after being powered on, and the working state of the start of the work is the charging state. The current time charging current value of the battery is collected in real time from the start time as the basis for obtaining the current charging state of charge real-time value of the battery, and the state of charge of the battery is detected in real time.

[0085] After obtaining the current time charging current value, the current charging state of charge real-time value of the battery is obtained according to the current time charging current value, the first initial state of charge and the rated capacity of the battery. In one example, if the working state of the battery system is the charging state, the current time charging current value of the battery is obtained, and the current charging state of charge real-time value of the battery is obtained according to the current time charging current value, the first initial state of charge and the rated capacity of the battery. In step S160, the current charging state of charge real-time value is obtained according to the following formula:

[0086]

[0087] Wherein, The current charging state of charge real-time value is represented by Ic; The first initial state of charge is represented by So; The correction coefficient is represented by K; The charging time point is represented by t; The current time charging current value is represented by I; The rated capacity of the battery is represented by C.

[0088] In step S170, if the current charging state of charge real-time value is greater than or equal to the initial state of charge estimation value, the current charging state of charge real-time value is taken as the current state of charge actual value of the battery. After obtaining the current charging state of charge real-time value, the current charging state of charge real-time value is compared with the initial state of charge estimation value, and when the current charging state of charge real-time value is greater than or equal to the initial state of charge estimation value, the current charging state of charge real-time value is taken as the current state of charge actual value of the battery. For example, Figure 4The battery SOC detection method further includes step S480: if the current real-time SOC value is less than the initial SOC estimate, updating the first initial SOC to the current real-time SOC value, and obtaining the next real-time SOC value of the battery based on the current charging current value, the updated first initial SOC, and the rated capacity of the battery, until the next real-time SOC value is greater than or equal to the initial SOC estimate. In other words, if the current real-time SOC value is less than the initial SOC estimate, the current real-time SOC value is used as the first initial SOC, the real-time SOC value is recalculated, and the next real-time SOC value is obtained. If the next real-time SOC value is greater than or equal to the initial SOC estimate, the next real-time SOC value is used as the current actual SOC value of the battery. If the next real-time SOC value is still less than the initial SOC estimate, the next real-time SOC value is used as the first initial SOC, and the real-time SOC value is recalculated.

[0089] When the real-time state of charge value is less than the estimated initial state of charge value, the first initial state of charge is updated, that is, the starting point of state of charge detection is updated, and the initial value of the calculated state of charge is corrected to avoid error accumulation and improve the accuracy of state of charge detection.

[0090] In one example, if Figure 5 As shown, the battery state of charge detection method further includes the steps of:

[0091] In step S590, if the operating state of the battery system is the discharge state, the current discharge current value of the battery is obtained. Based on the current discharge current value, the second initial state of charge, and the rated capacity of the battery, the current real-time value of the battery's discharge state of charge is obtained. The battery system is powered on and begins operation, and the operating state at power-on is the discharge state. From the moment the battery system begins operation, the current charging current value of the battery is collected in real time as a basis for obtaining the current real-time value of the battery's discharge state of charge, thereby detecting the battery's state of charge in real time.

[0092] After obtaining the current charging current value, the current charging state of charge real-time value of the battery is obtained based on the current charging current value, the second initial state of charge, and the rated capacity of the battery. In one example, when the operating state of the battery system is the discharging state, the current discharge current value of the battery is obtained, and in the step of obtaining the current discharge current value of the battery based on the current discharge current value, the second initial state of charge, and the rated capacity of the battery, the current discharge state of charge real-time value is obtained according to the following formula:

[0093]

[0094] in, Indicates the current real-time value of the discharge and charging status; represents a second initial state of charge; represents the correction factor; Indicates the discharge time point; Indicates the discharge current value at the current time; Indicates the rated capacity of the battery.

[0095] Step S500: If the current real-time value of the discharge state of charge is less than or equal to the initial state of charge estimate, the current real-time value of the discharge state of charge is used as the actual value of the current state of charge of the battery. After obtaining the current real-time value of the discharge state of charge, the current real-time value of the discharge state of charge is compared with the initial state of charge estimate. If the current real-time value of the discharge state of charge is less than or equal to the initial state of charge estimate, the current real-time value of the discharge state of charge is used as the actual value of the current state of charge of the battery. Figure 5 The battery state of charge detection method further includes step S501: if the current real-time state of charge value is greater than the initial state of charge estimate, updating the second initial state of charge to the current real-time state of charge value, and obtaining the next real-time state of charge value of the battery based on the current discharge current value, the updated second initial state of charge, and the rated capacity of the battery, until the next real-time state of charge value is less than or equal to the initial state of charge estimate. In other words, if the current real-time state of charge value is greater than the initial state of charge estimate, the current real-time state of charge value is used as the second initial state of charge, the real-time state of charge value is recalculated, and the next real-time state of charge value is obtained. If the next real-time state of charge value is less than or equal to the more initial state of charge estimate, the next real-time state of charge value is used as the current actual state of charge value of the battery. If the next real-time state of charge value is still greater than the initial state of charge estimate, the next real-time state of charge value is used as the second initial state of charge, and the real-time state of charge value is recalculated.

[0096] When the real-time value of the discharge state of charge is greater than the estimated value of the initial state of charge, the second initial state of charge is updated, that is, the starting point of the state of charge detection is updated, and the initial value of the calculated state of charge is corrected to avoid error accumulation and improve the accuracy of the state of charge detection.

[0097] In each embodiment of the battery state of charge detection method of the present application, when the battery system starts to work, the initial voltage value of the battery is collected, the first initial state of charge corresponding to the charging process of the battery is obtained based on the first voltage-state of charge curve and the initial voltage value, and the second initial state of charge corresponding to the discharging process of the battery is obtained based on the second voltage-state of charge curve and the initial voltage value, then the initial state of charge estimation value of the battery is obtained according to the first initial state of charge and the second initial state of charge, the first initial state of charge is taken as the initial value of the state of charge in the charging process of the battery, when the working state of the battery system is the charging state, the current time charging current value of the battery is obtained, and the current charging state of charge real-time value of the battery is obtained according to the current time charging current value, the first initial state of charge and the rated capacity of the battery, if the current charging state of charge real-time value is greater than or equal to the initial state of charge estimation value, the current charging state of charge real-time value is taken as the current state of charge actual value of the battery. Thus, the present application avoids the problem of long detection time caused by long static time in the traditional open circuit voltage method, solves the problem that the traditional open circuit voltage method cannot detect the state of charge of the battery in real time, and takes the initial state of charge as the initial value of the state of charge detection, avoiding the problem that the traditional ampere-hour integral method cannot accurately detect the state of charge due to the inability to accurately obtain the initial value. In summary, the present application has short time consumption, high accuracy, and is convenient for identifying the lagging battery, balancing management of the battery, ensuring the consistency of the battery, prolonging the service life of the battery and increasing the efficiency of the unified use of the battery. In addition, the present application also solves the problem of the hysteresis characteristic of the battery voltage, and improves the accuracy of the state of charge detection.

[0098] It should be understood that, although Figures 1-5 the steps in the flowchart of the method are shown in the order indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, Figures 1-5 at least part of the steps in the method can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or sub-steps or stages of other steps.

[0099] In one embodiment, a battery system includes a battery management module, a battery and a charge-discharge module; the battery management module is electrically connected to the battery and the charge-discharge module respectively; the charge-discharge module is electrically connected to the battery. The battery management module is used to ensure that the battery works in a proper parameter range, and after processing the collected battery voltage, temperature, current and other information, the battery management module completes the functions of charge-discharge management, balance control, thermal management and control, battery information display, fault diagnosis and processing of the battery pack, and also estimates the state of charge, the state of health, the state of peak power and the state of energy of the battery pack in real time. The battery is used to store and discharge electricity, and has multiple battery units connected in parallel or series. The charge-discharge module is used to control the discharge or charge of the battery.

[0100] The battery management module is used to implement the following steps:

[0101] Obtain a first voltage-state of charge curve of a battery charging process and a second voltage-state of charge curve of a battery discharging process.

[0102] When the battery system starts to work, collect an initial voltage value of the battery.

[0103] Based on the first voltage-state of charge curve and the initial voltage value, obtain a first initial state of charge of the battery corresponding to the charging process.

[0104] Based on the second voltage-state of charge curve and the initial voltage value, obtain a second initial state of charge of the battery corresponding to the discharging process.

[0105] According to the first initial state of charge and the second initial state of charge, obtain an initial state of charge estimation value of the battery.

[0106] If the working state of the battery system is a charging state, obtain a current time charging current value of the battery, and according to the current time charging current value, the first initial state of charge and the rated capacity of the battery, obtain a current charging state of charge real-time value of the battery.

[0107] If the current charging state of charge real-time value is greater than or equal to the initial state of charge estimation value, the current charging state of charge real-time value is taken as the current state of charge actual value of the battery.

[0108] It should be noted that the battery management module is also used for other steps of the battery state of charge detection method.

[0109] In one embodiment, a computer device, which can be a terminal, has an internal structure diagram as shown in Figure 6As shown in the figure. The computer device includes a processor, a memory, a network interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The network interface of the computer device is used to communicate with the external terminal through the network connection. The computer program is executed by the processor to implement a battery state of charge detection method. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer overlaid on the display screen, or a key, trackball or touchpad arranged on the shell of the computer device, or an external keyboard, touchpad or mouse, etc.

[0110] Those skilled in the art can understand that, Figure 6 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0111] In one embodiment, a computer device is provided, comprising a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the following steps:

[0112] Obtaining a first voltage-state of charge curve of a battery charging process and a second voltage-state of charge curve of a battery discharging process;

[0113] When the battery system starts to work, collecting an initial voltage value of the battery;

[0114] Based on the first voltage-state of charge curve and the initial voltage value, obtaining a first initial state of charge of the battery corresponding to the charging process;

[0115] Based on the second voltage-state of charge curve and the initial voltage value, obtaining a second initial state of charge of the battery corresponding to the discharging process;

[0116] According to the first initial state of charge and the second initial state of charge, obtaining an initial state of charge estimation value of the battery;

[0117] If the working state of the battery system is a charging state, obtaining a current time charging current value of the battery, and according to the current time charging current value, the first initial state of charge and the rated capacity of the battery, obtaining a current charging state of charge real-time value of the battery;

[0118] If the current charging state of charge real-time value is greater than or equal to the initial state of charge estimation value, the current charging state of charge real-time value is taken as the current state of charge actual value of the battery.

[0119] In one embodiment, a computer readable storage medium is provided, and the computer program is stored on the computer readable storage medium, and the computer program is executed by a processor to implement the following steps:

[0120] obtaining a first voltage-state of charge curve of a battery charging process and a second voltage-state of charge curve of a battery discharging process;

[0121] When the battery system starts to work, an initial voltage value of the battery is collected;

[0122] Based on the first voltage-state of charge curve and the initial voltage value, a first initial state of charge corresponding to the charging process of the battery is obtained;

[0123] Based on the second voltage-state of charge curve and the initial voltage value, a second initial state of charge corresponding to the discharging process of the battery is obtained;

[0124] According to the first initial state of charge and the second initial state of charge, an initial state of charge estimation value of the battery is obtained;

[0125] If the working state of the battery system is a charging state, a current time charging current value of the battery is obtained, and according to the current time charging current value, the first initial state of charge and the rated capacity of the battery, a current charging state of charge real-time value of the battery is obtained;

[0126] If the current charging state of charge real-time value is greater than or equal to the initial state of charge estimation value, the current charging state of charge real-time value is taken as the current state of charge actual value of the battery.

[0127] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when the computer program is executed, the processes of the above-mentioned embodiments of the methods can be included. Any reference to memory, storage, databases, or other media in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in many forms such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct Rambus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM), etc.

[0128] The technical features of the above embodiments can be combined in any way. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the present application.

[0129] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, some modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. A method for detecting a battery state of charge, characterized in that: The method comprises the following steps: Acquire a first voltage-state-of-charge curve during a battery charging process and a second voltage-state-of-charge curve during a battery discharging process; When the battery system starts working, collect the initial voltage value of the battery; acquiring a first initial state of charge of the battery corresponding to a charging process based on the first voltage-state of charge curve and the initial voltage value; acquiring a second initial state of charge of the battery corresponding to a discharge process based on the second voltage-state of charge curve and the initial voltage value; Obtaining an estimated initial state of charge of the battery according to the first initial state of charge and the second initial state of charge; If the operating state of the battery system is a charging state, obtaining a current charging current value of the battery, and obtaining a current charging state of charge real-time value of the battery based on the current charging current value, the first initial state of charge, and the rated capacity of the battery; If the current charging state of charge real-time value is greater than or equal to the initial state of charge estimated value, the current charging state of charge real-time value is used as the current state of charge actual value of the battery.

2. The battery state of charge detection method according to claim 1, characterized in that: The method further comprises the steps of: If the current charging state of charge real-time value is less than the initial state of charge estimated value, the first initial state of charge is updated to the current charging state of charge real-time value, and the next charging state of charge real-time value of the battery is obtained based on the current time charging current value, the updated first initial state of charge and the rated capacity of the battery, until the next charging state of charge real-time value is greater than or equal to the initial state of charge estimated value.

3. The battery state of charge detection method according to claim 1, characterized in that: The method further comprises the steps of: If the operating state of the battery system is a discharging state, obtaining a current discharge current value of the battery, and obtaining a current discharge state real-time value of the battery based on the current discharge current value, the second initial state of charge, and the rated capacity of the battery; If the current real-time value of the discharge state of charge is less than or equal to the initial state of charge estimation value, the current real-time value of the discharge state of charge is used as the current actual state of charge value of the battery.

4. The battery state of charge detection method according to claim 3, characterized in that: The method further comprises the steps of: If the current real-time value of the discharge state of charge is greater than the estimated value of the initial state of charge, the second initial state of charge is updated to the current real-time value of the discharge state of charge, and the next real-time value of the discharge state of charge of the battery is obtained according to the current time discharge current value, the updated second initial state of charge and the rated capacity of the battery, until the next real-time value of the discharge state of charge is less than or equal to the estimated value of the initial state of charge.

5. The battery state of charge detection method according to claim 1, wherein: In the step of obtaining a first voltage-state-of-charge curve during a battery charging process and a second voltage-state-of-charge curve during a battery discharging process, the first voltage-state-of-charge curve is obtained based on the following steps: Controlling the battery to discharge; Controlling the battery to charge a preset proportional capacity according to a preset charging rate; Controlling the charged battery to stand for a preset rest time, and collecting a first current voltage and a first current remaining capacity of the battery after the preset rest time; acquiring a first current state of charge of the battery according to the first current remaining capacity; Controlling the battery to charge the preset proportional capacity in sequence according to the preset charging rate until the battery is fully charged, and obtaining multiple sets of the first current voltage and the first current state of charge; Fitting is performed on multiple sets of the first current sub-voltages and the first current sub-states of charge to obtain a first voltage-state of charge curve.

6. The battery state of charge detection method according to claim 1, characterized in that: In the step of obtaining a first voltage-state-of-charge curve during a battery charging process and a second voltage-state-of-charge curve during a battery discharging process, the second voltage-state-of-charge curve is obtained based on the following steps: controlling the battery to be fully charged; Controlling the battery to discharge a preset proportional capacity according to a preset discharge rate; Controlling the discharged battery to stand for a preset rest time, and collecting a second current voltage and a second current remaining capacity of the battery after the preset rest time; acquiring a second current state of charge of the battery according to the second current remaining capacity; Controlling the battery to discharge the preset proportional capacity in sequence according to the preset discharge rate until the battery reaches a cut-off voltage, and obtaining multiple sets of the second current voltage and the second current state of charge; Fitting is performed on multiple sets of the second current voltage and the second current state of charge to obtain a second voltage-state of charge curve.

7. The battery state of charge detection method according to any one of claims 1 to 6, characterized in that: If the operating state of the battery system is a charging state, then obtaining the current charging current value of the battery, and obtaining the current charging state of charge real-time value of the battery according to the current charging current value, the first initial state of charge, and the rated capacity of the battery, the current charging state of charge real-time value is obtained according to the following formula: in, Indicates the real-time value of the current charging state of charge; represents a first initial state of charge; represents the correction factor; Indicates the charging time point; Indicates the charging current value at the current time; Indicates the rated capacity of the battery.

8. The battery state of charge detection method according to claim 3 or 4, characterized in that: If the operating state of the battery system is a discharging state, obtaining a current discharge current value of the battery, and obtaining a current discharge state real-time value of the battery based on the current discharge current value, the second initial state of charge, and the rated capacity of the battery, the current discharge state real-time value is obtained according to the following formula: in, Indicates the real-time value of the current discharge and charge state; represents a second initial state of charge; represents the correction factor; Indicates the discharge time point; Indicates the discharge current value at the current time; Indicates the rated capacity of the battery.

9. A battery system, characterized in that: The system comprises a battery management module, a battery and a charge-discharge module; the battery management module is electrically connected to the battery and the charge-discharge module respectively; the charge-discharge module is electrically connected to the battery; the battery management module is used to implement the following steps: Acquire a first voltage-state-of-charge curve during a battery charging process and a second voltage-state-of-charge curve during a battery discharging process; When the battery system starts working, collect the initial voltage value of the battery; acquiring a first initial state of charge of the battery corresponding to a charging process based on the first voltage-state of charge curve and the initial voltage value; acquiring a second initial state of charge of the battery corresponding to a discharge process based on the second voltage-state of charge curve and the initial voltage value; Obtaining an estimated initial state of charge of the battery according to the first initial state of charge and the second initial state of charge; If the operating state of the battery system is a charging state, obtaining a current charging current value of the battery, and obtaining a current charging state of charge real-time value of the battery based on the current charging current value, the first initial state of charge, and the rated capacity of the battery; If the current charging state of charge real-time value is greater than or equal to the initial state of charge estimated value, the current charging state of charge real-time value is used as the current state of charge actual value of the battery.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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