Method for determining state of charge of a battery, battery and vehicle

Abstract

This application provides a method for determining the state of charge (SOC) of a battery, a battery, and a vehicle. During the dormant period of the battery management system (BMS), the method detects the battery's current data and a wake-up signal for waking up the battery. In response to meeting SOC calibration conditions, the method calibrates the battery's first SOC based on the current data to obtain a second SOC. The SOC calibration conditions include that the number of recorded wake-up signals is not less than a preset threshold. The first SOC is the charge state when the BMS begins its dormant period. This allows for calibration of the first SOC based on the battery's current data during the dormant period, thereby reducing false triggering of SOC updates and improving the accuracy of SOC update triggering.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of battery management, and particularly relate to a method for determining state of charge of a battery, a battery and a vehicle. BACKGROUND

[0002] With the development of battery management technology, the requirement for SOC estimation accuracy is also higher and higher. In the related art, the state of charge (SOC) of a battery can be determined by recording the current dynamics of the battery.

[0003] However, it is found through long-term research of the inventors that the determined SOC is not accurate enough in some cases. SUMMARY

[0004] Embodiments of the present application provide a method for determining state of charge of a battery, a battery and a vehicle, aiming at improving the technical problem that the determined SOC is not accurate enough in some cases, and improving the accuracy of the determined SOC.

[0005] In a first aspect, a method for determining state of charge of a battery is provided, comprising: detecting current data of the battery and detecting a wake-up signal for waking up the battery during a sleep period of a battery management system; in response to satisfying a state of charge calibration condition, calibrating a first state of charge of the battery based on the current data to obtain a second state of charge of the battery, the state of charge calibration condition comprising that a number of recorded wake-up signals is not less than a preset number threshold, and the first state of charge being a state of charge when the battery management system starts to sleep.

[0006] In this embodiment, during the sleep period of the battery management system, the battery current data and the wake-up signal for waking up the battery are detected; it is determined whether the state of charge (SCC) calibration conditions are met, including that the number of recorded wake-up signals is not less than a preset threshold number; in response to meeting the SCC calibration conditions, the first SCC of the battery is calibrated based on the current data to obtain the second SCC of the battery. The first SCC is the charge state when the battery management system begins to sleep. In this way, the battery current data during the period when the battery management system is in sleep mode can be detected, and the first SCC is calibrated based on the battery current data during the period when the SCC is in sleep mode is only when the SCC calibration conditions are met (e.g., the number of recorded wake-up signals for waking up the battery is not less than a preset threshold number) to obtain the second SCC. This eliminates the need for constant SCC calibration, and instead, the battery SCC is calibrated only when the number of recorded wake-up signals for waking up the battery is not less than a preset threshold number. This reduces false triggering of battery SCC update and improves the accuracy of battery SCC update triggering. Furthermore, since the state of charge is calibrated using battery current data during the period when the battery management system is in a dormant state, the accuracy of the determined SOC can be improved.

[0007] In one possible implementation, the wake-up signal includes at least one of a tailgate trigger signal and a door trigger signal of the vehicle to which the battery is installed, wherein the tailgate trigger signal is used to indicate that the tailgate is switched from a closed state to an open state, and the door trigger signal is used to indicate that the door is switched from a closed state to an open state.

[0008] In this embodiment, the wake-up signal includes at least one of the tailgate trigger signal and the door trigger signal of the vehicle where the battery is installed. The tailgate trigger signal is used to indicate that the tailgate switches from a closed state to an open state, and the door trigger signal is used to indicate that the door switches from a closed state to an open state. In this way, the SOC calibration can be triggered by the trigger signals of the vehicle's tailgate and / or door, thereby enabling a more accurate determination of the SOC calibration of the battery, which is beneficial to improving the use of the battery after it is installed in the vehicle.

[0009] In one possible implementation, the positive and negative terminals of the battery are used to connect to the vehicle's load, the battery's battery management system is used to connect to one end of the tailgate control switch, the other end of the tailgate control switch is grounded, and the tailgate control switch is used to control the tailgate to switch from a closed state to an open state when closed; the method also includes: detecting a tailgate trigger signal through the battery's battery management system, the tailgate trigger signal being a signal sent to the battery when the tailgate control switch is closed.

[0010] In this embodiment, the positive and negative terminals of the battery are used to connect to the vehicle's load, the battery's battery management system is used to connect to one end of the tailgate control switch, and the other end of the tailgate control switch is grounded. The tailgate control switch is used to control the tailgate to switch from the closed state to the open state when it is closed. In this way, the tailgate trigger signal can be detected by the battery management system, which improves the convenience of detecting the tailgate trigger signal and does not rely on other hardware.

[0011] In one possible implementation, the method further includes: when a preset signal is detected, determining the duration of the preset signal; if the duration of the preset signal is greater than a duration threshold, then recording the preset signal as a wake-up signal; if the duration of the preset signal is not greater than the duration threshold, then not recording the preset signal.

[0012] In this embodiment, when a preset signal is detected, the duration of the preset signal is determined. If the duration of the preset signal is greater than the duration threshold, the preset signal is recorded as a wake-up signal. If the duration of the preset signal is not greater than the duration threshold, the preset signal is not recorded. This reduces the possibility of false wake-up signal judgment due to signal jitter, thereby improving the accuracy of wake-up signal recording, which is beneficial for improving the accuracy of SOC determination and reducing the required storage resources.

[0013] In one possible implementation, the method further includes: determining the detection interval between any two detected wake-up signals; if the detection interval between any two wake-up signals is greater than a time interval threshold, then recording any two wake-up signals; if the detection interval between any two wake-up signals is not greater than the time interval threshold, then recording one of the two wake-up signals.

[0014] In this embodiment, the detection interval between any two detected wake-up signals is determined; if the detection interval between any two wake-up signals is greater than the time interval threshold, then any two wake-up signals are recorded; if the detection interval between any two wake-up signals is not greater than the time interval threshold, then one of the two wake-up signals is recorded. This reduces the possibility of false wake-up signal recording, improves the accuracy of wake-up signal recording, and helps improve the trigger accuracy of SOC calibration.

[0015] In one possible implementation, the method further includes: if the current value in the current data is greater than a current threshold, then the current value is deleted from the current data.

[0016] This embodiment removes abnormal current values ​​from the current data if the current value in the current data is greater than the current threshold, thereby filtering out abnormal current values ​​and improving the accuracy of the determined SOC.

[0017] In one possible implementation, calibrating the first state of charge (SOC) based on current data to obtain the second SOC of the battery includes: determining the change in charge of the battery during the dormant period of the battery management system based on the current data; determining the change in SOC of the battery during the dormant period of the battery management system based on the change in charge of the battery during the dormant period of the battery management system, wherein the change in SOC is positively correlated with the change in charge; and determining the second SOC of the battery based on the first SOC and the change in SOC, wherein the second SOC is positively correlated with the first SOC and negatively correlated with the change in SOC.

[0018] In this embodiment, the change in battery charge during the sleep period of the battery management system is determined based on current data; the change in state of charge (SOC) during the sleep period of the battery management system is determined based on the change in battery charge during the sleep period of the battery management system, and the change in SOC is positively correlated with the change in charge; the second SOC of the battery is determined based on the first SOC and the change in SOC, and the second SOC is positively correlated with the first SOC and negatively correlated with the change in SOC, which makes the accuracy of the calibrated second SOC higher.

[0019] In one possible implementation, the method is executed by the battery management system, which, in response to satisfying the state of charge calibration conditions, calibrates the first state of charge of the battery based on current data to obtain the second state of charge of the battery, including: when the battery management system is in a wake-up state, in response to satisfying the state of charge calibration conditions, calibrating the first state of charge of the battery based on current data to obtain the second state of charge of the battery.

[0020] In this example, when the battery management system is in a wake-up state, in response to meeting the state of charge (SOC) calibration conditions, it acquires the battery's first state of charge (SOC) and the battery's current data during the battery management system's sleep period. Based on the battery's current data during the sleep period, the first SOC is calibrated to obtain the second SOC. This means that the battery management system only acquires the first SOC and the battery's current data during the sleep period when it needs to manage the battery based on the SOC. The calibration of the first SOC based on the battery's current data during the sleep period reduces false triggering of SOC calibration and improves the resource utilization of the battery management system.

[0021] Secondly, embodiments of this application propose a device for determining the state of charge (SOC) of a battery, comprising: a detection module for detecting current data of the battery and detecting a wake-up signal for waking up the battery during the dormant period of the battery management system; and a calibration module for calibrating a first SOC of the battery based on the current data in response to meeting SOC calibration conditions, thereby obtaining a second SOC of the battery, wherein the SOC calibration conditions include that the number of recorded wake-up signals is not less than a preset number threshold, and the first SOC is the charge state when the battery management system begins to dormant.

[0022] Thirdly, embodiments of this application propose a battery including a battery management system for implementing the method of the first aspect.

[0023] Fourthly, embodiments of this application propose a vehicle that includes the battery of the third aspect.

[0024] Fifthly, embodiments of this application provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the method of the first aspect. Attached Figure Description

[0025] Figure 1 This is a flowchart illustrating a method for determining the state of charge of a battery according to an embodiment of this application.

[0026] Figure 2 This is a schematic diagram illustrating the connection between a battery and a vehicle, as shown in an embodiment of this application.

[0027] Figure 3 This is a flowchart illustrating a method for determining the state of charge of a battery according to another embodiment of this application.

[0028] Figure 4 This is a flowchart illustrating a method for determining the state of charge of a battery according to another embodiment of this application.

[0029] Figure 5 This is a structural block diagram of a battery state of charge determination device according to an embodiment of this application.

[0030] Figure 6 This is a structural diagram of the battery provided in the embodiments of this application. Detailed Implementation

[0031] To make the technical problems, technical solutions, and beneficial effects solved by this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0032] In related technologies, the state of charge (SOC) of a battery can be determined by recording the battery's current dynamics. However, through long-term research, the inventors have found that the determined SOC is not accurate enough in some situations.

[0033] Below are some examples of situations where the determined SOC is not accurate enough.

[0034] Specifically, in some situations, such as before a battery is installed in a vehicle, it may be stored in a warehouse. During this storage phase (i.e., while the battery is in storage), the battery may experience zero-drift current. However, the Battery Management System (BMS) is in a dormant state during this time and does not record this zero-drift current, leading to a distorted State of Charge (SOC). For example, when the BMS is in a dormant state, the battery may experience zero-drift current (e.g., self-discharge during storage), but the BMS does not record this zero-drift current. In other words, the battery's SOC has changed, but the BMS does not detect this change, resulting in an inaccurate SOC determination. In other situations, after the battery is installed in the vehicle, the BMS will also enter a dormant state when the vehicle is powered off. If the tailgate or door is opened (at which time the vehicle may not be powered on, so the BMS is still in a dormant state), the battery needs to provide current to assist in the operation, such as to assist in opening the tailgate or door, or to assist in turning on the lights inside the vehicle. At this time, the battery will have zero drift current. However, the Battery Management System (BMS) is in a dormant state and does not count the zero drift current during this period, which will also lead to SOC distortion.

[0035] Although current BMS improves accuracy through the fusion of multiple algorithms such as ampere-hour integration, open circuit voltage (OCV) calibration, and Kalman filtering, there are still blind spots in special scenarios: for example, milliampere-level zero-drift current in the storage stage can cause significant distortion of SOC.

[0036] Terminology Explanation: Zero-drift current is the core systematic error source of the current sampling system, which directly affects the current measurement accuracy of the battery management system, especially the error accumulation of ampere-hour integration (SOC estimation).

[0037] In view of this, embodiments of this application provide a method for determining the state of charge (SOC) of a battery, a battery, and a vehicle. During the dormant period of the battery management system (BMS), the method detects the battery's current data and a wake-up signal for waking the battery; determines whether a SOC calibration condition is met, including that the number of recorded wake-up signals is not less than a preset threshold; and, in response to meeting the SOC calibration condition, calibrates the battery's first SOC based on the current data to obtain the battery's second SOC. The first SOC is the charge state when the BMS begins its dormant state. This allows for the detection of the time period during which the BMS is in a dormant state. The system uses the battery's current data during the period when the battery management system is in a dormant state to calibrate the first state of charge (SOC) and obtain the second SOC. This is done only when certain conditions for SOC calibration are met (e.g., the number of recorded wake-up signals is not less than a preset threshold). This avoids constant SOC calibration; calibration is only performed when the number of recorded wake-up signals is not less than a preset threshold. This reduces false triggering of SOC updates and improves their accuracy. Furthermore, since the SOC is calibrated using battery current data during the dormant period of the battery management system, the accuracy of the determined SOC is improved.

[0038] The following section provides a detailed explanation of the method for determining the state of charge of a battery.

[0039] Please see Figure 1 , Figure 1 This is a flowchart illustrating a method for determining the state of charge of a battery according to an embodiment of this application. Figure 1 The method shown can be executed by the battery management system in the battery, such as... Figure 1 The methods shown may include: S110. During the sleep period of the battery management system, detect the battery current data and detect the wake-up signal used to wake up the battery.

[0040] S120. Determine whether the state of charge calibration conditions are met. The state of charge calibration conditions include that the number of recorded wake-up signals is not less than a preset threshold number.

[0041] S130. In response to meeting the state of charge calibration conditions, the first state of charge of the battery is calibrated based on the current data to obtain the second state of charge of the battery. The first state of charge is the charge state when the battery management system starts to hibernate.

[0042] The state of charge (SOC) calibration condition can be used to determine whether the battery's SOC needs to be calibrated. In this embodiment, the SOC calibration condition can indicate that the battery has been installed in the vehicle (i.e., installed in the vehicle) or that the vehicle has been fully activated (switching from a power-off state to a power-on state). In other words, the battery's first SOC is calibrated based on current data only after the battery is installed or the vehicle has been fully activated. Specifically, in this embodiment, the preset number of times threshold can be set as needed, for example, set to 5. If the number of recorded activation signals is not less than the preset number of times threshold, it can be considered that the battery has been installed or the vehicle has been fully activated. The battery can include cells and a battery management system, and the battery's SOC can be the cell's SOC. Optionally, the battery in this embodiment can be a 12-volt (V) low-voltage small battery or a high-voltage power battery. Optionally, the battery in this embodiment can be a lithium battery. A 12-volt battery can be the core power source to ensure normal vehicle operation, safety protection, and a comfortable experience. The 12V power supply focuses on low-voltage auxiliary functions, covering all scenarios from startup and control to onboard equipment. A traction battery is a high-power, high-energy-density battery system that provides driving power or core energy storage for new energy vehicles (pure electric / hybrid), construction machinery, energy storage systems, etc. The battery management system (BMS) can include an embedded system comprising a hardware platform (physical carrier) and software algorithms. The hardware provides physical layer data acquisition, instruction execution, and security protection capabilities, while the software implements data processing, state estimation (such as SOC estimation), control strategies, and fault diagnosis, achieving full lifecycle management of the battery. In this embodiment, the battery management system is used to manage the battery, for example, to estimate the battery's SOC. It should be noted that the battery management system in this embodiment can also enter a wake-up state. When the battery management system is in the wake-up state, the frequency at which it detects the battery current is higher than when it is in the sleep state, and the frequency of the signals detected by the battery management system is also higher when it is in the wake-up state. In this embodiment, by detecting the current data during the sleep period of the battery management system, the operating status of the battery when the battery management system is in sleep mode can be determined, and then the battery's SOC can be calibrated using the current data from the battery management system during the sleep period.

[0043] In this embodiment, the second state of charge (SOC) can be determined based on the first SOC and current data during the battery management system's dormant period. The current data in this embodiment can include current values, which can be positive, indicating battery charging (e.g., recharging during battery storage), or negative, indicating battery discharging (e.g., self-discharge during battery storage or power consumption by the vehicle load after battery installation). Optionally, when the sum of the current values ​​in the current data is positive, the second SOC can be greater than the first SOC; when the sum of the current values ​​in the current data is negative, the second SOC can be less than the first SOC.

[0044] In this embodiment, during the sleep period of the battery management system, the battery current data and the wake-up signal for waking up the battery are detected. In response to meeting the state of charge (SOC) calibration conditions, the first SOC of the battery is calibrated based on the current data to obtain the second SOC. The SOC calibration conditions include that the number of recorded wake-up signals is not less than a preset threshold. The first SOC is the charge state when the battery management system begins its sleep period. This allows for the detection of battery current data during the sleep period, and calibration of the first SOC based on the battery current data during the sleep period when the number of recorded wake-up signals is not less than the preset threshold, thus improving the accuracy of the determined SOC. Furthermore, calibrating the SOC only when the number of recorded wake-up signals is not less than the preset threshold reduces false triggering of SOC updates, thereby improving the accuracy of SOC update triggering.

[0045] In one possible implementation, the wake-up signal includes at least one of a tailgate trigger signal and a door trigger signal of the vehicle to which the battery is installed, wherein the tailgate trigger signal is used to indicate that the tailgate is switched from a closed state to an open state, and the door trigger signal is used to indicate that the door is switched from a closed state to an open state.

[0046] In this embodiment, if at least one of the trigger signals from the tailgate and the vehicle door of the vehicle where the battery is installed is detected, and the number of wake-up signals reaches a preset threshold, then the battery can be considered installed, and the battery's SOC calibration is triggered. Optionally, the tailgate trigger signal and the vehicle door trigger signal can be counted separately or cumulatively; this is not limited here. For example, the battery's SOC calibration can be triggered when the cumulative number of the tailgate trigger signal and the vehicle door trigger signal reaches a preset threshold; alternatively, the battery's SOC calibration can be triggered when both the number of tailgate trigger signals and the number of vehicle door trigger signals reach preset thresholds; this is not limited here. In this embodiment, when the tailgate switches from a closed state to an open state, the tailgate trigger signal can be detected; when the vehicle door switches from a closed state to an open state, the vehicle door trigger signal can be detected.

[0047] It should be noted that the trigger signals for the tailgate and the doors in this embodiment can be specific waveform signals or conventional waveform signals (such as waveforms consistent with battery charging signals), and no limitation is imposed here. The trigger signals in this embodiment can be signals triggered by physical switches, such as signals triggered by physical buttons on the tailgate and doors, or signals triggered by communication commands, such as commands sent to the vehicle by an application to open the tailgate or doors, and no limitation is imposed here.

[0048] In this embodiment, the wake-up signal includes at least one of the tailgate trigger signal and the door trigger signal of the vehicle where the battery is installed. The tailgate trigger signal is used to indicate that the tailgate switches from a closed state to an open state, and the door trigger signal is used to indicate that the door switches from a closed state to an open state. In this way, the SOC calibration can be triggered by the trigger signals of the vehicle's tailgate and / or door, thereby enabling a more accurate determination of the SOC calibration of the battery, which is beneficial to improving the use of the battery after it is installed in the vehicle.

[0049] In another possible implementation, other signals can be used as wake-up signals, such as the vehicle power-on signal, which is used to indicate that the vehicle is switching from a power-off state to a power-on state.

[0050] In one possible implementation, the positive and negative terminals of the battery are used to connect to the vehicle's load, the battery's battery management system is used to connect to one end of the tailgate control switch, the other end of the tailgate control switch is grounded, and the tailgate control switch is used to control the tailgate to switch from a closed state to an open state when closed.

[0051] Please see Figure 2 , Figure 2This is a schematic diagram illustrating the connection between a battery 210 and a vehicle, as shown in an embodiment of this application. Figure 2 As shown, the positive and negative terminals of battery 210 are used to connect to the vehicle's load. The battery management system of battery 210 is connected to one end of tailgate control switch S1, and the other end of tailgate control switch S1 is grounded. Tailgate control switch S1 is used to control the tailgate to switch from a closed state to an open state when closed. Therefore, when tailgate control switch S1 is closed, it can control the tailgate to switch from a closed state to an open state, and the battery management system can simultaneously receive a wake-up signal. In this embodiment, the vehicle's load can refer to a load that requires electricity, such as vehicle lights, etc., and is not limited here.

[0052] Accordingly, the method also includes: detecting the tailgate trigger signal through the battery 210 management system of the battery 210, the tailgate trigger signal being a signal sent to the battery 210 when the tailgate control switch S1 is closed.

[0053] It should be noted that the battery 210 was not connected to the vehicle load 220 and the tailgate control switch S1 before it was installed in the vehicle; the vehicle load 220 and the tailgate control switch S1 were connected after it was installed in the vehicle.

[0054] In this embodiment, the positive and negative terminals of the battery are used to connect to the vehicle's load, the battery's battery management system is used to connect to one end of the tailgate control switch, and the other end of the tailgate control switch is grounded. The tailgate control switch is used to control the tailgate to switch from the closed state to the open state when it is closed. In this way, the tailgate trigger signal can be detected by the battery management system, which improves the convenience of detecting the tailgate trigger signal and does not rely on other hardware.

[0055] In another possible implementation, the wake-up signal can also be collected by other controllers and forwarded to the battery management system. For example, controllers such as the Electronic Control Unit (ECU) and Engine Control Module (ECM) can collect the wake-up signal and forward it to the battery management system.

[0056] Optionally, the battery's battery management system is also connected to one end of the door control switch, the other end of which is grounded. The door control switch controls the door to switch from a closed to an open state when closed. Therefore, when the door control switch is closed, it can control the door to switch from a closed to an open state, and the battery management system can simultaneously receive a wake-up signal. Correspondingly, the method also includes detecting a door trigger signal through the battery management system. The door trigger signal is a signal sent to the battery when the door control switch is closed. This allows the battery management system to detect the door trigger signal, improving the convenience of trigger signal detection and eliminating reliance on other hardware.

[0057] In one possible implementation, the method also includes: When a preset signal is detected, the duration of the preset signal is determined. If the duration of the preset signal is greater than the duration threshold, the preset signal is recorded as a wake-up signal. If the duration of the preset signal is not greater than the duration threshold, the preset signal is not recorded.

[0058] In this embodiment, the preset signal can be a signal with a specific waveform, such as a high-level signal or a low-level signal, and there is no limitation on this. The duration of this embodiment can be set as needed, for example, to 500 milliseconds (ms).

[0059] In this embodiment, when a preset signal is detected, the duration of the preset signal is determined. If the duration of the preset signal is greater than the duration threshold, the preset signal is recorded as a wake-up signal. If the duration of the preset signal is not greater than the duration threshold, the preset signal is not recorded. This reduces the possibility of false wake-up signal judgment due to signal jitter, thereby improving the accuracy of wake-up signal recording, which is beneficial for improving the accuracy of SOC determination and reducing the required storage resources.

[0060] Another possible implementation is to disregard the duration of the preset signal, which would reduce the required computing resources.

[0061] In one possible implementation, the method also includes: Determine the detection interval between any two detected wake-up signals; if the detection interval between any two wake-up signals is greater than the time interval threshold, record any two wake-up signals; if the detection interval between any two wake-up signals is not greater than the time interval threshold, record one of the two wake-up signals.

[0062] Specifically, in this embodiment, by determining the magnitude of the detection interval between any two wake-up signals and the time interval threshold, the possibility of false recording of wake-up signals can be reduced. Figure 2 For example, regarding the tailgate, the tailgate control switch can also be used to switch the tailgate from the open state to the closed state. When the tailgate control switch closes again, a wake-up signal will be received. That is to say, the tailgate may receive two wake-up signals when it goes from closed to open and then back to closed. However, the tailgate is essentially only woken up once. Without the judgment based on the detection interval between any two wake-up signals and the time interval threshold in this embodiment, the wake-up signal would be incorrectly recorded. The time interval threshold in this embodiment can be set as needed, for example, 5 minutes (min), and is not limited here.

[0063] In this embodiment, the detection interval between any two detected wake-up signals is determined; if the detection interval between any two wake-up signals is greater than the time interval threshold, then any two wake-up signals are recorded; if the detection interval between any two wake-up signals is not greater than the time interval threshold, then one of the two wake-up signals is recorded. This reduces the possibility of false wake-up signal recording, improves the accuracy of wake-up signal recording, and helps improve the trigger accuracy of SOC calibration.

[0064] Another possible implementation is to record all detected wake-up signals, which can reduce the required computing resources and improve the recording efficiency of wake-up signals.

[0065] In one possible implementation, the method also includes: If the current value in the current data is greater than the current threshold, the current value will be deleted from the current data.

[0066] Specifically, in this embodiment, the self-discharge of the battery or the current value of the vehicle load are generally not particularly large, for example, not exceeding the current threshold. However, during the transportation of the battery or the vehicle equipped with the battery, there may be instances of false current detection due to electromagnetic interference, and in these cases, the current value caused by electromagnetic interference may be relatively large, for example, exceeding the current threshold.

[0067] This embodiment removes abnormal current values ​​from the current data if the current value in the current data is greater than the current threshold, thereby filtering out abnormal current values ​​and improving the accuracy of the determined SOC.

[0068] In another possible implementation, the magnitude of the current value in the current data may not need to be considered, which can reduce the computing resources required to determine the SOC.

[0069] In one possible implementation, the first state of charge is calibrated based on current data to obtain the second state of charge of the battery, including: The change in battery charge during the battery management system's sleep period is determined based on current data. The change in battery state of charge during the sleep period is also determined based on the change in charge, with the change in state of charge being positively correlated with the change in charge. The second state of charge is determined based on the first state of charge and the change in state of charge, with the second state of charge being positively correlated with the first state of charge and negatively correlated with the change in state of charge.

[0070] For example, in this embodiment, the SOC compensation is performed by integrating the ampere-hours according to the formula SOC2 (second state of charge) = SOC1 (first state of charge) - (the change in charge during the dormant period of the battery management system / the nominal capacity at the current temperature).

[0071] In this embodiment, the change in battery charge during the sleep period of the battery management system is determined based on current data; the change in state of charge (SOC) during the sleep period of the battery management system is determined based on the change in battery charge during the sleep period of the battery management system, and the change in SOC is positively correlated with the change in charge; the second SOC of the battery is determined based on the first SOC and the change in SOC, and the second SOC is positively correlated with the first SOC and negatively correlated with the change in SOC, which makes the accuracy of the calibrated second SOC higher.

[0072] In one possible implementation, in response to satisfying the state of charge calibration conditions, the first state of charge of the battery is calibrated based on current data to obtain the second state of charge of the battery, including: When the battery management system is in a wake-up state, in response to meeting the state of charge calibration conditions, it calibrates the first state of charge of the battery based on the current data to obtain the second state of charge of the battery.

[0073] In this example, when the battery management system is in a wake-up state, in response to meeting the state of charge (SOC) calibration conditions, it acquires the battery's first state of charge (SOC) and the battery's current data during the battery management system's sleep period. Based on the battery's current data during the sleep period, the first SOC is calibrated to obtain the second SOC. This means that the battery management system only acquires the first SOC and the battery's current data during the sleep period when it needs to manage the battery based on the SOC. The calibration of the first SOC based on the battery's current data during the sleep period reduces false triggering of SOC calibration and improves the resource utilization of the battery management system.

[0074] In another possible implementation, if the state of charge calibration conditions are met when the battery management system is in a dormant state, the first state of charge of the battery and the current data of the battery during the dormant period of the battery management system can be obtained. The first state of charge can then be calibrated based on the current data of the battery during the dormant period of the battery management system to obtain the second state of charge, which can improve the timeliness of state of charge calibration.

[0075] The solution in this embodiment can be used for zero-drift current processing during the dormant period of storage or battery management systems, improving SOC accuracy, including but not limited to the following scenarios: Storage period: Completely isolate the zero-drift current integration path to improve SOC calculation accuracy; During the vehicle loading transition period: the tailgate will be activated after 5 activations to prevent accidental triggering; Service life: Static current compensation mechanism improves accuracy.

[0076] For ease of understanding, the following examples are illustrated in conjunction with the examples above.

[0077] Please see Figure 3 , Figure 3 This is a flowchart illustrating a method for determining the state of charge of a battery according to another embodiment of this application. Figure 3 The method shown can be executed by the battery management system in the battery, such as... Figure 3 The methods shown may include: S310, the battery management system enters sleep mode.

[0078] S320: If the battery management system in sleep mode detects a preset signal, it determines the duration of the preset signal.

[0079] S330. If the duration of the preset signal is greater than the duration threshold, the battery management system in sleep mode will record the preset signal as a wake-up signal. If the duration of the preset signal is not greater than the duration threshold, the battery management system in sleep mode will not record the preset signal.

[0080] S340, The battery management system in sleep mode determines the detection interval between any two detected wake-up signals.

[0081] S350. If the detection interval between any two wake-up signals is greater than the time interval threshold, the battery management system in sleep mode records any two wake-up signals. If the detection interval between any two wake-up signals is not greater than the time interval threshold, the battery management system in sleep mode records one of the two wake-up signals.

[0082] The S360's battery management system, in sleep mode, monitors the battery's current data.

[0083] S370, Battery Management System enters wake-up state.

[0084] S380. If the current value in the current data is greater than the current threshold, the battery management system in the wake-up state will delete the current value from the current data.

[0085] S390. The battery management system in the wake-up state determines whether the state of charge calibration conditions are met. The state of charge calibration conditions include that the number of recorded wake-up signals is not less than a preset number threshold.

[0086] S400, the battery management system in the wake-up state responds to the condition of satisfying the state of charge calibration by calibrating the first state of charge of the battery based on the current data to obtain the second state of charge of the battery. The first state of charge is the charge state when the battery management system starts to sleep.

[0087] This embodiment can be referred to the description of the above embodiment, and will not be repeated here.

[0088] It should be understood that the order of the steps in the above embodiments can be set as needed and is not limited here.

[0089] For ease of understanding, the following example uses tailgate triggering as an example to illustrate the calibration of SOC.

[0090] Please see Figure 4 , Figure 4 This is a flowchart illustrating a method for determining the state of charge of a battery according to another embodiment of this application. Figure 4 The method shown can be executed by the battery management system, such as Figure 4 The methods may include: S410, Wake up.

[0091] S420: Read the tailgate count and the cumulative capacity in hibernation mode.

[0092] In this embodiment, the tailgate count read can be the count of tailgate trigger signals. The cumulative capacity in the sleep state can be determined based on current data, and the cumulative capacity represents the change in battery capacity.

[0093] S430: Determine if the tailgate signal duration is greater than 500ms.

[0094] The 500ms value can be found in the description of the duration threshold.

[0095] S440, tailgate counter +1.

[0096] S450, Determine if the tailgate count is greater than 5.

[0097] Among them, 5 can be referred to the description of the preset number of times threshold.

[0098] S460, SOC2 = SOC1 - (cumulative capacity in dormancy / nominal capacity at current temperature).

[0099] Wherein, SOC1 can be referred to the description of the first state of charge, and SOC2 can be referred to the description of the second state of charge.

[0100] S470, SOC2 = SOC1.

[0101] In this step, the capacity in the sleep state is not calculated, and the zero drift current is ignored.

[0102] S480, Determine whether the hibernation conditions are met.

[0103] In this embodiment, the sleep conditions may include the battery current being less than a preset current and the duration of no wake-up signal exceeding a wake-up time threshold (e.g., 5 seconds).

[0104] S490, store tailgate counter, enter hibernation, and perform static current statistics in hibernation.

[0105] In this embodiment, current data can be obtained by performing static current statistics.

[0106] In summary, this embodiment may include steps one through five.

[0107] Step 1: Monitor and store the current value in sleep mode in real time. Step 2: Accumulate and store the number of valid tailgate triggers. Step 3: Determine the number of valid tailgate triggers in real time. Step 4: Enable / disable sleep current statistics based on the number of tailgate triggers. Step 5: Once the tailgate trigger count is reached, the function is enabled, and the stored static current value is accumulated by integrating the ampere-hours.

[0108] Step 1: Monitor and store the current value during sleep mode in real time. Hibernation criteria: Current <1A for 5 seconds without wake-up signal; Current monitoring during hibernation is stored in non-volatile memory. Parameter: The storage capacity of the non-volatile memory is sufficient for recording data during hibernation. Step 2: Count and store the valid counts triggered by the tailgate: Tailgate wake-up signal is valid: duration is at least 500ms to prevent false signals; Valid count storage: The stored count is at least greater than 10.

[0109] Step 3: Real-time determination of wake-up count: Timing of judgment: Real-time detection; Counting rule: The interval between each count must be at least 5 minutes to prevent duplicate counting; Step 4: Start and stop the hibernation statistics function: Activation conditions: The tailgate signal has been valid ≥ 5 times; Prohibited condition: The tailgate signal has been valid ≤ 5 times.

[0110] Step 5: Static current compensation integration: Compensation for the current integral in the sleep state, parameter: SOC2 = SOC1 - capacity in sleep state / nominal capacity.

[0111] In other words, during the sleep monitoring phase, when the system detects a current <1A for 5 seconds without a wake-up signal, it enters sleep mode. After waking up, if the tailgate count is <5, the current data is discarded (zero drift current during storage is completely isolated). A tailgate trigger lasting ≥500ms with a time interval greater than 5 minutes between two consecutive valid triggers is considered valid, and the tailgate count is incremented by one. If the tailgate count is ≥5, SOC compensation is performed using ampere-hour integration calculated according to the formula SOC = SOC - (sleep capacity / nominal capacity at current temperature). This embodiment addresses the issue of zero drift current during battery storage sleep, eliminating its impact on SOC during storage. After the battery is put into actual use, the tailgate trigger mechanism activates the monitoring of the vehicle's static current, eliminating the problem of artificially reduced SOC during storage and filling the gap in SOC calculation technology for special scenarios.

[0112] This embodiment constructs the SOC calculation for the entire battery lifecycle based on the number of effective tailgate triggers. Dormant current is calculated only after the confirmed usage phase (count ≥ 5), avoiding SOC errors caused by zero-drift current during storage. Reliability is further enhanced through a triple mechanism of 500ms tailgate signal filtering and a 5-minute counting interval. This solution creatively improves SOC accuracy and increases fault suppression rate by 90% during vehicle installation.

[0113] As a result, SOC accuracy can be significantly improved: SOC error during storage is reduced, and the incidence of SOC error problems in the early stages of vehicle installation is reduced; moreover, with zero-cost hardware modifications, the problem of falsely reduced SOC during battery storage is solved, raising the industry's technical and economic boundaries; in addition, the tailgate hardware signal triggering mechanism can avoid false triggering and undetected issues.

[0114] Specifically, this embodiment discloses a battery storage period SOC calibration method and processing approach to solve the problem of accumulated ampere-hour integration error caused by zero drift in current sampling. During the dormant period of the BMS battery management system, current data is continuously collected at a specific frequency and stored in non-volatile memory; vehicle tailgate opening events are counted, and when the cumulative number reaches a preset threshold (N < 5), the current data (zero drift current) stored during the dormant period is discarded; (N ≥ 5), the current data stored during the dormant period is statistically analyzed to improve current accuracy. This specifically involves an optimization technique for battery state of charge (SOC) estimation methods in long-term storage scenarios, applicable to battery management systems that require precise management of minute currents during the dormant period.

[0115] Please see Figure 5 , Figure 5 This is a structural block diagram of a battery state of charge determination device according to an embodiment of this application. Figure 5 The device can be applied to battery management systems, such as Figure 5 The device may include a detection module 510 and a calibration module 520, wherein: The detection module 510 is used to detect the current data of the battery and the wake-up signal for waking up the battery during the hibernation period of the battery management system; the calibration module 520 is used to calibrate the first state of charge of the battery based on the current data in response to meeting the state of charge calibration conditions, so as to obtain the second state of charge of the battery. The state of charge calibration conditions include that the number of recorded wake-up signals is not less than a preset number threshold, and the first state of charge is the charge state when the battery management system starts to hibernate.

[0116] In one possible implementation, the wake-up signal includes at least one of a tailgate trigger signal and a door trigger signal of the vehicle to which the battery is installed, wherein the tailgate trigger signal is used to indicate that the tailgate is switched from a closed state to an open state, and the door trigger signal is used to indicate that the door is switched from a closed state to an open state.

[0117] In one possible implementation, the positive and negative terminals of the battery are used to connect to the vehicle's load, the battery's battery management system is used to connect to one end of the tailgate control switch, the other end of the tailgate control switch is grounded, and the tailgate control switch is used to control the tailgate to switch from a closed state to an open state when closed; the detection module 510 is also used to: detect the tailgate trigger signal through the battery's battery management system, the tailgate trigger signal being a signal sent to the battery when the tailgate control switch is closed.

[0118] In one possible implementation, the detection module 510 is further configured to: when a preset signal is detected, determine the duration of the preset signal; if the duration of the preset signal is greater than a duration threshold, record the preset signal as a wake-up signal; if the duration of the preset signal is not greater than the duration threshold, do not record the preset signal.

[0119] In one possible implementation, the detection module 510 is further configured to: determine the detection interval between any two detected wake-up signals; if the detection interval between any two wake-up signals is greater than the time interval threshold, then record any two wake-up signals; if the detection interval between any two wake-up signals is not greater than the time interval threshold, then record one of the two wake-up signals.

[0120] In one possible implementation, the detection module 510 is further configured to: delete the current value from the current data if the current value in the current data is greater than the current threshold.

[0121] In one possible implementation, when the calibration module 520 calibrates the first state of charge based on current data to obtain the second state of charge of the battery, it is used to: determine the change in charge of the battery during the dormant period of the battery management system based on the current data; determine the change in state of charge of the battery during the dormant period of the battery management system based on the change in charge of the battery during the dormant period of the battery management system, wherein the change in state of charge is positively correlated with the change in charge; and determine the second state of charge of the battery based on the first state of charge and the change in state of charge, wherein the second state of charge is positively correlated with the first state of charge and negatively correlated with the change in state of charge.

[0122] In one possible implementation, when the calibration module 520 calibrates the first state of charge of the battery based on current data in response to meeting the state of charge calibration conditions to obtain the second state of charge of the battery, it is configured to: when the battery management system is in a wake-up state, calibrate the first state of charge of the battery based on current data in response to meeting the state of charge calibration conditions to obtain the second state of charge of the battery.

[0123] The apparatus in this embodiment can be referred to the description of the method above, and will not be repeated here.

[0124] This application also provides a battery, please refer to... Figure 6 , Figure 6 The battery 600 shown includes a battery management system 610. The battery management system includes a processor 611 and a memory 612, wherein the memory 611 is used to store computer programs; and the processor 612 is used to execute the programs stored in the memory 611 to implement the methods described in any embodiment of this application.

[0125] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the method described in any embodiment of this application.

[0126] In this application, "multiple" refers to two or more.

[0127] In this application, unless otherwise expressly defined, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0128] The terms “first,” “second,” “third,” “fourth,” etc., in this application (if present) are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0129] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0130] Unless otherwise specified, all steps in this application may be performed sequentially or randomly. For example, if a method includes steps A and B, it means that the method may include steps A and B performed sequentially, or it may include steps B and A performed sequentially. For example, if a method may also include step C, it means that step C may be added to the method in any order. For example, the method may include steps A, B, and C, or it may include steps A, C, and B, or it may include steps C, A, and B, etc.

[0131] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for determining the state of charge of a battery, characterized in that, include: During the sleep period of the battery management system, the battery current data is detected and a wake-up signal for waking up the battery is detected; Determine whether the state of charge calibration conditions are met, wherein the state of charge calibration conditions include that the number of recorded wake-up signals is not less than a preset number threshold. In response to meeting the state of charge calibration conditions, the first state of charge of the battery is calibrated based on the current data to obtain the second state of charge of the battery. The first state of charge is the charge state when the battery management system begins to hibernate.

2. The method according to claim 1, characterized in that, The wake-up signal includes at least one of a tailgate trigger signal and a door trigger signal of the vehicle to which the battery is installed. The tailgate trigger signal is used to indicate that the tailgate switches from a closed state to an open state, and the door trigger signal is used to indicate that the door switches from a closed state to an open state.

3. The method according to claim 2, characterized in that, The positive and negative terminals of the battery are used to connect to the load of the vehicle. The battery management system of the battery is used to connect to one end of the tailgate control switch. The other end of the tailgate control switch is grounded. The tailgate control switch is used to control the tailgate to switch from the closed state to the open state when it is closed. The method further includes: The battery management system of the battery detects the trigger signal of the tailgate, which is a signal sent to the battery when the tailgate control switch is closed.

4. The method according to claim 1, characterized in that, The method further includes: When a preset signal is detected, the duration of the preset signal is determined; If the duration of the preset signal is greater than the duration threshold, the preset signal will be recorded as a wake-up signal. If the duration of the preset signal is not greater than the duration threshold, then the preset signal is not recorded.

5. The method according to claim 1, characterized in that, The method further includes: Determine the detection interval between any two detected wake-up signals; If the detection interval between any two wake-up signals is greater than the time interval threshold, then record any two wake-up signals. If the detection interval between any two wake-up signals is not greater than the time interval threshold, then one of the two wake-up signals is recorded.

6. The method according to claim 1, characterized in that, The method further includes: If the current value in the current data is greater than the current threshold, then the current value is deleted from the current data.

7. The method according to any one of claims 1-6, characterized in that, The step of calibrating the first state of charge based on the current data to obtain the second state of charge of the battery includes: The change in battery charge during the dormant period of the battery management system is determined based on the current data; Based on the change in charge of the battery during the dormancy period of the battery management system, the change in state of charge of the battery during the dormancy period of the battery management system is determined, and the change in state of charge is positively correlated with the change in charge. Based on the first state of charge and the change in state of charge, a second state of charge of the battery is determined. The second state of charge is positively correlated with the first state of charge and negatively correlated with the change in state of charge.

8. The method according to claim 1, characterized in that, The method is executed by the battery management system, wherein, in response to meeting the state of charge calibration conditions, the first state of charge of the battery is calibrated based on the current data to obtain the second state of charge of the battery, including: When the battery management system is in a wake-up state, in response to meeting the state of charge calibration conditions, the first state of charge of the battery is calibrated based on the current data to obtain the second state of charge of the battery.

9. A battery, characterized in that, Includes a battery management system, said battery management system being used to implement the method of any one of claims 1-8.

10. A vehicle, characterized in that, It includes the battery as described in claim 9.

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