Estimation method, device and equipment of state of charge of battery and storage medium

Abstract

The invention provides a battery state-of-charge estimation method and device, equipment and a storage medium. The method comprises the steps that the duration of low-voltage power-on of a battery is acquired; when the duration time is greater than a preset standing time, screening out the maximum voltage from the voltages of all the single cells; determining whether the screened voltage is greater than a preset battery steady-state voltage; if the screened voltage is greater than the preset battery steady-state voltage, determining a first charge state of the battery based on the power consumption of all the single cells; and if the screened voltage is not greater than the preset battery steady-state voltage, determining a second state of charge of the battery based on a mapping relationship between the open-circuit voltage of the single cell and the state of charge of the single cell. By adopting the technical scheme provided by the invention, the charge state estimation accuracy of the battery during low-voltage power-on is improved.

Description

TECHNICAL FIELD

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

[0002] With the wide application of lithium-ion power battery in electric vehicles, accurately estimating the state of charge (SOC) of the battery is particularly important for the battery management system (BMS). This estimation not only ensures that the battery is used correctly, but also helps to optimize the charging and discharging strategy, improve energy utilization efficiency, and enhance user experience, so that users can plan their journey based on accurate SOC information. At present, the SOC estimation of most electric vehicle power batteries mainly adopts the ampere-hour integration method.

[0003] However, when the vehicle is in the display mode, some vehicles may use an external storage battery, at this time the power battery is not connected to the high-voltage system, and the BMS usually supplies power by directly taking power from the power battery module. In addition to the energy consumption during battery balancing, the actual power of the power battery will gradually decrease. The battery power calculated by the ampere-hour integration method is in a constant state, which leads to a large error in the SOC estimated by the ampere-hour integration method when the actual power of the power battery changes. SUMMARY

[0004] Therefore, the embodiments of the present application provide a battery state of charge estimation method, device, equipment and storage medium, which improves the accuracy of the state of charge estimation of the battery when it is powered on at low voltage.

[0005] The present application mainly includes the following aspects: In a first aspect, the embodiments of the present application provide a battery state of charge estimation method, the battery comprising at least one single cell; the estimation method comprising: obtaining the duration of the low-voltage power-on of the battery; when the duration is greater than a preset resting time, selecting the maximum voltage from the voltages of all single cells; determining whether the selected voltage is greater than a preset battery steady-state voltage; if the selected voltage is greater than the preset battery steady-state voltage, determining a first state of charge of the battery based on the power consumption of all single cells; if the selected voltage is not greater than the preset battery steady-state voltage, determining a second state of charge of the battery based on the mapping relationship between the open-circuit voltage of the single cell and the state of charge of the single cell; Further, the determination of the first state of charge of the battery based on the power consumption of all single cells comprises: determining the first power consumption of an analog front end for collecting and processing battery data based on a preset unit power consumption current; For each single battery cell, determine whether the single battery cell is in an equalization mode for balancing the battery voltage; If the single battery cell is in the equalization mode, determine a second power consumption of the single battery cell when the single battery cell is in the equalization mode; determine the first power consumption as the power consumption of the single battery cell based on the first power consumption, the second power consumption and the power consumption of the single battery cell; If the single battery cell is not in the equalization mode, determine the first power consumption as the power consumption of the single battery cell; Determine a unit state of charge of the single battery cell based on the power consumption and an initial state of charge; Determine a first state of charge of the battery based on an average of the unit state of charge of all single battery cells.

[0006] Further, after the determining the first state of charge of the battery based on the power consumption of all single battery cells when the screened voltage is greater than the preset battery steady-state voltage, the estimation method further comprises: When the highest voltage of the battery cell exceeds the preset battery steady-state voltage, determine a third state of charge of the battery based on a mapping relationship between the open circuit voltage of the single battery cell and the state of charge of the single battery cell; Determine a transition distance of the battery based on a difference between the first state of charge and the third state of charge; Determine a fourth state of charge of the battery based on the transition distance.

[0007] Further, the determining the fourth state of charge of the battery based on the transition distance comprises: Determine whether the transition distance is in a preset difference value interval; If the transition distance is in the preset difference value interval, determine a gain coefficient corresponding to the transition distance; determine a fluctuation state of charge of the battery based on the first state of charge, the third state of charge and the gain coefficient; If the transition distance is not in the preset difference value interval, determine the third state of charge as the fluctuation state of charge of the battery; Filter the fluctuation state of charge to obtain a filtered fluctuation state of charge; Determine the filtered fluctuation state of charge and a minimum value in historical fourth state of charge as the fourth state of charge of the battery; wherein the historical fourth state of charge is the fourth state of charge at a time point before a current time point.

[0008] In a second aspect, the embodiments of the present application further provide a battery state of charge estimation device, the battery comprising at least one single battery cell; the estimation device comprising: An acquisition module configured to acquire a duration of a low-voltage power-on of the battery; A screening module is used to select the highest voltage from all individual cells when the duration is greater than a preset resting time. The judgment module is used to determine whether the filtered voltage is greater than the preset battery steady-state voltage. The first determining module is used to determine the first state of charge of the battery based on the power consumption of all individual cells if the selected voltage is greater than the preset steady-state voltage of the battery. The second determining module is used to determine the second state of charge of the battery based on the mapping relationship between the open circuit voltage of the individual cell and the state of charge of the individual cell if the filtered voltage is not greater than the preset steady-state voltage of the battery.

[0009] Furthermore, the first determining module is specifically used for: Based on the preset unit power consumption current, the first power consumption of the analog front end used for collecting and processing battery data is determined. For each individual cell, determine whether the equalization mode for balancing battery voltage is enabled. If the single cell is in equalization mode, then the second power consumption of the single cell when the equalization mode is activated is determined; the first power consumption and the second power consumption are summed to determine the power consumption of the single cell. If the equalization mode is not enabled for the single cell, the first power consumption is determined as the power consumption of the single cell. Based on the power consumption and initial state of charge, the unit state of charge of the individual battery cell is determined; The first state of charge of the battery is determined by averaging the unit state of charge of all individual cells.

[0010] Furthermore, the estimation device also includes: The third determination module is used to determine the third state of charge of the battery based on the mapping relationship between the open circuit voltage of the battery cell and the state of charge of the battery cell when the highest voltage of the battery cell exceeds the preset steady-state voltage of the battery. The difference module is used to determine the difference between the first state of charge and the third state of charge as the transition distance of the battery. The fourth determining module is used to determine the fourth state of charge of the battery based on the transition distance.

[0011] Furthermore, the fourth determining module is specifically used for: Determine whether the transition distance is within a preset difference range; If the transition distance is within a preset difference range, then the gain coefficient corresponding to the transition distance is determined; based on the first state of charge, the third state of charge, and the gain coefficient, the fluctuating state of charge of the battery is determined; If the transition distance is not within the preset difference range, then the third state of charge is determined as the fluctuating state of charge of the battery. The fluctuating state of charge is filtered to obtain the filtered fluctuating state of charge. The minimum value between the filtered fluctuating state of charge and the historical fourth state of charge is determined as the fourth state of charge of the battery; wherein, the historical fourth state of charge is the fourth state of charge of the previous moment of the current moment.

[0012] Thirdly, embodiments of this application also provide an electronic device, including: a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor communicates with the memory through the bus, and the machine-readable instructions are executed by the processor to perform the steps of the battery state of charge estimation method described in the first aspect or any possible implementation of the first aspect.

[0013] Fourthly, embodiments of this application also provide a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the battery state-of-charge estimation method described in the first aspect or any possible implementation of the first aspect.

[0014] This application provides a method, apparatus, device, and storage medium for estimating the state of charge (SOC) of a battery. The method involves obtaining the duration of low-voltage power-on of the battery; when the duration exceeds a preset resting time, selecting the highest voltage from all individual cell voltages; determining whether the selected voltage exceeds a preset steady-state battery voltage; if the selected voltage exceeds the preset steady-state battery voltage, determining the first SOC of the battery based on the power consumption of all individual cells; if the selected voltage does not exceed the preset steady-state battery voltage, determining the second SOC of the battery based on the mapping relationship between the open-circuit voltage and the SOC of individual cells.

[0015] This improves the accuracy of state-of-charge estimation when the battery is powered on at low voltage.

[0016] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 One of the flowcharts for a method for estimating the state of charge of a battery according to an embodiment of this application is shown; Figure 2 This illustration shows a schematic diagram of the inflection point of an OCV-SOC curve provided in an embodiment of this application; Figure 3 A second flowchart of a method for estimating the state of charge of a battery, as provided in an embodiment of this application, is shown. Figure 4 The third flowchart illustrates a method for estimating the state of charge of a battery according to an embodiment of this application; Figure 5 A flowchart of a method for estimating the state of charge of a battery according to an embodiment of this application is shown in Part IV. Figure 6 The fifth flowchart illustrates a method for estimating the state of charge of a battery according to an embodiment of this application. Figure 7 This illustration shows one of the structural schematic diagrams of a battery state of charge estimation device provided in an embodiment of this application; Figure 8 This is a second schematic diagram of the structure of a battery state of charge estimation device provided in an embodiment of this application; Figure 9 A schematic diagram of the structure of an electronic device provided in an embodiment of this application is shown. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.

[0020] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0021] The methods, apparatus, electronic devices, or computer-readable storage media described in this application can be applied to any scenario requiring TTT. This application does not limit specific application scenarios. Any scheme using the battery state of charge estimation method and apparatus provided in this application is within the protection scope of this application.

[0022] It is worth noting that with the widespread application of lithium-ion batteries in electric vehicles, accurately estimating the battery's state of charge (SOC) is particularly important for the battery management system (BMS). This estimation not only ensures the battery is used correctly but also helps optimize charging and discharging strategies, improve energy efficiency, and enhance the user experience, allowing users to plan their trips based on accurate SOC information. Currently, most electric vehicles primarily use the ampere-hour integral method to estimate the SOC of their power batteries. However, when the vehicle is in demonstration mode, some vehicles may use an external battery. In this case, the power battery is not connected to the high-voltage system, and the BMS typically draws power directly from the power battery module. Combined with energy consumption during battery equalization, the actual battery capacity gradually decreases. The battery capacity calculated using the ampere-hour integral method remains constant, which can lead to significant errors in the SOC estimated using this method when the actual battery capacity changes.

[0023] To address the aforementioned issues, this application provides a method, apparatus, device, and storage medium for estimating the state of charge (SOC) of a battery, thereby improving the accuracy of SOC estimation when the battery is powered on at low voltage.

[0024] To facilitate understanding of this application, the technical solutions provided in this application will be described in detail below with reference to specific embodiments.

[0025] In this embodiment, for battery cells in electric vehicles, especially small-capacity cells used in hybrid electric vehicles (HEVs), the error introduced by long-term discharge is not negligible. If the state of charge (SOC) estimation error is too high, it increases the risk of the vehicle breaking down during subsequent discharge conditions; if the SOC estimation is too low, it will shorten the user's actual driving range. During charging, if the SOC estimation is too high, the user may have to wait too long for a full charge; if the SOC estimation is too low, the SOC will increase too quickly during full charge, affecting the user experience.

[0026] Please see Figure 1 , Figure 1 This is one of the flowcharts for a method of estimating the state of charge of a battery provided in an embodiment of this application.

[0027] like Figure 1 As shown in the embodiments of this application, the method for estimating the state of charge of a battery includes the following steps: Step S101: Obtain the duration of low-voltage power-on of the battery.

[0028] Here, the battery comprises at least one individual cell. When both the main positive relay and the main negative relay are in state zero, the battery is powered on at low voltage and a timer begins, confirming that the battery is in the correction phase of a no-current scenario. When either the main positive relay or the main negative relay transitions to state 1, the battery is connected to high-voltage power. The main positive relay is located between the battery's positive terminal and the high-voltage system's positive busbar, controlling the on / off state of the high-voltage positive circuit; the main negative relay is located between the battery pack's negative terminal and the high-voltage system's negative busbar, controlling the on / off state of the high-voltage negative circuit.

[0029] Step S102: When the duration is greater than the preset resting time, select the highest voltage from all individual cell voltages.

[0030] Here, the preset resting time is the time required for the battery polarization voltage to completely dissipate. When the duration exceeds the preset resting time, the battery is determined to be in discharge mode.

[0031] Step S103: Determine whether the filtered voltage is greater than the preset battery steady-state voltage.

[0032] Here, the battery steady-state voltage is presumably defined as the open-circuit voltage corresponding to the inflection point of the OCV-SOC (open-circuit voltage - state of charge) curve; that is, the inflection point is the initial point at which the voltage gradually stabilizes when the battery is at rest. As an example, such as... Figure 2 As shown, the open-circuit voltage corresponding to the inflection point is 3.265V, which means the preset steady-state battery voltage is 3.265V.

[0033] Step S104: If the selected voltage is greater than the preset steady-state voltage of the battery, then the first state of charge of the battery is determined based on the power consumption of all individual cells.

[0034] Here, as Figure 3 As shown, when the filtered voltage is greater than the preset battery steady-state voltage, the battery is determined to be in the first stage, and the calculation strategy for the first stage is executed. Step S104 is the method for estimating the state of charge of the battery in the first stage.

[0035] The following is combined with Figure 4 This section will explain in detail how to determine the first state of charge of a battery based on the power consumption of all individual cells.

[0036] Please see Figure 4 , Figure 4 This is the third flowchart of a method for estimating the state of charge of a battery provided in an embodiment of this application.

[0037] like Figure 4 As shown, regarding step S104, in a specific implementation, as an example, the following steps may be included: Step S1041: Based on the preset unit power consumption current, determine the first power consumption of the analog front-end used for collecting and processing battery data.

[0038] Here, the preset unit power consumption current is the unit power consumption current of the simulated front-end AFE, which is a key interface circuit used to collect and process battery data. As an example, the preset unit power consumption current is 9mA. As an example, the first power consumption can be calculated using formula (1).

[0039] (1).

[0040] in, The first power consumption, To preset the unit power consumption current, The duration of low-voltage battery charging.

[0041] Step S1042: For each individual cell, determine whether the equalization mode for balancing battery voltage is enabled.

[0042] Here, balancing mode is a technique used in the battery management system (BMS) to ensure that the voltage levels of all individual cells in the battery remain consistent. To determine whether a particular cell has its balancing mode activated to balance the battery voltage, an array of flags containing the balancing status of all individual cells is required. Each element in the array represents the balancing status of a single cell, and its value indicates whether the balancing mode for that cell is activated.

[0043] Step S1043: If the single cell is in balancing mode, then determine the second power consumption when the single cell is in balancing mode.

[0044] When the balancing mode of a single cell is activated, the balancing current value of the single cell is recorded. The balancing current is a real-time calculated value, taking into account the balancing of odd and even cell numbers, the balancing resistance of the balancing cell, and the balancing efficiency of the balancing cell. Once the balancing mode is turned off, the accumulated balancing power consumption of the single cell is retained, which is the second power consumption. As an example, the second power consumption can be calculated using formula (2).

[0045] (2).

[0046] in, This is the second highest power consumption. This represents the balanced current value of a single battery cell.

[0047] Step S1044: The sum of the first power consumption and the second power consumption is determined as the power consumption of the single cell.

[0048] Here, as an example, the power consumption of a single battery cell .

[0049] Step S1045: If the equalization mode is not enabled for the single cell, the first power consumption is determined as the power consumption of the single cell.

[0050] Step S1046: Based on the power consumption and initial state of charge, determine the unit state of charge of the single cell.

[0051] Here, the initial state of charge is the state of charge when the battery starts to be powered on at low voltage. As an example, the unit state of charge of a single cell can be calculated using formula (3).

[0052] (3).

[0053] in, Let i be the unit state of charge of the i-th individual cell. Let i be the initial state of charge of the i-th individual cell. Let be the total capacity of the i-th individual cell.

[0054] Step S1047: The average value of the unit state of charge of all individual cells is used to determine the first state of charge of the battery.

[0055] Here, the first state of charge of the battery refers to the real-time state of charge of the battery in the first stage.

[0056] See again Figure 1In step S105, if the filtered voltage is not greater than the preset steady-state voltage of the battery, the second state of charge of the battery is determined based on the mapping relationship between the open-circuit voltage of the individual cell and the state of charge of the individual cell.

[0057] Here, as Figure 3 As shown, when the filtered voltage is not greater than the preset steady-state voltage of the battery, the battery is determined to be in the second stage, and the calculation strategy of the second stage is executed. Specifically, this step involves correcting the state of charge of each individual cell based on the pre-set mapping relationship between the open-circuit voltage and the state of charge of the individual cell, and determining the average value of the corrected state of charge of all individual cells as the second state of charge of the battery. Step S105 is the method for estimating the state of charge of the battery in the second stage. As an example, the correspondence between the open-circuit voltage and the state of charge of the individual cell is shown in Table 1.

[0058] Table 1. Offline measured OCV-SOC table

[0059] In one possible implementation, such as Figure 5 As shown, after step S104, the estimation method further includes: Step S201: When the highest voltage of a single battery cell exceeds the preset steady-state voltage of the battery, the third state of charge of the battery is determined based on the mapping relationship between the open-circuit voltage of the single battery cell and the state of charge of the single battery cell.

[0060] Here, as Figure 3 As shown, when the battery is in the first stage, the voltage gradually decreases. When the highest voltage of a single battery cell drops to the preset steady-state voltage, the battery transitions from the first stage to the second stage, executing a stage switching fusion strategy to avoid jumps or increases in the state of charge during the switching process. When the battery transitions from the first stage to the second stage, the current state of charge, i.e., the third state of charge, is determined according to the estimation method in step S105.

[0061] Step S202: The difference between the first state of charge and the third state of charge is determined as the transition distance of the battery.

[0062] Here, the transition distance ,in, For transition distance, The first state of charge, This is the third state of charge. This step calculates the difference between the first and second state of charge.

[0063] Step S203: Based on the transition distance, determine the fourth state of charge of the battery.

[0064] The following is combined withFigure 6 This section will explain in detail how to determine the first state of charge of a battery based on the power consumption of all individual cells.

[0065] Please see Figure 6 , Figure 6 This is the fifth flowchart of a method for estimating the state of charge of a battery provided in an embodiment of this application.

[0066] like Figure 6 As shown, regarding step S203, in a specific implementation, as an example, the following steps may be included: Step S2031: Determine whether the transition distance is within a preset difference range.

[0067] Here, as an example, the preset difference range is... Greater than 0.1 Less than 0.

[0068] Step S2032: If the transition distance is within a preset difference range, then determine the gain coefficient corresponding to the transition distance.

[0069] Here, the gain coefficient There is a mapping relationship between the transition distance and the gain coefficient, which is determined by looking up a table. .

[0070] Step S2033: Determine the fluctuating state of charge of the battery based on the first state of charge, the third state of charge, and the gain coefficient.

[0071] Here, the first state of charge and the third state of charge are fused to obtain the fluctuating state of charge of the battery. As an example, the fluctuating state of charge of the battery can be obtained by formula (4).

[0072] (4).

[0073] in, It is in a fluctuating charge state.

[0074] Step S2034: If the transition distance is not within the preset difference range, then the third state of charge is determined as the fluctuating state of charge of the battery.

[0075] Here, when the transition distance is not within the preset difference range, that is, when the transition distance is within the range of [0,0.1], it indicates that the difference between the first charge state and the third charge state is small, so fusion is not required.

[0076] Step S2035: Filter the fluctuating state of charge to obtain the filtered fluctuating state of charge.

[0077] Here, when entering the second stage, the estimation relies entirely on the sampling of the individual cell voltage. Since the individual cell voltage may fluctuate, it may cause the SOC estimation to increase or change slightly. This application uses low-pass filtering to reduce the impact of such fluctuations, which can be achieved through formula (5).

[0078] (5).

[0079] in, This is the filter coefficient, which can be set to 0.1; The filtered fluctuating charge state is...

[0080] Step S2036: The minimum value between the filtered fluctuating state of charge and the historical fourth state of charge is determined as the fourth state of charge of the battery.

[0081] Here, the historical fourth state of charge is the fourth state of charge of the previous time step. To achieve redundancy protection for the fused state of charge and to avoid abnormal increases in the output state of charge due to inconsistencies in the state of charge decreases calculated in the first and second stages, the following approach is adopted: In the current low-voltage power-on scenario, ensure that the current state of charge value does not exceed the smaller value between the calculated state of charge and the previously calculated state of charge. As an example, the fourth state of charge can be obtained through formula (6).

[0082] (6).

[0083] in, This is the fourth state of charge of the battery. This is the fourth charged state at the previous moment.

[0084] The proposed SOC estimation method for power batteries effectively solves the following problems: First, it overcomes the limitation of the ampere-hour integration method in failing to perform SOC calculations under certain conditions; second, it solves the problem of difficulty in calibrating the SOC of lithium iron phosphate batteries using terminal voltage in the voltage plateau region, meaning that it can accurately estimate the SOC even when both terminal voltage and current information are unavailable, significantly improving the SOC accuracy in this scenario. Furthermore, this application is also applicable to ternary lithium-ion batteries.

[0085] This application provides a method for estimating the state of charge of a battery, which improves the accuracy of estimating the state of charge of a battery when it is powered on at low voltage.

[0086] Based on the same application concept, this application also provides a battery state of charge estimation device corresponding to the battery state of charge estimation method provided in the above embodiments. Since the principle of the device in this application is similar to the battery state of charge estimation method in the above embodiments of this application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be described again.

[0087] Please see Figures 7 to 8 , Figure 7 This is one of the structural schematic diagrams of a battery state of charge estimation device provided in an embodiment of this application. Figure 8 This is a second schematic diagram of a battery state of charge estimation device provided in an embodiment of this application.

[0088] like Figure 7 As shown in the illustration, the battery state of charge estimation device 710 provided in this application embodiment includes: The acquisition module 711 is used to acquire the duration of the battery being powered on at low voltage. The screening module 712 is used to screen out the highest voltage from all individual cells when the duration is greater than a preset resting time. The judgment module 713 is used to determine whether the filtered voltage is greater than the preset battery steady-state voltage. The first determining module 714 is used to determine the first state of charge of the battery based on the power consumption of all individual cells if the selected voltage is greater than the preset battery steady-state voltage. The second determining module 715 is used to determine the second state of charge of the battery based on the mapping relationship between the open circuit voltage of the individual cell and the state of charge of the individual cell if the filtered voltage is not greater than the preset steady-state voltage of the battery.

[0089] Furthermore, the first determining module 714 is specifically used for: Based on the preset unit power consumption current, the first power consumption of the analog front end used for collecting and processing battery data is determined. For each individual cell, determine whether the equalization mode for balancing battery voltage is enabled. If the single cell is in equalization mode, then the second power consumption of the single cell when the equalization mode is activated is determined; the first power consumption and the second power consumption are summed to determine the power consumption of the single cell. If the equalization mode is not enabled for the single cell, the first power consumption is determined as the power consumption of the single cell. Based on the power consumption and initial state of charge, the unit state of charge of the individual battery cell is determined; The first state of charge of the battery is determined by averaging the unit state of charge of all individual cells.

[0090] like Figure 8 As shown, the estimation device 710 further includes: The third determining module 716 is used to determine the third state of charge of the battery based on the mapping relationship between the open circuit voltage of the battery cell and the state of charge of the battery cell when the highest voltage of the battery cell exceeds the preset steady-state voltage of the battery. The difference module 717 is used to determine the difference between the first state of charge and the third state of charge as the transition distance of the battery. The fourth determining module 718 is used to determine the fourth state of charge of the battery based on the transition distance.

[0091] Furthermore, the fourth determining module 718 is specifically used for: Determine whether the transition distance is within a preset difference range; If the transition distance is within a preset difference range, then the gain coefficient corresponding to the transition distance is determined; based on the first state of charge, the third state of charge, and the gain coefficient, the fluctuating state of charge of the battery is determined; If the transition distance is not within the preset difference range, then the third state of charge is determined as the fluctuating state of charge of the battery. The fluctuating state of charge is filtered to obtain the filtered fluctuating state of charge. The minimum value between the filtered fluctuating state of charge and the historical fourth state of charge is determined as the fourth state of charge of the battery; wherein, the historical fourth state of charge is the fourth state of charge of the previous moment of the current moment.

[0092] This application provides a battery state of charge estimation device, which improves the accuracy of battery state of charge estimation when the battery is powered on at low voltage.

[0093] Please see Figure 9 , Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0094] like Figure 9 As shown, the electronic device 900 includes a processor 910, a memory 920, and a bus 930.

[0095] The memory 920 stores machine-readable instructions executable by the processor 910. When the electronic device 900 is running, the processor 910 and the memory 920 communicate via the bus 930. When the machine-readable instructions are executed by the processor 910, they can perform the operations described above. Figure 1 , Figure 3 , Figure 4 , Figure 5 and Figure 6The steps of the battery state of charge estimation method in the method embodiment shown are described in detail in the method embodiment, and will not be repeated here.

[0096] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, can perform the above-described actions. Figure 1 , Figure 3 , Figure 4 , Figure 5 and Figure 6 The steps of the battery state of charge estimation method in the method embodiment shown are described in detail in the method embodiment, and will not be repeated here.

[0097] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems and devices described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division; in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection may be through some communication interfaces; the indirect coupling or communication connection of devices or units may be electrical, mechanical, or other forms.

[0098] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0099] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0100] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0101] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for estimating the state of charge of a battery, characterized in that, The battery includes at least one single cell; the estimation method includes: Obtain the duration of low-voltage battery power-on; When the duration is greater than the preset resting time, the highest voltage is selected from the voltages of all individual cells. Determine whether the filtered voltage is greater than the preset battery steady-state voltage; If the selected voltage is greater than the preset steady-state voltage of the battery, the first state of charge of the battery is determined based on the power consumption of all individual cells. If the selected voltage is not greater than the preset steady-state voltage of the battery, the second state of charge of the battery is determined based on the mapping relationship between the open-circuit voltage of the individual cell and the state of charge of the individual cell.

2. The method for estimating the state of charge of a battery according to claim 1, characterized in that, The determination of the battery's first state of charge based on the power consumption of all individual cells includes: Based on the preset unit power consumption current, the first power consumption of the analog front end used for collecting and processing battery data is determined. For each individual cell, determine whether the equalization mode for balancing battery voltage is enabled. If the single cell is in equalization mode, then the second power consumption of the single cell when the equalization mode is activated is determined; the first power consumption and the second power consumption are summed to determine the power consumption of the single cell. If the equalization mode is not enabled for the single cell, the first power consumption is determined as the power consumption of the single cell. Based on the power consumption and initial state of charge, the unit state of charge of the individual battery cell is determined; The first state of charge of the battery is determined by averaging the unit state of charge of all individual cells.

3. The method for estimating the state of charge of a battery according to claim 1, characterized in that, After determining the first state of charge of the battery based on the power consumption of all individual cells if the selected voltage is greater than the preset steady-state voltage, the estimation method further includes: When the highest voltage of a single battery cell exceeds the preset steady-state voltage, the third state of charge of the battery is determined based on the mapping relationship between the open-circuit voltage of the single cell and the state of charge of the single cell. The difference between the first state of charge and the third state of charge is determined as the transition distance of the battery. Based on the transition distance, the fourth state of charge of the battery is determined.

4. The method for estimating the state of charge of a battery according to claim 3, characterized in that, Determining the fourth state of charge of the battery based on the transition distance includes: Determine whether the transition distance is within a preset difference range; If the transition distance is within a preset difference range, then the gain coefficient corresponding to the transition distance is determined; based on the first state of charge, the third state of charge, and the gain coefficient, the fluctuating state of charge of the battery is determined; If the transition distance is not within the preset difference range, then the third state of charge is determined as the fluctuating state of charge of the battery. The fluctuating state of charge is filtered to obtain the filtered fluctuating state of charge. The minimum value between the filtered fluctuating state of charge and the historical fourth state of charge is determined as the fourth state of charge of the battery; wherein, the historical fourth state of charge is the fourth state of charge of the previous moment of the current moment.

5. A device for estimating the state of charge of a battery, characterized in that, The battery includes at least one single cell; the estimation device includes: The acquisition module is used to acquire the duration of the battery's low-voltage power-on. A screening module is used to select the highest voltage from all individual cells when the duration is greater than a preset resting time. The judgment module is used to determine whether the filtered voltage is greater than the preset battery steady-state voltage. The first determining module is used to determine the first state of charge of the battery based on the power consumption of all individual cells if the selected voltage is greater than the preset steady-state voltage of the battery. The second determining module is used to determine the second state of charge of the battery based on the mapping relationship between the open circuit voltage of the individual cell and the state of charge of the individual cell if the filtered voltage is not greater than the preset steady-state voltage of the battery.

6. The battery state of charge estimation device according to claim 5, characterized in that, The first determining module is specifically used for: Based on the preset unit power consumption current, the first power consumption of the analog front end used for collecting and processing battery data is determined. For each individual cell, determine whether the equalization mode for balancing battery voltage is enabled. If the single cell is in equalization mode, then the second power consumption of the single cell when the equalization mode is activated is determined; the first power consumption and the second power consumption are summed to determine the power consumption of the single cell. If the equalization mode is not enabled for the single cell, the first power consumption is determined as the power consumption of the single cell. Based on the power consumption and initial state of charge, the unit state of charge of the individual battery cell is determined; The first state of charge of the battery is determined by averaging the unit state of charge of all individual cells.

7. The battery state of charge estimation device according to claim 5, characterized in that, The estimation device further includes: The third determination module is used to determine the third state of charge of the battery based on the mapping relationship between the open circuit voltage of the battery cell and the state of charge of the battery cell when the highest voltage of the battery cell exceeds the preset steady-state voltage of the battery. The difference module is used to determine the difference between the first state of charge and the third state of charge as the transition distance of the battery. The fourth determining module is used to determine the fourth state of charge of the battery based on the transition distance.

8. The battery state of charge estimation device according to claim 7, characterized in that, The fourth determining module is specifically used for: Determine whether the transition distance is within a preset difference range; If the transition distance is within a preset difference range, then the gain coefficient corresponding to the transition distance is determined; based on the first state of charge, the third state of charge, and the gain coefficient, the fluctuating state of charge of the battery is determined; If the transition distance is not within the preset difference range, then the third state of charge is determined as the fluctuating state of charge of the battery. The fluctuating state of charge is filtered to obtain the filtered fluctuating state of charge. The minimum value between the filtered fluctuating state of charge and the historical fourth state of charge is determined as the fourth state of charge of the battery; wherein, the historical fourth state of charge is the fourth state of charge of the previous moment of the current moment.

9. An electronic device, characterized in that, include: The device includes a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor communicates with the memory via the bus. The machine-readable instructions are executed by the processor to perform the steps of the battery state-of-charge estimation method as described in any one of claims 1 to 4.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the steps of the battery state-of-charge estimation method as described in any one of claims 1 to 4.

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