Method, device and equipment for determining state of charge of battery and storage medium

Abstract

The invention provides a battery charge state determination method and device, equipment and a storage medium. The method comprises the following steps: determining whether the current of a battery is a preset current threshold value or not; if the current of the battery is the preset current threshold value, when the duration time when the current of the battery is the preset current threshold value reaches the preset time, determining the actual charge state of the battery based on the open-circuit voltage of the battery; if the current of the battery is not the preset current threshold value, determining whether the battery meets a preset special working condition or not; if the battery meets the preset special working condition, determining the actual charge state of the battery based on the battery current of the battery in the preset time period; and if the battery does not meet the preset special working condition, determining the actual state of charge of the battery based on the battery state parameter related to the state of charge of the battery. By adopting the technical scheme provided by the invention, the correction efficiency and accuracy of the state of charge are improved.

Description

TECHNICAL FIELD

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

[0002] A new energy automobile power battery is composed of multiple battery cells. Inconsistent self-discharge rates between the battery cells can cause the state of charge (SOC) of the single battery cells to be inconsistent, thereby affecting the accuracy of power estimation. When the pressure difference between the single battery cells continues to expand, the SOC deviation increases, thereby causing overcharging or overdischarging of the single battery cells. This not only affects the service life of the battery, but also can cause the battery to be scrapped in serious cases. Currently, the commonly used method for estimating the state of charge of the battery includes an open circuit voltage method. The open circuit voltage method is based on a known stable physical relationship between the state of charge of the battery and the open circuit voltage thereof at a given temperature.

[0003] However, the open circuit voltage method can only accurately estimate the state of charge of the battery after the battery is left for a long time, and cannot accurately determine the SOC according to the real-time changing state of the battery. SUMMARY

[0004] Therefore, the embodiments of the present application provide a battery state of charge determination method, device, equipment and storage medium, which determines the state of charge under different states of the battery, and improves the correction efficiency and accuracy of the state of charge.

[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 determination method, which comprises: determining whether the current of the battery is a preset current threshold value; if the current of the battery is the preset current threshold value, determining the actual state of charge of the battery based on the open circuit voltage of the battery when the duration of the current of the battery being the preset current threshold value reaches a preset time; if the current of the battery is not the preset current threshold value, determining whether the battery satisfies a preset special working condition; if the battery satisfies the preset special working condition, determining the actual state of charge of the battery based on the battery current of the battery within a preset time period; if the battery does not satisfy the preset special working condition, determining the actual state of charge of the battery based on a battery state parameter related to the state of charge of the battery.

[0006] Further, when the duration of the current of the battery being the preset current threshold value reaches the preset time, the actual state of charge of the battery is determined based on the open circuit voltage of the battery, which comprises: when the duration of the current of the battery being the preset current threshold value reaches the preset time, obtaining the open circuit voltage of the battery; determine the actual state of charge of the battery corresponding to the open circuit voltage based on a mapping relationship between the open circuit voltage and the state of charge of the battery.

[0007] Further, if the battery meets the preset special working condition, the actual state of charge of the battery is determined based on the battery current of the battery within a preset time period, including: If the battery meets the preset special working condition, the battery current of the battery within a preset time period is obtained; The initial remaining capacity of the battery within the preset time period and the percentage of the actual capacity of the battery are determined as the initial state of charge of the battery; The actual state of charge of the battery is determined based on the battery current and the initial state of charge.

[0008] Further, if the battery does not meet the preset special working condition, the actual state of charge of the battery is determined based on the battery state parameter related to the state of charge of the battery, including: If the battery does not meet the preset special working condition, the battery state parameter related to the state of charge of the battery is obtained; The battery state parameter is input into a second-order equivalent circuit model for estimating the state of charge of the battery to obtain the estimated state of charge of the battery output by the second-order equivalent model; The estimated state of charge of the battery is corrected by using Kalman filtering method, and the corrected estimated state of charge of the battery is determined as the actual state of charge of the battery.

[0009] Further, the determination method further includes: The mapping relationship between the open circuit voltage of the battery and the state of charge of the battery is updated based on the actual state of charge of the battery obtained by using the second-order equivalent model.

[0010] Further, the preset special working condition includes at least one of the following: the battery temperature is less than a preset temperature threshold, and the voltage transfer is performed between a plurality of battery cells.

[0011] In a second aspect, the embodiments of the present application also provide a battery state of charge determination device, the determination device comprising: A first determination module is configured to determine whether the current of the battery is a preset current threshold. A first determination module is configured to determine the actual state of charge of the battery based on the open circuit voltage of the battery if the current of the battery is the preset current threshold when the duration of the current of the battery being the preset current threshold reaches a preset time. A second determination module is configured to determine whether the battery meets a preset special working condition if the current of the battery is not the preset current threshold. The second determining module is configured to determine the actual state of charge of the battery based on the battery current of the battery within a preset time period if the battery meets the preset special working condition. The third determining module is configured to determine the actual state of charge of the battery based on the battery state parameter related to the state of charge of the battery if the battery does not meet the preset special working condition.

[0012] Further, the first determining module is specifically configured to: obtain the open circuit voltage of the battery when the duration of the current of the battery being the preset current threshold value reaches a preset time; determine the actual state of charge of the battery corresponding to the open circuit voltage of the battery based on a mapping relationship between the open circuit voltage of the battery and the state of charge of the battery.

[0013] In a third aspect, an electronic device is provided, including 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 and the memory communicate through the bus, and the machine readable instructions are executed by the processor to perform the steps of the battery state of charge determination method in the first aspect or any possible implementation manner of the first aspect.

[0014] In a fourth aspect, a computer readable storage medium is provided, the computer readable storage medium stores a computer program, and the computer program is executed by the processor to perform the steps of the battery state of charge determination method in the first aspect or any possible implementation manner of the first aspect.

[0015] The battery state of charge determination method, device, equipment and storage medium provided in the embodiments of the present application determine whether the current of the battery is a preset current threshold value; if the current of the battery is the preset current threshold value, when the duration of the current of the battery being the preset current threshold value reaches a preset time, the actual state of charge of the battery is determined based on the open circuit voltage of the battery; if the current of the battery is not the preset current threshold value, it is determined whether the battery meets a preset special working condition; if the battery meets the preset special working condition, the actual state of charge of the battery is determined based on the battery current of the battery within a preset time period; if the battery does not meet the preset special working condition, the actual state of charge of the battery is determined based on the battery state parameter related to the state of charge of the battery.

[0016] In this way, the correction efficiency and accuracy of the state of charge are improved.

[0017] In order to make the above objectives, characteristics and advantages of the present application more apparent and easy to understand, the following preferred embodiments are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor under the guidance of the content of the present application.

[0019] Figure 1 One of the flowcharts of the method for determining the state of charge of a battery provided by the embodiments of the present application is shown; Figure 2 The second flowchart of the method for determining the state of charge of a battery provided by the embodiments of the present application is shown; Figure 3 The third flowchart of the method for determining the state of charge of a battery provided by the embodiments of the present application is shown; Figure 4 The fourth flowchart of the method for determining the state of charge of a battery provided by the embodiments of the present application is shown; Figure 5 The schematic diagram of the second-order equivalent model of a battery provided by the embodiments of the present application is shown; Figure 6 One of the structural schematic diagrams of the device for determining the state of charge of a battery provided by the embodiments of the present application is shown; Figure 7 The second structural schematic diagram of the device for determining the state of charge of a battery provided by the embodiments of the present application is shown; Figure 8 The structural schematic diagram of an electronic device provided by the embodiments of the present application is shown. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of illustration and description, and are not used to limit the protection scope of the present application. In addition, it should be understood that the schematic drawings are not drawn according to the actual proportions. The flowcharts in the present application show the operations implemented according to some of the embodiments of the present application. It should be understood that the operations of the flowcharts can not be implemented in sequence, and the steps without logical contextual relationship can be reversed in sequence or implemented simultaneously. In addition, one or more other operations can be added to the flowcharts or removed from the flowcharts by those skilled in the art under the guidance of the content of the present application.

[0021] In addition, the described embodiments are only some of the embodiments of the present application, not all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0022] The method, device, electronic device or computer readable storage medium described in the embodiments of the present application can be applied to any scene where the determination of the state of charge of the battery is required, and the embodiments of the present application do not limit the specific application scene, and any solution using the method and device for determining the state of charge of the battery provided by the embodiments of the present application is within the protection scope of the present application.

[0023] It is worth noting that the power battery of a new energy vehicle is composed of multiple battery cells, and the inconsistent self-discharge rate between the battery cells will cause the inconsistency of the state of charge (SOC) of the single battery cell, and further affect the accuracy of the power estimation. When the pressure difference between the single battery cells continues to expand, the deviation of the SOC increases, and further causes the overcharge or overdischarge of the single battery cell, which not only affects the service life of the battery, but also may cause the scrapping of the battery in serious cases. At present, the commonly used method for estimating the state of charge of the battery includes the open circuit voltage method. The open circuit voltage method is a method based on the known stable physical relationship between the state of charge of the battery and its open circuit voltage at a given temperature. However, the open circuit voltage method can only accurately estimate the state of charge of the battery after the battery is static for a long time, and cannot accurately determine the SOC according to the real-time changing state of the battery.

[0024] In view of the above problems, the embodiments of the present application provide a method, device and equipment for determining the state of charge of a battery and a storage medium, which determines the state of charge under different states of the battery, and improves the correction efficiency and accuracy of the state of charge.

[0025] In order to facilitate the understanding of the present application, the technical solutions provided by the present application will be described in detail below in combination with specific embodiments.

[0026] In the embodiments of the present application, the battery management system of the vehicle generally adopts a combination of analog front end (AFE) and microcontroller (MCU) to realize advanced management functions. The main responsibility of the AFE is to convert the analog signals such as voltage, current and temperature of the battery into digital signals for subsequent processing by the microcontroller or processor. In addition, the AFE integrates multiple functions, not only optimizes the performance of the battery pack, but also enhances the protection measures of the battery pack, making it adapt to more application scenarios, and ensuring the safe operation and maximum service life of the battery pack. After the vehicle starts, the AFE and MCU will be initialized. The initialization process follows the following timing relationship: first, the MCU completes its initialization, which takes T1 time; then, the AFE and the application layer software are initialized in turn, where the initialization time of the AFE is T2, and the initialization time of the application layer software is T3. After initialization, the underlying software uploads the obtained battery data (voltage, temperature, current, internal resistance, capacity, etc.) to the application layer software for fault judgment and other related processing.

[0027] Referring to Figure 1 , Figure 1 FIG. 1 is a flowchart of a method for determining the state of charge of a battery according to an embodiment of the present application.

[0028] As shown in Figure 1 , the method for determining the state of charge of a battery provided by the present application comprises the following steps: Step S101, determine whether the current of the battery is a preset current threshold.

[0029] Here, the preset current threshold is the current of the battery when it is at rest, and the preset current threshold is zero.

[0030] Step S102, if the current of the battery is the preset current threshold, when the duration of the current of the battery being the preset current threshold reaches a preset time, determine the actual state of charge of the battery based on the open circuit voltage of the battery.

[0031] Here, the duration of the current of the battery being the preset current threshold is the rest time of the battery. As an example, the preset time is 0.5h.

[0032] The following will be described in detail Figure 2 how to determine the actual state of charge of the battery based on the open circuit voltage of the battery.

[0033] Referring to Figure 2 , Figure 2 FIG. 2 is a flowchart of a method for determining the state of charge of a battery according to another embodiment of the present application.

[0034] As shown in Figure 2 , regarding step S102, in specific implementation, as an example, the following steps can be included: Step S1021: When the battery current is at a preset current threshold for a preset duration, the open-circuit voltage of the battery is obtained.

[0035] Step S1022: Based on the mapping relationship between the open-circuit voltage and the state of charge of the battery, determine the actual state of charge of the battery corresponding to the open-circuit voltage.

[0036] Here, as an example, the mapping relationship between the open-circuit voltage and the state of charge of a lithium iron phosphate battery is shown in Table 1.

[0037] Table 1. Mapping relationship between battery open-circuit voltage and battery state of charge.

[0038] Regarding step S1022, as an example, assuming the open-circuit voltage of a lithium iron phosphate battery is 3.4823V, according to the table lookup, the actual state of charge of the current battery is 15%. After the battery has been left to rest for a sufficiently long time, the OCV-SOC (open-circuit voltage - state of charge) lookup table provides an absolute reference SOC point, which is used to correct the cumulative error of the ampere-hour integration.

[0039] Step S103: If the battery current is not less than the preset current threshold, then determine whether the battery meets the preset special operating conditions.

[0040] Here, the special operating condition refers to the battery being in an unconventional operating state. For example, the battery is in a low-temperature condition and the charging mode is equalization charging mode. The condition for determining the battery's low-temperature condition is that the battery current is less than a preset current threshold; here, for example, the preset current threshold is -20℃. The condition for determining the battery mode is that voltage transfer occurs between the multiple cells.

[0041] Step S104: If the battery meets the preset special operating conditions, the actual state of charge of the battery is determined based on the battery current within the preset time period.

[0042] The following is combined Figure 3 This section will explain in detail how to determine the actual state of charge of a battery based on its current over a preset time period.

[0043] Please see Figure 3 , Figure 3 This is the third flowchart of a method for determining the state of charge of a battery provided in an embodiment of this application.

[0044] like Figure 3 As shown, regarding step S103, in a specific implementation, as an example, the following steps may be included: Step S1031, if the battery meets the preset special working condition, the battery current of the battery in the preset time period is obtained.

[0045] Here, the preset time period is a time period that is set at an interval from the current time. When the battery is in a special working condition, the actual state of charge of the current battery is determined using the ampere-hour integration method.

[0046] Step S1032, the initial remaining capacity of the battery in the preset time period and the percentage of the actual capacity of the battery are determined as the initial state of charge of the battery.

[0047] Here, the actual capacity of the battery is updated using complete charging or discharging capacity data.

[0048] Step S1033, based on the battery current and the initial state of charge, the actual state of charge of the battery is determined.

[0049] Here, as an example, the calculation formula corresponding to the actual state of charge of the battery obtained using the ampere-hour integration method can be expressed using formula (1).

[0050] (1) wherein, SoC(t) is the state of charge at time t, i.e. the current actual state of charge of the battery; t SoC(t0) is the state of charge at initial time t0, i.e. the state of charge at the initial time of the preset time period; C is the rated capacity of the battery (unit: Ah), for example, a 100 Ah battery, _nominal 100; C _nominal Coulomb efficiency, in the charging process ≤1 (the charging process is accompanied by energy loss), and in the discharging process, the efficiency coefficient η ≈1. For batteries such as lithium iron phosphate, the charging and discharging efficiency is very high, and is often approximately 1; at time η I(t) is the instantaneous current at time t (unit: A), in the charging process, the current τ is positive, indicating that the current is flowing into the battery, and in the discharging process, the current is negative, indicating that the current is flowing out of the battery; the integral sign indicates that the current in the preset time period is integrated, representing the net amount of current flowing in or out in the preset time period. Step S105, if the battery does not meet the preset special working condition, the actual state of charge of the battery is determined based on the battery state parameter related to the state of charge of the battery.

[0051]

[0052] Here, the battery state parameters of the battery include: voltage, current, internal resistance, capacity, and health, etc.

[0053] The following will be specifically explained Figure 4 how to determine the actual state of charge of the battery based on the battery state parameters related to the state of charge of the battery.

[0054] Please refer to Figure 4 , Figure 4 the fourth flowchart of the method for determining the state of charge of the battery provided by the embodiments of the present application.

[0055] As shown in Figure 4 , regarding step S105, in specific implementation, as an example, the following steps can be included: Step S1051, if the battery does not meet the preset special working condition, the battery state parameters related to the state of charge of the battery are obtained.

[0056] Step S1052, the battery state parameters are input into the second-order equivalent circuit model for estimating the state of charge of the battery, so as to obtain the estimated state of charge of the battery output by the second-order equivalent model.

[0057] Here, the present application constructs a battery digital twin system with learning and adaptation capability, that is, through multi-dimensional monitoring of the battery state in the cloud, the state of charge of the battery is corrected in the cloud. As shown in Figure 5 , a model capable of accurately mapping the real physical characteristics of the battery, i.e. a second-order equivalent model, is established in the cloud.

[0058] As shown in Figure 5 , the output equation of the second-order equivalent model in the time domain can be represented by formula (2).

[0059] (2).

[0060] Wherein, U L is the circuit terminal voltage, U oc is the open circuit voltage, I L is the current flowing through the circuit, R 0 is the ohmic internal resistance, R 1、 R 2 is the polarization resistance, C 1、 C 2 is the polarization capacitance. Here, the parameters in the model include ohmic internal resistance R 0, polarization resistance R 1、 R 2, and polarization capacitance C 1、 C2, not fixed value. These parameters are the function of state of charge (SOC), temperature (T), state of health (SOH) and the number of charge and discharge cycles. For example, the temperature decreases, the viscosity of the electrolyte increases, the lithium ion migration rate slows down, and the internal resistance increases sharply. At this time, the ohmic resistance can be obtained by formula (3).

[0061] (3).

[0062] wherein, , and are parameters obtained according to actual experience, is the absolute temperature. In the cloud, by applying online parameter identification algorithms such as recursive least squares (RLS) and least squares with forgetting factor (FFRLS), the model parameters can be updated in real time, so as to ensure that the model is always close to the actual state of the battery.

[0063] Definition , is the circuit impedance, then the circuit impedance can be represented by formula (4).

[0064] (4).

[0065] wherein, τ 1= R 1 C 1, τ 2= R 2 C 2, according to the principle of bilinear transformation, wherein, T is the sampling period, and the discrete transfer function formula (5) can be obtained.

[0066] (5).

[0067] wherein, β 0, β 1, β 2, α 1, α 2is a matrix vector.

[0068] The discrete difference equation of

[0069] (6).

[0070] Let , , formula (6) can be written in the form of recursive least squares as shown in formula (7).

[0071] (7).

[0072] in, For the error term, This is the estimated state of charge of the battery.

[0073] Step S1053: The estimated state of charge of the battery is corrected using the Kalman filter method, and the corrected estimated state of charge of the battery is determined as the actual state of charge of the battery.

[0074] In this embodiment, a state-space equation for a second-order equivalent model is constructed. This state-space equation is then combined with state parameters, and a Kalman filter is applied to determine the actual state of charge (SOC) of the battery. The initial value is the estimated SOC of the battery, and the Kalman filter is used to correct this estimated SOC.

[0075] In one possible implementation, the determination method further includes: updating the mapping relationship between the battery's open-circuit voltage and the battery's state of charge based on the actual state of charge of the battery obtained using a second-order equivalent model. Here, when it is detected that the OCV-SOC curve has drifted due to aging, resulting in the numerical relationship of the corresponding OCV under the same SOC deviating from the original calibration curve, the OCV-SOC curve is updated using the actual state of charge of the battery obtained from the second-order equivalent model and its corresponding open-circuit voltage.

[0076] This application provides a method for determining the state of charge of a battery, which improves the efficiency and accuracy of state of charge correction.

[0077] Based on the same application concept, this application also provides a battery state of charge determination device corresponding to the battery state of charge determination method provided in the above embodiments. Since the principle of the device in this application is similar to the battery state of charge determination 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.

[0078] like Figure 6 to Figure 7 As shown, Figure 6 This is one of the structural schematic diagrams of a battery state of charge determination device provided in an embodiment of this application. Figure 7 This is a second schematic diagram of a device for determining the state of charge of a battery, provided in an embodiment of this application.

[0079] like Figure 6 As shown in the embodiment of this application, the battery state of charge determination device 610 includes: The first judgment module 611 is used to determine whether the battery current is a preset current threshold. The first determination module 612 is configured to: if the current of the battery is the preset current threshold, and the duration that the current of the battery is the preset current threshold reaches the preset time, determine the actual state of charge of the battery based on the open circuit voltage of the battery. The second determination module 613 is configured to: if the current of the battery is not the preset current threshold, determine whether the battery satisfies the preset special working condition. The second determination module 614 is configured to: if the battery satisfies the preset special working condition, determine the actual state of charge of the battery based on the battery current of the battery within a preset time period. The third determination module 615 is configured to: if the battery does not satisfy the preset special working condition, determine the actual state of charge of the battery based on the battery state parameter related to the state of charge of the battery.

[0080] Further, the first determination module 612 is specifically configured to: acquire the open circuit voltage of the battery when the duration that the current of the battery is the preset current threshold reaches the preset time; determine the actual state of charge of the battery corresponding to the open circuit voltage based on a mapping relationship between the open circuit voltage of the battery and the state of charge of the battery.

[0081] Further, the second determination module 614 is specifically configured to: if the battery satisfies the preset special working condition, acquire the battery current of the battery within a preset time period; determine the initial state of charge of the battery as a percentage of the actual capacity of the battery and the initial remaining capacity of the battery within the preset time period; determine the actual state of charge of the battery based on the battery current and the initial state of charge.

[0082] Further, the third determination module 615 is specifically configured to: if the battery does not satisfy the preset special working condition, acquire the battery state parameter related to the state of charge of the battery; input the battery state parameter into a second-order equivalent circuit model used for estimating the state of charge of the battery, to acquire the estimated state of charge of the battery output by the second-order equivalent model; correct the estimated state of charge of the battery by using a Kalman filtering method, and determine the corrected estimated state of charge of the battery as the actual state of charge of the battery.

[0083] As shown in the first aspect of the present application, Figure 7 Further, the determination apparatus 610 further includes: The updating module 616 is configured to update the mapping relationship between the open circuit voltage of the battery and the state of charge of the battery based on the actual state of charge of the battery obtained by using the second-order equivalent model.

[0084] Further, the preset special working condition includes at least one of the following: the battery temperature is less than a preset temperature threshold, and voltage transfer is performed between a plurality of battery cells.

[0085] The device for determining the state of charge of a battery provided by the embodiments of the present application improves the correction efficiency and accuracy of the state of charge.

[0086] Please refer to Figure 8 , Figure 8 The structural schematic diagram of an electronic device provided by the embodiments of the present application.

[0087] As Figure 8 shown in the figure, the electronic device 800 includes a processor 810, a memory 820 and a bus 830.

[0088] The memory 820 stores machine readable instructions executable by the processor 810, when the electronic device 800 is running, the processor 810 and the memory 820 communicate through the bus 830, and the machine readable instructions executed by the processor 810 can execute the steps of the method for determining the state of charge of a battery in the method embodiments as described above Figure 1 , Figure 2 , Figure 3 and Figure 4 , and the specific implementation manner can be referred to the method embodiments, which will not be described here.

[0089] The embodiments of the present application also provide a computer readable storage medium, the computer readable storage medium stores a computer program, and the computer program can execute the steps of the method for determining the state of charge of a battery in the method embodiments as described above Figure 1 , Figure 2 , Figure 3 and Figure 4 when the computer program is run by the processor, and the specific implementation manner can be referred to the method embodiments, which will not be described here.

[0090] Those skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working process of the system and the device described above can refer to the corresponding process in the foregoing method embodiment, and will not be repeated here. In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are only schematic, for example, the division of the units is only a logical function division, and there can be another division manner in actual implementation, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some communication interfaces, devices or units, and can be electrical, mechanical or other forms.

[0091] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., they can be located in one place or distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0092] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit.

[0093] If the functions are realized in the form of software function units and sold or used as independent products, they can be stored in a non-volatile computer readable storage medium executable by a processor. Based on this understanding, the technical solutions of the present application essentially or the parts that contribute to the prior art or the parts of the technical solutions can be embodied in the form of software products, and the computer software products are stored in a storage medium, including a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the embodiments of the present application. The foregoing storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), magnetic disk or optical disk, and various program code storage media.

[0094] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method of determining a state of charge of a battery, characterized by, The determination method comprises: determining whether the current of the battery is a preset current threshold value; if the current of the battery is the preset current threshold value, when the duration of the current of the battery being the preset current threshold value reaches a preset time, determining the actual state of charge of the battery based on the open circuit voltage of the battery; if the current of the battery is not the preset current threshold value, determining whether the battery meets a preset special working condition; if the battery meets the preset special working condition, determining the actual state of charge of the battery based on the battery current of the battery within a preset time period; if the battery does not meet the preset special working condition, determining the actual state of charge of the battery based on a battery state parameter related to the state of charge of the battery.

2. The method of determining the state of charge of a battery according to claim 1, wherein, The determination method comprises: if the battery meets the preset special working condition, obtaining the battery current of the battery within the preset time period; determining the initial state of charge of the battery as the percentage of the initial remaining capacity of the battery within the preset time period to the actual capacity of the battery; 3. The method of determining state of charge of a battery according to claim 1, wherein, determining the actual state of charge of the battery based on the battery current and the initial state of charge. The determination method comprises: if the battery does not meet the preset special working condition, obtaining the battery state parameter related to the state of charge of the battery; inputting the battery state parameter into a second-order equivalent circuit model used for estimating the state of charge of the battery to obtain a battery estimated state of charge output by the second-order equivalent model; 4. The method of determining state of charge of a battery according to claim 1, wherein, using Kalman filtering method to correct the battery estimated state of charge, and determining the corrected battery estimated state of charge as the actual state of charge of the battery. The determination method further comprises: updating the mapping relationship between the open circuit voltage of the battery and the state of charge of the battery based on the actual state of charge of the battery obtained by using the second-order equivalent model. The preset special working condition comprises at least one of the following: the battery temperature is less than a preset temperature threshold value, and voltage transfer is performed between a plurality of battery cells of the battery.

5. The method of determining state of charge of a battery according to claim 4, wherein, The determination device comprises: a first determination module, configured to determine whether the current of the battery is a preset current threshold value; 6. The method of determining state of charge of a battery according to claim 1, wherein, a first determination module, configured to, if the current of the battery is the preset current threshold value, when the duration of the current of the battery being the preset current threshold value reaches a preset time, determine the actual state of charge of the battery based on the open circuit voltage of the battery; 7. A device for determining the state of charge of a battery, characterized in that a second determination module, configured to, if the current of the battery is not the preset current threshold value, determine whether the battery meets a preset special working condition; a third determination module, configured to, if the battery meets the preset special working condition, determine the actual state of charge of the battery based on the battery current of the battery within a preset time period; and a fourth determination module, configured to, if the battery does not meet the preset special working condition, determine the actual state of charge of the battery based on a battery state parameter related to the state of charge of the battery. ​ The second determining module is configured to determine the actual state of charge of the battery based on the battery current of the battery within a preset time period if the battery meets the preset special working condition; The third determining module is configured to determine the actual state of charge of the battery based on the battery state parameter related to the state of charge of the battery if the battery does not meet the preset special working condition.

8. The apparatus for determining state of charge of a battery according to claim 7, wherein, The first determining module is specifically configured to: When the duration of the current of the battery being the preset current threshold reaches a preset time, acquire the open circuit voltage of the battery; Determine the actual state of charge of the battery corresponding to the open circuit voltage of the battery based on the mapping relationship between the open circuit voltage of the battery and the state of charge of the battery.

9. An electronic device, comprising: The method comprises: 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 and the memory communicate through the bus, the machine readable instructions are executed by the processor to execute the steps of the battery state of charge determination method in any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that, The computer readable storage medium stores a computer program, the computer program is executed by the processor to execute the steps of the battery state of charge determination method in any one of claims 1 to 6.

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