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

Abstract

The application discloses a power battery state of charge estimation method, device, equipment and storage medium, the power battery includes a plurality of electric cores, the estimation method includes determining the current highest available capacity and the current lowest available capacity of the electric core; determining the current health degree of the power battery; according to the rated capacity, the previous maximum value and the previous minimum value of the state of charge of the power battery, the current consistency deviation capacity is determined;According to the current highest available capacity, the current lowest available capacity, the current health degree and the current consistency deviation capacity, the current maximum value and the current minimum value of the state of charge are determined;According to the current maximum value and the current minimum value, the current true value of the state of charge is determined. Wherein, by introducing the battery consistency deviation capacity, the current true value of the state of charge is estimated, the SOC estimation error caused by the battery inconsistency is eliminated, and the accuracy of SOC estimation is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power batteries, and particularly relates to a power battery state of charge estimation method, device, equipment and storage medium. BACKGROUND

[0002] In a power battery management system of an electric vehicle, the state of charge (SOC) of the power battery is an indispensable parameter for balance control technology, fast charging and discharging management, long service life and safe operation. Accurate estimation of the SOC of the power battery can avoid damage to the power battery, reasonably utilize the power provided by the power battery, improve the utilization rate of the battery, and prolong the service life of the battery pack.

[0003] In the current SOC estimation method, the SOC estimation deviation is large, and the problems of actual SOC being less than full charge SOC at the end of charging or actual SOC reaching 0 in advance at the end of discharging are prone to occur. SUMMARY

[0004] Embodiments of the application provide a power battery state of charge estimation method, device, equipment and storage medium, which can improve the accuracy of SOC estimation.

[0005] Other characteristics and advantages of the application will become apparent from the following detailed description, or will be learned by practice of the application.

[0006] According to a first aspect of the embodiments of the application, a power battery state of charge estimation method is provided, the power battery comprising a plurality of battery cells, and the power battery state of charge estimation method comprising:

[0007] determining a current maximum available capacity and a current minimum available capacity of the battery cell;

[0008] determining a current health degree of the power battery;

[0009] determining a current consistency deviation capacity according to a rated capacity, a previous maximum value and a previous minimum value of the state of charge of the power battery;

[0010] determining a current maximum value and a current minimum value of the state of charge according to the current maximum available capacity, the current minimum available capacity, the current health degree and the current consistency deviation capacity;

[0011] determining a current true value of the state of charge according to the current maximum value and the current minimum value.

[0012] In some embodiments of this application, based on the foregoing scheme, determining the current consistency deviation capacity according to the rated capacity, the previous maximum value and the previous minimum value of the state of charge of the power battery includes:

[0013] The current consistency deviation capacity is obtained based on the rated capacity of the power battery, the previous maximum value, the previous minimum value, and the following formula:

[0014] Q1 = Q R *(1-SOC max0 +SOC min0 );

[0015] Where Q1 is the current consistency deviation capacity, Q R For the rated capacity, SOC max0 For the previous maximum value, SOC min0 This is the previous minimum value.

[0016] In some embodiments of this application, based on the foregoing scheme, determining the current maximum and minimum values ​​of the state of charge according to the current highest available capacity, the current lowest available capacity, the current health status, and the current consistency deviation capacity includes:

[0017] The current maximum value is obtained based on the current highest available capacity, the current health status, the current consistency deviation capacity, and the following formula:

[0018]

[0019] Among them, SOC max1 Q is the current maximum value. max1 The highest available capacity is defined as SOH1, and the current health status is defined as SOH1.

[0020] The current minimum value is obtained based on the current minimum available capacity, the current health status, the current consistency deviation capacity, and the following formula:

[0021]

[0022] Among them, SOC min1 Q is the current minimum value. min1 This represents the current minimum available capacity.

[0023] In some embodiments of this application, based on the foregoing scheme, determining the current true value of the state of charge according to the current maximum value and the current minimum value includes:

[0024] The current true value is obtained based on the current maximum value, the current minimum value, and the following formula:

[0025]

[0026] Among them, SOC real This is the current true value.

[0027] In some embodiments of this application, based on the foregoing scheme, determining the current highest available capacity and the current lowest available capacity of the battery cell includes:

[0028] Obtain the previous maximum value, previous minimum value, and previous health status of the charge state;

[0029] The product of the previous maximum value, the previous health status, and the rated capacity is determined as the current highest available capacity;

[0030] The product of the previous minimum value, the previous health status, and the rated capacity is determined as the current maximum available capacity.

[0031] In some embodiments of this application, based on the foregoing scheme, determining the current health of the power battery includes:

[0032] Obtain the current capacity change and the current state of charge change of the power battery;

[0033] The current health status is obtained based on the current capacity change, the current state of charge change, and the rated capacity.

[0034] In some embodiments of this application, based on the foregoing scheme, obtaining the current health status according to the current capacity change, the current state of charge change, and the rated capacity includes:

[0035] The current health status is obtained based on the current capacity change, the current state of charge change, the rated capacity, and the following formula:

[0036]

[0037] Where SOH1 is the current health status, ΔQ1 is the current capacity change, ΔSOC1 is the current state of charge change, and Q... R The rated capacity is [the specified capacity].

[0038] According to a second aspect of the embodiments of this application, a device for estimating the state of charge (SOC) of a power battery is provided. The power battery includes a plurality of cells, and the device for estimating the SOC of the power battery includes:

[0039] A capacity determination unit is used to determine the current highest available capacity and the current lowest available capacity of the battery cell;

[0040] A health determination unit is used to determine the current health status of the power battery;

[0041] The capacity deviation unit is used to determine the current consistency deviation capacity based on the rated capacity, the previous maximum value and the previous minimum value of the state of charge of the power battery.

[0042] The SOC extreme value determination unit is used to determine the current maximum and minimum values ​​of the state of charge based on the current highest available capacity, the current lowest available capacity, the current health status, and the current consistency deviation capacity.

[0043] The SOC true value determination unit is used to determine the current true value of the state of charge based on the current maximum value and the current minimum value.

[0044] In some embodiments of this application, based on the foregoing scheme, the capacity deviation unit is further configured to obtain the current consistency deviation capacity according to the rated capacity of the power battery, the previous maximum value, the previous minimum value, and the following formula:

[0045] Q1 = Q R *(1-SOC max0 +SOC min0 );

[0046] Where Q1 is the current consistency deviation capacity, Q R For rated capacity, SOC max0 SOC is the previous maximum value. min0 It is the previous minimum value.

[0047] In some embodiments of this application, based on the foregoing scheme, the SOC extreme value determination unit is further configured to obtain the current maximum value according to the current highest available capacity, the current health status, the current consistency deviation capacity, and the following formula:

[0048]

[0049] Among them, SOC max1 Q is the current maximum value. max1 The highest available capacity is defined as SOH1, and the current health status is defined as SOH1.

[0050] The current minimum value is obtained based on the current minimum available capacity, the current health status, the current consistency deviation capacity, and the following formula:

[0051]

[0052] Among them, SOC min1 Q is the current minimum value.min1 This represents the current minimum available capacity.

[0053] In some embodiments of this application, based on the foregoing scheme, the SOC true value determination unit is further configured to obtain the current true value according to the current maximum value, the current minimum value, and the following formula:

[0054]

[0055] Among them, SOC real This is the current actual value.

[0056] In some embodiments of this application, based on the aforementioned scheme, the capacity determination unit is further configured to obtain the previous maximum value, the previous minimum value, and the previous health status of the state of charge; determine the product of the previous maximum value, the previous health status, and the rated capacity as the current highest available capacity; and determine the product of the previous minimum value, the previous health status, and the rated capacity as the current highest available capacity.

[0057] In some embodiments of this application, based on the aforementioned scheme, the health determination unit is further configured to obtain the current capacity change and the current state of charge change of the power battery; and to obtain the current health status based on the current capacity change, the current state of charge change, and the rated capacity.

[0058] In some embodiments of this application, based on the foregoing scheme, the health determination unit is further configured to obtain the current health status according to the current capacity change, the current state of charge change, the rated capacity, and the following formula:

[0059]

[0060] Where SOH1 is the current health status, ΔQ1 is the current capacity change, ΔSOC1 is the current state of charge change, and Q... R This is the rated capacity.

[0061] According to a third aspect of the present application, a power battery state of charge estimation device is provided. The power battery state of charge estimation device includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the above-described method.

[0062] According to a fourth aspect of the embodiments of this application, a computer-readable storage medium is provided, on which a computer program is stored, wherein the computer program, when executed by a processor, implements the steps of the method described above.

[0063] In this application, the current highest and lowest available capacity of the battery cell are determined; the current health of the power battery is determined; the current consistency deviation capacity is determined based on the rated capacity of the power battery, the previous maximum and minimum values ​​of the state of charge (SOC); the current maximum and minimum values ​​of the SOC are determined based on the current highest available capacity, the current lowest available capacity, the current health, and the current consistency deviation capacity; and the current true value of the SOC is determined based on the current maximum and minimum values. By introducing the battery consistency deviation capacity to estimate the current true value of the SOC, the estimation error caused by battery inconsistency is eliminated, thus improving the accuracy of SOC estimation.

[0064] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0065] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0066] Figure 1 This is a flowchart illustrating a method for estimating the state of charge of a power battery in one embodiment;

[0067] Figure 2 for Figure 1 A flowchart illustrating step 101;

[0068] Figure 3 for Figure 1 A flowchart illustrating step 102 in the middle section;

[0069] Figure 4 This is a structural block diagram of a power battery state-of-charge estimation device in one embodiment;

[0070] Figure 5 This is an internal structural diagram of a device for estimating the state of charge of a power battery in one embodiment. Detailed Implementation

[0071] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0072] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0073] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0074] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0075] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such uses of these terms can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described.

[0076] Figure 1 This is a flowchart illustrating a method for estimating the state of charge of a power battery in one embodiment, as shown below. Figure 1 As shown, a method for estimating the state of charge of a power battery is provided. The power battery includes multiple cells, and the method may include the following steps:

[0077] Step 101: Determine the current highest available capacity and the current lowest available capacity of the battery cell.

[0078] It should be understood that when a power battery contains multiple cells, the actual capacity of each cell may differ during charging and discharging. Conventional SOC estimation methods do not take into account the impact of battery pack consistency on SOC, resulting in a large deviation in the estimated SOC. This embodiment introduces the battery consistency deviation capacity, and the current maximum and minimum values ​​of the state of charge calculated based on this consistency deviation capacity are more accurate than those of existing technologies. Consequently, the current true value of the state of charge is more accurate, effectively preventing the problem that the current true value of the state of charge is less than the full charge SOC when the battery reaches full charge at the end of charging, and that the current true value reaches 0 at the end of discharging.

[0079] It should be noted that during the charging and discharging process of the power battery, the maximum and minimum available capacity of the cell need to be continuously calculated. Therefore, the current maximum available capacity refers to the maximum available capacity of the cell at the current moment, and the current minimum available capacity refers to the minimum available capacity of the cell at the current moment.

[0080] Taking the application of this method to a Battery Management System (BMS) as an example, the BMS can calculate the current maximum and minimum available capacity of the battery cells in real time through various methods. In one example, the BMS can use ampere-hour integration to calculate the current capacity change of the power battery, and then calculate the current maximum and minimum available capacity based on the rated capacity of the power battery and the current capacity change.

[0081] In another example, such as Figure 2 As shown, determining the current highest and lowest available capacity of a battery cell may include the following steps:

[0082] Step 201: Obtain the previous maximum value, previous minimum value, and previous health status of the state of charge; Step 202: Determine the current highest available capacity by multiplying the previous maximum value, previous health status, and rated capacity; Step 203: Determine the current lowest available capacity by multiplying the previous minimum value, previous health status, and rated capacity.

[0083] During the charging and discharging process of a power battery, it is necessary to continuously calculate the maximum and minimum values ​​of the state of charge and the health of the power battery. Therefore, the current maximum value refers to the maximum value of the state of charge at the current moment, the current minimum value refers to the minimum value of the state of charge at the current moment, and the current health refers to the health of the power battery at the current moment. The previous maximum value refers to the maximum value of the state of charge at the moment before the current moment, the previous minimum value refers to the minimum value of the state of charge at the moment before the current moment, and the previous health refers to the health of the battery cell at the moment before the current moment.

[0084] Specifically, the current minimum available capacity can be calculated using Formula 1:

[0085] Q min1 =SOH0*Q R *SOC min0 Formula 1;

[0086] The current maximum available capacity can be calculated using Formula 2:

[0087] Q max1 =SOH0*Q R *SOC max0 Formula 2;

[0088] Among them, Q min1 Q represents the minimum available capacity at present. max1 The highest available capacity is currently specified, SOH0 represents the previous health status, and Q represents the current maximum available capacity. R For rated capacity, SOC min0 SOC is the previous minimum value. max0 This is the previous maximum value.

[0089] Because the cell degradation factor is taken into account in the calculation, the calculated current maximum and minimum available capacities are more accurate, providing the conditions for accurate SOC calculation.

[0090] Step 102: Determine the current health status of the power battery.

[0091] It should be understood that the health of a power battery changes continuously as it is charged and discharged. The BMS can calculate the current health of the power battery in various ways. In one example, the ratio of the current available capacity to the rated capacity of the power battery can be used as the current health.

[0092] In another example, such as Figure 3 As shown, determining the current health of a power battery may include the following steps:

[0093] Step 301: Obtain the current capacity change and the current state of charge change of the power battery; Step 302: Obtain the current health status based on the current capacity change, the current state of charge change, and the rated capacity.

[0094] Because the capacity and state of charge of the power battery are constantly changing during the charging and discharging process, the BMS needs to continuously calculate the changes in capacity and state of charge. The current capacity change refers to the change in the capacity of the power battery at the current moment, and the current state of charge change refers to the change in the state of charge of the power battery at the current moment.

[0095] Among them, the BMS can calculate the current capacity change of the power battery by using ampere-hour integration based on the change of current during the charging and discharging process. The BMS can also look up the current state of charge change by looking up the cell voltage during the charging and discharging process.

[0096] It should be noted that after obtaining the current capacity change and the current state of charge change, the BMS can multiply the current state of charge change by the rated capacity to obtain the theoretical capacity change, and then divide the current capacity change by the theoretical capacity change to obtain the current health status. In other words, the current health status can be determined using Formula 3:

[0097]

[0098] Where SOH1 is the current health status, ΔQ1 is the current capacity change, ΔSOC1 is the current state of charge change, and Q... R This is the rated capacity.

[0099] Step 103: Determine the current consistency deviation capacity based on the rated capacity of the power battery, the previous maximum value of the state of charge, and the previous minimum value of the state of charge.

[0100] Specifically, BMS can determine the current consistency deviation capacity using various calculation formulas. In one example, the current consistency deviation capacity is determined using Formula 4:

[0101] Q1 = Q R *(1-SOC max0 +SOC min0 Formula 4;

[0102] Where Q1 is the current consistency deviation capacity, Q R For rated capacity, SOC max0 SOC is the previous maximum value. min0 It is the previous minimum value.

[0103] Step 104: Determine the current maximum and minimum values ​​of the state of charge based on the current highest available capacity, the current lowest available capacity, the current health status, and the current consistency deviation capacity.

[0104] Specifically, the BMS can determine the current maximum and minimum values ​​using various calculation formulas. In one example, the current maximum value can be determined using formula five, and the current minimum value can be determined using formula six:

[0105]

[0106]

[0107] Among them, Q max1Q represents the highest currently available capacity. min1 SOH1 represents the current minimum available capacity and the current health status.

[0108] It should be noted that if the capacity deviation caused by consistency is not considered when calculating the current maximum and minimum values, the calculated maximum and minimum values ​​will be too large. As a result, the actual SOC of the power battery calculated in this way will have the problem of reaching 0 before discharge and being less than the full charge SOC when the full charge is cut off. By introducing the consistency deviation capacity, the current maximum and minimum values ​​can be accurately calculated, thereby solving the above problems.

[0109] Step 105: Determine the current true value of the state of charge based on the current maximum value and the current minimum value.

[0110] It should be understood that during the charging and discharging process of the power battery, the state of charge of the power battery is constantly changing. The BMS needs to continuously calculate the true value of the state of charge. The current true value refers to the true value of the state of charge of the power battery at the current moment.

[0111] Specifically, the BMS can determine the current true value of the state of charge using various calculation formulas. In one example, the current true value can be determined using Formula 7:

[0112]

[0113] Among them, SOC real This is the current actual value.

[0114] This embodiment determines the current highest and lowest available capacity of the battery cell; determines the current health of the power battery; determines the current consistency deviation capacity based on the rated capacity of the power battery, the previous maximum and minimum values ​​of the state of charge (SOC); determines the current maximum and minimum values ​​of the SOC based on the current highest available capacity, the current lowest available capacity, the current health, and the current consistency deviation capacity; and determines the current true value of the SOC based on the current maximum and minimum values. By introducing the battery consistency deviation capacity to estimate the current true value of the SOC, the estimation error caused by battery inconsistency is eliminated, improving the accuracy of SOC estimation and effectively preventing the problem of the true SOC of the power battery reaching 0 prematurely at the end of discharge and the problem of the true SOC being less than the full-charge SOC at the end of full charge.

[0115] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0116] Based on the same inventive concept, embodiments of this application also provide a device for estimating the state of charge of a power battery, such as... Figure 4 As shown, the power battery state of charge estimation device may include: a capacity determination unit 401, a health determination unit 402, a capacity deviation unit 403, a SOC extreme value determination unit 404, and a SOC true value determination unit 405, wherein: the capacity determination unit 401 is used to determine the current highest available capacity and the current lowest available capacity of the battery cell; the health determination unit 402 is used to determine the current health of the power battery; the capacity deviation unit 403 is used to determine the current consistency deviation capacity based on the rated capacity of the power battery, the previous maximum value and the previous minimum value of the state of charge; the SOC extreme value determination unit 404 is used to determine the current maximum value and the current minimum value of the state of charge based on the current highest available capacity, the current lowest available capacity, the current health, and the current consistency deviation capacity; and the SOC true value determination unit 405 is used to determine the current true value of the state of charge based on the current maximum value and the current minimum value.

[0117] In some embodiments of this application, based on the foregoing scheme, the capacity deviation unit 403 is further configured to obtain the current consistency deviation capacity according to the rated capacity of the power battery, the previous maximum value, the previous minimum value, and the following formula:

[0118] Q1 = Q R *(1-SOC max0 +SOC min0 );

[0119] Where Q1 is the current consistency deviation capacity, Q R For rated capacity, SOC max0 SOC is the previous maximum value. min0 It is the previous minimum value.

[0120] In some embodiments of this application, based on the foregoing scheme, the SOC extreme value determination unit 404 is further configured to obtain the current maximum value based on the current highest available capacity, the current health status, the current consistency deviation capacity, and the following formula:

[0121]

[0122] Among them, SOC max1 Q is the current maximum value. max1 The highest available capacity is represented by SOH1, and the current health status is represented by SOH1. The current minimum value is obtained based on the lowest available capacity, current health status, current consistency deviation capacity, and the following formula:

[0123]

[0124] Among them, SOC min1 Q is the current minimum value. min1 This represents the current minimum available capacity.

[0125] In some embodiments of this application, based on the foregoing scheme, the SOC true value determination unit 405 is further configured to obtain the current true value according to the current maximum value, the current minimum value, and the following formula:

[0126]

[0127] Among them, SOC real This is the current actual value.

[0128] In some embodiments of this application, based on the aforementioned scheme, the capacity determination unit 401 is further configured to obtain the previous maximum value, the previous minimum value, and the previous health status of the state of charge; determine the product of the previous maximum value, the previous health status, and the rated capacity as the current highest available capacity; and determine the product of the previous minimum value, the previous health status, and the rated capacity as the current highest available capacity.

[0129] In some embodiments of this application, based on the aforementioned scheme, the health determination unit 402 is further configured to obtain the current capacity change and the current state of charge change of the power battery; and to obtain the current health status based on the current capacity change, the current state of charge change, and the rated capacity.

[0130] In some embodiments of this application, based on the foregoing scheme, the health determination unit 402 is further configured to obtain the current health status based on the current capacity change, the current state of charge change, the rated capacity, and the following formula:

[0131]

[0132] Where SOH1 is the current health status, ΔQ1 is the current capacity change, ΔSOC1 is the current state of charge change, and Q... R This is the rated capacity.

[0133] Each module in the aforementioned power battery state-of-charge estimation device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the computer device's memory as software, so that the processor can call and execute the corresponding operations of each module.

[0134] Based on the same inventive concept, this application also provides a device for estimating the state of charge of a power battery. Figure 5 Here is an internal structural diagram of a power battery state-of-charge estimation device in one embodiment, such as... Figure 5 As shown, the power battery state of charge estimation device includes one or more memories 504, one or more processors 502, and at least one computer program (program code) stored in the memory 504 and executable on the processor 502. When the processor 502 executes the computer program, it implements the power battery state of charge estimation method as described above.

[0135] Among them, Figure 5 In this document, a bus architecture (represented by bus 500) is used. Bus 500 may include any number of interconnected buses and bridges, linking various circuits including one or more processors represented by processor 502 and memory represented by memory 504. Bus 500 may also link various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. Bus interface 505 provides an interface between bus 500 and receiver 501 and transmitter 503. Receiver 501 and transmitter 503 may be the same element, i.e., a transceiver, providing a unit for communicating with various other devices over a transmission medium. Processor 502 is responsible for managing bus 500 and general processing, while memory 504 can be used to store data used by processor 502 during operation.

[0136] Those skilled in the art will understand that Figure 5 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the power battery state of charge estimation device applied thereto. The specific power battery state of charge estimation device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0137] Based on the same inventive concept, embodiments of this application also provide a computer-readable storage medium storing a computer program thereon. When the computer program is executed by a processor, it performs the following steps: determining the current highest available capacity and the current lowest available capacity of the battery cell; determining the current health of the power battery; determining the current consistency deviation capacity based on the rated capacity of the power battery, the previous maximum value and the previous minimum value of the state of charge; determining the current maximum value and the current minimum value of the state of charge based on the current highest available capacity, the current lowest available capacity, the current health, and the current consistency deviation capacity; and determining the current true value of the state of charge based on the current maximum value and the current minimum value.

[0138] In some embodiments of this application, based on the foregoing scheme, when the computer program is executed by the processor, it further implements the following steps: obtaining the current consistency deviation capacity based on the rated capacity of the power battery, the previous maximum value, the previous minimum value, and the following formula: Q1 = Q R *(1-SOC max0 +SOC min0 ); where Q1 is the current consistency deviation capacity, Q R For rated capacity, SOC max0 SOC is the previous maximum value. min0 It is the previous minimum value.

[0139] In some embodiments of this application, based on the foregoing scheme, when the computer program is executed by the processor, it further implements the following steps: obtaining the current maximum value based on the current highest available capacity, the current health status, the current consistency deviation capacity, and the following formula:

[0140] Among them, SOC max1 Q is the current maximum value. max1 The highest available capacity is represented by SOH1, and the current health status is represented by SOH1. The current minimum value is obtained based on the lowest available capacity, current health status, current consistency deviation capacity, and the following formula:

[0141] Among them, SOC min1 Q is the current minimum value. min1 This represents the current minimum available capacity.

[0142] In some embodiments of this application, based on the foregoing scheme, when the computer program is executed by the processor, it further implements the following steps: obtaining the current true value based on the current maximum value, the current minimum value, and the following formula:

[0143] Among them, SOC real This is the current actual value.

[0144] In some embodiments of this application, based on the foregoing scheme, when the computer program is executed by the processor, it further implements the following steps: obtaining the previous maximum value, the previous minimum value, and the previous health status of the state of charge; determining the current maximum available capacity by multiplying the previous maximum value, the previous health status, and the rated capacity; and determining the current maximum available capacity by multiplying the previous minimum value, the previous health status, and the rated capacity.

[0145] In some embodiments of this application, based on the foregoing scheme, when the computer program is executed by the processor, it further implements the following steps: obtaining the current capacity change and the current state of charge change of the power battery; and obtaining the current health status based on the current capacity change, the current state of charge change, and the rated capacity.

[0146] In some embodiments of this application, based on the foregoing scheme, when the computer program is executed by the processor, it further implements the following steps: obtaining the current health status based on the current capacity change, the current state of charge change, the rated capacity, and the following formula:

[0147] Where SOH1 is the current health status, ΔQ1 is the current capacity change, ΔSOC1 is the current state of charge change, and Q... R This is the rated capacity.

[0148] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored as one or more instructions or codes on or transmitted via a computer-readable medium. Other examples and embodiments are within the scope and spirit of this application and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hardwired, or any combination thereof. Furthermore, the functional units may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit.

[0149] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0150] The units described as separate components may or may not be physically separate. Similarly, the components of the control device may or may not be physical units; they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0151] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or 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 a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard drive, magnetic disk, or optical disk.

[0152] The above description is merely an embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for estimating the state of charge of a power battery, characterized in that, The power battery includes multiple cells, and the method for estimating the state of charge of the power battery includes: Determine the current highest available capacity and the current lowest available capacity of the battery cell; Determine the current health status of the power battery; The current consistency deviation capacity is determined based on the rated capacity, the previous maximum value and the previous minimum value of the state of charge of the power battery. Based on the current highest available capacity, the current lowest available capacity, the current health status, and the current consistency deviation capacity, determine the current maximum and minimum values ​​of the state of charge; Based on the current maximum value and the current minimum value, determine the current true value of the state of charge; wherein, determining the current consistency deviation capacity based on the rated capacity of the power battery, the previous maximum value and the previous minimum value of the state of charge includes: The current consistency deviation capacity is obtained based on the rated capacity of the power battery, the previous maximum value, the previous minimum value, and the following formula: Q1=Q R (1-SOC max0 +SOC min0 ); Where Q1 is the current consistency deviation capacity, Q R For the rated capacity, SOC max0 For the previous maximum value, SOC min0 This is the previous minimum value; Determining the current true value of the state of charge based on the current maximum value and the current minimum value includes: The current true value is obtained based on the current maximum value, the current minimum value, and the following formula: ； Among them, SOC real For the current true value, SOC max1 For the current maximum value, SOC min1 This is the current minimum value.

2. The method for estimating the state of charge of a power battery according to claim 1, characterized in that, The step of determining the current maximum and minimum values ​​of the state of charge based on the current highest available capacity, the current lowest available capacity, the current health status, and the current consistency deviation capacity includes: The current maximum value is obtained based on the current highest available capacity, the current health status, the current consistency deviation capacity, and the following formula: ； Among them, Q max1 The highest available capacity is defined as SOH1, and the current health status is defined as SOH1. The current minimum value is obtained based on the current minimum available capacity, the current health status, the current consistency deviation capacity, and the following formula: ； Among them, Q min1 This represents the current minimum available capacity.

3. The method for estimating the state of charge of a power battery according to any one of claims 1 to 2, characterized in that, Determining the current highest available capacity and the current lowest available capacity of the battery cell includes: Obtain the previous maximum value, previous minimum value, and previous health status of the charge state; The product of the previous maximum value, the previous health status, and the rated capacity is determined as the current highest available capacity; The product of the previous minimum value, the previous health status, and the rated capacity is determined as the current minimum available capacity.

4. The method for estimating the state of charge of a power battery according to claim 3, characterized in that, Determining the current health status of the power battery includes: Obtain the current capacity change and the current state of charge change of the power battery; The current health status is obtained based on the current capacity change, the current state of charge change, and the rated capacity.

5. The method for estimating the state of charge of a power battery according to claim 4, characterized in that, The process of obtaining the current health status based on the current capacity change, the current state of charge change, and the rated capacity includes: The current health status is obtained based on the current capacity change, the current state of charge change, the rated capacity, and the following formula: ； Wherein, SOH1 represents the current health status. The current capacity change is... Q is the change in the current state of charge. R The rated capacity is [the specified capacity].

6. A device for estimating the state of charge of a power battery, characterized in that, The power battery includes multiple cells, and the power battery state-of-charge estimation device includes: A capacity determination unit is used to determine the current highest available capacity and the current lowest available capacity of the battery cell; A health determination unit is used to determine the current health status of the power battery; The capacity deviation unit is used to determine the current consistency deviation capacity based on the rated capacity, the previous maximum value and the previous minimum value of the state of charge of the power battery. The SOC extreme value determination unit is used to determine the current maximum and minimum values ​​of the state of charge based on the current highest available capacity, the current lowest available capacity, the current health status, and the current consistency deviation capacity. The SOC true value determination unit is used to determine the current true value of the state of charge based on the current maximum value and the current minimum value. The capacity deviation unit is further configured to obtain the current consistency deviation capacity based on the rated capacity of the power battery, the previous maximum value, the previous minimum value, and the following formula: Q1=Q R (1-SOC max0 +SOC min0 ); Where Q1 is the current consistency deviation capacity, Q R For the rated capacity, SOC max0 For the previous maximum value, SOC min0 This is the previous minimum value; The SOC true value determination unit is further configured to obtain the current true value based on the current maximum value, the current minimum value, and the following formula: ； Among them, SOC real For the current true value, SOC max1 For the current maximum value, SOC min1 This is the current minimum value.

7. A device for estimating the state of charge of a power battery, comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 5.

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