Method, device, equipment, and storage medium for determining battery health status

Abstract

The embodiments of the present application disclose a method for determining the health status of a battery, as well as an apparatus, device, and storage medium. The method includes: determining the charge and discharge curve of a target battery, and adjusting the curve parameters of the charge and discharge curve to obtain an adjusted charge and discharge curve; when the degree of fit between the curve parameter charge and discharge curve and the initial reference curve reaches a preset threshold, determining the current value of the curve parameter based on the adjustment amount of the curve parameter and the initial value of the curve parameter; determining a battery status characterization index of the curve parameter target battery based on the current value of the curve parameter; and determining the health status of the curve parameter target battery based on the battery status characterization index of the curve parameter target battery. The actual value of each battery parameter can be obtained, which improves the accuracy of the acquired battery parameters and further allows for more accurate determination of the health status of the battery.

Description

Technical Field

[0001] The embodiments of the present application relate to battery analysis technology, and are related to, but not limited to, a method for determining the health status of a battery and its apparatus, device, and storage medium. Background Art

[0002] After a period of use, the battery will experience loss of electrode materials. To determine the health status of the battery, it is necessary to obtain battery parameters and determine the battery health status based on the battery parameters.

[0003] In related technologies, the technical means used to determine battery parameters usually involves disassembling battery cells to determine the proportions of various electrode materials, but the specific values ​​cannot be determined. Therefore, the obtained battery parameters are not comprehensive and have low accuracy, which results in the inability to accurately obtain the battery's health status. Summary of the Invention

[0004] In view of this, the battery health status determination method, apparatus, device, and storage medium provided in the embodiments of the present application can obtain the actual values ​​of each battery parameter, improve the accuracy of the obtained battery parameters, and further more accurately determine the battery health status. The battery health status determination method, apparatus, device, and storage medium provided in the embodiments of the present application are implemented as follows:

[0005] An embodiment of the present application provides a method for determining a battery health status, the method comprising:

[0006] Determine the charge and discharge curve of the target battery, and adjust the curve parameters of the charge and discharge curve to obtain an adjusted charge and discharge curve, wherein the curve parameters are used to change the shape of the curve parameter charge and discharge curve, and the curve parameters include: parameters of irreversible loss of the curve parameter target battery that causes capacity change;

[0007] When the degree of fit between the curve parameter charge and discharge curve and the initial reference curve reaches a preset threshold, the current value of the curve parameter is determined according to the adjustment amount of the curve parameter and the initial value of the curve parameter. The initial reference curve of the curve parameter is a charge and discharge curve obtained by performing a charge and discharge test when the target battery of the curve parameter has no loss. The initial value of the curve parameter is the value of the curve parameter in the initial reference curve of the curve parameter;

[0008] Determine a battery status characterization indicator of a target battery of the curve parameter according to the current value of the curve parameter;

[0009] The health state of the curve parameter target battery is determined according to a battery state characterization index of the curve parameter target battery.

[0010] The battery health status determination device provided in an embodiment of the present application includes: a curve adjustment module, a value determination module, a result calculation module, and a status determination module;

[0011] A curve adjustment module is used to determine the charge and discharge curve of the target battery and adjust the curve parameters of the charge and discharge curve to obtain an adjusted charge and discharge curve. The curve parameters are used to change the shape of the charge and discharge curve. The curve parameters include: parameters of irreversible loss caused by capacity change of the target battery;

[0012] a value determination module for determining the current value of the curve parameter based on the adjustment amount of the curve parameter and the initial value of the curve parameter when the degree of fit between the charge and discharge curve and the initial reference curve reaches a preset threshold, wherein the initial reference curve is a charge and discharge curve obtained by performing a charge and discharge test when the target battery has no loss, and the initial value of the curve parameter is the value of the curve parameter in the initial reference curve;

[0013] A result calculation module is used to determine the battery status characterization index of the target battery according to the current value of the curve parameter;

[0014] The state determination module is used to determine the health state of the target battery according to the battery state characterization index of the target battery.

[0015] The computer device provided in the embodiment of the present application includes a memory and a processor. The memory stores a computer program that can be run on the processor. When the processor executes the program, the method of the embodiment of the present application is implemented.

[0016] The computer-readable storage medium provided in the embodiment of the present application stores a computer program thereon, and when the computer program is executed by a processor, the method provided in the embodiment of the present application is implemented.

[0017] The battery health status determination method, apparatus, device, and storage medium provided in the embodiments of the present application can determine the charge and discharge curve of the target battery; and then adjust the curve parameters of the charge and discharge curve to obtain the adjusted charge and discharge curve. When the degree of fit between the charge and discharge curve and the initial reference curve reaches a preset threshold, the current value of the curve parameter is determined according to the adjustment amount of the curve parameter and the initial value of the curve parameter. The battery status characterization index of the target battery is determined according to the current value of the curve parameter; the health status of the target battery is determined according to the battery status characterization index of the target battery. Among them, the current value of the curve parameter can be obtained by fitting the charge and discharge curve, that is, the actual value of each battery parameter can be estimated, and the accuracy of the actual value of the determined battery parameter can also be improved by fitting the charge and discharge curve. Accordingly, the health status of the target battery can be obtained more accurately. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present application and, together with the specification, are used to illustrate the technical solutions of the present application.

[0019] Figure 1 A flowchart of a method for determining a battery health status provided in an embodiment of the present application;

[0020] Figure 2 This is another flowchart of the method for determining the battery health status provided in an embodiment of the present application;

[0021] Figure 3 This is a curve adjustment diagram provided in an embodiment of the present application;

[0022] Figure 4 This is another curve adjustment schematic diagram provided in an embodiment of the present application;

[0023] Figure 5 This is another curve adjustment schematic diagram provided in an embodiment of the present application;

[0024] Figure 6 This is another curve adjustment schematic diagram provided in an embodiment of the present application;

[0025] Figure 7 This is another curve adjustment schematic diagram provided in an embodiment of the present application;

[0026] Figure 8 This is another curve adjustment schematic diagram provided in an embodiment of the present application;

[0027] Figure 9 This is another flowchart of the method for determining the battery health status provided in an embodiment of the present application;

[0028] Figure 10 A schematic diagram of the structure of a device for determining a battery health status provided in an embodiment of the present application;

[0029] Figure 11 This is a schematic diagram of the structure of the computer device provided in the embodiment of the present application. DETAILED DESCRIPTION

[0030] To make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the specific technical solutions of the present application will be further described in detail below in conjunction with the drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application but are not intended to limit the scope of the present application.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein are for the purpose of describing the embodiments of this application only and are not intended to limit this application.

[0032] In the following description, reference is made to “some embodiments”, which describes a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0033] It should be pointed out that the terms "first\second\third" involved in the embodiments of the present application are used to distinguish similar or different objects, and do not represent a specific ordering of the objects. It can be understood that "first\second\third" can be interchanged with a specific order or sequence where permitted, so that the embodiments of the present application described here can be implemented in an order other than that illustrated or described here.

[0034] It should be noted that after a period of use, the battery will experience loss of electrode material. In order to determine the loss of the battery, it is necessary to obtain battery parameters.

[0035] In related technologies, methods for obtaining battery parameters mainly include the following methods:

[0036] (1) Determine the corresponding battery parameters by comparing the current charge and discharge curve of the battery with the charge and discharge curve in the initial state. This method can only calculate the capacity change value of the battery cell during the charge and discharge process, but cannot obtain other battery parameters, which means that the battery parameters obtained are too few.

[0037] (2) By performing a low-rate charge and discharge experiment on the battery cell, the reversible capacity and irreversible capacity loss of the cell in the current state can be calculated. This method can calculate more battery parameters, such as the proportion of reversible capacity loss parameters and irreversible capacity loss parameters, but it cannot determine the specific source of each loss in the reversible capacity loss parameters. Therefore, the parameters obtained are also somewhat one-sided.

[0038] (3) By performing differential processing on the charge and discharge curves of the battery cell cycle process, a differential capacity or differential voltage curve is obtained, and based on the changes in the characteristic values ​​of the curve, such as the peak position, peak position, peak area, and half-peak width, the specific source of each loss is qualitatively determined. Although this method can qualitatively attribute the source of capacity loss based on various peak characteristics, since the calculation involves differential processing, the algorithm for data differential processing (such as the number of points and the method of taking points) will have a great impact on the results when the loss is small, and may even cause completely opposite results, thereby affecting the analysis of the experimental results. In other words, the accuracy of the battery parameters obtained by the differential method is low.

[0039] (4) By disassembling the battery, the quantitative analysis of the elements in the cell and the positive and negative electrodes is obtained, thereby roughly calculating the battery balance value and other battery parameters. This method can only obtain the total proportion of each element through quantitative analysis of the elements after disassembling the cell, and cannot confirm the actual content of each positive and negative electrode. Therefore, the calculated battery balance value has a certain error, which means that the accuracy of the obtained battery parameters is poor.

[0040] In view of this, the technical means provided in the related art will result in a limited number of battery parameter types, which is somewhat one-sided and has the problem of low accuracy. In order to solve the above problems existing in the prior art, the embodiment of the present application provides a method for determining the health status of the battery. The implementation process of this method is explained in detail below.

[0041] Figure 1 For a flow chart of the method for determining the battery health status provided in the embodiment of the present application, please refer to Figure 1 , the method comprising:

[0042] S110: Determine a charge and discharge curve of the target battery, and adjust curve parameters of the charge and discharge curve to obtain an adjusted charge and discharge curve.

[0043] Optionally, the method may be performed by a computer device, which may include but is not limited to a mobile phone, a wearable device (such as a smart watch, a smart bracelet, smart glasses, etc.), a tablet computer, a laptop computer, a vehicle-mounted terminal, a PC (Personal Computer), etc. The functions implemented by the method may be implemented by a processor in the computer device calling program code. Of course, the program code may be stored in a computer storage medium. Therefore, the computer device includes at least a processor and a storage medium.

[0044] It should be noted that the target battery can be any battery for which the corresponding curve parameters need to be determined. The specific model and usage time of the battery are not limited. For example, it can be a mobile phone battery, a dry cell battery, an energy storage battery, etc., and no specific restrictions are made here.

[0045] The charge-discharge curve may be, for example, a curve showing changes in the voltage of the battery as the amount of charge in the battery changes.

[0046] The charge and discharge curve of the battery can be determined in the following way:

[0047] The positive and negative electrode charge and discharge curves in the initial state are determined based on the battery cell design information when the battery leaves the factory, for example, the initial balance value CB (Cell Balance) of the battery cell. After obtaining the positive and negative electrode charge and discharge curves respectively, the negative electrode charge and discharge curve can be subtracted from the positive electrode charge and discharge curve to obtain the target battery's charge and discharge curve. This charge and discharge curve represents the relationship between charge and voltage changes when the target battery is actually operating in its current state.

[0048] The curve parameters are used to change the shape of the charge-discharge curve. The curve parameters include parameters for irreversible loss of capacity of the target battery.

[0049] It should be noted that the charge-discharge curve can be adjusted by fitting the charge-discharge curve with the initial reference curve. Specifically, the curve parameters of the charge-discharge curve can be adjusted to achieve the fitting of the charge-discharge curve with the initial reference curve.

[0050] The initial reference curve may be a charge-discharge curve obtained by performing a charge-discharge test when the target battery has no loss.

[0051] For example, a coin cell with the same positive and negative electrode materials can be prepared based on the chemical system corresponding to the target battery's cell, and the coin cell can be charged and discharged at a specified rate to obtain a charge-discharge curve. This charge-discharge curve is the initial reference curve, which can be a curve that represents the relationship between charge and voltage change of the target battery without any loss.

[0052] For example, in the process of determining the initial reference curve, it can be determined as follows:

[0053] The target battery may be a lithium iron phosphate battery, for example, a battery having a charge and discharge rate of 1C and a low-rate recovery test rate of 0.025C.

[0054] First, prepare the positive and negative electrode slurries: For the positive electrode, weigh approximately 5g of powder using a ratio of lithium iron phosphate: conductive carbon: binder of approximately 90:5:5. For the negative electrode, weigh approximately 5g of powder using a ratio of graphite: conductive carbon: binder of approximately 92:2:6. Stir the powder in a centrifuge at 1500-2000rpm for 10-20min. Then, apply the uniformly stirred slurry to a coater using a scraper with a 200µm gap. The electrode pieces can then be vacuum-dried at 90-110°C. The dried electrode pieces can then be cut and weighed. The cut electrode pieces can then be fabricated into button cells in the order of casing / electrode piece / diaphragm / lithium sheet / casing. Finally, charge and discharge tests can be performed on the assembled positive and negative electrode button cells at a rate of 0.025C to generate charge and discharge curves, which serve as the initial reference curves.

[0055] It should be noted that the curve parameter may be a parameter of irreversible loss of capacity change of the target battery, or may be other parameters that affect the shape of the charge and discharge curve of the target battery, and is not specifically limited here.

[0056] Optionally, when the curve parameters are different, the shape of the charge and discharge curve of the target battery will change; the shape of the charge and discharge curve of the target battery can be changed by adjusting one or more parameters of the curve parameters of the target battery so that the charge and discharge curve of the target battery fits the initial reference curve.

[0057] S120: When the degree of fit between the charge-discharge curve and the initial reference curve reaches a preset threshold, a current value of the curve parameter is determined according to the adjustment amount of the curve parameter and the initial value of the curve parameter.

[0058] The initial values ​​of the curve parameters are the values ​​of the curve parameters in the initial reference curve.

[0059] Optionally, a preset threshold can be pre-configured, which represents the error range of the initial reference curve. When the degree of fit between the charge and discharge curve and the initial reference curve reaches the preset threshold, it can be determined that the charge and discharge curve has been adjusted to the charge and discharge curve in the factory state; if the degree of fit does not reach the preset threshold, the curve parameters can continue to be adjusted until the degree of fit between the charge and discharge curve and the initial reference curve reaches the preset threshold.

[0060] It should be noted that the initial values ​​of the various curve parameters in the initial reference curve can be known quantities. For example, the parameters of the irreversible loss of capacity of the target battery when the target battery is in the factory state can all be 0, or can be other known values, and no specific restrictions are given here.

[0061] During the above adjustment process, an adjustment amount of the curve parameter may be determined, where the adjustment amount represents a change in the charge-discharge curve from an initial position to a position where the degree of fit reaches a preset threshold.

[0062] Optionally, the current value of the curve parameter can be determined based on the adjustment amount of the curve parameter and the initial value of the curve parameter.

[0063] For example, the value of the curve parameter can be obtained by subtracting the adjustment amount from the initial value of the curve parameter.

[0064] For example, if the adjustment amount of the curve parameter is -2 units and the initial value of the curve parameter is 0, it can be determined that the current value of the curve parameter is 2 units.

[0065] Optionally, during the actual adjustment process, adjustments to multiple parameters may be involved. The adjustment amount and initial value of each parameter may be determined in the above manner to further calculate the current value of the curve parameter.

[0066] S130: Determine a battery status characterization indicator of the target battery according to the current value of the curve parameter.

[0067] It should be noted that after obtaining the current value of each curve parameter in the above manner, the battery state characterization index of the target battery can be calculated based on the corresponding curve parameter.

[0068] Optionally, the battery status indicator of the target battery may refer to the balance value of the target battery, that is, the CB value of the target battery in the current state, that is, the ratio of the negative electrode capacity to the positive electrode capacity on the front side of the battery in the current state.

[0069] In one embodiment, the curve parameters also include: an offset of the charge and discharge curve after active lithium loss occurs in the battery film formation; determining the battery state characterization index of the target battery based on the current value of the curve parameter, including: determining the balance value of the target battery cell after active lithium loss occurs in the battery film formation based on the offset of the charge and discharge curve after active lithium loss occurs in the battery film formation and the initial balance value of the target battery cell; determining the balance value of the target battery based on the balance value of the target battery cell after active lithium loss occurs in the battery film formation and the parameters of irreversible loss of capacity change in the target battery.

[0070] The charge-discharge curve offset after active lithium loss occurs in the battery film formation can be the value of one of the parameters obtained by determining the current value of the above-mentioned curve parameter. The initial balance value of the target battery cell can be the balance value of the target battery cell when it leaves the factory. Specifically, the balance value of the target battery cell after active lithium loss occurs in the battery film formation can be calculated by the following formula:

[0071] LR ini=(100%-OFS ini ) / (100%)*LR0;

[0072] Among them, OFS ini is the charge-discharge curve offset after active lithium loss occurs in the battery film; LR0 is the initial balance value of the target battery cell; LR ini It is the equilibrium value of the cell after active lithium loss occurs in the target battery film.

[0073] After calculating the balance value of the battery cell after active lithium loss occurs in the target battery film formation in the above manner, the balance value of the target battery can be calculated based on the balance value of the battery cell after active lithium loss occurs in the target battery film formation and the parameters of the irreversible loss of capacity change in the target battery.

[0074] Optionally, in one embodiment, the parameters of irreversible loss of capacity change of the target battery include: active lithium loss parameter, positive electrode active material lithium insertion loss parameter, positive electrode active material lithium delithiation loss parameter, negative electrode active material lithium insertion loss parameter and negative electrode active material lithium delithiation loss parameter.

[0075] In the process of calculating the target battery balance value, the positive electrode active material lithium insertion loss parameter, the positive electrode active material lithium removal loss parameter, the negative electrode active material lithium insertion loss parameter, and the negative electrode active material lithium removal loss parameter may be used.

[0076] The specific formula is as follows:

[0077] LR=LR ini (100%-%LAM deNE -%LAM liNE ) / (100%-%LAM dePE -%LAM liPE );

[0078] Among them, LAM liPE LAM is the lithium insertion loss parameter of the positive electrode active material; dePE LAM is the lithium loss parameter of the positive electrode active material; liNE LAM is the lithium insertion loss parameter of the negative electrode active material; deNE is the lithium loss parameter of the negative electrode active material; LR is the balance value of the target battery.

[0079] S140: Determine the health status of the target battery according to the battery status characterization indicator of the target battery.

[0080] It should be noted that after obtaining the battery status characterization index of the target battery in the above manner, the health status of the target battery can be determined based on the battery status characterization index of the target battery, that is, the health status of the target battery is determined based on the CB value of the target battery.

[0081] The specific method is as follows:

[0082] (1) If the CB value continues to increase with the number of cycles during the steady-state decay phase of the battery cell, it means that the decay rate of the positive electrode material in the battery cell is faster;

[0083] (2) If the CB value remains stable as the number of cycles increases during the stable decay stage of the battery cell, it means that the decay rates of the positive and negative electrodes in the battery cell are basically consistent;

[0084] (3) If the CB value decreases with the increase of the number of cycles in the stable decay stage of the battery cell, it means that the negative electrode decay rate in the battery cell is faster;

[0085] (4) If the CB value is less than 1 during the cycle, it indicates that the battery cell is currently at risk of lithium plating.

[0086] In addition to determining the health status of the battery by determining the CB value of the battery, determining other curve parameters can also be stored as reference data for subsequent production and technological breakthroughs of the battery, or corresponding curve parameters can be used based on the actual work to be performed, without specific restrictions here.

[0087] In the method for determining the battery health status provided in the embodiment of the present application, the charge and discharge curve of the target battery can be determined; then, the curve parameters of the charge and discharge curve are adjusted to obtain the adjusted charge and discharge curve. When the degree of fit between the charge and discharge curve and the initial reference curve reaches a preset threshold, the current value of the curve parameter is determined based on the adjustment amount of the curve parameter and the initial value of the curve parameter. Based on the current value of the curve parameter, the battery status characterization index of the target battery is determined; and the health status of the target battery is determined based on the battery status characterization index of the target battery. Among them, the current value of the curve parameter can be obtained by fitting the charge and discharge curve, that is, the actual value of each battery parameter can be estimated, and the accuracy of the actual value of the determined battery parameter can also be improved by fitting the charge and discharge curve. Accordingly, the health status of the target battery can be obtained more accurately.

[0088] The following explains another specific implementation process of the method for determining the battery health status provided in an embodiment of the present application.

[0089] Figure 2 This is another flowchart of the method for determining the battery health status provided in the embodiment of the present application. Please refer to Figure 2 , adjust the curve parameters of the charge and discharge curve to obtain the adjusted charge and discharge curve, including:

[0090] S210: Adjust each first curve parameter of the charge-discharge curve to obtain an adjusted charge-discharge curve.

[0091] The first curve parameter is any one of the multiple curve parameters.

[0092] It should be noted that, during the actual adjustment process, multiple parameters in the charge and discharge curve can be adjusted. These parameters may include, for example, any one of the multiple curve parameters, that is, the parameter of the irreversible loss of capacity change of the above-mentioned target battery, or other parameters that affect the shape of the charge and discharge curve of the target battery.

[0093] It should be noted that, in the process of adjusting the curve, the relationship between the various parameters in the curve can be determined, for example, it can be expressed according to the following two formulas:

[0094] SOC NE =(100%-SOC PE )*LR ini +OFS ini ;

[0095] OFS=OFS ini +LR*%LAM liNE +LR / LR ini *%LAM dePE +%LLI ch -%LLI dis ;

[0096] Among them, SOC NE Indicates the state of charge of the negative electrode of the target battery; SOC PE Indicates the charge state of the positive electrode of the target battery; OFS indicates the offset of the charge and discharge curve of the target battery due to the presence of five active substances; LLI ch and LLI dis is the active lithium loss parameter, also known as the LLI parameter, where LLI ch is the active lithium loss parameter during charging, LLI dis is the active lithium loss parameter during discharge.

[0097] In the process of adjusting the curve parameters, the above two formulas can be referred to to determine the changes in other parameters according to the changes in the corresponding parameters, thereby obtaining the adjusted charge and discharge curve.

[0098] Among them, the shape of the charge and discharge curve can be adjusted by multiple curve parameters. For example, LR and OFS can be adjusted. ini 、LLI、LAM deNE and LAM liPE Five parameters are used to adjust the shape of the charge and discharge curve.

[0099] When the degree of fit between the charge and discharge curve and the initial reference curve reaches a preset threshold, the current value of the curve parameter is determined according to the adjustment amount of the curve parameter and the initial value of the curve parameter, including:

[0100] S220: When the first curve parameter changes and other curve parameters except the first curve parameter remain unchanged, and the fit between the charge and discharge curve and the initial reference curve reaches a preset threshold, determine a first value of the first curve parameter according to the adjustment amount of the first curve parameter and the initial value of the first curve parameter.

[0101] Optionally, any curve parameter can be used as the first curve parameter, and the first curve parameter can be adjusted while keeping other curve parameters unchanged to determine the first value of the first curve parameter. In this way, the first value of each first curve parameter can be determined separately.

[0102] For example: you can make OFS ini 、LLI、LAM deNE and LAM liPE The four parameters remain unchanged, and LR (the balance value of the target battery) is adjusted to determine the change in the position of the charge-discharge curve under different LR values. Then, when the fit between the charge-discharge curve and the initial reference curve reaches the preset threshold, the adjustment amount and initial value of LR are determined, thereby calculating the first value of LR. ini 、LLI、LAM deNE and LAM liPE The first value of the five parameters.

[0103] S230: Determine current values ​​of the respective curve parameters based on the first values ​​of the respective first curve parameters.

[0104] It should be noted that after obtaining the first value of each first curve parameter, the current value of each curve parameter in this case can be determined. For example, the first value can be directly used as the current value, or further adjusted more accurately, and the adjusted value can be used as the current value. No specific restrictions are imposed here.

[0105] In the method for determining the battery health status provided in the embodiment of the present application, each first curve parameter of the charge and discharge curve can be adjusted to obtain an adjusted charge and discharge curve. When the first curve parameter changes and other curve parameters except the first curve parameter remain unchanged, and the fit between the charge and discharge curve and the initial reference curve reaches a preset threshold, the first value of the first curve parameter is determined based on the adjustment amount of the first curve parameter and the initial value of the first curve parameter. Based on the first value of each first curve parameter, the current value of each curve parameter is determined. By adjusting each parameter separately, the value of each curve parameter can be determined when the fit of the charge and discharge curve is most appropriate, thereby improving the accuracy of the actual value of the determined battery parameter.

[0106] In order to explain the embodiments of the present application in more detail, the following describes the changes in the charge-discharge curves when each of the five parameters mentioned above is changed individually.

[0107] First, let's explain how the charge and discharge curves change when LR changes and other parameters remain unchanged:

[0108] Figure 3 For the curve adjustment diagram provided in the embodiment of this application, please refer to Figure 3 , Figure 3 The content shown is the change of the charge and discharge curve after LR is changed when LR ≤ 1.

[0109] in, Figure 3 The charge and discharge curves of six cases, LR=0.5, LR=0.6, LR=0.7, LR=0.8, LR=0.9, and LR=1.0, are shown in Figure 1. The blue curve shows the battery voltage changing with the charge amount when LR=0.5; the orange curve shows the battery voltage changing with the charge amount when LR=0.6; the green curve shows the battery voltage changing with the charge amount when LR=0.7; the red curve shows the battery voltage changing with the charge amount when LR=0.8; the purple curve shows the battery voltage changing with the charge amount when LR=0.9; and the brown curve shows the battery voltage changing with the charge amount when LR=1.0.

[0110] Figure 3 In the graph, the horizontal axis represents the percentage of charge change, and the vertical axis represents the value of voltage change.

[0111] When LR changes and other parameters remain unchanged, the charge and discharge curves may show another change as follows:

[0112] Figure 4 For another curve adjustment diagram provided in the embodiment of this application, please refer to Figure 4 , Figure 4 The content shown is the change of charge and discharge curve after LR changes when LR ≥ 1.

[0113] in, Figure 4 The charge and discharge curves of six cases, LR=1.0, LR=1.1, LR=1.2, LR=1.3, LR=1.4, and LR=1.5, are shown in Figure 1. The blue curve shows the battery voltage changing with the charge amount when LR=1.0; the orange curve shows the battery voltage changing with the charge amount when LR=1.1; the green curve shows the battery voltage changing with the charge amount when LR=1.2; the red curve shows the battery voltage changing with the charge amount when LR=1.3; the purple curve shows the battery voltage changing with the charge amount when LR=1.4; and the brown curve shows the battery voltage changing with the charge amount when LR=1.5.

[0114] Figure 4 In the graph, the horizontal axis represents the percentage of charge change, and the vertical axis represents the value of voltage change.

[0115] Next, explain in OFS ini When the other parameters remain unchanged, the change of charge and discharge curve is as follows:

[0116] Figure 5 For another curve adjustment diagram provided in the embodiment of this application, please refer to Figure 5 , Figure 5 The content shown is for the case of LR=1.04, in OFS ini Changes in the charge and discharge curves after the change.

[0117] in, Figure 5 OFS is exemplified in ini =0, OFS ini =2, OFS ini =4, OFS ini =6, OFS ini =8, OFS ini =10 Charge and discharge curves under six conditions and the initial reference curve, where the blue curve is OFS ini =0, the battery voltage changes with the charge amount; the orange curve is OFS ini =2, the battery voltage changes with the charge amount; the green curve is OFS ini =4, the battery voltage changes with the charge amount; the red curve is OFS ini =6, the battery voltage changes with the charge amount; the purple curve is OFS ini=8, the battery voltage changes with the charge amount curve; the brown curve is OFS ini =10, the curve of the battery voltage changing with the charge amount; the black curve is the initial reference curve.

[0118] Figure 5 In the graph, the horizontal axis represents the percentage of charge change, and the vertical axis represents the value of voltage change.

[0119] Next, we will explain how the charge and discharge curves change when LLI changes and other parameters remain unchanged:

[0120] Figure 6 For another curve adjustment diagram provided in the embodiment of this application, please refer to Figure 6 , Figure 6 The content shown is the change of the charge and discharge curve after the LLI is changed when LR=1.04.

[0121] in, Figure 6 The figure shows the charge and discharge curves under six conditions: LLI = 0, LLI = 3, LLI = 6, LLI = 9, LLI = 12, and LLI = 15, as well as the initial reference curve. The blue curve shows the battery voltage changing with the charge amount when LLI = 0; the orange curve shows the battery voltage changing with the charge amount when LLI = 3; the green curve shows the battery voltage changing with the charge amount when LLI = 6; the red curve shows the battery voltage changing with the charge amount when LLI = 9; the purple curve shows the battery voltage changing with the charge amount when LLI = 12; the brown curve shows the battery voltage changing with the charge amount when LLI = 15; and the black curve is the initial reference curve.

[0122] Figure 6 In the graph, the horizontal axis represents the percentage of charge change, and the vertical axis represents the value of voltage change.

[0123] Next, let’s explain in LAM deNE When the other parameters remain unchanged, the change of charge and discharge curve is as follows:

[0124] Figure 7 For another curve adjustment diagram provided in the embodiment of this application, please refer to Figure 7 , Figure 7 The content shown is for the case of LR=1.04, in LAM deNE Changes in the charge and discharge curves after the change.

[0125] in, Figure 7 LAM is exemplified in deNE =1, LAM deNE =2, LAMdeNE =3, LAM deNE =4, LAM deNE =5, LAM deNE =6 Charge and discharge curves under six conditions and the initial reference curve, where the blue curve is LAM deNE =1, the battery voltage changes with the charge amount; the orange curve is LAM deNE =2, the battery voltage changes with the charge amount; the green curve is LAM deNE =3, the battery voltage changes with the charge amount; the red curve is LAM deNE =4, the battery voltage changes with the charge amount; the purple curve is LAM deNE =5, the battery voltage changes with the charge amount curve; the brown curve is LAM deNE =6, the curve of the battery voltage changing with the charge amount; the black curve is the initial reference curve.

[0126] It should be noted that according to Figure 7 The degree of overlap of the curves in LAM can be obtained deNE The change has little impact on the charge and discharge curves.

[0127] Next, let’s explain in LAM liPE When the other parameters remain unchanged, the change of charge and discharge curve is as follows:

[0128] Figure 8 For another curve adjustment diagram provided in the embodiment of this application, please refer to Figure 8 , Figure 8 The content shown is for the case of LR=1.04, in LAM liPE Changes in the charge and discharge curves after the change.

[0129] in, Figure 8 LAM is exemplified in liPE =1, LAM liPE =2, LAM liPE =3, LAM liPE =4, LAM liPE =5Charge and discharge curves under five conditions and the initial reference curve, where the blue curve is LAM liPE =1, the battery voltage changes with the charge amount; the orange curve is LAM liPE =2, the battery voltage changes with the charge amount; the green curve is LAM liPE =3, the battery voltage changes with the charge amount; the red curve is LAM liPE=4, the battery voltage changes with the charge amount; the purple curve is LAM liPE =5, the curve of the battery voltage changing with the charge amount; the black curve is the initial reference curve.

[0130] It should be noted that according to Figure 8 The degree of overlap of the curves in LAM can be obtained liPE The change has little impact on the charge and discharge curves. By zooming in on some locations, we can get the actual impact on the curves.

[0131] Optionally, determining the current value of each curve parameter based on the first value of each first curve parameter includes: using the first value of each first curve parameter as the current value of the curve parameter.

[0132] It should be noted that after performing the above adjustment on each first curve parameter to obtain a first value, the first value of each first curve parameter can be used as the current value of the curve parameter.

[0133] In the fitting process, the first value of LR is 1.04, the first value of LLI is 12%, and the first value of LAM is 1.04. dePE and LAM liNE The first value of is about 0, which can be relatively obtained by LAM liPE The first value is 0.4%, LAM deNE The first value of is 5%.

[0134] Optionally, the first value may be directly used as the current value of the curve parameter, or further adjustment may be performed to improve accuracy.

[0135] Optionally, based on the first values ​​of the respective first curve parameters, the current values ​​of the respective curve parameters are determined, including: based on the first values ​​of the respective first curve parameters, determining the corresponding charge and discharge curves under the respective first values; adjusting the respective first curve parameters within a preset range threshold, and determining the second values ​​of the first curve parameters when the degree of fit between the charge and discharge curves and the initial reference curve reaches a second preset threshold; and using the second values ​​of the respective first curve parameters as the current values ​​of the curve parameters.

[0136] It should be noted that a charge and discharge curve can be determined by the first values ​​of the above-mentioned first curve parameters, and the charge and discharge curve can be fine-tuned in a small range. For example, the shape of the charge and discharge curve can be changed by increasing or decreasing each curve parameter within a preset range threshold. When the fit between the charge and discharge curve and the initial reference curve reaches a second preset threshold, a second value of the first curve parameter can be obtained by a calculation method similar to the above. The second value is more accurate than the first value, and the second value of each first curve parameter can be used as the current value of the curve parameter.

[0137] For example, the second value of LR is 1.04, the second value of LLI is 12.6%, and the second value of LAM is 1.04. dePE and LAM liNE The second value of is approximately 0, and LAM can be obtained relatively liPE The second value is 0.47%, LAM deNE The second value is 5.4%, and it can be seen that the error between this case and the initial reference curve is 5.8%.

[0138] It should be noted that the above-mentioned method of adjusting the charge-discharge curve and obtaining the current value of the curve parameter is only one feasible method. In addition to the above-mentioned method, other methods can also be used to achieve the above-mentioned result, as follows:

[0139] Figure 9 This is another flowchart of the method for determining the battery health status provided in the embodiment of the present application. Please refer to Figure 9 When the degree of fit between the charge-discharge curve and the initial reference curve reaches the highest, the parameter values ​​of the adjustment parameters corresponding to the charge-discharge curve are determined, including:

[0140] S910: Determine a second curve parameter to be adjusted for the deviation position among the curve parameters according to the deviation position between the charge and discharge curve and the initial reference curve and the mapping relationship between each curve parameter and the deviation position.

[0141] It should be noted that when the various adjustment parameters change, different effects may be produced on the charge and discharge curves. For example, Figure 3-Figure 4 It can be seen that adjusting LR can affect the expansion and contraction of the horizontal axis of the entire charge and discharge curve; Figure 5 Can be obtained, adjust OFS ini Can affect the lateral translation of the negative electrode curve of the charge and discharge curve; combined with the reference to the above Figure 6 It can be seen that adjusting LLI can affect the lateral movement of the negative electrode curve of the charge and discharge curve; combined with the reference to the above Figure 7 Can be obtained, adjust LAM deNEIt can affect the contraction of the negative high charge region of the charge and discharge curve; combined with the above Figure 8 Can be obtained, adjust LAM liPE It can affect the contraction of the positive electrode high charge region of the charge and discharge curve.

[0142] The above-mentioned influencing position can have a mapping relationship between the curve parameters and the deviation position. For example, when the contraction of the positive high charge area needs to be adjusted, the LAM can be adjusted. liPE This curve parameter.

[0143] The position affected by each curve parameter can be pre-configured, that is, the mapping relationship between the curve parameter and the deviation position can be configured, and then the second curve parameter adjusted for the deviation position in the curve parameter is determined according to the deviation position between the charge and discharge curve and the initial reference curve.

[0144] For example, if the deviation position between the charge-discharge curve and the initial reference curve is the expansion and contraction situation on the horizontal axis of the entire curve, the second curve parameter can be determined to be LR.

[0145] S920: When the second curve parameter changes and other curve parameters except the second curve parameter remain unchanged, and the fit between the charge and discharge curve and the initial reference curve reaches a preset threshold, determine the current value of each curve parameter according to the adjustment amount of the second curve parameter and the initial value of the second curve parameter.

[0146] Optionally, after determining the second curve parameter, the adjustment amount and initial value of the second curve parameter can be determined when the second curve parameter changes and other curve parameters except the second curve parameter remain unchanged, and the fit between the charge and discharge curve and the initial reference curve reaches a preset threshold. Then, a calculation method similar to the above is used to determine the value of the second curve parameter, and the current value of each curve parameter in this case can be determined.

[0147] In a method for determining a battery health state provided in an embodiment of the present application, a second curve parameter, adjusted for the deviation position, can be determined based on the deviation position between the charge and discharge curve and an initial reference curve, as well as a mapping relationship between each curve parameter and the deviation position. The deviation position can be used to more accurately determine the curve parameter that needs to be adjusted for curve fitting, and adjustments can be made to the corresponding curve parameters, thereby improving the efficiency of charge and discharge curve fitting.

[0148] It should be understood that, although the steps in the above-mentioned flowcharts are shown in sequence according to the instructions of the arrows, these steps are not necessarily performed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be performed in other orders. Moreover, at least a portion of the steps in the above-mentioned flowcharts may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily to be performed in sequence, but can be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0149] Based on the foregoing embodiments, an embodiment of the present application provides a device for determining the health status of a battery, which includes the modules included and the units included in each module, and can be implemented by a processor; of course, it can also be implemented by a specific logic circuit; in the implementation process, the processor can be a central processing unit (CPU), a microprocessor (MPU), a digital signal processor (DSP) or a field programmable gate array (FPGA), etc.

[0150] Figure 10 This is a schematic diagram of the structure of the device for determining the battery health status provided in the embodiment of the present application. Please refer to Figure 10 , the device includes: a curve adjustment module 1010, a value determination module 1020, a result calculation module 1030 and a state determination module 1040;

[0151] The curve adjustment module 1010 is used to determine the charge and discharge curve of the target battery and adjust the curve parameters of the charge and discharge curve to obtain an adjusted charge and discharge curve. The curve parameters are used to change the shape of the charge and discharge curve. The curve parameters include parameters of irreversible loss of capacity change of the target battery.

[0152] A value determination module 1020 is configured to determine current values ​​of the curve parameters based on the adjustment amount of the curve parameters and the initial values ​​of the curve parameters when the degree of fit between the charge-discharge curve and the initial reference curve reaches a preset threshold. The initial reference curve is a charge-discharge curve obtained by performing a charge-discharge test with no loss on the target battery. The initial values ​​of the curve parameters are the values ​​of the curve parameters in the initial reference curve.

[0153] A result calculation module 1030 is used to determine a battery status characterization index of the target battery according to the current value of the curve parameter;

[0154] The state determination module 1040 is configured to determine the health state of the target battery according to the battery state characterization indicator of the target battery.

[0155] In one embodiment, the result calculation module 1030 is specifically used to determine the balance value of the target battery cell after active lithium loss occurs in the film formation according to the charge and discharge curve offset after the active lithium loss occurs in the battery film formation and the initial balance value of the target battery cell; and determine the balance value of the target battery based on the balance value of the target battery cell after active lithium loss occurs in the film formation and the parameters of the irreversible loss of capacity change in the target battery.

[0156] In one embodiment, the curve adjustment module 1010 is specifically used to adjust each first curve parameter of the charge and discharge curve to obtain an adjusted charge and discharge curve, where the first curve parameter is any parameter among multiple curve parameters; the value determination module 1020 is specifically used to determine the first value of the first curve parameter according to the adjustment amount of the first curve parameter and the initial value of the first curve parameter when the first curve parameter changes and other curve parameters except the first curve parameter remain unchanged, and the fit between the charge and discharge curve and the initial reference curve reaches a preset threshold; and determine the current value of each curve parameter based on the first value of each first curve parameter.

[0157] In one embodiment, the value determination module 1020 is specifically configured to use the first value of each first curve parameter as the current value of the curve parameter.

[0158] In one embodiment, the value determination module 1020 is specifically used to determine the charge and discharge curve corresponding to each first value based on the first value of each first curve parameter; adjust each first curve parameter within a preset range threshold to determine the second value of the first curve parameter when the fit between the charge and discharge curve and the initial reference curve reaches a second preset threshold; and use the second value of each first curve parameter as the current value of the curve parameter.

[0159] In one embodiment, the value determination module 1020 is specifically used to determine the second curve parameter in the curve parameter to be adjusted for the deviation position based on the deviation position between the charge and discharge curve and the initial reference curve and the mapping relationship between each curve parameter and the deviation position; when the second curve parameter changes and other curve parameters except the second curve parameter remain unchanged, and the fit between the charge and discharge curve and the initial reference curve reaches a preset threshold, the current value of each curve parameter is determined based on the adjustment amount of the second curve parameter and the initial value of the second curve parameter.

[0160] The description of the above device embodiment is similar to the description of the above method embodiment and has similar beneficial effects as the method embodiment. For technical details not disclosed in the device embodiment of this application, please refer to the description of the method embodiment of this application for understanding.

[0161] It should be noted that in the embodiments of this application Figure 10The division of modules in the battery health status determination device shown is schematic and is only a logical functional division. In actual implementation, there may be other division methods. In addition, the functional units in the various embodiments of the present application can be integrated into a processing unit, or can exist physically separately, or two or more units can be integrated into a single unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units. It can also be implemented in the form of a combination of software and hardware.

[0162] It should be noted that, in the embodiment of the present application, if the above method is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes to the relevant technology can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for enabling an electronic device to execute all or part of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a U disk, a mobile hard disk, a read-only memory (ROM), a magnetic disk or an optical disk. In this way, the embodiment of the present application is not limited to any specific combination of hardware and software.

[0163] Figure 11 For a schematic diagram of the structure of the computer device provided in the embodiment of this application, please refer to Figure 11 The embodiment of the present application provides a computer device, which can be a professional device for determining the curve parameters of the target battery, or any type of device with computing capabilities, without specific limitation herein. Its internal structure diagram can be as follows Figure 11 As shown. The computer device includes a processor 1120, a memory, and a network interface 1140 connected via a system bus 1110. The processor 1120 of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium 1131 and an internal memory 1132. The non-volatile storage medium 1131 stores an operating system, a computer program, and a database. The internal memory 1132 provides an environment for the operation of the operating system and computer program in the non-volatile storage medium 1131. The database of the computer device is used to store data. The network interface 1140 of the computer device is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor 1120, the above method is implemented.

[0164] An embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the method provided in the above embodiment are implemented.

[0165] An embodiment of the present application provides a computer program product containing instructions, which, when executed on a computer, enables the computer to execute the steps of the method provided in the above method embodiment.

[0166] Those skilled in the art will understand that Figure 11 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0167] In one embodiment, the battery health status determination device provided by the present application can be implemented in the form of a computer program, which can be used in Figure 11 The computer device is operated on the computer device shown. The memory of the computer device can store various program modules that constitute the above-mentioned device. The computer program composed of various program modules enables the processor to execute the steps of the method of each embodiment of the present application described in this specification.

[0168] It should be noted that the description of the above storage medium and device embodiments is similar to the description of the above method embodiments and has similar beneficial effects as the method embodiments. For technical details not disclosed in the storage medium, storage medium, and device embodiments of this application, please refer to the description of the method embodiments of this application for understanding.

[0169] It should be understood that "one embodiment" or "an embodiment" or "some embodiments" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in one embodiment" or "in an embodiment" or "in some embodiments" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application. The above-mentioned serial numbers of the embodiments of the present application are for description only and do not represent the advantages and disadvantages of the embodiments. The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced to each other. For the sake of brevity, they will not be repeated here.

[0170] The term "and / or" in this article is only a description of the association relationship between associated objects, indicating that there can be three relationships. For example, object A and / or object B can mean: object A exists alone, object A and object B exist at the same time, and object B exists alone.

[0171] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0172] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The embodiments described above are merely illustrative. For example, the division of the modules is merely a logical function division. In actual implementation, there may be other division methods, such as: multiple modules or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of devices or modules can be electrical, mechanical or other forms.

[0173] The modules described above as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules; they may be located in one place or distributed across multiple network units; some or all of the modules may be selected according to actual needs to achieve the purpose of this embodiment.

[0174] In addition, all functional modules in the embodiments of the present application can be integrated into one processing unit, or each module can be a separate unit, or two or more modules can be integrated into one unit; the above-mentioned integrated modules can be implemented in the form of hardware or in the form of hardware plus software functional units.

[0175] Those skilled in the art will understand that all or part of the steps of implementing the above-mentioned method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM), magnetic disks or optical disks, and other media that can store program codes.

[0176] Alternatively, if the above-mentioned integrated unit of the present application is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application, or the part that contributes to the relevant technology, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for enabling an electronic device to execute all or part of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, ROMs, magnetic disks or optical disks.

[0177] The methods disclosed in the several method embodiments provided in this application can be arbitrarily combined without conflict to obtain new method embodiments.

[0178] The features disclosed in the several product embodiments provided in this application can be arbitrarily combined without conflict to obtain new product embodiments.

[0179] The features disclosed in the several method or device embodiments provided in this application can be arbitrarily combined without conflict to obtain new method embodiments or device embodiments.

[0180] The above is merely an embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A method for determining a battery health state, characterized in that: The method comprises: Determining a charge and discharge curve of a target battery and adjusting curve parameters of the charge and discharge curve to obtain an adjusted charge and discharge curve, wherein the curve parameters are used to change the shape of the charge and discharge curve, and the curve parameters include parameters of irreversible loss of capacity change of the target battery; When the degree of fit between the charge-discharge curve and the initial reference curve reaches a preset threshold, determining the current value of the curve parameter according to the adjustment amount of the curve parameter and the initial value of the curve parameter, wherein the initial reference curve is a charge-discharge curve obtained by performing a charge-discharge test when the target battery has no loss, and the initial value of the curve parameter is the value of the curve parameter in the initial reference curve; Determining a battery state characterization indicator of the target battery according to a current value of the curve parameter; The health state of the target battery is determined according to a battery state characterization indicator of the target battery.

2. The method according to claim 1, characterized in that The curve parameters also include: the charge-discharge curve offset after active lithium loss occurs in the battery film formation, and the battery state characterization index of the target battery is the balance value of the target battery; Determining a battery status characterization indicator of the target battery according to the current value of the curve parameter includes: Determining the balance value of the target battery cell after active lithium loss occurs in the film formation according to the charge-discharge curve offset after the active lithium loss occurs in the film formation of the target battery and the initial balance value of the target battery cell; The balance value of the target battery is determined based on the balance value of the battery cell after active lithium loss occurs in the target battery film formation and the parameter of irreversible loss of capacity change of the target battery.

3. The method according to claim 1, characterized in that The curve parameters of the charge-discharge curve are adjusted to obtain an adjusted charge-discharge curve, including: Adjusting each first curve parameter of the charge-discharge curve to obtain an adjusted charge-discharge curve, where the first curve parameter is any one of the plurality of curve parameters; When the degree of fit between the charge-discharge curve and the initial reference curve reaches a preset threshold, determining the current value of the curve parameter according to the adjustment amount of the curve parameter and the initial value of the curve parameter includes: When the first curve parameter changes and other curve parameters except the first curve parameter remain unchanged, and the degree of fit between the charge-discharge curve and the initial reference curve reaches a preset threshold, determining a first value of the first curve parameter according to an adjustment amount of the first curve parameter and an initial value of the first curve parameter; Based on the first values ​​of the first curve parameters, current values ​​of the curve parameters are determined.

4. The method according to claim 3, characterized in that The determining, based on the first values ​​of the first curve parameters, the current values ​​of the curve parameters comprises: The first value of each of the first curve parameters is used as the current value of the curve parameter.

5. The method according to claim 3, characterized in that The determining, based on the first values ​​of the first curve parameters, the current values ​​of the curve parameters comprises: Determining, based on the first values ​​of the first curve parameters, corresponding charge and discharge curves at the first values; Adjusting each of the first curve parameters within a preset range threshold, and determining a second value of the first curve parameter when the degree of fit between the charge-discharge curve and the initial reference curve reaches a second preset threshold; The second value of each of the first curve parameters is used as the current value of the curve parameter.

6. The method according to claim 1, characterized in that When the degree of fit between the charge-discharge curve and the initial reference curve reaches the highest, determining the parameter value of the adjustment parameter corresponding to the charge-discharge curve includes: Determining, according to a deviation position between the charge-discharge curve and an initial reference curve and a mapping relationship between each of the curve parameters and the deviation position, a second curve parameter among the curve parameters to be adjusted for the deviation position; When the second curve parameter changes and other curve parameters except the second curve parameter remain unchanged, and the fit between the charge and discharge curve and the initial reference curve reaches a preset threshold, the current value of each of the curve parameters is determined according to the adjustment amount of the second curve parameter and the initial value of the second curve parameter.

7. The method according to any one of claims 1 to 6, characterized in that The parameters of the irreversible loss of the target battery capacity change include: active lithium loss parameter, positive electrode active material lithium insertion loss parameter, positive electrode active material lithium removal loss parameter, negative electrode active material lithium insertion loss parameter and negative electrode active material lithium removal loss parameter.

8. A device for determining a battery health status, characterized in that: The device includes: a curve adjustment module, a value determination module, a result calculation module and a state determination module; The curve adjustment module is used to determine the charge and discharge curve of the target battery and adjust the curve parameters of the charge and discharge curve to obtain an adjusted charge and discharge curve, wherein the curve parameters are used to change the shape of the charge and discharge curve, and the curve parameters include: parameters of irreversible loss of capacity change of the target battery; The value determination module is configured to determine the current value of the curve parameter based on the adjustment amount of the curve parameter and the initial value of the curve parameter when the degree of fit between the charge and discharge curve and the initial reference curve reaches a preset threshold, wherein the initial reference curve is a charge and discharge curve obtained by performing a charge and discharge test when the target battery has no loss, and the initial value of the curve parameter is the value of the curve parameter in the initial reference curve; The result calculation module is used to determine the battery state characterization index of the target battery according to the current value of the curve parameter; The state determination module is configured to determine the health state of the target battery according to a battery state characterization indicator of the target battery.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, characterized in that: When the processor executes the program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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