Battery diagnosis device and battery diagnosis method

Abstract

According to embodiments disclosed in the present document, a battery diagnostic device is provided, the battery diagnostic device including: an interface configured to acquire a temperature curve representing a temperature change of a battery cell with respect to a voltage change of the battery cell and a capacity curve representing a capacity change of the battery cell with respect to the voltage change of the battery cell; and at least one processor, wherein the at least one processor is configured to identify a first peak representing a phase change of the battery cell based on the temperature curve, and estimate a degree of deterioration indicating a degree to which the battery cell has deteriorated based on identifying a first point corresponding to the first peak in the capacity curve.

Description

Technical Field

[0001] Cross-reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2024-0122464, filed on September 9, 2024, and Korean Patent Application No. 10-2025-0024292, filed on February 25, 2025, the disclosures of which are incorporated herein by reference. Technical Field

[0004] The embodiments disclosed in this document relate to a battery diagnostic device and a battery diagnostic method. Background Technology

[0005] Battery data used in cell diagnostics may include peaks that exhibit different characteristics depending on the charging rate. For example, battery data acquired based on a relatively fast charging rate may not include peaks representing phase transitions occurring at the negative electrode. Therefore, methods may be needed to identify phase equilibrium or phase transition states occurring within the battery, independent of the charging rate used to acquire the battery data. Summary of the Invention

[0006] Technical issues

[0007] The embodiments disclosed in this document provide a battery diagnostic device and a battery diagnostic method for using temperature profiles to diagnose the degree of battery degradation.

[0008] The embodiments disclosed in this document provide a battery diagnostic device and a battery diagnostic method for diagnosing the degree of battery degradation by inferring points on a capacity curve using a temperature curve.

[0009] The technical problems solved by the embodiments disclosed in this document are not limited to the above-described technical problems, and other technical problems not mentioned can be clearly understood by those skilled in the art from the following description.

[0010] Technical solution

[0011] According to embodiments disclosed in this document, a battery diagnostic device is provided, comprising: an interface configured to acquire a temperature profile representing a temperature change of a battery cell relative to a voltage change of the battery cell and a capacity profile representing a capacity change of the battery cell relative to a voltage change of the battery cell; and at least one processor, wherein the at least one processor is configured to identify a first peak representing a phase transition of the battery cell based on the temperature profile, and to estimate a degree of degradation indicating the extent to which the battery cell has deteriorated based on identifying a first point in the capacity profile corresponding to the first peak.

[0012] For example, at least one processor can be configured to acquire temperature and capacity profiles during the charging or discharging process of a battery cell.

[0013] For example, the first point can represent the high-potential phase transition state that occurs at the negative electrode of a single battery cell.

[0014] For example, at least one processor can be configured to identify a second point that differs from the first point based on a capacity curve, and to estimate the degree of degradation based on the difference between the first and second points.

[0015] For example, at least one processor can be configured to estimate the degree of degradation by comparing the difference between the first point and the second point with a specified difference.

[0016] For example, the second point can represent a phase transition state that is different from the high-potential phase transition state corresponding to the first point.

[0017] For example, at least one processor can be configured to acquire temperature profiles via an interface including a temperature sensor attached to a battery cell.

[0018] For example, at least one processor can be configured to control the amount of charge on a single battery cell when the degree of battery degradation exceeds a specified degree of degradation.

[0019] According to another embodiment disclosed in this document, a battery diagnostic method is provided, comprising: identifying a first peak representing a phase transition of a battery cell based on a temperature curve representing a temperature change of a battery cell relative to a voltage change of the battery cell; and estimating a degree of degradation indicating the extent to which a battery cell has deteriorated based on identifying a first point corresponding to the first peak in a capacity curve representing a capacity change of a battery cell relative to a voltage change of the battery cell.

[0020] For example, battery diagnostic methods may include acquiring temperature and capacity profiles during the charging or discharging process of a single battery cell.

[0021] For example, operations for estimating the degree of degradation may include operations for identifying a second point that differs from the first point based on the capacity curve, and operations for estimating the degree of degradation based on the difference between the first point and the second point.

[0022] For example, the operation of estimating the degree of degradation may also include estimating the degree of degradation by comparing the difference between the first point and the second point with a specified difference.

[0023] For example, the second point can represent a phase transition state that is different from the high-potential phase transition state corresponding to the first point.

[0024] For example, battery diagnostic methods may include operations that acquire temperature profiles via an interface including a temperature sensor attached to a single battery cell.

[0025] For example, a battery diagnostic method may include controlling the amount of charge on individual battery cells when the degree of battery degradation exceeds a specified degree of degradation.

[0026] Beneficial effects

[0027] The battery diagnostic apparatus and battery diagnostic method according to the embodiments disclosed in this document can use temperature profiles to diagnose the degree of battery degradation.

[0028] The battery diagnostic apparatus and battery diagnostic method according to embodiments disclosed in this document can diagnose the degree of battery degradation by inferring points on the capacity curve using temperature curves.

[0029] In addition, various effects that can be directly or indirectly identified through this document can be provided. Attached Figure Description

[0030] Figure 1 This is a block diagram illustrating a battery pack according to an embodiment disclosed in this document.

[0031] Figure 2 This is a block diagram illustrating the configuration of a battery diagnostic device according to an embodiment disclosed in this document.

[0032] Figure 3 An example of a graph representing data related to a single battery cell according to an embodiment disclosed in this document is illustrated.

[0033] Figure 4 An example of a graph representing data related to a single battery cell according to an embodiment disclosed in this document is illustrated.

[0034] Figure 5 An example of a graph representing data related to a single battery cell according to an embodiment disclosed in this document is illustrated.

[0035] Figure 6 An example flowchart illustrating operations performed by a battery diagnostic device according to embodiments disclosed in this document is shown.

[0036] Figure 7 The illustration shows a computational system that performs a battery diagnostic method according to an embodiment disclosed in this document. Detailed Implementation

[0037] In the following description, some embodiments described in this document are illustrated with reference to the accompanying drawings. However, this is not intended to limit the technology to the specific embodiments, but should be understood to include various modifications, equivalents, and / or substitutions of the embodiments of the technology.

[0038] When adding reference numerals to components in each of the accompanying drawings, it should be noted that the same components are given the same reference numerals whenever possible, even if the same components are shown in different drawings. Furthermore, in describing the various embodiments disclosed in this document, detailed descriptions of relevant known configurations or functions are omitted if it is determined that such detailed descriptions would impede understanding of the embodiments of this disclosure. Nouns corresponding to the singular form of an item may include one or more items unless the relevant context clearly indicates otherwise.

[0039] In describing the components of the embodiments described in this document, terms such as first, second, A, B, (a), (b), etc., may be used. These terms are intended only to distinguish these components from other components, and the nature, order, or sequence of the components is not limited by these terms. Furthermore, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments disclosed in this document pertain. Terms defined in common dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and should not be interpreted in an ideal or overly formal sense unless expressly defined in this application.

[0040] Furthermore, in this disclosure, the expressions "greater than" or "less than" may be used to determine whether a specific condition is met or achieved, but this is only for illustrative purposes and does not exclude descriptions of "greater than or equal to" or "less than or equal to". A condition described as "greater than or equal to" may be replaced with "greater than", a condition described as "less than or equal to" may be replaced with "less than", and a condition described as "greater than or equal to and less than" may be replaced with "greater than and less than or equal to". Additionally, in the following text, "A" to "B" means at least one of the elements from A (inclusive) to B (inclusive).

[0041] In this document, each of the phrases “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C” and “at least one of A, B or C” may include any one of the items listed together in the corresponding phrase or all possible combinations thereof.

[0042] In this document, when a component (e.g., a first component) is referred to as “connected,” “coupled,” or “joined” to another component (e.g., a second component), whether or not the terms “functionally” or “communically” are used, it means that the component can be connected to the other component directly (e.g., via a wired connection), wirelessly, or via a third component.

[0043] Methods according to the various embodiments disclosed in this document can be provided by being included in a computer program product. The computer program product can be traded as a product between a seller and a buyer. The computer program product can be distributed in the form of a machine-readable recording medium (e.g., an optical disc read-only memory (CD-ROM)), or distributed through an app store, directly between two user devices, or distributed online (e.g., downloaded or uploaded). In the case of online distribution, at least a portion of the computer program product can be temporarily stored or temporarily generated in a machine-readable recording medium, such as the memory of a manufacturer's server, an app store's server, or a relay server.

[0044] According to various embodiments, each of the above-described components (e.g., modules or programs) may include one or more entities, and some of the multiple entities may be separated and placed in other components. According to various embodiments, one or more of the above-described components or operations may be omitted, or one or more other components or operations may be added. Alternatively or additionally, multiple components (e.g., modules or programs) may be integrated into a single component. In this case, the integrated component may perform one or more functions of each of the multiple components in the same or similar manner as the functions performed by the corresponding components among the multiple components prior to integration. According to various embodiments, operations performed by modules, programs, or other components may be performed sequentially, in parallel, repeatedly, or heuristically, or one or more operations may be performed in a different order, omitted, or performed by adding one or more other operations.

[0045] Figure 1 This is a block diagram illustrating a battery pack according to an embodiment disclosed in this document.

[0046] refer to Figure 1 This schematically illustrates a battery control system comprising a battery pack 1 and a higher-level controller 2 included in a higher-level system, according to an embodiment disclosed in this document.

[0047] like Figure 1 As shown, the battery pack 1 may include a plurality of battery cells 11, a switching unit 14 connected in series with the first terminal side and / or the second terminal side of the plurality of battery cells 11 to control the flow of charging and / or discharging current of the plurality of battery cells 11, and a battery management system 20 that monitors the voltage, current, temperature, etc. of the battery pack 1 to prevent overcharging and over-discharging.

[0048] In this configuration, the battery pack 1 may be equipped with multiple battery cells 11, a sensor 12, a switching unit 14, and a battery management system 20. For example, the first terminal may be the positive (+) terminal of the multiple battery cells 11, and the second terminal may be their negative (-) terminal.

[0049] Here, the switching unit 14 is a device for controlling the current flow to charge or discharge multiple battery cells 11, and may, for example, use at least one relay, magnetic contactor, etc., depending on the specifications of the battery pack 1.

[0050] For example, the plurality of battery cells 11 may include cylindrical batteries. A cylindrical battery can refer to a battery in which battery materials are packaged into a cylindrical shape. Since the plurality of battery cells 11 include cylindrical batteries, if lithium deposition occurs inside the cylindrical batteries during constant voltage charging of the plurality of battery cells 11, an increase in the current flowing through the plurality of battery cells 11 may occur.

[0051] The battery management system 20 is an interface for receiving values ​​obtained by measuring the various parameters described above, and may include multiple terminals, circuitry connected to these terminals, and processing of the received values. Furthermore, the battery management system 20 can control the switching unit 14—such as a relay or contactor—on / off, and can be connected to individual battery cells 11 to monitor the state of each of the multiple battery cells 11.

[0052] The upper-level controller 2 can send control signals for multiple battery cells 11 to the battery management system 20. Therefore, the operation of the battery management system 20 can be controlled based on the signals applied from the upper-level controller 2.

[0053] According to this embodiment, the battery management system 20 may include Figure 2 The battery diagnostic device 100. According to another embodiment, the battery management system 20 may be different from... Figure 2 Another system of the battery diagnostic equipment 100. That is to say, Figure 2 The battery diagnostic device 100 can be included in the battery pack 1 or configured as another device outside the battery pack 1. For ease of description, it will be described assuming that the battery diagnostic device 100 is configured as another device outside the battery pack 1.

[0054] Figure 2 This is a block diagram illustrating the configuration of a battery diagnostic device according to an embodiment disclosed in this document.

[0055] The battery diagnostic device 100 according to an embodiment may include at least one of a processor 110, a memory 120, and an interface 130. The processor 110, memory 120, and interface 130 may be electronically and / or operatively coupled to each other via electronic components including a communication bus. Hereinafter, operatively coupling multiple hardware components to each other may mean a direct and / or indirect connection between multiple hardware components established in a wired and / or wireless manner, such that a second hardware component is controlled by a first hardware component among the multiple hardware components. Although multiple hardware components are shown in different blocks, the embodiment is not limited thereto. Figure 1 Some hardware (e.g., at least a portion of processor 110, memory 120, and communication circuitry (not shown)) may be included in a single integrated circuit such as a system-on-a-chip (SoC). Communication methods between components may include buses, general purpose input and output (GPIO), serial peripheral interface (SPI), mobile industrial processor interface (MIPI), etc.

[0056] The processor 110 of the battery diagnostic device 100 according to an embodiment may include hardware components for processing data based on one or more instructions. The hardware components for processing data may include, for example, an arithmetic and logic unit (ALU), a floating-point unit (FPU), a field-programmable gate array (FPGA), a central processing unit (CPU), a microcontroller unit (MCU), and / or an application processor (AP). The number of processors 110 may be one or more. For example, processor 110 may have a multi-core processor architecture, having dual-core, quad-core, hexa-core, or octa-core cores.

[0057] The memory 120 of the battery diagnostic device 100 according to an embodiment may include hardware components for storing data and / or instructions input to and / or output from the processor 110. The memory 120 may include volatile memory such as random access memory (RAM) and / or non-volatile memory such as read-only memory (ROM). For example, the volatile memory may include at least one of dynamic RAM (DRAM), static RAM (SRAM), cache RAM, and pseudo SRAM (PSRAM). For example, the non-volatile memory may include at least one of programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), flash memory, hard disk, optical disk, solid-state drive (SSD), and embedded multimedia card (eMMC).

[0058] The interface 130 of the battery diagnostic device 100 according to an embodiment can be configured to generate battery measurement values ​​from the battery. For this purpose, the interface 130 may include measuring devices such as a voltmeter, ammeter, thermometer, etc., and / or a communication module for establishing a communication link with an external device. As an example, the interface 130 may include a temperature sensor attached to a single battery cell.

[0059] For example, interface 130 can be configured to acquire a temperature curve representing the relationship between the voltage of a battery cell and the temperature of the battery cell. Interface 130 can be configured to acquire a capacity curve representing the relationship between the voltage of a battery cell and the capacity of the battery cell.

[0060] For example, a temperature profile can represent the temperature of a single battery cell relative to its voltage. A temperature profile can represent the temperature change of a single battery cell relative to a change in voltage.

[0061] For example, a capacity curve can represent the capacity of a single battery cell relative to voltage. A capacity curve can represent the capacity change of a single battery cell relative to voltage variations.

[0062] In other words, the battery diagnostic device 100 can use interface 130 to acquire battery-related data (or differential data obtained by modifying (or differentiating) the data). The battery diagnostic device 100 can acquire battery-related data (e.g., capacity profiles or temperature profiles) during the charging or discharging process of a battery cell.

[0063] In an embodiment, the battery diagnostic device 100 can obtain temperature and capacity profiles based on a charging rate exceeding a specified charging rate (e.g., 0.33 C rate).

[0064] For example, charging a battery cell at a rate exceeding a specified charging rate can be termed high-rate charging. When charging a battery cell at a high rate, because the battery cell is charged through overvoltage, at least one of the peak values ​​reflecting the characteristics of the battery cell may not be identified in the capacity data.

[0065] For example, battery diagnostic device 100 can use a temperature profile to identify at least one unidentified peak. In this case, battery diagnostic device 100 maps the voltage range of the temperature profile to the voltage range of the capacity profile.

[0066] According to an embodiment, the processor 110 can identify a first peak based on a temperature profile. For example, the processor 110 can estimate the degree of degradation, indicating the extent of degradation of a battery cell, based on identifying a first point in a capacity profile corresponding to the first peak. For example, when the degree of battery degradation exceeds a specified degree of degradation (or a reference degree of degradation), the processor 110 can control the charging amount of the battery cell. For example, the processor 110 can control the charging amount of the battery cell such that the capacity of the battery cell does not exceed a specified capacity. For example, the processor 110 can control the discharging amount of the battery cell such that the capacity of the battery cell is not reduced to less than a specified capacity. However, it is not limited to these methods. For example, the processor 110 can provide a signal including the degree of degradation of the battery cell to an external device based on an estimated degree of degradation of the battery cell.

[0067] For example, the first point corresponding to the first peak value identified by the processor 110 can represent a high-potential phase equilibrium state (or high-potential phase transition state) occurring at the negative electrode of the battery cell. In other words, the first peak value corresponding to the first point can represent a high-potential phase equilibrium state occurring at the negative electrode of the battery cell. For example, the high potential can fall within a region exceeding the average value across the entire voltage range of the battery cell.

[0068] For example, the phase equilibrium state can include the phase transition state. That is, the peak value corresponding to the first point can represent the phase equilibrium state and / or phase transition state that occurs within the battery cell.

[0069] For example, phase equilibrium can occur several times during the charging or discharging process of a battery cell. When phase equilibrium occurs, a peak can appear in the capacity curve of the battery cell (e.g., the differential capacity curve). In other words, the phase equilibrium that occurs inside the battery can be represented by a peak in the differential capacity curve of the battery cell.

[0070] For example, a peak could be a point where the instantaneous rate of change of the differential capacitance with respect to voltage is zero, a point where the instantaneous rate of change of the differential capacitance with respect to voltage is positive on a lower voltage side compared to the point where the instantaneous rate of change is zero, and a point where the instantaneous rate of change of the differential capacitance with respect to voltage is negative on a higher voltage side compared to the point where the instantaneous rate of change is zero.

[0071] For example, a peak could be a point where the instantaneous rate of change of the differential capacitance with respect to voltage is zero, a point on a lower voltage side where the instantaneous rate of change of the differential capacitance with respect to voltage is negative, and a point on a higher voltage side where the instantaneous rate of change of the differential capacitance with respect to voltage is positive.

[0072] For example, phase equilibrium can refer to a state in which the structure and chemical state of the negative electrode material in a battery cell are stable and in equilibrium. For example, in a phase equilibrium state, the lithium-ion concentration can remain constant. For example, in a phase equilibrium state, the solid electrolyte interphase (SEI) layer can be stably maintained. For example, in a phase equilibrium state, the voltage of the battery cell can be stably maintained.

[0073] For example, a phase transition state can include the process of switching from one phase to another within a battery cell. In other words, the crystal structure within a battery cell can change during a phase transition state.

[0074] For example, when using temperature and capacity curves obtained based on a charging rate less than a specified charging rate, the battery diagnostic device 100 can use the capacity curve within the temperature and capacity curves to identify the first point, and thus can bypass the operation of identifying the first peak. However, when using temperature and capacity curves obtained based on a charging rate exceeding the specified charging rate, the first point within the capacity curve cannot be identified, and therefore the battery diagnostic device 100 can use the first peak of the temperature curve to indirectly identify the first point in the capacity curve.

[0075] According to an embodiment, the battery diagnostic device 100 can identify a second point that differs from the first point. For example, the second point may correspond to a voltage lower than the voltage corresponding to the first point.

[0076] For example, battery diagnostic device 100 can estimate the degree of degradation based on the difference between a first point and a second point. The difference between the first point and the second point can include the length between the first point and the second point.

[0077] For example, battery diagnostic device 100 can estimate the degree of degradation by comparing the difference between a first point and a second point with a specified difference. For example, the specified difference can be obtained based on reference data including the difference between the first point and the second point of a battery cell at the beginning of life (BOL) state.

[0078] For example, the second point can represent a phase equilibrium state different from the high-potential phase equilibrium state corresponding to the first point. For example, the other phase equilibrium state corresponding to the second point can precede the high-potential phase equilibrium state corresponding to the first point. In other words, temporally, the other phase equilibrium state corresponding to the second point can occur earlier than the high-potential phase equilibrium state corresponding to the first point. For example, the high-potential phase equilibrium state corresponding to the first point can refer to the sixth phase equilibrium state (or phase transition state), and the other phase equilibrium state corresponding to the second point can refer to the second phase equilibrium state (or phase transition state).

[0079] For example, when the battery diagnostic device 100 identifies a second point, it can designate a voltage region higher than the second point as a region of interest. The battery diagnostic device 100 can then identify the peak value corresponding to the first point by setting the region of interest. As an example, the peak value corresponding to the first point can be identified in the temperature profile corresponding to the region of interest.

[0080] The battery diagnostic device 100 according to the embodiment described above can infer a first point indicating a high potential balance state not identified in the capacity curve by using a temperature profile obtained based on a charging rate exceeding a specified charging rate. For example, the battery diagnostic device 100 can estimate the degree of degradation of a single battery cell by identifying the first point indicating a high potential balance using the temperature profile independently of the charging rate.

[0081] Figure 3 An example of a graph 300 representing data related to a single battery cell, according to an embodiment disclosed in this document, is illustrated. Figure 3 Battery diagnostic equipment 100 can be referenced. Figure 2 The battery diagnostic device 100 includes, for example, a capacity curve 300 that represents the capacity change of a battery cell relative to a voltage change in the battery cell (e.g., dQ / dV data). The capacity curve 320 can represent the capacity change of the entire battery cell relative to a voltage change in the whole battery cell. However, it is not limited to this. As an example, the capacity curve 320 can represent the capacity change of the positive electrode within the battery cell relative to a voltage change in the positive electrode within the battery cell. The capacity curve 320 can represent the capacity change of the negative electrode within the battery cell relative to a voltage change in the negative electrode within the battery cell. For example, the graph 300 can include a temperature curve 310 that represents the temperature change of the battery cell relative to a voltage change in the battery cell.

[0082] In an embodiment, the capacity curve 320 may include one or more points. For example, one or more points may be used in an algorithm used to analyze the quality (or state) of a battery cell.

[0083] For example, one or more points may include points where the slope of the graph corresponding to capacity curve 320 changes. Points where the slope changes may include points where the slope value changes from positive to negative (or from negative to positive) based on that point. As an example, at least one of the one or more points may include points where the slope of the graph is constant, depending on the charging rate (or charging speed) used to obtain capacity curve 320. Points with a constant slope may include points other than points where the slope value changes from positive to negative (or from negative to positive) based on that point. For example, the point may represent a phase transition state or phase equilibrium state occurring within a single battery cell.

[0084] For example, temperature curve 310 may include one or more peaks. These peaks may correspond to one or more points included in capacity curve 320. These peaks may be referred to as one or more extreme values.

[0085] For example, battery diagnostic device 100 can identify a first peak 330 in temperature curve 310. For example, battery diagnostic device 100 can identify a voltage value 331 corresponding to the first peak 330 based on the identification of the first peak 330. For example, battery diagnostic device 100 can identify a first point in capacity curve 320 corresponding to the voltage value 331 based on the identification of the voltage value 331. The first point can represent a high-potential phase equilibrium state of a single battery cell occurring at a sixth time. For example, the first point can be located at a point with a constant slope.

[0086] In the following text, see references Figure 4 and Figure 5 The operation of the battery diagnostic device 100 to identify the first point based on the temperature profile of the battery cell will be described in more detail.

[0087] Figure 4 An example of a graph 400 representing data related to a single battery cell, according to an embodiment disclosed in this document, is illustrated. Figure 5 An example of a graph 500 representing data related to a single battery cell, according to an embodiment disclosed in this document, is illustrated. Figure 4 and Figure 5 Battery diagnostic equipment 100 can be referenced. Figure 2 Battery diagnostic equipment 100.

[0088] refer to Figure 4 The graph 400 may include a temperature curve 410 and a capacity curve 420 obtained by the battery diagnostic device 100 according to the embodiment based on a charging rate (e.g., 0.05 C rate) less than a specified charging rate. The temperature curve 410 may represent the temperature change of a single battery cell relative to a voltage change, and the capacity curve 420 may represent the capacity change of a single battery cell relative to a voltage change.

[0089] In this embodiment, the temperature profile 410 may include one or more peaks. The battery diagnostic device 100 may identify a first peak 411 in the temperature profile 410. The battery diagnostic device 100 may identify a voltage value 430 corresponding to the first peak 411. For example, the battery diagnostic device 100 may identify a point 421 in the capacity profile 420 corresponding to the voltage value 430 based on the identified voltage value 430.

[0090] In this embodiment, since the capacity curve 420 is obtained based on a charging rate less than a specified charging rate, point 421 can be referred to as a peak in the capacity curve 420. That is, point 421 can be referred to as a peak, at which the sign of the slope changes with reference to that point. Because point 421 exhibits the characteristic of being a peak, the battery diagnostic device 100 can bypass operation using the temperature curve 410 and use the capacity curve 420 to identify point 421. However, it is not limited to this. The battery diagnostic device 100 can use the temperature curve 410 to identify point 421 within the capacity curve 420 independently of the charging rate used to acquire battery data.

[0091] refer to Figure 5 The graph 500 may include a temperature curve 510 and a capacity curve 520 obtained by the battery diagnostic device 100 according to the embodiment based on a charging rate exceeding a specified charging rate (e.g., 0.33 C rate). The temperature curve 510 may represent the temperature change of a single battery cell relative to a voltage change, and the capacity curve 520 may represent the capacity change of a single battery cell relative to a voltage change.

[0092] In an embodiment, temperature profile 510 may include one or more peaks. Battery diagnostic device 100 may identify a first peak 511 in temperature profile 510. Battery diagnostic device 100 may identify a voltage value 530 corresponding to the first peak 511. For example, battery diagnostic device 100 may identify a first point 521 in capacity profile 520 corresponding to voltage value 530 based on the identified voltage value 530.

[0093] In this embodiment, since the capacity curve 520 is obtained based on a charging rate exceeding a specified charging rate, the battery diagnostic device 100 may not be able to use the capacity curve 520 to identify the first point 521. That is, the sign of the slope may not change with reference to the first point 521. Since the first point 521 does not exhibit the characteristic of being a peak, the battery diagnostic device 100 can use the temperature curve 510 to identify the first point 521 in the capacity curve 520. In other words, when battery data (e.g., a capacity curve or a temperature curve) is obtained based on a charging rate exceeding a specified charging rate, the first peak 511 included in the temperature curve 510 can be used to identify the first point 521 included in the capacity curve 520.

[0094] According to the embodiment, the battery diagnostic device 100 can identify a second point 522. The second point 522 can represent a phase equilibrium state that occurs earlier than the phase equilibrium state corresponding to the first point 521 while the battery cell is being charged. For example, the second point 522 can represent a second phase equilibrium state among phase equilibrium states that occur while the battery cell is being charged or discharged.

[0095] For example, battery diagnostic device 100 can identify the difference (or length) between a first point 521 and a second point 522. Battery diagnostic device 100 can identify the degree of degradation of a single battery cell by comparing the difference between the first point 521 and the second point 522 with a specified difference. As an example, the difference between the first point 521 and the second point 522 can decrease as the battery cell deteriorates.

[0096] For example, the difference between the first point 521 and the second point 522 may include the difference between the voltage value corresponding to the first point 521 and the voltage value corresponding to the second point 522.

[0097] The battery diagnostic device 100 according to the embodiment described above can use a temperature profile to identify the point where a phase equilibrium state has occurred, used to identify the degree of degradation of a battery cell. When the battery diagnostic device 100 cannot use a capacity profile to identify the point where a phase equilibrium state has occurred, the battery diagnostic device 100 can use a temperature profile to identify the point where a phase equilibrium state has occurred. The battery diagnostic device 100 can identify the degree of degradation of a battery cell using the capacity and temperature profiles independently of the charging rate used to obtain the capacity and temperature profiles. That is, the battery diagnostic device 100 can identify the point for measuring the degree of degradation of a battery cell in the capacity profile obtained based on a charging rate exceeding a specified charging rate by using a temperature profile.

[0098] Figure 6 An example flowchart illustrating operations performed by a battery diagnostic device according to embodiments disclosed in this document is shown.

[0099] Figure 6 This is a flowchart illustrating a battery diagnostic method according to an embodiment disclosed in this document. In the following, it is assumed that... Figure 2 Battery diagnostic equipment 100 performs Figure 6 The process. Furthermore, the operations described as being performed by the device can be understood as being controlled by the processor 110 of the battery diagnostic device 100. Figure 7 Each operation in the process can be executed sequentially, but not necessarily sequentially. For example, the order of each operation in the process can be changed, and at least two operations can be executed in parallel. In addition, the operation of the battery diagnostic device 100 can be performed by the battery management system (BMS) in the vehicle, and can also be performed in various devices such as servers, cloud, chargers, or charger / dischargers.

[0100] refer to Figure 6In operation S610, the battery diagnostic device according to the embodiment can be based on a temperature profile (e.g., Figure 5 The temperature curve 510) is used to identify the first peak (e.g., Figure 5 The first peak was 511).

[0101] For example, a battery diagnostic device can acquire temperature and capacity profiles based on a charging rate (or charging speed) exceeding a specified charging rate (or charging speed). For example, the temperature profile may include one or more peaks. For example, the battery diagnostic device may set a range for identifying a first peak among the one or more peaks. The battery diagnostic device can identify the voltage value corresponding to the first peak (e.g., ...) by identifying the first peak within the set range. Figure 5 (Voltage value 530).

[0102] refer to Figure 6 In operation S620, the battery diagnostic device according to the embodiment can estimate the degree of degradation indicating the extent to which a battery cell has deteriorated based on identifying a first point corresponding to a first peak in the capacity curve.

[0103] For example, a battery diagnostic device can identify a first point corresponding to a voltage value corresponding to a first peak (e.g., Figure 5 The first point (521). The first point can represent the phase equilibrium state that occurs in a single battery cell.

[0104] For example, battery diagnostic equipment can identify a second point that differs from the first point (e.g., Figure 5 (Point 2, 522). Battery diagnostic equipment can determine the shrinkage rate by using the difference (or length) between the first and second points. For example, the battery diagnostic equipment can determine the shrinkage rate of a battery cell by comparing the difference between the first and second points with a specified difference (e.g., a specified difference identified by reference data obtained from a battery cell in the BOL state). The battery diagnostic equipment can estimate the degree of degradation of the battery cell based on the determined shrinkage rate.

[0105] For example, a specified difference can be set based on user input. For instance, the specified difference could include the average of the differences between each of multiple battery cells.

[0106] For example, when the degree of degradation exceeds a specified level, battery diagnostic equipment can control the charging of individual battery cells. The specified degree of degradation can be identified through data to extend the lifespan of individual battery cells. For instance, controlling the charging of individual battery cells may include setting an upper limit on the amount of charge a battery cell can receive, setting a lower limit on the amount of discharge a battery cell can receive, and / or limiting the charging rate used to charge the battery cells.

[0107] Figure 7 The illustration shows a computational system that performs a battery diagnostic method according to an embodiment disclosed in this document.

[0108] refer to Figure 7 The computing system 1000 according to the embodiments disclosed in this document may include an MCU 1010, a memory 1020, an input / output I / F 1030, and a communication I / F 1040.

[0109] The MCU 1010 can be a processor that executes various programs stored in the memory 1020 (e.g., SOH calculation program, single-cell balance target determination program, etc.). These programs process various data, including the state of charge (SOC) and state of health (SOH) of multiple battery cells, and execute reference... Figures 2 to 6 The battery diagnostic device 100 is described in terms of its functions. The MCU 1010 can be, but is not limited to, a BMS, a separate PC, or the cloud.

[0110] The memory 1020 can store various procedures related to calculating the state of harmonics (SOH) of individual battery cells and determining targets for cell balancing. Furthermore, the memory 1020 can store various data, such as the state of charge (SOC) and state of harmonics (SOH) data for each individual battery cell.

[0111] Multiple such memories 1020 can be provided as needed. Memory 1020 can be volatile or non-volatile memory. Memory 1020 used as volatile memory can be RAM, DRAM, SRAM, etc. Memory 1020 used as non-volatile memory can be ROM, PROM, EAROM, EPROM, EEPROM, flash memory, etc. The examples of memory 1020 listed above are merely examples and are not limited to these examples.

[0112] The Input / Output I / F 1030 provides an interface that allows data to be sent and received by connecting input devices (not shown) such as a keyboard, mouse, or touch panel and output devices (not shown) such as a display to the MCU 1010.

[0113] The Communication I / F 1040 is configured to send and receive various data with a server and can be a variety of devices that support wired or wireless communication. For example, programs or various data used to calculate the State of Harm (SOH) of a battery cell or determine a balance target can be sent to and received from a separately provided external server via the Communication I / F 1040.

[0114] Thus, the battery diagnostic method according to the embodiments disclosed in this document can be recorded in memory 1020 and executed by MCU 1010.

[0115] In the foregoing, although all components constituting the embodiments disclosed in this document have been described as being combined or operated in combination, the embodiments disclosed in this document are not necessarily limited to such embodiments. That is, within the scope of the purposes of the embodiments disclosed in this document, all components may be selectively combined and operated in one or more combinations.

[0116] Furthermore, unless otherwise expressly stated, the terms "comprising," "configured," or "having" above mean that the corresponding component may be included, and therefore should be interpreted as capable of further including, rather than excluding, other components. Unless otherwise defined, all terms including technical or scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments disclosed in this document pertain. Commonly used terms, such as those defined in dictionaries, should be interpreted as consistent with the meaning in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense unless explicitly defined in this document.

[0117] The above description is merely an example of the technical concepts disclosed in this document, and those skilled in the art to which the embodiments disclosed in this document pertain can make various modifications and variations without departing from the basic characteristics of the embodiments disclosed in this document. Therefore, the embodiments disclosed in this document are intended to describe, not limit, the technical concepts of the embodiments disclosed in this document, and the scope of the technical concepts disclosed in this document is not limited by these embodiments. The scope of protection of the technical concepts disclosed in this document should be interpreted by the scope of the appended claims, and all technical concepts within the equivalent scope should be interpreted as being included within the scope of the rights in this document.

Claims

1. A battery diagnostic device, comprising: An interface configured to acquire a temperature curve representing the temperature change of a battery cell relative to a voltage change and a capacity curve representing the capacity change of a battery cell relative to a voltage change. as well as At least one processor, The at least one processor is configured to identify a first peak representing the phase transition of the battery cell based on the temperature curve; and The degree of degradation, indicating the extent to which the battery cell has deteriorated, is estimated by identifying a first point in the capacity curve corresponding to the first peak.

2. The battery diagnostic device according to claim 1, wherein, The at least one processor is configured to acquire the temperature profile and the capacity profile during the charging or discharging process of the battery cell.

3. The battery diagnostic device according to claim 1, wherein, The first point represents the high-potential phase transition state that occurs at the negative electrode of the battery cell.

4. The battery diagnostic device according to claim 1, wherein, The at least one processor is configured to: Based on the capacity curve, a second point different from the first point is identified, and The degree of degradation is estimated based on the difference between the first point and the second point.

5. The battery diagnostic device according to claim 4, wherein, The at least one processor is configured to estimate the degree of degradation by comparing the difference between the first point and the second point with a specified difference.

6. The battery diagnostic device according to claim 4, wherein, The second point represents a phase transition state that is different from the high-potential phase transition state corresponding to the first point.

7. The battery diagnostic device according to claim 1, wherein, The at least one processor is configured to acquire the temperature profile via the interface including a temperature sensor attached to the battery cell.

8. The battery diagnostic device according to claim 1, wherein, The at least one processor is configured to control the amount of charge on the battery cell when the degree of degradation of the battery exceeds a specified degree of degradation.

9. A battery diagnostic method, comprising: The operation of identifying the first peak of the phase transition of the battery cell based on the temperature curve representing the temperature change of the battery cell relative to the voltage change of the battery cell; as well as The operation of estimating the degree of degradation, which indicates the extent to which the battery cell has deteriorated, is based on identifying a first point corresponding to the first peak in a capacity curve representing the capacity change of the battery cell relative to the voltage change of the battery cell.

10. The battery diagnostic method according to claim 9, further comprising: The operation of acquiring the temperature profile and the capacity profile during the charging or discharging process of the battery cell.

11. The battery diagnostic method according to claim 9, wherein, The operations for estimating the degree of degradation include: Based on the capacity curve, identify the operation at the second point that differs from the first point; and The operation of estimating the degree of degradation based on the difference between the first point and the second point.

12. The battery diagnostic method according to claim 11, wherein, The operation of estimating the degree of degradation also includes estimating the degree of degradation by comparing the difference between the first point and the second point with a specified difference.

13. The battery diagnostic method according to claim 11, wherein, The second point represents a phase transition state that is different from the high-potential phase transition state corresponding to the first point.

14. The battery diagnostic method according to claim 9, further comprising: The operation of acquiring the temperature profile via the interface including a temperature sensor attached to the individual battery cell.

15. The battery diagnostic method according to claim 9, wherein, The battery diagnostic method includes controlling the charging amount of the individual battery cells when the degree of degradation of the battery exceeds a specified degree of degradation.

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