Battery diagnosis device and battery diagnosis method

Abstract

A battery diagnosis device according to one embodiment disclosed in the present document may comprise: an interface for acquiring a capacity profile indicating a voltage with respect to the capacity of a battery cell; and at least one processor, wherein the at least one processor is configured to: acquire a positive electrode profile indicating a voltage with respect to the capacity of a positive electrode of the battery cell, and a negative electrode profile indicating a voltage with respect to the capacity of a negative electrode of the battery cell; and diagnose the state of the battery cell on the basis of a first value of the positive electrode profile and a second value of the negative electrode profile.

Description

Battery diagnostic device and battery diagnostic method

[0001] Cross-citation with related applications

[0002] The present invention claims the benefit of priority based on Korean Patent Application No. 10-2024-0191744 filed on December 19, 2024, and includes all contents disclosed in the document of said Korean patent application as part of this specification.

[0003] Technology field

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

[0005] Recently, active research and development on secondary batteries has been underway. Here, secondary batteries refer to rechargeable batteries, encompassing conventional Ni / Cd and Ni / MH batteries as well as the more recent lithium-ion batteries. Among secondary batteries, lithium-ion batteries have the advantage of significantly higher energy density compared to conventional Ni / Cd and Ni / MH batteries. Furthermore, lithium-ion batteries can be manufactured in a compact and lightweight manner, making them suitable for use as power sources for mobile devices. Recently, their scope of application has expanded to include electric vehicles, drawing attention as a next-generation energy storage medium.

[0006] During the manufacturing process of such batteries, it is necessary to diagnose the batteries and identify defective cells regarding factors that may affect battery quality. Therefore, a battery diagnostic method based on non-destructive techniques may require a method to separate the positive and negative half-cell data from full-cell data using curve fitting and to determine whether the battery cells are defective based on the half-cell data.

[0007] According to one embodiment disclosed in this document, a battery diagnostic device and a battery diagnostic method are provided that can determine whether a battery cell is defective without disassembling the battery cell.

[0008] In addition, according to one embodiment disclosed in this document, the defect status of a battery cell can be determined by using both the positive profile and the negative profile.

[0009] The technical problems of the embodiments disclosed in this document are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description below.

[0010] A battery diagnostic device according to one embodiment disclosed in this document includes an interface for obtaining a capacity profile representing a voltage for the capacity of a battery cell; and at least one processor, wherein the at least one processor may be configured to obtain a positive profile representing a voltage for the capacity of the positive electrode of the battery cell and a negative profile representing a voltage for the capacity of the negative electrode of the battery cell, and to diagnose the state of the battery cell based on a first value of the positive profile and a second value of the negative profile.

[0011] For example, the at least one processor may be configured to diagnose the state of the battery cell as abnormal if the difference between the first value and the second value falls outside a specified range.

[0012] For example, the above at least one processor may be configured to temporarily suspend the use of a preset area of ​​the state of charge (SOC) of a battery pack including the battery cell when the state of the battery cell is diagnosed as abnormal.

[0013] For example, the above abnormal condition may include an overhang defect condition in which the difference between the area of ​​the positive electrode of the battery cell and the area of ​​the negative electrode of the battery cell exceeds a specified range.

[0014] For example, the at least one processor may be configured to change the anode profile and the cathode profile such that a simulation profile representing the difference between the anode profile and the cathode profile corresponds to the capacity profile.

[0015] For example, the at least one processor may be configured to identify the first value and the second value based on changing the anode profile and the cathode profile.

[0016] For example, the first value and the second value may correspond to the initial values ​​of the capacity profile of the battery cell.

[0017] The difference between the first value and the second value may represent the available lithium loss of the battery cell.

[0018] A battery diagnostic method according to one embodiment disclosed in this document may include the operation of obtaining a positive profile representing a voltage for the capacity of the positive electrode of a battery cell and a negative profile representing a voltage for the capacity of the negative electrode of the battery cell, and the operation of diagnosing the state of the battery cell based on a first value of the positive profile and a second value of the negative profile.

[0019] For example, the operation of diagnosing the state of the battery cell may include diagnosing the state of the battery cell as abnormal when the difference between the first value and the second value exceeds a specified range.

[0020] For example, the operation of diagnosing the state of the battery cell as abnormal may include, when the state of the battery cell is diagnosed as abnormal, temporarily suspending the use of a preset area among the state of charge (SOC) areas of the battery pack including the battery cell.

[0021] For example, the above abnormal condition may include an overhang defect condition in which the difference between the area of ​​the positive electrode of the battery cell and the area of ​​the negative electrode of the battery cell exceeds a specified range.

[0022] For example, the operation of obtaining the anode profile and the cathode profile may include the operation of changing the anode profile and the cathode profile so that a simulation profile representing the difference between the anode profile and the cathode profile corresponds to the capacity profile.

[0023] In one embodiment, the operation of changing the anode profile and the cathode profile may include the operation of identifying the first value and the second value based on changing the anode profile and the cathode profile.

[0024] For example, the first value and the second value may correspond to the initial values ​​of the capacity profile of the battery cell.

[0025] A battery diagnostic device and a battery diagnostic method according to one embodiment disclosed in this document can determine whether a battery cell is defective without disassembling the battery cell.

[0026] In addition, the battery diagnostic device and battery diagnostic method according to one embodiment disclosed in this document can more accurately determine whether a battery cell is defective by using both the positive profile and the negative profile.

[0027] In addition, various effects identified directly or indirectly through this document may be provided.

[0028] FIG. 1 is a block diagram showing a battery pack according to one embodiment disclosed in this document.

[0029] FIG. 2 is a block diagram showing the configuration of a battery diagnostic device according to one embodiment disclosed in this document.

[0030] FIG. 3 illustrates an example of a graph for showing the operation of a battery diagnostic device according to an embodiment disclosed in this document identifying a defective battery cell among a plurality of battery cells.

[0031] FIG. 4 illustrates an example of a graph showing the capacity profile of a battery cell according to an embodiment disclosed in this document.

[0032] FIG. 5 illustrates an example of a flowchart showing the operation performed by a battery diagnostic device according to an embodiment disclosed in this document.

[0033] FIG. 6 shows a computing system that executes a battery diagnostic method according to one embodiment disclosed in this document.

[0034] Some embodiments disclosed herein are described below with reference to the various embodiments of the accompanying drawings. However, this is not intended to limit the technology to specific embodiments and should be understood to include various modifications, equivalents, and / or alternatives to embodiments of the technology.

[0035] It should be noted that when assigning reference numerals to the components of each drawing, the same components are assigned the same reference numeral whenever possible, even if they are shown in different drawings. Furthermore, in describing the various embodiments disclosed in this document, if it is determined that a detailed description of related known configurations or functions would hinder understanding of the embodiments of the present invention, such detailed description is omitted. The singular form of a noun corresponding to an item may include one or more items unless the relevant context clearly indicates otherwise.

[0036] In describing the components of the embodiments of this document, terms such as first, second, A, B, (a), (b), etc., may be used. These terms are intended merely to distinguish the components from other components and do not limit the essence, order, or sequence of the components. Furthermore, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the embodiments disclosed in this document pertain. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0037] Additionally, in this disclosure, expressions of "greater than" or "less than" may be used to determine whether a specific condition is satisfied or fulfilled; however, this is merely for the purpose of expressing an example and does not exclude descriptions of "greater than" or "less than." Conditions described as "greater than" may be replaced with "greater than," conditions described as "less than" may be replaced with "less than," and conditions described as "greater than and less than" may be replaced with "greater than and less than." Furthermore, "A" to "B" below refer to at least one of the elements from A (including A) to B (including B).

[0038] In this document, each of the phrases such as "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.

[0039] In this document, where any component (e.g., 1) is referred to as being “connected,” “coupled,” or “joined” to another component (e.g., 2), with or without the terms “functionally” or “communicationally,” or where it is referred to as “coupled” or “connected,” it means that the component may be connected to the other component directly (e.g., via a wire), wirelessly, or through a third component.

[0040] The term “module” as used in the various embodiments of this document may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with terms such as logic, logic block, component, or circuit, for example. A module may be a component formed integrally, or a minimum unit of said component or a part thereof that performs one or more functions. For example, according to one embodiment, a module may be implemented in the form of an application-specific integrated circuit (ASIC).

[0041] Various embodiments of this document may be implemented as software (e.g., a program) comprising one or more instructions stored on a storage medium readable by a machine. For example, the processor of the machine may call at least one of the one or more instructions stored from the storage medium and execute it. This enables the machine to operate to perform at least one function according to the at least one called instruction. The one or more instructions may include code generated by a compiler or code that can be executed by an interpreter. The storage medium readable by a machine may be provided in the form of a non-transitory storage medium. Here, "non-transitory" simply means that the storage medium is a tangible device and does not contain a signal, and this term does not distinguish between cases where data is stored semi-permanently and cases where it is stored temporarily in the storage medium.

[0042] According to one embodiment, the method according to the various embodiments disclosed herein may be provided as included in a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a device-readable storage medium (e.g., compact disc read-only memory (CD-ROM)), or distributed online (e.g., download or upload) through an application store or directly between two user devices. In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily created on a device-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or a relay server.

[0043] According to various embodiments, each component (e.g., module or program) of the described components may include a singular or multiple entities, and some of the multiple entities may be separated and placed in other components. According to various embodiments, one or more of the aforementioned components or operations may be omitted, or one or more other components or operations may be added. Generally or additionally, multiple components (e.g., module or program) 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 they were performed by the corresponding component among the multiple components prior to integration.

[0044] According to various embodiments, operations performed by a module, program, or other component may be executed sequentially, in parallel, iteratively, or heuristically, or one or more of the operations may be executed in a different order, omitted, or one or more other operations may be added.

[0045]

[0046] FIG. 1 is a block diagram showing a battery pack according to one embodiment disclosed in this document.

[0047] Referring to FIG. 1, a battery control system including a battery pack (1) and a higher controller (2) included in a higher system according to one embodiment disclosed in this document is schematically shown.

[0048] As illustrated in FIG. 1, the battery pack (1) may include one or more battery cells (11) (or a plurality of battery cells), a switching unit (14) connected in series to the first terminal side and / or second terminal side of one or more battery cells (11) to control the flow of charging and discharging current of one or more 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.

[0049] In this case, the battery pack (1) may be equipped with one or more battery cells (11), a sensor (12), a switching unit (14), and / or a battery management system (20). For example, the first terminal may be the (+) terminal of one or more battery cells (11), and the second terminal may be the (-) terminal.

[0050] Here, the switching unit (14) is a device for controlling the current flow for charging or discharging one or more battery cells (11), and, for example, depending on the specifications of the battery pack (1), at least one relay, magnetic contactor, etc. may be used.

[0051] The battery management system (20) is an interface that receives values ​​of various parameters measured above, and may include a plurality of terminals and a circuit connected to these terminals to perform processing of the received values. Additionally, the battery management system (20) may control the ON / OFF of a switching unit (14), such as a relay or contactor, and may be connected to a battery cell (11) to monitor the status of one or more battery cells (11).

[0052] The upper controller (2) can transmit a control signal for one or more battery cells (11) to the battery management system (20). Accordingly, the operation of the battery management system (20) can be controlled based on the signal applied from the upper controller (2).

[0053] According to an embodiment, the battery management system (20) may include the battery diagnostic device (100) of FIG. 2. According to another embodiment, the battery management system (20) may be a different system from the battery diagnostic device (100) of FIG. 2. That is, the battery diagnostic device (100) of FIG. 2 may be included in the battery pack (1) or may be composed of another device outside the battery pack (1). For convenience of explanation, the description is based on the premise that the battery diagnostic device (100) is composed of another device outside the battery pack (1).

[0054]

[0055] FIG. 2 is a block diagram showing the configuration of a battery diagnostic device according to one embodiment disclosed in this document.

[0056] A battery diagnostic device (100) according to one embodiment may be implemented as a server for diagnosing battery cells, and specifically, may be implemented as various computing devices such as a workstation, cloud, data drive, and data station. In addition, the battery diagnostic device (100) may be implemented as one or more server devices that are physically or logically separated based on functions, detailed configurations of functions, or data, and may transmit and receive data and process the transmitted and received data through communication between each server device.

[0057] A battery diagnostic device (100) according to one embodiment may include at least one of a processor (110), a memory (120), or an interface (130). The processor (110), the memory (120), and the interface (130) may be electrically and / or operably coupled with each other by an electronic component including a communication bus. Hereinafter, operably coupled hardware may mean that a direct connection or an indirect connection between the hardware is established via wired or wireless means so that a second hardware is controlled by a first hardware among the hardware. Although illustrated based on different blocks, the embodiment is not limited thereto, and some of the hardware of FIG. 2 (e.g., at least a portion of the processor (110), the memory (120), and the communication circuit (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, GPIO (general purpose input and output), SPI (serial peripheral interface), MIPI (mobile industry processor interface), etc.

[0058] A processor (110) of a battery diagnostic device (100) according to one embodiment may include a hardware component for processing data based on one or more instructions. The hardware component 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, the processor (110) may have the structure of a multi-core processor including a dual core, a quad core, a hexa core, or an octa core.

[0059] A memory (120) of a battery diagnostic device (100) according to one embodiment may include a hardware component for storing data and / or instructions that are input and / or output to a processor (110). The memory (120) may include, for example, 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, compact disk, and embedded multi-media card (eMMC). For example, the memory (120) may be configured to store a voltage profile representing a voltage change with respect to a change in capacity of a battery cell comprising an LMFP (lithium manganese iron phosphate) material and / or an NCM (nickel, cobalt, manganese) material. For example, the LMFP material and / or NCM material may be included in the electrodes of the battery cell.

[0060] An interface (130) of a battery diagnostic device (100) according to one embodiment may be configured to generate various battery measurement values ​​from the battery. To this end, the interface (130) may include a measurement means such as a voltmeter, ammeter, and thermometer, and a communication circuit for establishing a communication link with an external device. The interface (130) may be configured to obtain a capacity profile representing the voltage for the capacity of the battery cell.

[0061] In one embodiment, the interface (130) may include a wireless communication unit and a wired communication unit to communicate with an external device.

[0062] In one embodiment, the wireless communication unit may include at least one of a short-range communication module and a long-range communication module.

[0063] For example, a short-range communication module can communicate with an external device adjacent to the battery diagnostic device (100) using a short-range communication method. Here, the short-range communication module may include at least one communication method among Bluetooth, Bluetooth Low Energy, infrared data association (IrDA), Zigbee, Wi-Fi, Wi-Fi Direct, Ultra Wideband (UWB), or near field communication (NFC).

[0064] For example, the remote communication module may include a communication module that performs various types of remote communication and may include a mobile communication unit. The mobile communication unit may be configured to transmit and receive wireless signals with at least one of a base station, an external terminal, or an external device on a mobile communication network. Additionally, the remote communication module may be used to communicate with an external device through a nearby access point (AP). The access point (AP) may connect the local network (LAN) to which the battery diagnostic device (100) is connected to a wide area network (WAN) to which the communication server is connected. Accordingly, the battery diagnostic device (100) can communicate with the external device (101) and the communication server via the wide area network (WAN).

[0065] In one embodiment, the wired communication unit may be configured to connect to a wired communication network and communicate with an external device through the wired communication network. For example, the wired communication unit may be configured to connect to a wired communication network via Ethernet (IEEE 802.3 technical standard) or to connect to a wired communication network via CAN communication and to transmit and receive data with an external device through the wired communication network.

[0066] A battery diagnostic device (100) according to one embodiment may include an input / output interface. It may provide a service that enables data transmission and reception by connecting an input device (not shown), such as a keyboard, mouse, or touch panel, and an output device (not shown), such as a display, to a processor (110).

[0067] A battery diagnostic device (100) according to one embodiment can obtain a capacity profile indicating a voltage for the capacity of a battery cell by using an interface (130). The battery diagnostic device (100) can obtain a positive profile indicating a voltage for the capacity of the positive electrode of the battery cell, and a negative profile indicating a voltage for the capacity of the negative electrode of the battery cell.

[0068] For example, the capacity profile may be referred to as a full-cell profile in terms of representing the voltage relative to the capacity of the entire battery cell, including the positive and negative electrodes.

[0069] For example, the positive profile (or positive capacity profile) may be referred to as a half-cell profile in relation to the positive portion of the battery cell. The negative profile (or negative capacity profile) may be referred to as a half-cell profile in relation to the negative portion of the battery cell.

[0070] For example, a capacity profile, a positive profile, and / or a negative profile can be obtained while charging or discharging the battery cell.

[0071] A battery diagnostic device (100) according to one embodiment can diagnose the condition of a battery cell based on a first value of a positive profile and a second value of a negative profile.

[0072] For example, the first value may include the initial value of the anode profile. The first value may be referred to as Pi (positive initial) in terms of including the initial value of the anode profile.

[0073] For example, the initial value of the anode profile can represent the voltage value of the anode profile for a specified SOC (e.g., 0%).

[0074] The second value may include the initial value of the cathode profile. The second value may be referred to as the Ni (negative initial) value in terms of including the initial value of the cathode profile.

[0075] For example, the initial value of the cathode profile may represent the voltage value of the cathode profile for a specified SOC (e.g., 0%).

[0076] For example, the first value (or the second value) may be configured to have a predetermined value distinguished for each charge / discharge cycle for a battery cell in a state of use (e.g., middle of life (MoL) state). For example, the first value (or the second value) may be configured to have a different value every 100 cycles. However, it is not limited thereto.

[0077]

[0078] A battery diagnostic device (100) according to one embodiment can diagnose the state of a battery cell as abnormal when the difference between a first value and a second value exceeds a specified range. For example, the battery diagnostic device (100) can diagnose the state of a battery cell as abnormal when the difference between a first value and a second value exceeds a threshold value.

[0079] For example, the difference between the first value and the second value may represent the loss of available lithium inventory of the battery cell.

[0080] For example, a battery cell diagnosed as being in an abnormal state may be referred to as a defective battery cell.

[0081] A battery diagnostic device (100) according to one embodiment may temporarily suspend the use of a preset area of ​​the state of charge (SOC) of a battery pack containing a battery cell when the state of the battery cell is diagnosed as abnormal. For example, when the battery diagnostic device (100) diagnoses the state of the battery cell as abnormal, it may change the SOC area for using the battery cell.

[0082] For example, a preset area may refer to the upper area of ​​the SOC, and the upper area may include an area between the maximum SOC of the battery cell and 90%. That is, the battery diagnostic device (100) can slow down the degradation of the battery cell by limiting the use of the upper area of ​​the battery cell.

[0083] For example, an abnormal condition may include an overhang defect where the difference between the area (or length) of the positive electrode of the battery cell and the area (or length) of the negative electrode of the battery cell exceeds a specified range.

[0084] For example, an overhang defect can represent a battery cell condition in which the area of ​​the positive electrode of the battery cell is larger than the area of ​​the negative electrode of the battery cell.

[0085] In other words, a defective battery cell may include an anode having an area larger than the area of ​​the negative electrode by a specified value. An overhang defect may indicate an assembly defect (or bonding defect) of the battery cell.

[0086] For example, an abnormal condition may include a condition in which the degradation level of a battery cell exceeds a specified degradation level. The degradation level may be determined based on the available lithium loss of the battery cell.

[0087] A battery diagnostic device (100) according to one embodiment may change the C-rate (current rate) (e.g., charge / discharge rate) for charging the battery cell when it diagnoses the condition of the battery cell as abnormal. For example, the battery diagnostic device (100) may lower the C-rate to a value lower than a preset value. For example, the battery diagnostic device (100) may charge the battery cell based on a low-rate charging (e.g., 0.33 C-rate). That is, by lowering the C-rate for charging the battery cell, the battery diagnostic device (100) may slow down the degradation of the battery cell.

[0088] A battery diagnostic device (100) according to one embodiment can obtain a simulation profile showing the difference between a positive profile and a negative profile.

[0089] For example, the battery diagnostic device (100) can change the positive profile and the negative profile so that the simulation profile corresponds to the capacity profile. For example, the battery diagnostic device (100) can identify a first value of the positive profile and a second value of the negative profile based on the change of the positive profile and the negative profile. In this case, the first value and the second value may correspond to the initial value of the capacity profile.

[0090] In one embodiment, the battery diagnostic device (100) can obtain one or more parameters based on changing the positive profile and the negative profile while mapping the simulation profile to the capacity profile.

[0091] For example, one or more parameters may include the difference between a reference positive profile (e.g., the positive profile of a battery cell in the BOL (beginning of life) state) and a modified positive profile. One or more parameters may include the difference between a reference negative profile (e.g., the negative profile of a battery cell in the BOL (beginning of life) state) and a modified negative profile.

[0092] For example, a battery diagnostic device (100) can diagnose the degree of degradation of a battery cell using one or more parameters. One or more parameters may indicate the degree to which the battery cell profile (e.g., positive profile or negative profile) has shrunk or shifted relative to a reference profile (e.g., reference positive profile or reference negative profile).

[0093] For example, a method in which a battery diagnostic device (100) diagnoses the degradation of a battery cell using one or more parameters representing the difference between a reference profile and a profile may be referred to as a battery quantification method in terms of quantifying the values ​​of one or more parameters. However, it is not limited thereto.

[0094] A battery diagnostic device (100) according to an embodiment as described above can diagnose the condition of a battery cell by using the difference between a first value of a positive profile and a second value of a negative profile. For example, by diagnosing the condition of a battery cell using both the first value and the second value, the battery diagnostic device (100) can determine the degree of degradation of the battery cell based on higher accuracy than diagnosing the condition of the battery cell using only the first value among the first value and the second value.

[0095] For example, cases where the first value changes may include cases where the resistance of the battery cell changes, or cases where the battery cell loading value, which represents the difference between the initial and final values ​​of the positive profile, changes. That is, diagnosing the degree of degradation of the battery cell using the first value may have lower accuracy than diagnosing the degree of degradation of the battery cell using the difference between the first value and the second value.

[0096] That is, the battery diagnostic device (100) can identify the degree of degradation of a battery cell with high accuracy based on the difference between a first value and a second value. In addition, the battery diagnostic device (100) can determine whether the battery cell is defective based on the difference between a first value and a second value.

[0097]

[0098] FIG. 3 illustrates an example of a graph for showing the operation of a battery diagnostic device according to an embodiment disclosed in this document identifying a defective battery cell among a plurality of battery cells. The battery diagnostic device (100) of FIG. 3 may be referenced to the battery diagnostic device (100) of FIG. 2.

[0099] Referring to FIG. 3, the graph (300) may include the difference between a first value and a second value of one or more battery cells (e.g., one or more battery cells (11) of FIG. 1) included in a battery pack (e.g., battery pack (1) of FIG. 1).

[0100] For example, a battery diagnostic device (100) can identify the difference between a first value and a second value by using the positive profile and negative profile of each of one or more battery cells included in a battery pack.

[0101] For example, the battery diagnostic device (100) can identify a defective battery cell (301) among one or more battery cells.

[0102] For example, the battery diagnostic device (100) can diagnose the condition of a battery cell as abnormal if the difference between a first value and a second value falls outside a specified range. A battery cell diagnosed as abnormal may include a defective battery cell.

[0103] For example, the battery diagnostic device (100) can diagnose the state of the battery cell as abnormal if the difference between the first value and the second value exceeds a threshold value (302).

[0104] For example, a defective battery cell (301) in which the difference between a first value and a second value exceeds a threshold value (302) may include a battery cell that has degenerated beyond a specified degree of degeneration. For example, a battery cell that has degenerated beyond a specified degree of degeneration may include a battery cell in which the available lithium loss amount exceeds a specified available lithium loss amount.

[0105] For example, a battery cell (e.g., a normal battery cell) in which the difference between the first value and the second value is less than the threshold value (302) may include a battery cell that has degenerated to a level less than the specified degree of degeneration.

[0106] A battery diagnostic device (100) according to one embodiment may temporarily stop using a preset area of ​​the SOC area of ​​a battery pack containing a defective battery cell (301) based on identifying a defective battery cell (301).

[0107] For example, the battery diagnostic device (100) can change the C-rate for charging a battery pack containing a defective battery cell (301).

[0108] For example, the battery diagnostic device (100) can provide information indicating the defective battery cell (301) to an external device based on identifying the defective battery cell (301).

[0109]

[0110] FIG. 4 illustrates an example of a graph showing the capacity profile of a battery cell according to an embodiment disclosed in this document. The battery diagnostic device (100) of FIG. 4 may include the battery diagnostic device (100) of FIG. 2.

[0111] Referring to FIG. 4, the graph (400) may include a capacity profile (410) representing a voltage for the capacity (or SOC) of a battery cell, a positive profile (420) representing a positive voltage for the positive capacity, a negative profile (430) representing a negative voltage for the negative capacity, and / or a simulation profile (440).

[0112] For example, a simulation profile (440) can be obtained based on the anode profile (420) and the cathode profile (430). The simulation profile (440) can represent the difference between the anode profile (420) and the cathode profile.

[0113] A battery diagnostic device (100) according to one embodiment can change the positive profile (420) and the negative profile (430) so that the simulation profile (440) corresponds to the capacity profile (410).

[0114] For example, the battery diagnostic device (100) can fit the simulation profile (440) to the capacity profile (410) based on curve fitting.

[0115] For example, the battery diagnostic device (100) can fit the simulation profile (440) to the capacity profile (410) by shrinking or shifting the positive profile (420) (or negative profile (430)) within the graph (400).

[0116] A battery diagnostic device (100) according to one embodiment can identify a first value (421) and a second value (431) based on changing the positive profile (420) and the negative profile (430).

[0117] For example, the first value (421) may correspond to the initial value (411) of the capacity profile (410). The second value (431) may correspond to the initial value (411) of the capacity profile (410).

[0118] For example, the initial value (411) of the capacity profile (410) can correspond to the point where the SOC is 0%.

[0119] A battery diagnostic device (100) according to one embodiment can diagnose the condition of a battery cell based on the difference between a first value (421) and a second value (431).

[0120] For example, the battery diagnostic device (100) can diagnose the condition of the battery cell as abnormal if the difference between the first value (421) and the second value (431) is outside the specified range.

[0121] For example, the battery diagnostic device (100) can diagnose the state of the battery cell as normal if the difference between the first value (421) and the second value (431) falls within a specified range.

[0122] A battery diagnostic device (100) according to an embodiment as described above can determine the condition of a battery cell by identifying the degree of degradation of the battery cell based on the difference between a first value (421) and a second value (431). The battery diagnostic device (100) can improve the accuracy of the identified degree of degradation using the first value (421) and the second value (431).

[0123]

[0124] FIG. 5 illustrates an example of a flowchart showing operations performed by a battery diagnostic device according to an embodiment disclosed in this document. Hereinafter, it is assumed that the battery diagnostic device (100) of FIG. 2 performs the process of FIG. 5. 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). Each of the operations of FIG. 5 may be performed sequentially, but is not necessarily performed sequentially. For example, the order of each of the operations may be changed, and at least two operations may be performed in parallel. In addition, the operation of the battery diagnostic device (100) may be performed by a Battery Management System (BMS) in a vehicle, as well as by various devices such as a server, cloud, charger, or charge / discharger.

[0125] In operation S510, a battery diagnostic device according to one embodiment can obtain a positive profile (e.g., positive profile (420) of FIG. 4) representing the voltage for the capacity of the positive electrode of a battery cell and a negative profile (e.g., negative profile (430) of FIG. 4) representing the voltage for the capacity of the negative electrode of a battery cell.

[0126] In one embodiment, the battery diagnostic device may change the positive profile and the negative profile so that a simulation profile (e.g., simulation profile (440) of FIG. 4) representing the difference between the positive profile and the negative profile corresponds to a capacity profile (e.g., capacity profile (410) of FIG. 4).

[0127] In one embodiment, the battery diagnostic device can identify a first value (e.g., the first value (421) in FIG. 4) and a second value (e.g., the second value (431) in FIG. 4) based on changing the positive profile and the negative profile.

[0128] In operation S520, a battery diagnostic device according to one embodiment can diagnose the condition of a battery cell based on a first value of a positive profile and a second value of a negative profile.

[0129] In one embodiment, the battery diagnostic device can diagnose the state of the battery cell based on the difference between a first value and a second value.

[0130] For example, the difference between the first value and the second value may represent the available lithium loss of the battery cell.

[0131] In one embodiment, the battery diagnostic device can diagnose the state of the battery cell as normal if the difference between the first value and the second value falls within a specified range.

[0132] For example, the battery diagnostic device can determine that the state of the battery cell is normal if the difference between the first value and the second value is less than a threshold value (e.g., the threshold value (302) of FIG. 3).

[0133] In one embodiment, the battery diagnostic device can diagnose the state of the battery cell as abnormal if the difference between the first value and the second value exceeds a specified range.

[0134] For example, a battery diagnostic device can determine that the state of a battery cell is abnormal if the difference between a first value and a second value exceeds a threshold value.

[0135] In one embodiment, when the battery diagnostic device diagnoses the state of the battery cell as abnormal, it may adjust the usage range of the battery cell's SOC or adjust the C-rate for charging the battery cell.

[0136]

[0137] FIG. 6 shows a computing system that executes a battery diagnostic method according to one embodiment disclosed in this document.

[0138] Referring to FIG. 6, a computing system (1000) according to one embodiment disclosed in this document may include an MCU (1010), a memory (1020), an input / output I / F (1030), and a communication I / F (1040).

[0139] The MCU (1010) may be a processor that executes various programs stored in memory (1020) (e.g., SOH calculation program, cell balancing target determination program, etc.), processes various data including SOC (state of charge), SOH (state of health), etc. of multiple battery cells through these programs, and performs the functions of the battery diagnostic device (100) described above. The MCU (1010) may be a BMS, a separate PC, or a cloud, but is not limited thereto.

[0140] The memory (1020) can store various programs for calculating the SOC of a battery cell and determining the degradation of a battery cell. In addition, the memory (1020) can store various data such as voltage data, capacity data, SOC data, and SOH data for each battery cell.

[0141] These memories (1020) may be provided in multiple quantities as needed. The memories (1020) may be volatile memories or non-volatile memories. As volatile memories, the memory (1020) may use RAM, DRAM, SRAM, etc. As non-volatile memories, the memory (1020) may use ROM, PROM, EAROM, EPROM, EEPROM, flash memory, etc. The examples of the memories (1020) listed above are merely examples and are not limited to these examples.

[0142] The input / output I / F (1030) can provide an interface that enables data transmission and reception between an input device (not shown), such as a keyboard, mouse, or touch panel, an output device (not shown), and an MCU (1010).

[0143] The communication I / F (1040) is configured to transmit and receive various data to and from a server and may be various devices capable of supporting wired or wireless communication. For example, through the communication I / F (1040), programs for calculating the SOH of a battery cell or determining a balancing target, or various data, can be transmitted and received from an external server provided separately.

[0144] As such, a battery diagnostic method according to one embodiment disclosed in this document can be recorded in memory (1020) and executed by an MCU (1010).

[0145] As described above, even though all components constituting the embodiments disclosed in this document have been described as being combined or operating 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 in one or more ways to operate.

[0146] Furthermore, terms such as "include," "compose," or "have" as described above, unless specifically stated otherwise, mean that the relevant component may be inherent; thus, they should be interpreted as allowing for the inclusion of additional components rather than excluding them. All terms, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the embodiments disclosed in this document pertain, unless otherwise defined. Commonly used terms, such as those defined in advance, should be interpreted in accordance with their contextual meanings in the relevant technology and, unless explicitly defined in this document, should not be interpreted in an ideal or overly formal sense.

[0147] The above description is merely an illustrative explanation of the technical concept disclosed in this document, and a person skilled in the art to which the embodiments disclosed in this document belong may make various modifications and variations within the scope of the essential characteristics of the embodiments disclosed in this document. Accordingly, the embodiments disclosed in this document are intended to explain, not limit, the technical concept of the embodiments disclosed in this document, and the scope of the technical concept disclosed in this document is not limited by these embodiments. The scope of protection of the technical concept disclosed in this document shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of this document.

Claims

1. An interface for obtaining a capacity profile representing the voltage for the capacity of a battery cell; and It includes at least one processor, The above-mentioned at least one processor is, A positive profile representing the voltage corresponding to the capacity of the positive electrode of the battery cell, and a negative profile representing the voltage corresponding to the capacity of the negative electrode of the battery cell are obtained, Configured to diagnose the state of the battery cell based on the first value of the positive profile and the second value of the negative profile. Battery diagnostic device.

2. In Claim 1, The above-mentioned at least one processor is, Configured to diagnose the state of the battery cell as abnormal when the difference between the first value and the second value exceeds a specified range, Battery diagnostic device.

3. In Claim 2, The above-mentioned at least one processor is, When the state of the battery cell is diagnosed as abnormal, the battery pack including the battery cell is configured to temporarily suspend the use of a preset area of ​​the state of charge (SOC) region. Battery diagnostic device.

4. In Claim 2, The above abnormal condition is, Including an overhang defect condition in which the difference between the area of ​​the positive electrode of the battery cell and the area of ​​the negative electrode of the battery cell exceeds a specified range, Battery diagnostic device.

5. In Claim 1, The above-mentioned at least one processor is, A configuration for changing the anode profile and the cathode profile such that a simulation profile representing the difference between the anode profile and the cathode profile corresponds to the capacity profile. Battery diagnostic device.

6. In Claim 5, The above-mentioned at least one processor is, Based on the modification of the anode profile and the cathode profile, configured to identify the first value and the second value, Battery diagnostic device.

7. In Claim 1, The above first value and the above second value Corresponding to the initial value of the capacity profile of the battery cell, Battery diagnostic device.

8. In Claim 1, The difference between the first value and the second value is Indicating the available lithium loss of the above battery cell, Battery diagnostic device.

9. An operation to obtain a positive profile representing a voltage corresponding to the capacity of the positive electrode of a battery cell, and a negative profile representing a voltage corresponding to the capacity of the negative electrode of the battery cell, and The method includes an operation of diagnosing the state of the battery cell based on the first value of the positive profile and the second value of the negative profile. Battery diagnostic method.

10. In Claim 9, The operation of diagnosing the condition of the above battery cell is, If the difference between the first value and the second value exceeds a specified range, the operation of diagnosing the state of the battery cell as an abnormal state is included. Battery diagnostic method.

11. In Claim 10, The operation of diagnosing the state of the above battery cell as an abnormal state is, When the state of the battery cell is diagnosed as abnormal, the operation includes temporarily suspending the use of a preset area among the state of charge (SOC) regions of the battery pack including the battery cell. Battery diagnostic method.

12. In Claim 10, The above abnormal condition is, Including an overhang defect condition in which the difference between the area of ​​the positive electrode of the battery cell and the area of ​​the negative electrode of the battery cell exceeds a specified range, Battery diagnostic method.

13. In Claim 9, The operation of obtaining the anode profile and the cathode profile above is, The method includes an operation to change the anode profile and the cathode profile so that a simulation profile representing the difference between the anode profile and the cathode profile corresponds to the capacity profile. Battery diagnostic method.

14. In Claim 13, The operation of changing the anode profile and the cathode profile is, Based on changing the anode profile and the cathode profile, the operation of identifying the first value and the second value, Battery diagnostic method.

15. In Claim 9, The above first value and the above second value Corresponding to the initial value of the capacity profile of the battery cell, Battery diagnostic method.

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