Battery diagnostic device and method therefor

Abstract

A battery diagnostic device according to an embodiment of the present specification comprises: a memory storing at least one instruction; and at least one processor for executing the at least one instruction, wherein the at least one processor may: on the basis of at least one of charging data of a battery cell, discharging data of the battery cell, or any combination thereof, calculate an open circuit voltage (OCV) for each first charged charge amount according to a charged charge amount indicating a charge amount charged in the battery cell; obtain a degradation index on the basis of the OCV for each first charged charge amount; and diagnose the state of the battery cell on the basis of the degradation index.

Description

Battery diagnostic device and method thereof

[0001] Cross-citation with related applications

[0002] This application claims the benefit of priority from Republic of Korea Patent Application No. 10-2024-0102814, filed August 2, 2024, the entire contents of which are incorporated herein by reference.

[0003] Technology field

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

[0005] Recently, research and development on secondary batteries has been actively underway. Here, secondary batteries are defined as rechargeable and dischargeable batteries, encompassing both conventional Ni / Cd and Ni / MH batteries, as well as more recent lithium-ion batteries. Recently, their use has expanded to include power sources for electric vehicles, attracting attention as a next-generation energy storage medium.

[0006] With the proliferation of various electronic devices driven by the Fourth Industrial Revolution, battery usage is rapidly increasing. Batteries are emerging as an essential energy source in various fields, including electric vehicles, portable electronic devices, and renewable energy storage systems. Consequently, the importance of battery condition diagnostic technology to improve battery performance and reliability is increasing.

[0007] In particular, technologies aimed at improving the accuracy of battery degradation indicator diagnosis, which indicates the extent of battery degradation, are attracting attention. If the accuracy of battery degradation indicator diagnosis is improved, problems that may arise due to battery degradation can be identified and prevented in advance.

[0008] According to embodiments disclosed in this document, it is an object to provide a battery diagnosis device and method that reduce resources required for battery diagnosis by reducing resources required for acquiring charge data and discharge data used for acquiring degradation indicators.

[0009] According to embodiments disclosed in this document, it is an object to provide a battery diagnostic device and method for identifying a degradation indicator while reducing the resources required to acquire charge data and discharge data used to acquire the degradation indicator.

[0010] According to embodiments disclosed in this document, it is an object to provide a battery diagnostic device and method for monitoring problems that may occur due to battery degradation by identifying degradation indicators.

[0011] The technical challenges of this document are not limited to the technical challenges mentioned above, and other technical challenges not mentioned will be clearly understood by those skilled in the art from the descriptions below.

[0012] A battery diagnostic device according to one embodiment of the present document may include a memory storing at least one instruction, and at least one processor executing the at least one instruction.

[0013] According to one embodiment, the at least one processor may obtain an open circuit voltage (OCV) according to a first charge amount, which indicates an amount of charge charged in the battery cell, based on at least one of charge data of the battery cell, discharge data of the battery cell, or a combination thereof, obtain a degradation index based on the open circuit voltage according to the first charge amount, and diagnose a state of the battery cell based on the degradation index.

[0014] According to one embodiment, the at least one processor may identify an open circuit voltage corresponding to the charge amount based on a) a first voltage value of the battery cell corresponding to the charge amount and included in the charge data, b) a first current value of the battery cell corresponding to the charge amount and included in the charge data, c) a second voltage value of the battery cell corresponding to the charge amount and included in the discharge data, and d) a second current value of the battery cell corresponding to the charge amount and included in the discharge data, and may identify an open circuit voltage for each of the first charge amounts based on the charge amount and the open circuit voltage.

[0015] According to one embodiment, the at least one processor may identify a voltage value of the battery cell corresponding to a case where the current value of the battery cell is less than a specified current value, based on a linear equation identified based on a relationship between the first current value and the first voltage value, and a relationship between the second current value and the second voltage value, and may identify an open circuit voltage corresponding to the charge amount based on the voltage value of the battery cell.

[0016] According to one embodiment, the at least one processor may obtain a parameter based on at least one of: i) an optimization algorithm, ii) an open circuit voltage according to a second charge amount of the battery cell in a middle of life (MOL) state indicated by the open circuit voltage according to the first charge amount, iii) an open circuit voltage according to a third charge amount of the battery cell in a beginning of life (BOL) state, iv) an open circuit potential (OCP) according to a charge amount of the battery cell in the BOL state, or v) any combination thereof, and obtain the degradation index based on the parameter.

[0017] According to one embodiment, the at least one processor may perform the optimization algorithm using a genetic algorithm (GA).

[0018] According to one embodiment, the at least one processor may obtain at least one of the charge data, the discharge data, or any combination thereof, based on a charge and discharge profile that charges the battery cell with a current value higher than a reference current a specific number of times less than a reference number of times from a lower limit charge amount higher than a first reference charge amount to an upper limit charge amount lower than a second reference charge amount, and discharges the battery cell with the current value a specific number of times from the upper limit charge amount to the lower limit charge amount.

[0019] In one embodiment, the degradation indicator may include a loss of lithium inventory (LLI) including a first parameter related to lithium loss in the middle of life (MOL) of the battery cell compared to the beginning of life (BOL), a first loss of active material (LAM) including a second parameter related to loss of active material of the negative plate in the middle of life (MOL) of the battery cell compared to the beginning of life (BOL), or a second loss of active material (LAM) including a third parameter related to loss of active material of the positive plate in the middle of life (MOL) of the battery cell compared to the beginning of life (BOL).

[0020] A battery diagnosis method according to an embodiment of the present document may include an operation of obtaining an open circuit voltage (OCV) according to a first charge amount indicating an amount of charge charged in the battery cell based on at least one of charge data of the battery cell, discharge data of the battery cell, or a combination thereof, an operation of obtaining a degradation index based on the open circuit voltage according to the first charge amount, and an operation of diagnosing a state of the battery cell based on the degradation index.

[0021] According to one embodiment, an operation of obtaining an open circuit voltage (OCV) according to a charge amount representing a charge amount charged in a battery cell based on at least one of charge data of a battery cell, discharge data of the battery cell, or a combination thereof may include an operation of identifying an open circuit voltage corresponding to the charge amount based on a) a first voltage value of the battery cell corresponding to the charge amount and included in the charge data, b) a first current value of the battery cell corresponding to the charge amount and included in the charge data, c) a second voltage value of the battery cell corresponding to the charge amount and included in the discharge data, and d) a second current value of the battery cell corresponding to the charge amount and included in the discharge data, and an operation of identifying an open circuit voltage according to the first charge amount based on the charge amount and the open circuit voltage.

[0022] According to one embodiment, the operation of identifying the open circuit voltage corresponding to the charged charge amount based on a) the first voltage value of the battery cell corresponding to the charged charge amount and included in the charging data, b) the first current value of the battery cell corresponding to the charged charge amount and included in the charging data, c) the second voltage value of the battery cell corresponding to the charged charge amount and included in the discharging data, and d) the second current value of the battery cell corresponding to the charged charge amount and included in the discharging data may include the operation of identifying the voltage value of the battery cell corresponding to the case where the current value of the battery cell is less than a specified current value according to a linear equation identified based on a relationship between the first current value and the first voltage value and a relationship between the second current value and the second voltage value, and the operation of identifying the open circuit voltage corresponding to the charged charge amount based on the voltage value of the battery cell.

[0023] According to one embodiment, the operation of obtaining the degradation index based on the open circuit voltage according to the first charge amount may include: an operation of obtaining a parameter based on at least one of: i) an optimization algorithm, ii) an open circuit voltage according to the second charge amount of the battery cell in the middle of life (MOL) state indicated by the open circuit voltage according to the first charge amount, iii) an open circuit voltage according to the third charge amount of the battery cell in the beginning of life (BOL) state, iv) an open circuit potential (OCP) according to the charge amount of the battery cell in the BOL state, or v) a combination thereof, and an operation of obtaining the degradation index based on the parameter.

[0024] According to one embodiment, the operation of obtaining the parameter based on at least one of i) the optimization algorithm, ii) the open circuit voltage for the second charge amount of the battery cell in the MOL state indicated by the open circuit voltage for the first charge amount, iii) the open circuit voltage for the third charge amount of the battery cell in the BOL state, iv) the open circuit potential for the charge amount of the battery cell in the BOL state, or v) any combination thereof may include an operation of performing the optimization algorithm using a genetic algorithm (GA).

[0025] According to one embodiment, the battery diagnosis method may further include an operation of charging the battery cell with a current value higher than a reference current a specific number of times less than a reference number from a lower limit charge amount higher than a first reference charge amount to an upper limit charge amount lower than a second reference charge amount, and an operation of obtaining at least one of the charge data, the discharge data, or any combination thereof, based on a charge and discharge profile that discharges the battery cell with the current value a specific number of times from the upper limit charge amount to the lower limit charge amount.

[0026] In one embodiment, the degradation indicator may include a loss of lithium inventory (LLI) including a first parameter related to lithium loss in the middle of life (MOL) of the battery cell compared to the beginning of life (BOL), or a first loss of active material (LAM) including a second parameter related to loss of active material of the negative plate in the middle of life (MOL) of the battery cell compared to the beginning of life (BOL), or a second loss of active material (LAM) including a third parameter related to loss of active material of the positive plate in the middle of life (MOL) of the battery cell compared to the beginning of life (BOL).

[0027] The present technology can reduce the resources required for battery diagnosis by reducing the resources required for acquiring charge data and discharge data for acquiring degradation indicators.

[0028] Additionally, the present technology can identify degradation indicators while reducing the resources required to acquire charge data and discharge data for acquiring degradation indicators.

[0029] Additionally, the present technology can monitor problems that may arise due to battery degradation by identifying degradation indicators.

[0030] In addition, various effects may be provided, either directly or indirectly, through this document.

[0031] FIG. 1 is a block diagram showing a battery pack in a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0032] FIG. 2 is a block diagram showing the configuration of a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0033] FIG. 3 illustrates examples of charge data and discharge data in a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0034] FIG. 4 illustrates an example of obtaining an open circuit voltage by first charge amount in a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0035] FIG. 5 illustrates an example of performing an optimization algorithm in a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0036] FIG. 6 illustrates an example of a degradation indicator in a battery diagnostic device and a battery diagnostic method according to one embodiment of the present document.

[0037] FIG. 7 illustrates an example of a flow of operations of a battery diagnostic device that diagnoses the state of a battery cell based on a degradation index in a battery diagnostic device and a battery diagnostic method according to one embodiment of the present document.

[0038] FIG. 8 is a block diagram showing the hardware configuration of a computing system that performs a battery diagnosis method in a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0039] Hereinafter, some embodiments disclosed in this document are described with reference to the accompanying drawings, which illustrate various embodiments of this document. However, this is not intended to limit the present technology to specific embodiments, and it should be understood that various modifications, equivalents, and / or alternatives of the embodiments of this technology are included.

[0040] When assigning reference numerals to components in each drawing, it should be noted that identical components are assigned the same numerals whenever possible, even if they are shown in different drawings. Furthermore, when describing various embodiments disclosed in this document, if a detailed description of a related known configuration or function is deemed to hinder understanding of the embodiments of the present invention, the detailed description will be omitted. The singular form of a noun corresponding to an item may include one or more items, unless the context clearly indicates otherwise.

[0041] 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 only intended to distinguish the components from other components, and the nature, order, or sequence of the components may not be limited by the terms. In addition, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiments disclosed in this document belong. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined in this application.

[0042] In addition, in the present disclosure, expressions such as "more than" or "less than" may be used to determine whether a specific condition is satisfied or fulfilled. However, this is merely a description for expressing an example and does not exclude descriptions such as "more than" or "less than." Conditions described as "more than" may be replaced with "more than," conditions described as "less than," and conditions described as "more than and less than" may be replaced with "more than and less than." In addition, hereinafter, "A" to "B" mean at least one of the elements from A (including A) to B (including B).

[0043] 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 that phrase, or all possible combinations thereof.

[0044] In this document, when a component (e.g., a first component) is referred to as being “connected,” “coupled,” or “connected,” with or without the terms “functionally” or “communicatively,” or is referred to as being “coupled” or “connected,” it means that the component can be connected to the other component directly (e.g., wired), wirelessly, or through a third component.

[0045] According to one embodiment, the method according to the various embodiments disclosed in the present document may be provided as included in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., compact disc read-only memory (CD-ROM)), or may be distributed online (e.g., downloaded or uploaded) 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 generated in a machine-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or an intermediary server.

[0046] According to various embodiments, each component (e.g., a module or a program) of the described components may include one or more entities, and some of the entities may be separated and placed in other components. According to various embodiments, one or more components or operations of the aforementioned components may be omitted, or one or more other components or operations may be added. Alternatively or additionally, a plurality of components (e.g., a module or a program) may be integrated into a single component. In such a case, the integrated component may perform one or more functions of each of the plurality of components identically or similarly to those performed by the corresponding component among the plurality of components prior to integration. According to various embodiments, the 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.

[0047] Hereinafter, embodiments of the present document will be described in detail with reference to FIGS. 1 to 8.

[0048] FIG. 1 is a block diagram showing a battery pack in a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0049] Referring to FIG. 1, a battery pack (1) may include a battery unit (12), a sensor unit (14), a switching unit (16), and a battery management system (BMS) (20). At this time, the battery pack (1) may be equipped with a plurality of battery units (12), sensor units (14), switching units (16), and battery management systems (20).

[0050] According to one embodiment, the battery unit (12) can supply power to a target device (not shown). To this end, the battery unit (12) can be electrically connected to the target device. Here, the target device can include an electrical, electronic, or mechanical device that operates by receiving power from the battery pack (1). For example, the target device can be, but is not limited to, an electric vehicle (EV) or an energy storage system (ESS).

[0051] According to one embodiment, the battery unit (12) may include at least one battery cell (10) that can be charged and discharged. Here, the battery cell (10) may be a basic unit of a battery cell that can be used by charging and discharging electric energy. For example, the battery cell (10) may be a lithium-ion (Li-ion) battery, a lithium-ion polymer (Li-ion polymer) battery, a nickel-cadmium (Ni-Cd) battery, a nickel-metal hydride (Ni-MH) battery, etc., but may not be limited thereto.

[0052] According to one embodiment, a plurality of battery units (12) may be connected in series or parallel. For example, the battery unit (12) may be a battery module, a battery bank, or a collection of battery cells (cell-to-pack structure).

[0053] According to one embodiment, the sensor unit (14) can obtain information related to the battery unit (12). According to one embodiment, the sensor unit (14) can obtain values ​​(or information) related to the state of each of the battery unit (12) or battery cells (10). In one embodiment, the values ​​related to the state may include one or more values ​​for voltage, current, resistance, state of charge (SOC), state of health (SOH), or temperature of the battery cell, or a combination thereof.

[0054] According to one embodiment, the sensor unit (14) can provide information on each of the plurality of battery units (12) to the battery management system (20).

[0055] According to one embodiment, the switching unit (16) may include a device for controlling the current flow for charging or discharging the battery unit (12). For example, the switching unit (16) may include at least one relay and / or magnetic contactor, etc., depending on the specifications of the battery pack (1).

[0056] According to one embodiment, a battery management system (BMS) (20) may monitor voltage, current, temperature, etc. of the battery pack (1) to control or manage the battery pack (1) to prevent overcharge, overdischarge, etc. For example, the battery management system (20) may include a plurality of terminals as an interface for receiving values ​​measured from the various parameters described above, and a circuit connected to these terminals to process the input values. In addition, the battery management system (20) may control the sensor unit (14) and / or the switching unit (16). For example, the battery management system (20) may be connected to a plurality of battery units (12) to monitor the status of each of the plurality of battery units (12) and control ON / OFF of a relay or a contactor, etc.

[0057] According to one embodiment, the operation of the battery management system (20) may be performed by a battery management system (BMS) in the vehicle, as well as by various devices such as a server, cloud, charger, or discharger.

[0058] The upper controller (2) can transmit control signals for multiple battery units (12) to the battery management system (20). Accordingly, the battery management system (20) can be controlled for operation based on signals received from the upper controller (2).

[0059] According to one embodiment, the battery management system (20) may include the battery diagnostic device (201) of FIG. 2. According to another embodiment, the battery management system (20) may be a different system from the battery diagnostic device (201) of FIG. 2. That is, the diagnostic device (201) of FIG. 2 may be included in the battery pack (1) or may be configured as another device external to the battery pack (1). For convenience of explanation, the following description will be made on the assumption that the battery diagnostic device (201) is configured as another device external to the battery pack (1). In addition, the operation of the battery diagnostic device (201) below may be performed by an in-vehicle BMS (battery management system), as well as by various devices such as a server, a cloud, a charger, or a discharger.

[0060] FIG. 2 is a block diagram showing the configuration of a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0061] Referring to FIG. 2, the battery diagnostic device (201) may include a memory (203) and at least one processor (205). The memory (203) may include at least one instruction. The at least one processor (205) may execute at least one instruction.

[0062] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can perform a reference performance test (RPT) to diagnose the state of a battery cell (e.g., battery cell (10) of FIG. 1).

[0063] According to one embodiment, at least one processor (205) of a battery diagnostic device (201) may perform a reference performance test (RPT) while charging or discharging a battery cell and obtain electrical parameter values ​​(e.g., current, voltage, state of charge (SOC)) of the battery cell. The state of charge may represent the amount of charge charged in the battery cell.

[0064] According to one embodiment, at least one processor (205) of the battery diagnosis device (201) can obtain charge data and discharge data based on a charge and discharge profile that charges a battery cell a specific number of times less than a reference number from a lower limit charge amount that is higher than a first reference charge amount to an upper limit charge amount that is lower than a second reference charge amount, and discharges the battery cell a specific number of times less than a reference number from the upper limit charge amount to the lower limit charge amount. At least one processor (205) of the battery diagnosis device (201) can diagnose a state of a battery cell based on the charge data and the discharge data. In addition, at least one processor (205) of the battery diagnosis device (201) can measure an open circuit voltage even through a current greater than a specified current value. According to one embodiment, the time and electrical resources consumed by the battery diagnosis device (201) to diagnose a state of a battery cell may be less than the time and electrical resources consumed by a conventional battery diagnosis device to diagnose a state of a battery cell.

[0065] Open circuit voltage can represent the voltage of a battery cell when it is not connected to an external circuit and no current is flowing.

[0066] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can obtain an open circuit voltage for each charge amount of a battery cell in a middle of life (MOL) state based on charge data and discharge data.

[0067] According to one embodiment, at least one processor (205) of a battery diagnostic device (201) may obtain a degradation index (e.g., a first LAM, which is a loss of active material (LAM) of a negative plate, a second LAM, which is a LAM of a positive plate, and a loss of lithium inventory (LLI)) based on an open circuit voltage by charge amount of a battery cell in a middle of life (MOL) state, an open circuit voltage by charge amount of a battery cell in a beginning of life (BOL) state, and an open circuit potential (OCP) by charge amount of a battery cell in a BOL state.

[0068] The first LAM may include a second parameter related to the loss of active material in the negative plate at the MOL versus the BOL of the battery cell. The second LAM may include a third parameter related to the loss of active material in the positive plate at the MOL versus the BOL of the battery cell. The LLI may include a first parameter related to the loss of lithium in the MOL versus the BOL of the battery cell.

[0069] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can obtain a final degradation index by correcting the obtained degradation index.

[0070] The method of obtaining the final degradation index by efficiently using the temporal and electrical resources of the battery diagnostic device (201) is described below in FIGS. 3 to 6.

[0071] FIG. 3 illustrates examples of charge data and discharge data in a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0072] Referring to FIG. 3, a table (301) may represent charge data of a battery cell (e.g., battery cell (10) of FIG. 1) and discharge data of the battery cell obtained by a battery diagnosis device (201) according to one embodiment. A graph (311) may represent an open circuit voltage according to a charge amount identified based on the table (301). A first line (313) of the graph (311) may represent an open circuit voltage identified based on the charge data. A second line (315) may represent an open circuit voltage identified based on the discharge data.

[0073] In one embodiment, the first line (313) indicating the open circuit voltage identified based on the charge data and the second line (315) indicating the open circuit voltage identified based on the discharge data may not match.

[0074] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can separate the charge data and discharge data included in the table (301) according to the charge amount so as to identify one open circuit voltage according to the charge amount.

[0075] For example, when at least one processor (205) of the battery diagnostic device (201) identifies charging data and discharging data based on a profile in which charging and discharging are performed once, two voltage values ​​and two current values ​​can be obtained according to a specific charging charge amount.

[0076] FIG. 4 illustrates an example of obtaining an open circuit voltage by first charge amount in a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0077] Referring to FIG. 4, a first graph (401) may include a voltage graph for a current corresponding to a first charge amount. A second graph (409) may include a voltage graph for a current corresponding to a second charge amount. A third graph (411) may include a voltage graph for a current corresponding to a third charge amount. A fourth graph (413) may include a voltage graph for a current corresponding to a fourth charge amount. A fifth graph (421) may include an open circuit voltage graph according to a charge amount. A first line (423) of the fifth graph (421) may represent an open circuit voltage identified based on charge data. A second line (425) of the fifth graph (421) may represent an open circuit voltage identified based on charge data and discharge data. The third line (427) of the fifth graph (421) may represent the open circuit voltage identified based on the discharge data.

[0078] According to one embodiment, the first graph (401) may correspond to the first charge amount, the second graph (409) may correspond to the second charge amount, the third graph (411) may correspond to the third charge amount, and the fourth graph (413) may correspond to the fourth charge amount.

[0079] According to one embodiment, at least one processor (205) of the battery diagnosis device (201) identifies an open circuit voltage corresponding to the charge amount based on a) a first voltage value (e.g., a voltage value corresponding to the second point (407)) of a battery cell corresponding to a charge amount (e.g., a first charge amount, a second charge amount, a third charge amount, a fourth charge amount) and included in the charge data, b) a first current value (e.g., a current value corresponding to the second point (407)) of a battery cell corresponding to the charge amount and included in the charge data, c) a second voltage value (e.g., a voltage value corresponding to the first point (403)) of a battery cell corresponding to the charge amount and included in the discharge data, and d) a second current value (e.g., a current value corresponding to the first point (403)) of a battery cell corresponding to the charge amount and included in the discharge data, and based on the charge amount and the open circuit voltage, an open circuit voltage corresponding to each charge amount is identified. Circuit voltage can be identified.

[0080] According to one embodiment, in the first graph (401), the first point (403) may correspond to a second current value of a battery cell (e.g., battery cell (10) of FIG. 1) corresponding to the first charge amount and included in the discharge data, and a second voltage value of the battery cell corresponding to the first charge amount and included in the discharge data.

[0081] According to one embodiment, in the first graph (401), the second point (407) may correspond to a first current value of a battery cell corresponding to a first charge amount and included in the charge data, and a first voltage value of a battery cell corresponding to a first charge amount and included in the discharge data.

[0082] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can identify a regression equation identified based on the first point (403) and the second point (407). At least one processor (205) of the battery diagnostic device (201) can identify a regression line (405) based on the linear equation that is the regression equation. In other words, the regression line (405) can represent a linear equation identified based on a relationship between the first current value and the first voltage value, and a relationship between the second current value and the second voltage value.

[0083] According to one embodiment, at least one processor (205) of the battery diagnosis device (201) can identify a voltage value of a battery cell corresponding to a case where the current value of the battery cell is less than a specified current value (e.g., when the current value of the battery cell is about 0 A (ampere)) based on the regression line (405). At least one processor (205) of the battery diagnosis device (201) can identify an open circuit voltage according to a first charge amount based on the voltage value of the battery cell corresponding to a case where the current value of the battery cell is less than a specified current value.

[0084] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can identify an open circuit voltage according to a second charge amount based on the second graph (409).

[0085] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can identify an open circuit voltage according to a third charge amount based on the third graph (411).

[0086] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can identify an open circuit voltage according to a fourth charge amount based on the fourth graph (413).

[0087] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can identify an open circuit voltage according to a charge amount, such as a second line (425) of the fifth graph (421), based on an open circuit voltage according to a first charge amount, an open circuit voltage according to a second charge amount, an open circuit voltage according to a third charge amount, and an open circuit voltage according to a fourth charge amount.

[0088] FIG. 5 illustrates an example of performing an optimization algorithm in a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0089] Referring to FIG. 5, a graph (501) may represent a voltage for a charge amount of a battery cell (e.g., battery cell (10) of FIG. 1). The positive potential (503) may include the positive potential of the battery cell estimated at the MOL point in time. The negative potential (505) may include the negative potential of the battery cell estimated at the MOL point in time. The first open circuit voltage (507) may include the open circuit voltage of the battery cell identified at the MOL point in time. The second open circuit voltage (509) may represent the open circuit voltage of the battery cell identified based on the positive potential (503) and the negative potential (505). For example, the second open circuit voltage (509) may represent the difference between the positive potential (503) and the negative potential (505).

[0090] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) may obtain a parameter based on at least one of: i) an optimization algorithm (e.g., a genetic algorithm (GA)), ii) an open circuit voltage according to a second charge amount of a battery cell in a middle of life (MOL) state indicated by an open circuit voltage according to a first charge amount, iii) an open circuit voltage according to a third charge amount of a battery cell in a beginning of life (BOL) state, iv) an open circuit potential (OCP) according to a charge amount of a battery cell in a BOL state, or v) a combination thereof, and obtain a degradation index based on the parameter.

[0091] At least one processor (205) of the battery diagnosis device (201) according to one embodiment can obtain each of the positive potential (503) and the negative potential (505) by using the positive potential at the BOL point and the negative potential at the BOL point. For example, at least one processor (205) of the battery diagnosis device (201) can obtain each of the positive potential (503) and the negative potential (505) by applying different shrinkage rates to each of the charge amount regions. That is, at least one processor (205) of the battery diagnosis device (201) can obtain a parameter corresponding to each of the charge amount regions.

[0092] At least one processor (205) of a battery diagnostic device (201) according to an embodiment can calculate a deviation between a second open circuit voltage (509) in a BOL state and a first open circuit voltage (507) in a MOL state in each charge charge section of a battery cell. The processor according to an embodiment can calculate a parameter that minimizes the deviation in the entire charge charge section.

[0093] When the deviation is minimized, at least one processor (205) of the battery diagnostic device (201) can obtain a second open circuit voltage (509) that is substantially the same as the first open circuit voltage (507). That is, at least one processor (205) of the battery diagnostic device (201) can perform optimization for parameters by identifying the positive potential (503) and the negative potential (505) for matching the first open circuit voltage (507) and the second open circuit voltage (509).

[0094] In one embodiment, at least one processor (205) of the battery diagnostic device (201) can obtain a positive potential (503) and a negative potential (505) corresponding to the second open circuit voltage (509) obtained at the MOL point in time by obtaining a second open circuit voltage (509) that is substantially equal to the first open circuit voltage (507).

[0095] For example, at least one processor (205) of the battery diagnostic device (201) can compare the positive potential (503) and the negative potential (505) with the positive potential and the negative potential obtained at the BOL point in time, respectively, to obtain the shrinkage ratio for the positive potential, the mobility for the positive potential, the shrinkage ratio for the negative potential, and / or the mobility for the negative potential.

[0096] At least one processor (205) of a battery diagnostic device (201) according to one embodiment can diagnose the state of a battery cell using parameters. For example, at least one processor (205) of the battery diagnostic device (201) can obtain a degradation index using mathematical expressions 1 to 3.

[0097]

[0098] Referring to mathematical expression 1, LAMn (loss of active material negative) can indicate the degree to which the active material of the battery contained in the negative electrode is lost. can represent the shrinkage of the cathode potential measured at the BOL point. For example, can be 1, but is not limited to this. can represent the shrinkage ratio of the estimated cathode potential at the MOL point. The shrinkage ratio of the estimated cathode potential at the MOL point can be included in the parameters optimized by the specified algorithm.

[0099]

[0100] Referring to mathematical expression 2, LAMp (loss of active material positive) can indicate the degree to which the active material of the battery contained in the positive electrode is lost. can represent the shrinkage of the anode potential measured at the BOL point. For example, can be 1, but is not limited to this. can represent the shrinkage rate of the estimated anode potential at the MOL point in time. The shrinkage rate of the estimated anode potential at the MOL point in time can be included in the parameters optimized by the specified algorithm.

[0101]

[0102] Referring to mathematical expression 3, LLI can represent the capacity loss of lithium contained in a battery cell. can represent the mobility of the estimated cathode potential at the MOL point. can represent the mobility of the estimated bipolar potential at the MOL point. can represent the mobility of the cathode potential obtained at the BOL point. can represent the mobility of the anode potential obtained at the BOL point.

[0103] For example, and may be included in the parameters optimized by the specified algorithm. and may be included in the battery data in BOL state.

[0104] At least one processor (205) of a battery diagnosis device (201) according to an embodiment can diagnose the state of a battery cell using LAMn, LAMp, and / or LLI. For example, at least one processor (205) of the battery diagnosis device (201) can provide a diagnosis result diagnosing the state of a battery cell. For example, at least one processor (205) of the battery diagnosis device (201) can provide the diagnosis result to a user by transmitting the diagnosis result to an external electronic device (e.g., a server). However, the present invention is not limited thereto.

[0105] FIG. 6 illustrates an example of a degradation indicator in a battery diagnostic device and a battery diagnostic method according to one embodiment of the present document.

[0106] Referring to FIG. 6, a first graph (601) may include points (603) representing a relationship between an experimentally obtained LAM of a negative electrode plate (e.g., LAMn2) and a LAM of a negative electrode plate identified through an optimization algorithm (e.g., LAMn1), and a first line (605) representing a regression equation according to the points (603).

[0107] The second graph (611) may include points (613) representing the relationship between the LAM of the bipolar plate obtained experimentally (e.g., LAMp2) and the LAM of the bipolar plate identified through the optimization algorithm (e.g., LAMp1), and a second line (615) representing a regression equation according to the points (613).

[0108] The third graph (621) may include points (623) representing the relationship between the LLI of the bipolar plate obtained experimentally (e.g., LLI2) and the LLI of the bipolar plate identified through the optimization algorithm (e.g., LLI1), and a third line (625) representing a regression equation according to the points (623).

[0109] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can correct the LAM of the identified negative plate through an optimization algorithm to a final LAM of the negative plate (e.g., a first LAM) based on the preset relationship identified according to the first line (605).

[0110] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can correct the LAM of the positive plate identified through an optimization algorithm to a final LAM of the positive plate (e.g., a second LAM) based on the preset relationship identified according to the second line (615).

[0111] According to one embodiment, at least one processor (205) of the battery diagnostic device (201) can correct the identified LLI to the final LLI of the negative plate through an optimization algorithm based on the preset relationship identified according to the third line (625).

[0112] FIG. 7 illustrates an example of a flow of operations of a battery diagnostic device that diagnoses the state of a battery cell based on a degradation index in a battery diagnostic device and a battery diagnostic method according to one embodiment of the present document.

[0113] Hereinafter, it is assumed that the battery diagnostic device (201) of FIG. 2 performs the process of FIG. 7. In addition, in the description of FIG. 7, the operations described as being performed by the battery diagnostic device can be understood as being performed by at least one processor (205) of the battery diagnostic device (201) of FIG. 2.

[0114] Referring to FIG. 7, in a first operation (701), at least one processor (205) of a battery diagnostic device (201) according to an embodiment may obtain an open circuit voltage according to a first charge amount according to a charge amount representing the charge amount charged in a battery cell, based on at least one of charge data of a battery cell, discharge data of a battery cell, or any combination thereof.

[0115] In the second operation (703), at least one processor (205) of the battery diagnostic device (201) according to one embodiment can obtain a degradation index based on the open circuit voltage for each first charge amount.

[0116] In a third operation (705), at least one processor (205) of a battery diagnostic device (201) according to one embodiment can diagnose the state of a battery cell based on a degradation indicator.

[0117] FIG. 8 is a block diagram showing the hardware configuration of a computing system that performs a battery diagnosis method in a battery diagnosis device and a battery diagnosis method according to one embodiment of the present document.

[0118] Referring to FIG. 8, a computing system (800) according to an embodiment disclosed in the present document may include an MCU (810), a memory (820), an input / output I / F (830), and a communication I / F (840).

[0119] The MCU (810) may be at least one processor that executes various programs stored in the memory (820) (e.g., a battery cell data collection program, a graph generation program, a data analysis program, a data decomposition algorithm, a normalization program, a battery cell diagnosis program, etc.), processes various information including battery cell characteristic data and latent variables through these programs, and performs the functions of the battery diagnosis device (201) shown in the above-described FIGS. 2 to 5.

[0120] The memory (820) can store various programs such as a battery cell data collection program, a graph generation program, a data analysis program, a data decomposition algorithm, a normalization program, and a battery cell diagnosis program.

[0121] Such memories (820) may be provided in multiples as needed. The memories (820) may be volatile memories or non-volatile memories. As volatile memories (820), RAM, DRAM, SRAM, etc. may be used. As non-volatile memories (820), ROM, PROM, EAROM, EPROM, EEPROM, flash memories, etc. may be used. The examples of the memories (820) listed above are merely examples and are not limited to these examples.

[0122] The input / output I / F (830) can provide an interface that enables data transmission and reception between an input device (not shown) such as a keyboard, mouse, or touch panel, and an output device (not shown) such as a display and the MCU (810).

[0123] The communication I / F (840) is a component capable of transmitting and receiving various data with the server, and may be any device capable of supporting wired or wireless communication. For example, the diagnostic device (201) can transmit and receive various types of information, including battery cell shape models, from a separately provided external server via the communication I / F (840).

[0124] In this way, a computer program according to an embodiment disclosed in this document may be implemented as a module that performs each function illustrated in FIG. 2, for example, by being recorded in a memory (820) and processed by an MCU (810).

[0125] In the above, although all components constituting the embodiments disclosed in this document have been described as being combined or operating in combination as one, the embodiments disclosed in this document are not necessarily limited to such embodiments. That is, within the scope of the purpose of the embodiments disclosed in this document, all of the components may be selectively combined and operated one or more times.

[0126] In addition, terms such as "include," "comprise," or "have" described above, unless specifically stated to the contrary, should be interpreted to imply the inclusion of the corresponding component, and thus should not be interpreted to exclude other components, but rather to include other components. All terms, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiments disclosed in this document belong, unless otherwise defined. Commonly used terms, such as terms defined in a dictionary, should be interpreted to be consistent with the contextual meaning of the relevant technology, and shall not be interpreted in an idealized or overly formal sense, unless explicitly defined in this document.

[0127] The foregoing disclosure outlines features of several embodiments to enable those skilled in the art to better understand the aspects of the present disclosure. Those skilled in the art will readily appreciate that the present disclosure can be readily used as a basis for designing or modifying other structures to achieve the same purposes or advantages of the embodiments introduced herein. Furthermore, those skilled in the art will recognize that such equivalent structures do not depart from the scope of the present disclosure, and that various changes, substitutions, and modifications can be made herein without departing from the scope of the present disclosure.

Claims

1. Memory that stores at least one instruction; and comprising at least one processor executing at least one instruction; At least one processor, Based on at least one of charge data of a battery cell, discharge data of the battery cell, or any combination thereof, an open circuit voltage (OCV) for each first charge amount according to the charge amount representing the amount of charge charged in the battery cell is obtained, Based on the open circuit voltage for each of the first charge amounts, a degradation index is obtained, configured to diagnose the condition of the battery cell based on the above degradation indicator, Battery diagnostic device.

2. In claim 1, At least one processor, a) a first voltage value of the battery cell corresponding to the charged charge amount and included in the charging data, b) a first current value of the battery cell corresponding to the charged charge amount and included in the charging data, c) a second voltage value of the battery cell corresponding to the charged charge amount and included in the discharging data, and d) a second current value of the battery cell corresponding to the charged charge amount and included in the discharging data, identifying an open circuit voltage corresponding to the charged charge amount, Based on the above charge amount and the open circuit voltage, configured to identify the open circuit voltage for each of the first charge amounts, Battery diagnostic device.

3. In claim 2, At least one processor, Identifying a voltage value of the battery cell corresponding to a case where the current value of the battery cell is less than a specified current value according to a linear equation identified based on the relationship between the first current value and the first voltage value and the relationship between the second current value and the second voltage value, Based on the voltage value of the battery cell, configured to identify an open circuit voltage corresponding to the charged amount, Battery diagnostic device.

4. In claim 1, At least one processor, i) an optimization algorithm, ii) an open circuit voltage according to a second charge amount of the battery cell in the middle of life (MOL) state indicated by the open circuit voltage according to the first charge amount, iii) an open circuit voltage according to a third charge amount of the battery cell in the beginning of life (BOL) state, iv) an open circuit potential (OCP) according to a charge amount of the battery cell in the BOL state, or v) at least one of a combination thereof, to obtain a parameter, Based on the above parameters, configured to obtain the above degradation index, Battery diagnostic device.

5. In claim 4, At least one processor, It is configured to perform the above optimization algorithm using a genetic algorithm (GA). Battery diagnostic device.

6. In claim 1, At least one processor, Based on a charge and discharge profile that charges the battery cell with a current value higher than the reference current a specific number of times less than the reference number from a lower limit charge amount higher than the first reference charge amount to an upper limit charge amount lower than the second reference charge amount, and discharges the battery cell with the current value a specific number of times from the upper limit charge amount to the lower limit charge amount, configured to acquire at least one of the charging data, the discharging data, or any combination thereof; Battery diagnostic device.

7. In claim 1, The above deterioration indicators are, Including a loss of lithium inventory (LLI) including a first parameter related to lithium loss in the middle of life (MOL) compared to the beginning of life (BOL) of the battery cell, or A first LAM (loss of active material; LAM) comprising a second parameter related to the loss of active material of the negative plate in the MOL versus BOL of the battery cell, or A second LAM (loss of active material; LAM) is configured to include a third parameter related to the loss of active material of the positive electrode plate in the MOL versus BOL of the battery cell. Battery diagnostic device.

8. An operation of obtaining an open circuit voltage (OCV) according to a first charge amount, which represents an amount of charge charged in the battery cell, based on at least one of charge data of the battery cell, discharge data of the battery cell, or any combination thereof; An operation of obtaining a degradation index based on the open circuit voltage for each of the first charging charges; and Including an operation of diagnosing the state of the battery cell based on the above degradation indicator, How to diagnose a battery.

9. In claim 8, An operation of obtaining an open circuit voltage (OCV) for each first charge amount according to a charge amount representing the amount of charge charged in the battery cell based on at least one of charge data of the battery cell, discharge data of the battery cell, or any combination thereof, An operation of identifying an open circuit voltage corresponding to the charge amount based on a) a first voltage value of the battery cell corresponding to the charge amount and included in the charge data, b) a first current value of the battery cell corresponding to the charge amount and included in the charge data, c) a second voltage value of the battery cell corresponding to the charge amount and included in the discharge data, and d) a second current value of the battery cell corresponding to the charge amount and included in the discharge data; and An operation of identifying an open circuit voltage for each of the first charged charges based on the charged charge amount and the open circuit voltage, How to diagnose a battery.

10. In claim 9, An operation of identifying the open circuit voltage corresponding to the charge amount based on a) the first voltage value of the battery cell corresponding to the charge amount and included in the charge data, b) the first current value of the battery cell corresponding to the charge amount and included in the charge data, c) the second voltage value of the battery cell corresponding to the charge amount and included in the discharge data, and d) the second current value of the battery cell corresponding to the charge amount and included in the discharge data, An operation of identifying a voltage value of the battery cell corresponding to a case where the current value of the battery cell is less than a specified current value, according to a linear equation identified based on a relationship between the first current value and the first voltage value, and a relationship between the second current value and the second voltage value; and An operation of identifying an open circuit voltage corresponding to the charge amount based on the voltage value of the battery cell, How to diagnose a battery.

11. In claim 8, Based on the open circuit voltage for each of the first charge amounts, the operation of obtaining the degradation index is as follows: An operation of obtaining a parameter based on at least one of: i) an optimization algorithm, ii) an open circuit voltage according to a second charge amount of the battery cell in a middle of life (MOL) state indicated by the open circuit voltage according to the first charge amount, iii) an open circuit voltage according to a third charge amount of the battery cell in a beginning of life (BOL) state, iv) an open circuit potential (OCP) according to a charge amount of the battery cell in the BOL state, or v) a combination thereof; and Based on the above parameters, including an operation of obtaining the degradation index, How to diagnose a battery.

12. In claim 11, The operation of obtaining the parameter based on at least one of i) the optimization algorithm, ii) the open circuit voltage for the second charge amount of the battery cell in the MOL state indicated by the open circuit voltage for the first charge amount, iii) the open circuit voltage for the third charge amount of the battery cell in the BOL state, iv) the open circuit potential for the charge amount of the battery cell in the BOL state, or v) any combination thereof. Including an operation of performing the above optimization algorithm using a genetic algorithm (GA). How to diagnose a battery.

13. In claim 8, An operation of charging the battery cell with a current value higher than a reference current a specific number of times less than a reference number from a lower limit charge amount higher than a first reference charge amount to an upper limit charge amount lower than a second reference charge amount; based on a charge and discharge profile that discharges the battery cell with the current value a specific number of times from the upper limit charge amount to the lower limit charge amount, Further comprising an operation of obtaining at least one of the charging data, the discharging data, or any combination thereof. How to diagnose a battery.

14. In claim 8, The above deterioration indicators are, Including a loss of lithium inventory (LLI) including a first parameter related to lithium loss in the middle of life (MOL) compared to the beginning of life (BOL) of the battery cell, or A first LAM (loss of active material; LAM) comprising a second parameter related to the loss of active material of the negative plate in the MOL versus BOL of the battery cell, or A second LAM (loss of active material; LAM) is configured to include a third parameter related to the loss of active material of the positive electrode plate in the MOL versus BOL of the battery cell. How to diagnose a battery.

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